U.S. patent application number 12/266727 was filed with the patent office on 2009-10-15 for methods for modulating tumor growth and metastasis.
Invention is credited to David Chaplin, Klaus Edvardsen, Francis Y. Lee, Ronald Peck, Ronald Pero.
Application Number | 20090258937 12/266727 |
Document ID | / |
Family ID | 36216012 |
Filed Date | 2009-10-15 |
United States Patent
Application |
20090258937 |
Kind Code |
A1 |
Lee; Francis Y. ; et
al. |
October 15, 2009 |
Methods for Modulating Tumor Growth and Metastasis
Abstract
Methods and pharmaceutical compositions for modulating tumor
growth or metastasis are provided.
Inventors: |
Lee; Francis Y.; (Yardley,
PA) ; Peck; Ronald; (Cheshire, CT) ; Chaplin;
David; (Oxfordshire, GB) ; Pero; Ronald;
(Arlington, VT) ; Edvardsen; Klaus; (Lund,
SE) |
Correspondence
Address: |
OXIGENE, INC.;C/O LAW OFFICES OF KAREN E. FLICK
P.O. BOX 515
EL GRANDA
CA
94108-0515
US
|
Family ID: |
36216012 |
Appl. No.: |
12/266727 |
Filed: |
November 7, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11415731 |
May 1, 2006 |
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12266727 |
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10027186 |
Dec 20, 2001 |
7037906 |
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11415731 |
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60258195 |
Dec 22, 2000 |
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Current U.S.
Class: |
514/449 ;
514/720 |
Current CPC
Class: |
A61P 35/00 20180101;
A61K 31/05 20130101; A61K 31/337 20130101; A61K 31/66 20130101;
A61K 31/05 20130101; A61K 2300/00 20130101; A61K 31/337 20130101;
A61K 2300/00 20130101; A61K 31/66 20130101; A61K 2300/00
20130101 |
Class at
Publication: |
514/449 ;
514/720 |
International
Class: |
A61K 31/337 20060101
A61K031/337; A61K 31/09 20060101 A61K031/09; A61P 35/00 20060101
A61P035/00 |
Claims
1-60. (canceled)
61. A method for modulating tumor growth or metastasis in an animal
in need thereof, comprising sequential or simultaneous
administration of a taxane and a combretastatin compound in amounts
effective therefore.
62. The method of claim 61, wherein said taxane is selected from
the group consisting of paclitaxel and docetaxel.
63. The method of claim 61, wherein said combretastatin compound is
a combretastatin A-4 compound.
64. The method of claim 63, wherein said combretastatin A-4
compound is combretastatin A-4 phosphate.
65. The method of claim 63, wherein said combretastatin A-4
phosphate is administered at least 3 hours prior to the taxane.
66. The method of claim 61, wherein said combretastatin compound is
a combretastatin A-1 compound.
67. The method as claimed in claim 66, wherein said combretastatin
A-1 compound is combretastatin A-1 phosphate.
68. The method as claimed in claim 66, wherein said combretastatin
A-1 compound is combretastatin A-1 phosphate and said taxane is
paclitaxel.
69. The method as claimed in claim 68, wherein said combretastatin
A-1 phosphate is administered at least 3 hours prior to
paclitaxel.
70. A method for modulating tumor growth or metastasis in an animal
in need thereof, comprising administration of a combretastatin
compound and a taxane, in amounts effective therefor, wherein said
combretastatin compound is administered at a time relative to
administration of said taxane sufficient to modulate blood flow to
said tumor to provide a time-dependent effective tumor
concentration of said taxane.
71. A pharmaceutical composition for modulating tumor growth or
metastasis in an animal in need thereof, comprising a taxane and a
combretastatin compound, in amounts effective therefore in a
pharmaceutically acceptable carrier.
72. The pharmaceutical composition as claimed in claim 71, wherein
said taxane is paclitaxel or docetaxel.
73. The pharmaceutical composition of claim 71, wherein said
combretastatin compound is a combretastatin A-4 compound.
74. The pharmaceutical composition of claim 71, wherein said
combretastatin compound is a combretastatin A-1 compound.
Description
[0001] This application claims priority to U.S. Provisional
Application 60/258,195, filed Dec. 22, 2000, entitled "Methods For
Modulating Tumor Growth and Metastasis".
FIELD OF THE INVENTION
[0002] This invention relates to the fields of oncology and
improved chemotherapy regimens.
BACKGROUND OF THE INVENTION
[0003] The disclosure of each literature article and published
patent document referred to herein is incorporated by reference
herein in its entirety.
[0004] Cellular transformation during the development of cancer
involves multiple alterations in the normal pattern of cell growth
regulation. Primary events in the process of carcinogenesis involve
the activation of oncogene function by some means (e.g.,
amplification, mutation, chromosomal rearrangement), and in many
cases, the removal of anti-oncogene function. In the most malignant
and untreatable tumors, normal restraints on cell growth are
completely lost as transformed cells escape from their primary
sites and metastasize to other locations in the body. One reason
for the enhanced growth and invasive properties of some tumors may
be the acquisition of increasing numbers of mutations in oncogenes,
with cumulative effect (Bear et al., Proc. Natl. Acad. Sci. USA
86:7495-7499, (1989)).
[0005] Alternatively, insofar as oncogenes function through the
normal cellular signaling pathways required for organismal growth
and cellular function (reviewed in McCormick, Nature 363:15-16,
(1993)), additional alterations in the oncogenic signaling pathways
may also contribute to tumor malignancy (Gilks et al., Mol. Cell.
Biol. 13:1759-1768, (1993)), even though mutations in the signaling
pathways alone may not cause cancer.
[0006] Several discrete classes of proteins are known to be
involved in bringing about the different types of changes in cell
division properties and morphology associated with transformation.
These changes can be summarized as, first, the promotion of
continuous cell cycling (immortalization); second, the loss of
responsiveness to growth inhibitory signals and cell apoptotic
signals; and third, the morphological restructuring of cells to
enhance invasive properties.
[0007] The National Cancer Institute has estimated that in the
United States alone, 1 in 3 people will be struck with cancer
during their lifetime. Moreover approximately 50% to 60% of people
contracting cancer will eventually succumb to the disease. The
widespread occurrence of this disease underscores the need for
improved anticancer regimens for the treatment of malignancy.
[0008] Due to the wide variety of cancers presently observed,
numerous anticancer agents have been developed to destroy cancer
within the body. These compounds are administered to cancer
patients with the objective of destroying or otherwise inhibiting
the growth of malignant cells while leaving normal, healthy cells
undisturbed. Anticancer agents have been classified based upon
their mechanism of action. One type of chemotherapeutic is referred
to as a metal coordination complex. It is believed this type of
chemotherapeutic forms predominantly inter-strand DNA cross links
in the nuclei of cells, thereby preventing cellular replication. As
a result, tumor growth is initially repressed, and then reversed.
Another type of chemotherapeutic is referred to as an alkylating
agent. These compounds function by inserting foreign compositions
or molecules into the DNA of dividing cancer cells. As a result of
these foreign moieties, the normal functions of cancer cells are
disrupted and proliferation is prevented. Another type of
chemotherapeutic is an antineoplastic agent. This type of agent
prevents, kills, or blocks the growth and spread of cancer cells.
Still other types of anticancer agents include nonsteroidal
aromastase inhibitors, bifunctional alkylating agents, etc.
[0009] Unfortunately, deleterious side effects are associated with
each of these agents. For example, fluorouracil, a commonly used
antineoplastic agent causes swelling or redness of normal skin,
black or tarry stools, blood in the urine, chest pain, confusion,
diarrhea, shortness of breath, and drowsiness. Administration of
fluorouracil has also been associated with fever, chills, cough,
sore throat, lower back pain, mouth sores, nausea, vomiting, pain
and/or difficulty passing urine. Taxane administration has been
associated with cardiovascular events such as syncope, rhythm
abnormalities, hypertension and venous thrombosis; bone marrow
suppression; neutropenia; anemia; peripheral neuropathy
arthralgia/myalgia; nausea/vomiting and alopecia, to name only a
few.
[0010] Combretastatins are another class of anticancer agents.
Combretastatins have been isolated from stem wood of the African
tree combretum caffrum (Combretaceae), and are potent inhibitors of
microtubulin assembly. Combretastatin A-4 (CA-4) is significantly
active against the US National Cancer Institute's (NCI) murine
L1210 and P338 lymphocytic leukemia cell lines. In addition, CA-4
was found to compete with combretastatin A-1 (CA-1), another
compound isolated from Combretum caffrum, as a potent inhibitor of
colchicine binding to tubulin. CA-4 also strongly retards the
growth of certain cell lines (ED50<0.01 (g/ml), and is a
powerful anti-mitotic agent. See U.S. Pat. No. 4,996,237.
