TREATMENT OF CANCERS WITH GAMMA INTERFERON

Abstract: Human gamma interferon is effective in treating certain human cancers. Its use for the manufacture of an appropriate medicament is disclosed.

Description: TREATMENT OF CANCERS WITH GAMMA INTERFERON BACKGROUND OF THE INVENTION This invention relates to a means of treating certain malignant diseases in humans with human-gamma interferon (hlFN-γ). Gamma interferon has a number of charac¬ teristics known in the art that differentiate it from alpha and beta interferons. Among these differences are antigenic distinctiveness and higher levels of immunoregulatory and an i umor activity. Human gamma interferon may be produced by T-lymphocytes stimulated by mitogens or by antigens to which they are sensitized. It may also be obtained through cloning and expression techniques now well known in the art. Although the source of the human gamma interferon used in this invention in not critical, it is required that such hlFN-γ is of a high purity material that is not contaminated by cell constitutents or cell debris of the interferon-expressing cell. A preferred hlFN-γ used in this invention is produced by recombinant DNA technology and then purified as taught in Japanese Patent Application No. 59-281376, filed December 12,1984 and foreign counterparts thereof, e.g. the European Patent Application, all of which are incorporated by reference herein. The purification process comprises adding one or more salts of 2inc or copper and polyethyleneimine in the extraction. More particularly, it comprises suspending the culture cells of a recombinant microorganism in a buffer solution containing one or more salts of zinc or copper, e.g. zinc chloride, zinc sulfate, zinc acetate, zinc acetylacetonate and copper sulfate, in a range of about 0.5 - 5mM in the case of zinc salts and 0.01 - 3mM in the case of copper salts, disrupting the cells, then adding polyethyleneimine to the centrifuged supernatant, e.g. to a final concentration of 0.5 - 1.1%, and subsequently purifying by a conventional method, e.g. combining several chromatographiσ methods and dialysis. Human gamma interferon can be made, for example, by the procedures disclosed in Gray et al, Nature, 295, 503-508 (1982) and Epstein, Nature, 295, 453-454 (1982). There has been speculation that components of interferon have antitumor properties in humans and tests with relatively impurified interferon have been conducted on animals, Gresser, Advan. Cancer Res. 16 97-140 (1972) and Gresser, Cancer-A Comprehensive Treatise, F. Becker editor, _5_, 521-571, Plenum Press, N.Y. (1977). However, there have been no conclusive studies of the effects of hlFN-γ on primary human cancer cells freshly obtained from patients. SUMMARY OF THE INVENTION This invention relates to a method of treating human ovarian, breast, lung, melanoma, kidney, pancreatic, cervical, colon, brain, pleural and stomach cancers by administering to a patient in need of such treatment a sufficient amount of purified human gamma interferon to be effective an an antitumor agent. The preferred mode of administration is parenteral, i.e. intravenous, intramuscular, subcutaneous and in raperitoneal. DETAILED DESCRIPTION It is possible to determine the antitumor activity of hlFN-γ by testing with cultured human tumors using a two-layer soft agar system as described by Hamburger et al. Science, 197, 461 (1977) and Hamburger et al., J. Clin Invest _60_, 846 (1977). This culture system, called the "human tumor cloning system" initially was used to select the most appropriate anticancer agent for an individual patient's tumor. Salmon, et al. , N. Eng. J. Med. 298. 