Pharmaceutical compositions for treating metastasis of cancerous tumors

Abstract: A method of controlling metastasis of a cancerous tumor in a patient is disclosed. The method comprises administering a perfluorocarbon compound (PFC) emulsion to the patient at intervals of from about 3 to 14 days during a treatment period. PFC emulsion is administered initially in an amount of from about 2 to about 15 milliliters per kilogram of patient body weight. Subsequently administration of PFC emulsion do not exceed about 15 milliliters per kilogram of body weight. Oxy­ gen is administered daily for at least three days following each administration of PFC emulsion & preferably every day during the treatment period. Radiation and/or chemotherapeutic agents may be administered to the patient in conjunction with the administraction of PFC emulsion and oxygen.

Description: The present invention relates to pharmaceutical compositions for use in cancer therapy, in particular to a pharmaceutical composition comprising a tumoricidal chemotherapeutic agent and an oxygen carrying perfluorocarbon compound emulsion for administration to cancer patients to stimulate macrophage activity to thereby reduce metastasis and augment treatment of primary cancerous tumors. One of the greatest problems in the treatment of cancerous tumors is metastasis, i.e., the transmission of cells of the primary tumor to other locations in the patient and the establishment of new tumors at such locations. Metastasis is difficult to control because it often occurs before the primary tumor is diagnosed and treated. Also, the metastatic lesions may be at locations which limit the effective dosages of the treatments, e.g., radiation, due to the sensitivity of the surrounding tissue to such treatments. Further, metastatic cells are heterogeneous and cells which are resistant to conventional therapy tend to emerge. Conventional methods for treating metastasis include surgery, radiotherapy and/or chemotherapy. Other approaches which have been proposed include the use of monoclonal antibodies, hyperthermia, radiation sensitizing and protective drugs, and stimulated macrophages. It has been reported by Fidler et al in "Macrophages and Cancer Metastasis" that macrophages can be stimulated to become tumoricidal. Tumoricidal macrophages have the ability to discriminate between metastatic or tumorigenic and normal cells. Thus, although tumor cells are heterogeneous, they are all susceptible to lysis by the activated macrophages. Two pathways to achieve macrophage activation in vivo are disclosed. One pathway involves macrophage interaction with microorganisms or their products such as endotoxins, the bacterial wall skeleton and small components of the bacteria cell wall, e.g., muramyl dipeptide. Another pathway for activating macrophages involves the interaction of macrophages with soluble mediators released by sensitized lymphocytes, e.g., soluble lymphokine. Each of the above pathways has drawbacks. For example, water soluble synthetic muramyl dipeptide tends to be rapidly excreted by the body and therefore renders the macrophages tumoricidal for only a brief period. Lymphokine only activates the macrophages for three to four days after which the macrophages are resistant to reactivation. In animals it has been found that many of the drawbacks surrounding the activation of macrophages by lymphokine can be overcome by encapsulating the lymphokine within a liposome. Applicant's invention is based on the discovery that macrophage activity can be stimulated to reduce metastasis of cancerous tumors by the administration to the patient of a pharmaceutical composition comprising a chemotherapeutic agent in combination with an aqueous perfluorocarbon compound (PFC) emulsion. Accordingly, there is provided a pharmaceutical composition for reducing metastasis of a cancerous tumor in a patient which comprises a tumoricidal chemotherapeutic agent in combination with a unit dose of a 20% wt./vol. oxygen-carrying aqueous emulsion of a physiologically acceptable oxygen-transferable perfluorocarbon compound, from 2 to about 15 ml/kg body weight, preferably of from 4 to 10 ml/kg of emulsion. The pharmaceutical composition can be administered to the patient at intervals of from about 3 to about 14 days during a predetermined treatment period. The PFC emulsion is initially administered in an amount of from about 2 to about 15 milliliters of PFC emulsion per kilogram of body weight of the patient. Subsequent administrations preferably do not exceed about 15 milliliters and more preferably do not exceed about 10 milliliters of PFC emulsion per kilogram of patient body weight per week. Applicant has further found that such increased macrophage activity significantly enhances the effectiveness of radiotherapy and chemotherapy processes on primary tumor growth. A predetermined dosage of radiation, such as in the range of from about 1,000 to about 8,000 rads, can be given to the patient following administration of the pharmaceutical composition. The radiation can be administered in the fractionated doses at predetermined intervals. Each such fractionated dose is preferably in the range of from about 100 to about 600 rads and the frequency of radiation application is between 1 and 10 times per week