Furthermore, an "anti-vascular" mechanism of action for both CA-4
and CA-1 has recently been discovered. Since the solubility of the
combretastatins is very limited, prodrugs have been developed, such
as combretastatin A-4 phosphate disodium salt and combretastatin
A-1 phosphate disodium salt(hereinafter "CA4P" and "CA1P"
respectively), to increase the solubility, and thus the efficacy of
CA-4 and CA-1. In particular, a number of studies have shown that
administration of combretastatin A-4 disodium salt or
combretastatin A-1 phosphate disodium salt causes an extensive
shut-down of blood flow to the tumor vasculature, leading to
secondary tumor cell death. Toxic side effects of CA-4 have also
been reported.
[0011] There is thus a need in the art to provide superior
effective anticancer therapies which minimize patient exposure and
the unwanted side effects associated with such agents.
SUMMARY OF THE INVENTION
[0012] The present invention provides effective therapeutic methods
for modulating tumor growth or metastasis wherein a combination of
agents is employed. The methods of the present invention provide
advantages such as greater overall efficacy, for example, in
achieving synergy or avoiding antagonism, and allow, where desired,
a reduction in the amount of one or more of the individual agents
employed with a concomitant reduction in side effects. Further,
where the tumor to he treated is not optimally responsive to a
given anticancer agent, use of the present combination therapy
methods can nonetheless provide effective treatment.
[0013] In particular, the present invention provides a method for
modulating tumor growth or metastasis in an animal, especially a
human, in need thereof, comprising sequential or simultaneous
administration of a combretastatin A-4 compound or combretastatin
A-1 compound and at least one other anticancer agent, in amounts
effective therefor. Preferred such agents are described further
below. The method of the present invention can provide the
aforementioned advantages.
[0014] Further, the present inventors have found that certain
sequences of administering the combretastatin A-4 compound or
combretastatin A-1 compound and the other anticancer agent can, in
vivo, potentiate the overall efficacy of the combination.
Combretastatin A-4 compounds or combretastatin A-1 compounds, as
antivascular agents, modulate blood flow to tumor tissue. By timing
the administration of the combretastatin A-4 compound or
combretastatin A-1 compound to modulate the flow of blood to the
tumor to provide a time-dependent effective tumor concentration of
the other anticancer agent, the overall efficacy of the combination
is potentiated.
[0015] Without wishing to be bound by any molecular theory of
action, certain anticancer agents are most efficacious at
relatively high tumor concentrations, but are rapidly cleared from
tumor tissue. For such agents, the present inventors have found
that simultaneous administration of the combretastatin A-4 compound
or combretastatin A-1 compound and the other anticancer agent
potentiates the effect of the combination. Simultaneous
administration allows the other anticancer agent to rapidly
accumulate to a peak concentration in tumor tissue, yet "traps" the
agent as the vasulature clearing tumor tissue is disrupted by the
combretastatin A-4 compound or combretastatin A-1 compound. Such
agents are termed herein "Peak Tumor Concentration Agents". Peak
Tumor Concentration Agents are thus preferably administered
simultaneously with, or within close temporal proximity to, the
combretastatin A-4 compound or combretastatin A-1 compound.
[0016] Other agents, for example, need not be present at high
concentrations, but are effective during a relatively short period
of the overall cell cycle. As such agents can become protein-bound
and inactive over time when remaining in contact with tumor tissue,
they are therefore most efficacious under conditions where a
continuing supply of the agent reaches the tumor. Potentiation of
the efficacy of combination therapy in these cases can be obtained
by administering the anticancer agent and combretastatin A-4
compound or combretastatin A-1 compound sequentially, with
sufficient delay between administrations to allow the action of one
of the agents before the other. Thus, when such anticancer agent is
administered first, followed by a delay before administering the
combretastatin A-4 compound or combretastatin A-1 compound, the
anticancer agent reaches the tumor tissue over a sufficient
duration to allow action of the compound, with subsequent
administration of the combretatatin A-4 compound or combretastatin
A-1 compound further damaging tumor tissue.
[0017] When the combretastatin A-4 compound or combretastatin A-1
compound is administered first, followed by a delay to allow blood
flow to the tumor to resume before administering the anticancer
agent, the tumor is initially weakened by the combretastatin A-4
compound or combretastatin A-1 compound, followed by further damage
to the tumor by the anticancer agent. In this latter case, duration
of anticancer agent tumor concentration is more significant than
peak concentration. The damage to tumor vasculature by the initial
administration of the combretastin A-4 compound or combretastatin
A-1 compound does not prevent the relatively low concentration of
anticancer agent needed from reaching the tumor tissue once blood
flow resumes. Such agents are termed herein "Duration Exposure
Agents". Duration Exposure Agents and the combretastatin A-4
compound or combretastatin A-1 compound are thus preferably
administered sequentially, with either administration of the
combretastatin A-4 compound or combretastatin A-1 compound first,
followed by the anticancer agent, or vice versa, provided that a
sufficient delay is allowed between administrations to potentiate
the combination. Administration of the anticancer agent after the
administration of combretastatin A-4 compound or combretastatin A-1
compound is most preferred for Duration Exposure Agents.
[0018] In yet an additional embodiment of the methods of the
invention, certain agents are most efficacious when present at
relatively high concentrations in tumor tissue over a longer
duration (i.e., maximizing the "area under the curve" (AUC) of a
plot of concentration over time). Administering such agents first,
followed by a delay before administering the combretastatin A-4
compound or combretastatin A-1 compound, allows action of the
anticancer agent, with subsequent administration of the
combretastatin A-4 compound or combretastatin A-1 compound further
weakening the tumor tissue. For such agents, administration of the
anticancer agent first avoids premature damage to tumor vasculature
and allows sufficient concentrations of anticancer agent to reach
the tumor. Such agents are termed herein "High AUC Agents". High
AUC Agents and the combretastatin A-4 compound or combretastatin
A-1 compound are thus preferably administered sequentially, with
administration of the High AUC Agent preceding administration of
the combretastatin A-4 compound or combretastatin A-1 compound,
provided that a sufficent delay is allowed between administrations
to potentatiate the combination.
[0019] The present invention therefore provides as a further
embodiment, a method for modulating tumor growth or metastasis in
an animal in need thereof, especially a human, comprising
administration of a combretastatin A-4 compound or combretastatin
A-1 compound and at least one anticancer agent, in amounts
effective therefor, wherein said combretastatin A-4 compound or
combretastatin A-1 compound is administered at a time relative to
administration of said anticancer agent sufficient to modulate
blood flow to said tumor to provide a time-dependent effective
tumor concentration of said anticancer agent. The method of the
present invention allows potentiation of the overall efficacy of
the combination employed.
[0020] The term "time-dependent effective tumor concentration," as
used herein, denotes a concentration of the other anticancer agent
in the tumor tissue over time (i.e, from administration until the
agent is cleared from the body) which potentiates the action of the
combination of the combretastatin A-4 compound or combretastatin
A-1 compound and other anticancer agent. Thus, where the
combination is otherwise antagonistic, "potentiation" can denote
use of a combination without antagonistic results. "Potentiation"
can also denote achieving an unexpected improvement in the overall
efficacy of the combination, such as synergy.
[0021] Where simultaneous administration of the combretastatin A-4
compound or combretastatin A-1 compound and at least one anticancer
agent is contemplated, the present invention also provides
pharmaceutical compositions comprising at least one anticancer
agent and a combretastatin A-4 compound or combretastatin A-1
compound. For example, in one aspect, the anticancer agent and/or
combretastatin A-4 compound or combretastatin A-1 compound can be
present in a subtherapeutic dose for the individual agent, the
agents being effective in combination, providing reduced side
effects while maintaining efficacy. Alternatively, each agent can
be provided at higher doses for the individual agent, such as those
found in the Physician's Desk Reference.
[0022] Where simultaneous or sequential administration of the
combretastatin A-4 compound or combretastatin A-1 compound and
anticancer agent is contemplated, the present invention further
provides pharmaceutical kits. Exemplary kits of the invention
comprise a first pharmaceutical composition comprising at least one
anticancer agent and a second pharmaceutical composition comprising
a combretastatin A-4 compound or combretastatin A-1 compound
together in a package. The anticancer agent and/or combretastatin
A4 compound or combretastatin A-1 compound can be present, for
example, in a subtherapeutic dose for the individual agent, the
agents being effective in combination and providing reduced side
effects while maintaining efficacy. Alternatively, each agent can
be provided at a higher dose, such as those found for the agent in
the Physician's Desk Reference.
[0023] The following definitions are provided to facilitate an
understanding of the present invention.
[0024] As used herein, the term "combretastatin A-4 compound"
denotes at least one of combretastatin A-4, prodrugs (preferably
phosphate prodrugs) and derivatives thereof, and salts of these
compounds. Such compounds include without limitation,
combretastatin A-4, and various prodrugs of combretastatin A-4
exemplified by combretastatin A-4 phosphate and salts thereof,
especially combretastatin A-4 phosphate disodium salt. Preferred
combretastatin A-4 compounds contemplated for use in the methods of
the invention are described in WO 00/48606; WO 99/35150; U.S. Pat.
