U.S. patent application number 10/400162 was filed with the patent office on 2003-12-25 for method of modifying the release profile of sustained release compositions.
This patent application is currently assigned to Alkermes Controlled Therapeutics, Inc.. Invention is credited to Dasch, James R., I. Riley, M. Gary.
Application Number | 20030236192 10/400162 |
Document ID | / |
Family ID | 25268316 |
Filed Date | 2003-12-25 |
United States Patent
Application |
20030236192 |
Kind Code |
A1 |
Dasch, James R. ; et
al. |
December 25, 2003 |
Method of modifying the release profile of sustained release
compositions
Abstract
The present invention relates to a method for the sustained
release in vivo of a biologically active agent comprising
administering to a subject in need of treatment an effective amount
of a sustained release composition comprising a biocompatible
polymer having the biologically active agent incorporated therein,
and a bisphosphonate wherein the bisphosphonate compound is present
in an amount sufficient to modify the release profile of the
biologically active agent from the sustained release composition.
Pharmaceutical compositions suitable for use in the method of the
invention are also disclosed.
Inventors: |
Dasch, James R.; (Needham,
MA) ; I. Riley, M. Gary; (Cambridge, MA) |
Correspondence
Address: |
HAMILTON, BROOK, SMITH & REYNOLDS, P.C.
530 VIRGINIA ROAD
P.O. BOX 9133
CONCORD
MA
01742-9133
US
|
Assignee: |
Alkermes Controlled Therapeutics,
Inc.
Cambridge
MA
|
Family ID: |
25268316 |
Appl. No.: |
10/400162 |
Filed: |
March 25, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10400162 |
Mar 25, 2003 |
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09835001 |
Apr 13, 2001 |
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6558702 |
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Current U.S.
Class: |
514/7.7 ;
514/1.1; 514/21.2 |
Current CPC
Class: |
A61K 45/06 20130101;
A61K 9/1694 20130101; A61K 31/7088 20130101; A61K 9/5084 20130101;
A61K 31/663 20130101; A61K 9/0024 20130101; A61K 31/7088 20130101;
A61K 38/1816 20130101; Y10S 514/964 20130101; A61K 9/1652 20130101;
A61K 31/663 20130101; A61K 9/1647 20130101; A61K 2300/00 20130101;
A61K 2300/00 20130101 |
Class at
Publication: |
514/12 |
International
Class: |
A61K 038/00 |
Claims
What is claimed is:
1. A method for the sustained release in vivo of a biologically
active agent comprising administering to a subject in need of
treatment an effective amount of a sustained release composition
comprising a biocompatible polymer having a biologically active
agent incorporated therein, and a bisphosphonate compound wherein
the bisphosphonate compound is present in an amount sufficient to
modify the release profile of the biologically active agent from
the sustained release composition.
2. The method of claim 1, wherein the bisphosphonate compound is
co-incorporated into the sustained release composition.
3. The method of claim 1, wherein the bisphosphonate compound is
separately incorporated into a second biocompatible polymer.
4. The method of claim 3, wherein the second biocompatible polymer
is the same as the biocompatible polymer of the sustained release
composition.
5. The method of claim 3, wherein the second biocompatible polymer
is different from the biocompatible polymer of the sustained
release composition.
6. The method of claim 1, wherein the bisphosphonate compound is
unencapsulated but comingled with the sustained release
composition.
7. The method of claim 1 wherein the biocompatible polymer of the
sustained release composition is selected from poly(lactides),
poly(glycolides), poly(lactide-co-glycolides), poly(lactic acid)s,
poly(glycolic acid)s, polycarbonates, polyesteramides,
polyanhydrides, poly(amino acids), polyorthoesters,
poly(dioxanone)s, poly(alkylene alkylate)s, copolymers of
polyethylene glycol and polyorthoester, polyurethanes, blends
thereof, and copolymers thereof.
8. The method of claim 7 wherein the biocompatible polymer is a
poly(lactide-co-glycolide).
9. The method of claim 1 wherein the bisphosphonate is alendronate,
risendronate, pamidronate, etidronate, tiludronate or a combination
thereof.
10. The method of claim 1, wherein the sustained release
composition is in the form of microparticles.
11. The method of claim 1 wherein the biologically active agent is
a protein, a peptide or a nucleic acid.
12. The method of claim 1 wherein the biologically active agent is
a protein.
13. The method of claim 12 wherein the protein is
erythropoietin.
14. A pharmaceutical composition comprising: a) a sustained release
composition comprising a biocompatible polymer having an effective
amount of a biologically active agent incorporated therein; and b)
a bisphosphonate compound, wherein the bisphosphonate compound is
present in an amount sufficient to modify the release profile of
the biologically active agent from the sustained release
composition.
15. The pharmaceutical composition of claim 14, wherein the
bisphosphonate compound is co-incorporated into the sustained
release composition.
16. The pharmaceutical composition of claim 14, wherein the
bisphosphonate compound is separately incorporated into a second
biocompatible polymer.
17. The pharmaceutical composition of claim 16, wherein the second
biocompatible polymer is the same as the biocompatible polymer of
the sustained release composition.
18. The phamaceutical composition of claim 16, wherein the second
biocompatible polymer is different from the biocompatible polymer
of the sustained release composition.
19. The pharmaceutical composition of claim 14, wherein the
bisphosphonate compound is unencapusulated but comingled with the
sustained release composition.
20. The pharmaceutical composition of claim 14 wherein the
biocompatible polymer of the sustained release composition is
selected from poly(lactides), poly(glycolides),
poly(lactide-co-glycolides), poly(lactic acid)s, poly(glycolic
acid)s, polycarbonates, polyesteramides, polyanhydrides, poly(amino
acids), polyorthoesters, poly(dioxanone)s, poly(alkylene
alkylate)s, copolymers of polyethylene glycol and polyorthoester,
polyurethanes, blends thereof, and copolymers thereof.
21. The pharmaceutical composition of claim 20 wherein the
biocompatible polymer is a poly(lactide-co-glycolide).
22. The pharmaceutical composition of claim 14 wherein the
bisphosphonate compound is alendronate, risendronate, pamidronate,
etidronate, tiludronate or a combination thereof.
23. The pharmaceutical composition of claim 14, wherein the
sustained release composition is in the form of microparticles.
24. The pharmaceutical composition of claim 14, wherein the
biologically active agent is a protein, a peptide or a nucleic
acid.
25. The pharmaceutical composition of claim 14, wherein the
biologically active agent is a protein.
26. The pharmaceutical composition of claim 25, wherein the protein
is erythropoietin.
Description
RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 09/835,001, filed Apr. 13, 2001.
[0002] The entire teachings of the above application are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0003] Many illnesses or conditions require administration of a
constant or sustained level of a medicament or biologically active
agent to provide the most effective prophylactic or therapeutic.
This may be accomplished through a multiple dosing regimen or by
employing a system that releases the medicament in a sustained
fashion.
[0004] Attempts to sustain medication levels include the use of
biodegradable materials, such as polymeric matrices, containing the
medicament. The use of these matrices, for example, in the form of
microparticles or microcamers, provides sustained release of
medicaments by utilizing the inherent biodegradability of the
polymer. The ability to provide a sustained level of medicament can
result in improved patient compliance.
[0005] However, these sustained release devices can exhibit high
release of active agent over the first twenty-four hours, often
referred to as a burst. In some instances this burst can result in
an undesirable increase in the levels of biologically active agent
and minimal release of agent thereafter. In addition, due to the
high solution concentration of medicament within and localized
around these sustained release devices, the medicament can
aggregate thereby increasing immunogenicity in vivo and interfering
with the desired release profile for the medicament.
[0006] Therefore, a need exists to exert additional control over
the release profile of sustained release compositions by, for
example, reducing the burst of agent and/or providing an improved
release such as a longer period of release.
