U.S. patent application number 17/490692 was filed with the patent office on 2022-03-31 for sstr-targeted conjugates and particles and formulations thereof.
The applicant listed for this patent is TARVEDA THERAPEUTICS, INC.. Invention is credited to Patrick Rosaire Bazinet, Mark T. Bilodeau, Sudhakar Kadiyala, Samantha Perino, Rajesh R. Shinde, Beata Sweryda-Krawiec, Kerry Whalen, Richard Wooster.
Application Number | 20220096646 17/490692 |
Document ID | / |
Family ID | 1000006010307 |
Filed Date | 2022-03-31 |
View All Diagrams
United States Patent
Application |
20220096646 |
Kind Code |
A1 |
Wooster; Richard ; et
al. |
March 31, 2022 |
SSTR-TARGETED CONJUGATES AND PARTICLES AND FORMULATIONS THEREOF
Abstract
Conjugates of an active agent such as DM1 attached to a
targeting moiety, such as a somatostatin receptor binding moiety,
via a linker, and particles comprising such conjugates have been
designed. Such conjugates and particles can provide improved
temporospatial delivery of the active agent, improved
biodistribution and penetration in tumor, and/or decreased
toxicity. Methods of making the conjugates, the particles, and the
formulations thereof are provided. Methods of administering the
formulations to a subject in need thereof are provided, for
example, to treat or prevent cancer.
Inventors: |
Wooster; Richard; (Natick,
MA) ; Whalen; Kerry; (Waltham, MA) ; Bazinet;
Patrick Rosaire; (Somerville, MA) ; Bilodeau; Mark
T.; (Waltham, MA) ; Kadiyala; Sudhakar;
(Newton, MA) ; Perino; Samantha; (Brighton,
MA) ; Sweryda-Krawiec; Beata; (Marlborough, MA)
; Shinde; Rajesh R.; (Lexington, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TARVEDA THERAPEUTICS, INC. |
Watertown |
MA |
US |
|
|
Family ID: |
1000006010307 |
Appl. No.: |
17/490692 |
Filed: |
September 30, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15770513 |
Apr 24, 2018 |
11160871 |
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PCT/US2016/059529 |
Oct 28, 2016 |
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17490692 |
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62304856 |
Mar 7, 2016 |
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62247336 |
Oct 28, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 47/6937 20170801;
A61K 47/64 20170801; A61K 31/506 20130101; A61K 45/06 20130101;
A61P 35/00 20180101; A61K 31/5365 20130101; A61K 31/655 20130101;
A61K 31/404 20130101; C07K 14/72 20130101; A61K 31/513 20130101;
A61K 31/436 20130101; A61K 31/7048 20130101; A61K 51/083
20130101 |
International
Class: |
A61K 47/64 20060101
A61K047/64; C07K 14/72 20060101 C07K014/72; A61K 47/69 20060101
A61K047/69; A61P 35/00 20060101 A61P035/00; A61K 31/404 20060101
A61K031/404; A61K 31/436 20060101 A61K031/436; A61K 31/506 20060101
A61K031/506; A61K 31/513 20060101 A61K031/513; A61K 31/5365
20060101 A61K031/5365; A61K 31/655 20060101 A61K031/655; A61K
31/7048 20060101 A61K031/7048; A61K 45/06 20060101 A61K045/06; A61K
51/08 20060101 A61K051/08 |
Claims
1. A method of reducing proliferation, increasing apoptosis or
increasing cell cycle arrest of cells, comprising administering a
conjugate to the cells, wherein the conjugate comprises an active
agent coupled to a somatostatin receptor (SSTR) targeting moiety by
a linker, wherein the active agent is mertansine (DM1).
2. The method of claim 1, wherein the cells express a somatostatin
receptor (SSTR).
3. The method of claim 2, wherein the cells express SSTR2.
4. The method of claim 3, wherein the cells are tumor cells.
5. The method of claim 4, wherein the cells are neuroendocrine
cancer cells.
6. The method of claim 5, wherein the cells are selected from small
cell lung cancer (SCLC), pheochromocytoma, neuroblastoma,
ganglioneuroma, paraganglioma, carcinoids, gastrinoma, glucagonoma,
vasoactive intestinal polypeptide-secreting tumor, pancreatic
polypeptide-secreting tumor, nonfunctioning gastroenteropancreatic
tumors, meduallary thyroid cancer, Merkel cell tumor of the skin,
pituitary adenoma, and pancreatic cancer cells.
7. The method of claim 3, wherein the cells are selected from brain
cancer, ovarian cancer, and colorectal cancer cells.
8. The method of claim 1, wherein the phospho-histone H3 levels in
the cells increase.
9. The method of claim 1, wherein the cleaved caspase-3 levels in
the cells increase.
10. The method of claim 1, wherein the conjugate is Conjugate
57.
11. A method of treating a tumor, reducing volume of a tumor or
delivering DM1 to a tumor in a subject, comprising: administering a
conjugate to the subject, wherein the conjugate comprises an active
agent coupled to a somatostatin receptor (SSTR) targeting moiety by
a linker, wherein the active agent is mertansine (DM1), and
administering an additional active agent.
12. The method of claim 11, wherein the tumor expresses a
somatostatin receptor (SSTR).
13. The method of claim 12, wherein the tumor expresses SSTR2.
14. The method of claim 12, wherein the SSTR internalizes into
cells after the conjugate is administered.
15. The method of claim 14, wherein the SSTR internalizes faster
than the SSTR on cells treated with octreotide.
16. The method of claim 11, wherein tumor is a neuroendocrine
cancer.
17. The method of claim 16, wherein the neuroendocrine cancer is
selected from small cell lung cancer (SCLC), pheochromocytoma,
neuroblastoma, ganglioneuroma, paraganglioma, carcinoids,
gastrinoma, glucagonoma, vasoactive intestinal
polypeptide-secreting tumor, pancreatic polypeptide-secreting
tumor, nonfunctioning gastroenteropancreatic tumors, meduallary
thyroid cancer, Merkel cell tumor of the skin, pituitary adenoma,
and pancreatic cancer.
18. The method of claim 17, wherein the tumor is selected from
neuroblastoma, breast cancer, brain cancer, ovarian cancer, and
colorectal cancer.
19. The method of claim 11, wherein the volume of the tumor is
reduced by about 60%.
20. The method of claim 11, wherein the subject has a positive scan
result detected with SSTR scintigraphy or positron emission
tomography (PET).
21. The method of claim 20, wherein Indium-111-labelled
pentetreotide is used in the SSTR scintigraphy or 68Ga-DOTA-TATE,
68Ga-DOTA-TOC, and 68Ga-DOTA-NOC in PET.
22. The method of claim 21, wherein the body weight of the subject
decreases less than about 30%, about 20%, about 15%, about 10% or
about 5% after administering the conjugate.
23. The method of claim 11, wherein the complete blood count (CBC)
or white blood cell (WBC) count of the subject decreases less than
about 30%, about 20%, about 15%, about 10%, or about 5% after
administering the conjugate.
24. The method of claim 11, wherein the AST or ALT level of the
subject increases less than about 30%, about 20%, about 15%, about
10%, or about 5% after administering the conjugate.
25. The method of claim 11, wherein the conjugate reaches at least
about 25, about 30, about 35, about 40, about 45, about 50, about
100, about 150, about 200, about 250, about 300, about 400, about
500, about 600, about 700, about 800, about 900, about 1000, about
1100, about 1200, about 1300, about 1400 or about 1500 .mu.m into
the tumor from the vascular surface of the tumor.
26. The method of claim 11, wherein the conjugate penetrates to the
core of the tumor.
27. The method of claim 11, wherein the conjugate penetrates to the
middle of the tumor.
28. The method of claim 11, wherein the conjugate is selected from
any conjugate in Tables 1, 2, 3, and 4.
29. The method of claim 11, wherein the conjugate is Conjugate
57.
30. The method of claim 11, wherein the additional active agent
does not bind to SSTR.
31. The method of claim 11, wherein the additional active agent is
a cancer symptom relief drug.
32. The method of claim 11, wherein the cancer symptom relief drug
treats carcinoid syndrome.
33. The method of claim 31, wherein the cancer symptom relief drug
is telotristat or telotristat etiprate.
34. The method of claim 11, wherein the additional active agent
treats cancer.
35. The method of claim 34, wherein the additional active agent
treats a neuroendocrine tumor, kidney cancer, breast cancer, or
brain cancer.
36. The method of claim 34, wherein the additional active agent is
a Lu-177-labeled somatostatin analogue peptide (lutathera),
everolimus (Afinitor.RTM.), capecitabine (Xeloda.RTM.), etoposide
(Etopophos.RTM.), sunitinib, dacarbazine, or fluorouracil.
Description
REFERENCED TO RELATED APPLICATIONS
[0001] The present application is a continuation application of
U.S. Nonprovisional patent application Ser. No. 15/770,513 filed
Apr. 24, 2018, which is a 35 U.S.C. .sctn. 371 U.S. National Stage
Entry of International Application No. PCT/US2016/059529 filed Oct.
28, 2016, which claims priority to U.S. Provisional Patent
Application No. 62/247,336, filed Oct. 28, 2015, entitled
SSTR-TARGETED CONJUGATES AND PARTICLES AND FORMULATIONS THEREOF,
U.S. Provisional Patent Application No. 62/304,856, filed Mar. 7,
2016, entitled SSTR-TARGETED CONJUGATES AND PARTICLES AND
FORMULATIONS THEREOF, the contents of each of which are herein
incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The invention generally relates to the field of targeting
ligands, conjugates thereof, and particles for drug delivery. More
particularly, the invention relates to the use of molecules
targeting somatostatin receptors, e.g., for treating cancer.
BACKGROUND OF THE INVENTION
[0003] Developments in nanomedicine are generally directed towards
improving the pharmaceutical properties of the drugs and, in some
cases, enhancing the targeted delivery in a more cell-specific
manner. Several cell-specific drugs have been described, and
include monoclonal antibodies, aptamers, peptides, and small
molecules. Despite some of the potential advantages of such drugs,
a number of problems have limited their clinical application,
including size, stability, manufacturing cost, immunogenicity, poor
pharmacokinetics and other factors.
[0004] Nanoparticulate drug delivery systems are attractive for
systemic drug delivery because they may be able to prolong the
half-life of a drug in circulation, reduce non-specific uptake of a
drug, and improve accumulation of a drug at tumors, e.g., through
an enhanced permeation and retention (EPR) effect. There are
limited examples of therapeutics formulated for delivery as
nanoparticles, which include DOXIL.RTM. (liposomal encapsulated
doxyrubicin) and ABRAXANE.RTM. (albumin bound paclitaxel
nanoparticles).
[0005] The development of nanotechnologies for effective delivery
of drugs or drug candidates to specific diseased cells and tissues,
e.g., to cancer cells, in specific organs or tissues, in a
temporospatially regulated manner potentially can overcome or
ameliorate therapeutic challenges, such as systemic toxicity.
However, while targeting of the delivery system may preferentially
deliver drug to a site where therapy is needed, the drug released
from the nanoparticle may not for example, remain in the region of
the targeted cells in efficacious amounts or may not remain in the
circulation in a relatively non-toxic state for a sufficient amount
of time to decrease the frequency of treatment or permit a lower
amount of drug to be administered while still achieving a
therapeutic effect. Antibody drug conjugates comprise an antibody
and a cytotoxic payload have been designed. However, the size of
antibodies limits solid tumor penetration compared to smaller
targeting ligands (see Xiang et al., Theranostics, vol.
5(10):1083-1097 (2015), the contents of which are incorporated
herein by reference in their entirety). Smaller targeting ligands
also penetrate solid tumors faster, which is important for payloads
that require a high tumor C.sub.max. Accordingly, there is a need
in the art for improved drug targeting and delivery and to design
drugs with deeper solid tumor penetration.
SUMMARY OF THE INVENTION
[0006] Applicants have created molecules that are conjugates of a
somatostatin receptor binding moiety and an active agent, e.g., a
cancer therapeutic agent such as a platinum-containing agent.
Furthermore, such conjugates can be encapsulated into particles.
The conjugates and particles are useful for delivering active
agents such as tumor cytotoxic agents to cells expressing
somatostatin receptors (SSTRs).
[0007] Applicants have developed novel conjugates and particles,
including polymeric nanoparticles, and pharmaceutical formulations
thereof. The conjugates of an active agent such as a therapeutic,
prophylactic, or diagnostic agent are attached via a linker to a
targeting moiety that can bind a somatostatin receptor. The
conjugates and particles can provide improved temporospatial
delivery of the active agent and/or improved biodistribution
compared to delivery of the active agent alone. In some cases, the
targeting moiety can also act as a therapeutic agent. In some
embodiments, the targeting agent does not substantially interfere
with efficacy of the therapeutic agent in vivo. Methods of making
conjugates, particles, and formulations comprising such particles
are described herein. Such particles are useful for treating or
preventing diseases that are susceptible to the active agent, for
example, treating or preventing cancer or infectious diseases.
[0008] The conjugates include a targeting ligand and an active
agent connected by a linker, wherein the conjugate in some
embodiments has the formula:
(X--Y--Z)
wherein X is a somatostatin receptor targeting moiety; Y is a
linker; and Z is an active agent. In one embodiment, the active
agent may be DM1.
[0009] In one aspect of the invention, a method of reducing
proliferation, increasing apoptosis, or increasing arrest of cells
is provided. The method comprises administering a conjugate to the
cells, wherein the conjugate comprises an active agent coupled to a
somatostatin receptor (SSTR) targeting moiety by a linker, wherein
the active agent is mertansine (DM1).
[0010] In another aspect of the invention, a method of treating a
tumor, reducing volume of a tumor or delivering DM1 to a tumor in a
subject is provided. The method comprises administering a conjugate
to the subject, wherein the conjugate comprises an active agent
coupled to a somatostatin receptor (SSTR) targeting moiety by a
linker, wherein the active agent is mertansine (DM1).
[0011] In yet another aspect of the invention, a method of treating
neuroendocrine cancers is provided, wherein the neuroendocrine
cancer is selected from small cell lung cancer (SCLC),
pheochromocytoma, neuroblastoma, ganglioneuroma, paraganglioma,
carcinoids, gastrinoma, glucagonoma, vasoactive intestinal
polypeptide-secreting tumor, pancreatic polypeptide-secreting
tumor, nonfunctioning gastroenteropancreatic tumors, meduallary
thyroid cancer, Merkel cell tumor of the skin, pituitary adenoma,
and pancreatic cancer. The method comprises administering a
conjugate to the cells, wherein the conjugate comprises an active
agent coupled to a somatostatin receptor (SSTR) targeting moiety by
a linker, wherein the active agent is mertansine (DM1).
[0012] In yet another aspect of the invention, a pharmaceutical
composition comprising a conjugate and an additional active agent
is provided, wherein the conjugate comprises an active agent
coupled to a somatostatin receptor (SSTR) targeting moiety by a
linker, and wherein the active agent is mertansine (DM1).
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is FIG. 6 of Dreher et al., JNCI, vol. 98(5):335
(2006).
[0014] FIG. 2A shows NCI-H524 cell proliferation with Conjugate 57
treatment and Conjugate 57+octreotide competition treatment. FIG.
2B shows NCI-H524 cell-cycle arrest with Conjugate 57 treatment and
Conjugate 57+octreotide competition treatment. FIG. 2C compares the
cell proliferation inhibition IC50 levels of H524 (Receptor +) and
H460 (Receptor -) cells with Conjugate 57 treatment alone
(competition -) and with Conjugate 57 treatment with competition
(competition +).
[0015] FIG. 3A shows increase in cell cycle arrest marker PH3 in
periphery, intermediate, and core of H69 SCLC tumors after
Conjugate 57 treatment. FIG. 3B shows PH3 response from 24 hr to 72
hr. FIG. 3C shows PH3 response at 24 hr.
[0016] FIG. 4 shows histological section images from center of
NCI-H69 tumors that show PH3 and CC3 levels after Conjugate 57
treatment.
[0017] FIG. 5 shows cleaved caspase-3 levels in NCI-H69 tumors
after a single dose of 2 mg/kg of Conjugate 57.
[0018] FIG. 6 shows mean tumor volumes of NCI-H69 tumors after 2
doses of Conjugate 57.
[0019] FIG. 7 shows mean tumor volumes of NCI-H524 tumors after 2
doses of Conjugate 57.
[0020] FIG. 8 shows mean body weight of animals treated with
Conjugate 57.
[0021] FIG. 9 shows NCI-H69 tumor volumes after treatment with
Conjugate 57 or treatment with the standard of care
combination.
[0022] FIG. 10 shows NCI-H82 tumor volumes after treatments with
Conjugate 57 or DM1.
[0023] FIG. 11A shows tumor volume measures of a dose response
study with different doses of Conjugate 57 in NCI-H524 SCLC model.
FIG. 11B shows body weight changes of the animals treated with
different doses of Conjugate 57.
[0024] FIG. 12 shows NCI-H69 tumor volume changes with Conjugate 57
or Conjugate 120 treatment.
[0025] FIG. 13 shows mean concentrations of Conjugate 57 over time
in mouse, rat or dog plasma.
[0026] FIG. 14 shows log clearance of Conjugate 57 over log body
weight in mouse, rat and dog.
[0027] FIG. 15 shows white blood cell (WBC) counts in SD rats
treated with DM1 or Conjugate 57.
[0028] FIGS. 16A and 16B show levels of liver toxicity markers: ALT
(FIG. 16A) and AST (FIG. 16B), in SD rats treated with DM1 or
Conjugate 57.
[0029] FIG. 17 shows IHC staining of various tumor cells as a
measurement of SSTR2 expression.
[0030] FIG. 18A shows Wester blot results of PH3 response in H69
tumors. FIG. 18B shows IHC results of PH3 response in H69
tumors.
[0031] FIG. 19 shows IHC results of CC3 response in H69 tumors.
[0032] FIG. 20 shows tumor volume changes with treatments with
conjugate alone and conjugate formulated in nanoparticles.
[0033] FIG. 21 shows PH3 and CC3 fold change compared to vehicle in
H69 tumors with Conjugate 57 treatment.
[0034] FIGS. 22A and 22B show PH3 (FIG. 22A) and CC3 (FIG. 22B)
staining images in the periphery, intermediate and core of H69
tumor 24 hr and 72 hr after Conjugate 57 treatment.
[0035] FIG. 23 shows efficacy of Conjugate 57 in treating HCC-33
tumor.
[0036] FIG. 24A shows remaining % of Conjugate 57 in plasma when it
is administered alone or in different nanoparticle formulations.
FIG. 24B shows Conjugate 57 concentration change in rat plasma when
it is administered alone or in different nanoparticle
formulations.
[0037] FIG. 25A showed SSTR2 receptor internalization intensity.
FIG. 25B showed SSTR2 internationalization in H524-MD tumor
xenografts at different times. FIG. 25C showed levels of SSTR2
internalization distribution. FIG. 25D showed SSTR2 internal
cellular distribution in H524 tumor xenografts at different
times.
[0038] FIG. 26A showed competitive assay results in IMR-32 cells
treated with Conjugate 57 with and without Octreotide. FIG. 26B
showed tumor volume change in mice bearing passage 3 IMR-32 tumors
treated with Conjugate 57.
[0039] FIG. 27 showed TGI % of HCC-33 xenograft treated with
Conjugate 57.
[0040] FIG. 28 compared tumor penetrations of a conjugate and an
antibody in small cell lung cancer.
DETAILED DESCRIPTION OF THE INVENTION
[0041] At least five somatostatin receptors subtypes have been
characterized, and tumors can express various receptor subtypes.
(e.g., see Shaer et al., Int. 3. Cancer 70:530-537, 1997).
Naturally occurring somatostatin and its analogs exhibit
differential binding to receptor subtypes. Applicants have
exploited this feature to create novel particles to improve
targeting of a conjugate comprising an active agent to a disease
tissue target. Such targeting can, for example, improve the amount
of active agent at a site and decrease active agent toxicity to the
subject. As used herein, "toxicity" refers to the capacity of a
substance or composition to be harmful or poisonous to a cell,
tissue organism or cellular environment. Low toxicity refers to a
reduced capacity of a substance or composition to be harmful or
poisonous to a cell, tissue organism or cellular environment. Such
reduced or low toxicity may be relative to a standard measure,
relative to a treatment or relative to the absence of a
treatment.
[0042] Toxicity may further be measured relative to a subject's
weight loss where weight loss over 15%, over 20% or over 30% of the
body weight is indicative of toxicity. Other metrics of toxicity
may also be measured such as patient presentation metrics including
lethargy and general malaiase. Neutropenia or thrombopenia may also
be metrics of toxicity.
[0043] Pharmacologic indicators of toxicity include elevated
AST/ALT levels, neurotoxicity, kidney damage, GI damage and the
like.
[0044] The conjugates are released after administration of the
particles. The targeted drug conjugates utilize active molecular
targeting in combination with enhanced permeability and retention
effect (EPR) and improved overall biodistribution of the particles
to provide greater efficacy and tolerability as compared to
administration of targeted particles or encapsulated untargeted
drug.
[0045] In addition, the toxicity of a conjugate containing a
somatostatin targeting moiety linked to an active agent for cells
that do not express SSTRs is predicted to be decreased compared to
the toxicity of the active agent alone. Without committing to any
particular theory, applicants believe that this feature is because
the ability of the conjugated active agent to enter a cell is
decreased compared the ability to enter a cell of the active agent
alone. Accordingly, the conjugates comprising an active agent and
particles containing the conjugates as described herein generally
have decreased toxicity for non-SSTR expressing cells and at least
the same or increased toxicity for SSTR expressing cells compared
to the active agent alone.
[0046] It is an object of the invention to provide improved
compounds, compositions, and formulations for temporospatial drug
delivery.
[0047] It is further an object of the invention to provide methods
of making improved compounds, compositions, and formulations for
temporospatial drug delivery.
[0048] It is also an object of the invention to provide methods of
administering the improved compounds, compositions, and
formulations to individuals in need thereof.
I. Conjugates
[0049] Conjugates include an active agent or prodrug thereof
attached to a targeting moiety, e.g., a molecule that can bind to
an SSTR, by a linker. The conjugates can be a conjugate between a
single active agent and a single targeting moiety, e.g., a
conjugate having the structure X--Y--Z where X is the targeting
moiety, Y is the linker, and Z is the active agent.
[0050] In some embodiments the conjugate contains more than one
targeting moiety, more than one linker, more than one active agent,
or any combination thereof. The conjugate can have any number of
targeting moieties, linkers, and active agents. The conjugate can
have the structure X--Y--Z--Y--X, (X--Y).sub.n--Z, X--(Y--Z).sub.n,
X--Y--Z.sub.n, (X--Y--Z).sub.n, (X--Y--Z--Y).sub.n--Z where X is a
targeting moiety, Y is a linker, Z is an active agent, and n is an
integer between 1 and 50, between 2 and 20, for example, between 1
and 5. Each occurrence of X, Y, and Z can be the same or different,
e.g., the conjugate can contain more than one type of targeting
moiety, more than one type of linker, and/or more than one type of
active agent.
[0051] The conjugate can contain more than one targeting moiety
attached to a single active agent. For example, the conjugate can
include an active agent with multiple targeting moieties each
attached via a different linker. The conjugate can have the
structure X--Y--Z--Y--X where each X is a targeting moiety that may
be the same or different, each Y is a linker that may be the same
or different, and Z is the active agent.
[0052] The conjugate can contain more than one active agent
attached to a single targeting moiety. For example the conjugate
can include a targeting moiety with multiple active agents each
attached via a different linker. The conjugate can have the
structure Z--Y--X--Y--Z where X is the targeting moiety, each Y is
a linker that may be the same or different, and each Z is an active
agent that may be the same or different.
A. Active Agents
[0053] A conjugate as described herein contains at least one active
agent (a first active agent). The conjugate can contain more than
one active agent, that can be the same or different from the first
active agent. The active agent can be a therapeutic, prophylactic,
diagnostic, or nutritional agent. A variety of active agents are
known in the art and may be used in the conjugates described
herein. The active agent can be a protein or peptide, small
molecule, nucleic acid or nucleic acid molecule, lipid, sugar,
glycolipid, glycoprotein, lipoprotein, or combination thereof. In
some embodiments, the active agent is an antigen, an adjuvant,
radioactive, an imaging agent (e.g., a fluorescent moiety) or a
polynucleotide. In some embodiments the active agent is an
organometallic compound.
Anti-Cancer Agents
[0054] The active agent can be a cancer therapeutic. Cancer
therapeutics include, for example, death receptor agonists such as
the TNF-related apoptosis-inducing ligand (TRAIL) or Fas ligand or
any ligand or antibody that binds or activates a death receptor or
otherwise induces apoptosis. Suitable death receptors include, but
are not limited to, TNFR1, Fas, DR3, DR4, DR5, DR6, LT.beta.R and
combinations thereof.
[0055] Cancer therapeutics such as chemotherapeutic agents,
cytokines, chemokines, and radiation therapy agents can be used as
active agents. Chemotherapeutic agents include, for example,
alkylating agents, antimetabolites, anthracyclines, plant
alkaloids, topoisomerase inhibitors, and other antitumor agents.
Such agents typically affect cell division or DNA synthesis and
function. Additional examples of therapeutics that can be used as
active agents include monoclonal antibodies and the tyrosine kinase
inhibitors e.g. imatinib mesylate, which directly targets a
molecular abnormality in certain types of cancer (e.g., chronic
myelogenous leukemia, gastrointestinal stromal tumors).
[0056] Chemotherapeutic agents include, but are not limited to
cisplatin, carboplatin, oxaliplatin, mechlorethamine,
cyclophosphamide, chlorambucil, vincristine, vinblastine,
vinorelbine, vindesine, taxol and derivatives thereof, irinotecan,
topotecan, amsacrine, etoposide, etoposide phosphate, teniposide,
epipodophyllotoxins, trastuzumab, cetuximab, and rituximab,
bevacizumab, and combinations thereof. Any of these may be used as
an active agent in a conjugate.
[0057] In some embodiments, the active agent can be 20-epi-1,25
dihydroxyvitamin D3, 4-ipomeanol, 5-ethynyluracil, 9-dihydrotaxol,
abiraterone, acivicin, aclarubicin, acodazole hydrochloride,
acronine, acylfulvene, adecypenol, adozelesin, aldesleukin, all-tk
antagonists, altretamine, ambamustine, ambomycin, ametantrone
acetate, amidox, amifostine, aminoglutethimide, aminolevulinic
acid, amrubicin, amsacrine, anagrelide, anastrozole,
andrographolide, angiogenesis inhibitors, antagonist D, antagonist
G, antarelix, anthramycin, anti-dorsalizing morphogenetic
protein-1, antiestrogen, antineoplaston, antisense
oligonucleotides, aphidicolin glycinate, apoptosis gene modulators,
apoptosis regulators, apurinic acid, ARA-CDP-DL-PTBA, arginine
deaminase, asparaginase, asperlin, asulacrine, atamestane,
atrimustine, axinastatin 1, axinastatin 2, axinastatin 3,
azacitidine, azasetron, azatoxin, azatyrosine, azetepa, azotomycin,
baccatin III derivatives, balanol, batimastat, benzochlorins,
benzodepa, benzoylstaurosporine, beta lactam derivatives,
beta-alethine, betaclamycin B, betulinic acid, BFGF inhibitor,
bicalutamide, bisantrene, bisantrene hydrochloride,
bisaziridinylspermine, bisnafide, bisnafide dimesylate, bistratene
A, bizelesin, bleomycin, bleomycin sulfate, BRC/ABL antagonists,
breflate, brequinar sodium, bropirimine, budotitane, busulfan,
buthionine sulfoximine, cabazitaxel, cactinomycin, calcipotriol,
calphostin C, calusterone, camptothecin, camptothecin derivatives,
canarypox IL-2, capecitabine, caracemide, carbetimer, carboplatin,
carboxamide-amino-triazole, carboxyamidotriazole, carest M3,
carmustine, earn 700, cartilage derived inhibitor, carubicin
hydrochloride, carzelesin, casein kinase inhibitors, castano
spermine, cecropin B, cedefingol, cetrorelix, chlorambucil,
chlorins, chloroquinoxaline sulfonamide, cicaprost, cirolemycin,
cisplatin, cis-porphyrin, cladribine, clomifene analogs,
clotrimazole, collismycin A, collismycin B, combretastatin A4,
combretastatin analog, conagenin, crambescidin 816, crisnatol,
crisnatol mesylate, cryptophycin 8, cryptophycin A derivatives,
curacin A, cyclopentanthraquinones, cyclophosphamide, cycloplatam,
cypemycin, cytarabine, cytarabine ocfosfate, cytolytic factor,
cytostatin, dacarbazine, dacliximab, dactinomycin, daunorubicin
hydrochloride, decitabine, dehydrodidemnin B, deslorelin,
dexifosfamide, dexormaplatin, dexrazoxane, dexverapamil,
dezaguanine, dezaguanine mesylate, diaziquone, didemnin B, didox,
diethylnorspermine, dihydro-5-azacytidine, dioxamycin, diphenyl
spiromustine, docetaxel, docosanol, dolasetron, doxifluridine,
doxorubicin, doxorubicin hydrochloride, droloxifene, droloxifene
citrate, dromostanolone propionate, dronabinol, duazomycin,
duocarmycin SA, ebselen, ecomustine, edatrexate, edelfosine,
edrecolomab, eflornithine, eflornithine hydrochloride, elemene,
elsamitrucin, emitefur, enloplatin, enpromate, epipropidine,
epirubicin, epirubicin hydrochloride, epristeride, erbulozole,
erythrocyte gene therapy vector system, esorubicin hydrochloride,
estramustine, estramustine analog, estramustine phosphate sodium,
estrogen agonists, estrogen antagonists, etanidazole, etoposide,
etoposide phosphate, etoprine, exemestane, fadrozole, fadrozole
hydrochloride, fazarabine, fenretinide, filgrastim, finasteride,
flavopiridol, flezelastine, floxuridine, fluasterone, fludarabine,
fludarabine phosphate, fluorodaunorunicin hydrochloride,
fluorouracil, flurocitabine, forfenimex, formestane, fosquidone,
fostriecin, fostriecin sodium, fotemustine, gadolinium texaphyrin,
gallium nitrate, galocitabine, ganirelix, gelatinase inhibitors,
gemcitabine, gemcitabine hydrochloride, glutathione inhibitors,
hepsulfam, heregulin, hexamethylene bisacetamide, hydroxyurea,
hypericin, ibandronic acid, idarubicin, idarubicin hydrochloride,
idoxifene, idramantone, ifosfamide, ilmofosine, ilomastat,
imidazoacridones, imiquimod, immunostimulant peptides, insulin-like
growth factor-1 receptor inhibitor, interferon agonists, interferon
alpha-2A, interferon alpha-2B, interferon alpha-N1, interferon
alpha-N3, interferon beta-IA, interferon gamma-IB, interferons,
interleukins, iobenguane, iododoxorubicin, iproplatin, irinotecan,
irinotecan hydrochloride, iroplact, irsogladine, isobengazole,
isohomohalicondrin B, itasetron, jasplakinolide, kahalalide F,
lamellarin-N triacetate, lanreotide, larotaxel, lanreotide acetate,
leinamycin, lenograstim, lentinan sulfate, leptolstatin, letrozole,
leukemia inhibiting factor, leukocyte alpha interferon, leuprolide
acetate, leuprolide/estrogen/progesterone, leuprorelin, levamisole,
liarozole, liarozole hydrochloride, linear polyamine analog,
lipophilic disaccharide peptide, lipophilic platinum compounds,
lissoclinamide 7, lobaplatin, lombricine, lometrexol, lometrexol
sodium, lomustine, lonidamine, losoxantrone, losoxantrone
hydrochloride, lovastatin, loxoribine, lurtotecan, lutetium
texaphyrin, lysofylline, lytic peptides, maitansine, mannostatin A,
marimastat, masoprocol, maspin, matrilysin inhibitors, matrix
metalloproteinase inhibitors, maytansine, maytansinoid, mertansine
(DM1), mechlorethamine hydrochloride, megestrol acetate,
melengestrol acetate, melphalan, menogaril, merbarone,
mercaptopurine, meterelin, methioninase, methotrexate, methotrexate
sodium, metoclopramide, metoprine, meturedepa, microalgal protein
kinase C inhibitors, MIF inhibitor, mifepristone, miltefosine,
mirimostim, mismatched double stranded RNA, mitindomide,
mitocarcin, mitocromin, mitogillin, mitoguazone, mitolactol,
mitomalcin, mitomycin, mitomycin analogs, mitonafide, mitosper,
mitotane, mitotoxin fibroblast growth factor-saporin, mitoxantrone,
mitoxantrone hydrochloride, mofarotene, molgramostim, monoclonal
antibody, human chorionic gonadotrophin, monophosphoryl lipid
a/myobacterium cell wall SK, mopidamol, multiple drug resistance
gene inhibitor, multiple tumor suppressor 1-based therapy, mustard
anticancer agent, mycaperoxide B, mycobacterial cell wall extract,
mycophenolic acid, myriaporone, n-acetyldinaline, nafarelin,
nagrestip, naloxone/pentazocine, napavin, naphterpin, nartograstim,
nedaplatin, nemorubicin, neridronic acid, neutral endopeptidase,
nilutamide, nisamycin, nitric oxide modulators, nitroxide
antioxidant, nitrullyn, nocodazole, nogalamycin, n-substituted
benzamides, 06-benzylguanine, octreotide, okicenone,
oligonucleotides, onapristone, ondansetron, oracin, oral cytokine
inducer, ormaplatin, osaterone, oxaliplatin, oxaunomycin, oxisuran,
paclitaxel, paclitaxel analogs, paclitaxel derivatives, palauamine,
palmitoylrhizoxin, pamidronic acid, panaxytriol, panomifene,
parabactin, pazelliptine, pegaspargase, peldesine, peliomycin,
pentamustine, pentosan polysulfate sodium, pentostatin, pentrozole,
peplomycin sulfate, perflubron, perfosfamide, perillyl alcohol,
phenazinomycin, phenylacetate, phosphatase inhibitors, picibanil,
pilocarpine hydrochloride, pipobroman, piposulfan, pirarubicin,
piritrexim, piroxantrone hydrochloride, placetin A, placetin B,
plasminogen activator inhibitor, platinum(IV) complexes, platinum
compounds, platinum-triamine complex, plicamycin, plomestane,
porfimer sodium, porfiromycin, prednimustine, procarbazine
hydrochloride, propyl bis-acridone, prostaglandin J2, prostatic
carcinoma antiandrogen, proteasome inhibitors, protein A-based
immune modulator, protein kinase C inhibitor, protein tyrosine
phosphatase inhibitors, purine nucleoside phosphorylase inhibitors,
puromycin, puromycin hydrochloride, purpurins, pyrazofurin,
pyrazoloacridine, pyridoxylated hemoglobin polyoxy ethylene
conjugate, RAF antagonists, raltitrexed, ramosetron, RAS farnesyl
protein transferase inhibitors, RAS inhibitors, RAS-GAP inhibitor,
retelliptine demethylated, rhenium RE 186 etidronate, rhizoxin,
riboprine, ribozymes, RII retinamide, RNAi, rogletimide,
rohitukine, romurtide, roquinimex, rubiginone Bl, ruboxyl,
safingol, safingol hydrochloride, saintopin, sarcnu, sarcophytol A,
sargramostim, SDI 1 mimetics, semustine, senescence derived
inhibitor 1, sense oligonucleotides, siRNA, signal transduction
inhibitors, signal transduction modulators, simtrazene, single
chain antigen binding protein, sizofiran, sobuzoxane, sodium
borocaptate, sodium phenylacetate, solverol, somatomedin binding
protein, sonermin, sparfosate sodium, sparfosic acid, sparsomycin,
spicamycin D, spirogermanium hydrochloride, spiromustine,
spiroplatin, splenopentin, spongistatin 1, squalamine, stem cell
inhibitor, stem-cell division inhibitors, stipiamide,
streptonigrin, streptozocin, stromelysin inhibitors, sulfinosine,
sulofenur, superactive vasoactive intestinal peptide antagonist,
suradista, suramin, swainsonine, synthetic glycosaminoglycans,
talisomycin, tallimustine, tamoxifen methiodide, tauromustine,
tazarotene, tecogalan sodium, tegafur, tellurapyrylium, telomerase
inhibitors, teloxantrone hydrochloride, temoporfin, temozolomide,
teniposide, teroxirone, testolactone, tetrachlorodecaoxide,
tetrazomine, thaliblastine, thalidomide, thiamiprine, thiocoraline,
thioguanine, thiotepa, thrombopoietin, thrombopoietin mimetic,
thymalfasin, thymopoietin receptor agonist, thymotrinan, thyroid
stimulating hormone, tiazofurin, tin ethyl etiopurpurin,
tirapazamine, titanocene dichloride, topotecan hydrochloride,
topsentin, toremifene, toremifene citrate, totipotent stem cell
factor, translation inhibitors, trestolone acetate, tretinoin,
triacetyluridine, triciribine, triciribine phosphate, trimetrexate,
trimetrexate glucuronate, triptorelin, tropisetron, tubulozole
hydrochloride, turosteride, tyrosine kinase inhibitors,
tyrphostins, UBC inhibitors, ubenimex, uracil mustard, uredepa,
urogenital sinus-derived growth inhibitory factor, urokinase
receptor antagonists, vapreotide, variolin B, velaresol, veramine,
verdins, verteporfin, vinblastine sulfate, vincristine sulfate,
vindesine, vindesine sulfate, vinepidine sulfate, vinglycinate
sulfate, vinleurosine sulfate, vinorelbine, vinorelbine tartrate,
vinrosidine sulfate, vinxaltine, vinzolidine sulfate, vitaxin,
vorozole, zanoterone, zeniplatin, zilascorb, zinostatin, zinostatin
stimalamer, or zorubicin hydrochloride.