No. 5,561,122; U.S. Pat. No. 4,996,237; U.S. Provisional
Application Ser. No. 60/232,568, filed Sep. 14, 2000 by John J.
Venit, entitled "Combretastatin A-4 phosphate Mono- and Di-Amino
Acid Salt Prodrugs" disclosing compounds of the formula I:
##STR00001##
wherein one of OR.sup.1 and OR.sup.2 is --O.sup.-QH.sup.+, and the
other is hydroxyl or --O.sup.-QH.sup.+, and Q is an amino acid
containing at least two nitrogen atoms where one of the nitrogen
atoms, together with a proton, forms a quaternary ammonium cation
QH.sup.+, preferably, where one of OR.sup.1 and OR.sup.2 is
hydroxyl, and the other is --O.sup.-QH.sup.+ where Q is
L-histidine; and U.S. Provisional Application Ser. No. 60/251,921,
filed Dec. 7, 2000 by Mandar V. Dali et al., entitled
"Combretastatin A-4 Phosphate Prodrug Mono- and Di-Organic Amine
Salts" disclosing compounds having the structure shown in formula I
above, wherein one of OR.sup.1 and OR.sup.2 is --O.sup.-QH.sup.+,
and the other is hydroxyl or --O.sup.-QH.sup.+; and Q is an organic
amine containing at least one nitrogen atom which, together with a
proton, forms a quaternary ammonium cation, QH.sup.+, preferably,
where one of OR.sup.1 and OR.sup.2 is hydroxyl and the other is
--O.sup.-QH.sup.+ and Q is tris(hydroxymethyl)amino methane
("TRIS"). As mentioned above, each of these documents is
incorporated herein by reference in its entirety.
[0025] As used herein, the term combretastatin A-1 compound denotes
as least one of combretastatin A-1, prodrugs (preferably phosphate
prodrugs) and derivatives thereof, and salts of these compounds.
Combretastatin A-1 is described in U.S. Pat. No. 5,409,953 to
Pettit et al. and has the following general structure:
##STR00002##
[0026] As used herein, the terms "modulate", "modulating" or
"modulation" refer to changing the rate at which a particular
process occurs, inhibiting a particular process, reversing a
particular process, and/or preventing the initiation of a
particular process. Accordingly, if the particular process is tumor
growth or metastasis, the term "modulation" includes, without
limitation, decreasing the rate at which tumor growth and/or
metastasis occurs; inhibiting tumor growth and/or metastasis;
reversing tumor growth and/or metastasis (including tumor shrinkage
and/or eradication) and/or preventing tumor growth and/or
metastasis.
[0027] The term "anticancer agent" as used herein denotes a
chemical compound or electromagnetic radiation (especially, X-rays)
which is capable of modulating tumor growth or metastasis. When
referring to use of such an agent with a combretastatin A-4
compound or combretastatin A-1 compound, the term refers to an
agent other than a combretastatin A-4 compound or combretastatin
A-1 compound. Unless otherwise indicated, this term can include
one, or more than one, such agents. Thus, the term "anticancer
agent" encompasses the use of one or more chemical compounds and/or
electomagnetic radiation in the present methods and compositions.
Where more than one anticancer agent is employed, the relative time
for administration of the combretastatin A-4 compound or
combretastatin A-1 compound can, as desired, be selected to provide
a time-dependent effective tumor concentration of one, or more than
one, of the anticancer agents.
[0028] As explained above, numerous types of anticancer agents are
exemplary of those having applications in a composition or method
of the present invention. Such classes of anticancer agents, and
their preferred mechanisms of action, are described below:
[0029] 1. Alkylating agent: a compound that donates an alkyl group
to nucleotides. Alkylated DNA is unable to replicate itself and
cell proliferation is stopped. Examples of such compounds include,
but are not limited to, busulfan, coordination metal complexes
(such as carboplatin, oxaliplatin, and cisplatin), cyclophosphamide
(cytoxan), dacarbazine, ifosfamide, mechlorethamine (mustargen),
and melphalan;
[0030] 2. Bifunctional alkylating agent: a compound having two
labile methanesulfonate groups that are attached to opposite ends
of a four carbon alkyl chain. The methanesulfonate groups interact
with, and cause damage to DNA in cancer cells, preventing their
replication. Examples of such compounds include, without
limitation, chlorambucil and melphalan;
[0031] 3. Non-steroidal aromatase inhibitor: a compound that
inhibits the enzyme aromatase, which is involved in estrogen
production. Thus, blockage of aromatase results in the prevention
of the production of estrogen. Examples of such compounds include
anastrozole and exemstane;
[0032] 4. Immunotherapeutic agent: an antibody or antibody fragment
which targets cancer cells that produce proteins associated with
malignancy. Exemplary immunotherapeutic agents include Herceptin
which targets HER2 or HER2/neu, which occurs in high numbers in
about 25 percent to 30 percent of breast cancers; and anti-CD20
which triggers apoptosis in B cell lymphomas. Additional
immunotherapeutic agents include immunotoxins, wherein toxin
molecules such as ricin, diphtheria toxin and pseudomonas toxins
are conjugated to antibodies which recognize tumor specific
antigens. Conjugation can be achieved biochemically or via
recombinant DNA methods.
[0033] 5. Nitrosurea compound: inhibits enzymes that are needed for
DNA repair. These agents are able to travel to the brain so they
are used to treat brain tumors, as well as non-Hodgkin's lymphomas,
multiple myeloma, and malignant melanoma. Examples of nitrosureas
include carmustine and lomustine;
[0034] 6. Antimetabolite: a class of drugs that interfere with DNA
and ribonucleic acid (RNA) elongation. These agents are phase
specific (S phase) and are used to treat chronic leukemias as well
as tumors of breast, ovary and the gastrointestinal tract. Examples
of antimetabolites include 5-fluorouracil, methotrexate,
gemcitabine (GEMZAR), cytarabine (Ara-C), and fludarabine.
[0035] 7. Antitumor antibiotic: a compound having antimicrobial and
cytotoxic activity. Such compounds also may interfere with DNA by
chemically inhibiting enzymes and mitosis or altering cellular
membranes. Examples include, but certainly are not limited to
bleomycin, dactinomycin, daunorubicin, doxorubicin (Adriamycin),
and idarubicin;
[0036] 8. Mitotic inhibitor: a compound that can inhibit mitosis
(e.g., tubulin binding compounds) or inhibit enzymes that prevent
protein synthesis needed for reproduction of the cell. Examples of
mitotic inhibitors include taxanes such as paclitaxel and
docetaxel, epothilones, etoposide, vinblastine, vincristine, and
vinorelbine;
[0037] 9. Radiation therapy: includes but is not limited to X-rays
or gamma rays which are delivered from either an externally
supplied source such as a beam or by implantation of small
radioactive sources.
[0038] 10. Topoisomerase I inhibitors: agents which interfere with
topoisomerase activity thereby inhibiting DNA replication. Such
agents include, without limitation, CPT-11 and topotecan.
[0039] 11. Hormonal therapy: includes, but is not limited to
anti-estrogens, such as Tamoxifen, GnRH agonists, such as Lupron,
and Progestin agents, such as Megace.
[0040] Naturally, other types of anticancer agents that function
via a large variety of mechanisms have application in the
pharmaceutical compositions and methods of the present invention.
Additional such agents include for example, leuocovorin, kinase
inhibitors, such as Iressa and Flavopiridol, analogues of
conventional chemotherapeutic agents such as taxane analogs and
epothilone analogues, antiangiogenics such as matrix
metalloproteinase inhibitors, and other VEGF inhibitors, such as
ZD6474 and SU6668. Retinoids such as Targretin can also be employed
in the pharmaceutical compositions and methods of the invention.
Signal transduction inhibitors which interfere with farnesyl
transferase activity and chemotherapy resistance modulators, e.g.,
Valspodar can also be employed. Monoclonal antibodies such as C225
and anti-VEGFr antibodies can also be employed.
[0041] As used herein, the phrase "effective amount" of a compound
or pharmaceutical composition refers to an amount sufficient to
modulate tumor growth or metastasis in an animal, especially a
human, including without limitation decreasing tumor growth or size
or preventing formation of tumor growth in an animal lacking any
tumor formation prior to administration, i.e., prophylactic
administration.
[0042] As used herein, the term "prodrug" refers to a precursor
form of the drug which is metabolically converted in vivo to
produce the active drug. Thus, for example, combretastatin A-4
phosphate prodrug salts or combretastatin A-1 phosphate prodrug
salts administered to an animal in accordance with the present
invention undergo metabolic activation and regenerate
combretastatin A-4 or combretastatin A-1 in vivo, e.g., following
dissociation and exposure to endogenous non-specific phosphatases
in the body.