for a period of between 2 and 8 weeks. In addition oxygen may be given to the patient for at least about 15 minutes and preferably from about 1 hour to about 4 hours for at least three days following the administration of the pharmaceutical composition. In accordance with the present invention, there is provided a pharmaceutical composition for stimulating macrophage tumoricidal activity to reduce metastasis of a cancerous tumor. The composition comprises a perfluorocarbon compound emulsion which may be given to the patient at least once and preferably two or more times at selected intervals. The intervals are preferably from about 3 to about 14 days, although intervals of up to about 21 days may be used in certain cases. Oxygen may be administered daily for a period of at least about three days after each administration of the pharmaceutical composition. The amounts of PFC emulsion described herein are expressed in milliliters of PFC emulsion containing about 20 grams of perfluorocarbon compound per 100 milliliters of emulsion ("20% wt./vol."). It is to be understood that emulsions containing more or less perfluorocarbon compound may be used in which case the indicated volumes should be increased proportionately for emulsions containing less than 20% perfluorocarbon compound and decreased proportionately for emulsions containing more than 20% perfluorocarbon compound emulsion. A unit dose of PFC emulsion in an amount greater than about 15 milliliters per kilogram of patient body weight is not preferred because such an amount tends to diminish the enhancement of the macrophage activity rather than stimulating such activity. It is believed that an amount greater than about 15 milliliters per kilogram of body weight overstimulates the macrophages rendering them less active than normal and indeed may be lethal to the macrophages. A unit dose of PFC emulsion less than about 2 milliliters per kilogram of patient body weight is not preferred because no beneficial stimulating effect is seen by the administration of such an amount of PFC emulsion. It is believed that such an amount is too small to significantly stimulate the macrophages. Amounts of PFC emulsion within the range of from about 4 to about 10 milliliters per kilogram of patient body weight are believed to provide the optimum combination of macrophage stimulation with minimal harm to the macrophages. As used herein, "perfluorocarbon compound emulsion" refers to an aqueous emulsion of an oxygen-transferable perfluorocarbon compound, preferably having a particle size of less than about 0.3 microns. Suitable emulsions have good oxygen transferability to ischemic, hypoxic and anoxic tissues, a favorable vapor pressure range to allow reasonable expiration of the perfluorocarbon compounds used in the emulsion and clinically acceptable toxicity, the emulsion may be transparent, translucent or opaque. The perfluorocarbon compound emulsion comprises at least one perfluorocarbon compound, an emulsifier and physiological salts and monoglycerides thereof. Such perfluorocarbon compound emulsions are described in U.S. Patents Nos. 3,911,138 to Clark, Jr., 3,962,439 to Yokoyama et al, and 4,252,827 to Yokoyama et al, Yokoyama, K. et al: "A Perfluorochemical Emulsion as an Oxygen Carrier", Artificial Organs 8:34-40, 1984, and Yokoyama, D. et al: "Selection of 53 PFC Substances for Better Stability of Emulsion and Improved Artificial Blood Substances", Advances in Blood Substitute Research , New York: Liss, Inc., 1983, Reiss, J. G.: "Reassessment of Criteria for the Selection of Perfluorochemicals for Second-Generation Blood Substitutes: Analysis of Structure/Property Relationships", Artificial Organs , 8:44-56, 1984, all of which are incorporated herein by reference. Preferred fluorocarbon compound emulsions comprise at least one perfluorocarbon compound having 9 to 11 carbon atoms selected from the group consisting of perfluorodecalin, perfluoromethyldecalin, perfluoro alkylcyclohexanes having 3 to 5 carbon atoms in the alkyl, perfluoro alkyltetrahydrofurans having 5 to 7 carbon atoms in the alkyl, perfluoro alkyltetrahydropyrans having 4 to 6 carbon atoms in the alkyl, perfluoroalkanes having 9 to 11 carbon atoms; and may have at least one perfluoro tert-amine having 9 to 11 carbon atoms selected from the group consisting of perfluoro tert-alkylamines having 9 to 11 carbon atoms, perfluoro N-alkylpiperidines having 4 to 6 carbon atoms in the alkyl and perfluoro N-alkylmorpholines having 5 to 7 carbon atoms in the alkyl. Such emulsions further comprise high-molecular-weight nonionic surfactant having a molecular weight of about 2,000 to 20,000; a phospholipid; and at least one fatty acid compound selected from the group consisting of fatty acids having 8 to 22 carbon atoms; and physiologically acceptable salts and monoglycerides thereof. The ratio of the perfluorocarbon compound and the said perfluoro tert-amine is 95-50 to 5-50 by weight. The "high-molecular-weight nonionic surfactant" has a molecular weight of 2,000 to 20,000 and includes polyoxyethylene-polyoxypropylene copolymers, polyoxyethylene alkyl ethers, and polyoxyethylene alkyl aryl ethers. The concentration of the surfactant in the emulsion is about 2.0 to about 5.0%, preferably 3.0 to 3.5% (W/V). The symbol "% (W/V)" means