[0058] In some embodiments, the active agent is a small molecule.
In some embodiments, the active agent is a small molecule
cytotoxin. In one embodiment, the active agent is cabazitaxel, or
an analog, derivative, prodrug, or pharmaceutically acceptable salt
thereof. In another embodiment, the active agent is mertansine
(DM1) or DM4, or an analog, derivative, prodrug, or
pharmaceutically acceptable salt thereof. DM1 or DM4 inhibits the
assembly of microtubules by binding to tubulin. Structure of DM1 is
shown below:
##STR00001##
[0059] The active agent can be an inorganic or organometallic
compound containing one or more metal centers. In some examples,
the compound contains one metal center. The active agent can be,
for example, a platinum compound, a ruthenium compound (e.g.,
trans-[RuCl.sub.2 (DMSO).sub.4], or
trans-MuCl.sub.4(imidazole).sub.2, etc.), cobalt compound, copper
compound, or iron compounds.
[0060] In certain embodiments, the active agent of the conjugate
comprises a predetermined molar weight percentage from about 1% to
about 10%, or about 10% to about 20%, or about 20% to about 30%, or
about 30% to about 40%, or about 40% to about 50%, or about 50% to
about 60%, or about 60% to about 70%, or about 70% to about 80%, or
about 80% to about 90%, or about 90% to about 99% such that the sum
of the molar weight percentages of the components of the conjugate
is 100%. The amount of active agent(s) of the conjugate may also be
expressed in terms of proportion to the targeting ligand(s). For
example, the present teachings provide a ratio of active agent to
ligand of about 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, 1:1,
1:2, 1:3, 1:4; 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.
B. Targeting Moieties
[0061] Targeting ligands (also referred to as targeting moieties)
as described herein include any molecule that can bind one or more
SSTRs, e.g., human SSTR1, SSTR2, SSTR3, SSTR4, or SSTRS. Such
targeting ligands can be peptides, antibody mimetics, nucleic acids
(e.g., aptamers), polypeptides (e.g., antibodies), glycoproteins,
small molecules, carbohydrates, or lipids. In some embodiments, the
targeting moiety is somatostatin or a somatostation analog.
[0062] The cytotoxic or therapeutic conjugates of the invention can
employ any somatostatin analog that binds somatostatin receptor. In
some embodiments, the somatostatin analog portion of the conjugate
contains between 8 and 18 amino acids, and includes the core
sequence: cyclo[Cys-Phe-D-Trp-Lys-Thr-Cys] (SEQ ID NO:1) or
cyclo[Cys-Tyr-D-Trp-Lys-Thr-Cys] (SEQ ID NO. 2). For example, the
C-terminus of the analog is Thr-NH2.
[0063] In one embodiment, the targeting moiety binds preferably to
SSTR2. Therefore, the conjugate comprising the targeting moiety
binds preferably to SSTR2. The binding of the conjugate to SSTR2 is
stronger than the binding of the conjugate to SSTR1, SSTR3, SSTR4
or SSTRS.
[0064] In some embodiments, the conjugates as described herein have
low membrane permeability. Membrane permeability may be low in both
the apical to basolateral direction and the basolateral to apical
direction. Not wiling to be bound by any theory, low membrane
permeability enhances selective uptake by SSTRs by decreasing
non-specific permeability. Low permeability leads to decreased
uptake in cells that do not express SSTR2, leading to lower
toxicity to non-SSTR2 expressing cells. Membrane permeability may
be determined by any method known in the art. For example, it may
be determined by measuring apparent permeability (Papp) in Caco-2
monolayers.
[0065] In some embodiments, the targeting moiety, X, may be
selected from somatostatin, octreotide, lanreotide, lutathera
(.sup.177Lu-DOTATATE), .sup.90Y-DOTATOC, Tyr.sup.3-octreotate
(TATE), vapreotide, cyclo(AA-Tyr-DTrp-Lys-Thr-Phe) where AA is
.alpha.-N-Me lysine or N-Me glutamic acid, pasireotide, lanreotide,
seglitide, or any other example of somatostatin receptor binding
ligands. In some embodiments, the targeting moiety is a
somatostatin receptor binding moiety that binds to somatostatin
receptors 2 and/or 5. In some embodiments, X binds to the linker
moiety Y at the C-terminal. In some embodiments, X binds to the
linker moiety Y at the N-terminal. In some embodiments, the
targeting moiety X comprises at least one D-Phe residue and the
phenyl ring of the D-Phe residue of the targeting moiety X has been
replaced by a linker-containing moiety.
[0066] Examples of somatostatin analogs that are peptides useful in
the present invention are described herein. Further examples useful
somatostatin analogs are disclosed in publications set forth below,
each of which is hereby incorporated by reference in its
entirety:
[0067] PCT Application No. WO 03/057214 (2003)
[0068] U.S. Application No. 20030191134 (2003)
[0069] U.S. Application No. 20030083241 (2003)
[0070] U.S. Pat. No. 6,316,414 (2001)
[0071] PCT Application No. WO 02/10215 (2002)
[0072] PCT Application No. WO 99/22735 (1999)
[0073] PCT Application No. WO 98/08100 (1998)
[0074] PCT Application No. WO 98/44921 (1998)
[0075] PCT Application No. WO 98/45285 (1998)
[0076] PCT Application No. WO 98/44922 (1998)
[0077] EP Application No. P5164 EU (Inventor: G. Keri);
[0078] Van Binst, G. et al., Peptide Research, 1992, 5:8;
[0079] Horvath, A. et al., Abstract, "Conformations of Somatostatin
Analogs Having Antitumor Activity", 22nd European peptide
Symposium, Sep. 13-19, 1992, Interlaken, Switzerland;
[0080] PCT Application No. WO 91/09056 (1991);
[0081] EP Application No. 0 363 589 A2 (1990);
[0082] U.S. Pat. No. 4,904,642 (1990);
[0083] U.S. Pat. No. 4,871,717 (1989);
[0084] U.S. Pat. No. 4,853,371 (1989);
[0085] U.S. Pat. No. 4,725,577 (1988);
[0086] U.S. Pat. No. 4,684,620 (1987);
[0087] U.S. Pat. No. 4,650,787 (1987);
[0088] U.S. Pat. No. 4,603,120 (1986);
[0089] U.S. Pat. No. 4,585,755 (1986);
[0090] EP Application No. 0 203 031 A2 (1986);
[0091] U.S. Pat. No. 4,522,813 (1985);
[0092] U.S. Pat. No. 4,486,415 (1984);
[0093] U.S. Pat. No. 4,485,101 (1984);
[0094] U.S. Pat. No. 4,435,385 (1984);
[0095] U.S. Pat. No. 4,395,403 (1983);
[0096] U.S. Pat. No. 4,369,179 (1983);
[0097] U.S. Pat. No. 4,360,516 (1982);
[0098] U.S. Pat. No. 4,358,439 (1982);
[0099] U.S. Pat. No. 4,328,214 (1982);
[0100] U.S. Pat. No. 4,316,890 (1982);
[0101] U.S. Pat. No. 4,310,518 (1982);
[0102] U.S. Pat. No. 4,291,022 (1981);
[0103] U.S. Pat. No. 4,238,481 (1980);
[0104] U.S. Pat. No. 4,235,886 (1980);
[0105] U.S. Pat. No. 4,224,199 (1980);
[0106] U.S. Pat. No. 4,211,693 (1980);
[0107] U.S. Pat. No. 4,190,648 (1980);
[0108] U.S. Pat. No. 4,146,612 (1979);
[0109] U.S. Pat. No. 4,133,782 (1979);
[0110] U.S. Pat. No. 5,506,339 (1996);
[0111] U.S. Pat. No. 4,261,885 (1981);
[0112] U.S. Pat. No. 4,728,638 (1988);
[0113] U.S. Pat. No. 4,282,143 (1981);
[0114] U.S. Pat. No. 4,215,039 (1980);
[0115] U.S. Pat. No. 4,209,426 (1980);
[0116] U.S. Pat. No. 4,190,575 (1980);
[0117] EP Patent No. 0 389 180 (1990);
[0118] EP Application No. 0 505 680 (1982);
[0119] EP Application No. 0 083 305 (1982);
[0120] EP Application No. 0 030 920 (1980);
[0121] PCT Application No. WO 88/05052 (1988);
[0122] PCT Application No. WO 90/12811 (1990);
[0123] PCT Application No. WO 97/01579 (1997);
[0124] PCT Application No. WO 91/18016 (1991);
[0125] U.K. Application No. GB 2,095,261 (1981);
[0126] French Application No. FR 2,522,655 (1983); and
[0127] PCT Application No. WO 04/093807 (2004).
[0128] U.S. Pat. No. 5,620,955 (1997)
[0129] U.S. Pat. No. 5,723,578 (1998)
[0130] U.S. Pat. No. 5,843,903 (1998)
[0131] U.S. Pat. No. 5,877,277 (1999)
[0132] U.S. Pat. No. 6,156,725 (2000)
[0133] U.S. Pat. No. 6,307,017 (2001)
[0134] PCT Application No. WO 90/03980 (1990)
[0135] PCT Application No. WO 91/06563 (1991)
[0136] PCT Application No. WO 91/17181 (1991)
[0137] PCT Application No. WO 94/02018 (1994)
[0138] PCT Application No. WO 94/21674 (1994)
[0139] PCT Application No. WO 04/093807 (2004);
[0140] Methods for synthesizing somatostatin peptides and analogs
are well documented and are within the ability of a person of
ordinary skill in the art as exemplified in the references listed
supra. Further synthetic procedures are provided in the following
examples. The following examples also illustrate methods for
synthesizing the targeted cytotoxic compounds of the present
invention. Specific targeting of therapeutic or cytotoxic agents
allows selective destruction of a tumor expressing a receptor
specific for a biologically active peptide. For example, a tumor
expressing a somatostatin receptor includes a neoplasm of the lung,
breast, prostate, colon, brain, gastrointestinal tract,
neuroendocrine axis, liver, or kidney (see Schaer et al., Int. J.
Cancer, 70:530-537, 1997; Chave et al., Br. J. Cancer
82(1):124-130, 2000; Evans et al., Br. J. Cancer 75(6):798-803,
1997).
[0141] In some embodiments, the targeting moiety has therapeutic
features, e.g., the targeting moiety is cytotoxic or
anti-angiogenic. In some embodiments, a targeting moiety has some
increased affinity for tumor vasculature, or angiogenic blood
vessels, e.g., those that over-express somatostatin receptors (see
Denzler and Reubi, Cancer 85:188-198, 1999; Gulec et al., J. Surg.
Res. 97(2):131-137, 2001; Woltering et al., J. Surg. Res. 50:245,
1991).
[0142] In some embodiments, the targeting moiety, e.g.,
somatostatin analog, used in the invention is hydrophilic, and is
therefore water soluble. In some embodiments, such conjugates and
particles containing such conjugates are used in treatment
paradigms in which this feature is useful, e.g., compared to
conjugates comprising hydrophobic analogs. Hydrophilic analogs
described herein can be soluble in blood, cerebrospinal fluid, and
other bodily fluids, as well as in urine, which may facilitate
excretion by the kidneys. This feature can be useful, e.g., in the
case of a composition that would otherwise exhibit undesirable
liver toxicity. The invention also discloses specific hydrophilic
elements (e.g., incorporation of a PEG linker, and other examples
in the art) for incorporation into peptide analogs, allowing
modulation of the analog's hydrophilicity to adjust for the
chemical and structural nature of the various conjugated cytotoxic
agents, e.g., conjugate 6 infra.
[0143] In some embodiments, the targeting moiety is an antibody
mimetic such as a monobody, e.g., an ADNECTIN.TM. (Bristol-Myers
Squibb, New York, N.Y.), an Affibody.RTM. (Affibody AB, Stockholm,
Sweden), Affilin, nanofitin (affitin, such as those described in WO
2012/085861, an Anticalin.TM., an avimers (avidity multimers), a
DARPin.TM., a Fynomer.TM., Centyrin.TM. and a Kunitz domain
peptide. In certain cases, such mimetics are artificial peptides or
proteins with a molar mass of about 3 to 20 kDa. Nucleic acids and
small molecules may be antibody mimetic.
[0144] In another example, a targeting moiety can be an aptamer,
which is generally an oligonucleotide (e.g., DNA, RNA, or an analog
or derivative thereof) that binds to a particular target, such as a
polypeptide. In some embodiments, the targeting moiety is a
polypeptide (e.g., an antibody that can specifically bind a tumor
marker). In certain embodiments, the targeting moiety is an
antibody or a fragment thereof. In certain embodiments, the
targeting moiety is an Fc fragment of an antibody.
[0145] In certain embodiments, the targeting moiety or moieties of
the conjugate are present at a predetermined molar weight
percentage from about 0.1% to about 10%, or about 1% to about 10%,
or about 10% to about 20%, or about 20% to about 30%, or about 30%
to about 40%, or about 40% to about 50%, or about 50% to about 60%,
or about 60% to about 70%, or about 70% to about 80%, or about 80%
to about 90%, or about 90% to about 99% such that the sum of the
molar weight percentages of the components of the conjugate is
100%. The amount of targeting moieties of the conjugate may also be
expressed in terms of proportion to the active agent(s), for
example, in a ratio of ligand to active agent of about 10:1, 9:1,
8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4; 1:5, 1:6,
1:7, 1:8, 1:9, or 1:10.
C. Linkers
[0146] The conjugates contain one or more linkers attaching the
active agents and targeting moieties. The linker, Y, is bound to
one or more active agents and one or more targeting ligands to form
a conjugate. The linker Y is attached to the targeting moiety X and
the active agent Z by functional groups independently selected from
an ester bond, disulfide, amide, acylhydrazone, ether, carbamate,
carbonate, and urea. Alternatively the linker can be attached to
either the targeting ligand or the active drug by a non-cleavable
group such as provided by the conjugation between a thiol and a
maleimide, an azide and an alkyne. The linker is independently
selected from the group consisting alkyl, cycloalkyl, heterocyclyl,
aryl, and heteroaryl, wherein each of the alkyl, alkenyl,
cycloalkyl, heterocyclyl, aryl, and heteroaryl groups optionally is
substituted with one or more groups, each independently selected
from halogen, cyano, nitro, hydroxyl, carboxyl, carbamoyl, ether,
alkoxy, aryloxy, amino, amide, carbamate, alkyl, alkenyl, alkynyl,
aryl, arylalkyl, cycloalkyl, heteroaryl, heterocyclyl, wherein each
of the carboxyl, carbamoyl, ether, alkoxy, aryloxy, amino, amide,
carbamate, alkyl, alkenyl, alkynyl, aryl, arylalkyl, cycloalkyl,
heteroaryl, or heterocyclyl is optionally substituted with one or
more groups, each independently selected from halogen, cyano,
nitro, hydroxyl, carboxyl, carbamoyl, ether, alkoxy, aryloxy,
amino, amide, carbamate, alkyl, alkenyl, alkynyl, aryl, arylalkyl,
cycloalkyl, heteroaryl, heterocyclyl.
[0147] In some embodiments, the linker comprises a cleavable
functionality that is cleavable. The cleavable functionality may be
hydrolyzed in vivo or may be designed to be hydrolyzed
enzymatically, for example by Cathepsin B. A "cleavable" linker, as
used herein, refers to any linker which can be cleaved physically
or chemically. Examples for physical cleavage may be cleavage by
light, radioactive emission or heat, while examples for chemical
cleavage include cleavage by re-dox-reactions, hydrolysis,
pH-dependent cleavage or cleavage by enzymes.
[0148] In some embodiments the alkyl chain of the linker may
optionally be interrupted by one or more atoms or groups selected
from --O--, --C(.dbd.O)--, --NR, --O--C(.dbd.O)--NR--, --S--,
--S--S--. The linker may be selected from dicarboxylate derivatives
of succinic acid, glutaric acid or diglycolic acid. In some
embodiments, the linker Y may be X'--R.sup.1--Y'--R.sup.2--Z' and
the conjugate can be a compound according to Formula Ia:
##STR00002## [0149] wherein X is a targeting moiety defined above;
Z is an active agent; X', R.sup.1, Y', R.sup.2 and Z' are as
defined herein.
[0150] X' is either absent or independently selected from carbonyl,
amide, urea, amino, ester, aryl, arylcarbonyl, aryloxy, arylamino,
one or more natural or unnatural amino acids, thio or succinimido;
R.sup.1 and R.sup.2 are either absent or comprised of alkyl,
substituted alkyl, aryl, substituted aryl, polyethylene glycol
(2-30 units); Y' is absent, substituted or unsubstituted
1,2-diaminoethane, polyethylene glycol (2-30 units) or an amide; Z'
is either absent or independently selected from carbonyl, amide,
urea, amino, ester, aryl, arylcarbonyl, aryloxy, arylamino, thio or
succinimido. In some embodiments, the linker can allow one active
agent molecule to be linked to two or more ligands, or one ligand
to be linked to two or more active agent molecule.
[0151] In some embodiments, the linker Y may be A.sub.m and the
conjugate can be a compound according to Formula Ib:
##STR00003##
[0152] wherein A is defined herein, m=0-20.
[0153] A in Formula Ia is a spacer unit, either absent or
independently selected from the following substituents. For each
substituent, the dashed lines represent substitution sites with X,
Z or another independently selected unit of A wherein the X, Z, or
A can be attached on either side of the substituent:
##STR00004## ##STR00005##
wherein z=0-40, R is H or an optionally substituted alkyl group,
and R' is any side chain found in either natural or unnatural amino
acids.
[0154] In some embodiments, the conjugate may be a compound
according to Formula Ic:
##STR00006##
wherein A is defined above, m=0-40, n=0-40, x=1-5, y=1-5, and C is
a branching element defined herein.
[0155] C in Formula Ic is a branched unit containing three to six
functionalities for covalently attaching spacer units, ligands, or
active drugs, selected from amines, carboxylic acids, thiols, or
succinimides, including amino acids such as lysine,
2,3-diaminopropanoic acid, 2,4-diaminobutyric acid, glutamic acid,
aspartic acid, and cysteine.
[0156] Non-limiting examples of conjugates of the present invention
include the following compounds:
##STR00007## ##STR00008## ##STR00009## ##STR00010## ##STR00011##
##STR00012##
[0157] In some embodiments, the active agent Z is DM1 and the
somatostatin receptor binding agent X is selected from
somatostatin, cyclo(AA-Tyr-DTrp-Lys-Thr-Phe), vapreotide or TATE.
In some embodiments, DM1 is connected to the C-terminus of X with
the linker Y. In some embodiments, DM1 is connected to the
N-terminus of X with the linker Y. In some embodiments, DM1 is
connected to X with the linker Y, wherein the targeting moiety X
comprises at least one D-Phe residue and the phenyl ring of the
D-Phe residue has been replaced by a group containing linker Y.
[0158] Non-limiting examples of conjugates comprising DM1, referred
to as DM1 conjugates of the invention, include the following
compounds:
1) Cyclo(AA-Tyr-DTrp-Lys-Thr-Phe)-Based DM1 Conjugates
[0159] In some embodiments, cyclo(AA-Tyr-DTrp-Lys-Thr-Phe) is used
as a somatostatin receptor targeting moiety and the conjugates have
a general structure of:
##STR00013##
[0160] In some embodiments, the targeting moiety contains an amino
acid capable of making an amide bond. In some embodiments, the
linker is bound to the targeting moiety via an amide bond, i.e.,
--NH--CO--, or --CO--NH-- (the hydrogen on the nitrogen may be
substituted). In some embodiments, the linker is not bound to the
targeting moiety via an amide bond. In some embodiments, the linker
includes an amide bond, i.e., --NH--CO--, or --CO--NH-- (the
hydrogen on the nitrogen may be substituted).
[0161] Non-limiting examples of conjugates comprising
cyclo(AA-Tyr-DTrp-Lys-Thr-Phe) and DM1 are shown in Table 1:
TABLE-US-00001 TABLE 1 cyclo(AA-Tyr-DTrp-Lys-Thr-Phe)-based
Conjugates Linker* Full structure ##STR00014## ##STR00015## 10
##STR00016## ##STR00017## 12 ##STR00018## ##STR00019## 14
##STR00020## ##STR00021## 16 ##STR00022## ##STR00023## 18
##STR00024## ##STR00025## 20 ##STR00026## ##STR00027## 22
##STR00028## ##STR00029## 24 ##STR00030## ##STR00031## 26
##STR00032## ##STR00033## 28 ##STR00034## ##STR00035## 30
##STR00036## ##STR00037## 32 *In order to show linker structures,
the somatostatin receiptor targeting moiety is referred to as
ligand in the strctures.
2) C-Terminal DM1 Conjugates:
[0162] In some embodiments, the somatostatin receptor targeting
moiety is a peptide and the linker binds to the C-terminus of the
somatostatin receptor targeting moiety. In some embodiments, the
somatostatin receptor targeting moiety is TATE or a TATE
derivative, wherein the linker binds to the C-terminus of TATE or
the TATE derivative, referred to as C-terminal TATE-based DM1
conjugate. The C-terminal DM1 conjugates have a general structure
of:
##STR00038##
[0163] wherein R is selected from H, alkyl, aryl, carbonyl, amide,
alcohol, or amine, optionally substituted with one or more groups;
and
Ar.sub.1 and Ar.sub.2 are independently selected from heterocyclyl,
aryl, and heteroaryl groups optionally substituted with one or more
groups.
[0164] In some embodiments, the covalent bond connecting the linker
and the C-terminus of the somatostatin receptor targeting moiety is
an amide bond.
Non-limiting examples of DM1 conjugates wherein the linker binds to
the C-terminus of the somatostatin receptor targeting moiety,
wherein the somatostatin receptor targeting moiety is TATE, are
shown in Table 2:
TABLE-US-00002 TABLE 2 C-terminal TATE-based DM1 conjugates R Ar1
Ar2 Linker* Full Structure H ##STR00039## ##STR00040## ##STR00041##
##STR00042## H ##STR00043## ##STR00044## ##STR00045## ##STR00046##
H ##STR00047## ##STR00048## ##STR00049## ##STR00050## H
##STR00051## ##STR00052## ##STR00053## ##STR00054## H ##STR00055##
##STR00056## ##STR00057## ##STR00058## H ##STR00059## ##STR00060##
##STR00061## ##STR00062## H ##STR00063## ##STR00064## ##STR00065##
##STR00066## H ##STR00067## ##STR00068## ##STR00069## ##STR00070##
H ##STR00071## ##STR00072## ##STR00073## ##STR00074## H
##STR00075## ##STR00076## ##STR00077## ##STR00078## ##STR00079##
##STR00080## ##STR00081## ##STR00082## ##STR00083## H ##STR00084##
##STR00085## ##STR00086## ##STR00087## H ##STR00088## ##STR00089##
##STR00090## ##STR00091## H ##STR00092## ##STR00093## ##STR00094##
##STR00095## H ##STR00096## ##STR00097## ##STR00098## ##STR00099##
##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104##
##STR00105## *In order to show linker structures, the somatostatin
receiptor targeting moiety is referred to as ligand in the
strctures.
3) N-Terminal DM1 Conjugates
[0165] In some embodiments, the somatostatin receptor targeting
moiety is a peptide and the linker binds to the N-terminus of the
somatostatin receptor targeting moiety. In some embodiments, the
target moiety is selected from octreotide, vapreotide, and TATE. In
some embodiments, the covalent bond connecting the linker and the
N-terminal of the somatostatin receptor targeting moiety is an
amide bond, i.e., --NH--CO--. In some embodiments, the linker binds
to the N-terminus of the somatostatin receptor targeting moiety via
an amine bond, i.e., --NH--CH.sub.2-- (hydrogen on the carbon may
be substituted). In some embodiments, the linker binds to the
N-terminus of the somatostatin receptor targeting moiety via a urea
bond, i.e. --NH--CO--NH--. The N-terminal DM1 conjugate has a
general structure of:
##STR00106##
wherein R.sub.1 and R.sub.2 are independently selected from H, OH,
alkyl, aryl, carbonyl, ester, amide, ether, alcohol, or amine,
optionally substituted with one or more groups; and Ar.sub.1 is
selected from heterocyclyl, aryl, and heteroaryl groups optionally
substituted with one or more groups. In some embodiments, at least
one of R1 or R2 comprises DM1.
[0166] Non-limiting examples of DM1 conjugates wherein the linker
binds to the N-terminus of the somatostatin receptor targeting
moiety are shown in Table 3:
TABLE-US-00003 TABLE 3 N-terminal DM1 conjugates R.sub.1 R.sub.2
Ar.sub.1 Linker* Full structure ##STR00107## --OH ##STR00108##
##STR00109## ##STR00110## ##STR00111## --Me ##STR00112##
##STR00113## ##STR00114## ##STR00115## --OH ##STR00116##
##STR00117## ##STR00118## ##STR00119## --OH ##STR00120##
##STR00121## ##STR00122## ##STR00123## --OH ##STR00124##
##STR00125## ##STR00126## ##STR00127## --Me ##STR00128##
##STR00129## ##STR00130## ##STR00131## --OH ##STR00132##
##STR00133## ##STR00134## ##STR00135## --OH ##STR00136##
##STR00137## ##STR00138## ##STR00139## --OH ##STR00140##
##STR00141## ##STR00142## ##STR00143## --OH ##STR00144##
##STR00145## ##STR00146## ##STR00147## --OH ##STR00148##
##STR00149## ##STR00150## ##STR00151## --OH ##STR00152##
##STR00153## ##STR00154## ##STR00155## --OH ##STR00156##
##STR00157## ##STR00158## ##STR00159## --OH ##STR00160##
##STR00161## ##STR00162## ##STR00163## --OH ##STR00164##
##STR00165## ##STR00166## ##STR00167## --OH ##STR00168##
##STR00169## ##STR00170## ##STR00171## --OH ##STR00172##
##STR00173## ##STR00174## ##STR00175## --Me ##STR00176##
##STR00177## ##STR00178## ##STR00179## --OH ##STR00180##
##STR00181## ##STR00182## ##STR00183## --OH ##STR00184##
##STR00185## ##STR00186## ##STR00187## --OH ##STR00188##
##STR00189## ##STR00190## *In order to show linker structures, the
somatostatin receiptor targeting moiety is referred to as ligand in
the strctures.
4) D-Phe Replacement DM1 Conjugates
[0167] In some embodiments, the somatostatin receptor targeting
moiety is a targeting ligand such as octreotide or TATE, wherein
the phenyl ring of the D-Phe residue of the targeting ligand has
been replaced by a linker-containing moiety. The D-Phe replacement
DM1 conjugate has a general structure of:
##STR00191##
wherein R is selected from H, OH, alkyl, aryl, carbonyl, ester,
amide, ether, alcohol, or amine, optionally substituted with one or
more groups. In some embodiments, R comprises DM1.