SUMMARY OF THE INVENTION
[0007] The present invention is based upon the unexpected discovery
that the release profile of a biologically active agent from a
sustained release composition comprising a biocompatible polymer
and the biologically active agent incorporated therein can be
modified such as by prolonging the period of release of agent when
a bisphosphonate compound is co-administered.
[0008] Accordingly, the present invention relates to a method for
the sustained release in vivo of a biologically active agent
comprising administering to a subject in need of treatment an
effective amount of a sustained release composition comprising a
biocompatible polymer having the biologically active agent
incorporated therein, and a bisphosphonate wherein the
bisphosphonate is present in an amount sufficient to modify the
release profile of the biologically active agent from the sustained
release composition.
[0009] In one embodiment, the bisphosphonate compound can be
co-incorporated into the sustained release composition comprising
the biocompatible polymer and the biologically active agent
incorporated therein.
[0010] In another embodiment, the bisphosphonate compound can be
separately incorporated into a second biocompatible polymer. The
biocompatible polymer can be the same or different from the first
biocompatible polymer which has the biologically active agent
incorporated therein.
[0011] In yet another embodiment, the bisphosphonate compound can
be present in an unencapsulated state but comingled with the
sustained release composition. For example, the bisphosphonate can
be solubilized in the vehicle used to deliver the sustained release
composition. Alternatively, the bisphosphonate compound can be
present as a solid suspended in an appropriate vehicle. Further,
the bisphosphonate can be present as a powder which is comingled
with the sustained release composition.
[0012] The invention described herein also relates to
pharmaceutical compositions suitable for use in the invention. In
one embodiment, the pharmaceutical composition comprises a
sustained release composition comprising a biocompatible polymer
having an effective amount of a biologically active agent
incorporated therein, and an amount of bisphosphonate compound
sufficient to modify the release profile of the biologically active
agent from the sustained release composition.
[0013] In one embodiment, the bisphosphonate compound can be
co-incorporated into the sustained release composition comprising
the biocompatible polymer and the biologically active agent
incorporated therein.
[0014] In another embodiment, the pharmaceutical composition
comprises the sustained release composition comprising a first
biocompatible polymer having incorporated therein an effective
amount of a biologically active agent and a second biocompatible
polymer having incorporated therein an amount of bisphosphonate
which modifies the release profile of the biologically active agent
from the first polymer. In a particular embodiment, the first and
second polymers are the same type of polymer. In another
embodiment, the first and second polymers are different.
[0015] In yet another embodiment, the bisphosphonate compound can
be present in the pharmaceutical composition in an unencapsulated
state. For example, the bisphosphonate compound can be comingled
with the sustained release composition. In one embodiment, the
bisphosphonate can be solubilized in the vehicle used to deliver
the pharmaceutical composition. Alternatively, the bisphosphonate
compound can be present as a solid suspended in an appropriate
vehicle useful for delivering the pharmaceutical composition.
Further, the bisphosphonate can be present as a powder which is
comingled with the sustained release composition.
[0016] Without being bound by a particular theory, it is believed
that at least in part the effects of the bisphosphonates can be
related to a reduction in the amount of inflammatory cellular
reaction which can occur in the area of administration of the
sustained release composition. This reaction, although clinically
insignificant, is well characterized as a foreign body response,
and can be realized with most foreign materials.
[0017] The present invention also relates to a composition for the
sustained release of bisphosphonates. The sustained release
composition comprises a biocompatible polymer matrix having a
therapeutically effective amount of bisphosphonate incorporated
therein. Further, the invention relates to a method for the
sustained release in vivo of a bisphosphonate compound comprising
administering to a subject in need of treatment a therapeutically
effective amount of a sustained release composition comprising a
biocompatible polymer and a bisphosphonate compound.
[0018] In a particular embodiment, administration of the sustained
release composition comprising a biocompatible polymer and a
bisphosphonate can be to a joint, for example, the articular space
of a joint. For example, the sustained release composition can be
administered to the articular space of the knee, shoulder, ankle,
hip etc . . .
[0019] The sustained release composition of the invention
comprising a biocompatible polymer and a bisphosphonate compound
can be used for the treatment of diseases associated with bone
resorption or joint inflammation. For example, the sustained
release composition having a biocompatible polymer and a
bisphosphonate compound incorporated therein can be suitable for
use as a treatment for rheumatoid arthritis, osteoporosis or
Paget's disease.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The foregoing and other objects, features and advantages of
the invention will be apparent from the following more particular
description of preferred embodiments of the invention, as
illustrated in the accompanying drawings.
[0021] FIG. 1 is a plot of the serum EPO levels (mU/mL) versus time
in days post administration of the EPO-containing and
bisphosphonate-containing microparticles of the invention.
[0022] FIG. 2 is a plot of % hematocrit versus time in days post
administration of the EPO-containing and bisphosphonate-containing
microparticles of the invention.
[0023] FIG. 3 is a plot of the serum EPO levels (mU/mL) versus time
in days post administration of the EPO-containing and
alendronate-containing microparticles of the invention.
[0024] FIGS. 4A-4C are plots of % hematocrit versus time in days
post administration of the EPO-containing and
alendronate-containing microparticles of the invention.
[0025] FIG. 5 is a plot of the serum EPO levels (mU/mL) versus time
in days post administration of microparticles containing EPO and
pamidronate co-encapsulated (1% and 10% load).
[0026] FIG. 6 is a plot of % hematocrit versus time in days post
administration of microparticles containing EPO and pamidronate
co-encapsulated (1% and 10% load).
DETAILED DESCRIPTION OF THE INVENTION
[0027] A description of preferred embodiments of the invention
follows.
[0028] The present invention relates to a method for the sustained
release in vivo of a biologically active agent comprising
administering to a subject in need of treatment an effective amount
of a sustained release composition comprising a biocompatible
polymer having the biologically active agent incorporated therein,
and a bisphosphonate wherein the bisphosphonate is present in an
amount sufficient to modify the release profile of the biologically
active agent from the sustained release composition.
[0029] In one embodiment, the bisphosphonate compound can be
co-incorporated into the sustained release composition comprising
the biocompatible polymer and the biologically active agent
incorporated therein.
[0030] In another embodiment, the bisphosphonate compound can be
separately incorporated into a second biocompatible polymer. The
biocompatible polymer can be the same or different from the first
biocompatible polymer which has the biologically active agent
incorporated therein.
[0031] In yet another embodiment, the bisphosphonate compound can
be present in an unencapsulated state but comingled with the
sustained release composition. For example, the bisphosphonate can
be solubilized in the vehicle used to deliver the sustained release
composition. Alternatively, the bisphosphonate compound can be
present as a solid suspended in an appropriate vehicle. Further,
the bisphosphonate can be present as a powder which is comingled
with the sustained release composition.
[0032] Bisphosphonates are a group of synthetic pyrophosphates
characterized by a P--C--P type backbone. The bisphosphonates are
potent inhibitors of bone resorption and ectopic calcification. In
general the bisphosphonates can be represented by Formula I: 1
[0033] wherein,
[0034] R.sub.1 is independently, H, alkyl, aryl or heteroaryl;
[0035] X is H, --OR.sub.1 or halogen;
[0036] R.sub.2 is H, O, S, N, (CH.sub.2).sub.n, branched alkylene,
branched or straight alkenylene or alkynylene;
[0037] n is an integer from about 0 to about 18;
[0038] Y is H, R.sub.1, halogen, amino, cyano or amido group.