the amount proportion of a material by weight (gram) based on 100 milliliters of the resulting emulsion. Examples of the perfluorocarbons having 9 to 11 carbon atoms are a perfluorocycloalkane or perfluoro alkylcycloalkane which includes, for example, perfluoro C₃₋₅-alkylcyclohexanes such as perfluoromethylpropylcyclohexane, perfluorobutylcyclohexane, perfluorotrimethylcyclohexane, perfluoroethylpropylcyclohexane, perfluorodecalin and perfluoromethyldecalin; a perfluoro C₄₋₆-alkyltetrahydropyran such as perfluorohexyltetrahydropyran; a perfluoro C₅₋₇-alkyltetrahydrofuran such as perfluoro pentyltetrahydrofuran, perfluoro hexyltetrahydrofuran and perfluoro heptyltetrahydrofuran; and a perfluoroalkane having 9 to 11 carbon atoms such as perfluorononane and perfluorodecane. Examples of the perfluoro tert-amine having 9 to 11 carbon atoms are a perfluoro tert-alkylamine having 9 to 11 carbon atoms which includes, for example, perfluorotrialkylamines such as perfluoro N,N-dibutylmonomethylamine, perfluoro N,N-diethylpentylamine, perfluoro N,N-diethylhexylamine, perfluoro N,N-dipropylbutylamine and perfluorotripropylamine; a perfluoro N,N-dialkylcyclohexylamine having 9 to 11 carbon atoms such as perfluoro N,N-diethylcyclohexylamine; a perfluoro N-C₄₋₆-alkylpiperidine such as perfluoro N-pentylpiperidine, perfluoro N-hexylpiperidine and perfluoro N-butylpiperidine; and a perfluoro N-C₅₋₇-alkylmorpholine such as perfluoro N-pentylmorpholine, perfluoro N-hexylmorpholine and perfluoro N-heptylmorpholine. The ratio of the perfluorocarbon compound to the perfluoro tert-amine to be used is 50-95 to 50-5 by weight and the total amount of perfluorocarbon compound and perfluoro tert-amine contained in the emulsion is about 10 to about 50% (W/V). The phospholipids used as emulsifier adjuvant in the invention are ones commonly used in the art, and those comprising yolk phospholipid or soybean phospholipid are preferable. The amount present in the emulsion ranges from about 0.1 to about 1.0% (W/V), and preferably about 0.4 to about 0.6% (W/V). The fatty acid compound used as emulsifying adjuvant is a fatty acid having 8 to 22 carbon atoms, a physiologically acceptable salt such as sodium or potassium salt or a monoglyceride thereof, which includes, for example, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, palmitoleic acid, oleic acid, linoleic acid, arachidonic acid and sodium or potassium salts and monoglycerides thereof. These fatty acid compounds may be used alone or as a mixture of two or more kinds thereof in such a minor amount of 0.004 to 0.1% (W/V), and preferably about 0.02 to 0.04% (W/V). Among these fatty acid compounds, the preferable ones are those having 14 to 20 carbon atoms and their physiologically acceptable salts, and the most preferably are potassium palmitate and potassium oleate, taking into consideration of their good solubility and ease of the preparation of the emulsion. The presently preferred perfluorocarbon compound emulsion is manufactured by the Green Cross Corporation of Osaka, Japan and sold under the trade name Fluosol-DA. The specifics of the nature and composition of Fluosol-DA including the formulation thereof is described and claimed in U.S. Patent No. 4,252,827. Flusol is a registered U.S. trade mark of the Green Cross Corporation of Osaka, Japan. In addition to controlling the spread of cancer by metastasis, the pharmaceutical composition of the present invention is particularly useful in combination with radiotherapy in controlling the growth of primary metastatic cancerous tumors. Suitable chemotherapeutic agents for incorporation into the pharmaceutical compositions of the present invention, and which are not oxygen dependent, include androgens, estrogens, anti-estrogen, progestins, adrenal steroids, nitrogen mustard, thio-TEPA, busulfan, 6-mercaptopurine, 6-thioguanine, 5-fluorouracil, cytosine arabinoside, adriamycin, dactinomycin, daunomycin, bleomycin, mithramycin, mitomycin-C, CCNU, methyl-CCNU, DTIC, hydroxyurea, cis-platinum (cis-platinum (II) diamminedichloride), procarbazine, hexamethylmelamine, L-asparaginase, and the like. Lipophilic drugs such as alkylating agents as well as macrophage activity factors such as lymphokines may also be used. Some chemotherapeutic agents or drugs are known to be oxygen dependent, e.g., the presence of oxygen may be required for or may at least enhance the transport of the chemotherapeutic agent across the tumor cell membrane, may enhance cell cycling, and/or may enhance the toxicity or specificity of the chemotherapeutic agent toward tumor cells. Examples of such oxygen dependent chemotherapeutic agents include methotrexate, vinblastine, vincristine, cyclophosphamide and daunomycin, VP-16 and BCNU. It is believed that administration of the chemotherapeutic agent as a mixture with the PFC emulsion promotes delivery of the chemotherapeutic agent to the tumor via macrophage transport. It is believed that a chemotherapeutic agent dissolved in the PFC emulsion will be engulfed by macrophages which will then carry the chemotherapeutic agent to the tumor and the activity of the chemotherapeutic agent may be enhanced by the oxygen-carrying capacity of the PFC laden macrophage which may further stimulate the tumoricidal effect of the macrophage.