[0168] Non-limiting examples of DM1 conjugates wherein the phenyl
ring of the D-Phe residue of the targeting ligand has been replaced
by a linker-containing moiety are shown in Table 4:
TABLE-US-00004 TABLE 4 D-Phe replacement DM1 conjugates R Linker*
Full structure H ##STR00192## ##STR00193## H ##STR00194##
##STR00195## H ##STR00196## ##STR00197## ##STR00198## ##STR00199##
##STR00200## H ##STR00201## ##STR00202## *In order to show linker
structures, the somatostatin receiptor targeting moiety is referred
to as ligand in the strctures.
II. Particles
[0169] Particles containing one or more conjugates can be polymeric
particles, lipid particles, solid lipid particles, inorganic
particles, or combinations thereof (e.g., lipid stabilized
polymeric particles). In some embodiments, the particles are
polymeric particles or contain a polymeric matrix. The particles
can contain any of the polymers described herein or derivatives or
copolymers thereof. The particles generally contain one or more
biocompatible polymers. The polymers can be biodegradable polymers.
The polymers can be hydrophobic polymers, hydrophilic polymers, or
amphiphilic polymers. In some embodiments, the particles contain
one or more polymers having an additional targeting moiety attached
thereto.
[0170] The size of the particles can be adjusted for the intended
application. The particles can be nanoparticles or microparticles.
The particle can have a diameter of about 10 nm to about 10
microns, about 10 nm to about 1 micron, about 10 nm to about 500
nm, about 20 nm to about 500 nm, or about 25 nm to about 250 nm. In
some embodiments the particle is a nanoparticle having a diameter
from about 25 nm to about 250 nm. It is understood by those in the
art that a plurality of particles will have a range of sizes and
the diameter is understood to be the median diameter of the
particle size distribution.
[0171] In various embodiments, a particle may be a nanoparticle,
i.e., the particle has a characteristic dimension of less than
about 1 micrometer, where the characteristic dimension of a
particle is the diameter of a perfect sphere having the same volume
as the particle. The plurality of particles can be characterized by
an average diameter (e.g., the average diameter for the plurality
of particles). In some embodiments, the diameter of the particles
may have a Gaussian-type distribution. In some embodiments, the
plurality of particles have an average diameter of less than about
300 nm, less than about 250 nm, less than about 200 nm, less than
about 150 nm, less than about 100 nm, less than about 50 nm, less
than about 30 nm, less than about 10 nm, less than about 3 nm, or
less than about 1 nm. In some embodiments, the particles have an
average diameter of at least about 5 nm, at least about 10 nm, at
least about 30 nm, at least about 50 nm, at least about 100 nm, at
least about 150 nm, or greater. In certain embodiments, the
plurality of the particles have an average diameter of about 10 nm,
about 25 nm, about 50 nm, about 100 nm, about 150 nm, about 200 nm,
about 250 nm, about 300 nm, about 500 nm, or the like. In some
embodiments, the plurality of particles have an average diameter
between about 10 nm and about 500 nm, between about 50 nm and about
400 nm, between about 100 nm and about 300 nm, between about 150 nm
and about 250 nm, between about 175 nm and about 225 nm, or the
like. In some embodiments, the plurality of particles have an
average diameter between about 10 nm and about 500 nm, between
about 20 nm and about 400 nm, between about 30 nm and about 300 nm,
between about 40 nm and about 200 nm, between about 50 nm and about
175 nm, between about 60 nm and about 150 nm, between about 70 nm
and about 130 nm, or the like. For example, the average diameter
can be between about 70 nm and 130 nm. In some embodiments, the
plurality of particles have an average diameter between about 20 nm
and about 220 nm, between about 30 nm and about 200 nm, between
about 40 nm and about 180 nm, between about 50 nm and about 170 nm,
between about 60 nm and about 150 nm, or between about 70 nm and
about 130 nm. In one embodiment, the particles have a size of 40 to
120 nm with a zeta potential close to 0 mV at low to zero ionic
strengths (1 to 10 mM), with zeta potential values between +5 to -5
mV, and a zero/neutral or a small -ve surface charge.
A. Conjugates
[0172] The particles contain one or more conjugates as described
above. The conjugates can be present on the interior of the
particle, on the exterior of the particle, or both. The particles
may comprise hydrophobic ion-pairing complexes or hydrophobic
ion-pairs formed by one or more conjugates described above and
counterions.
[0173] Hydrophobic ion-pairing (HIP) is the interaction between a
pair of oppositely charged ions held together by Coulombic
attraction. HIP, as used here in, refers to the interaction between
the conjugate of the present invention and its counterions, wherein
the counterion is not H.sup.+ or HO.sup.- ions. Hydrophobic
ion-pairing complex or hydrophobic ion-pair, as used herein, refers
to the complex formed by the conjugate of the present invention and
its counterions. In some embodiments, the counterions are
hydrophobic. In some embodiments, the counterions are provided by a
hydrophobic acid or a salt of a hydrophobic acid. In some
embodiments, the counterions are provided by bile acids or salts,
fatty acids or salts, lipids, or amino acids. In some embodiments,
the counterions are negatively charged (anionic). Non-limited
examples of negative charged counterions include the counterions
sodium sulfosuccinate (AOT), sodium oleate, sodium dodecyl sulfate
(SDS), human serum albumin (HSA), dextran sulphate, sodium
deoxycholate, sodium cholate, anionic lipids, amino acids, or any
combination thereof. Without wishing to be bound by any theory, in
some embodiments, HIP may increase the hydrophobicity and/or
lipophilicity of the conjugate of the present invention. In some
embodiments, increasing the hydrophobicity and/or lipophilicity of
the conjugate of the present invention may be beneficial for
particle formulations and may provide higher solubility of the
conjugate of the present invention in organic solvents. Without
wishing to be bound by any theory, it is believed that particle
formulations that include HIP pairs have improved formulation
properties, such as drug loading and/or release profile. Without
wishing to be bound by any theory, in some embodiments, slow
release of the conjugate of the invention from the particles may
occur, due to a decrease in the conjugate's solubility in aqueous
solution. In addition, without wishing to be bound by any theory,
complexing the conjugate with large hydrophobic counterions may
slow diffusion of the conjugate within a polymeric matrix. In some
embodiments, HIP occurs without covalent conjuatation of the
counterion to the conjugate of the present invention.
[0174] Without wishing to be bound by any theory, the strength of
HIP may impact the drug load and release rate of the particles of
the invention. In some embodiments, the strength of the HIP may be
increased by increasing the magnitude of the difference between the
pKa of the conjugate of the present invention and the pKa of the
agent providing the counterion. Also without wishing to be bound by
any theory, the conditions for ion pair formation may impact the
drug load and release rate of the particles of the invention.
[0175] In some embodiments, any suitable hydrophobic acid or a
combination thereof may form a HIP pair with the conjugate of the
present invention. In some embodiments, the hydrophobic acid may be
a carboxylic acid (such as but not limited to a monocarboxylic
acid, dicarboxylic acid, tricarboxylic acid), a sulfinic acid, a
sulfenic acid, or a sulfonic acid. In some embodiments, a salt of a
suitable hydrophobic acid or a combination thereof may be used to
form a HIP pair with the conjugate of the present invention.
Examples of hydrophobic acids, saturated fatty acids, unsaturated
fatty acids, aromatic acids, bile acid, polyelectrolyte, their
dissociation constant in water (pKa) and log P values were
disclosed in WO2014/043,625, the contents of which are incorporated
herein by reference in their entirety. The strength of the
hydrophobic acid, the difference between the pKa of the hydrophobic
acid and the pKa of the conjugate of the present invention, log P
of the hydrophobic acid, the phase transition temperature of the
hydrophobic acid, the molar ratio of the hydrophobic acid to the
conjugate of the present invention, and the concentration of the
hydrophobic acid were also disclosed in WO2014/043,625, the
contents of which are incorporated herein by reference in their
entirety.
[0176] In some embodiments, particles of the present invention
comprising a HIP complex and/or prepared by a process that provides
a counterion to form HIP complex with the conjugate may have a
higher drug loading than particles without a HIP complex or
prepared by a process that does not provide any counterion to form
HIP complex with the conjugate. In some embodiments, drug loading
may increase 50%, 100%, 2 times, 3 times, 4 times, 5 times, 6
times, 7 times, 8 times, 9 times, or 10 times.
[0177] In some embodiments, the particles of the invention may
retain the conjugate for at least about 1 minute, at least about 15
minutes, at least about 1 hour, when placed in a phosphate buffer
solution at 37.degree. C.
[0178] In some embodiments, the weight percentage of the conjugate
in the particles is at least about 0.05%, 0.1%, 0.5%, 1%, 5%, 10%,
15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% such that the sum of the
weight percentages of the components of the particles is 100%. In
some embodiments, the weight percentage of the conjugate in the
particles is from about 0.5% to about 10%, or about 10% to about
20%, or about 20% to about 30%, or about 30% to about 40%, or about
40% to about 50%, or about 50% to about 60%, or about 60% to about
70%, or about 70% to about 80%, or about 80% to about 90%, or about
90% to about 99% such that the sum of the weight percentages of the
components of the particles is 100%.
[0179] In some instances, a conjugate may have a molecular weight
of less than about 50,000 Da, less than about 40,000 Da, less than
about 30,000 Da, less than about 20,000 Da, less than about 15,000
Da, less than about 10,000 Da, less than about 8,000 Da, less than
about 5,000 Da, or less than about 3,000 Da. In some cases, the
conjugate may have a molecular weight of between about 1,000 Da and
about 50,000 Da, between about 1,000 Da and about 40,000 Da, in
some embodiments between about 1,000 Da and about 30,000 Da, in
some embodiments bout 1,000 Da and about 50,000 Da, between about
1,000 Da and about 20,000 Da, in some embodiments between about
1,000 Da and about 15,000 Da, in some embodiments between about
1,000 Da and about 10,000 Da, in some embodiments between about
1,000 Da and about 8,000 Da, in some embodiments between about
1,000 Da and about 5,000 Da, and in some embodiments between about
1,000 Da and about 3,000 Da. The molecular weight of the conjugate
may be calculated as the sum of the atomic weight of each atom in
the formula of the conjugate multiplied by the number of each atom.
It may also be measured by mass spectrometry, NMR, chromatography,
light scattering, viscosity, and/or any other methods known in the
art. It is known in the art that the unit of molecular weight may
be g/mol, Dalton (Da), or atomic mass unit (amu), wherein 1 g/mol=1
Da=1 amu.
B. Polymers
[0180] The particles may contain one or more polymers. Polymers may
contain one more of the following polyesters: homopolymers
including glycolic acid units, referred to herein as "PGA", and
lactic acid units, such as poly-L-lactic acid, poly-D-lactic acid,
poly-D,L-lactic acid, poly-L-lactide, poly-D-lactide, and
poly-D,L-lactide, collectively referred to herein as "PLA", and
caprolactone units, such as poly(.epsilon.-caprolactone),
collectively referred to herein as "PCL"; and copolymers including
lactic acid and glycolic acid units, such as various forms of
poly(lactic acid-co-glycolic acid) and poly(lactide-co-glycolide)
characterized by the ratio of lactic acid:glycolic acid,
collectively referred to herein as "PLGA"; and polyacrylates, and
derivatives thereof. Exemplary polymers also include copolymers of
polyethylene glycol (PEG) and the aforementioned polyesters, such
as various forms of PLGA-PEG or PLA-PEG copolymers, collectively
referred to herein as "PEGylated polymers". In certain embodiments,
the PEG region can be covalently associated with polymer to yield
"PEGylated polymers" by a cleavable linker.
[0181] The particles may contain one or more hydrophilic polymers.
Hydrophilic polymers include cellulosic polymers such as starch and
polysaccharides; hydrophilic polypeptides; poly(amino acids) such
as poly-L-glutamic acid (PGS), gamma-polyglutamic acid,
poly-L-aspartic acid, poly-L-serine, or poly-L-lysine; polyalkylene
glycols and polyalkylene oxides such as polyethylene glycol (PEG),
polypropylene glycol (PPG), and poly(ethylene oxide) (PEO);
poly(oxyethylated polyol); poly(olefinic alcohol);
polyvinylpyrrolidone); poly(hydroxyalkylmethacrylamide);
poly(hydroxyalkylmethacrylate); poly(saccharides); poly(hydroxy
acids); poly(vinyl alcohol); polyoxazoline; and copolymers
thereof.
[0182] The particles may contain one or more hydrophobic polymers.
Examples of suitable hydrophobic polymers include polyhydroxyacids
such as poly(lactic acid), poly(glycolic acid), and poly(lactic
acid-co-glycolic acids); polyhydroxyalkanoates such as
poly3-hydroxybutyrate or poly4-hydroxybutyrate; polycaprolactones;
poly(orthoesters); polyanhydrides; poly(phosphazenes);
poly(lactide-co-caprolactones); polycarbonates such as tyrosine
polycarbonates; polyamides (including synthetic and natural
polyamides), polypeptides, and poly(amino acids); polyesteramides;
polyesters; poly(dioxanones); poly(alkylene alkylates); hydrophobic
polyethers; polyurethanes; polyetheresters; polyacetals;
polycyanoacrylates; polyacrylates; polymethylmethacrylates;
polysiloxanes; poly(oxyethylene)/poly(oxypropylene) copolymers;
polyketals; polyphosphates; polyhydroxyvalerates; polyalkylene
oxalates; polyalkylene succinates; poly(maleic acids), as well as
copolymers thereof.
[0183] In certain embodiments, the hydrophobic polymer is an
aliphatic polyester. In some embodiments, the hydrophobic polymer
is poly(lactic acid), poly(glycolic acid), or poly(lactic
acid-co-glycolic acid).
[0184] The particles can contain one or more biodegradable
polymers. Biodegradable polymers can include polymers that are
insoluble or sparingly soluble in water that are converted
chemically or enzymatically in the body into water-soluble
materials. Biodegradable polymers can include soluble polymers
crosslinked by hydolyzable cross-linking groups to render the
crosslinked polymer insoluble or sparingly soluble in water.
[0185] Biodegradable polymers in the particle can include
polyamides, polycarbonates, polyalkylenes, polyalkylene glycols,
polyalkylene oxides, polyalkylene terepthalates, polyvinyl
alcohols, polyvinyl ethers, polyvinyl esters, polyvinyl halides,
polyvinylpyrrolidone, polyglycolides, polysiloxanes, polyurethanes
and copolymers thereof, alkyl cellulose such as methyl cellulose
and ethyl cellulose, hydroxyalkyl celluloses such as hydroxypropyl
cellulose, hydroxy-propyl methyl cellulose, and hydroxybutyl methyl
cellulose, cellulose ethers, cellulose esters, nitro celluloses,
cellulose acetate, cellulose propionate, cellulose acetate
butyrate, cellulose acetate phthalate, carboxylethyl cellulose,
cellulose triacetate, cellulose sulphate sodium salt, polymers of
acrylic and methacrylic esters such as poly (methyl methacrylate),
poly(ethylmethacrylate), poly(butylmethacrylate),
poly(isobutylmethacrylate), poly(hexlmethacrylate),
poly(isodecylmethacrylate), poly(lauryl methacrylate), poly (phenyl
methacrylate), poly(methyl acrylate), poly(isopropyl acrylate),
poly(isobutyl acrylate), poly(octadecyl acrylate), polyethylene,
polypropylene poly(ethylene glycol), poly(ethylene oxide),
poly(ethylene terephthalate), poly(vinyl alcohols), poly(vinyl
acetate, poly vinyl chloride polystyrene and polyvinylpryrrolidone,
derivatives thereof, linear and branched copolymers and block
copolymers thereof, and blends thereof. Exemplary biodegradable
polymers include polyesters, poly(ortho esters), poly(ethylene
imines), poly(caprolactones), poly(hydroxyalkanoates),
poly(hydroxyvalerates), polyanhydrides, poly(acrylic acids),
polyglycolides, poly(urethanes), polycarbonates, polyphosphate
esters, polyphosphazenes, derivatives thereof, linear and branched
copolymers and block copolymers thereof, and blends thereof. In
some embodiments the particle contains biodegradable polyesters or
polyanhydrides such as poly(lactic acid), poly(glycolic acid), and
poly(lactic-co-glycolic acid).
[0186] The particles can contain one or more amphiphilic polymers.
Amphiphilic polymers can be polymers containing a hydrophobic
polymer block and a hydrophilic polymer block. The hydrophobic
polymer block can contain one or more of the hydrophobic polymers
above or a derivative or copolymer thereof. The hydrophilic polymer
block can contain one or more of the hydrophilic polymers above or
a derivative or copolymer thereof. In some embodiments the
amphiphilic polymer is a di-block polymer containing a hydrophobic
end formed from a hydrophobic polymer and a hydrophilic end formed
of a hydrophilic polymer. In some embodiments, a moiety can be
attached to the hydrophobic end, to the hydrophilic end, or both.
The particle can contain two or more amphiphilic polymers.
C. Lipids
[0187] The particles may contain one or more lipids or amphiphilic
compounds. For example, the particles can be liposomes, lipid
micelles, solid lipid particles, or lipid-stabilized polymeric
particles. The lipid particle can be made from one or a mixture of
different lipids. Lipid particles are formed from one or more
lipids, which can be neutral, anionic, or cationic at physiologic
pH. The lipid particle, in some embodiments, incorporates one or
more biocompatible lipids. The lipid particles may be formed using
a combination of more than one lipid. For example, a charged lipid
may be combined with a lipid that is non-ionic or uncharged at
physiological pH.
[0188] The particle can be a lipid micelle. Lipid micelles for drug
delivery are known in the art. Lipid micelles can be formed, for
instance, as a water-in-oil emulsion with a lipid surfactant. An
emulsion is a blend of two immiscible phases wherein a surfactant
is added to stabilize the dispersed droplets. In some embodiments
the lipid micelle is a microemulsion. A microemulsion is a
thermodynamically stable system composed of at least water, oil and
a lipid surfactant producing a transparent and thermodynamically
stable system whose droplet size is less than 1 micron, from about
10 nm to about 500 nm, or from about 10 nm to about 250 nm. Lipid
micelles are generally useful for encapsulating hydrophobic active
agents, including hydrophobic therapeutic agents, hydrophobic
prophylactic agents, or hydrophobic diagnostic agents.
[0189] The particle can be a liposome. Liposomes are small vesicles
composed of an aqueous medium surrounded by lipids arranged in
spherical bilayers. Liposomes can be classified as small
unilamellar vesicles, large unilamellar vesicles, or multi-lamellar
vesicles. Multi-lamellar liposomes contain multiple concentric
lipid bilayers. Liposomes can be used to encapsulate agents, by
trapping hydrophilic agents in the aqueous interior or between
bilayers, or by trapping hydrophobic agents within the bilayer.
[0190] The lipid micelles and liposomes typically have an aqueous
center. The aqueous center can contain water or a mixture of water
and alcohol. Suitable alcohols include, but are not limited to,
methanol, ethanol, propanol, (such as isopropanol), butanol (such
as n-butanol, isobutanol, sec-butanol, tert-butanol, pentanol (such
as amyl alcohol, isobutyl carbinol), hexanol (such as 1-hexanol,
2-hexanol, 3-hexanol), heptanol (such as 1-heptanol, 2-heptanol,
3-heptanol and 4-heptanol) or octanol (such as 1-octanol) or a
combination thereof.
[0191] The particle can be a solid lipid particle. Solid lipid
particles present an alternative to the colloidal micelles and
liposomes. Solid lipid particles are typically submicron in size,
i.e. from about 10 nm to about 1 micron, from 10 nm to about 500
nm, or from 10 nm to about 250 nm. Solid lipid particles are formed
of lipids that are solids at room temperature. They are derived
from oil-in-water emulsions, by replacing the liquid oil by a solid
lipid.
[0192] Suitable neutral and anionic lipids include, but are not
limited to, sterols and lipids such as cholesterol, phospholipids,
lysolipids, lysophospholipids, sphingolipids or pegylated lipids.
Neutral and anionic lipids include, but are not limited to,
phosphatidylcholine (PC) (such as egg PC, soy PC), including
1,2-diacyl-glycero-3-phosphocholines; phosphatidylserine (PS),
phosphatidylglycerol, phosphatidylinositol (PI); glycolipids;
sphingophospholipids such as sphingomyelin and sphingoglycolipids
(also known as 1-ceramidyl glucosides) such as ceramide
galactopyranoside, gangliosides and cerebrosides; fatty acids,
sterols, containing a carboxylic acid group for example,
cholesterol; 1,2-diacyl-sn-glycero-3-phosphoethanolamine,
including, but not limited to, 1,2-dioleylphosphoethanolamine
(DOPE), 1,2-dihexadecylphosphoethanolamine (DHPE),
1,2-distearoylphosphatidylcholine (DSPC), 1,2-dipalmitoyl
phosphatidylcholine (DPPC), and 1,2-dimyristoylphosphatidylcholine
(DMPC). The lipids can also include various natural (e.g., tissue
derived L-.alpha.-phosphatidyl: egg yolk, heart, brain, liver,
soybean) and/or synthetic (e.g., saturated and unsaturated
1,2-diacyl-sn-glycero-3-phosphocholines,
1-acyl-2-acyl-sn-glycero-3-phosphocholines,
1,2-diheptanoyl-SN-glycero-3-phosphocholine) derivatives of the
lipids.
[0193] Suitable cationic lipids include, but are not limited to,
N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethyl ammonium salts, also
references as TAP lipids, for example methylsulfate salt. Suitable
TAP lipids include, but are not limited to, DOTAP (dioleoyl-),
DMTAP (dimyristoyl-), DPTAP (dipalmitoyl-), and DSTAP
(distearoyl-). Suitable cationic lipids in the liposomes include,
but are not limited to, dimethyldioctadecyl ammonium bromide
(DDAB), 1,2-diacyloxy-3-trimethylammonium propanes,
N-[1-(2,3-dioloyloxy)propyl]-N,N-dimethyl amine (DODAP),
1,2-diacyloxy-3-dimethylammonium propanes,
N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride
(DOTMA), 1,2-dialkyloxy-3-dimethylammonium propanes,
dioctadecylamidoglycylspermine (DOGS),
3-[N--(N',N'-dimethylamino-ethane)carbamoyl] cholesterol (DC-Chol);
2,3-dioleoyloxy-N-(2-(sperminecarboxamido)-ethyl)-N,N-dimethyl-1-propanam-
inium trifluoro-acetate (DOSPA), .beta.-alanyl cholesterol, cetyl
trimethyl ammonium bromide (CTAB), diC.sub.14-amidine,
N-ferf-butyl-N'-tetradecyl-3-tetradecylamino-propionamidine,
N-(alpha-trimethylammonioacetyl)didodecyl-D-glutamate chloride
(TMAG), ditetradecanoyl-N-(trimethylammonio-acetyl)diethanolamine
chloride, 1,3-dioleoyloxy-2-(6-carboxy-spermyl)-propylamide
(DOSPER), and N, N, N', N'-tetramethyl-,
N'-bis(2-hydroxylethyl)-2,3-dioleoyloxy-1,4-butanediammonium
iodide. In one embodiment, the cationic lipids can be
1-[2-(acyloxy)ethyl]2-alkyl(alkenyl)-3-(2-hydroxyethyl)-imidazolinium
chloride derivatives, for example,
1-[2-(9(Z)-octadecenoyloxy)ethyl]-2-(8(Z)-heptadecenyl-3-(2-hydroxyethyl)-
imidazolinium chloride (DOTIM), and
1-[2-(hexadecanoyloxy)ethyl]-2-pentadecyl-3-(2-hydroxyethyl)imidazolinium
chloride (DPTIM). In one embodiment, the cationic lipids can be
2,3-dialkyloxypropyl quaternary ammonium compound derivatives
containing a hydroxyalkyl moiety on the quaternary amine, for
example, 1,2-dioleoyl-3-dimethyl-hydroxyethyl ammonium bromide
(DORI), 1,2-dioleyloxypropyl-3-dimethyl-hydroxyethyl ammonium
bromide (DORIE), 1,2-dioleyloxypropyl-3-dimetyl-hydroxypropyl
ammonium bromide (DORIE-HP),
1,2-dioleyl-oxy-propyl-3-dimethyl-hydroxybutyl ammonium bromide
(DORIE-HB), 1,2-dioleyloxypropyl-3-dimethyl-hydroxypentyl ammonium
bromide (DORIE-Hpe),
1,2-dimyristyloxypropyl-3-dimethyl-hydroxylethyl ammonium bromide
(DMRIE), 1,2-dipalmityloxypropyl-3-dimethyl-hydroxyethyl ammonium
bromide (DPRIE), and 1,2-disteryloxypropyl-3-dimethyl-hydroxyethyl
ammonium bromide (DSRIE).
[0194] Suitable solid lipids include, but are not limited to,
higher saturated alcohols, higher fatty acids, sphingolipids,
synthetic esters, and mono-, di-, and triglycerides of higher
saturated fatty acids. Solid lipids can include aliphatic alcohols
having 10-40, for example, 12-30 carbon atoms, such as cetostearyl
alcohol. Solid lipids can include higher fatty acids of 10-40, for
example, 12-30 carbon atoms, such as stearic acid, palmitic acid,
decanoic acid, and behenic acid. Solid lipids can include
glycerides, including monoglycerides, diglycerides, and
triglycerides, of higher saturated fatty acids having 10-40, for
example, 12-30 carbon atoms, such as glyceryl monostearate,
glycerol behenate, glycerol palmitostearate, glycerol trilaurate,
tricaprin, trilaurin, trimyristin, tripalmitin, tristearin, and
hydrogenated castor oil. Suitable solid lipids can include cetyl
palmitate, beeswax, or cyclodextrin.
[0195] Amphiphilic compounds include, but are not limited to,
phospholipids, such as 1,2
distearoyl-sn-glycero-3-phosphoethanolamine (DSPE),
dipalmitoylphosphatidylcholine (DPPC),
distearoylphosphatidylcholine (DSPC),
diarachidoylphosphatidylcholine (DAPC),
dibehenoylphosphatidylcholine (DBPC),
ditricosanoylphosphatidylcholine (DTPC), and
dilignoceroylphatidylcholine (DLPC), incorporated at a ratio of
between 0.01-60 (weight lipid/w polymer), for example, between
0.1-30 (weight lipid/w polymer). Phospholipids that may be used
include, but are not limited to, phosphatidic acids, phosphatidyl
cholines with both saturated and unsaturated lipids, phosphatidyl
ethanolamines, phosphatidylglycerols, phosphatidylserines,
phosphatidylinositols, lysophosphatidyl derivatives, cardiolipin,
and .beta.-acyl-y-alkyl phospholipids. Examples of phospholipids
include, but are not limited to, phosphatidylcholines such as
dioleoylphosphatidylcholine, dimyristoylphosphatidylcholine,
dipentadecanoylphosphatidylcholine dilauroylphosphatidylcholine,
dipalmitoylphosphatidylcholine (DPPC),
distearoylphosphatidylcholine (DSPC),
diarachidoylphosphatidylcholine (DAPC),
dibehenoylphosphatidylcho-line (DBPC),
ditricosanoylphosphatidylcholine (DTPC),
dilignoceroylphatidylcholine (DLPC); and phosphatidylethanolamines
such as dioleoylphosphatidylethanolamine or
1-hexadecyl-2-palmitoylglycerophos-phoethanolamine. Synthetic
phospholipids with asymmetric acyl chains (e.g., with one acyl
chain of 6 carbons and another acyl chain of 12 carbons) may also
be used.
D. Additional Active Agents
[0196] The particles can contain one or more additional active
agents in addition to those in the conjugates. The additional
active agents can be therapeutic, prophylactic, diagnostic, or
nutritional agents as listed above. The additional active agents
can be present in any amount, e.g. from about 0.5% to about 90%,
from about 0.5% to about 50%, from about 0.5% to about 25%, from
about 0.5% to about 20%, from about 0.5% to about 10%, or from
about 5% to about 10% (w/w) based upon the weight of the particle.
In one embodiment, the agents are incorporated in an about 0.5% to
about 10% loading w/w.
E. Additional Targeting Moieties
[0197] The particles can contain one or more targeting moieties
targeting the particle to a specific organ, tissue, cell type, or
subcellular compartment in addition to the targeting moieties of
the conjugate. The additional targeting moieties can be present on
the surface of the particle, on the interior of the particle, or
both. The additional targeting moieties can be immobilized on the
surface of the particle, e.g., can be covalently attached to
polymer or lipid in the particle. In some embodiments, the
additional targeting moieties are covalently attached to an
amphiphilic polymer or a lipid such that the targeting moieties are
oriented on the surface of the particle.
III. Formulations
[0198] In some embodiments, compositions are administered to
humans, human patients or subjects. For the purposes of the present
disclosure, the phrase "active ingredient" generally refers to the
conjugate or particles comprising the conjugates to be delivered as
described herein.
[0199] Although the descriptions of pharmaceutical compositions
provided herein are principally directed to pharmaceutical
compositions which are suitable for administration to humans, it
will be understood by the skilled artisan that such compositions
are generally suitable for administration to any other animal,
e.g., to non-human animals, e.g. non-human mammals. Modification of
pharmaceutical compositions suitable for administration to humans
in order to render the compositions suitable for administration to
various animals is well understood, and the ordinarily skilled
veterinary pharmacologist can design and/or perform such
modification with merely ordinary, if any, experimentation.
Subjects to which administration of the pharmaceutical compositions
is contemplated include, but are not limited to, humans and/or
other primates; mammals, including commercially relevant mammals
such as cattle, pigs, horses, sheep, cats, dogs, mice, and/or rats;
and/or birds, including commercially relevant birds such as
poultry, chickens, ducks, geese, and/or turkeys.
[0200] Formulations of the pharmaceutical compositions described
herein may be prepared by any method known or hereafter developed
in the art of pharmacology. In general, such preparatory methods
include the step of bringing the active ingredient into association
with an excipient and/or one or more other accessory ingredients,
and then, if necessary and/or desirable, dividing, shaping and/or
packaging the product into a desired single- or multi-dose
unit.
[0201] A pharmaceutical composition in accordance with the
invention may be prepared, packaged, and/or sold in bulk, as a
single unit dose, and/or as a plurality of single unit doses. As
used herein, a "unit dose" is discrete amount of the pharmaceutical
composition comprising a predetermined amount of the active
ingredient. The amount of the active ingredient is generally equal
to the dosage of the active ingredient which would be administered
to a subject and/or a convenient fraction of such a dosage such as,
for example, one-half or one-third of such a dosage.
[0202] Relative amounts of the active ingredient, the
pharmaceutically acceptable excipient, and/or any additional
ingredients in a pharmaceutical composition in accordance with the
invention will vary, depending upon the identity, size, and/or
condition of the subject treated and further depending upon the
route by which the composition is to be administered. By way of
example, the composition may comprise between 0.1% and 100%, e.g.,
between 0.5 and 50%, between 1-30%, between 5-80%, at least 80%
(w/w) active ingredient.
[0203] The conjugates or particles of the present invention can be
formulated using one or more excipients to: (1) increase stability;
(2) permit the sustained or delayed release (e.g., from a depot
formulation of the monomaleimide); (3) alter the biodistribution
(e.g., target the monomaleimide compounds to specific tissues or
cell types); (4) alter the release profile of the monomaleimide
compounds in vivo. Non-limiting examples of the excipients include
any and all solvents, dispersion media, diluents, or other liquid
vehicles, dispersion or suspension aids, surface active agents,
isotonic agents, thickening or emulsifying agents, and
preservatives. Excipients of the present invention may also
include, without limitation, lipidoids, liposomes, lipid
nanoparticles, polymers, lipoplexes, core-shell nanoparticles,
peptides, proteins, hyaluronidase, nanoparticle mimics and
combinations thereof. Accordingly, the formulations of the
invention may include one or more excipients, each in an amount
that together increases the stability of the monomaleimide
compounds.
Excipients
[0204] Pharmaceutical formulations may additionally comprise a
pharmaceutically acceptable excipient, which, as used herein,
includes any and all solvents, dispersion media, diluents, or other
liquid vehicles, dispersion or suspension aids, surface active
agents, isotonic agents, thickening or emulsifying agents,
preservatives, solid binders, lubricants and the like, as suited to
the particular dosage form desired. Remington's The Science and
Practice of Pharmacy, 21st Edition, A. R. Gennaro (Lippincott,
Williams & Wilkins, Baltimore, Md., 2006; incorporated herein
by reference in its entirety) discloses various excipients used in
formulating pharmaceutical compositions and known techniques for
the preparation thereof. Except insofar as any conventional
excipient medium is incompatible with a substance or its
derivatives, such as by producing any undesirable biological effect
or otherwise interacting in a deleterious manner with any other
component(s) of the pharmaceutical composition, its use is
contemplated to be within the scope of this invention.