[0039] As used herein, "alkyl" refers to a straight chain or
branched, substituted or unsubstituted C.sub.1-C.sub.18 hydrocarbon
group. Examples of suitable alkyl groups include, but are not
limited to, methyl, ethyl, propyl, butyl, pentyl, isopropyl,
isobutyl, and tert-butyl. As used herein, "halogen" refers to
chlorine, bromine, iodine and fluorine. The term "aryl" as used
herein refers to unsubstituted and substituted aromatic
hydrocarbons. The term "heteroaryl" as used herein refers to
unsubstituted or substituted aryl groups wherein at least one
carbon of the aryl group is replaced with a heteroatom (e.g., N, O
or S). Suitable substituents, include, for example, but are not
limited to, halogen, --OH, alkoxy, amino, amido, --SH, cyano,
--NO.sub.2, --COOH, --COH, --COOR.sub.1.
[0040] A number of geminal bisphosphonates such as those shown
below are currently used for the treatment of moderate to severe
Paget's disease and hypercalcemia associated with malignant
neoplasms, treatment of osteolytic bone lesions associated with
multiple myeloma and treatment of osteoporosis. 2 3
[0041] Bisphosphonates suitable for use in the invention include
those described in U.S. Pat. No. 4,705,651, U.S. Pat. No.
4,327,039, U.S. Pat. No. 5,312,954 and U.S. Pat. No. 5,196,409 to
Breuer et al., U.S. Pat. No. 5,412,141 to Nugent, U.S. Pat. Nos.
4,922,007 and 5,019,651 to Kieczykowski et al., U.S. Pat. No.
5,583,122 to Benedict et al., U.S. Pat. No. 6,080,779 to Gasper et
al., U.S. Pat. No. 6,117,856 to Benderman et al., U.S. Pat. No.
6,162,929 to Foricher et al. and U.S. Pat. No. 5,885,473 to
Papapoulos et al. the entire content of all of which are hereby
incorporated by reference.
[0042] "Patient" as that term is used herein refers to the
recipient of the treatment. Mammalian and non-mammalian patients
are included. In a specific embodiment, the patient is a mammal,
such as a human, canine, murine, feline, bovine, ovine, swine or
caprine. In a preferred embodiment, the patient is a human.
[0043] The term "sustained release composition" as defined herein,
comprises a biocompatible polymer having incorporated therein at
least one biologically active agent. Suitable biocompatible
polymers, can be either biodegradable or non-biodegradable polymers
or blends or copolymers thereof, as described herein.
[0044] Typically, the sustained release composition can contain
from about 0.01% (w/w) to about 50% (w/w) of the biologically
active agent (dry weight of composition). The amount of agent used
will vary depending upon the desired effect of the agent, the
planned release levels, and the time span over which the agent will
be released. A preferred range of agent loading is between about
0.1% (w/w) to about 30% (w/w) agent. A more preferred range of
agent loading is between about 0.5% (w/w) to about 20% (w/w)
agent.
[0045] The sustained release compositions of this invention can be
formed into many shapes such as a film, a pellet, a rod, a
filament, a cylinder, a disc, a wafer or a microparticle. A
microparticle is preferred. A "microparticle" as defined herein,
comprises a polymer component having a diameter of less than about
one millimeter and having a biologically active agent dispersed
therein. A microparticle can have a spherical, non-spherical or
irregular shape. Typically, the microparticle will be of a size
suitable for injection. A preferred size range for microparticles
is from about one to about 180 microns in diameter.
[0046] As defined herein, a sustained release of biologically
active agent is a release of the agent from a sustained release
composition. The release occurs over a period which is longer than
that period during which a therapeutically significant amount of
the biologically active agent, would be available following direct
administration of a solution of the biologically active agent. It
is preferred that a sustained release be a release of biologically
active agent which occurs over a period of greater than two days. A
sustained release of biologically active agent, from a sustained
release composition can be a continuous or a discontinuous release,
with relatively constant or varying rates of release. The
continuity of release and level of release can be affected by the
type of polymer composition used (e.g., monomer ratios, molecular
weight, and varying combinations of polymers), agent loading,
and/or selection of excipients to produce the desired effect.
[0047] As used herein, the term "a" or "an" refers to one or
more.
[0048] As used herein, "sufficient bisphosphonate compound to
modify the release profile of the biologically active agent from
the biocompatible polymer" means that amount of bisphosphonate
compound which modifies the release profile of the biologically
active agent from the biocompatible polymer which occurs when the
sustained release composition does not include a bisphosphonate
compound.
[0049] "Modifies the release profile" as that term is used herein
refers to a prolongation of the period in which a therapeutic
amount of the biologically active agent is released from the
biocompatible polymer. It has also been observed that the initial
release of biologically active agent can be reduced when a
bisphosphonate is present in the sustained release composition.
[0050] A modification of the release profile can be confirmed by
appropriate pharmacokinetic monitoring of the patient's serum for
the presence of the biologically active agent or pharmacodynamic
monitoring of the patient to monitor the therapeutic effects of the
agent upon the patient. For example, specific antibody testing, as
is well known in the art, can be used to determine the
concentration of certain biologically active agents in the
patient's serum. An example of such testing is described herein for
erythropoietin. Further, the therapeutic effect of the biologically
active agent can be determined by monitoring the pharmocodynamic
effects of the biologically active agent. For example,
determination of the patient's hematocrit in response to
administration of erythropoeitin, as described herein. Methods of
monitoring pharmacodynamic effects can be selected based upon the
biologically active agent being administered using widely available
techniques.
[0051] As used herein, a "therapeutically effective amount",
"prophylactically effective amount" or "diagnostically effective
amount" is the amount of the sustained release composition needed
to elicit the desired biological response following
administration.
[0052] The polymers of the invention are biocompatible. Suitable
biocompatible polymers, can be either biodegradable or
non-biodegradable polymers or blends or copolymers thereof, as
described herein.
[0053] Suitable biocompatible polymers, can be either biodegradable
or non-biodegradable polymers or blends or copolymers thereof, as
described herein. A polymer is biocompatible if the polymer and any
degradation products of the polymer are non-toxic to the recipient
and also possess no significant deleterious or untoward effects on
the recipient's body, such as an immunological reaction at the
injection site.
[0054] "Biodegradable", as defined herein, means the composition
will degrade or erode in vivo to form smaller chemical species.
Degradation can result, for example, by enzymatic, chemical and
physical processes. Suitable biocompatible, biodegradable polymers
include, for example, poly(lactides), poly(glycolides),
poly(lactide-co-glycolides), poly(lactic acid)s, poly(glycolic
acid)s, polycarbonates, polyesteramides, polyanydrides, poly(amino
acids), polyorthoesters, poly(dioxanone)s, poly(alkylene
alkylate)s, copolymers or polyethylene glycol and polyorthoester,
biodegradable polyurethane, blends thereof, and copolymers
thereof.
[0055] Suitable biocompatible, non-biodegradable polymers include
non-biodegradable polymers selected from the group consisting of
polyacrylates, polymers of ethylene-vinyl acetates and other acyl
substituted cellulose acetates, non-degradable polyurethanes,
polystyrenes, polyvinylchloride, polyvinyl flouride, poly(vinyl
imidazole), chlorosulphonate polyolefins, polyethylene oxide,
blends thereof, and copolymers thereof.
[0056] Acceptable molecular weights for polymers used in this
invention can be determined by a person of ordinary skill in the
art taking into consideration factors such as the desired polymer
degradation rate, physical properties such as mechanical strength,
and rate of dissolution of polymer in solvent. Typically, an
acceptable range of molecular weight is of about 2,000 Daltons to
about 2,000,000 Daltons.
[0057] In a particular embodiment, the polymer is biodegradable
polymer or copolymer. In a more preferred embodiment, the polymer
is a poly(lactide-co-glycolide)(hereinafter "PLG"). The PLG can
have a lactide:glycolide ratio, for example, of about 10:90, 25:75,
50:50, 75:25 or 90:10 and a molecular weight of about 5,000 Daltons
to about 70,000 Daltons.
