MXPA99008176A - Method of treating a tumor - Google Patents

Abstract

In accordance with the present invention there is provided a method of treating a mammal having a solid tumor, the method comprising:a) administering to the mammal an effective amount of 3-amino-1,2,4-benzotriazine 1,4-dioxide;b) administering to the mammal an effective amount of paclitaxel;and c) administering to the mammal an effective amount of a platinum complex. The method provides unexpected synergistic efficacy. The invention further provides a kit for treatment of a mammalian tumor comprising 3-amino-1,2,4-benzotriazine 1,4-dioxide, paclitaxel and a platinum complex.

Description

TRIPLE COMBINATION FOR TREATMENT D? A TUMOR DESCRIPTION OF THE INVENTION The present invention relates to the field of treatment for cancerous tumors. More specifically, the present invention relates to the treatment of cancerous tumors with tirapazamine, paclitaxel and platinum complex. Tirapazamine is a bio-reducing agent that preferentially eliminates hypoxic cells. Tirapazamine, ie 3-amino-1,2-benzotriazine 1,4-dioxide (SR-4233) has the structural formula When given as multiple injections in conjunction with fractionated irradiation, tirapazamine eliminates hypoxic cells, which increases the elimination of tumor cells while not harming normal tissue in the SCCVII mouse and other tumors as reported by: Brown, JM, Potentiation by the hypoxic cytotoxin SR 4233 of cell killing produced by fractionated irradiation of mouse tumors, Cancer Res. 50: 7745-7749 (1990) and Brown, J.M. et al, SR 4233: A tumor specific radiosensitizer active in fractionated radiation region, Radiother, and Oncol. , 20 * 151-156 (1991). Brown has considered that tumor hypoxia may actually be a therapeutic advantage when combined with a hypoxic cytotoxin such as tirapazamine with fractionated irradiation: Brown, J. M. et al., Tumor hypoxia: the picture has changed in the 1990s, Int. J. Radia t. Biol. , 65: 95-102 (1994); and Brown, J. M. et al, Therapeutic advantage of hypoxic cells in tumors: a theoretical study, J. Nat. Can Inst., 83: 178-185 (1991). International Application No. PCT / US89 / 01037 discloses 1, 2, 4-benzotriazine oxides as radiosensitizers and selective cytotoxic agents. Related patents include: Patent of the United States. 5,175,287 which describes the use of 1,2,4-benzotriazine oxide in conjunction with radiation for the treatment of tumors. The oxides of 1, 2, -benzotriazine sensitize tumor cells to radiation and make them more conducive to this treatment modality. U.S. Patent Nos. 3,868,372 and 4,001,410 which describe the preparation of 1, 2, 4-benzotriazine oxides; and U.S. Patent Nos. 3,991.18.9 and 3,957,799 which describe 1, 2, 4-benzotriazine oxide derivatives. Paclitaxel is a natural product with antitumor activity. The chemical name for paclitaxel is 5β, 20-epoxy-1, 2a, 4, 7β, lOß, 13a-hexahydroxy-11-in 9-one 4,10-diacetate 2-benzoate 13 ester with (2R, 3S) -N- benzoyl-3-phenylisoserine. Paclitaxel has the following structural formula: Paclitaxel is a pale white to white crystalline powder with the empirical formula C4H5i O? 4 and molecular weight of 853.9. It is highly lipophilic, insoluble in water, and melts around 216-217 ° C. Paclitaxel is an antimicrotubular agent that promotes the assembly of microtubes from tubulin dimers and stabilizes the microtubules avoiding depolymerization. This stability results in the inhibition of the normal dynamic reorganization of the microtubule network that is essential for the vital interface and the mitotic cellular functions. In addition, paclitaxel induces abnormal clusters or "clusters" of microtubules through the cell cycle and multiple microtubule asters during mitosis. Cisplatin is a platinum coordination complex that is used as a chemotherapeutic agent against cancer. Cisplatin, that is, cis-diaminedichloroplatinum, has a central platinum atom surrounded by two chlorine atoms and two molecules of ammonia in the cis position and the structural formula: NH3. ^ Cl NE ^ ^ Cl It is a white powder (m.p. ~ 207 ° C) with the molecular formula PtCl2H6N2 and having a molecular weight of 300.1. This is soluble in water or saline at 1 mg / mL and in dimethylformamide at 2.4 mg / mL. Due to their chemical structure, the chlorine atoms of cisplatin are more subject to chemical shift reactions by nucleophiles, such as water or sulfhydryl groups, than to catalyzed enzyme metabolism. Corboplatin is a platinum coordination compound that is used as a chemotherapeutic agent against cancer. The chemical name for carboplatin