[0205] In some embodiments, a pharmaceutically acceptable excipient
is at least 95%, at least 96%, at least 97%, at least 98%, at least
99%, or 100% pure. In some embodiments, an excipient is approved
for use in humans and for veterinary use. In some embodiments, an
excipient is approved by United States Food and Drug
Administration. In some embodiments, an excipient is pharmaceutical
grade. In some embodiments, an excipient meets the standards of the
United States Pharmacopoeia (USP), the European Pharmacopoeia (EP),
the British Pharmacopoeia, and/or the International
Pharmacopoeia.
[0206] Pharmaceutically acceptable excipients used in the
manufacture of pharmaceutical compositions include, but are not
limited to, inert diluents, dispersing and/or granulating agents,
surface active agents and/or emulsifiers, disintegrating agents,
binding agents, preservatives, buffering agents, lubricating
agents, and/or oils. Such excipients may optionally be included in
pharmaceutical compositions.
[0207] Exemplary diluents include, but are not limited to, calcium
carbonate, sodium carbonate, calcium phosphate, dicalcium
phosphate, calcium sulfate, calcium hydrogen phosphate, sodium
phosphate lactose, sucrose, cellulose, microcrystalline cellulose,
kaolin, mannitol, sorbitol, inositol, sodium chloride, dry starch,
cornstarch, powdered sugar, etc., and/or combinations thereof.
[0208] Exemplary granulating and/or dispersing agents include, but
are not limited to, potato starch, corn starch, tapioca starch,
sodium starch glycolate, clays, alginic acid, guar gum, citrus
pulp, agar, bentonite, cellulose and wood products, natural sponge,
cation-exchange resins, calcium carbonate, silicates, sodium
carbonate, cross-linked poly(vinyl-pyrrolidone) (crospovidone),
sodium carboxymethyl starch (sodium starch glycolate),
carboxymethyl cellulose, cross-linked sodium carboxymethyl
cellulose (croscarmellose), methylcellulose, pregelatinized starch
(starch 1500), microcrystalline starch, water insoluble starch,
calcium carboxymethyl cellulose, magnesium aluminum silicate
(VEEGUM.RTM.), sodium lauryl sulfate, quaternary ammonium
compounds, etc., and/or combinations thereof.
[0209] Exemplary surface active agents and/or emulsifiers include,
but are not limited to, natural emulsifiers (e.g. acacia, agar,
alginic acid, sodium alginate, tragacanth, chondrux, cholesterol,
xanthan, pectin, gelatin, egg yolk, casein, wool fat, cholesterol,
wax, and lecithin), colloidal clays (e.g. bentonite [aluminum
silicate] and VEEGUM.RTM. [magnesium aluminum silicate]), long
chain amino acid derivatives, high molecular weight alcohols (e.g.
stearyl alcohol, cetyl alcohol, oleyl alcohol, triacetin
monostearate, ethylene glycol distearate, glyceryl monostearate,
and propylene glycol monostearate, polyvinyl alcohol), carbomers
(e.g. carboxy polymethylene, polyacrylic acid, acrylic acid
polymer, and carboxyvinyl polymer), carrageenan, cellulosic
derivatives (e.g. carboxymethylcellulose sodium, powdered
cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose,
hydroxypropyl methylcellulose, methylcellulose), sorbitan fatty
acid esters (e.g. polyoxyethylene sorbitan monolaurate
[TWEEN.RTM.20], polyoxyethylene sorbitan [TWEENn.RTM.60],
polyoxyethylene sorbitan monooleate [TWEEN.RTM.80], sorbitan
monopalmitate [SPAN.RTM.40], sorbitan monostearate [SPAN.RTM.60],
sorbitan tristearate [SPAN.RTM.65], glyceryl monooleate, sorbitan
monooleate [SPAN.RTM.80]), polyoxyethylene esters (e.g.
polyoxyethylene monostearate [MYRJ.RTM.45], polyoxyethylene
hydrogenated castor oil, polyethoxylated castor oil,
polyoxymethylene stearate, and SOLUTOL.RTM.), sucrose fatty acid
esters, polyethylene glycol fatty acid esters (e.g.
CREMOPHOR.RTM.), polyoxyethylene ethers, (e.g. polyoxyethylene
lauryl ether [BRIJ.RTM.30]), poly(vinyl-pyrrolidone), diethylene
glycol monolaurate, triethanolamine oleate, sodium oleate,
potassium oleate, ethyl oleate, oleic acid, ethyl laurate, sodium
lauryl sulfate, PLUORINC.RTM. F 68, POLOXAMER.RTM.188, cetrimonium
bromide, cetylpyridinium chloride, benzalkonium chloride, docusate
sodium, etc. and/or combinations thereof.
[0210] Exemplary binding agents include, but are not limited to,
starch (e.g. cornstarch and starch paste); gelatin; sugars (e.g.
sucrose, glucose, dextrose, dextrin, molasses, lactose, lactitol,
mannitol); natural and synthetic gums (e.g. acacia, sodium
alginate, extract of Irish moss, panwar gum, ghatti gum, mucilage
of isapol husks, carboxymethylcellulose, methylcellulose,
ethylcellulose, hydroxyethylcellulose, hydroxypropyl cellulose,
hydroxypropyl methylcellulose, microcrystalline cellulose,
cellulose acetate, poly(vinyl-pyrrolidone), magnesium aluminum
silicate (Veegum.RTM.), and larch arabogalactan); alginates;
polyethylene oxide; polyethylene glycol; inorganic calcium salts;
silicic acid; polymethacrylates; waxes; water; alcohol; etc.; and
combinations thereof.
[0211] Exemplary preservatives may include, but are not limited to,
antioxidants, chelating agents, antimicrobial preservatives,
antifungal preservatives, alcohol preservatives, acidic
preservatives, and/or other preservatives. Exemplary antioxidants
include, but are not limited to, alpha tocopherol, ascorbic acid,
acorbyl palmitate, butylated hydroxyanisole, butylated
hydroxytoluene, monothioglycerol, potassium metabisulfite,
propionic acid, propyl gallate, sodium ascorbate, sodium bisulfite,
sodium metabisulfite, and/or sodium sulfite. Exemplary chelating
agents include ethylenediaminetetraacetic acid (EDTA), citric acid
monohydrate, disodium edetate, dipotassium edetate, edetic acid,
fumaric acid, malic acid, phosphoric acid, sodium edetate, tartaric
acid, and/or trisodium edetate. Exemplary antimicrobial
preservatives include, but are not limited to, benzalkonium
chloride, benzethonium chloride, benzyl alcohol, bronopol,
cetrimide, cetylpyridinium chloride, chlorhexidine, chlorobutanol,
chlorocresol, chloroxylenol, cresol, ethyl alcohol, glycerin,
hexetidine, imidurea, phenol, phenoxyethanol, phenylethyl alcohol,
phenylmercuric nitrate, propylene glycol, and/or thimerosal.
Exemplary antifungal preservatives include, but are not limited to,
butyl paraben, methyl paraben, ethyl paraben, propyl paraben,
benzoic acid, hydroxybenzoic acid, potassium benzoate, potassium
sorbate, sodium benzoate, sodium propionate, and/or sorbic acid.
Exemplary alcohol preservatives include, but are not limited to,
ethanol, polyethylene glycol, phenol, phenolic compounds,
bisphenol, chlorobutanol, hydroxybenzoate, and/or phenylethyl
alcohol. Exemplary acidic preservatives include, but are not
limited to, vitamin A, vitamin C, vitamin E, beta-carotene, citric
acid, acetic acid, dehydroacetic acid, ascorbic acid, sorbic acid,
and/or phytic acid. Other preservatives include, but are not
limited to, tocopherol, tocopherol acetate, deteroxime mesylate,
cetrimide, butylated hydroxyanisol (BHA), butylated hydroxytoluened
(BHT), ethylenediamine, sodium lauryl sulfate (SLS), sodium lauryl
ether sulfate (SLES), sodium bisulfite, sodium metabisulfite,
potassium sulfite, potassium metabisulfite, GLYDANT PLUS.RTM.,
PHENONIP.RTM., methylparaben, GERMALL.RTM.115, GERMABEN.RTM. II,
NEOLONE.TM., KATHON.TM., and/or EUXYL.RTM..
[0212] Exemplary buffering agents include, but are not limited to,
citrate buffer solutions, acetate buffer solutions, phosphate
buffer solutions, ammonium chloride, calcium carbonate, calcium
chloride, calcium citrate, calcium glubionate, calcium gluceptate,
calcium gluconate, D-gluconic acid, calcium glycerophosphate,
calcium lactate, propanoic acid, calcium levulinate, pentanoic
acid, dibasic calcium phosphate, phosphoric acid, tribasic calcium
phosphate, calcium hydroxide phosphate, potassium acetate,
potassium chloride, potassium gluconate, potassium mixtures,
dibasic potassium phosphate, monobasic potassium phosphate,
potassium phosphate mixtures, sodium acetate, sodium bicarbonate,
sodium chloride, sodium citrate, sodium lactate, dibasic sodium
phosphate, monobasic sodium phosphate, sodium phosphate mixtures,
tromethamine, magnesium hydroxide, aluminum hydroxide, alginic
acid, pyrogen-free water, isotonic saline, Ringer's solution, ethyl
alcohol, etc., and/or combinations thereof.
[0213] Exemplary lubricating agents include, but are not limited
to, magnesium stearate, calcium stearate, stearic acid, silica,
talc, malt, glyceryl behanate, hydrogenated vegetable oils,
polyethylene glycol, sodium benzoate, sodium acetate, sodium
chloride, leucine, magnesium lauryl sulfate, sodium lauryl sulfate,
etc., and combinations thereof.
[0214] Exemplary oils include, but are not limited to, almond,
apricot kernel, avocado, babassu, bergamot, black current seed,
borage, cade, camomile, canola, caraway, carnauba, castor,
cinnamon, cocoa butter, coconut, cod liver, coffee, corn, cotton
seed, emu, eucalyptus, evening primrose, fish, flaxseed, geraniol,
gourd, grape seed, hazel nut, hyssop, isopropyl myristate, jojoba,
kukui nut, lavandin, lavender, lemon, litsea cubeba, macademia nut,
mallow, mango seed, meadowfoam seed, mink, nutmeg, olive, orange,
orange roughy, palm, palm kernel, peach kernel, peanut, poppy seed,
pumpkin seed, rapeseed, rice bran, rosemary, safflower, sandalwood,
sasquana, savoury, sea buckthorn, sesame, shea butter, silicone,
soybean, sunflower, tea tree, thistle, tsubaki, vetiver, walnut,
and wheat germ oils. Exemplary oils include, but are not limited
to, butyl stearate, caprylic triglyceride, capric triglyceride,
cyclomethicone, diethyl sebacate, dimethicone 360, isopropyl
myristate, mineral oil, octyldodecanol, oleyl alcohol, silicone
oil, and/or combinations thereof.
[0215] Excipients such as cocoa butter and suppository waxes,
coloring agents, coating agents, sweetening, flavoring, and/or
perfuming agents can be present in the composition, according to
the judgment of the formulator.
Administration
[0216] The conjugates or particles of the present invention may be
administered by any route which results in a therapeutically
effective outcome. These include, but are not limited to enteral,
gastroenteral, epidural, oral, transdermal, epidural (peridural),
intracerebral (into the cerebrum), intracerebroventricular (into
the cerebral ventricles), epicutaneous (application onto the skin),
intradermal, (into the skin itself), subcutaneous (under the skin),
nasal administration (through the nose), intravenous (into a vein),
intraarterial (into an artery), intramuscular (into a muscle),
intracardiac (into the heart), intraosseous infusion (into the bone
marrow), intrathecal (into the spinal canal), intraperitoneal,
(infusion or injection into the peritoneum), intravesical infusion,
intravitreal, (through the eye), intracavernous injection, (into
the base of the penis), intravaginal administration, intrauterine,
extra-amniotic administration, transdermal (diffusion through the
intact skin for systemic distribution), transmucosal (diffusion
through a mucous membrane), insufflation (snorting), sublingual,
sublabial, enema, eye drops (onto the conjunctiva), or in ear
drops. In specific embodiments, compositions may be administered in
a way which allows them cross the blood-brain barrier, vascular
barrier, or other epithelial barrier.
[0217] The formulations described herein contain an effective
amount of conjugates or particles in a pharmaceutical carrier
appropriate for administration to an individual in need thereof.
The formulations may be administered parenterally (e.g., by
injection or infusion). The formulations or variations thereof may
be administered in any manner including enterally, topically (e.g.,
to the eye), or via pulmonary administration. In some embodiments
the formulations are administered topically.
A. Parenteral Formulations
[0218] The conjugates or particles can be formulated for parenteral
delivery, such as injection or infusion, in the form of a solution,
suspension or emulsion. The formulation can be administered
systemically, regionally or directly to the organ or tissue to be
treated.
[0219] Parenteral formulations can be prepared as aqueous
compositions using techniques is known in the art. Typically, such
compositions can be prepared as injectable formulations, for
example, solutions or suspensions; solid forms suitable for using
to prepare solutions or suspensions upon the addition of a
reconstitution medium prior to injection; emulsions, such as
water-in-oil (w/o) emulsions, oil-in-water (o/w) emulsions, and
microemulsions thereof, liposomes, or emulsomes.
[0220] The carrier can be a solvent or dispersion medium
containing, for example, water, ethanol, one or more polyols (e.g.,
glycerol, propylene glycol, and liquid polyethylene glycol), oils,
such as vegetable oils (e.g., peanut oil, corn oil, sesame oil,
etc.), and combinations thereof. The proper fluidity can be
maintained, for example, by the use of a coating, such as lecithin,
by the maintenance of the required particle size in the case of
dispersion and/or by the use of surfactants. In some cases, an
isotonic agent is included, for example, one or more sugars, sodium
chloride, or other suitable agent known in the art.
[0221] Solutions and dispersions of the conjugates or particles can
be prepared in water or another solvent or dispersing medium
suitably mixed with one or more pharmaceutically acceptable
excipients including, but not limited to, surfactants, dispersants,
emulsifiers, pH modifying agents, and combinations thereof.
[0222] Suitable surfactants may be anionic, cationic, amphoteric or
nonionic surface active agents. Suitable anionic surfactants
include, but are not limited to, those containing carboxylate,
sulfonate and sulfate ions. Examples of anionic surfactants include
sodium, potassium, ammonium of long chain alkyl sulfonates and
alkyl aryl sulfonates such as sodium dodecylbenzene sulfonate;
dialkyl sodium sulfosuccinates, such as sodium dodecylbenzene
sulfonate; dialkyl sodium sulfosuccinates, such as sodium
bis-(2-ethylthioxyl)-sulfosuccinate; and alkyl sulfates such as
sodium lauryl sulfate. Cationic surfactants include, but are not
limited to, quaternary ammonium compounds such as benzalkonium
chloride, benzethonium chloride, cetrimonium bromide, stearyl
dimethylbenzyl ammonium chloride, polyoxyethylene and coconut
amine. Examples of nonionic surfactants include ethylene glycol
monostearate, propylene glycol myristate, glyceryl monostearate,
glyceryl stearate, polyglyceryl-4-oleate, sorbitan acylate, sucrose
acylate, PEG-150 laurate, PEG-400 monolaurate, polyoxyethylene
monolaurate, polysorbates, polyoxyethylene octylphenylether,
PEG-1000 cetyl ether, polyoxyethylene tridecyl ether, polypropylene
glycol butyl ether, Poloxamer.RTM. 401, stearoyl
monoisopropanolamide, and polyoxyethylene hydrogenated tallow
amide. Examples of amphoteric surfactants include sodium
N-dodecyl-.beta.-alanine, sodium N-lauryl-.beta.-iminodipropionate,
myristoamphoacetate, lauryl betaine and lauryl sulfobetaine.
[0223] The formulation can contain a preservative to prevent the
growth of microorganisms. Suitable preservatives include, but are
not limited to, parabens, chlorobutanol, phenol, sorbic acid, and
thimerosal. The formulation may also contain an antioxidant to
prevent degradation of the active agent(s) or particles.
[0224] The formulation is typically buffered to a pH of 3-8 for
parenteral administration upon reconstitution. Suitable buffers
include, but are not limited to, phosphate buffers, acetate
buffers, and citrate buffers. If using 10% sucrose or 5% dextrose,
a buffer may not be required.
[0225] Water soluble polymers are often used in formulations for
parenteral administration. Suitable water-soluble polymers include,
but are not limited to, polyvinylpyrrolidone, dextran,
carboxymethylcellulose, and polyethylene glycol.
[0226] Sterile injectable solutions can be prepared by
incorporating the conjugates or particles in the required amount in
the appropriate solvent or dispersion medium with one or more of
the excipients listed above, as required, followed by filtered
sterilization. Generally, dispersions are prepared by incorporating
the various sterilized conjugates or particles into a sterile
vehicle which contains the basic dispersion medium and the required
other ingredients from those listed above. In the case of sterile
powders for the preparation of sterile injectable solutions,
examples of methods of preparation include vacuum-drying and
freeze-drying techniques that yield a powder of the particle plus
any additional desired ingredient from a previously
sterile-filtered solution thereof. The powders can be prepared in
such a manner that the particles are porous in nature, which can
increase dissolution of the particles. Methods for making porous
particles are known in the art.
[0227] Pharmaceutical formulations for parenteral administration
can be in the form of a sterile aqueous solution or suspension of
conjugates or particles formed from one or more polymer-drug
conjugates. Acceptable solvents include, for example, water,
Ringer's solution, phosphate buffered saline (PBS), and isotonic
sodium chloride solution. The formulation may also be a sterile
solution, suspension, or emulsion in a nontoxic, parenterally
acceptable diluent or solvent such as 1,3-butanediol.
[0228] In some instances, the formulation is distributed or
packaged in a liquid form. Alternatively, formulations for
parenteral administration can be packed as a solid, obtained, for
example by lyophilization of a suitable liquid formulation. The
solid can be reconstituted with an appropriate carrier or diluent
prior to administration.
[0229] Solutions, suspensions, or emulsions for parenteral
administration may be buffered with an effective amount of buffer
necessary to maintain a pH suitable for ocular administration.
Suitable buffers are well known by those skilled in the art and
some examples of useful buffers are acetate, borate, carbonate,
citrate, and phosphate buffers.
[0230] Solutions, suspensions, or emulsions for parenteral
administration may also contain one or more tonicity agents to
adjust the isotonic range of the formulation. Suitable tonicity
agents are well known in the art and some examples include
glycerin, sucrose, dextrose, mannitol, sorbitol, sodium chloride,
and other electrolytes.
[0231] Solutions, suspensions, or emulsions for parenteral
administration may also contain one or more preservatives to
prevent bacterial contamination of the ophthalmic preparations.
Suitable preservatives are known in the art, and include
polyhexamethylenebiguanidine (PHMB), benzalkonium chloride (BAK),
stabilized oxychloro complexes (otherwise known as Purite.RTM.),
phenylmercuric acetate, chlorobutanol, sorbic acid, chlorhexidine,
benzyl alcohol, parabens, thimerosal, and mixtures thereof.
[0232] Solutions, suspensions, or emulsions for parenteral
administration may also contain one or more excipients known art,
such as dispersing agents, wetting agents, and suspending
agents.
B. Mucosal Topical Formulations
[0233] The conjugates or particles can be formulated for topical
administration to a mucosal surface Suitable dosage forms for
topical administration include creams, ointments, salves, sprays,
gels, lotions, emulsions, liquids, and transdermal patches. The
formulation may be formulated for transmucosal transepithelial, or
transendothelial administration. The compositions contain one or
more chemical penetration enhancers, membrane permeability agents,
membrane transport agents, emollients, surfactants, stabilizers,
and combination thereof. In some embodiments, the conjugates or
particles can be administered as a liquid formulation, such as a
solution or suspension, a semi-solid formulation, such as a lotion
or ointment, or a solid formulation. In some embodiments, the
conjugates or particles are formulated as liquids, including
solutions and suspensions, such as eye drops or as a semi-solid
formulation, to the mucosa, such as the eye or vaginally or
rectally.
[0234] "Surfactants" are surface-active agents that lower surface
tension and thereby increase the emulsifying, foaming, dispersing,
spreading and wetting properties of a product. Suitable non-ionic
surfactants include emulsifying wax, glyceryl monooleate,
polyoxyethylene alkyl ethers, polyoxyethylene castor oil
derivatives, polysorbate, sorbitan esters, benzyl alcohol, benzyl
benzoate, cyclodextrins, glycerin monostearate, poloxamer, povidone
and combinations thereof. In one embodiment, the non-ionic
surfactant is stearyl alcohol.
[0235] "Emulsifiers" are surface active substances which promote
the suspension of one liquid in another and promote the formation
of a stable mixture, or emulsion, of oil and water. Common
emulsifiers are: metallic soaps, certain animal and vegetable oils,
and various polar compounds. Suitable emulsifiers include acacia,
anionic emulsifying wax, calcium stearate, carbomers, cetostearyl
alcohol, cetyl alcohol, cholesterol, diethanolamine, ethylene
glycol palmitostearate, glycerin monostearate, glyceryl monooleate,
hydroxpropyl cellulose, hypromellose, lanolin, hydrous, lanolin
alcohols, lecithin, medium-chain triglycerides, methylcellulose,
mineral oil and lanolin alcohols, monobasic sodium phosphate,
monoethanolamine, nonionic emulsifying wax, oleic acid, poloxamer,
poloxamers, polyoxyethylene alkyl ethers, polyoxyethylene castor
oil derivatives, polyoxyethylene sorbitan fatty acid esters,
polyoxyethylene stearates, propylene glycol alginate,
self-emulsifying glyceryl monostearate, sodium citrate dehydrate,
sodium lauryl sulfate, sorbitan esters, stearic acid, sunflower
oil, tragacanth, triethanolamine, xanthan gum and combinations
thereof. In one embodiment, the emulsifier is glycerol
stearate.
[0236] Suitable classes of penetration enhancers are known in the
art and include, but are not limited to, fatty alcohols, fatty acid
esters, fatty acids, fatty alcohol ethers, amino acids,
phospholipids, lecithins, cholate salts, enzymes, amines and
amides, complexing agents (liposomes, cyclodextrins, modified
celluloses, and diimides), macrocyclics, such as macrocylic
lactones, ketones, and anhydrides and cyclic ureas, surfactants,
N-methyl pyrrolidones and derivatives thereof, DMSO and related
compounds, ionic compounds, azone and related compounds, and
solvents, such as alcohols, ketones, amides, polyols (e.g.,
glycols). Examples of these classes are known in the art.
Dosing
[0237] The present invention provides methods comprising
administering conjugates or particles containing the conjugate as
described herein to a subject in need thereof. Conjugates or
particles containing the conjugates as described herein may be
administered to a subject using any amount and any route of
administration effective for preventing or treating or imaging a
disease, disorder, and/or condition (e.g., a disease, disorder,
and/or condition relating to working memory deficits). The exact
amount required will vary from subject to subject, depending on the
species, age, and general condition of the subject, the severity of
the disease, the particular composition, its mode of
administration, its mode of activity, and the like.
[0238] Compositions in accordance with the invention are typically
formulated in dosage unit form for ease of administration and
uniformity of dosage. It will be understood, however, that the
total daily usage of the compositions of the present invention may
be decided by the attending physician within the scope of sound
medical judgment. The specific therapeutically effective,
prophylactically effective, or appropriate imaging dose level for
any particular patient will depend upon a variety of factors
including the disorder being treated and the severity of the
disorder; the activity of the specific compound employed; the
specific composition employed; the age, body weight, general
health, sex and diet of the patient; the time of administration,
route of administration, and rate of excretion of the specific
compound employed; the duration of the treatment; drugs used in
combination or coincidental with the specific compound employed;
and like factors well known in the medical arts.
[0239] In some embodiments, compositions in accordance with the
present invention may be administered at dosage levels sufficient
to deliver from about 0.0001 mg/kg to about 100 mg/kg, from about
0.001 mg/kg to about 0.05 mg/kg, from about 0.005 mg/kg to about
0.05 mg/kg, from about 0.001 mg/kg to about 0.005 mg/kg, from about
0.05 mg/kg to about 0.5 mg/kg, from about 0.01 mg/kg to about 50
mg/kg, from about 0.1 mg/kg to about 40 mg/kg, from about 0.5 mg/kg
to about 30 mg/kg, from about 0.01 mg/kg to about 10 mg/kg, from
about 0.1 mg/kg to about 10 mg/kg, or from about 1 mg/kg to about
25 mg/kg, of subject body weight per day, one or more times a day,
to obtain the desired therapeutic, diagnostic, prophylactic, or
imaging effect. The desired dosage may be delivered three times a
day, two times a day, once a day, every other day, every third day,
every week, every two weeks, every three weeks, or every four
weeks. In some embodiments, the desired dosage may be delivered
using multiple administrations (e.g., two, three, four, five, six,
seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, or
more administrations). When multiple administrations are employed,
split dosing regimens such as those described herein may be
used.
[0240] The concentration of the conjugates or particles of the
present invention may be between about 0.01 mg/mL to about 50
mg/mL, about 0.1 mg/mL to about 25 mg/mL, about 0.5 mg/mL to about
10 mg/mL, or about 1 mg/mL to about 5 mg/mL in the pharmaceutical
composition.
[0241] As used herein, a "split dose" is the division of single
unit dose or total daily dose into two or more doses, e.g, two or
more administrations of the single unit dose. As used herein, a
"single unit dose" is a dose of any therapeutic administered in one
dose/at one time/single route/single point of contact, i.e., single
administration event. As used herein, a "total daily dose" is an
amount given or prescribed in 24 hr period. It may be administered
as a single unit dose. In one embodiment, the monomaleimide
compounds of the present invention are administered to a subject in
split doses. The monomaleimide compounds may be formulated in
buffer only or in a formulation described herein.
Dosage Forms
[0242] A pharmaceutical composition described herein can be
formulated into a dosage form described herein, such as a topical,
intranasal, intratracheal, or injectable (e.g., intravenous,
intraocular, intravitreal, intramuscular, intracardiac,
intraperitoneal, subcutaneous).
Liquid Dosage Forms
[0243] Liquid dosage forms for parenteral administration include,
but are not limited to, pharmaceutically acceptable emulsions,
microemulsions, solutions, suspensions, syrups, and/or elixirs. In
addition to active ingredients, liquid dosage forms may comprise
inert diluents commonly used in the art including, but not limited
to, water or other solvents, solubilizing agents and emulsifiers
such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl
acetate, benzyl alcohol, benzyl benzoate, propylene glycol,
1,3-butylene glycol, dimethylformamide, oils (in particular,
cottonseed, groundnut, corn, germ, olive, castor, and sesame oils),
glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and
fatty acid esters of sorbitan, and mixtures thereof. In certain
embodiments for parenteral administration, compositions may be
mixed with solubilizing agents such as CREMOPHOR.RTM., alcohols,
oils, modified oils, glycols, polysorbates, cyclodextrins,
polymers, and/or combinations thereof.
Injectable
[0244] Injectable preparations, for example, sterile injectable
aqueous or oleaginous suspensions may be formulated according to
the known art and may include suitable dispersing agents, wetting
agents, and/or suspending agents. Sterile injectable preparations
may be sterile injectable solutions, suspensions, and/or emulsions
in nontoxic parenterally acceptable diluents and/or solvents, for
example, a solution in 1,3-butanediol. Among the acceptable
vehicles and solvents that may be employed include, but are not
limited to, water, Ringer's solution, U.S.P., and isotonic sodium
chloride solution. Sterile, fixed oils are conventionally employed
as a solvent or suspending medium. For this purpose any bland fixed
oil can be employed including synthetic mono- or diglycerides.
Fatty acids such as oleic acid can be used in the preparation of
injectables.
[0245] Injectable formulations can be sterilized, for example, by
filtration through a bacterial-retaining filter, and/or by
incorporating sterilizing agents in the form of sterile solid
compositions which can be dissolved or dispersed in sterile water
or other sterile injectable medium prior to use.
[0246] In order to prolong the effect of an active ingredient, it
may be desirable to slow the absorption of the active ingredient
from subcutaneous or intramuscular injection. This may be
accomplished by the use of a liquid suspension of crystalline or
amorphous material with poor water solubility. The rate of
absorption of the monomaleimide compounds then depends upon its
rate of dissolution which, in turn, may depend upon crystal size
and crystalline form. Alternatively, delayed absorption of a
parenterally administered monomaleimide compound may be
accomplished by dissolving or suspending the monomalimide in an oil
vehicle. Injectable depot forms are made by forming microencapsule
matrices of the monomaleimide compounds in biodegradable polymers
such as polylactide-polyglycolide. Depending upon the ratio of
monomaleimide compounds to polymer and the nature of the particular
polymer employed, the rate of monomaleimide compound release can be
controlled. Examples of other biodegradable polymers include, but
are not limited to, poly(orthoesters) and poly(anhydrides). Depot
injectable formulations may be prepared by entrapping the
monomaleimide compounds in liposomes or microemulsions which are
compatible with body tissues.
Pulmonary
[0247] Formulations described herein as being useful for pulmonary
delivery may also be used for intranasal delivery of a
pharmaceutical composition. Another formulation suitable for
intranasal administration may be a coarse powder comprising the
active ingredient and having an average particle from about 0.2
.mu.m to 500 .mu.m. Such a formulation may be administered in the
manner in which snuff is taken, i.e. by rapid inhalation through
the nasal passage from a container of the powder held close to the
nose.
[0248] Formulations suitable for nasal administration may, for
example, comprise from about as little as 0.1% (w/w) and as much as
100% (w/w) of active ingredient, and may comprise one or more of
the additional ingredients described herein. A pharmaceutical
composition may be prepared, packaged, and/or sold in a formulation
suitable for buccal administration. Such formulations may, for
example, be in the form of tablets and/or lozenges made using
conventional methods, and may, for example, contain about 0.1% to
20% (w/w) active ingredient, where the balance may comprise an
orally dissolvable and/or degradable composition and, optionally,
one or more of the additional ingredients described herein.
Alternately, formulations suitable for buccal administration may
comprise a powder and/or an aerosolized and/or atomized solution
and/or suspension comprising active ingredient. Such powdered,
aerosolized, and/or aerosolized formulations, when dispersed, may
have an average particle and/or droplet size in the range from
about 0.1 nm to about 200 nm, and may further comprise one or more
of any additional ingredients described herein.
[0249] General considerations in the formulation and/or manufacture
of pharmaceutical agents may be found, for example, in Remington:
The Science and Practice of Pharmacy 21st ed., Lippincott Williams
& Wilkins, 2005 (incorporated herein by reference in its
entirety).
Coatings or Shells
[0250] Solid dosage forms of tablets, dragees, capsules, pills, and
granules can be prepared with coatings and shells such as enteric
coatings and other coatings well known in the pharmaceutical
formulating art. They may optionally comprise opacifying agents and
can be of a composition that they release the active ingredient(s)
only, or preferentially, in a certain part of the intestinal tract,
optionally, in a delayed manner. Examples of embedding compositions
which can be used include polymeric substances and waxes. Solid
compositions of a similar type may be employed as fillers in soft
and hard-filled gelatin capsules using such excipients as lactose
or milk sugar as well as high molecular weight polyethylene glycols
and the like.
IV. Methods of Making Particles
[0251] In various embodiments, a method of making the particles
includes providing a conjugate; providing a base component such as
PLA-PEG or PLGA-PEG for forming a particle; combining the conjugate
and the base component in an organic solution to form a first
organic phase; and combining the first organic phase with a first
aqueous solution to form a second phase; emulsifying the second
phase to form an emulsion phase; and recovering particles. In
various embodiments, the emulsion phase is further homogenized.
[0252] In some embodiments, the first phase includes about 5 to
about 50% weight, e.g. about 1 to about 40% solids, or about 5 to
about 30% solids, e.g. about 5%, 10%, 15%, and 20%, of the
conjugate and the base component. In certain embodiments, the first
phase includes about 5% weight of the conjugate and the base
component. In various embodiments, the organic phase comprises
acetonitrile, tetrahydrofuran, ethyl acetate, isopropyl alcohol,
isopropyl acetate, dimethylformamide, methylene chloride,
dichloromethane, chloroform, acetone, benzyl alcohol, TWEEN.RTM.