[0058] The term "biologically active agent," as used herein, is an
agent, or its pharmaceutically acceptable salt, which when released
in vivo, possesses the desired biological activity, for example
therapeutic, diagnostic and/or prophylactic properties in vivo. It
is understood that the term includes stabilized biologically active
agents as described herein.
[0059] Examples of suitable biologically active agents include
proteins such as immunoglobulins, antibodies, cytokines (e.g.,
lymphokines, monokines, chemokines), interleukins, interferons,
erythropoietin, nucleases, tumor necrosis factor, colony
stimulating factors, insulin, enzymes (e.g. superoxide dismutase,
plasminogen activator, etc.), tumor suppressors, blood proteins,
hormones and hormone analogs (e.g., growth hormone,
adrenocorticotropic hormone, and luteinizing hormone releasing
hormone (LHRLH)), Vaccines (e.g., tumoral, bacterial and viral
antigens), antigens, blood coagulation factors; growth factors;
peptides such as protein inhibitors, protein antagonists, and
protein agonists; nucleic acids, such as antisense molecules;
oligonucleotides; and ribozymes. Small molecular weight agents
suitable for use in the invention include, antitumor agents such as
bleomycin hydrochloride, carboplatin, methotrexate and adriamycin;
antibiotics such as gentamicin, tetracycline hydrochloride and
ampicillin; antipyretic, analgesic and anti-inflammatory agents;
antitussives and expectorants such as ephedrine hydrochloride,
methylephedrine hydrochloride, noscapine hydrochloride and codeine
phosphate; sedatives such as chlorpromazine hydrochloride,
prochlorperazine hydrochloride and atropine sulfate; muscle
relaxants such as tubocurarine chloride; antiepileptics such as
sodium phenytoin and ethosuximide; antiulcer agents such as
metoclopramide; antidepressants such as clomipramine; antiallergic
agents such as diphenhydramine; cardiotonics such as theophillol;
antiarrhythmic agents such as propranolol hydrochloride;
vasodilators such as diltiazem hydrochloride and bamethan sulfate;
hypotensive diuretics such as pentolinium and ecarazine
hydrochloride; antidiuretic agents such as metformin;
anticoagulants such as sodium citrate and sodium heparin;
hemostatic agents such as thrombin, menadione sodium bisulfite and
acetomenaphthone; antituberculous agents such as isoniazide and
ethanbutol; hormones such as prednisolone sodium phosphate and
methimazole; antipsychotic agents such as risperidone; and narcotic
antagonists such as nalorphine hydrochloride.
[0060] In one embodiment, the biologically active agent is
stabilized. The biologically active agent can be stabilized against
degradation, loss of potency and/or loss of biological activity,
all of which can occur during formation of the sustained release
composition having the biologically active agent dispersed therein,
and/or prior to and during in vivo release of the biologically
active agent. In one embodiment, stabilization can result in a
decrease in the solubility of the biologically active agent, the
consequence of which is a reduction in the initial release of
biologically active agent, in particular, when release is from a
sustained release composition. In addition, the period of release
of the biologically active agent can be prolonged.
[0061] Stabilization of the biologically active agent can be
accomplished, for example, by the use of a stabilizing agent or a
specific combination of stabilizing agents. The stabilizing agent
can be present in the mixture. "Stabilizing agent", as that term is
used herein, is any agent which binds or interacts in a covalent or
non-covalent manner or is included with the biologically active
agent. Stabilizing agents suitable for use in the invention are
described in U.S. Pat. Nos. 5,716,644, 5,674,534, 5,654,010,
5,667,808, and 5,711,968, 6,265,389 and 6,514,533 the entire
teachings of which are incorporated herein by reference.
[0062] For example, a metal cation can be complexed with the
biologically active agent, or the biologically active agent can be
complexed with a polycationic complexing agent such as protamine,
albumin, spermidine and spermine, or associated with a
"salting-out" salt. In addition, a specific combination of
stabilizing agents and/or excipients may be needed to optimize
stabilization of the biologically active agent.
[0063] Suitable metal cations include any metal cation capable of
complexing with the biologically active agent. A metal
cation-stabilized biologically active agent, as defined herein,
comprises a biologically active agent and at least one type of
metal cation wherein the cation is not significantly oxidizing to
the biologically active agent. In a particular embodiment, the
metal cation is multivalent, for example, having a valency of +2 or
more. It is preferred that the metal cation be complexed to the
biologically active agent.
[0064] Suitable stabilizing metal cations include biocompatible
metal cations. A metal cation is biocompatible if the cation is
non-toxic to the recipient, in the quantities used, and also
presents no significant deleterious or untoward effects on the
recipient's body, such as a significant immunological reaction at
the injection site. The suitability of metal cations for
stabilizing biologically active agents and the ratio of metal
cation to biologically active agent needed can be determined by one
of ordinary skill in the art by performing a variety of stability
indicating techniques such as polyacrylamide gel electrophoresis,
isoelectric focusing, reverse phase chromatography, and HPLC
analysis on particles of metal cation-stabilized biologically
active agents prior to and following particle size reduction and/or
encapsulation. The molar ratio of metal cation to biologically
active agent is typically between about 1:2 and about 100:1,
preferably between about 2:1 and about 12:1.
[0065] Examples of stabilizing metal cations include, but are not
limited to, K.sup.+, Zn.sup.+2, Mg.sup.+2 and Ca.sup.+2.
Stabilizing metal cations also include cations of transition
metals, such as Cu.sup.+2. Combinations of metal cations can also
be employed.
[0066] The biologically active agent can also be stabilized with at
least one polycationic complexing agent. Suitable polycationic
complexing agents include, but are not limited to, protamine,
spermine, spermidine and albumin. The suitability of polycationic
complexing agents for stabilizing biologically active agents can be
determined by one of ordinary skill in the art in the manner
described above for stabilization with a metal cation. An equal
weight ratio of polycationic complexing agent to biologically
active agent is suitable.
[0067] Further, excipients can be added to maintain the potency of
the biologically active agent over the duration of release and
modify polymer degradation. The excipients can be added to the
dispersed system which is then atomized or can be added to the
mixture which is subjected to fragmenting either before or after
fragmentation of the dried substance to achieve particles of
biologically active agent. Suitable excipients include, for
example, carbohydrates, amino acids, fatty acids, surfactants, and
bulking agents, and are known to those skilled in the art. An
acidic or a basic excipient is also suitable. The amount of
excipient used is based on ratio to the biologically active agent,
on a weight basis. For amino acids, fatty acids and carbohydrates,
such as sucrose, trehalose, lactose, mannitol, dextran and heparin,
the ratio of carbohydrate to biologically active agent, is
typically between about 1:10 and about 20:1. For surfactants the
ratio of surfactant to biologically active agent is typically
between about 1:1000 and about 2:1. Bulking agents typically
comprise inert materials. Suitable bulking agents are known to
those skilled in the art.
[0068] The excipient can also be a metal cation component which is
separately dispersed within the polymer matrix. This metal cation
component acts to modulate the release of the biologically active
agent and is not complexed with the biologically active agent. The
metal cation component can optionally contain the same species of
metal cation, as is contained in the metal cation stabilized
biologically active agent, if present, and/or can contain one or
more different species of metal cation. The metal cation component
acts to modulate the release of the biologically active agent from
the polymer matrix of the sustained release composition and can
enhance the stability of the biologically active agent in the
composition. A metal cation component used in modulating release
typically comprises at least one type of multivalent metal cation.