1321 (1978) demonstrated that if a patient's tumor was sensitive to a drug in vitro, the chance of the patient responding clinically to the drug was 81 percent. However, if the patient's tumor was resistant to the drug in vitro, the chances of the patient not responding to the drug was 99%. In order to test human gamma interferon for antitumor activity against human tumors in the human tumor cloning system, the known capillary tube system is utilized. This system was developed by Von Hoff et al, Proc. Am. Assoc. Cancer Res. (1983). A positive control, mercuric chloride, which should destroy all the tumor colony forming units, is run alongside the recombinant human gamma interferon being tested. In conducting the tests, the following procedures are used. A. In order to determine if there is increasing cytotoxicity for human tumors with increasing concentrations of hlFN-γ, concentrations of 100 and 1,000 ng/ml of hlFN-γ were tested against the patients tumors cloned in soft agar. For these studies, all controls and hlFN-γ treated cells have 6 capillary tubes. The data obtained from these studies may provide leads as to whether higher doses of hlFN-γ are necessary for antitumor activity in the clinic. B. In order to determine whether continuous exposure to hlFN-γ produces more cytotoxicity for human tumor colony forming units than a brief pretreatment, one hour exposures at 10, 100 and 1,000 ng/ml are used and the results are compared to continuous exposure for up to 20 days at the same concentrations. The results of these concentration times time effects give guidance to the clinician in determining the most effective treatment regimen for specific cancer in a patient. The results of the continuous exposure test are shown in the following Table I and the results of the one-hour exposure test are shown in the following Table II. TABLE I Clonogenic Assay of Human Gaπma Interferon (Continuous Exposure) Human 50% or Less Colony Human Interferon Cancer Colony Survival Concentration (No. of responders/No. Tested) ng/ml ovarian 3/9 10, 100 and 1,000 lung (non-small cell) 1/11 100 and 1,000 lung (unknown) 1/1 100 and 1,000 melanoma 1/6 1,000 kidney 1/1 1,000 pancreatic 1/2 1,000 cervical 1/1 100 and 1,000 colon 1/4 1,000 brain 1/1 1,000 pleural 1/2 100 stomach 1/3 The data in Table I shows that human gamma interferon has antitumor activity against the cancers listed. TABLE II Clonogenic Assay of Human Gamma Interferon (One-hour) Human 50% or Less Colony Human Interferon Cancer Colony Survival Concentration (No. of responders/No. tested) ng/ml lung (non-small cell) 1/3 10 ovarian 2/3 100 and 1,000 pancreatic 1/1 1,000 The tests show that results from one-hour exposure to human gamma interferon are similar to those obtained following continuous exposure. The dosage of hlFN-γ administered as well as the regimen and form of administration is dependent on the judgement of the clinician, taking into account a variety of factors including the patient's tumor's response to hlFN-γ. Human gamma interferon is preferably administered parenterally, e.g. intravenously (IV), intramuscularly (IM) , subcutaneously (SO or intraperitoneally (IP), in conventional dosage forms, i.e. sterile aqueous solutions or suspensions. The formulations for these conventional dosage forms include the active compound and conventional pharmaceutically acceptable carriers, adjuvants, fillers, binders, disintegrants and the like. Typically the hlFN-γ will be parenterally administered, on a per day basis, in the range of about 0.1 mg to 10 mg and preferably from about 0.1 mg to 10 mg in divided doses.

Claims: CLAIMS : 1. A method of treating human cancers selected from ovarian, breast, lung, melanoma, kidney, pancreatic, cervical, colon, brain, pleural, and stomach which comprises administering to a human in need of such treatment a sufficient amount of human gamma interferon to be effective as an antitumor agent. 2. The method of claim 1 wherein the human gamma interferon is purified recombinant human gamma interfero . 3. Use of human gamma interferon for the manufacture of a medicament for effective therapeutic treatment of human cancers selected from ovarian, breast, lung, melanoma, kidney, pancreatic, cervical, colon, brain, pleural, and stomach. 4. Use as claimed in claim 3, wherein the human gamma interferon is purified recombinant human gamma interferon.

Inventors: NAGABHUSHAN TATTANAHALI L, TROTTA PAUL PHILIP, NAGABHUSHAN, TATTANAHALI, L., TROTTA, PAUL, PHILIP
Applicants: SCHERING CORP, SCHERING CORPORATION
Application year: 1987
Main classification: A61K45
IPC codes: A61K38, A61P35