80, SPAN.RTM. 80, or a combination thereof. In some embodiments,
the organic phase includes benzyl alcohol, ethyl acetate, or a
combination thereof.
[0253] In various embodiments, the aqueous solution includes water,
sodium cholate, ethyl acetate, or benzyl alcohol. In various
embodiments, a surfactant is added into the first phase, the second
phase, or both. A surfactant, in some instances, can act as an
emulsifier or a stabilizer for a composition disclosed herein. A
suitable surfactant can be a cationic surfactant, an anionic
surfactant, or a nonionic surfactant. In some embodiments, a
surfactant suitable for making a composition described herein
includes sorbitan fatty acid esters, polyoxyethylene sorbitan fatty
acid esters and polyoxyethylene stearates. Examples of such fatty
acid ester nonionic surfactants are the TWEEN.RTM. 80, SPAN.RTM.
80, and MYJ.RTM. surfactants from ICI. SPAN.RTM. surfactants
include C.sub.12-C.sub.18 sorbitan monoesters. TWEEN.RTM.
surfactants include poly(ethylene oxide) C.sub.12-C.sub.18 sorbitan
monoesters. MYJ.RTM. surfactants include poly(ethylene oxide)
stearates. In certain embodiments, the aqueous solution also
comprises a surfactant (e.g., an emulsifier), including a
polysorbate. For example, the aqueous solution can include
polysorbate 80. In some embodiments, a suitable surfactant includes
a lipid-based surfactant. For example, the composition can include
1,2-dihexanoyl-sn-glycero-3-phosphocholine,
1,2-diheptanoyl-sn-glycero-3-phosphocholine, PEGlyated
1,2-distearoyl-sn-glycero-3-phosphoethanolamine (including
PEG5000-DSPE), PEGlyated
1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (including
1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene
glycol)-5000] (ammonium salt)).
[0254] Emulsifying the second phase to form an emulsion phase may
be performed in one or two emulsification steps. For example, a
primary emulsion may be prepared, and then emulsified to form a
fine emulsion. The primary emulsion can be formed, for example,
using simple mixing, a high pressure homogenizer, probe sonicator,
stir bar, or a rotor stator homogenizer. The primary emulsion may
be formed into a fine emulsion through the use of e.g. a probe
sonicator or a high pressure homogenizer, e.g. by pass(es) through
a homogenizer. For example, when a high pressure homogenizer is
used, the pressure used may be about 4000 to about 8000 psi, about
4000 to about 5000 psi, or 4000 or 5000 psi.
[0255] Either solvent evaporation or dilution may be needed to
complete the extraction of the solvent and solidify the particles.
For better control over the kinetics of extraction and a more
scalable process, a solvent dilution via aqueous quench may be
used. For example, the emulsion can be diluted into cold water to a
concentration sufficient to dissolve all of the organic solvent to
form a quenched phase. Quenching may be performed at least
partially at a temperature of about 5.degree. C. or less. For
example, water used in the quenching may be at a temperature that
is less that room temperature (e.g. about 0 to about 10.degree. C.,
or about 0 to about 5.degree. C.).
[0256] In various embodiments, the particles are recovered by
filtration. For example, ultrafiltration membranes can be used.
Exemplary filtration may be performed using a tangential flow
filtration system. For example, by using a membrane with a pore
size suitable to retain particles while allowing solutes, micelles,
and organic solvent to pass, particles can be selectively
separated. Exemplary membranes with molecular weight cut-offs of
about 300-500 kDa (-5-25 nm) may be used.
[0257] In various embodiments, the particles are freeze-dried or
lyophilized, in some instances, to extend their shelf life. In some
embodiments, the composition also includes a lyoprotectant. In
certain embodiments, a lyoprotectant is selected from a sugar, a
polyalcohol, or a derivative thereof. In some embodiments, a
lyoprotectant is selected from a monosaccharide, a disaccharide, or
a mixture thereof. For example, a lyoprotectant can be sucrose,
lactulose, trehalose, lactose, glucose, maltose, mannitol,
cellobiose, or a mixture thereof.
[0258] Methods of making particles containing one or more
conjugates are provided. The particles can be polymeric particles,
lipid particles, or combinations thereof. The various methods
described herein can be adjusted to control the size and
composition of the particles, e.g. some methods are best suited for
preparing microparticles while others are better suited for
preparing particles. The selection of a method for preparing
particles having the descried characteristics can be performed by
the skilled artisan without undue experimentation.
i. Polymeric Particles
[0259] Methods of making polymeric particles are known in the art.
Polymeric particles can be prepared using any suitable method known
in the art. Common microencapsulation techniques include, but are
not limited to, spray drying, interfacial polymerization, hot melt
encapsulation, phase separation encapsulation (spontaneous emulsion
microencapsulation, solvent evaporation microencapsulation, and
solvent removal microencapsulation), coacervation, low temperature
microsphere formation, and phase inversion nanoencapsulation (PIN).
A brief summary of these methods is presented below.
1. Spray Drying
[0260] Methods for forming polymeric particles using spray drying
techniques are described in U.S. Pat. No. 6,620,617. In this
method, the polymer is dissolved in an organic solvent such as
methylene chloride or in water. A known amount of one or more
conjugates or additional active agents to be incorporated in the
particles is suspended (in the case of an insoluble active agent)
or co-dissolved (in the case of a soluble active agent) in the
polymer solution. The solution or dispersion is pumped through a
micronizing nozzle driven by a flow of compressed gas, and the
resulting aerosol is suspended in a heated cyclone of air, allowing
the solvent to evaporate from the microdroplets, forming particles.
Microspheres/nanospheres ranging between 0.1 10 microns can be
obtained using this method.
2. Interfacial Polymerization
[0261] Interfacial polymerization can also be used to encapsulate
one or more conjugates and/or active agents. Using this method, a
monomer and the conjugates or active agent(s) are dissolved in a
solvent. A second monomer is dissolved in a second solvent
(typically aqueous) which is immiscible with the first. An emulsion
is formed by suspending the first solution through stirring in the
second solution. Once the emulsion is stabilized, an initiator is
added to the aqueous phase causing interfacial polymerization at
the interface of each droplet of emulsion.
3. Hot Melt Microencapsulation
[0262] Microspheres can be formed from polymers such as polyesters
and polyanhydrides using hot melt microencapsulation methods as
described in Mathiowitz et al., Reactive Polymers, 6:275 (1987). In
some embodiments employing this method, polymers with molecular
weights between 3,000-75,000 daltons are used. In this method, the
polymer first is melted and then mixed with the solid particles of
one or more active agents to be incorporated that have been sieved
to less than 50 microns. The mixture is suspended in a non-miscible
solvent (like silicon oil), and, with continuous stirring, heated
to 5.degree. C. above the melting point of the polymer. Once the
emulsion is stabilized, it is cooled until the polymer particles
solidify. The resulting microspheres are washed by decanting with
petroleum ether to produce a free flowing powder.
4. Phase Separation Microencapsulation
[0263] In phase separation microencapsulation techniques, a polymer
solution is stirred, optionally in the presence of one or more
active agents to be encapsulated. While continuing to uniformly
suspend the material through stirring, a nonsolvent for the polymer
is slowly added to the solution to decrease the polymer's
solubility. Depending on the solubility of the polymer in the
solvent and nonsolvent, the polymer either precipitates or phase
separates into a polymer rich and a polymer poor phase. Under
proper conditions, the polymer in the polymer rich phase will
migrate to the interface with the continuous phase, encapsulating
the active agent(s) in a droplet with an outer polymer shell.
a. Spontaneous Emulsion Microencapsulation
[0264] Spontaneous emulsification involves solidifying emulsified
liquid polymer droplets formed above by changing temperature,
evaporating solvent, or adding chemical cross-linking agents. The
physical and chemical properties of the encapsulant, as well as the
properties of the one or more active agents optionally incorporated
into the nascent particles, dictates suitable methods of
encapsulation. Factors such as hydrophobicity, molecular weight,
chemical stability, and thermal stability affect encapsulation.
b. Solvent Evaporation Microencapsulation
[0265] Methods for forming microspheres using solvent evaporation
techniques are described in Mathiowitz et al., J. Scanning
Microscopy, 4:329 (1990); Beck et al., Fertil. Steril., 31:545
(1979); Beck et al., Am. J. Obstet. Gynecol. 135(3) (1979); Benita
et al., J. Pharm. Sci., 73:1721 (1984); and U.S. Pat. No.
3,960,757. The polymer is dissolved in a volatile organic solvent,
such as methylene chloride. One or more active agents to be
incorporated are optionally added to the solution, and the mixture
is suspended in an aqueous solution that contains a surface active
agent such as poly(vinyl alcohol). The resulting emulsion is
stirred until most of the organic solvent evaporated, leaving solid
microparticles/nanoparticles. This method is useful for relatively
stable polymers like polyesters and polystyrene.
c. Solvent Removal Microencapsulation
[0266] The solvent removal microencapsulation technique is
primarily designed for polyanhydrides and is described, for
example, in WO 93/21906. In this method, the substance to be
incorporated is dispersed or dissolved in a solution of the
selected polymer in a volatile organic solvent, such as methylene
chloride. This mixture is suspended by stirring in an organic oil,
such as silicon oil, to form an emulsion. Microspheres that range
between 1-300 microns can be obtained by this procedure. Substances
which can be incorporated in the microspheres include
pharmaceuticals, pesticides, nutrients, imaging agents, and metal
compounds.
5. Coacervation
[0267] Encapsulation procedures for various substances using
coacervation techniques are known in the art, for example, in
GB-B-929 406; GB-B-929 40 1; and U.S. Pat. Nos. 3,266,987,
4,794,000, and 4,460,563. Coacervation involves the separation of a
macromolecular solution into two immiscible liquid phases. One
phase is a dense coacervate phase, which contains a high
concentration of the polymer encapsulant (and optionally one or
more active agents), while the second phase contains a low
concentration of the polymer. Within the dense coacervate phase,
the polymer encapsulant forms nanoscale or microscale droplets.
Coacervation may be induced by a temperature change, addition of a
non-solvent or addition of a micro-salt (simple coacervation), or
by the addition of another polymer thereby forming an interpolymer
complex (complex coacervation).
6. Low Temperature Casting of Microspheres
[0268] Methods for very low temperature casting of controlled
release particles are described in U.S. Pat. No. 5,019,400. In this
method, a polymer is dissolved in a solvent optionally with one or
more dissolved or dispersed active agents. The mixture is then
atomized into a vessel containing a liquid non solvent at a
temperature below the freezing point of the polymer substance
solution which freezes the polymer droplets. As the droplets and
non solvent for the polymer are warmed, the solvent in the droplets
thaws and is extracted into the non solvent, resulting in the
hardening of the microspheres.
7. Phase Inversion Nanoencapsulation (PIN)
[0269] Particles can also be formed using the phase inversion
nanoencapsulation (PIN) method, wherein a polymer is dissolved in a
"good" solvent, fine particles of a substance to be incorporated,
such as a drug, are mixed or dissolved in the polymer solution, and
the mixture is poured into a strong non solvent for the polymer, to
spontaneously produce, under favorable conditions, polymeric
microspheres, wherein the polymer is either coated with the
particles or the particles are dispersed in the polymer. See, e.g.,
U.S. Pat. No. 6,143,211. The method can be used to produce
monodisperse populations of nanoparticles and microparticles in a
wide range of sizes, including, for example, about 100 nanometers
to about 10 microns.
[0270] Advantageously, an emulsion need not be formed prior to
precipitation. The process can be used to form microspheres from
thermoplastic polymers.
8. Emulsion Methods
[0271] In some embodiments, a particle is prepared using an
emulsion solvent evaporation method. For example, a polymeric
material is dissolved in a water immiscible organic solvent and
mixed with a drug solution or a combination of drug solutions. In
some embodiments a solution of a therapeutic, prophylactic, or
diagnostic agent to be encapsulated is mixed with the polymer
solution. The polymer can be, but is not limited to, one or more of
the following: PLA, PGA, PCL, their copolymers, polyacrylates, the
aforementioned PEGylated polymers. The drug molecules can include
one or more conjugates as described above and one or more
additional active agents. The water immiscible organic solvent, can
be, but is not limited to, one or more of the following:
chloroform, dichloromethane, and acyl acetate. The drug can be
dissolved in, but is not limited to, one or more of the following:
acetone, ethanol, methanol, isopropyl alcohol, acetonitrile and
Dimethyl sulfoxide (DMSO).
[0272] An aqueous solution is added into the resulting polymer
solution to yield emulsion solution by emulsification. The
emulsification technique can be, but not limited to, probe
sonication or homogenization through a homogenizer.
9. Nanoprecipitation
[0273] In another embodiment, a conjugate containing nanoparticle
is prepared using nanoprecipitation methods or microfluidic
devices. The conjugate containing polymeric material is mixed with
a drug or drug combinations in a water miscible organic solvent,
optionally containing additional polymers. The additional polymer
can be, but is not limited to, one or more of the following: PLA,
PGA, PCL, their copolymers, polyacrylates, the aforementioned
PEGylated polymers. The water miscible organic solvent, can be, but
is not limited to, one or more of the following: acetone, ethanol,
methanol, isopropyl alcohol, acetonitrile and dimethyl sulfoxide
(DMSO). The resulting mixture solution is then added to a polymer
non-solvent, such as an aqueous solution, to yield nanoparticle
solution.
10. Microfluidics
[0274] Methods of making particles using microfluidics are known in
the art. Suitable methods include those described in U.S. Patent
Application Publication No. 2010/0022680 A1. In general, the
microfluidic device comprises at least two channels that converge
into a mixing apparatus. The channels are typically formed by
lithography, etching, embossing, or molding of a polymeric surface.
A source of fluid is attached to each channel, and the application
of pressure to the source causes the flow of the fluid in the
channel. The pressure may be applied by a syringe, a pump, and/or
gravity. The inlet streams of solutions with polymer, targeting
moieties, lipids, drug, payload, etc. converge and mix, and the
resulting mixture is combined with a polymer non-solvent solution
to form the particles having the desired size and density of
moieties on the surface. By varying the pressure and flow rate in
the inlet channels and the nature and composition of the fluid
sources particles can be produced having reproducible size and
structure.
ii. Lipid Particles
[0275] Methods of making lipid particles are known in the art.
Lipid particles can be lipid micelles, liposomes, or solid lipid
particles prepared using any suitable method known in the art.
Common techniques for created lipid particles encapsulating an
active agent include, but are not limited to high pressure
homogenization techniques, supercritical fluid methods, emulsion
methods, solvent diffusion methods, and spray drying. A brief
summary of these methods is presented below.
1. High Pressure Homogenization (HPH) Methods
[0276] High pressure homogenization is a reliable and powerful
technique, which is used for the production of smaller lipid
particles with narrow size distributions, including lipid micelles,
liposomes, and solid lipid particles. High pressure homogenizers
push a liquid with high pressure (100-2000 bar) through a narrow
gap (in the range of a few microns). The fluid can contain lipids
that are liquid at room temperature or a melt of lipids that are
solid at room temperature. The fluid accelerates on a very short
distance to very high velocity (over 1000 Km/h). This creates high
shear stress and cavitation forces that disrupt the particles,
generally down to the submicron range. Generally 5-10% lipid
content is used but up to 40% lipid content has also been
investigated.
[0277] Two approaches of HPH are hot homogenization and cold
homogenization, work on the same concept of mixing the drug in bulk
of lipid solution or melt.
a. Hot Homogenization:
[0278] Hot homogenization is carried out at temperatures above the
melting point of the lipid and can therefore be regarded as the
homogenization of an emulsion. A pre-emulsion of the drug loaded
lipid melt and the aqueous emulsifier phase is obtained by a
high-shear mixing. HPH of the pre-emulsion is carried out at
temperatures above the melting point of the lipid. A number of
parameters, including the temperature, pressure, and number of
cycles, can be adjusted to produce lipid particles with the desired
size. In general, higher temperatures result in lower particle
sizes due to the decreased viscosity of the inner phase. However,
high temperatures increase the degradation rate of the drug and the
carrier. Increasing the homogenization pressure or the number of
cycles often results in an increase of the particle size due to
high kinetic energy of the particles.
b. Cold Homogenization
[0279] Cold homogenization has been developed as an alternative to
hot homogenization. Cold homogenization does not suffer from
problems such as temperature-induced drug degradation or drug
distribution into the aqueous phase during homogenization. The cold
homogenization is particularly useful for solid lipid particles,
but can be applied with slight modifications to produce liposomes
and lipid micelles. In this technique the drug containing lipid
melt is cooled, the solid lipid ground to lipid microparticles and
these lipid microparticles are dispersed in a cold surfactant
solution yielding a pre-suspension. The pre-suspension is
homogenized at or below room temperature, where the gravitation
force is strong enough to break the lipid microparticles directly
to solid lipid nanoparticles.
2. Ultrasonication/High Speed Homogenization Methods
[0280] Lipid particles, including lipid micelles, liposomes, and
solid lipid particles, can be prepared by ultrasonication/high
speed homogenization. The combination of both ultrasonication and
high speed homogenization is particularly useful for the production
of smaller lipid particles. Liposomes are formed in the size range
from 10 nm to 200 nm, for example, 50 nm to 100 nm, by this
process.
3. Solvent Evaporation Methods
[0281] Lipid particles can be prepared by solvent evaporation
approaches. The lipophilic material is dissolved in a
water-immiscible organic solvent (e.g. cyclohexane) that is
emulsified in an aqueous phase. Upon evaporation of the solvent,
particles dispersion is formed by precipitation of the lipid in the
aqueous medium. Parameters such as temperature, pressure, choices
of solvents can be used to control particle size and distribution.
Solvent evaporation rate can be adjusted through increased/reduced
pressure or increased/reduced temperature.
4. Solvent Emulsification-Diffusion Methods
[0282] Lipid particles can be prepared by solvent
emulsification-diffusion methods. The lipid is first dissolved in
an organic phase, such as ethanol and acetone. An acidic aqueous
phase is used to adjust the zeta potential to induce lipid
coacervation. The continuous flow mode allows the continuous
diffusion of water and alcohol, reducing lipid solubility, which
causes thermodynamic instability and generates liposomes
5. Supercritical Fluid Methods
[0283] Lipid particles, including liposomes and solid lipid
particles, can be prepared from supercritical fluid methods.
Supercritical fluid approaches have the advantage of replacing or
reducing the amount of the organic solvents used in other
preparation methods. The lipids, active agents to be encapsulated,
and excipients can be solvated at high pressure in a supercritical
solvent. The supercritical solvent is most commonly CO.sub.2,
although other supercritical solvents are known in the art. To
increase solubility of the lipid, a small amount of co-solvent can
be used. Ethanol is a common co-solvent, although other small
organic solvents that are generally regarded as safe for
formulations can be used. The lipid particles, lipid micelles,
liposomes, or solid lipid particles can be obtained by expansion of
the supercritical solution or by injection into a non-solvent
aqueous phase. The particle formation and size distribution can be
controlled by adjusting the supercritical solvent, co-solvent,
non-solvent, temperatures, pressures, etc.
6. Microemulsion Based Methods
[0284] Microemulsion based methods for making lipid particles are
known in the art. These methods are based upon the dilution of a
multiphase, usually two-phase, system. Emulsion methods for the
production of lipid particles generally involve the formation of a
water-in-oil emulsion through the addition of a small amount of
aqueous media to a larger volume of immiscible organic solution
containing the lipid. The mixture is agitated to disperse the
aqueous media as tiny droplets throughout the organic solvent and
the lipid aligns itself into a monolayer at the boundary between
the organic and aqueous phases. The size of the droplets is
controlled by pressure, temperature, the agitation applied and the
amount of lipid present.
[0285] The water-in-oil emulsion can be transformed into a
liposomal suspension through the formation of a double emulsion. In
a double emulsion, the organic solution containing the water
droplets is added to a large volume of aqueous media and agitated,
producing a water-in-oil-in-water emulsion. The size and type of
lipid particle formed can be controlled by the choice of and amount
of lipid, temperature, pressure, co-surfactants, solvents, etc.
7. Spray Drying Methods
[0286] Spray drying methods similar to those described above for
making polymeric particle can be employed to create solid lipid
particles. Typically, this method is used with lipids with a
melting point above 70.degree. C.
[0287] In some embodiments, conjugates of the present invention may
be encapsulated in polymeric particles using a single oil in water
emulsion method. As a non-limiting example, the conjugate and a
suitable polymer or block copolymer or a mixture of polymers/block
copolymers, are dissolved in organic solvents such as, but not
limited to, dichloromethane (DCM), ethyl acetate (EtAc) or
choloform to form the oil phase. Co-solvents such as, but not
limited to, dimethyl formamide (DMF), acetonitrile (CAN) or benzyl
alcohol (BA) may be used to control the size of the particles
and/or to solubilize the conjugate. Polymers used in the
formulation may include, but not limited to, PLA97-b-PEGS,
PLA35-b-PEGS and PLA16-b-PEGS copolymers.
[0288] In some embodiments, particle formulations may be prepared
by varying the lipophilicity of conjugates of the present
invention. The lipophilicity may be varied by using hydrophobic
ion-pairs or hydrophobic ion-paring (HIP) of the conjugates with
different counterions. HIP alters the solubility of the conjugates
of the present invention. The aqueous solubility may drop and the
solubility in organic phases may increase.
[0289] Any suitable agent may be used to provide counterions to
form HIP complex with the conjugate of the present invention. In
some embodiments, the HIP complex may be formed prior to
formulation of the particles.
V. Methods of Using the Conjugates and Particles
[0290] The conjugates or particles as described herein can be
administered to treat any hyperproliferative disease, metabolic
disease, infectious disease, or cancer, as appropriate. The
formulations can be used for immunization. Formulations may be
administered by injection, orally, or topically, typically to a
mucosal surface (lung, nasal, oral, buccal, sublingual, vaginally,
rectally) or to the eye (intraocularly or transocularly).
[0291] In various embodiments, methods for treating a subject
having a cancer are provided, wherein the method comprises
administering a therapeutically-effective amount of the conjugates
or particles, as described herein, to a subject having a cancer,
suspected of having cancer, or having a predisposition to a cancer.
According to the present invention, cancer embraces any disease or
malady characterized by uncontrolled cell proliferation, e.g.,
hyperproliferation. Cancers may be characterized by tumors, e.g.,
solid tumors or any neoplasm.
[0292] In some embodiments, the cancer is a solid tumor. Large drug
molecules have limited penetration in solid tumors. The penetration
of large drug molecules is slow. On the other hand, small molecules
such as conjugates of the present invention may penetrate solid
tumors rapidly and more deeply. Regarding penetration depth of the
drugs, larger molecules penetrate less, despite having more durable
pharmacokinectics. Small molecules such as conjugates of the
present invention penetrate deeper. Dreher et al. (Dreher et al.,
JNCI, vol. 98(5):335 (2006), the contents of which are incorporated
herein by reference in their entirety) studied penetration of
dextrans with different sizes into a tumor xenograft. As summarized
in FIG. 6 (see FIG. 1 of the present application) and Table 1 of
Dreher, Dextrans with a molecular weight of 3.3 kDa or 10 kDa
showed rapid deep penetration into the tumor tissue (>35 um from
the vascular surface of the tumor). However, 40 kDa, 70 kDa or 2
mDa sized dextrans penetrated much less than the 3.3 kDa or 10 kDa
dextran. The 70 kDa dextran reached only about 15 um from the
vascular surface of the tumor. Conjugates of the present invention
have a molecule weight comparable to the 3.3 kDa and 10 kDa
dextrans, while antibody drug conjugates have a molecule weight at
least as big as the 70 kDa dextran. Therefore, conjugates of the
present invention may penetrate deep and rapidly into the
core/center of the solid tumor.
[0293] In one embodiment, conjugates of the present invention reach
at least about 25 .mu.m, about 30 .mu.m, about 35 .mu.m, about 40
.mu.m, about 45 .mu.m, about 50 .mu.m, about 75 .mu.m, about 100
.mu.m, about 150 .mu.m, about 200 .mu.m, about 250 .mu.m, about 300
.mu.m, about 400 .mu.m, about 500 .mu.m, about 600 .mu.m, about 700
.mu.m, about 800 .mu.m, about 900 .mu.m, about 1000 .mu.m, about
1100 .mu.m, about 1200 .mu.m, about 1300 .mu.m, about 1400 .mu.m or
about 1500 .mu.m into the solid tumor from the vascular surface of
the tumor. Zero distance is defined as the vascular surface of the
tumor, and every distance greater than zero is defined as the
distance measured in three dimensions to the nearest vascular
surface.
[0294] In another embodiment, conjugates of the present invention
penetrate to the core of the tumor. "Core" of the tumor, as used
herein, refers to the central area of the tumor. The distance from
any part of the core area of the tumor to the vascular surface of
the tumor is between about 30% to about 50% of the length or width
of the tumor. The distance from any part of the core area of the
tumor to the center point of the tumor is less than about 20% of
the length or width of the tumor. The core area of the tumor is
roughly the center 1/3 of the tumor.
[0295] In another embodiment, conjugates of the present invention
conjugates of the present invention penetrate to the middle of the
solid tumor. "Middle" of the tumor, as sued herein, refers to the
middle area of the tumor. The distance from any part of the middle
area of the tumor to the vascular surface of the tumor is between
about 15% and about 30% of the length or the width of the tumor.
The distance from any part of the middle area of the tumor to the
center point of the tumor is between about 20% to about 35% of the
length or width of the tumor. The middle area of the tumor is
roughly between the center 1/3 of the tumor and the outer 1/3 of
the tumor.
[0296] In some embodiments, the subject may be otherwise free of
indications for treatment with the conjugates or particles. In some
embodiments, methods include use of cancer cells, including but not
limited to mammalian cancer cells. In some instances, the mammalian
cancer cells are human cancer cells.
[0297] In some embodiments, the conjugates or particles of the
present teachings have been found to inhibit cancer and/or tumor
growth. They may also reduce, including cell proliferation,
invasiveness, and/or metastasis, thereby rendering them useful for
the treatment of a cancer.
[0298] In some embodiments, the conjugates or particles of the
present teachings may be used to prevent the growth of a tumor or
cancer, and/or to prevent the metastasis of a tumor or cancer. In
some embodiments, compositions of the present teachings may be used
to shrink or destroy a cancer.
[0299] In some embodiments, the conjugates or particles provided
herein are useful for inhibiting proliferation of a cancer cell. In
some embodiments, the conjugates or particles provided herein are
useful for inhibiting cellular proliferation, e.g., inhibiting the
rate of cellular proliferation, preventing cellular proliferation,
and/or inducing cell death. In general, the conjugates or particles
as described herein can inhibit cellular proliferation of a cancer
cell or both inhibiting proliferation and/or inducing cell death of
a cancer cell. In some embodiments, cell proliferation is reduced
by at least about 25%, about 50%, about 75%, or about 90% after
treatment with conjugates or particles of the present invention
compared with cells with no treatment. In some embodiments, cell
cycle arrest marker phospho histone H3 (PH3 or PHH3) is increased
by at least about 50%, about 75%, about 100%, about 200%, about
400% or about 600% after treatment with conjugates or particles of
the present invention compared with cells with no treatment. In
some embodiments, cell apoptosis marker cleaved caspase-3 (CC3) is
increased by at least 50%, about 75%, about 100%, about 200%, about
400% or about 600% after treatment with conjugates or particles of
the present invention compared with cells with no treatment.
[0300] Furthermore, in some embodiments, conjugates or particles of
the present invention are effective for inhibiting tumor growth,
whether measured as a net value of size (weight, surface area or
volume) or as a rate over time, in multiple types of tumors.
[0301] In some embodiments the size of a tumor is reduced by about
60% or more after treatment with conjugates or particles of the
present invention. In some embodiments, the size of a tumor is
reduced by at least about 20%, at least about 30%, at least about
40%, at least about 50%, at least about 60%, at least about 70%, at
least about 80%, at least about 90%, at least about 95%, at least
about 96%, at least about 97%, at least about 98%, at least about
99%, at least about 100%, by a measure of weight, and/or area
and/or volume.
[0302] The cancers treatable by methods of the present teachings
generally occur in mammals. Mammals include, for example, humans,
non-human primates, dogs, cats, rats, mice, rabbits, ferrets,
guinea pigs horses, pigs, sheep, goats, and cattle. In various
embodiments, the cancer is lung cancer, breast cancer, e.g., mutant
BRCA1 and/or mutant BRCA2 breast cancer, non-BRCA-associated breast
cancer, colorectal cancer, ovarian cancer, pancreatic cancer,
colorectal cancer, bladder cancer, prostate cancer, cervical
cancer, renal cancer, leukemia, central nervous system cancers,
myeloma, and melanoma. In some embodiments, the cancer is a
neuroendocrine cancer such as but not limited to small cell lung
cancer (SCLC), adrenal medullary tumors (e.g., pheochromocytoma,
neuroblastoma, ganglioneuroma, or paraganglioma),
gastroenteropancreatic neuroendocrine tumors (e.g., carcinoids,
gastrinoma, glucagonoma, vasoactive intestinal
polypeptide-secreting tumor, pancreatic polypeptide-secreting
tumor, or nonfunctioning gastroenteropancreatic tumors), meduallary
thyroid cancer, Merkel cell tumor of the skin, pituitary adenoma,
and pancreatic cancer. The somatostain receptor SSTR2 is over
expressed on 50-90% of neuroendocrine cancers. In some embodiments,
the neuroendocrine cancer is a primary neuroendocrine cancer. In
some embodiments, the neuroendocrine cancer is a neuroendocrine
metastatsis. Neuroendocrine metastatis may be in liver, lung, bone,
or brain of a subject. In certain embodiments, the cancer is brain
cancer, human lung carcinoma, ovarian cancer, pancreatic cancer or
colorectal cancer.
[0303] In one embodiment, the conjugates or particles as described
herein or formulations containing the conjugates or particles as
described herein are used to treat small cell lung cancer. About
12%-15% of patients having lung cancer have small cell lung cancer.
Survival in metastatic small cell lung caner is poor. Survival rate
is below 5% five years after diagnosis. US incidence of small cell
lung cancer is about 26K-30K. Among these patients, about 40%-80%
are SSTR2 positive.
[0304] In some embodiments, the conjugates or particles as
described herein or formulations containing the conjugates or
particles as described herein are used to treat patients with
tumors that express or over-express the somatostatn receptor. Such
patients can be identified with any method known in the art, such
as but not limited to using a radionuclide imaging agent, a
radiolabeled somatostatin analog imaging agent, SSTR scintigraphy
or SSTR positron emission tomography (PET). In one embodiment,
.sup.111Indium (Indium111)-labeled pentetreotide scintigraphy
(OctreoScan.TM.) is used to identify patients with SSTR-expressing
tumors. In another embodiment, a 68Ga conjugate such as
68Ga-DOTA-TATE, 68Ga-DOTA-TOC, or 68Ga-DOTA-NOC is used in PET
imaging to identify patients with SSTR-expressing tumors. Patients
who show positive scan results detected with Indium111-labeled
pentetreotide scintigraphy are treated with conjugates or particles
of the present invention.
[0305] A feature of conjugates or particles of the present
invention is relatively low toxicity to an organism while
maintaining efficacy at inhibiting, e.g. slowing or stopping tumor
growth. As used herein, "toxicity" refers to the capacity of a
substance or composition to be harmful or poisonous to a cell,
tissue organism or cellular environment. Low toxicity refers to a
reduced capacity of a substance or composition to be harmful or
poisonous to a cell, tissue organism or cellular environment. Such
reduced or low toxicity may be relative to a standard measure,
relative to a treatment or relative to the absence of a treatment.
For example, conjugates or particles of the present invention may
have lower toxicity than the active agent moiety Z administered
alone. For conjugates comprising DM1, their toxicity is lower than
DM1 administered alone.