Examples of metal cation components suitable to modulate release
include or contain, for example, Mg(OH).sub.2, MgCO.sub.3 (such as
4MgCO.sub.3.Mg(OH).sub.2.5H.sub.2O), MgSO.sub.4, Zn(OAc).sub.2,
Mg(OAc).sub.2, ZnCO.sub.3 (such as
3Zn(OH).sub.2.2ZnCO.sub.3)ZnSO.sub.4, ZnCl.sub.2, MgCl.sub.2,
CaCO.sub.3, Zn.sub.3(C.sub.6H.sub.5O.sub.7).sub.2 and
Mg.sub.3(C.sub.6H.sub.5O.sub.7).sub.2. A suitable ratio of metal
cation component is between about 1:99 to about 1:2 by weight. The
optimum ratio depends upon the polymer and the metal cation
component utilized. A polymer matrix containing a dispersed metal
cation component to modulate the release of a biologically active
agent from the polymer matrix is further described in U.S. Pat. No.
5,656,297 to Bernstein et al. and co-pending U.S. patent
application Ser. No. 09/056,566 filed on Apr. 7, 1998, the
teachings of both of which are incorporated herein by reference in
their entirety.
[0069] The invention described herein also relates to
pharmaceutical compositions suitable for use in the invention. In
one embodiment, the pharmaceutical composition comprises a
sustained release composition comprising a biocompatible polymer
having an effective amount of a biologically active agent
incorporated therein, and an amount of bisphosphonate compound
sufficient to modify the release profile of the biologically active
agent from the sustained release composition.
[0070] In one embodiment, the bisphosphonate compound can be
co-incorporated into the sustained release composition comprising
the biocompatible polymer and the biologically active agent
incorporated therein.
[0071] In another embodiment, the pharmaceutical composition
comprises the sustained release composition comprising a first
biocompatible polymer having incorporated therein an effective
amount of a biologically active agent and a second biocompatible
polymer having incorporated therein an amount of bisphosphonate
which modifies the release profile of the biologically active agent
from the first polymer. In a particular embodiment, the first and
second polymers are the same type of polymer. In another
embodiment, the first and second polymers are different.
[0072] In yet another embodiment, the bisphosphonate compound can
be present in the pharmaceutical composition in an unencapsulated
state. For example, the bisphosphonate compound can be comingled
with the sustained release composition. In one embodiment, the
bisphosphonate can be solubilized in the vehicle used to deliver
the pharmaceutical composition. Alternatively, the bisphosphonate
compound can be present as a solid suspended in an appropriate
vehicle useful for delivering the pharmaceutical composition.
Further, the bisphosphonate can be present as a powder which is
comingled with the sustained release composition.
[0073] The present invention also relates to a composition for the
sustained release of bisphosphonates. The sustained release
composition comprises a biocompatible polymer matrix having a
therapeutically effective amount of bisphosphonate incorporated
therein. Further, the invention relates to a method for the
sustained release in vivo of a bisphosphonate compound comprising
administering to a subject in need of treatment a therapeutically
effective amount of a sustained release composition comprising a
biocompatible polymer and a bisphosponate compound.
[0074] In a particular embodiment, administration of the sustained
release composition comprising a biocompatible polymer and a
bisphosphonate can be to a joint, for example, the articular space
of a joint. For example, the sustained release composition can be
administered to the articular space of the knee, shoulder, ankle,
hip etc . . .
[0075] The sustained release composition of the invention
comprising a biocompatible polymer and a bisphosphonate compound
can be used for the treatment of diseases associated with bone
resorption or joint inflammation. For example, the sustained
release composition having a biocompatible polymer and a
bisphosphonate compound incorporated therein can be suitable for
use as a treatment for rheumatoid arthritis, osteoporosis or
Paget's disease.
[0076] A number of methods are known by which sustained release
compositions (polymer/active agent matrices) can be formed. In many
of these processes, the material to be encapsulated is dispersed in
a solvent containing a wall forming material. At a single stage of
the process, solvent is removed from the microparticles and
thereafter the microparticle product is obtained.
[0077] Methods for forming a composition for the sustained release
of biologically active agent are described in U.S. Pat. No.
5,019,400, issued to Gombotz et al., and issued U.S. Pat. No.
5,922,253 issued to Herbert et al. the teachings of which are
incorporated herein by reference in their entirety.
[0078] In this method, a mixture comprising a biologically active
agent, a biocompatible polymer and a polymer solvent is processed
to create droplets, wherein at least a significant portion of the
droplets contains polymer, polymer solvent and the active. These
droplets are then frozen by a suitable means. Examples of means for
processing the mixture to form droplets include directing the
dispersion through an ultrasonic nozzle, pressure nozzle, Rayleigh
jet, or by other known means for creating droplets from a
solution.
[0079] Means suitable for freezing droplets include directing the
droplets into or near a liquified gas, such as liquid argon or
liquid nitrogen to form frozen microdroplets which are then
separated from the liquid gas. The frozen microdroplets are then
exposed to a liquid or solid non-solvent, such as ethanol, hexane,
ethanol mixed with hexane, heptane, ethanol mixed with heptane,
pentane or oil.
[0080] The solvent in the frozen microdroplets is extracted as a
solid and/or liquid into the non-solvent to form a polymer/active
agent matrix comprising a biocompatible polymer and a biologically
active agent. Mixing ethanol with other non-solvents, such as
hexane, heptane or pentane, can increase the rate of solvent
extraction, above that achieved by ethanol alone, from certain
polymers, such as poly(lactide-co-glycolid- e) polymers.
[0081] A wide range of sizes of sustained release compositions can
be made by varying the droplet size, for example, by changing the
ultrasonic nozzle diameter. If the sustained release composition is
in the form of microparticles, and very large microparticles are
desired, the microparticles can be extruded, for example, through a
syringe directly into the cold liquid. Increasing the viscosity of
the polymer solution can also increase microparticle size. The size
of the microparticles which can be produced by this process ranges,
for example, from greater than about 1000 to about 1 micrometers in
diameter.
[0082] Yet another method of forming a sustained release
composition, from a suspension comprising a biocompatible polymer
and a biologically active agent, includes film casting, such as in
a mold, to form a film or a shape. For instance, after putting the
suspension into a mold, the polymer solvent is then removed by
means known in the art, or the temperature of the polymer
suspension is reduced, until a film or shape, with a consistent dry
weight, is obtained.
[0083] A further example of a conventional microencapsulation
process and microparticles produced thereby is disclosed in U.S.
Pat. No. 3,737,337, incorporated by reference herein in its
entirety, wherein a solution of a wall or shell forming polymeric
material in a solvent is prepared. The solvent is only partially
miscible in water. A solid or core material is dissolved or
dispersed in the polymer-containing mixture and, thereafter, the
core material-containing mixture is dispersed in an aqueous liquid
that is immiscible in the organic solvent in order to remove
solvent from the microparticles.
[0084] Another example of a process in which solvent is removed
from microparticles containing a substance is disclosed in U.S.
Pat. No. 3,523,906, incorporated herein by reference in its
entirety. In this process a material to be encapsulated is
emulsified in a solution of a polymeric material in a solvent that
is immiscible in water and then the emulsion is emulsified in an
aqueous solution containing a hydrophilic colloid. Solvent removal
from the microparticles is then accomplished by evaporation and the
product is obtained.
[0085] In still another process as shown in U.S. Pat. No.3,691,090,
incorporated herein by reference in its entirety, organic solvent
is evaporated from a dispersion of microparticles in an aqueous
medium, preferably under reduced pressure.
[0086] Similarly, the disclosure of U.S. Pat. No. 3,891,570,
incorporated herein by reference in its entirety, shows a method in
which solvent from a dispersion of microparticles in a polyhydric
alcohol medium is evaporated from the microparticles by the
application of heat or by subjecting the microparticles to reduced
pressure.
[0087] Another example of a solvent removal process is shown in
U.S. Pat. No. 3,960,757, incorporated herein by reference in its
entirety.