[0043] As explained above, the present invention is directed
towards a pharmaceutical composition that modulates growth or
metastasis of tumors, particularly solid tumors, using a
pharmaceutical composition of the present invention, along with
methods of modulating tumor growth or metastasis, for example, with
a pharmaceutical composition of the present invention.
[0044] As used herein, the terms "tumor", "tumor growth" or "tumor
tissue" can be used interchangeably, and refer to an abnormal
growth of tissue resulting from uncontrolled progressive
multiplication of cells and serving no physiological function. A
solid tumor can be malignant, e.g. tending to metastasize and being
life threatening, or benign. Examples of solid tumors that can be
treated or prevented according to a method of the present invention
include sarcomas and carcinomas such as, but not limited to:
fibrosarcoma, myxosarcoma, liposarcoma, chondrosarcoma, osteogenic
sarcoma, chordoma, angiosarcoma, endotheliosarcoma,
lymphangiosarcoma, lymphangioendotheliosarcoma, synovioma,
mesothelioma, Ewing's tumor, leiomyosarcoma, rhabdomyosarcoma,
colon carcinoma, colorectal cancer, gastic cancer, pancreatic
cancer, breast cancer, ovarian cancer, prostate cancer, squamous
cell carcinoma, basal cell carcinoma, adenocarcinoma, sweat gland
carcinoma, sebaceous gland carcinoma, papillary carcinoma,
papillary adenocarcinomas, cystadenocarcinoma, medullary carcinoma,
bronchogenic carcinoma, renal cell carcinoma, hepatoma, liver
metastases, bile duct carcinoma, choriocarcinoma, seminoma,
embryonal carcinoma, thyroid carcinoma such as anaplastic thyroid
cancer, Wilms'tumor, cervical cancer, testicular tumor, lung
carcinoma such as small cell lung carcinoma and non-small cell lung
carcinoma, bladder carcinoma, epithelial carcinoma, glioma,
astrocytoma, medulloblastoma, craniopharyngioma, ependymoma,
pinealoma, hemangioblastoma, acoustic neuroma, oligodendroglioma,
meningioma, melanoma, neuroblastoma, and retinoblastoma.
[0045] Moreover, tumors comprising dysproliferative changes (such
as metaplasias and dysplasias) can be treated or prevented with a
pharmaceutical composition or method of the present invention in
epithelial tissues such as those in the cervix, esophagus, and
lung. Thus, the present invention provides for treatment of
conditions known or suspected of preceding progression to neoplasia
or cancer, in particular, where non-neoplastic cell growth
consisting of hyperplasia, metaplasia, or most particularly,
dysplasia has occurred (for review of such abnormal growth
conditions, see Robbins and Angell, 1976, Basic Pathology, 2d Ed.,
W.B. Saunders Co., Philadelphia, pp. 68 to 79). Hyperplasia is a
form of controlled cell proliferation involving an increase in cell
number in a tissue or organ, without significant alteration in
structure or function. For example, endometrial hyperplasia often
precedes endometrial cancer. Metaplasia is a form of controlled
cell growth in which one type of adult or fully differentiated cell
substitutes for another type of adult cell. Metaplasia can occur in
epithelial or connective tissue cells. Atypical metaplasia involves
a somewhat disorderly metaplastic epithelium. Dysplasia is
frequently a forerunner of cancer, and is found mainly in the
epithelia; it is the most disorderly form of non-neoplastic cell
growth, involving a loss in individual cell uniformity and in the
architectural orientation of cells. Dysplastic cells often have
abnormally large, deeply stained nuclei, and exhibit pleomorphism.
Dysplasia characteristically occurs where there exists chronic
irritation or inflammation, and is often found in the cervix,
respiratory passages, oral cavity, and gall bladder. For a review
of such disorders, see Fishman et al., 1985, Medicine, 2d Ed., J.
B. Lippincott Co., Philadelphia.
[0046] Other examples of tumors that are benign and can be treated
or prevented in accordance with a method of the present invention
include arteriovenous (AV) malformations, particularly in
intracranial sites and myoleomas.
[0047] The phrase "Peak Tumor Concentration Agents" refers to
anticancer agents which are most efficacious at high tumor
concentrations yet are rapidly cleared from the tumor tissue. Such
agents are preferably administered simultaneously with or in close
temporal proximity to (e.g., as is clinically feasible, especially
within one hour of) the administration of the combretastatin A-4
compound or combretastatin A-1 compound in accordance with the
invention. Exemplary Peak tumor Concentration Agents include,
without limitation, alklating agents such as cytoxan and mitomycin
C and metal coordination complexes such as cisplatin, oxaliplatin
and carboplatin.
[0048] The phrase "Duration Exposure Agents" as used herein refers
to agents which can be effective at relatively low tumor
concentrations yet which require certain tumor tissue exposure
times to be most effective. Such agents are preferably administered
sequentially in any order with a combretastatin A-4 compound or
combretastatin A-1 compound in accordance with the invention,
provided that a sufficient delay is allowed between administrations
to potentiate the combination. In a preferred embodiment of the
method of the invention, the Duration Exposure Agent is
administered after the administration of the combretastatin A-4
compound or combretastatin A-1 compound. Exemplary Duration
Exposure Agents include, without limitation, taxanes such as
paclitaxel and docetaxel, etoposide, etoposide phosphate,
immunotoxins, and epothilones.
[0049] The phrase "High AUC Agents" as used herein refers to those
agents which show greatest efficacy when present at high
concentrations in tumor tissue for extended time periods. Such
agents are preferably administered sequentially with a
combretastatin A-4 compound or combretastatin A-1 compound in
accordance with the invention, wherein the High AUC Agent is
administered first, followed by the combretastatin A-4 compound or
combretastatin A-1 compound, provided that a sufficient delay is
allowed between administrations to potentiate the combination.
Exemplary High AUC Agents include, without limitation, adriamycin,
CPT-11 (irinotecan), and topotecan.
[0050] In one preferred embodiment, Peak Tumor Concentration
Agents, such as platinum based anticancer agents, including
cisplatin or carboplatin are administered essentially
simultaneously with a combretastatin A-4 compound or combretastatin
A-1 compound, such as combretastatin A-4 phosphate disodium salt or
combretastatin A-1 phosphate disodium salt.
[0051] In yet another preferred embodiment, Duration Exposure
Agents, including immunotoxins, and taxanes, such as paclitaxel and
docetaxel are administered after the combretastatin A-4 compound or
combretastatin A-1 compound. Administration of a combretastatin A-4
compound or combretastatin A-1 compound prior to the Duration
Exposure Agent extends the exposure time of the tumor tissue to the
Duration Exposure Agent.
[0052] In an additional preferred embodiment, High AUC Agents such
as CPT-11, are administered prior to the administration of the
combretastatin A-4 compound or combretastatin A-1 compound (e.g.,
combretastatin A-4 phosphate disodium salt or combretastatin A-1
phosphate disodium salt). Such agents can preferably be
administered, for example, within 24 hours of the administration of
the combretastatin A-4 compound or combretastatin A-1 compound,
such as within 2-24 hours prior, 3-24 hours prior, 6-24 hours
prior, 8-24 hours prior, or 12 to 24 hours prior to
administration.
[0053] Surprisingly, combinations such as those described above
potentiate the efficacy of the combination and can provide the
advantages described above. For example, the present methods permit
the clinician to administer a combretastatin A-4 compound or
combretastatin A-1 compound, such as the phosphate disodium salts
of these compounds, and/or anticancer agent, at dosages which are
significantly lower than those employed for the single agent.
Preferred dosages suitable for administration of the anticancer and
combretastatin A-4 compounds or combretastatin A-1 compounds in
accordance with the invention are set forth hereinbelow.
[0054] Whether administered simultaneously or sequentially, the
combretastatin A-4 compound or combretastatin A-1 compound and the
at least one anticancer agent can be administered in any amount or
by any route of administration effective for the modulation of
tumor growth or metastasis, especially treatment of cancer as
described herein. The expression "chemotherapeutically effective
amount", as used herein, refers to a sufficient amount of the
compounds of the invention to provide the desired anticancer
effect. The exact amount required will vary from subject to
subject, the mode of administration of the chemotherapeutic
compounds and the like.
[0055] The present invention further provides chemotherapeutic
pharmaceutical compositions comprising both a combretastatin A-4
compound or combretastatin A-1 compound, and at least one selected
anticancer agent and the use thereof in the present methods.
Alternatively, the method of the present invention can be carried
out using chemotherapeutic pharmaceutical compositions which
comprise one of the above-described compounds as the active
ingredient, in combination with a pharmaceutically acceptable
carrier medium or an auxiliary agent. Thus, in such an embodiment,
the combretastatin A-4 compound or combretastatin A-1 compound,
such as combretastatin A-4 phosphate disodium salt or
combretastatin A-1 phosphate disodium salt, and the anticancer
agent, such as cisplatin are formulated and administered
separately.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1: Graph of the antitumor activity of cisplatin and
combretastain A-4 phosphate disodium salt (CA4P) administered
singly in the moderately platinum-resistant M5076DDP murine
fibrosarcoma. Tumor was staged to 300 mg at treatment initiation.