[0306] Toxicity may further be measured relative to a subject's
weight loss where weight loss over 15%, over 20% or over 30% of the
body weight is indicative of toxicity. Other metrics of toxicity
may also be measured such as patient presentation metrics including
lethargy and general malaiase. Neutropenia, thrombopenia, white
blood cell (WBC) count, complete blood cell (CBC) count may also be
metrics of toxicity. Pharmacologic indicators of toxicity include
elevated aminotransferases (AST/ALT) levels, neurotoxicity, kidney
damage, GI damage and the like. In one embodiment, conjugates or
particles of the present invention do not cause a significant
change of a subject's body weight. The body weight loss of a
subject is less about 30%, about 20%, about 15%, about 10%, or
about 5% after treatment with conjugates or particles of the
present invention. In another embodiment, conjugates or particles
of the present invention do not cause a significant increase of a
subject's AST/ALT levels. The AST or ALT level of a subject is
increased by less than about 30%, about 20%, about 15%, about 10%,
or about 5% after treatment with conjugates or particles of the
present invention. In yet another embodiment, conjugates or
particles of the present invention do not cause a significant
change of a subject's CBC or WBC count after treatment with
conjugates or particles of the present invention. The CBC or WBC
level of a subject is decreased by less than about 30%, about 20%,
about 15%, about 10%, or about 5% after treatment with conjugates
or particles of the present invention.
[0307] In some embodiments, conjugates or particles of the present
invention are combined with at least one additional active agent.
The active agent may be any suitable drug. It may be selected from
any active agent described herein such as a drug for treating
cancer. It may also be a cancer symptom relief drug. Non-limiting
examples of symptom relief drugs include: octreotide or lanreotide;
interferon, cypoheptadine or any other antihistamines. In some
embodiments, conjugates or particles of the present invention do
not have drug-drug interference with the additional active agent.
In one embodiment, conjugates or particles of the present invention
do not inhibit cytochrome P450 (CYP) isozymes. CYP isozymes may
include CYP3A4 Midazolam, CYP3A4 Testosterone, CYP2C9, CYP2D6,
CYP1A2, CYP2C8, CYP2B6, and CYP2C19. The additional active agent
may be administered concomitantly with conjugates or particles of
the present invention.
[0308] In some embodiments, the additional active agent may not
bind to any somatostatin receptor. In one embodiment, the
additional active agent is a cancer symptom relief drug. The
symptom relief drug may reduce diarrhea or the side effects of
chemotherapy or radiation therapy. In one example, conjugates or
particles of the present invention may be combined with a symptom
relief drug for carcinoid syndrome, such as telotristat or
telotristat etiprate (LX1032, Lexicon.RTM.). Telotristat etiprate
is telotristat's crystalline hippurate salt as disclosed in
WO2013059146 to Chen et al., the contents of which are incorporated
herein by reference in their entirety. Telotristat, its salts and
crystalline forms can be obtained by methods known in the art (see
U.S. Pat. No. 7,709,493 to Devasagayaraj et al., the contents of
which are incorporated herein by reference in their entirety). Any
other compound disclosed in U.S. Pat. No. 7,709,493 may be combined
with conjugates or particles of the present invention.
Telotristat:
##STR00203##
[0310] In another example, conjugates or particles of the present
invention may be combined with a moderate dose of chemotherapy
agents such as mitomycin C, vinblastine and cisplatin (see Ellis et
al., Br J Cancer, vol. 71(2): 366-370 (1995), the contents of which
are incorporated herein by reference in their entirety).
[0311] The conjugates or particles as described herein or
formulations containing the conjugates or particles as described
herein can be used for the selective tissue delivery of a
therapeutic, prophylactic, or diagnostic agent to an individual or
patient in need thereof. For example, DM1 conjugates or particles
of the present invention are used to deliver DM1 to selective
tissues. These tissues may be tumor tissues. Dosage regimens may be
adjusted to provide the optimum desired response (e.g., a
therapeutic or prophylactic response). For example, a single bolus
may be administered, several divided doses may be administered over
time or the dose may be proportionally reduced or increased as
indicated by the exigencies of the therapeutic situation. Dosage
unit form as used herein refers to physically discrete units suited
as unitary dosages for the mammalian subjects to be treated; each
unit containing a predetermined quantity of active compound
calculated to produce the desired therapeutic.
[0312] In various embodiments, a conjugate contained within a
particle is released in a controlled manner. The release can be in
vitro or in vivo. For example, particles can be subject to a
release test under certain conditions, including those specified in
the U.S. Pharmacopeia and variations thereof.
[0313] In various embodiments, less than about 90%, less than about
80%, less than about 70%, less than about 60%, less than about 50%,
less than about 40%, less than about 30%, less than about 20% of
the conjugate contained within particles is released in the first
hour after the particles are exposed to the conditions of a release
test. In some embodiments, less that about 90%, less than about
80%, less than about 70%, less than about 60%, or less than about
50% of the conjugate contained within particles is released in the
first hour after the particles are exposed to the conditions of a
release test. In certain embodiments, less than about 50% of the
conjugate contained within particles is released in the first hour
after the particles are exposed to the conditions of a release
test.
[0314] With respect to a conjugate being released in vivo, for
instance, the conjugate contained within a particle administered to
a subject may be protected from a subject's body, and the body may
also be isolated from the conjugate until the conjugate is released
from the particle.
[0315] Thus, in some embodiments, the conjugate may be
substantially contained within the particle until the particle is
delivered into the body of a subject. For example, less than about
90%, less than about 80%, less than about 70%, less than about 60%,
less than about 50%, less than about 40%, less than about 30%, less
than about 20%, less than about 15%, less than about 10%, less than
about 5%, or less than about 1% of the total conjugate is released
from the particle prior to the particle being delivered into the
body, for example, a treatment site, of a subject. In some
embodiments, the conjugate may be released over an extended period
of time or by bursts (e.g., amounts of the conjugate are released
in a short period of time, followed by a periods of time where
substantially no conjugate is released). For example, the conjugate
can be released over 6 hours, 12 hours, 24 hours, or 48 hours. In
certain embodiments, the conjugate is released over one week or one
month.
VI. Kits and Devices
[0316] The invention provides a variety of kits and devices for
conveniently and/or effectively carrying out methods of the present
invention. Typically kits will comprise sufficient amounts and/or
numbers of components to allow a user to perform multiple
treatments of a subject(s) and/or to perform multiple
experiments.
[0317] In one embodiment, the present invention provides kits for
inhibiting tumor cell growth in vitro or in vivo, comprising a
conjugate and/or particle of the present invention or a combination
of conjugates and/or particles of the present invention, optionally
in combination with any other active agents.
[0318] The kit may further comprise packaging and instructions
and/or a delivery agent to form a formulation composition. The
delivery agent may comprise a saline, a buffered solution, or any
delivery agent disclosed herein. The amount of each component may
be varied to enable consistent, reproducible higher concentration
saline or simple buffer formulations. The components may also be
varied in order to increase the stability of the conjugates and/or
particles in the buffer solution over a period of time and/or under
a variety of conditions.
[0319] The present invention provides for devices which may
incorporate conjugates and/or particles of the present invention.
These devices contain in a stable formulation available to be
immediately delivered to a subject in need thereof, such as a human
patient. In some embodiments, the subject has cancer.
[0320] Non-limiting examples of the devices include a pump, a
catheter, a needle, a transdermal patch, a pressurized olfactory
delivery device, iontophoresis devices, multi-layered microfluidic
devices. The devices may be employed to deliver conjugates and/or
particles of the present invention according to single, multi- or
split-dosing regiments. The devices may be employed to deliver
conjugates and/or particles of the present invention across
biological tissue, intradermal, subcutaneously, or
intramuscularly.
VII. Definitions
[0321] The term "compound", as used herein, is meant to include all
stereoisomers, geometric isomers, tautomers, and isotopes of the
structures depicted. In the present application, compound is used
interechangably with conjugate. Therefore, conjugate, as used
herein, is also meant to include all stereoisomers, geometric
isomers, tautomers, and isotopes of the structures depicted.
[0322] The compounds described herein can be asymmetric (e.g.,
having one or more stereocenters). All stereoisomers, such as
enantiomers and diastereomers, are intended unless otherwise
indicated. Compounds of the present disclosure that contain
asymmetrically substituted carbon atoms can be isolated in
optically active or racemic forms. Methods on how to prepare
optically active forms from optically active starting materials are
known in the art, such as by resolution of racemic mixtures or by
stereoselective synthesis. Many geometric isomers of olefins,
C.dbd.N double bonds, and the like can also be present in the
compounds described herein, and all such stable isomers are
contemplated in the present disclosure. Cis and trans geometric
isomers of the compounds of the present disclosure are described
and may be isolated as a mixture of isomers or as separated
isomeric forms.
[0323] Compounds of the present disclosure also include tautomeric
forms. Tautomeric forms result from the swapping of a single bond
with an adjacent double bond and the concomitant migration of a
proton. Tautomeric forms include prototropic tautomers which are
isomeric protonation states having the same empirical formula and
total charge. Examples prototropic tautomers include ketone--enol
pairs, amide--imidic acid pairs, lactam--lactim pairs,
amide--imidic acid pairs, enamine--imine pairs, and annular forms
where a proton can occupy two or more positions of a heterocyclic
system, such as, 1H- and 3H-imidazole, 1H-, 2H- and
4H-1,2,4-triazole, 1H- and 2H-isoindole, and 1H- and 2H-pyrazole.
Tautomeric forms can be in equilibrium or sterically locked into
one form by appropriate substitution.
[0324] Compounds of the present disclosure also include all of the
isotopes of the atoms occurring in the intermediate or final
compounds. "Isotopes" refers to atoms having the same atomic number
but different mass numbers resulting from a different number of
neutrons in the nuclei. For example, isotopes of hydrogen include
tritium and deuterium.
[0325] The compounds and salts of the present disclosure can be
prepared in combination with solvent or water molecules to form
solvates and hydrates by routine methods.
[0326] The terms "subject" or "patient", as used herein, refer to
any organism to which the particles may be administered, e.g., for
experimental, therapeutic, diagnostic, and/or prophylactic
purposes. Typical subjects include animals (e.g., mammals such as
mice, rats, rabbits, guinea pigs, cattle, pigs, sheep, horses,
dogs, cats, hamsters, lamas, non-human primates, and humans).
[0327] The terms "treating" or "preventing", as used herein, can
include preventing a disease, disorder or condition from occurring
in an animal that may be predisposed to the disease, disorder
and/or condition but has not yet been diagnosed as having the
disease, disorder or condition; inhibiting the disease, disorder or
condition, e.g., impeding its progress; and relieving the disease,
disorder, or condition, e.g., causing regression of the disease,
disorder and/or condition. Treating the disease, disorder, or
condition can include ameliorating at least one symptom of the
particular disease, disorder, or condition, even if the underlying
pathophysiology is not affected, such as treating the pain of a
subject by administration of an analgesic agent even though such
agent does not treat the cause of the pain.
[0328] A "target", as used herein, shall mean a site to which
targeted constructs bind. A target may be either in vivo or in
vitro. In certain embodiments, a target may be cancer cells found
in leukemias or tumors (e.g., tumors of the brain, lung (small cell
and non-small cell), ovary, prostate, breast and colon as well as
other carcinomas and sarcomas). In still other embodiments, a
target may refer to a molecular structure to which a targeting
moiety or ligand binds, such as a hapten, epitope, receptor, dsDNA
fragment, carbohydrate or enzyme. A target may be a type of tissue,
e.g., neuronal tissue, intestinal tissue, pancreatic tissue, liver,
kidney, prostate, ovary, lung, bone marrow, or breast tissue.
[0329] The "target cells" that may serve as the target for the
method or conjugates or particles, are generally animal cells,
e.g., mammalian cells. The present method may be used to modify
cellular function of living cells in vitro, i.e., in cell culture,
or in vivo, in which the cells form part of or otherwise exist in
animal tissue. Thus, the target cells may include, for example, the
blood, lymph tissue, cells lining the alimentary canal, such as the
oral and pharyngeal mucosa, cells forming the villi of the small
intestine, cells lining the large intestine, cells lining the
respiratory system (nasal passages/lungs) of an animal (which may
be contacted by inhalation of the subject invention),
dermal/epidermal cells, cells of the vagina and rectum, cells of
internal organs including cells of the placenta and the so-called
blood/brain barrier, etc. In general, a target cell expresses at
least one type of SSTR. In some embodiments, a target cell can be a
cell that expresses an SSTR and is targeted by a conjugate
described herein, and is near a cell that is affected by release of
the active agent of the conjugate. For example, a blood vessel
expressing an SSTR that is in proximity to a tumor may be the
target, while the active agent released at the site will affect the
tumor.
[0330] The term "therapeutic effect" is art-recognized and refers
to a local or systemic effect in animals, particularly mammals, and
more particularly humans caused by a pharmacologically active
substance. The term thus means any substance intended for use in
the diagnosis, cure, mitigation, treatment or prevention of
disease, disorder or condition in the enhancement of desirable
physical or mental development and conditions in an animal, e.g., a
human.
[0331] The term "modulation" is art-recognized and refers to up
regulation (i.e., activation or stimulation), down regulation
(i.e., inhibition or suppression) of a response, or the two in
combination or apart. The modulation is generally compared to a
baseline or reference that can be internal or external to the
treated entity.
[0332] "Parenteral administration", as used herein, means
administration by any method other than through the digestive tract
(enteral) or non-invasive topical routes. For example, parenteral
administration may include administration to a patient
intravenously, intradermally, intraperitoneally, intrapleurally,
intratracheally, intraossiously, intracerebrally, intrathecally,
intramuscularly, subcutaneously, subjunctivally, by injection, and
by infusion.
[0333] "Topical administration", as used herein, means the
non-invasive administration to the skin, orifices, or mucosa.
Topical administration can be delivered locally, i.e., the
therapeutic can provide a local effect in the region of delivery
without systemic exposure or with minimal systemic exposure. Some
topical formulations can provide a systemic effect, e.g., via
adsorption into the blood stream of the individual. Topical
administration can include, but is not limited to, cutaneous and
transdermal administration, buccal administration, intranasal
administration, intravaginal administration, intravesical
administration, ophthalmic administration, and rectal
administration.
[0334] "Enteral administration", as used herein, means
administration via absorption through the gastrointestinal tract.
Enteral administration can include oral and sublingual
administration, gastric administration, or rectal
administration.
[0335] "Pulmonary administration", as used herein, means
administration into the lungs by inhalation or endotracheal
administration. As used herein, the term "inhalation" refers to
intake of air to the alveoli. The intake of air can occur through
the mouth or nose.
[0336] The terms "sufficient" and "effective", as used
interchangeably herein, refer to an amount (e.g., mass, volume,
dosage, concentration, and/or time period) needed to achieve one or
more desired result(s). A "therapeutically effective amount" is at
least the minimum concentration required to effect a measurable
improvement or prevention of at least one symptom or a particular
condition or disorder, to effect a measurable enhancement of life
expectancy, or to generally improve patient quality of life. The
therapeutically effective amount is thus dependent upon the
specific biologically active molecule and the specific condition or
disorder to be treated. Therapeutically effective amounts of many
active agents, such as antibodies, are known in the art. The
therapeutically effective amounts of compounds and compositions
described herein, e.g., for treating specific disorders may be
determined by techniques that are well within the craft of a
skilled artisan, such as a physician.
[0337] The terms "bioactive agent" and "active agent", as used
interchangeably herein, include, without limitation,
physiologically or pharmacologically active substances that act
locally or systemically in the body. A bioactive agent is a
substance used for the treatment (e.g., therapeutic agent),
prevention (e.g., prophylactic agent), diagnosis (e.g., diagnostic
agent), cure or mitigation of disease or illness, a substance which
affects the structure or function of the body, or pro-drugs, which
become biologically active or more active after they have been
placed in a predetermined physiological environment.
[0338] The term "prodrug" refers to an agent, including a small
organic molecule, peptide, nucleic acid or protein, that is
converted into a biologically active form in vitro and/or in vivo.
Prodrugs can be useful because, in some situations, they may be
easier to administer than the parent compound (the active
compound). For example, a prodrug may be bioavailable by oral
administration whereas the parent compound is not. The prodrug may
also have improved solubility in pharmaceutical compositions
compared to the parent drug. A prodrug may also be less toxic than
the parent. A prodrug may be converted into the parent drug by
various mechanisms, including enzymatic processes and metabolic
hydrolysis. Harper, N.J. (1962) Drug Latentiation in Jucker, ed.
Progress in Drug Research, 4:221-294; Morozowich et al. (1977)
Application of Physical Organic Principles to Prodrug Design in E.
B. Roche ed. Design of Biopharmaceutical Properties through
Prodrugs and Analogs, APhA; Acad. Pharm. Sci.; E. B. Roche, ed.
(1977) Bioreversible Carriers in Drug in Drug Design, Theory and
Application, APhA; H. Bundgaard, ed. (1985) Design of Prodrugs,
Elsevier; Wang et al. (1999) Prodrug approaches to the improved
delivery of peptide drug, Curr. Pharm. Design. 5(4):265-287;
Pauletti et al. (1997) Improvement in peptide bioavailability:
Peptidomimetics and Prodrug Strategies, Adv. Drug. Delivery Rev.
27:235-256; Mizen et al. (1998). The Use of Esters as Prodrugs for
Oral Delivery of .beta.-Lactam antibiotics, Pharm. Biotech.
11:345-365; Gaignault et al. (1996) Designing Prodrugs and
Bioprecursors I. Carrier Prodrugs, Pract. Med. Chem. 671-696; M.
Asgharnejad (2000). Improving Oral Drug Transport Via Prodrugs, in
G. L. Amidon, P. I. Lee and E. M. Topp, Eds., Transport Processes
in Pharmaceutical Systems, Marcell Dekker, p. 185-218; Balant et
al. (1990) Prodrugs for the improvement of drug absorption via
different routes of administration, Eur. J. Drug Metab.
Pharmacokinet., 15(2): 143-53; Balimane and Sinko (1999).
Involvement of multiple transporters in the oral absorption of
nucleoside analogues, Adv. Drug Delivery Rev., 39(1-3):183-209;
Browne (1997). Fosphenytoin (Cerebyx), Clin. Neuropharmacol. 20(1):
1-12; Bundgaard (1979). Bioreversible derivatization of
drugs--principle and applicability to improve the therapeutic
effects of drugs, Arch. Pharm. Chemi. 86(1): 1-39; H. Bundgaard,
ed. (1985) Design of Prodrugs, New York: Elsevier; Fleisher et al.
(1996) Improved oral drug delivery: solubility limitations overcome
by the use of prodrugs, Adv. Drug Delivery Rev. 19(2): 115-130;
Fleisher et al. (1985) Design of prodrugs for improved
gastrointestinal absorption by intestinal enzyme targeting, Methods
Enzymol. 112: 360-81; Farquhar D, et al. (1983) Biologically
Reversible Phosphate-Protective Groups, J. Pharm. Sci., 72(3):
324-325; Han, H. K. et al. (2000) Targeted prodrug design to
optimize drug delivery, AAPS PharmSci., 2(1): E6; Sadzuka Y. (2000)
Effective prodrug liposome and conversion to active metabolite,
Curr. Drug Metab., 1(1):31-48; D. M. Lambert (2000) Rationale and
applications of lipids as prodrug carriers, Eur. J. Pharm. Sci., 11
Suppl. 2:S15-27; Wang, W. et al. (1999) Prodrug approaches to the
improved delivery of peptide drugs. Curr. Pharm. Des.,
5(4):265-87.
[0339] The term "biocompatible", as used herein, refers to a
material that along with any metabolites or degradation products
thereof that are generally non-toxic to the recipient and do not
cause any significant adverse effects to the recipient. Generally
speaking, biocompatible materials are materials which do not elicit
a significant inflammatory or immune response when administered to
a patient.
[0340] The term "biodegradable" as used herein, generally refers to
a material that will degrade or erode under physiologic conditions
to smaller units or chemical species that are capable of being
metabolized, eliminated, or excreted by the subject. The
degradation time is a function of composition and morphology.
Degradation times can be from hours to weeks.
[0341] The term "pharmaceutically acceptable", as used herein,
refers to compounds, materials, compositions, and/or dosage forms
that are, within the scope of sound medical judgment, suitable for
use in contact with the tissues of human beings and animals without
excessive toxicity, irritation, allergic response, or other
problems or complications commensurate with a reasonable
benefit/risk ratio, in accordance with the guidelines of agencies
such as the U.S. Food and Drug Administration. A "pharmaceutically
acceptable carrier", as used herein, refers to all components of a
pharmaceutical formulation that facilitate the delivery of the
composition in vivo. Pharmaceutically acceptable carriers include,
but are not limited to, diluents, preservatives, binders,
lubricants, disintegrators, swelling agents, fillers, stabilizers,
and combinations thereof.
[0342] The term "molecular weight", as used herein, generally
refers to the mass or average mass of a material. If a polymer or
oligomer, the molecular weight can refer to the relative average
chain length or relative chain mass of the bulk polymer. In
practice, the molecular weight of polymers and oligomers can be
estimated or characterized in various ways including gel permeation
chromatography (GPC) or capillary viscometry. GPC molecular weights
are reported as the weight-average molecular weight (M.sub.w) as
opposed to the number-average molecular weight (M.sub.n). Capillary
viscometry provides estimates of molecular weight as the inherent
viscosity determined from a dilute polymer solution using a
particular set of concentration, temperature, and solvent
conditions.
[0343] The term "small molecule", as used herein, generally refers
to an organic molecule that is less than 2000 g/mol in molecular
weight, less than 1500 g/mol, less than 1000 g/mol, less than 800
g/mol, or less than 500 g/mol. Small molecules are non-polymeric
and/or non-oligomeric.
[0344] The term "hydrophilic", as used herein, refers to substances
that have strongly polar groups that readily interact with
water.
[0345] The term "hydrophobic", as used herein, refers to substances
that lack an affinity for water; tending to repel and not absorb
water as well as not dissolve in or mix with water.
[0346] The term "lipophilic", as used herein, refers to compounds
having an affinity for lipids.
[0347] The term "amphiphilic", as used herein, refers to a molecule
combining hydrophilic and lipophilic (hydrophobic) properties.
"Amphiphilic material" as used herein refers to a material
containing a hydrophobic or more hydrophobic oligomer or polymer
(e.g., biodegradable oligomer or polymer) and a hydrophilic or more
hydrophilic oligomer or polymer.
[0348] The term "targeting moiety", as used herein, refers to a
moiety that binds to or localizes to a specific locale. The moiety
may be, for example, a protein, nucleic acid, nucleic acid analog,
carbohydrate, or small molecule. The locale may be a tissue, a
particular cell type, or a subcellular compartment. In some
embodiments, a targeting moiety can specifically bind to a selected
molecule.
[0349] The term "reactive coupling group", as used herein, refers
to any chemical functional group capable of reacting with a second
functional group to form a covalent bond. The selection of reactive
coupling groups is within the ability of those in the art. Examples
of reactive coupling groups can include primary amines (--NH.sub.2)
and amine-reactive linking groups such as isothiocyanates,
isocyanates, acyl azides, NHS esters, sulfonyl chlorides,
aldehydes, glyoxals, epoxides, oxiranes, carbonates, aryl halides,
imidoesters, carbodiimides, anhydrides, and fluorophenyl esters.
Most of these conjugate to amines by either acylation or
alkylation. Examples of reactive coupling groups can include
aldehydes (--COH) and aldehyde reactive linking groups such as
hydrazides, alkoxyamines, and primary amines. Examples of reactive
coupling groups can include thiol groups (--SH) and sulfhydryl
reactive groups such as maleimides, haloacetyls, and pyridyl
disulfides. Examples of reactive coupling groups can include
photoreactive coupling groups such as aryl azides or diazirines.
The coupling reaction may include the use of a catalyst, heat, pH
buffers, light, or a combination thereof.
[0350] The term "protective group", as used herein, refers to a
functional group that can be added to and/or substituted for
another desired functional group to protect the desired functional
group from certain reaction conditions and selectively removed
and/or replaced to deprotect or expose the desired functional
group. Protective groups are known to the skilled artisan. Suitable
protective groups may include those described in Greene and Wuts,
Protective Groups in Organic Synthesis, (1991). Acid sensitive
protective groups include dimethoxytrityl (DMT),
tert-butylcarbamate (tBoc) and trifluoroacetyl (tFA). Base
sensitive protective groups include 9-fluorenylmethoxycarbonyl
(Fmoc), isobutyrl (iBu), benzoyl (Bz) and phenoxyacetyl (pac).
Other protective groups include acetamidomethyl, acetyl,
tert-amyloxycarbonyl, benzyl, benzyloxycarbonyl,
2-(4-biphcnylyl)-2-propy!oxycarbonyl, 2-bromobenzyloxycarbonyl,
tert-butyl.sub.7 tert-butyloxycarbonyl,
1-carbobenzoxamido-2,2.2-trifluoroethyl, 2,6-dichlorobenzyl,
2-(3,5-dimethoxyphenyl)-2-propyloxycarbonyl, 2,4-dinitrophenyl,
dithiasuccinyl, formyl, 4-methoxybenzenesulfonyl, 4-methoxybenzyl,
4-methylbenzyl, o-nitrophenylsulfenyl,
2-phenyl-2-propyloxycarbonyl,
.alpha.-2,4,5-tetramethylbenzyloxycarbonyl, p-toluenesulfonyl,
xanthenyl, benzyl ester, N-hydroxysuccinimide ester, p-nitrobenzyl
ester, p-nitrophenyl ester, phenyl ester, p-nitrocarbonate,
p-nitrobenzylcarbonate, trimethylsilyl and pentachlorophenyl
ester.
[0351] The term "activated ester", as used herein, refers to alkyl
esters of carboxylic acids where the alkyl is a good leaving group
rendering the carbonyl susceptible to nucleophilic attack by
molecules bearing amino groups. Activated esters are therefore
susceptible to aminolysis and react with amines to form amides.
Activated esters contain a carboxylic acid ester group --CO.sub.2R
where R is the leaving group.
[0352] The term "alkyl" refers to the radical of saturated
aliphatic groups, including straight-chain alkyl groups,
branched-chain alkyl groups, cycloalkyl (alicyclic) groups,
alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted
alkyl groups.
[0353] In some embodiments, a straight chain or branched chain
alkyl has 30 or fewer carbon atoms in its backbone (e.g.,
C.sub.1-C.sub.30 for straight chains, C.sub.3-C.sub.30 for branched
chains), 20 or fewer, 12 or fewer, or 7 or fewer. Likewise, in some
embodiments cycloalkyls have from 3-10 carbon atoms in their ring
structure, e.g., have 5, 6 or 7 carbons in the ring structure. The
term "alkyl" (or "lower alkyl") as used throughout the
specification, examples, and claims is intended to include both
"unsubstituted alkyls" and "substituted alkyls", the latter of
which refers to alkyl moieties having one or more substituents
replacing a hydrogen on one or more carbons of the hydrocarbon
backbone. Such substituents include, but are not limited to,
halogen, hydroxyl, carbonyl (such as a carboxyl, alkoxycarbonyl,
formyl, or an acyl), thiocarbonyl (such as a thioester, a
thioacetate, or a thioformate), alkoxyl, phosphoryl, phosphate,
phosphonate, a hosphinate, amino, amido, amidine, imine, cyano,
nitro, azido, sulfhydryl, alkylthio, sulfate, sulfonate, sulfamoyl,
sulfonamido, sulfonyl, heterocyclyl, aralkyl, or an aromatic or
heteroaromatic moiety.
[0354] Unless the number of carbons is otherwise specified, "lower
alkyl" as used herein means an alkyl group, as defined above, but
having from one to ten carbons, or from one to six carbon atoms in
its backbone structure. Likewise, "lower alkenyl" and "lower
alkynyl" have similar chain lengths. In some embodiments, alkyl
groups are lower alkyls. In some embodiments, a substituent
designated herein as alkyl is a lower alkyl.
[0355] It will be understood by those skilled in the art that the
moieties substituted on the hydrocarbon chain can themselves be
substituted, if appropriate. For instance, the substituents of a
substituted alkyl may include halogen, hydroxy, nitro, thiols,
amino, azido, imino, amido, phosphoryl (including phosphonate and
phosphinate), sulfonyl (including sulfate, sulfonamido, sulfamoyl
and sulfonate), and silyl groups, as well as ethers, alkylthios,
carbonyls (including ketones, aldehydes, carboxylates, and esters),
--CF.sub.3, --CN and the like. Cycloalkyls can be substituted in
the same manner.
[0356] The term "heteroalkyl", as used herein, refers to straight
or branched chain, or cyclic carbon-containing radicals, or
combinations thereof, containing at least one heteroatom. Suitable
heteroatoms include, but are not limited to, O, N, Si, P, Se, B,
and S, wherein the phosphorous and sulfur atoms are optionally
oxidized, and the nitrogen heteroatom is optionally quaternized.
Heteroalkyls can be substituted as defined above for alkyl
groups.
[0357] The term "alkylthio" refers to an alkyl group, as defined
above, having a sulfur radical attached thereto. In some
embodiments, the "alkylthio" moiety is represented by one of
--S-alkyl, --S-alkenyl, and --S-alkynyl. Representative alkylthio
groups include methylthio, and ethylthio. The term "alkylthio" also
encompasses cycloalkyl groups, alkene and cycloalkene groups, and
alkyne groups. "Arylthio" refers to aryl or heteroaryl groups.
Alkylthio groups can be substituted as defined above for alkyl
groups.
[0358] The terms "alkenyl" and "alkynyl", refer to unsaturated
aliphatic groups analogous in length and possible substitution to
the alkyls described above, but that contain at least one double or
triple bond respectively.
[0359] The terms "alkoxyl" or "alkoxy" as used herein refers to an
alkyl group, as defined above, having an oxygen radical attached
thereto. Representative alkoxyl groups include methoxy, ethoxy,
propyloxy, and tert-butoxy. An "ether" is two hydrocarbons
covalently linked by an oxygen. Accordingly, the substituent of an
alkyl that renders that alkyl an ether is or resembles an alkoxyl,
such as can be represented by one of --O-alkyl, --O-alkenyl, and
--O-alkynyl. Aroxy can be represented by --O-aryl or O-heteroaryl,
wherein aryl and heteroaryl are as defined below. The alkoxy and
aroxy groups can be substituted as described above for alkyl.
[0360] The terms "amine" and "amino" are art-recognized and refer
to both unsubstituted and substituted amines, e.g., a moiety that
can be represented by the general formula:
##STR00204##
[0361] wherein R.sub.9, R.sub.10, and R'.sub.10 each independently
represent a hydrogen, an alkyl, an alkenyl,
--(CH.sub.2).sub.m--R.sub.8 or R.sub.9 and R.sub.10 taken together
with the N atom to which they are attached complete a heterocycle
having from 4 to 8 atoms in the ring structure; R8 represents an
aryl, a cycloalkyl, a cycloalkenyl, a heterocycle or a polycycle;
and m is zero or an integer in the range of 1 to 8. In some
embodiments, only one of R.sub.9 or R.sub.10 can be a carbonyl,
e.g., R.sub.9, R.sub.10 and the nitrogen together do not form an
imide. In still other embodiments, the term "amine" does not
encompass amides, e.g., wherein one of R.sub.9 and R.sub.10
represents a carbonyl. In additional embodiments, R.sub.9 and
R.sub.10 (and optionally R'.sub.10) each independently represent a
hydrogen, an alkyl or cycloalkly, an alkenyl or cycloalkenyl, or
alkynyl. Thus, the term "alkylamine" as used herein means an amine
group, as defined above, having a substituted (as described above
for alkyl) or unsubstituted alkyl attached thereto, i.e., at least
one of R.sub.9 and R.sub.10 is an alkyl group.
[0362] The term "amido" is art-recognized as an amino-substituted
carbonyl and includes a moiety that can be represented by the
general formula:
##STR00205##
[0363] wherein R.sub.9 and R.sub.10 are as defined above.
[0364] "Aryl", as used herein, refers to C.sub.5-C.sub.10-membered
aromatic, heterocyclic, fused aromatic, fused heterocyclic,
biaromatic, or bihetereocyclic ring systems. Broadly defined,
"aryl", as used herein, includes 5-, 6-, 7-, 8-, 9-, and
10-membered single-ring aromatic groups that may include from zero
to four heteroatoms, for example, benzene, pyrrole, furan,
thiophene, imidazole, oxazole, thiazole, triazole, pyrazole,
pyridine, pyrazine, pyridazine and pyrimidine, and the like. Those
aryl groups having heteroatoms in the ring structure may also be
referred to as "aryl heterocycles" or "heteroaromatics". The
aromatic ring can be substituted at one or more ring positions with
one or more substituents including, but not limited to, halogen,
azide, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl,
alkoxyl, amino (or quaternized amino), nitro, sulfhydryl, imino,
amido, phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether,
alkylthio, sulfonyl, sulfonamido, ketone, aldehyde, ester,
heterocyclyl, aromatic or heteroaromatic moieties, --CF.sub.3,
--CN; and combinations thereof.