[0088] Tice et al., in U.S. Pat. No. 4,389,330, describe the
preparation of microparticles containing an active agent by a
method comprising: (a) dissolving or dispersing an active agent in
a solvent and dissolving a wall forming material in that solvent;
(b) dispersing the solvent containing the active agent and wall
forming material in a continuous-phase processing medium; (c)
evaporating a portion of the solvent from the dispersion of step
(b), thereby forming microparticles containing the active agent in
the suspension; and (d) extracting the remainder of the solvent
from the microparticles.
[0089] Without being bound by a particular theory it is believed
that the release of the biologically active agent can occur by two
different mechanisms. First, the biologically active agent can be
released by diffusion through aqueous filled channels generated in
the polymer matrix, such as by the dissolution of the biologically
active agent, or by voids created by the removal of the polymer
solvent during the preparation of the sustained release
composition. A second mechanism is the release of the biologically
active agent, due to degradation of the polymer. The rate of
degradation can be controlled by changing polymer properties that
influence the rate of hydration of the polymer. These properties
include, for instance, the ratio of different monomers, such as
lactide and glycolide, comprising a polymer; the use of the
L-isomer of a monomer instead of a racemic mixture; and the
molecular weight of the polymer. These properties can affect
hydrophilicity and crystallinity, which control the rate of
hydration of the polymer.
[0090] By altering the properties of the polymer, the contributions
of diffusion and/or polymer degradation to biologically active
agent release can be controlled. For example, increasing the
glycolide content of a poly(lactide-co-glycolide) polymer and
decreasing the molecular weight of the polymer can enhance the
hydrolysis of the polymer and thus, provides an increased
biologically active agent release from polymer erosion.
[0091] The composition of this invention can be administered in
vivo, for example, to a human, or to an animal, orally, or
parenterally such as by injection, implantation (e.g.,
subcutaneously, intramuscularly, intraperitoneally, intracranially,
and intradermally), administration to mucosal membranes (e.g.,
intranasally, intravaginally, intrapulmonary, buccally or by means
of a suppository), or in situ delivery (e.g., by enema or aerosol
spray) to provide the desired dosage of antigen or labile agent
based on the known parameters for treatment with the particular
agent of the various medical conditions.
[0092] While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
scope of the invention encompassed by the appended claims.
[0093] Exemplifications
[0094] Materials and Methods
[0095] In Vivo Testing
[0096] Male Sprague-Dawley Rats, weighing between 350 to 450 grams
(Charles River Laboratories, Inc.) were used in the studies
described below following acclimation in standard animal housing
for at least seven days. Animals were treated with cyclosporin
(Sandimmune, Sandoz; CS) 5 mg/kg ip daily for days 0-14 post
administration of the sustained release composition and
bisphosphonate, and then 3 times per week thereafter. In some
instances, cyclosporin treatment was omitted for at least two
non-consecutive days during the initial 0-14 day treatment.
Administration of the EPO-containing microparticles and
bisphosphonate compound is described in detail below.
[0097] Preparation of EPO-Containing Microparticles
[0098] Microparticles containing recombinant human Erythropoietin
(EPO) were made following the procedure described in U.S. Pat. No.
5,716,644 issued on Feb. 10, 1998 to Zale et al., the entire
content of which is hereby incorporated by reference. Specifically,
the EPO-containing microparticles were prepared using a polymer
purchased from Alkermes, Inc. of Cincinnati, Ohio having Cat
No.5050DL2A which is a poly(lactide-co-glycolide) 10 kD polymer
having a lactide/glycolide ratio of 50:50. The
biosphosphonate-containing microparticles were prepared using a
poly(lactide-co-glycolide) 25 kD polymer having a lactide/glycolide
ratio of 50:50 also available from Alkermes, Inc. of Cincinnati,
Ohio and having Cat. No. 5050DL3A. The EPO was obtained from
Johnson & Johnson, New Brunswick, N.J. and stabilized prior to
encapsulation as described in U.S. Pat. No. 5,716,644 using an EPO
loading of about 1.6% w/w of the total weight of stabilized EPO in
the microparticles.
[0099] Preparation of Bisphosphonate-Containing Microparticles
[0100] Bisphosphonate-containing microparticles having both a 1%
and 2.5% w/w of the final weight of the microparticle theoretical
load of the indicated bisphosphonate were prepared using a
poly(lactide-co-glycolide) Cat. No. 5050DL3 earlier described
having a lactide:glycolide ratio of 50:50.
[0101] Briefly, the bisphosphonates are soluble in water and
insoluble in organics, making phase separation a suitable method
for use in preparing the bisphosphonate-containing microparticles.
First 212 mg of the poly(D,L-lactide-co-glycolide), with a
molecular weight of about 25 kD available from Alkermes, Inc. of
Cincinnati, Ohio, as Cat. No. 5050DL3A was weighed out and
dissolved in methylene chloride at a concentration of about 5.9%
W/V. 90 mg pamidronate disodium in 375 mg mannitol (available as
AREDIA 90.RTM.) was weighed out and dissolved in about 3 g water.
The encapsulate solution was then added to the polymer solution,
and probe sonicated using pulses for about 1 minute to generate an
extremely fine water-in-oil (W/O) emulsion.
[0102] The resulting emulsion was charged to a 350 mL glass
reactor. The stir speed was set to about 1000 RPM. The coacervation
agent, Dow Corning 360 Fluid, 350 cs, was slowly added by
peristaltic pump to the stirring W/O emulsion to induce phase
separation. Dow Corning 360 Fluid addition was halted when a 1:1
ratio of fluid to methylene chloride ratio had been achieved. Then
the bottom stopcock of the reactor was opened in order to gravity
feed embryonic microparticles into a heptane quench. After stirring
for about 2 hours in the heptane quench, the hardened
microparticles were isolated by filtration and allowed to dry in an
ambient temperature vacuum chamber overnight. The product was then
collected and weighed.
EXAMPLE 1
[0103] Pharamacological Effects of Bisphosphonate-Containing
Microparticles on EPO Release from EPO-Containing Micro Following
Co-Administration
[0104] The Phamacokinetic (PK)/Pharmacodynamic (PD) response to EPO
released from EPO-containing microparticles when co-administered
with bisphosphonate-containing microparticles in vivo to male
Sprague-Dawley rats was determined.
[0105] Microparticle Administration
[0106] Animals were anesthetized with 5% halothane. Each animal was
shaved and the back swabbed with alcohol. Microparticles were
resuspended using 0.75 mL vehicle (3% carboxymethylcellulose, 0.1%
Tween 20, 0.9% NaCl, pH .about.6). The microparticles were injected
into an interscapular site using a 21 guage thinwall needle
attached to a 1 mL syringe. Animals were dosed to receive a total
of 10,000 U EPO in combination with a total of 2.5 mg of the
indicated bisphosphonate. The amount of bisphosphonate-containing
microparticles needed was determined based on the theoretical load
of bisphosphonate in the microparticle formulation. For example,
100 mg of bisphosphonate-containing microparticles have a 2.5%
theoretical load of bisphosphonate resulted in administration of 25
mg. Animals were followed for 47 days post implantation, except for
Group G (Alendronate), which was followed for 57 days. The
microparticles mixed and administered as one injection.
[0107] Bisphosphonate-containing microparticles having a 2.5%
theoretical load of bisphosphonate were prepared as described above
with a 2.5% theoretical load using the following bisphosphonate
comounds: pamidronate (AREDIA.RTM.,
(3-amino-1-hydroxypropylidene)bispnosphonic acid) disodium salt),
etidronate ((1-hydroxyethyledene)bisphophonic acid) disodium salt,
DIDRONEL.RTM.k), tiludronate
([[(4-chlorophenyl)thio]methylene]bisphospho- nic acid disodium
salt, SKELID.RTM.), risedronate ([1-hydroxy-2-(3-pyridin-
yl)ethylidene]bisphosphonic acid) monosodium salt, ACTONEL.RTM.),
and alendronate ((4-amino-1-hydroxybutylidene)bisphosphonic acid)
monosodium salt, FOSAMAX.RTM.). In addition, microparticles having
no bisphosphonate compound incorporated therein (placebo) were
prepared following the method outlined.