Cisplatin was administered intravenously (iv), every 4 days for 3
doses (Q4D .times.3). CA4P was given iv, every day for 10 days
(Monday through Friday).
[0057] FIG. 2: (A) Graph of therapeutic synergy observed with the
combination of CA4P and the Peak Tumor Concentration Agent,
cisplatin in the M5076DDP tumor model. Drug treatment was iv, Q4D
.times.3. Drug combinations were administered simultaneously. (B)
Graph showing CA4P significantly enhanced the antitumor activity of
an otherwise inactive dose of cisplatin (3 mg/kg/inj).
[0058] FIG. 3: (A) Graph of therapeutic synergy observed with the
combination of CA4P and the peak tumor concentration agent,
carboplatin in the M5076 murine fibrosarcoma model. Drug treatment
was intraperitoneal (ip), Q4D .times.3. Drug combinations were
administered simultaneously ip (admixed). (B) Graph showing that
CA4P, at three different dose levels (90-250 mg/kg/inj),
significantly improved the antitumor activity of carboplatin.
[0059] FIG. 4: A graph showing antitumor activity in log cell kill
indicating that the CA4P and carboplatin should essentially be
administered simultaneously.
[0060] FIG. 5: Graph of inhibition of tumor blood flow by CA4P in
the sc A2780 human ovarian carcinoma grown in nude mice (A) or nude
rats (B).
[0061] FIG. 6: Graph showing the antitumor effects of combined High
AUC Agent, CPT-11, and CA4P chemotherapy in human ovarian carcinoma
cells (A2780). CPT-11 is administered 3-24 hours prior to the
administration of the combretastatin compound.
[0062] FIG. 7: Enhancement of the antitumor efficacy of carboplatin
by low dose CA4P in the M5076/DDP tumors. Panels A-C depict results
for the combination of various doses of CA4P with 90, 60 and 40
mg/m.sup.2 of carboplatin, respectively.
[0063] FIG. 8: Combination chemotherapy with CA4P and paclitaxel
versus the 16/c murine mammary carcinoma.
[0064] FIG. 9: Combination chemotherapy with CA4P and paclitaxel
versus A2780 human ovarian carcinoma. Simultaneous administration
of the agents is antagonistic in this model.
[0065] FIG. 10: Combination chemotherapy with CA4P and paclitaxel
versus A2780 human ovarian carcinoma. An interval of 3 hours
between treatments abrogates negative interaction.
[0066] FIG. 11: A bar graph showing that combined administration of
an immunotoxin BR96-sFv-PE40 with combretastatin A4P acts
synergistically to reduce tumor size in a colon cancer xenograft
model in an allogeneic Brown-Norway rat host.
[0067] FIGS. 12A and 12B: A pair of graphs showing that
combretastatin A-1P inhibits blood flow in human tumor xenografts
in nude mice in a manner comparable to that observed for
combretastatin A-4P. FIG. 12A: N87 gastric cancer xenograft model;
FIG. 12B: A2780 ovarian cancer xenograft model.
[0068] FIGS. 13A-13D are a series of graphs showing dose response
curves of tumor size reduction in response to administration of
combretastatin A-1P and carboplatin alone and in combination
against an M5076 fibrosarcoma xenograft model. Combined
administration of combretastatin A-1P and carboplatin acted
synergistically to reduce tumor size.
[0069] FIG. 14: Graph showing that combined administration of
combretastatin A-1P and carboplatin produces a synergistic
antitumor effect, producing a complete response (disappearance of
tumors) not observed in single agent therapy.
[0070] FIG. 15: A graph showing that combined administration of
cisplatin and combretastatin A1P act synergistically to reduce
tumor size in a CaNT breast tumor model in CBA mice.
DETAILED DESCRIPTION OF THE INVENTION
[0071] In accordance with the present invention, improved
chemotherapeutic regimens are provided for the treatment of cancer.
The improved chemotherapeutic regimens can lower side effects and
enhance efficacy for the treatment of neoplastic disease.
[0072] Derived from the South African tree Combretum caffrum,
combretastatin A-4 (CA-4) was initially identified in the 1980's as
a potent inhibitor of tubulin polymerization. CA-4 binds a site at
or near the colchicine binding site on tubulin with high affinity.
In vitro studies clearly demonstrated that CA-4 is a potent
cytotoxic agent against a diverse spectrum of tumor cell types in
culture. Combretastatin A-4 has also recently been shown to have an
additional "anti-vascular" mechanism of action. A number of studies
have shown that CA4P causes extensive shut-down of blood flow to
the tumor vasculature, leading to secondary tumor cell death. Blood
flow to normal tissues is generally far less affected by
combretastatin A-4 than tumors, although blood flow to some organs,
such as spleen, skin, skeletal muscle and brain, can be inhibited.
In light of this new "non-cytotoxic" mode of action of CA4P, there
is considerable interest in exploiting the novel anti-vascular
action of CA4P for cancer treatment. Recently, single agent
efficacy was reported for CA4P using a frequent dosing regimen.
Another report suggested that large tumors can, in some cases, be
more responsive to CA4P therapy than small tumors.
[0073] Combretastatin A-1 and prodrugs thereof (CA1P) are also
potent inhibitors of tubulin polymerization. CA1P has also been
shown to cause shut down of blood flow to the tumor
vasculature.
Pharmaceutical Compositions
[0074] As explained above, the present methods can, for example, be
carried out using a single pharmaceutical composition comprising
both combretastatin A-4 compound or combretastatin A-1 compound and
anticancer agent(s) (when administration is to be simultaneous) or
using two or more pharmaceutical compositions separately comprising
combretastatin A-4 compound or combretastatin A-1 compound and
anticancer agent(s) (when administration is to be simultaneous or
sequential). Such pharmaceutical compositions can comprise, inter
alia, at least one anticancer agent and/or a combretastatin A-4
compound or combretastatin A-1 compound, such as combretastatin A-4
phosphate disodium salt or combretastatin A-1 phosphate disodium
salt and a pharmaceutically acceptable carrier. The phrase
"pharmaceutically acceptable" refers to molecular entities and
compositions that are physiologically tolerable and preferably do
not produce an allergic or similar untoward reaction, such as
gastric upset, dizziness and the like, when administered to a
human.
[0075] Preferably, as used herein, the term "pharmaceutically
acceptable" means approved by a regulatory agency of the Federal or
a state government or listed in the U.S. Pharmacopeia or other
generally recognized pharmacopeia for use in animals, and more
particularly in humans. The term "carrier" refers, for example to a
diluent, adjuvant, excipient, auxilliary agent or vehicle with
which an active agent of the present invention is administered.
Such pharmaceutical carriers can be sterile liquids, such as water
and oils, including those of petroleum, animal, vegetable or
synthetic origin, such as peanut oil, soybean oil, mineral oil,
sesame oil and the like. Water or aqueous saline solutions and
aqueous dextrose and glycerol solutions are preferably employed as
carriers, particularly for injectable solutions. Suitable
pharmaceutical carriers are described in "Remington's
Pharmaceutical Sciences" by E. W. Martin.
[0076] A pharmaceutical composition of the present invention can be
administered by any suitable route, for example, by injection, by
oral, pulmonary, nasal or other forms of administration. In
general, pharmaceutical compositions contemplated to be within the
scope of the invention, comprise, inter alia, pharmaceutically
acceptable diluents, preservatives, solubilizers, emulsifiers,
adjuvants and/or carriers. Such compositions can include diluents
of various buffer content (e.g., Tris-HCl, acetate, phosphate), pH
and ionic strength; additives such as detergents and solubilizing
agents (e.g., Tween 80, Polysorbate 80), anti-oxidants (e.g.,
ascorbic acid, sodium metabisulfite), preservatives (e.g.,
Thimersol, benzyl alcohol) and bulking substances (e.g., lactose,
mannitol); incorporation of the material into particulate
preparations of polymeric compounds such as polylactic acid,
polyglycolic acid, etc., or into liposomes. Such compositions may
influence the physical state, stability, rate of in vivo release,
and rate of in vivo clearance of components of a pharmaceutical
composition of the present invention. See, e.g., Remington's
Pharmaceutical Sciences, 18th Ed. (1990, Mack Publishing Co.,
Easton, Pa. 18042) pages 1435-1712 which are herein incorporated by
reference. A pharmaceutical composition of the present invention
can be prepared, for example, in liquid form, or can be in dried
powder, such as lyophilized form. Particular methods of
administering such compositions are described infra.