[0365] The term "aryl" also includes polycyclic ring systems having
two or more cyclic rings in which two or more carbons are common to
two adjoining rings (i.e., "fused rings") wherein at least one of
the rings is aromatic, e.g., the other cyclic ring or rings can be
cycloalkyls, cycloalkenyls, cycloalkynyls, aryls and/or
heterocycles. Examples of heterocyclic rings include, but are not
limited to, benzimidazolyl, benzofuranyl, benzothiofuranyl,
benzothiophenyl, benzoxazolyl, benzoxazolinyl, benzthiazolyl,
benztriazolyl, benztetrazolyl, benzisoxazolyl, benzisothiazolyl,
benzimidazolinyl, carbazolyl, 4aH carbazolyl, carbolinyl,
chromanyl, chromenyl, cinnolinyl, decahydroquinolinyl,
2H,6H-1,5,2-dithiazinyl, dihydrofuro[2,3 b] tetrahydrofuran,
furanyl, furazanyl, imidazolidinyl, imidazolinyl, imidazolyl,
1H-indazolyl, indolenyl, indolinyl, indolizinyl, indolyl,
3H-indolyl, isatinoyl, isobenzofuranyl, isochromanyl, isoindazolyl,
isoindolinyl, isoindolyl, isoquinolinyl, isothiazolyl, isoxazolyl,
methylenedioxyphenyl, morpholinyl, naphthyridinyl,
octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl,
1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl,
oxazolidinyl, oxazolyl, oxindolyl, pyrimidinyl, phenanthridinyl,
phenanthrolinyl, phenazinyl, phenothiazinyl, phenoxathinyl,
phenoxazinyl, phthalazinyl, piperazinyl, piperidinyl, piperidonyl,
4-piperidonyl, piperonyl, pteridinyl, purinyl, pyranyl, pyrazinyl,
pyrazolidinyl, pyrazolinyl, pyrazolyl, pyridazinyl, pyridooxazole,
pyridoimidazole, pyridothiazole, pyridinyl, pyridyl, pyrimidinyl,
pyrrolidinyl, pyrrolinyl, 2H-pyrrolyl, pyrrolyl, quinazolinyl,
quinolinyl, 4H-quinolizinyl, quinoxalinyl, quinuclidinyl,
tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl,
tetrazolyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl,
1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl,
thianthrenyl, thiazolyl, thienyl, thienothiazolyl, thienooxazolyl,
thienoimidazolyl, thiophenyl and xanthenyl. One or more of the
rings can be substituted as defined above for "aryl".
[0366] The term "aralkyl", as used herein, refers to an alkyl group
substituted with an aryl group (e.g., an aromatic or heteroaromatic
group).
[0367] The term "carbocycle", as used herein, refers to an aromatic
or non-aromatic ring in which each atom of the ring is carbon.
[0368] "Heterocycle" or "heterocyclic", as used herein, refers to a
cyclic radical attached via a ring carbon or nitrogen of a
monocyclic or bicyclic ring containing 3-10 ring atoms, for
example, from 5-6 ring atoms, consisting of carbon and one to four
heteroatoms each selected from the group consisting of non-peroxide
oxygen, sulfur, and N(Y) wherein Y is absent or is H, O,
(C.sub.1-C.sub.10) alkyl, phenyl or benzyl, and optionally
containing 1-3 double bonds and optionally substituted with one or
more substituents. Examples of heterocyclic rings include, but are
not limited to, benzimidazolyl, benzofuranyl, benzothiofuranyl,
benzothiophenyl, benzoxazolyl, benzoxazolinyl, benzthiazolyl,
benztriazolyl, benztetrazolyl, benzisoxazolyl, benzisothiazolyl,
benzimidazolinyl, carbazolyl, 4aH-carbazolyl, carbolinyl,
chromanyl, chromenyl, cinnolinyl, decahydroquinolinyl,
2H,6H-1,5,2-dithiazinyl, dihydrofuro[2,3-b]tetrahydrofuran,
furanyl, furazanyl, imidazolidinyl, imidazolinyl, imidazolyl,
1H-indazolyl, indolenyl, indolinyl, indolizinyl, indolyl,
3H-indolyl, isatinoyl, isobenzofuranyl, isochromanyl, isoindazolyl,
isoindolinyl, isoindolyl, isoquinolinyl, isothiazolyl, isoxazolyl,
methylenedioxyphenyl, morpholinyl, naphthyridinyl,
octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl,
1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl,
oxazolidinyl, oxazolyl, oxepanyl, oxetanyl, oxindolyl, pyrimidinyl,
phenanthridinyl, phenanthrolinyl, phenazinyl, phenothiazinyl,
phenoxathinyl, phenoxazinyl, phthalazinyl, piperazinyl,
piperidinyl, piperidonyl, 4-piperidonyl, piperonyl, pteridinyl,
purinyl, pyranyl, pyrazinyl, pyrazolidinyl, pyrazolinyl, pyrazolyl,
pyridazinyl, pyridooxazole, pyridoimidazole, pyridothiazole,
pyridinyl, pyridyl, pyrimidinyl, pyrrolidinyl, pyrrolinyl,
2H-pyrrolyl, pyrrolyl, quinazolinyl, quinolinyl, 4H-quinolizinyl,
quinoxalinyl, quinuclidinyl, tetrahydrofuranyl,
tetrahydroisoquinolinyl, tetrahydropyranyl, tetrahydroquinolinyl,
tetrazolyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl,
1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl,
thianthrenyl, thiazolyl, thienyl, thienothiazolyl, thienooxazolyl,
thienoimidazolyl, thiophenyl and xanthenyl. Heterocyclic groups can
optionally be substituted with one or more substituents at one or
more positions as defined above for alkyl and aryl, for example,
halogen, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl, hydroxyl,
amino, nitro, sulfhydryl, imino, amido, phosphate, phosphonate,
phosphinate, carbonyl, carboxyl, silyl, ether, alkylthio, sulfonyl,
ketone, aldehyde, ester, a heterocyclyl, an aromatic or
heteroaromatic moiety, --CF3, and --CN.
[0369] The term "carbonyl" is art-recognized and includes such
moieties as can be represented by the general formula:
##STR00206##
[0370] wherein X is a bond or represents an oxygen or a sulfur, and
R.sub.11 represents a hydrogen, an alkyl, a cycloalkyl, an alkenyl,
an cycloalkenyl, or an alkynyl, R'.sub.11 represents a hydrogen, an
alkyl, a cycloalkyl, an alkenyl, an cycloalkenyl, or an alkynyl.
Where X is an oxygen and R.sub.11 or R'.sub.11 is not hydrogen, the
formula represents an "ester". Where X is an oxygen and R.sub.11 is
as defined above, the moiety is referred to herein as a carboxyl
group, and particularly when R.sub.11 is a hydrogen, the formula
represents a "carboxylic acid". Where X is an oxygen and R'.sub.11
is hydrogen, the formula represents a "formate". In general, where
the oxygen atom of the above formula is replaced by sulfur, the
formula represents a "thiocarbonyl" group. Where X is a sulfur and
R.sub.11 or R'.sub.11 is not hydrogen, the formula represents a
"thioester." Where X is a sulfur and R.sub.11 is hydrogen, the
formula represents a "thiocarboxylic acid." Where X is a sulfur and
R'.sub.11 is hydrogen, the formula represents a "thioformate." On
the other hand, where X is a bond, and R.sub.11 is not hydrogen,
the above formula represents a "ketone" group. Where X is a bond,
and R.sub.11 is hydrogen, the above formula represents an
"aldehyde" group.
[0371] The term "monoester" as used herein refers to an analog of a
dicarboxylic acid wherein one of the carboxylic acids is
functionalized as an ester and the other carboxylic acid is a free
carboxylic acid or salt of a carboxylic acid. Examples of
monoesters include, but are not limited to, to monoesters of
succinic acid, glutaric acid, adipic acid, suberic acid, sebacic
acid, azelaic acid, oxalic and maleic acid.
[0372] The term "heteroatom" as used herein means an atom of any
element other than carbon or hydrogen. Examples of heteroatoms are
boron, nitrogen, oxygen, phosphorus, sulfur and selenium. Other
useful heteroatoms include silicon and arsenic.
[0373] As used herein, the term "nitro" means --NO.sub.2; the term
"halogen" designates --F, --Cl, --Br or --I; the term "sulfhydryl"
means --SH; the term "hydroxyl" means --OH; and the term "sulfonyl"
means --SO.sub.2--.
[0374] The term "substituted" as used herein, refers to all
permissible substituents of the compounds described herein. In the
broadest sense, the permissible substituents include acyclic and
cyclic, branched and unbranched, carbocyclic and heterocyclic,
aromatic and nonaromatic substituents of organic compounds.
Illustrative substituents include, but are not limited to,
halogens, hydroxyl groups, or any other organic groupings
containing any number of carbon atoms, for example, 1-14 carbon
atoms, and optionally include one or more heteroatoms such as
oxygen, sulfur, or nitrogen grouping in linear, branched, or cyclic
structural formats. Representative substituents include alkyl,
substituted alkyl, alkenyl, substituted alkenyl, alkynyl,
substituted alkynyl, phenyl, substituted phenyl, aryl, substituted
aryl, heteroaryl, substituted heteroaryl, halo, hydroxyl, alkoxy,
substituted alkoxy, phenoxy, substituted phenoxy, aroxy,
substituted aroxy, alkylthio, substituted alkylthio, phenylthio,
substituted phenylthio, arylthio, substituted arylthio, cyano,
isocyano, substituted isocyano, carbonyl, substituted carbonyl,
carboxyl, substituted carboxyl, amino, substituted amino, amido,
substituted amido, sulfonyl, substituted sulfonyl, sulfonic acid,
phosphoryl, substituted phosphoryl, phosphonyl, substituted
phosphonyl, polyaryl, substituted polyaryl, C.sub.3-C.sub.20
cyclic, substituted C.sub.3-C.sub.20 cyclic, heterocyclic,
substituted heterocyclic, aminoacid, peptide, and polypeptide
groups.
[0375] Heteroatoms such as nitrogen may have hydrogen substituents
and/or any permissible substituents of organic compounds described
herein which satisfy the valences of the heteroatoms. It is
understood that "substitution" or "substituted" includes the
implicit proviso that such substitution is in accordance with
permitted valence of the substituted atom and the substituent, and
that the substitution results in a stable compound, i.e., a
compound that does not spontaneously undergo transformation, for
example, by rearrangement, cyclization, or elimination.
[0376] In a broad aspect, the permissible substituents include
acyclic and cyclic, branched and unbranched, carbocyclic and
heterocyclic, aromatic and nonaromatic substituents of organic
compounds. Illustrative substituents include, for example, those
described herein. The permissible substituents can be one or more
and the same or different for appropriate organic compounds. The
heteroatoms such as nitrogen may have hydrogen substituents and/or
any permissible substituents of organic compounds described herein
which satisfy the valencies of the heteroatoms.
[0377] In various embodiments, the substituent is selected from
alkoxy, aryloxy, alkyl, alkenyl, alkynyl, amide, amino, aryl,
arylalkyl, carbamate, carboxy, cyano, cycloalkyl, ester, ether,
formyl, halogen, haloalkyl, heteroaryl, heterocyclyl, hydroxyl,
ketone, nitro, phosphate, sulfide, sulfinyl, sulfonyl, sulfonic
acid, sulfonamide, and thioketone, each of which optionally is
substituted with one or more suitable substituents. In some
embodiments, the substituent is selected from alkoxy, aryloxy,
alkyl, alkenyl, alkynyl, amide, amino, aryl, arylalkyl, carbamate,
carboxy, cycloalkyl, ester, ether, formyl, haloalkyl, heteroaryl,
heterocyclyl, ketone, phosphate, sulfide, sulfinyl, sulfonyl,
sulfonic acid, sulfonamide, and thioketone, wherein each of the
alkoxy, aryloxy, alkyl, alkenyl, alkynyl, amide, amino, aryl,
arylalkyl, carbamate, carboxy, cycloalkyl, ester, ether, formyl,
haloalkyl, heteroaryl, heterocyclyl, ketone, phosphate, sulfide,
sulfinyl, sulfonyl, sulfonic acid, sulfonamide, and thioketone can
be further substituted with one or more suitable substituents.
[0378] Examples of substituents include, but are not limited to,
halogen, azide, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl,
hydroxyl, alkoxyl, amino, nitro, sulfhydryl, imino, amido,
phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether,
alkylthio, sulfonyl, sulfonamido, ketone, aldehyde, thioketone,
ester, heterocyclyl, --CN, aryl, aryloxy, perhaloalkoxy, aralkoxy,
heteroaryl, heteroaryloxy, heteroarylalkyl, heteroaralkoxy, azido,
alkylthio, oxo, acylalkyl, carboxy esters, carboxamido, acyloxy,
aminoalkyl, alkylaminoaryl, alkylaryl, alkylaminoalkyl, alkoxyaryl,
arylamino, aralkylamino, alkylsulfonyl, carboxamidoalkylaryl,
carboxamidoaryl, hydroxyalkyl, haloalkyl, alkylaminoalkylcarboxy,
aminocarboxamidoalkyl, cyano, alkoxyalkyl, perhaloalkyl,
arylalkyloxyalkyl, and the like. In some embodiments, the
substituent is selected from cyano, halogen, hydroxyl, and
nitro.
[0379] The term "copolymer" as used herein, generally refers to a
single polymeric material that is comprised of two or more
different monomers. The copolymer can be of any form, for example,
random, block, or graft. The copolymers can have any end-group,
including capped or acid end groups.
[0380] The term "mean particle size", as used herein, generally
refers to the statistical mean particle size (diameter) of the
particles in the composition. The diameter of an essentially
spherical particle may be referred to as the physical or
hydrodynamic diameter. The diameter of a non-spherical particle may
refer to the hydrodynamic diameter. As used herein, the diameter of
a non-spherical particle may refer to the largest linear distance
between two points on the surface of the particle. Mean particle
size can be measured using methods known in the art such as dynamic
light scattering. Two populations can be said to have a
"substantially equivalent mean particle size" when the statistical
mean particle size of the first population of particles is within
20% of the statistical mean particle size of the second population
of particles; for example, within 15%, or within 10%.
[0381] The terms "monodisperse" and "homogeneous size
distribution", as used interchangeably herein, describe a
population of particles, microparticles, or nanoparticles all
having the same or nearly the same size. As used herein, a
monodisperse distribution refers to particle distributions in which
90% of the distribution lies within 5% of the mean particle
size.
[0382] The terms "polypeptide," "peptide" and "protein" generally
refer to a polymer of amino acid residues. As used herein, the term
also applies to amino acid polymers in which one or more amino
acids are chemical analogs or modified derivatives of corresponding
naturally-occurring amino acids or are unnatural amino acids. The
term "protein", as generally used herein, refers to a polymer of
amino acids linked to each other by peptide bonds to form a
polypeptide for which the chain length is sufficient to produce
tertiary and/or quaternary structure. The term "protein" excludes
small peptides by definition, the small peptides lacking the
requisite higher-order structure necessary to be considered a
protein.
[0383] The terms "nucleic acid," "polynucleotide," and
"oligonucleotide" are used interchangeably to refer to a
deoxyribonucleotide or ribonucleotide polymer, in linear or
circular conformation, and in either single- or double-stranded
form. These terms are not to be construed as limiting with respect
to the length of a polymer. The terms can encompass known analogs
of natural nucleotides, as well as nucleotides that are modified in
the base, sugar and/or phosphate moieties (e.g., phosphorothioate
backbones). In general and unless otherwise specified, an analog of
a particular nucleotide has the same base-pairing specificity;
i.e., an analog of A will base-pair with T. The term "nucleic acid"
is a term of art that refers to a string of at least two
base-sugar-phosphate monomeric units. Nucleotides are the monomeric
units of nucleic acid polymers. The term includes deoxyribonucleic
acid (DNA) and ribonucleic acid (RNA) in the form of a messenger
RNA, antisense, plasmid DNA, parts of a plasmid DNA or genetic
material derived from a virus. An antisense nucleic acid is a
polynucleotide that interferes with the expression of a DNA and/or
RNA sequence. The term nucleic acids refers to a string of at least
two base-sugar-phosphate combinations. Natural nucleic acids have a
phosphate backbone. Artificial nucleic acids may contain other
types of backbones, but contain the same bases as natural nucleic
acids. The term also includes PNAs (peptide nucleic acids),
phosphorothioates, and other variants of the phosphate backbone of
native nucleic acids.
[0384] A "functional fragment" of a protein, polypeptide or nucleic
acid is a protein, polypeptide or nucleic acid whose sequence is
not identical to the full-length protein, polypeptide or nucleic
acid, yet retains at least one function as the full-length protein,
polypeptide or nucleic acid. A functional fragment can possess
more, fewer, or the same number of residues as the corresponding
native molecule, and/or can contain one or more amino acid or
nucleotide substitutions. Methods for determining the function of a
nucleic acid (e.g., coding function, ability to hybridize to
another nucleic acid) are well-known in the art. Similarly, methods
for determining protein function are well-known. For example, the
DNA binding function of a polypeptide can be determined, for
example, by filter-binding, electrophoretic mobility shift, or
immunoprecipitation assays. DNA cleavage can be assayed by gel
electrophoresis. The ability of a protein to interact with another
protein can be determined, for example, by co-immunoprecipitation,
two-hybrid assays or complementation, e.g., genetic or biochemical.
See, for example, Fields et al. (1989) Nature 340:245-246; U.S.
Pat. No. 5,585,245 and PCT WO 98/44350.
[0385] As used herein, the term "linker" refers to a carbon chain
that can contain heteroatoms (e.g., nitrogen, oxygen, sulfur, etc.)
and which may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49,
50 atoms long. Linkers may be substituted with various substituents
including, but not limited to, hydrogen atoms, alkyl, alkenyl,
alkynl, amino, alkylamino, dialkylamino, trialkylamino, hydroxyl,
alkoxy, halogen, aryl, heterocyclic, aromatic heterocyclic, cyano,
amide, carbamoyl, carboxylic acid, ester, thioether,
alkylthioether, thiol, and ureido groups. Those of skill in the art
will recognize that each of these groups may in turn be
substituted. Examples of linkers include, but are not limited to,
pH-sensitive linkers, protease cleavable peptide linkers, nuclease
sensitive nucleic acid linkers, lipase sensitive lipid linkers,
glycosidase sensitive carbohydrate linkers, hypoxia sensitive
linkers, photo-cleavable linkers, heat-labile linkers, enzyme
cleavable linkers (e.g., esterase cleavable linker),
ultrasound-sensitive linkers, and x-ray cleavable linkers.
[0386] The term "pharmaceutically acceptable counter ion" refers to
a pharmaceutically acceptable anion or cation. In various
embodiments, the pharmaceutically acceptable counter ion is a
pharmaceutically acceptable ion. For example, the pharmaceutically
acceptable counter ion is selected from citrate, malate, acetate,
oxalate, chloride, bromide, iodide, nitrate, sulfate, bisulfate,
phosphate, acid phosphate, isonicotinate, acetate, lactate,
salicylate, tartrate, oleate, tannate, pantothenate, bitartrate,
ascorbate, succinate, maleate, gentisinate, fumarate, gluconate,
glucaronate, saccharate, formate, benzoate, glutamate,
methanesulfonate, ethanesulfonate, benzenesulfonate,
p-toluenesulfonate and pamoate (i.e.,
1,1'-methylene-bis-(2-hydroxy-3-naphthoate)). In some embodiments,
the pharmaceutically acceptable counter ion is selected from
chloride, bromide, iodide, nitrate, sulfate, bisulfate, phosphate,
acid phosphate, citrate, malate, acetate, oxalate, acetate, and
lactate. In particular embodiments, the pharmaceutically acceptable
counter ion is selected from chloride, bromide, iodide, nitrate,
sulfate, bisulfate, and phosphate.
[0387] The term "pharmaceutically acceptable salt(s)" refers to
salts of acidic or basic groups that may be present in compounds
used in the present compositions. Compounds included in the present
compositions that are basic in nature are capable of forming a
variety of salts with various inorganic and organic acids. The
acids that may be used to prepare pharmaceutically acceptable acid
addition salts of such basic compounds are those that form
non-toxic acid addition salts, i.e., salts containing
pharmacologically acceptable anions, including but not limited to
sulfate, citrate, malate, acetate, oxalate, chloride, bromide,
iodide, nitrate, sulfate, bisulfate, phosphate, acid phosphate,
isonicotinate, acetate, lactate, salicylate, citrate, tartrate,
oleate, tannate, pantothenate, bitartrate, ascorbate, succinate,
maleate, gentisinate, fumarate, gluconate, glucaronate, saccharate,
formate, benzoate, glutamate, methanesulfonate, ethanesulfonate,
benzenesulfonate, p-toluenesulfonate and pamoate (i.e.,
1,1'-methylene-bis-(2-hydroxy-3-naphthoate)) salts. Compounds
included in the present compositions that include an amino moiety
may form pharmaceutically acceptable salts with various amino
acids, in addition to the acids mentioned above. Compounds included
in the present compositions, that are acidic in nature are capable
of forming base salts with various pharmacologically acceptable
cations. Examples of such salts include alkali metal or alkaline
earth metal salts and, particularly, calcium, magnesium, sodium,
lithium, zinc, potassium, and iron salts.
[0388] If the compounds described herein are obtained as an acid
addition salt, the free base can be obtained by basifying a
solution of the acid salt. Conversely, if the product is a free
base, an addition salt, particularly a pharmaceutically acceptable
addition salt, may be produced by dissolving the free base in a
suitable organic solvent and treating the solution with an acid, in
accordance with conventional procedures for preparing acid addition
salts from base compounds. Those skilled in the art will recognize
various synthetic methodologies that may be used to prepare
non-toxic pharmaceutically acceptable addition salts.
[0389] A pharmaceutically acceptable salt can be derived from an
acid selected from 1-hydroxy-2-naphthoic acid, 2,2-dichloroacetic
acid, 2-hydroxyethanesulfonic acid, 2-oxoglutaric acid,
4-acetamidobenzoic acid, 4-aminosalicylic acid, acetic acid, adipic
acid, ascorbic acid, aspartic acid, benzenesulfonic acid, benzoic
acid, camphoric acid, camphor-10-sulfonic acid, capric acid
(decanoic acid), caproic acid (hexanoic acid), caprylic acid
(octanoic acid), carbonic acid, cinnamic acid, citric acid,
cyclamic acid, dodecylsulfuric acid, ethane-1,2-disulfonic acid,
ethanesulfonic acid, formic acid, fumaric acid, galactaric acid,
gentisic acid, glucoheptonic acid, gluconic acid, glucuronic acid,
glutamic acid, glutaric acid, glycerophosphoric acid, glycolic
acid, hippuric acid, hydrobromic acid, hydrochloric acid,
isethionic, isobutyric acid, lactic acid, lactobionic acid, lauric
acid, maleic acid, malic acid, malonic acid, mandelic acid,
methanesulfonic acid, mucic, naphthalene-1,5-disulfonic acid,
naphthalene-2-sulfonic acid, nicotinic acid, nitric acid, oleic
acid, oxalic acid, palmitic acid, pamoic acid, pantothenic,
phosphoric acid, proprionic acid, pyroglutamic acid, salicylic
acid, sebacic acid, stearic acid, succinic acid, sulfuric acid,
tartaric acid, thiocyanic acid, toluenesulfonic acid,
trifluoroacetic, and undecylenic acid.
[0390] The term "bioavailable" is art-recognized and refers to a
form of the subject invention that allows for it, or a portion of
the amount administered, to be absorbed by, incorporated to, or
otherwise physiologically available to a subject or patient to whom
it is administered.
[0391] It will be appreciated that the following examples are
intended to illustrate but not to limit the present invention.
Various other examples and modifications of the foregoing
description and examples will be apparent to a person skilled in
the art after reading the disclosure without departing from the
spirit and scope of the invention, and it is intended that all such
examples or modifications be included within the scope of the
appended claims. All publications and patents referenced herein are
hereby incorporated by reference in their entirety.
EXAMPLES
Example 1: Synthesis, HPLC Analysis and Membrane Permeation of the
Conjugates
[0392] Synthesis and HPLC analysis of the compounds described
herein were carried out with methods disclosed in the Examples A,
1-7, and 14 of PCT Application No. PCT/US15/38569 filed Jun. 30,
2015, the contents of which are incorporated herein by
reference.
[0393] As an example, Conjugate 57 was synthesis by the following
route, which has been disclosed in Example 14 of PCT Application
No. PCT/US15/38569 filed Jun. 30, 2015:
##STR00207## ##STR00208##
[0394] Membrance permeability of Conjugate 57 was measured in
Caco-2 monolayers. The apparent permeability (Papp) was determined
to be very low in both the apical to basolateral direction and the
basolateral to apical direction.
TABLE-US-00005 Test Conc. Mean A.fwdarw.B Papp (10.sup.-6 cm/s)
Mean B.fwdarw.A Papp (10.sup.-6 cm/s) 10 uM 0.018 0.094
Example 2: Nanoparticle Formulation of Drug Conjugate
[0395] The methods of making nanoparticles comprising conjugates of
the present invention have been described in Examples, 11, 12 and
15 of PCT Application No. PCT/US15/38569 filed Jun. 30, 2015, the
contents of which are incorporated herein by reference. Various
nanoparticle formulations of Conjugate 57 such as NP4, NP8, NP11
and NP16 were prepared.
TABLE-US-00006 NP4 NP8 NP11 NP16 Process Single emulsion Single
emulsion Single emulsion Single emulsion Polymer PLA16- PLA16-
PLA16- PLA16-mPEG5/PLA-2A mPEG5/PLA-2A mPEG5/PLA-2A mPEG5/PLGA-0.2A
(50%/50%) (50%/50%) (50%/50%) (75%/25%) Oil phase 7% MeOH/74% 7.5%
MeOH/73% 7.5% MeOH/73% 7% MeOH/74% EtAc/ EtAc/19% BzOH
EtAc/19.5%BzOH EtAc/19.5% BzOH 19% BzOH Drug Conjugate 57 Conjugate
57 Conjugate 57 Conjugate 57 Wash Wash 10X with Wash 10X with Wash
10X with Wash 10X with cold water; Quench cold water; Quench cold
water; Quench cold water; Quench at 30.degree. C. water, 4X in
37.degree. C. water, 4X in 37.degree. C. water, at 30.degree. C.
water, wash 25X in ice wash 12.5X in ice wash 12.5X in ice wash 25X
in ice cold water; SPE cold water; SPE cold water; SPE cold water;
SPE Z.ave/PDI 83.89/0.235 105.4/0.198 152.8/0.42 80.93/0.063
(quenched Emulsion) Z.ave/PDI (post 76.5/0.167 101.5/0.237
69.9/0.15 78.83/0.089 TFF filtered) TDL (wt %) 9.37 8.50 11.42 7.04
ADL (wt %) 2.29 6.28 1.34 2.35 EE = ADL/TDL, % 24.5% 73.9% 11.77%
33.40% Potency, mg/mL 0.300 0.496 0.148 0.348 Conjugate 57
[0396] In addition, NP17, NP18, NP19, NP20 and NP21 comprising
Conjugate 57 were prepared.
TABLE-US-00007 NP17 NP18 NP19 NP20 NP21 Polymer PLA16- PLA16-
PLA16- PLA16- PLA16- mPEG5/PLA-2A mPEG5/PLA-2A mPEG5/PLA-2A
mPEG5/PLA-1A mPEG5/PLA-1A PLA- PLA- (50%/50%) (50%/50%) (50%/50%)
1A(50%/25%/25%) 1A(50%/40%/10%) Aqueous 9% NaCl 9% NaCl 200 mM Nal
9% NaCl 9% NaCl phase Z.ave/PDI 93.70/0.08 104.5/0.1 81.77/0.11
92.14/0.14 84.64/0.15 (post TFF altered) TDL (wt %) 9.70 9.64 10.11
5.70 15.37 ADL 1.69 1.91 2.21 5.31 2.95 (wt %) EE = 17.4% 19.8%
21.9% 93.1% 19.2% ADL/ TDL, % Potency 0.450 0.370 0.459 0.737 1.340
PRE SPE, mg/mL Conj. 57 Potency 0.187 0.165 0.276 0.459 0.320 POST
SPE, mg/mL Conj. 57
Example 3: Ki of Conjugates for Somatostatin Receptor
[0397] Two conjugates were assessed in an in vitro assay evaluating
binding to the somatostatin receptor 2 (SSTR2). A
radioligand-receptor binding assay was conducted at Eurofins
Panlabs (Taiwan) to determine the affinity of conjugates described
herein to the SSTR2. The assay measures binding of radiolabeled
ligand, [.sup.125 I] labeled somatostatin, to human SSTR2 using
membrane preparations from SSTR2 expressing CHO-K1 cells. Membranes
were incubated with radiolabeled somatostatin (0.03 nM) in the
presence of conjugate/compound starting at a dose of 10 uM using
6.times. serial dilutions to obtain a 10-pt curve. After a four
hour incubation, membranes were filtered and washed 3.times. and
counted to determine the remaining [.sup.125I] somatostatin bound
to the receptor. IC50 values were determined by a non-linear, least
squares regression analysis using MathIQ.TM. (ID Business Solutions
Ltd., UK). The Ki values were calculated using the equation of
Cheng and Prusoff (Cheng and Prusoff, Biochem. Pharmacol.
22:3099-3108, 1973) using the observed IC50 of the tested
conjugate/compound, the concentration of radioligand employed in
the assay, and the historical values for the KD of the ligand
obtained at Eurofins.
TABLE-US-00008 TABLE 5-1 Ki of conjugates 1-2 Conjugate SSTR2 Ki
(nM) 1 0.800 2 0.240 10 0.100 57 0.018 76 0.120 78 0.190
[0398] These data demonstrate that the high affinity of the peptide
for the receptor is retained after addition of the linker and drug
to the peptide.
[0399] In another study, the binding of Conjugate 57 to the five
SSTRs was measured with the same method. Conjugate 57 binds
selectively and with high affinity to SSTR2.
TABLE-US-00009 TABLE 5-2 Ki of conjugate 57 with SSTRs Somatostatin
receptor Conjugate 57 Ki (nM) SSTR1 310 SSTR2 0.018 SSTR3 19.8
SSTR4 5480 SSTR5 9.6
[0400] To further study the off-target binding of Conjugate 57, the
binding of Conjugate 57 to a panel of GPCRs (119 targets) was
measured at 1 uM concentration. Conjugate 57 has no activity
against the panel of GPCRs. The inhibition of hERG with up to 10 uM
Conjugate 57 was measured in an IonWorks Quattro assay. Conjugate
57 showed no inhibition of hERG.
Example 4: Internalization of Conjugates to Somatostatin
Receptor
[0401] Two conjugates were assessed in an in vitro assay evaluating
SSTR2. The steps outlined below provide the assay volumes and
procedure for performing agonist assays using the PathHunter
eXpress Activated GPCR Internalization cells and PathHunter
Detection Reagents generally according to the manufacturer's
recommendations. GraphPad Prism.RTM. was used to plot the agonist
dose response.
TABLE-US-00010 TABLE 6 EC.sub.50 of conjugates 1-2 Conjugate SSTR2
EC.sub.50 (nM) 1 4.4 2 35 76 3.0
[0402] These data demonstrate that the conjugates potently induce
internalization of the receptor as a mechanism for the selective
delivery of a conjugate to the cytoplasm of SSTR2 expressing
cells.
Example 5: Proliferation and Cell-Cycle Arrest in H524 Cells with
Octreotide Competition
[0403] Conjugates of the present invention were assessed in an in
vitro assay evaluating inhibition of cell proliferation. NCI-H524
(ATCC) human small cell lung cancer cells were plated in 96 well,
V-bottomed plates (Costar) at a concentration of 5,000 cells/well.
24 hours later, cells were treated with either conjugate for 2
hours and further incubated 70 hours, or for octreotide competition
experiments, treated with 100 .mu.M octreotide for 30 min, and then
treated with conjugate for 2 hours, and further incubated for 70
hours. Conjugate starting dose was 20 .mu.M and three fold serial
dilutions were done for a total of ten points. After 2 hours of
treatment, cells were spun down, the drug containing media was
removed, and fresh complete medium was added and used to resuspend
the cells, which were spun again. After removal of the wash media,
the cells were resuspended in complete medium, and then transferred
into white walled, flat bottomed 96 well plates. Cells were further
incubated for an additional 70 hours to measure inhibition of cell
proliferation. Proliferation was measured using CellTiter Glo
reagent using the standard protocol (Promega) and a Glomax
multi+detection system (Promega). Percent proliferation inhibition
was calculated using the following formula: %
inhibition=(control-treatment)/control*100. Control is defined as
vehicle alone. IC50 curves were generated using the nonlinear
regression analysis (four parameter) with GraphPad Prism 6.