[0108] Sample Collection Timepoints (days) pre-bleed,
1,2,5,8,12,15,19,22, 26,29,33,36,40,42,47,50,54, & 57
1TABLE 1 EPO Biphosphonate # of Animal Dose Biphosphonate Dose
Group per Group (Units) Compound (mg) A 4 10,000 -- -- B 4 10,000
Placebo Microparticles -- C 4 10,000 Pamidronate 2.5 mg (AREDIA
.RTM.) D 4 10,000 Etidronate (DIDRO- 2.5 mg NEL .RTM.) E 4 10,000
Tiludronate 2.5 mg (SKELID .RTM.) F 4 10,000 Risedronate 2.5 mg
(ACTONEL .RTM.) G 4 10,000 Alendronate 2.5 mg (FOSAMAX .RTM.)
[0109] Serum Evaluation
[0110] Serum samples (40 .mu.L) were collected via tail vein on the
following days relative to microparticle administration: pre-bleed,
1, 2, 5, 8, 12, 15, 19, 22, 26, 29, 33, 36, 40, 42, 47, 50, 54 and
57. After clotting, the samples were centrifuged and frozen at
-70.degree. C. Serum EPO levels were quantitated by ELISA (R&D
Systems, Minneapolis, Minn. Cat. No. DEPOO). The results are
presented graphically in FIG. 1.
[0111] Hematocrits were evaluated manually following centrifugation
for 5 minutes at 8000 rpm (on four animals per group) using a
capillary tube. Hematocrits were also determined at the following
intervals relative to microparticle administration: pre-bleed, 1,
2, 5, 8, 12, 15, 19, 22, 26, 29, 33, 36, 40, 42, 47, 50, 54 and 57.
The results are presented graphically in FIG. 2.
[0112] Animals were observed on a regular basis for any signs of
abnormal behavior. Injection sites were observed on a regular basis
for induration, weeping or erythema. Sites were observed on a
weekly basis for blanching. Body weights were taken and recorded at
each sample collection timepoint.
[0113] The experiment was terminated once EPO serum levels had
fallen below the limit of quantitation.
[0114] Results
[0115] The dose normalized data from ELISA testing of serum EPO
levels are shown in FIG. 1. The data show that each of the
bisphosphonate compounds tested enhanced the release of EPO from
EPO-containing microparticles in comparison to the group receiving
only EPO-containing microparticles. However, alendronate alone was
shown to significantly affect the duration of EPO release from
EPO-containing microparticles in comparison to groups receiving
placebo microparticles co-administered with EPO-containing
microparticles. That is, the animals of Group G had measurable
levels of serum EPO at day 29 (23.17.+-.8.22). This was significant
in comparison to the placebo treated controls which were below the
limit of quantitation at p<0.01. Further, a significant
reduction in burst was seen in the Group C animals (Cmax:
2072.73.+-.437.8) when compared to Group B animals (Cmax:
3989.56.+-.883.47, p<0.05). Although the pamidronate treatment
(Group C), increased the duration of release of detectable levels
of EPO, it was not significantly different from the placebo-treated
group (group B).
[0116] Hematocrits in 4 out of 5 of the treated groups rose above
that of the control groups A and B. Further, it was observed for
Group G (alendronate) that the hematocrits remained significantly
higher than controls past day 36 (FIG. 2). Day 36 is the last day
serum levels of EPO were positive. The Alendronate treated group
demonstrated higher hematocrits out to Day 47 which is the last day
measured for control Groups A and B, demonstrating that the
pharmacodynamic (PD) response extended out beyond pharmacokinetic
(PK) response. In addition, at timepoints 26, 33 and 36 days, the
hematocrits in the the Group C animals (pamidronate treated) were
also significantly higher than controls (p<0.05). Following day
26, the hematocrits of all groups, with the exception of Group G,
had reached baseline or near baseline levels. That is, Group G had
significantly higher hematocrits than controls at all time points
between day 26 and 47 (p<0.05) and did not approach baseline
until day 57. Finally, comparing 60% hematocrits, the alendronate
extended the PD response to EPO from day 32 in the placebo control
group (B) to day 49. This is a 17-day enhancement using
alendronate.
[0117] Pamidronate disodium (AREDIA.RTM.) in mannitol was dosed at
1 mg and admixed with EPO-containing microparticles.
[0118] In the group that received pamidronate in the vehicle (Group
E) there was also an increase in duration of release. Group E also
showed a significant elevation of release in the day 12 to day 15
timepoints relative to other groups. This enhanced release can be
useful in clinical settings where tailored release is desired.
[0119] The use of pamidronate in vehicle (group E) also enhanced
EPO PK/PD
EXAMPLE 2
[0120] Co-Administration of EPO-Containing Microparticles with
Alendronate-Containing Microparticles at Varying Doses
[0121] This example compares the PK/PD response to EPO released
from EPO-containing microparticles when co-administered with
various doses of alendronate-containing microparticles.
[0122] Materials and Methods
[0123] EPO-containing microparticles, alendronate-containing
microparticles and placebo microparticles were prepared as
described in Example 1. Alendronate-containing microparticles were
prepared at a loading of 1.0% and 2.5% (theoretical). Microparticle
administration, sample collection and sample analysis were as
described in Example 1 and are summarized in Table 2. Sample
collection timepoints were pre-bleed, 1, 2, 5, 8, 12, 15, 19, 22,
26, 29, 33, 36, 40.
2TABLE 2 Number of Alendronate Animals Dose (mg) per Epo Dose
(theoretical load .times. mg Placebo Dose Group Group (U) .mu.
particles = dose) (mg) I 4 10,000 U -- 100 mg II 4 10,000 U -- 50
mg III 4 10,000 U -- 25 mg IV 4 -- 2.5 mg -- (2.5% .times. 100 mg
.mu. particles) V 4 10,000 U 2.5 mg -- (2.5% .times. 100 mg .mu.
particles) VI 4 10,000 U 1.25 mg -- (2.5% .times. 50 mg .mu.
particles) VII 4 10,000 U 0.625 mg -- (2.5% .times. 25 mg .mu.
particles) VIII 4 10,000 U 1.0 mg -- (1.0% .times. 100 mg .mu.
particles) IX 4 10,000 U 0.5 mg -- (1.0% .times. 50 mg .mu.
particles) X 4 10,000 U 0.25 mg -- (1.0% .times. 25 mg .mu.
particles)
[0124] Results:
[0125] Serum ELISA data show a clear dose response in animals that
received the 1% and 2.5% alendronate encapsulated microspheres.
FIG. 3 shows the pharmacokinetic profile over the study period out
to 36 days. Serum EPO levels in animals of Groups I, II and III,
receiving only EPO-containing microparticles and placebo
microparticles (no bisphosphonate) at 100, 50 and 25 mg doses were
not measurable after day 22. Groups VIII, IX and X which received
1% alendronate-containing microparticles with a total dose of 1.0,
0.5 and 0.25 mg declined by day 29. However, serum EPO levels in
Groups V, VI and VII which received 2.5% loaded
alendronate-containing microparticles for a total of 2.5, 1.25 and
0.625 mg of alendronate were detectable out to at least day 34.