Methods for Modulating Tumor Growth or Metastasis
[0077] As explained above, the present invention is directed
towards methods for modulating tumor growth and metastasis
comprising, inter alia, the administration of a combretastatin A-4
compound or combretastatin A-1 compound, such as combretastatin A-4
phosphate disodium salt or combretastatin A-1 phosphate disodium
salt, and at least one anticancer agent. The agents of the
invention can be administered separately (e.g, formulated and
administered separately), or in combination as a pharmaceutical
composition of the present invention. Administration can be
achieved by any suitable route, such as parenterally,
transmucosally, e.g., orally, nasally, or rectally, or
transdermally. Preferably, administration is parenteral, e.g., via
intravenous injection. Alternative means of administration also
include, but are not limited to, intra-arteriole, intramuscular,
intradermal, subcutaneous, intraperitoneal, intraventricular, and
intracranial administration, or by injection into the tumor(s)
being treated or into tissues surrounding the tumor(s).
[0078] The combretastatin A-4 compound or combretastatin A-1
compound, such as combretastatin A-4 phosphate disodium salt or
combretastatin A-1 phosphate disodium salt and anticancer agent may
be employed in any suitable pharmaceutical formulation, as
described above, including in a vesicle, such as a liposome [see
Langer, Science 249:1527-1533 (1990); Treat et al., in Liposomes in
the Therapy of Infectious Disease and Cancer, Lopez-Berestein and
Fidler (eds.), Liss: New York, pp. 317-327, see generally, ibid]
Preferably, administration of liposomes containing the agents of
the invention is parenteral, e.g., via intravenous injection, but
also may include, without limitation, intra-arteriole,
intramuscular, intradermal, subcutaneous, intraperitoneal,
intraventricular, and intracranial administration, or by injection
into the tumor(s) being treated or into tissues surrounding the
tumor(s).
[0079] In yet another embodiment, a pharmaceutical composition of
the present invention can be delivered in a controlled release
system, such as using an intravenous infusion, an implantable
osmotic pump, a transdermal patch, liposomes, or other modes of
administration. In a particular embodiment, a pump may be used [see
Langer, supra; Sefton, CRC Crit. Ref. Biomed. Eng. 14:201 (1987);
Buchwald et al., Surgery 88:507 (1980); Saudek et al., N. Engl. J.
Med. 321:574 (1989)]. In another embodiment, polymeric materials
can be used [see Medical Applications of Controlled Release, Langer
and Wise (eds.), CRC Press: Boca Raton, Fla. (1974); Controlled
Drug Bioavailability, Drug Product Design and Performance, Smolen
and Ball (eds.), Wiley: New York (1984); Ranger and Peppas, J.
Macromol. Sci. Rev. Macromol. Chem. 23:61 (1983); see also Levy et
al., Science 228:190 (1985); During et al., Ann. Neurol. 25:351
(1989); Howard et al., J. Neurosurg. 71:105 (1989)]. In yet another
embodiment, a controlled release system can be placed in proximity
of the target tissues of the animal, thus requiring only a fraction
of the systemic dose [see, e.g., Goodson, in Medical Applications
of Controlled Release, supra, vol. 2, pp. 115-138 (1984)]. In
particular, a controlled release device can be introduced into an
animal in proximity of the site of inappropriate immune activation
or a tumor. Other controlled release systems are discussed in the
review by Langer [Science 249:1527-1533 (1990)]. The following
Table I sets forth preferred chemotherapeutic combinations and
exemplary dosages for use in the methods of the present invention.
Where "Combretastatin A-4" appears, combretastatin A-4,
combretastatin A-1 or a phosphate prodrug salt of either
combretastatin A-4 or combretastatin A-1 or, such as CA4P or CA1P,
is preferably employed.
TABLE-US-00001 CHEMOTHERAPEUTIC DOSAGE COMBINATION mg/m.sup.2 (per
dose) Combretastatin A-4 1-100 mg/m2 +Cisplatin 5-150 mg/m2
Combretastatin A-4 1-100 mg/m2 +Carboplatin 5-1000 mg/m2
Combretastatin A-4 1-100 mg/m2 +Radiation 200-8000 cGy
Combretastatin A-4 1-100 mg/m2 +CPT-11 5-400 mg/m2 Combretastatin
A-4 1-100 mg/m2 +Paclitaxel 40-250 mg/m2 Combretastatin A-4 1-100
mg/m2 +Paclitaxel 40-250 mg/m2 +Carboplatin 5-1000 mg/m2
Combretastatin A-4 1-100 mg/m2 +5FU and optionally 5-5000 mg/m2
+Leucovorin 5-1000 mg/m2 Combretastatin A-4 1-100 mg/m2 +Epothilone
1-500 mg/m2 Combretastatin A-4 1-100 mg/m2 +Gemcitabine 100-3000
mg/m2 Combretastatin A-4 1-100 mg/m2 +UFT and optionally 50-800
mg/m2 +leucovorin 5-1000 mg/m2 Combretastatin A-4 1-100 mg/m2
+Gemcitabine 100-3000 mg/m2 +Cisplatin 5-150 mg/m2 Combretastatin
A-4 1-100 mg/m2 +UFT 50-800 mg/m2 +Leucovorin 5-1000 mg/m2
Combretastatin A-4 1-100 mg/m2 +Cisplatin 5-150 mg/m2 +paclitaxel
40-250 mg/m2 Combretastatin A-4 1-100 mg/m2 +Cisplatin 5-150 mg/m2
+5FU 5-5000 mg/m2 Combretastatin A-4 1-100 mg/m2 +Oxaliplatin 5-200
mg/m2 +CPT-11 4-400 mg/m2 Combretastatin A-4 1-100 mg/m2 +5FU
5-5000 mg/m2 +CPT-11 and optionally 4-400 mg/m2 +leucovorin 5-1000
mg/m2 Combretastatin A-4 1-100 mg/m2 +5FU 5-5000 mg/m2 +radiation
200-8000 cGy Combretastatin A-4 1-100 mg/m2 +radiation 200-8000 cGy
+5FU 5-5000 mg/m2 +Cisplatin 5-150 mg/m2 Combretastatin A-4 1-100
mg/m2 +Oxaliplatin 5-200 mg/m2 +5FU and optionally 5-5000 mg/m2
+Leucovorin 5-1000 mg/m2 Combretastatin A-4 1-100 mg/m2 +paclitaxel
40-250 mg/m2 +CPT-11 4-400 mg/m2 Combretastatin A-4 1-100 mg/m2
+paclitaxel 40-250 mg/m2 +5-FU 5-5000 mg/m2 Combretastatin A-4
1-100 mg/m2 +UFT 50-800 mg/m2 +CPT-11 and optionally 4-400 mg/m2
+leucovorin 5-1000 mg/m2 Combretastatin A-4 1-100 mg/m2
+BR96-sFv-PE40 100-750 mg/m2
[0080] In the above Table I, "5FU" denotes 5-fluorouracil,
"Leucovorin" can be employed as leucovorin calcium, "UFT" is a 1:4
molar ratio of tegafur:uracil, and "Epothilone" is preferably a
compound described in WO 99/02514 or WO 00/50423, both incorporated
by reference herein in their entirety.
[0081] While Table I provides exemplary dosage ranges of the
combretastatin A-4 compounds or combretastatin A-1 compounds and
certain anticancer agents of the invention, when formulating the
pharmaceutical compositions of the invention the clinician may
utilize preferred dosages as warranted by the condition of the
patient being treated. For example, combretastatin A-4 compounds or
combretastatin A-1 compounds may preferably be administered at a
dosage ranging from 30-70 mg/m2 every three weeks for as long as
treatment is required. Preferred dosages for cisplatin are 75-120
mg/m2 administered every three weeks. Preferred dosages for
carboplatin are within the range of 200-600 mg/m2 or an AUC of
0.5-8 mg/ml.times.min; most preferred is an AUC of 4-6
mg/ml.times.min. When the method employed utilizes radiation,
preferred dosages are within the range of 200-6000 cGY. Preferred
dosages for CPT-11 are within 100-125 mg/m2, once a week. Preferred
dosages for paclitaxel are 130-225 mg/m2 every 21 days. Preferred
dosages for gemcitabine are within the range of 80-1500 mg/m2
administered weekly. Preferably UFT is used within a range of
300-400 mg/m2 per day when combined with leucovorin administration.
Preferred dosages for leucovorin are 10-600 mg/m2 administered
weekly. A preferred dose of the Br96-sFv-PE40 immunotoxin is 420
mg/m2. The use of the BR96-sFv-PE40 immunotoxin in combination with
combretastatin A4 and its prodrugs in immune enhancing therapy is
described in U.S. Provisional Application 60/258,283, filed Dec.
26, 2000, the entire disclosure of which is incorporated by
reference herein.
[0082] Certain cancers can be treated effectively with
combretastatin A-4 or combretastatin A-1 and a plurality of
anticancer agents. Such triple and quadruple combinations can
provide greater efficacy. When used in such triple and quadruple
combinations the dosages set forth above can be utilized. Other
such combinations in the above Table I can therefore include
"combretastatin A-4 or combretastatin A-1" in combination with (1)
mitoxantrone+prednisone; (2) doxorubicin+taxane; or (3)
herceptin+taxane. 5-FU can be replaced by UFT in any of the above
combinations.