IC.sub.50 values for the conjugates comprising DM1 were shown in
Table 7 below.
[0404] Proliferations of cells treated with Conjugate 57 alone and
with octreotide competition were shown in FIG. 2A. Potent activity
with or without octreotide competion had a 12.2-fold difference in
IC.sub.50.
[0405] Results of a PH3 assay measuring effect on cell-cycle arrest
that looks at phospho histone H3 (PH3) increases were shown in FIG.
2B. Competition with octreotide in the PH3 assay shows a shift
(2.6-fold) from cells treated with Conjugate 57 alone.
[0406] A similar study is carried out in H460, which is not an
SSTR2 expression cell line. Octreotide competition (+) did not
cause a difference in IC50 of the cell proliferation inhibition
compared with Conjugate 57 alone with no competition (-). Results
of cell prolifereation of H524 (Receptor +) and H460 (Receptor -)
were shown in FIG. 2C.
[0407] These data demonstrate that conjugates retain the ability to
bind to somatostatin and internalize the receptor. In some
instances this also shows that the linker is cleaved to activate
the cytotoxic payload effectively to kill the tumor cells.
Conjugates show potent effects that are receptor dependent.
Example 6: H69 Tumor DM-1 Levels
[0408] To examine the ability of conjugates of the present
invention to accumulate in tumors, a murine cancer model was used.
All mice were treated in accordance with the OLAW Public Health
Service Policy on Human Care and Use of Laboratory Animals and the
ILAR Guide for the Care and Use of Laboratory Animals. All in vivo
studies were conducted following the protocols approved by the
Blend Therapeutics Institutional Animal Care and Use Committee.
Animals were inoculated with 2.5.times.10{circumflex over ( )}6
NCI-H69 SCLC (small cell lung cancer) cells in 1:1 RPMI 1640
(Invitrogen, Carlsbad, Calif.)/Matrigel.RTM. (BD Biosciences, San
Jose, Calif.) via subcutaneous injection to the right flank. Tumors
were allowed to reach an approximate volume of .about.500 mm3.
Animals were then randomized into treatment groups of 3 animals per
time point and were dosed at 1 mg/kg (10% propylene glycol in water
for injection for free conjugates, or 10% sucrose for
nanoparticles), or 0.4 mg/kg for DM-1 (10% propylene glycol in
water for injection). The 24 hour time point was used as a
benchmark across conjugates.
[0409] Tumor DM-1 levels were determined by liquid chromatography
mass spectrometry (LC/MS-MS). Four volumes of 5 mM
6-maleimidohexanoic acid to 1 part tumor v/w was added and
homogenized for about 10-15 seconds with a handheld homogenizer. 10
.mu.L of 500 mM Tris(2-carboxyethyl)phosphine was added to 100 uL
of tumor homogenate, mixed well and incubated at room temperature
for about 5-15 min. 200-300 uL of acetonitrile was used to
precipitate proteins in tumor homogenate, samples were centrifuged
for 5 min, and supernatant was injected onto LC/MS-MS system for
DM-1 analysis. H69 tumor DM-1 levels were shown in Table 7.
TABLE-US-00011 TABLE 7 H524 cell assay results and in vivo tumor
uptake in H69 cells for conjugates H524 H524 IC.sub.50 + 100 uM H69
tumor DM-1 Conjugate IC.sub.50 (nM) octreotide (nM) levels (nM) 4
367 853 n.d. 6 234 629 n.d. 7 955 1770 n.d. 68 821 1340 n.d. 70 317
417 n.d. 72 n.d. n.d. n.d. 74 549 562 n.d. 76 120 768 62.2 76 NP7
n.d. n.d. 221 10 156 625 72.1 10 NP6 n.d. n.d. 883 35 253 1000 23.2
78 124 365 36.2 78 NP5 n.d. n.d. 223 80 152 157 91.2 82 148 867
n.d. 84 76 312 n.d. 37 44 166 n.d. 111 123 742 82.6 86 386 553 n.d.
113 1080 4920 n.d. 115 327 1495 37.1 39 2642 3578 11.8 88 80 180
n.d. 41 86 1343 n.d. 90 84 1021 n.d. 92 367 471 n.d. 94 285 1017
n.d. 96 206 397 n.d. 98 690 1121 n.d. 100 303 1055 n.d. 117 6 54
n.d. 102 335 579 n.d. 43 1165 2046 n.d. 45 345 481 n.d. 47 2129
1267 n.d. 49 69 243 n.d. 51 124 238 n.d. 12 1685 2345 n.d. 104 279
705 n.d. 14 298 877 70.1 106 400 666 n.d. 16 223 398 96.4 53 42 175
n.d. 18 1480 2160 86.3 20 241 427 n.d. 108 96 1280 n.d. 22 332 741
145 24 149 982 n.d. 26 787 1161 n.d. 55 47 395 95.3 28 669 1000
n.d. 57 136 1654 243 59 24 170 n.d. 30 470 2017 n.d. 32 310 733
n.d. 61 89 274 n.d. 63 44 168 n.d. 65 30 229 n.d. 119 2656 >5000
n.d. DM-1 90 90 31.6
Example 7: In Vitro Effect of Conjugate 57 on Tumor Cell
Proliferation
[0410] Conjugate 57 was assessed in an in vitro assay evaluating
inhibition of cell proliferation of tumor cells. A range of tumor
cell lines were selected based on reported SSTR2 mRNA levels.
Characterization of cell surface SSTR2 receptor expression was
performed by Western staining assay. Levels of Western staining
ranged from Very strong to Weak or No staining.
TABLE-US-00012 TABLE 8 Conjugate 57-treated Cell Proliferation
IC.sub.50 Cell Tumor SSTR2 SSTR2 Protein Level Proliferation line
Type mRNA (semi-quantitative) IC.sub.50 (mM) IMR32 Brain 11.69 Very
Strong 0.0008 H524 SCLC 10.34 Very Strong 0.0675 H69 SCLC 8.9
Strong 0.108 HCC33 SCLC 8.18 Strong 0.372 COR-L279 SCLC 8.21
Moderate 0.899 SKNF1 Ganglia 9.2 Weak/No staining 2.289
[0411] Activity of Conjugate 57 in proliferation assays and degree
of IC50 correlates with observed cell surface expression of SSTR2
by Wester staining.
Example 8: In Vivo Studies of Conjugate 57 in Various Tumor
Models
[0412] Conjugate 57 was assessed in an in vivo study with NCI-H69
SCLC xenografts model. A single 2 mg/kg dose of Conjugate 57 was
administered to mice bearing NCI-H69 SCLC tumors. Levels of cell
cycle arrest marker phosphohistone H3 (PH3) were measured at the
periphery, middle and core of the tumors. Phosphorylated histone H3
is correlated chromosome condensation during both mitosis and
meiosis. DM1 has been shown to increase PH3 and cause cells to
arrest in G2M phase of mitosis. Elevated levels of PH3 are seen at
all depths of the tumor through 72h as shown in FIG. 3A. A time
dependent increase in PH3 levels is shown in FIG. 3B. PH3 response
in tumors at 24 hr was shown in FIG. 3C. Histological section from
center of the tumor was shown in FIG. 4. The biological effects
from Conjugate 57 were seen deep in the tumor and distant from
blood vessels. Apoptosis marker cleaved caspase-3 (CC3) levels
after a single dose of 2 mg/kg of Conjugate 57 were shown in FIG.
5. Cell death peaks at around 3 days after dosing. These evidences
demonstrated durable response throughout tumor after a single dose
of Conjugate 57. Conjugates of the present invention can rapidly
and deeply penetrate tumor and can exert a prolonged effect on
tumor biology.
[0413] In another study, 10 mice bearing NCI-H69 tumors were given
2 doses of Conjugate 57 at 2 mg/kg each. 9 mice bearing NCI-H69
tumors were given 2 doses of Conjugate 57 at 1.3 mg/kg each. Tumor
volumes were measured and mean tumor volumes were shown in FIG. 6.
All 10 animals dosed at 2 mg/kg had no detectable tumors at study
end. Conjugate 57 More than half (5 out of 9) animals dosed at 1.3
mg/kg had no detectable tumors at study end.
[0414] In yet another study, Conjugate 57 treatment showed complete
tumor regressions in NCI-H524 small cell lung cancer model.
NCI-H524 over expresses SSTR2. Mean tumor volume data in FIG. 7
show significant regression at maximum tolerated dose (MTD) (2
mg/kg) as well as at dose 1/2 of MTD (1 mg/kg). Mean body weight
change in FIG. 8 demonstrated that Conjugate 57 is well tolerated.
There was minimal body weight loss and favorable toxicology.
[0415] In yet another study, single cycle of Conjugate 57 treatment
was compared with two cycles of standard of care combination in
NCI-H69 small cell lung cancer model. NCI-H69 bearing rats were
treated with two cycles of cctreotide+DM1, one or two cycles of
cisplatin+etoposide, one cycle of Conjugate 57. Cycle 1 was given
on Day 1, Cycle 2 on Day 8. Rats were dosed with MTD (2 mg/kg) of
Conjugate 57. Octreotide, DM1, cisplatin, and etoposide doses were
equivalent to Conjugate 57. As shown in tumor volume graph in FIG.
9, one cycle of Conjugate 57 resulted in complete regression.
Cisplatin+etoposide combination with one or two cycles failed to
cause regression. Octreotide+DM1 control showed no efficacy.
Therefore, Conjugate 57 treatment was proven to be more effective
than standard of care combinations.
[0416] In yet another study, Conjugate 57 was assessed with
NCI-H82, a low SSTR2 expressing SCLC model. Conjugate 57 was
screened at sub-MTD dose (1.2 mg/kg instead of 2 mg/kg), 2 doses at
Day 1 and Day 8, in NCI-H82 bearing rats. As shown in tumor volume
graph in FIG. 10, Conjugate 57 showed clear efficacy compared with
DM1 treatment. Increased efficacy is expected at higher tolerated
dose.
[0417] A dose response study was carried out in NIC-H524 tumor
xenograft model (SSTR2 expressing) with a single dose of Conjugate
57. Doses evaluated were 0.5 mg/kg, 1.0 mg/kg, and 2.0 mg/kg. A
single does of Conjugate 57 had a clear dose response as evidenced
by the tumor volume graph in FIG. 11A. A single dose of 2 mg/kg
lead to a significant regression. Body weight change in FIG. 11B
showed that all doses are well-tolerated.
[0418] An in vivo comparison study between Conjugate 57 and a
control conjugate (Conjugate 120, structure shown below) was
carried out in NCI-H69 SCLC model to demonstrate receptor
dependency of DM1 conjugates of the present invention. Conjugate
120 does not bind to any SSTR, because key Lys on Conjugate 120 was
blocked which blocks binding to SSTR. SSTR affinity of Conjugate 57
is 100,00 fold more than Conjugate 120.
TABLE-US-00013 Conjugate 57 Conjugate 120 Ki (nm) 0.017 1900
##STR00209##
[0419] Three doses of Conjugate 57 or Conjugate 120 (0.7 mg/kg)
were given to NCI-H69 tumor bearing rats on Day 1, Day 8 and Day
15. Tumor volumes were measured. As shown in the tumor volume graph
in FIG. 12, Conjugate 120 had no efficacy. Hence, receptor binding
of DM1 conjugates of the present invention drives efficacy in vivo.
There is no efficacy when receptor binding is blocked.
Example 9: Pharmacokinetics of Conjugate 57
[0420] In this example, plasma pharmacokinetics of Conjugate 57 was
studied in mouses, rats and dogs. Half-life, maximum plasma drug
concentration (Cmax), drug clearance (CL), area under the curve
time curve from time 0 to the last sampling time (AUC 0-t), and
apparent volume of distribution at steady state (Vss) were
measured.
TABLE-US-00014 TABLE 9 Conjugate 57 plasma pharmacokinetics in
mouse, rat and dog Parameters Units Mouse Rat Dog Dose mg/kg 2 1.5
0.1 Dose umol/kg 1.120 0.840 0.056 t1/2 h 12.20 8.07 2.86 Cmax uM
5.93 4.69 0.730 CL mL/kg/niin 2.32 4.99 1.39 AUC 0-t uM*h 7.30 2.77
0.619 Vss mL/kg 963 594 224
[0421] As demonstrated by parameters in Table 9, mean concentration
curves in FIG. 13, and log clearance/log body weight curve in FIG.
14, consistent relatively long half-life, low plasma clearance and
low volume of distribution were observed across all three species
tested. Allometric scaling shows high correlation of the clearance
in tested species and predicts low clearance in human.
[0422] Plasma protein bindings were also measured and results were
shown in Table 10. Plasma protein binding is not concentration
dependent and is consistent across species.
TABLE-US-00015 TABLE 10 Conjugate 57 plasma protein binding in
mouse, rat and dog Plasma protein binding Mouse Rat Dog Human Free
fraction at 1 uM (%) 8.2 6.3 4.4 7.8 Free fraction at 10 uM (%) 9.4
7.4 3.3 7.8
[0423] It is predicted that Conjugate 57 will be maintained in
human plasma to accumulate in tumors and achieve efficacy.
[0424] In a further study, the potential for Conjugate 57 to
inhibit cytochrome P450 (CYP) was tested across 7 isozymes of CYP
enzymes. For all of these CYP isozymes, the IC50 was determined to
exceed 10 uM, indicating Conjugate 57 does not inhibit CYP enzymes.
The data also indicate Conjugate 57 presents no risk for causing
drug-drug interactions (DDIs) by inhibiting the CYP clearance of
other drugs. Lack of DDIs is critical when developing combination
therapies.
TABLE-US-00016 TABLE 11 IC50 of Conjugate 57 on CYP isozymes
Isozyme IC50 (.mu.M) CYP3A4 Midazolam >10 CYP3A4 Testosterone
>10 CYP2C9 >10 CYP2D6 >10 CYP1A2 >10 CYP2C8 >10
CYP2B6 >10 CYP2C19 >10
Example 10: Toxicity Studies of Conjugate 57
[0425] Single dose exploratory toxicity studies in SD female rat
(dose 0.5 mg/kg to 1.5 mg/kg) for 7-10 days were carried out.
Clinical observations, body weight, clinical blood chemistry,
histopathology, and complete blood counts were assessed. In the
10-day study, DM1 (0.4 mg/kg) was compared to Conjugate 57 at an
equivalent dose of DM1 (1.0 mg/kg of conjugate) and at a 50% higher
dose (1.5 mg/kg of conjugate). Conjugate 57 demonstrated
significantly improved tolerability versus DM1. DM1 (0.4 mg/kg)
dosed rats had to be euthanized on day 5 because they were
moribund.
TABLE-US-00017 TABLE 12 Weight changes in SD rats treated with DM1
or Conjugate 57 Day 5 weight Day 10 weight Group change (%) change
(%) Vehicle -0.73 -0.87 DM1 (0.4 mg/kg) -18 --* Conjugate 57 (1.0
mg/kg) -0.73 +1.8 Conjugate 57 (1.5 mg/kg) -5.9 +2
[0426] At day 5, DM1 treated animals had lost a significant amount
of weight. Conjugate 57 treated animals had no body weight change
in the 1.0 mg/kg group and a minor weight loss in the 1.5 mg/kg
group. At day 10, both Conjugate 57 groups had normal body
weights.
[0427] Decreased white blood cell (WBC) count is a known dose
limiting toxicity of DM1. WBC count was tracked in all groups.
Results were shown in FIG. 15. Conjugate 57 dosed at 1.0 mg/kg and
1.5 mg/kg were well tolerated with no significant changes in
complete blood count (CBC) and WBC count. In contrast, DM1 showed
dramatic decreases in WBC count.
[0428] Liver toxicity is also a know dose limiting toxicity of DM1.
Alanine transaminase (ALT) and aspartate aminotransferase (AST) are
markers of liver toxicity and were measured in all groups. Results
were shown in FIGS. 16A and 16B. Conjugate 57 at 1.0 mg/kg showed
no effects on AST and ALT. The 1.5 mg/kg dose group showed no
effect on ALT and slightly elevated AST levels at day 7 that were
returned to normal by day 10. On the contrast, DM1 at 0.4 mg/kg
showed dramatic increases in AST and ALT at day 5. Histopathology
for Conjugate 57 groups indicated that 1.0 and 1.5 mg/kg doses were
associated with minimal to mild liver and kidney findings that were
typical of reversible changes.
[0429] Therefore, Conjugate 57 has favorable toxicology on body
weight, clinical blood chemistry and liver function.
Example 11: Identifying SSTR2 Expressing Tumors
[0430] Patient selection is carried out with approved imaging agent
.sup.111Indium-pentetreotide that is marketed and used clinically.
Planar gamma camera or single positron emission computed tomograph
is used to image patient 4 hours and 24 hours after administration.
The scintigraphic localization of primary and metastatic
neuroendocrine tumors bearing somatostatin receptors can be
indicated.
[0431] Binding profiles of Conjugate 57 and Octreoscan (Indium-111
pentetreotide, literature values shown) have been compared.
Conjugate 57 has higher affinity for SSTR2 and a similar SSTR
subtype binding profile to Octreoscan.
TABLE-US-00018 TABLE 13 Ki of Conjugate 57 and Octreoscan with
SSTRs Somatostatin receptor Conjugate 57 Ki (nM) Octreoscan Ki (nM)
SSTR1 310 >10,000 SSTR2 0.0177 22 SSTR3 19.8 182 SSTR4 5480
>1,000 SSTR5 9.6 237
[0432] Patient selection is also carried out with
immunohistochemical (IHC) staining with SSTR2 antibodies. SSTR2
expression can be measured by staining intensity and distriction.
Various cell lines including H69, H526, Calu-6, H69, H524, H82,
HCC-33 and IMR-32 were studied with IHC staining of SSTR2. Staining
images were shown in FIG. 17. Stain intensity and distribution were
shown in Table 14.
TABLE-US-00019 TABLE 14 Xenograft stain intensity and distribution
Xenograph Stain instensity Distribution H82 2 3 H524 3 3 H69 2 2
Calu-6 0 0 Intensity: 0-3 Distribution: 0-3 (% positive cells, 0,
25-50, 50-75 and 75-100)
Example 12: Studies of Effects of Conjugate with NCI-H69 Model
[0433] PD studies were carried out with H69 model to determine the
in vivo response of conjugate effects on tumor cells and
timing/peak response. Conjugate 57 and Conjugate 57 in
nanoparticles (Conjugate 57/NP20) were tested at 2 mg/kg. NP20
formulation has been described in EXAMPLE 2. Western blot and IHC
staining were carried out to measure PH3 and CC3 levels.
[0434] PH3 is correlated chromosome condensation during both
mitosis and meiosis. DM1 has been shown to increase PH3 and cause
cells to arrest in G2M phase of mitosis. As shown in Western Blot
results in FIG. 18A, the peak response for PH3 occurs at 48 hours
for both the conjugate and the conjugate in the nanoparticle. IHC
results in FIG. 18B showed that PH3 signal in treated samples was
significantly higher than vehicle; PH3 signal peaked at 48 hours
for Conjugate 57 and 72 hours for Conjugate 57/NP20; Conjugate 57
had a higher PH3 peak level than Conjugate 57/NP20. PH3 level was
steady for Conjugate 57/NP20 samples.
[0435] CC3 is a marker of apoptosis. It is the executioner of
apoptosis and tightly regulated. A peak in activity is seen for
both Conjugate 57 and Conjugate 57/NP20 at 72 hours (FIG. 19). The
activity of Conjugate 57 is stronger as compared to Conjugate
57/NP20, consistent with the PH3 results.
[0436] Average tumor volumes with Conjugate 57 and Conjugate
57/NP20 treatments were shown in FIG. 20. Table 15 showed tumor
growth inhibition % (TGI %) of the treatments. Tumor inhibitions
were above 95%, almost complete tumor regression, for Conjugate 57
dosed at 2.0 mg/kg and Conjugate 57/NP20 dosed at 3.0 mg/kg.
TABLE-US-00020 TABLE 15 Tumor growth inhibition % of various
treatments TGI % TGI % TGI % TGI % TGI % Treatment Day 8 Day 11 Day
14 Day 19 Day 22 Conjugate 57 50.1 61.4 60.4 63 58.4 1 mg/kg
Conjugate 57 63.8 82.8 87.9 95.5 97.8 2 mg/kg Conjugate 51.8 71.2
70.4 72 71.7 57/NP20 1.5 mg/kg Conjugate 58.1 81.7 86.3 97.2 98.4
57/NP20 3.0 mg/kg
[0437] Fold change of PH3 and CC3 response to Conjugate 57 in H69
was shown in FIG. 21. Cell arrest as indicated by PH3 levels peaked
at 48 hr and apoptosis as indicated by CC3 levels peaked at 72
hr.
[0438] Histological staining of PH3 and CC3 in periphery, middle
and core of H69 tumor after Conjugate 57 treatment was shown in
FIG. 22A and FIG. 22B. The periphery sample was taken from roughly
the outside 1/3 of the tumor. The core sample was taken from
roughly the center 1/3 of the tumor. The middle sample was taken
from roughly 1/3 in between these locations. Using a 40.times.
high-powered objective, positively stained cells were counted, one
field per animal, 3 animals per treatment group. Each field was
roughly 500 .mu.m in size. PH3-positive cell numbers in periphery,
middle and core of the tumor were shown in Table 16A. CC3-positive
cell numbers in periphery, middle and core of the tumor were shown
in Table 16B. In general, the PH3 staining was strongest on the
periphery and decreased as you moved towards the center of the
tumor. For CC3, the more intense staining was seen in the center of
the tumor.
TABLE-US-00021 TABLE 16A Number of cells with positive PH3 stain
Treatment Periphery Middle Core Periphery Middle Core Vehicle- 24 h
62.0 47.3 17.0 3.6 3.3 0.6 Conj. 57- 24 h 158.3 122.3 74.7 20.1
16.3 10.3 Vehicle- 72 h 57.3 42.3 20.0 3.8 2.6 2.3 Conj. 57 -72 h
215.7 144.3 113.0 6.4 6.9 5.7
TABLE-US-00022 TABLE 16B Number of cells with positive CC3 stain
Treatment Periphery Middle Core Periphery Middle Core Vehicle- 24 h
3.0 10.0 23.7 1.0 0.6 2.9 Conj. 57- 24 h 9.7 27.0 50.3 1.8 3.8 8.5
Vehicle- 72 h 5.0 16.3 25.0 0.6 1.5 2.1 Cong. 57-72 h 41.0 72.0
106.7 2.1 2.1 5.5
[0439] These tumor penetration studies showed that the conjugates
of the present invention can have an effect on centrally located
tumor cells. Conjugates of the present invention may penetrate to
the core of the tumor.
Example 13: In Vivo Effects of Conjugate on HCC-33 and Other
Models
[0440] The efficacy of Conjugate 57 was studied with HCC-33 (SCLC)
xenografts. Conjugate 57 was dosed on Day 1 and Day 8. Tumor
volumes were shown in FIG. 23. Tumor growth inhibition results were
shown in Table 17.
TABLE-US-00023 TABLE 17 Tumor growth inhibition % of HCC-33 with
Conjugate 57 treatments TGI % TGI % TGI % TGI % TGI % TGI % TGI %
TGI % Treatment Day 5 Day 8 Day 12 Day 16 Day 20 Day 23 Day 27 Day
30 Conjugate 57 47 74.8 88.2 96.2 98.3 99.1 99.5 99.9 2 mg/kg
Conjugate 57 46.2 71.3 87.2 96.3 98.1 99.2 99.6 99.6 1 mg/kg
[0441] Tumor regression was almost 100% in both groups. Body
weights increased in both groups.
[0442] Similar studies are carried out in IMR-32 neuroblastoma
tumor model and other tumors including neuroendocrine, liver,
Medullary Thyroid, and pancreatic neuroendocrine tumors.
Example 14: Effects of Nanoparticle Formulation on Conjugate In
Vitro Stability and In Vivo PK
[0443] Conjugate 57 was formulated with nanoparticle compositions
NP4, NP8, NP11 and NP16 described in EXAMPLE 2. FIG. 24A showed in
vitro Conjugate 57 plasma release at 37.degree. C. with Conjugate
57 alone and in various nanopartical compositions. FIG. 24A
indicated that more Conjugate 57 remains in plasma when it is in
nanoparticle formulations. Conjugate 57 in NP8 formulation remained
in plasma 100% up to 8 hours. FIG. 24B showed in vivo Conjugate 57
PK. Conjugate 57 concentration reduced slowest in NP8 formulation.
The data demonstrated that nanoparticles are tunable for different
in vitro release kinetics. Tunable in vitro release is directly
translatable to in vivo rat pharmacokinetics. Nanoparticle exposure
(AUC and t1/2) in rat PK correlates with in vitro plasma
release.
Example 15: SSTR2 Receptor Internalization by Conjugate 57
[0444] SSTR2 receptor internalization was studied using Conjugate
57 in a highly expressing SSTR2 positive (SSTR2+) tumor xenograft:
H524 MD tumor xenograft. Vehicle (0.1% Solutol/5% Mannitol),
Conjugate 57 at 2 mg/kg, scrambled control (BT-984) at 2 mg/kg, and
Octreotide at 1.4 mg/kg (ligand alone) were given to SSTR2+H524-MD
tumor xenografts (n=3/group). Timepoints--0 hr (Vehicle), 15 mins,
1 hr, 4 hr, 24 hr and 72 hrs. SSTR2 scoring was done by
immunohistochemistry (IHC) staining.
[0445] FIG. 25A showed SSTR2 receptor internalization intensity. As
shown in FIG. 25A, after Conjugate 57 treatment, SSTR2 receptors
located on the membrane in the top left figure and became mostly
cytoplasmic in the lower right figure. In this intensity of
staining analysis, Conjugate 57 treatment yielded significantly
different results from scrambled peptide version of compound 57
(BT-984) and naive at 1 hr, 4 hr, and 72 hours. Additionally, at 72
hours, Conjugate 57 treatment yielded significantly different
results from Octreotide.
[0446] FIG. 25C showed levels of SSTR2 internalization
distribution. In the lower right image, SSTR2 internalization
reached >66%. In this distribution of staining analysis,
Conjugate 57 treatment yielded significantly different results from
BT-984 and naive at 4 hr, 24 hr, and 72 hours. Additionally, at 72
hours, Conjugate 57 treatment yielded significantly different
results from Octreotide.
[0447] FIG. 25B showed SSTR2 internationalization in H524-MD tumor
xenografts at different times. FIG. 25D showed SSTR2 internal
cellular distribution in H514-MD tumor xenografts at different
times. The `*` in FIG. 25B and FIG. 25D showed there was
significant difference with Conjugate 57 v.s. BT-984 and naive
(*p<0.05) with Dunn's multiple comparison test. The `+` in FIG.
25B and FIG. 25D showed there was significant difference with
Conjugate 57 v.s. octreotide (+p<0.05) with Dunn's multiple
comparison test.
[0448] Therefore, treatment of Conjugate 57 displayed significant
receptor internalization/distribution supporting the hypothesis
that the compound is actively targeting the receptor in vivo
(unlike scrambled). Binding of the SSTR2 receptor via the
octreotate ligand of Conjugate 57 induces internalization of the
SSTR2 receptor and internalizes the DM-1 payload. Surprisingly,
Conjugate 57 caused more SSTR2 internalization than octreotide
alone.
Example 16: Neuroblastoma Treated by Conjugate 57
[0449] Neuroblastoma is a neuroendocrine tumor that most frequently
originates in the adrenal glands. Neuroblastoma cell line IMR-32
was chosen for this study.
[0450] First, an in vitro competitive assay was conducted where
IMR-32 cells were treated with Conjugate 57 in the absence or
presence of an excess of octreotide. Conjugate 57 inhibited the
growth of IMR-32 cells. Pre-incubation with octreotide affected the
inhibition.
[0451] Further, mice bearing passage 3 IMR-32 tumors were dosed
with Conjugate 57 either at 2.0 mg/kg or 1.5 mg/kg once a week for
two weeks with a vehicle negative control. Moderate body weight
loss was observed in the 2.0 mpk group after the second dosing
event, with an average of 8.0%. The 1.5 mpk group only lost an
average of 2.0%. All mice recovered once dosing was complete. As
shown in FIG. 26B, tumor regressions were observed in both
treatment groups. In both treatment groups, 10 out of 10 mice
showed complete regression.
Example 17: Efficacy of Conjugate 57 in Treating SCLC
[0452] HCC-33 (small cell lung cancer) xenograft was chosen to
study efficacy of Conjugate 57. In some groups, Conjugate 57 was
given at 1.0 mg/kg, 0.5 mg/kg or 0.33 mg/kg every week for 30 days,
a total of four doses for each animal. In some other groups,
Conjugate 57 was also given at 0.5 mg/kg or 0.25 mg/kg twice a week
for 30 days, a total of 8 total doses for each animal.
[0453] Study results established that multiple doses were well
tolerated. Body weights in all groups were good. Tumor regression
results were shown in Table 18 below and FIG. 27.
TABLE-US-00024 TABLE 18 TGI % of HCC-33 xenograft Conj. 57 TGI %
Treatment Day 4 Day 8 Day 11 Day 15 Day 18 Day 22 Day 25 Day 29 1.0
mg/kg 25.8 69.9 84.4 93.6 97.4 99.2 99.8 99.7 0.5 mg/kg 1.6 60.3
68.8 82.7 87.1 91.1 93.6 89.5 0.33 mg/kg 2.1 34.2 48 62.4 73.8 79
83.4 78.5 0.5 mg/kg 0.5 61.6 78.3 91.8 96.2 97.6 99.1 99.2 2x/wk
0.25 mg/kg -12.5 50.4 67.3 85.8 92.3 95.8 97.2 97.8 2x/wk
Example 18: Tumor Penetrations of Conjugates and Antibody Drug
Conjugates (ADCs)
[0454] Antibody drug conjugates (ADCs) typically have a molecular
weight of around 150 KDa and have poor solid tumor penetration.
Tumor penetrations of conjugates of the present invention and ADCs
were compared in a fluorescence study conducted in NCI-H69 small
cell lung cancer (SCLC) xenografts. Small cell lung cancer tumors
over-express somatostatin and neural cell adhesion molecule (NCAM)
receptors. Therefore, conjugates of the present invention
comprising a targeting moiety that binds to SSTR can bind to the
surface of SCLC cells. NCAM antibodies also bind to surface of SCLC
cells.
[0455] A Cy7 fluorescent tag was attached to the peptide of
Conjugate 57 to make a fluorescent Conjugate 120. A 680XL
fluorochrome tag was attached to an NCAM antibody to produce a
fluorescent antibody.
##STR00210##
[0456] A single dose of Conjugate 120 and the 680XL tagged NCAM
antibody was given to animals bearing NCI-H69 xenografts. On day 4,
fluorescence images of the NCI-H69 xenografts were taken. As shown
in FIG. 28, Conjugate 120 already penetrated tumor core and beyond
periphery at day 4. On the contrary, the antibody only had medium
to low concentrations inside the tumor at day 4. Actually, the
antibody requires 7 days to show penetration at the tumor core. By
day 7, many ADC's dissociate from their payloads. Therefore,
conjugates of the present invention rapidly penetrate the core of
SSTR2 expressing tumors. Conjugates of the present invention
penetrate faster and deeper than antibodies and ADCs targeting the
same type of tumor.
Example 19: Breast Cancer Treated with Conjugates of the Present
Invention
[0457] Tumor tissue specimen are obtained from patients with
primary carcinoma of the breast. Corresponding normal tissues are
also obtained. Quantative evaluation of SSTR2 mRNA is measured in
the tumor tissues and normal tissues with real-time PCR. SSTR2 is
also detected with immunocytochemical methods using
subtype-specific antibodies. It is demonstrated that SSTR2 are
overexpress in breast cancer.
[0458] In an in vitro study, Conjugate 57 is given to MCF-7 breast
cancer cells. Cell proliferation of the MCF-7 cells are measured.
Conjugate 57 reduces the proliferation of MCF-7 cells.
* * * * *