Claims: A pharmaceutical composition for reducing metastasis of a cancerous tumour comprising a tumoricidal chemotherapeutic agent in combination with a unit dose of from 2 to 15 ml/kg body weight of a 20% wt./vol. oxygen-carrying aqueous emulsion of a physiologically acceptable oxygen-transferable perfluorocarbon compound. A composition according to Claim 1, wherein the tumoricidal chemotherapeutic agent is selected from methotrexate, vinblastine, vincristine, daunomycin, VP-16, BCNU, androgens, estrogens, anti-estrogen, progestins, adrenal steroids, nitrogen mustard, cyclophosphamide, thio-TEPA, busulfan, 6-mercaptopurine, 6-thioguanine, 5-fluorouracil, cytosine arabinoside, adriamycin, dactinomycin, bleomycin, mithramycin, mitomycin-C, CCNU, methyl-CCNU, DTIC, hydroxyurea, cis-platinum (cis-platinum (II) diamminedichloride), procarbazine, hexamethylmalamine, and L-asparaginase. A composition according to Claim 1 or Claim 2, wherein the aqueous perfluorocarbon compound emulsion comprises at least one oxygen-transferable perfluorocarbon compound, an emulsifier, pysiological salts and monoglycerides thereof. A composition according to Claim 3, wherein the perfluorocarbon compound has 9 to 11 carbon atoms and is selected from perfluorodecalin, perfluoromethyldecalin, perfluoroalkylcyclohexanes having 3 to 5 carbon atoms in the alkyl, perfluoro alkyltetrahydrofurans having 5 to 7 carbon atoms in the alkyl, perfluoro alkyltetrahydropyrans having 4 to 6 carbon atoms in the alkyl, perfluoroalkanes having 9 to 11 carbon atoms. A composition according to Claim 3, wherein the emulsion also comprises at least one perfluorotert-amine having 9 to 11 carbon atoms selected from perfluorotertalkylamines having 9 to 11 carbon atoms, perfluoro-N-alkylpiperidines having 4 to 6 carbon atoms in the alkyl and perfluoro-N-alkylmorpholines having 5 to 7 carbon atoms in the alkyl. The use of a unit dose of from 2 to 15 ml/kg body weight of an aqueous emulsion of a physiologically acceptable oxygen-transferable perfluorocarbon compound for the manufacture of a medicament for stimulating macrophages. The use of a unit dose of from 2 to 15 ml/kg body weight of an aqueous emulsion of a physiologically acceptable oxygen-transferable perfluorocarbon compound, and a tumoricidal chemotherapeutic agent for the manufacture of a medicament mixture for stimulating macrophages to thereby reduce metastasis of a cancerous tumor.

Inventors: MCINTOSH-LOWE NORMA, ROSE CHRISTOPHER M, TEICHER BEVERLEY, MCINTOSH-LOWE, NORMA, ROSE, CHRISTOPHER M, TEICHER, BEVERLEY
Applicants: ALPHA THERAPEUTIC CORP, DANA FARBER CANCER INST INC, ALPHA THERAPEUTIC CORPORATION, DANA-FARBER CANCER INSTITUTE
Application year: 1986
Main classification: A61K31
IPC codes: A61K9, A61K41, A61K31, A61P35