[0083] When employing the methods or compositions of the present
invention, other agents used in the modulation of tumor growth or
metastasis in a clinical setting, such as antiemetics, can also be
administered as desired.
[0084] The following examples are provided to illustrate
embodiments of the invention. They are not intended to limit the
invention in any way.
[0085] The following protocols are provided to facilitate the
practice of Examples I and II.
Drug administration: For administration to rodents, CA4P was
dissolved in normal saline (0.9% NaCl). Paclitaxel was dissolved in
a 50/50 mixture of ethanol and Cremophor.RTM. and stored at
4.degree. C.; final dilution of paclitaxel was obtained immediately
before drug administration with NaCl 0.9%. Fresh preparation of
paclitaxel was employed to avoid precipitation. CPT-11 was
dissolved in normal saline.
[0086] The volume of all compounds injected was 0.01 ml/g of mice,
and 0.005 ml/g of rats.
In Vivo Antitumor Testing: The following tumor models were used:
A2780 human ovarian carcinoma, the murine fibrosarcoma M5076 and
M5076/ddp (resistant to cisplatin and carboplatin).
[0087] The human tumors were maintained in Balb/c nu/nu nude mice.
M5076 and M5076ddp was maintained in C57BL/6 mice. Tumors were
propagated as subcutaneous transplants in the appropriate mouse
strain using tumor fragments obtained from donor mice.
[0088] The following tumors were passaged in the indicated host
strain of mouse: murine M5076 fibrosarcoma (M5076) in C57B1/6 mice;
human A2780 ovarian carcinomas in nude mice. Tumor passage occurred
biweekly for murine tumors and approximately every two to three
weeks for the human tumor line. With regard to efficacy testing,
M5076 and M5076ddp tumors were implanted in (C57B1/6.times.DBA/2)F1
hybrid mice, and human tumors were implanted in nude mice. All
tumor implants for efficacy testing were subcutaneous (sc).
[0089] The required number of animals needed to detect a meaningful
response were pooled at the start of the experiment and each was
given a subcutaneous implant of a tumor fragment (50 mg) with a
13-gauge trocar. For treatment of early-stage tumors, the animals
were again pooled before distribution to the various treatment and
control groups. For treatment of animals with advanced-stage
disease, tumors were allowed to grow to the pre-determined size
window (tumors outside the range were excluded) and animals were
evenly distributed to various treatment and control groups.
Treatment of each animal was based on individual body weight.
Treated animals were checked daily for treatment related
toxicity/mortality. Each group of animals was weighed before the
initiation of treatment (Wt1) and then again following the last
treatment dose (Wt2). The difference in body weight (Wt2-Wt1)
provides a measure of treatment-related toxicity.
[0090] Tumor response was determined by measurement of tumors with
a caliper twice a week, until the tumors reach a predetermined
"target" size of 1 gm. Tumor weights (mg) were estimated from the
formula:
Tumor weight=(length.times.width2)/2
Antitumor activity was evaluated at the maximum tolerated dose
(MTD) which is defined as the dose level immediately below which
excessive toxicity (i.e. more than one death) occurred. The MTD was
frequently equivalent to OD. When death occurs, the day of death
was recorded. Treated mice dying prior to having their tumors reach
target size were considered to have died from drug toxicity. No
control mice died bearing tumors less than target size. Treatment
groups with more than one death caused by drug toxicity were
considered to have had excessively toxic treatments and their data
were not included in the evaluation of a compound's antitumor
efficacy.
[0091] Tumor response end-point was expressed in terms of tumor
growth delay (T-C value), defined as the difference in time (days)
required for the treated tumors (T) to reach a predetermined target
size compared to those of the control group (C).
[0092] To estimate tumor cell kill, the tumor volume doubling time
was first calculated with the formula:
TVDT=Median time (days) for control tumors to reach target
size-Median time (days) for control tumors to reach half the target
size and, Log cell kill=T-C/(3.32.times.TVDT)
[0093] Statistical evaluations of data were performed using Gehan's
generalized Wilcoxon test.
Example I
[0094] Combretastatin A-4 phosphate disodium salt, an agent with a
dual mechanism of action, was evaluated for in vivo antitumor
activity with the Peak Concentration Agents, cisplatin and
carboplatin. When administered daily as a single agent for ten days
to tumor bearing mice, combretastatin A-4 phosphate disodium salt
demonstrated significant antitumor activity against the
cisplatin-resistant M5076DDP murine fibrosarcoma, producing 1.1 log
cell kill. See FIG. 1.
[0095] In a combination chemotherapy trial, therapeutic synergy was
observed with both cisplatin and carboplatin. In tumor perfusion
studies, combretastatin A-4 phosphate disodium salt significantly
inhibited tumor blood flow in the A2780 human ovarian tumor
xenografts in mice (67% inhibition) and in rats (87%
inhibition).
[0096] In order to better assess the therapeutic potential of
combretastatin A-4 phosphate disodium salt, studies were conducted
to evaluate three aspects of CA4P's pharmacology: [1] antitumor
efficacy as a single agent, [2] antitumor efficacy in combination
with cisplatin, carboplatin, paclitaxel, or CPT-11 and [3] effects
on tumor blood flow.
Results
Single Agent Efficacy Against the Cisplatin-resistant sc M5076DDP
Tumor Model
[0097] M5076DDP is a murine fibrosarcoma that has developed
resistance to cisplatin and cross-resistance to carboplatin.
Combretastatin A-4 phosphate disodium salt treatment of mice
bearing staged M5076DDP tumors using an everyday.times.10 (Monday
thru Friday) schedule produced moderate but significant antitumor
effects. At its optimal dose (150 mg/kg/inj), combretastatin A-4
phosphate disodium salt yielded 1.1 log cell kill (LCK). In
comparison, single agent cisplatin administered at its optimal
schedule (every four days for three doses; Q4D.times.3) yielded 0.8
LCK at its MTD of 7.5 mg/kg/inj (FIG. 1).
Combination Chemotherapy with Platinum Drugs
[0098] Therapeutic synergy was achieved when combretastatin A-4
phosphate disodium salt was combined with cisplatin (administered
simultaneously) in the treatment of advanced staged (300 mg) sc
M5076DDP tumors. Single agent cisplatin produced 0.8 LCK at its
maximum tolerated dose (MTD) of 7.5 mg/kg/inj, q4d.times.3. In
comparison, the maximally tolerated combination of combretastatin
A-4 phosphate disodium salt (250 mg/kg/inj)+Cisplatin (5 mg/kg/inj)
yielded 2.0 LCK (FIG. 2A). It is of interest that the combination
produced significant shrinkage of tumors following treatment,
whereas single agent cisplatin did not (FIG. 1). Another noteworthy
aspect of this synergistic combination regimen is the ability of
combretastatin A-4 phosphate disodium salt to substantially improve
the efficacy of an otherwise inactive (lower) dose of cisplatin
(FIG. 2B).
Combination with Carboplatin (CPt) Versus Sc M5076
[0099] Combretastatin A-4 phosphate disodium salt also produced
synergistic antitumor activity when used in combination with
carboplatin against large sc M5076 tumors (H300 mg). In this
sensitive tumor model, carboplatin produced 1.4 LCK, but with no
tumor regression, at its MTD of 90 mg/kg/inj, iv, q4d.times.3. In
comparison the best combination yielded 2.0 LCK which was
accompanied by significant tumor shrinkage (FIG. 3A). Two important
aspects of the tumor response elicited by the combretastatin A-4
phosphate disodium salt+carboplatin combination regimen are [1] the
optimal combretastatin A-4 phosphate disodium salt dose required
for therapeutic synergy (<90 mg/kg/inj) was significantly lower
than its MTD as a single agent (>250 mg/kg/inj) (FIG. 3B); [2]
the carboplatin dose (90 mg/kg/inj) when administered as single
agent) required to produce optimal antitumor effects, is greatly
reduced when used in combination with combretastatin A-4 phosphate
disodium salt (FIG. 3B).
Timing Studies (Carboplatin+CA4P)
[0100] The data presented in FIG. 4 indicate that Carboplatin
("CB-pt") and CA4P are preferably administered more or less
simultaneously. Most preferably carboplatin is administered
immediately before CA4P. The tumor model shown in this graph is
M5076ddp (a platinum resistant variant of M5076 murine
fibrosarcoma).
Effects of CA4P on Tumor Perfusion
[0101] The effects of combretastatin A-4 phosphate disodium salt on
tumor perfusion were studied using the Evans blue dye uptake assay.
Mice or rats bearing sc A2780 human ovarian carcinoma were
administered an iv dose of combretastatin A-4 phosphate disodium
salt. An hour later, Evans blue was injected iv. The amount of
Evans blue accumulated in the tumor is proportional to the blood
flow through the tumor. Using this technique, it was shown that
CA4P dramatically inhibited blood flow to the tumors, both in mice
and rats, causing at optimal dose a 67% and 87% reduction of tumor
blood flow, respectively (FIGS. 5A and 5B).