[0126] Table 3 summarizes Cmax data for this study. The Cmax for
Groups V and VI receiving 100 or 50 mg of the 2.5% loaded
alendronate-containing microparticles for a total of 2.5 and 1.25
mg, respectively were significantly lower than the dose matched
placebo Groups I and II (p<0.05). Cmax was not significantly
suppressed for Group VII compared to the corresponding placebo
control. Steady state levels (Day 5 to Day 29) for Groups VI and
VII were increased from 48 to 132 and 56 to 146 relative to their
controls (p<0.05). Groups VIII, IX and X (1% loaded
microparticles) showed steady state serum EPO increases of 48 to 84
and 56 to 111 at the 25 and 50 mg doses, however these differences
were not statistically significant compared to the placebo groups
at the same doses of blank microparticles.
3TABLE 3 Group Cmax Tmax Ave Steady State 100 mg I EPO + 100 mg
Placebo 3764.79 .+-. 425.06 1 81.17 .+-. 17.19 V EPO + 100 mg 2.5%
Alendronate 2003.31 .+-. 308.80 1 116.17 .+-. 24.18 VIII EPO + 100
mg 1.0% Alendronate 2966.20 .+-. 530.14 1 103.60 .+-. 7.47 50 mg II
EPO + 50 mg Placebo 2968.51 .+-. 260.47 1 48.27 .+-. 14.83 VI EPO +
50 mg 2.5% Alendronate 2538.13 .+-. 231.93 1 132.41 .+-. 24.90 IX
EPO + 50 mg 1.0% Alendronate 2464.98 .+-. 647.79 1 84.96 .+-. 35.89
25 mg III EPO + 25 mg Placebo 3597.26 .+-. 247.76 1 56.48 .+-.
10.09 VII EPO + 25 mg 2.5% Alendronate 2972.05 .+-. 823.56 1 146.92
.+-. 36.33 X EPO + 25 mg 1.0% Alendronate 3452.95 .+-. 1132.84 1
111.79 .+-. 54.93
[0127] FIG. 4A shows an enhanced hematocrit response in rats to all
three groups receiving varying doses of the 2.5% alendronate
containing-microparticles co-administered with EPO
containing-microparticles (Groups V, VI and VII) when compared to
groups receiving the corresponding placebo dose of microparticles
(FIG. 4C). The duration of hematocrits >60% was increased by at
least 6 days in all groups. The complete enhancement effect on the
pharmacodynamics could not be determined as a result of termination
of the study at day 40.
[0128] The hematocrit levels for Groups V, VI and VII (FIG. 4A)
were over 65% at day 40, significantly higher than controls (56%,
P<0.01). FIG. 4B shows the hematocrit levels of the Groups VIII,
IX and X treated with 100 mg, 50 mg or 25 mg of the 1%
alendronate-containing microparticles, respectively co-administered
with EPO containing-microparticles. Amongst Groups VIII, IX and X,
only the 100 mg dose (Group VIII) was significantly higher at day
40 than the hematocrit value of the group receiving 100 mg of
placebo microparticles co-administered with EPO-containing
microparticles.
[0129] FIG. 4C represents hematocrit values obtained following
injection with placebo microparticless co-administered with
EPO-containing microparticles. It noted from FIGS. 4A-4C that there
were no significant differences between hematocrits of the Groups
receiving varying doses of 2.5% loaded alendronate-containing
microparticles, receiving varying doses of 1.0% loaded
alendronate-containing microparticles and varying doses of placebo
microparticles when co-administered with EPO-containing
microparticles.
[0130] Groups IV, V and VI (co-administration of 2.5% loaded
alendronate-containing microparticles) as well as Group VIII (100
mg dose of the 1% alendronate-containing microparticles) had
palpable masses at the injection sites at day 40. The study was
terminated at this time to allow recovery of injection sites. There
were no raised/inflammed sites in the placebo groups, however,
which indicates that the inflammation was limited to the
alendronate groups. Where there was a lower dose of microparticles,
the size of the swelling was also smaller, and in the two lowest
doses of alendronate (1% load, 50 and 25 mg doses) there were no
palpable masses through the skin. Inflammation seen with
alendronate groups is likely due to an acute phase response that
can occur with amine containing bisphosphonates.
EXAMPLE 3
[0131] Effects of Pamidronate Co-Encapsulated with EPO Materials
and Methods
[0132] EPO-containing microparticles were prepared as described in
Example 1 using a 40 kD Polymer poly(lactide-co-glycolide) polymer
having a lactide glycolide ratio of 50:50 (Cat. No. 5050DL4A,
Alkermes, Inc., Cinncinnati, Ohio). In addition, EPO-containing
microparticles (1.9% theoretical load) having pamidronate
co-encapsulated at nominal loads of 1% and 10% (theoretical) were
also prepared as described in Example 1 for EPO alone.
[0133] Microparticle administration, sample collection and analysis
were as described in Example 1 and are summarized in Table 4.
Sample collection timepoints were pre-bleed, 1, 2, 6, 9, 13, 16,
20, 23, 27, 30, 34, 37, 41, 44, 48 days.
4 TABLE 4 # Animals per Amount of Pamidronate Group Group EPO (%
Theoretical Load) X 5* 20,000 U -- Y 5 20,000 U 1% Z 5 20,000 U 10%
*Routine bleeds are taken from 5 of the animals in each group. Two
animals from each group will be used for a histological assessment
of the injection sites at the day 23 timepoint.
[0134] Results:
[0135] Following an initial peak at nearly 10,000 mU/mL or above,
serum EPO levels in all groups decreased sharply until day 6, when
a steady-state was reached at approximately 100 mU/ml (FIG. 5).
However, serum EPO levels in groups which had been treated with
EPO-containing microparticles co-encapsulated with 1% pamidronate
began to decrease more rapidly such that the levels were at the
assay detection limit by day 16. While serum EPO levels were
elevated over controls with the microparticles containing EPO and
10% pamidronate, levels did not remain above controls after day 23.
The serum EPO steady state level of the groups compared over day 9
through 27 showed a significant increase (p<0.05) in the group
receiving 10% pamidronate-containing microparticles (Table 5)
compared to the control group. Neither 1% or 10% containing
pamidronate microparticles lowered EPO burst significantly, nor did
it extend the steady state levels of EPO longer than control
animals.
5 TABLE 5 EPO-Containing Microparticles EPO, 20,000 U EPO, 20,000 U
20,000 U Pamidronate 1% Pamidronate 10% Cmax, mU/mL 43090.42
26308.30 31472.63 Tmax, day 1.00 1.00 1.00 AUC 0-1 d 21545.21
10718.10 11249.28 mU day/mL AUC 0-3 d, 52655.19 26229.50 24860.95
mU day/mL AUC d33, 97692.89 61599.38 63330.36 mU day/mL AUC (0-1)/
22.84 24.87 22.29 (0-last) % AUC (0-3)/ 56.22 59.59 46.79 (0-last)
% Average steady 54.12 13.82 125.64 state value (days 9-27):
[0136] Hematocrits were evaluated in the Groups X, Y and Z as a
measure of the pharmacodynamic effect of EPO (FIG. 6). No
significant effects were observed in the group receiving 1%
bisphosphonate relative to controls. When animals received 10%
bisphosphonate incorporated within EPO-containing microparticles,
hematocrits showed an upward trend over the time period between 9
to 37 days. The difference in hematocrits is statistically
different from controls on days 13 and 16 (p<0.05). This is
consistent with the enhanced PK values for the group receiving 10%
bisphosphonate observed between days 13 and 20.
[0137] The bisphosphonate, pamidronate was able to modulate both PK
and PD responses to EPO when co-encapsulated into ProLease
microspheres at a 10% nominal load. In this example, no increase in
persistence of EPO responses was observed. However, the pamidronate
did cause an elevation of EPO circulating serum levels for
approximately one week. This increase is also reflected in enhanced
pharmacodynamic responses.
[0138] While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
scope of the invention encompassed by the appended claims.
* * * * *