Combination Chemotherapy with CPT-11
[0102] A combination chemotherapy study was conducted to evaluate
the antitumor activity of combined CPT-11 and combretastatin A-4
phosphate disodium salt treatment. Various dosing schedules were
used in accordance with the invention ranging from administering
the two agents virtually simultaneously (5 min apart) to CPT-1
preceding CA4P by 3 or 24 hrs. At its MTD, CPT-11 produced 3.3 LCK.
Administering the two agents simultaneously or 3 hr apart gave
equivalent results to CPT-11 alone. However, when CPT-11 preceded
CA4P by 24 hr, an enhanced antitumor effect was observed (FIG. 6)
demonstrating a preferred embodiment of the invention.
Minimum Efficacious Dose-pharmacokinetics Determination in
Combination with Carboplatin
[0103] Combretastatin A-4 has demonstrated robust therapeutic
synergism with cisplatin and carboplatin as shown herein. The doses
of combretastatin A-4 phosphate disodium salt (CA4P) used in these
previous combination studies has in general been between 100-250
mg/kg (200-750 mg/m.sup.2). Current human pharmacokinetics data
indicate that preferred CA4P dosing is considerably lower (-50-60
mg/m.sup.2). A study was therefore conducted to determine the
minimum CA4P dose needed for combination therapy with carboplatin
in the modestly carboplatin resistant murine fibrosarcoma
M5076/DDP. Using doses and treatment regimen (iv, q4d.times.3) of
CA4P that have no single agent activity, it was demonstrated that
CA4P at doses as low as 12.5-25 mg/m.sup.2 were sufficient to
enhance the antitumor activity of carboplatin administered at a
range of dose levels. See FIGS. 7A, 7B and 7C.
Determination of the Optimal Treatment Schedule for the Combination
of Combretastain A-4 Phosphate Disodium Salt (CA4P) with
Paclitaxel
[0104] The present invention contemplates, for example, the
administration of a combretastatin A-4 compound, such as CA4P with
paclitaxel or with paclitaxel and carboplatin. A number of studies
were conducted to determine an optimal treatment schedule, i.e, the
sequence or the order, in which the two agents, CA4P and paclitaxel
are administered. This consideration is deemed particularly
important for this combination for two reasons: 1) CA4P is a
tubulin depolymerizer while paclitaxel is a tubulin polymerizer,
thus there may be potential for interaction at the tubulin level;
and 2) CA4P inhibits tumor blood flow which may affect the regional
micro-pharmacokinetics of paclitaxel in the tumors as well as the
tumoral proliferative state. In an initial study in the 16/c
mammary carcinoma model, there was a suggestion that administering
the two agents simultaneously might adversely affect the overall
efficacy of the combination (FIG. 8) in this model, while allowing
an interval between drug administration restored the efficacy of
the combination. Subsequently two other studies were conducted in
the human ovarian carcinoma model A2780 to further define an
optimal sequence and interval between drug administrations.
[0105] An initial study was conducted to assess the effects of
administering paclitaxel simultaneously with CA4P or prior to CA4P.
Results indicate that administration of the two agents
simultaneously was deleterious to the overall efficacy of the
combination in this model (FIG. 9). Allowing an interval of 3 hr
between the administration of the two agents did not restore the
overall efficacy of the combination, but overall efficacy was
restored at an interval of 24 hours.
[0106] An additional study was conducted to evaluate the effects of
administering CA4P prior to paclitaxel. The results demonstrated
that allowing an interval of 3 hr between treatments with the two
agents was sufficient to avoid negative interaction (FIG. 10).
Combination Chemotherapy with Immunotoxin
[0107] Studies assessing the efficacy of combined administration of
CA4P with the immunotoxin BR96-sFv-PE40 were also conducted. The
construction of the immunotoxin is described in Siegall et al.
(1994) J. of Immunology 152:2377-2384.
[0108] Five groups of 5 rats each were inoculated intrahepatically
with 1.5.times.10.sup.5 wild type colon cancer cells (BN7005-HID2)
on day 0. BR96-sFv-PE40 is an immunoconjugate of BR96 monoclonal
antibody and Pseudomonas toxin PE40. BR96 recognizes Lewis y
antigen on the colon carcinoma BN7005 rat tumor. The immunotoxin
was inoculated at 2 different dose levels as indicated (125
.mu.g/kg or 150 .mu.g/kg respectively), on days 9, 12, 14, 16, 19,
21 and 23. Combretastatin A4-phosphate prodrug was administered ip
4-6 hours prior to the administration of the immunotoxin when
administered on the same day as the immunotoxin on days 7, 8, 9,
12, 13, 14, 14, 16, 19 and 20. All rats were lapartomized on day 28
and liver tumor sizes measured by a caliper and tumor volume
calculated.
[0109] As shown in FIG. 11, there was a significant different
between the treatment group and the untreated controls. The results
of the Student's t test are also shown in the figure. The
differences between the combined treatment and CA4P or immunotoxin
alone were also significant, p=0.002 and p=0.006, respectively.
When treatment was stopped on day 28, the tumor subsequently grew
rapidly in all groups. These data demonstrate the efficacy of CA4P
and immunotoxin when administered in combination.
Example II
Combination Chemotherapy with Combretastatin A-1P
[0110] Combretastatin A-1 phosphate disodium salt, an agent with a
dual mechanism of action, was evaluated for in vivo antitumor
activity with the Peak Concentration Agents, carboplatin, and
cisplatin. When administered daily as a single agent for ten days
to tumor bearing mice, combretastatin A-1 phosphate disodium salt
demonstrated modest antitumor activity against the
cisplatin-resistant M5076DDP murine fibrosarcoma.
[0111] In a combination chemotherapy trial, therapeutic synergy was
observed with both cisplatin and carboplatin. In tumor perfusion
studies, combretastatin A-1 phosphate disodium salt significantly
inhibited tumor blood flow in both A2780 human ovarian tumor
xenografts in mice and N87 gastric cancer tumor xenografts.
[0112] In order to better assess the therapeutic potential of
combretastatin A-1 phosphate disodium salt, studies were conducted
to evaluate three aspects of CA4P's pharmacology: [1] antitumor
efficacy as a single agent, [2] antitumor efficacy in combination
with cisplatin and carboplatin, and [3] effects on tumor blood
flow.
Results
Single Agent Efficacy Against N87 Gastric Cancer and A2780 Ovarian
Cancer Xenografts
[0113] CA1P demonstrated equivalent blood flow inhibition to that
observed with CA4P in human tumor xenografts in nude mice but was
5-10 times more potent. Additionally, CA1P has demonstrated
improved single agent activity in human tumor xenograft models,
including N87 human gastric carcinoma, and the A2780 ovarian
carcinoma. In A2780, CA1P achieved 2.1 LCK at its MTD of 9 mg/kg,
ip, q1d.times.8, compared to 1.1 LCK for CA4P at 150 mg/kg, ip. See
FIG. 12.
Combination Chemotherapy with Carboplatin and Cisplatin
[0114] As shown in FIG. 13, combination chemotherapy demonstrated
that CA1P enhanced the antitumor activity of carboplatin in a
manner similar to what had been observed for CA4P. Synergistic
antitumor activity was also demonstrated. Advantageously, the
minimum effective dose required for synergistic enhancement was
considerably lower for CA1P (4-8 mg/kg) as compared to CA4P (25-50
mg/kg). Additionally, when CA1P is administered in combination with
carboplatin, synergistic antitumor activity producing complete
response (disappearance of tumors) was observed. When either agent
was administered alone, this response was not observed. See FIG.
14.
[0115] In additional studies, CA1P was administered in combination
with cisplatin in a CaNT breasts tumor model I. As can be seen in
FIG. 15, combined administration of cisplatin and CA1P acted
synergistically to reduce tumor size.
CONCLUSION
[0116] The above described results readily demonstrate potentiation
for a variety of combinations of anticancer agents with a
combretastatin A-4 compound or combretastatin A-1 compound. Thus
anticancer agents can be effectively used to modulate tumor growth
or metastasis of tumors that previously had developed a resistance
to such drugs. Additionally, the present inventors have developed
methods for the treatment of cancer which permit the clinician to
administer lowered dosages of anticancer agents with appropriate
administration schedules thereby reducing unwanted side effects
while maintaining efficacy.
[0117] The present invention is not to be limited in scope by the
specific embodiments describe herein. Indeed, various modifications
of the invention in addition to those described herein will become
apparent to those skilled in the art from the foregoing description
and the accompanying figures. Such modifications are intended to
fall within the scope of the appended claims. For example, other
combretastatins or even other antivascular agents can be employed
in the present invention in place of the combretastatin A-4
compound or combretastatin A-1 compound.
* * * * *