is, diamine [1, l-cyclobutane-dicarboxylate (2) -0,0 '] -, (SP-4-2). Carboplatin has the following structural formula: Carboplatin is a crystalline powder with the molecular formula CeH? 2N204Pt and a molecular weight of 371.25. It is soluble in water at a rate of approximately 14 mg / mL, and the pH of a 1% solution is 5-7. It is virtually insoluble in ethanol, acetone and dimethylacetamide. Carboplatin, like cisplatin, produces DNA cross-linking predominantly between strains instead of DNA-protein cross-linking. This effect is apparent non-specific cell cycle. The introduction into water of carboplatin that is thought to produce the active species occurs at a lower rate than in the case of cisplatin. Despite this difference, it appears that both carboplatin and cisplatin induce equal numbers of drug-DNA reticulate, causing equivalent lesions and biological effects. The differences in potency of carboplatin and cisplatin appear to be directly related to the difference in immersion rates in water. Another platinum complex that has shown clinical promise is oxaliplatin. Oxaliplatin, that is, cis-oxalate (trans-1-1, 2-cyclohexanediamine) platinum (II) having the structure: is described in U.S. Pat. No. 4,169,846. Related patents include: Patent of United States 5,290,961; United States Patent ,298,642; U.S. Patent 5,338,874; U.S. Patent 5,420,319 and PCT / IB / 00614. Holden et al. (1992) "Enhancement of Alkylating Agent Activity by SR-4233 in Fusion Murine Fibrosarcoma" JNCI 84: 187-193 describes the use of SR-4233, also known as tirapazamine, in combination with an antitumor alkylating agent. The four antitumor alkylation agents, cisplatin, cyclophosphamide, carmustine and melphalan, were each tested to examine the ability of tirapazamine to overcome the resistance of hypoxic tumor cells to antitumor alkylating agents. Tirapazamine was tested alone and in combination with various amounts of each of the antitumor alkylating agents. When SR-4233 was administered just before individual dose treatment with cyclophosphamide, carmustine or melphalan the marked dose was improved leading to synergistic cytotoxic effects on the tumor cells that were observed. When SR-4233 was administered just before treatment with single dose of cisplatin, however, dose improvement led to an additive effect, except at the highest dose level of cisplatin. Brown, U.S. Patent No. 5,484,612 describes the treatment of tumor cells with combinations of chemotherapy agents and 1,2,4-benzotriazine oxides. It has been described that the triple combination of tirapazamine, paclitaxel and a platinum complex unexpectedly provides a greater additive synergistic effect, of efficacy when administered in the treatment of mammary tumors compared in double combinations of these anticancer agents. The present invention provides a method of treating a mammal having a solid tumor. The method comprises: a) administering to the mammal an effective amount of 3-amino-1,2, -benzotriazine 1,4-dioxide; b) administering to the mammal an effective amount of paclitaxel; and c) administering to the mammal an effective amount of platinum complex. The present invention further provides a kit for treating mammalian tumors comprising: 3-amino-1,2,4-benzotriazine 1,4-dioxide; paclitaxel; and a platinum complex. Figures 1 and 2 illustrate the mean tumor weight versus time for treatment methods employing tirapazamine, paclitaxel and a platinum complex as individual agents and in combination. The invention is described in the following particularly in preferred embodiments which exhibit tirapazamine and paclitaxel. In addition, it is contemplated that the invention may be practiced in conjunction with tirapazamine analogs and paclitaxel analogues. Anticancer agents useful in the practice of this invention, for example, tirapazamine, paclitaxel and the platinum complex are known compounds and / or can be prepared by techniques known in the art. In addition to the platinum complexes described herein, it is considered that the invention can be practiced with other platinum complexes. Suitable platinum complexes are described in U.S. Patent No. 5,662,925. Anticarcinogenic agents useful in the practice of this invention are administered to the mammal by known conventional routes appropriate for the particular anticancer agent. The anticancer agents described herein may be administered by the same route, or by different routes. For example, anticarcinogenic agents can be administered to patients orally or parenterally * (intravenous, subcutaneous, intramuscular, intraspinal, intraperitoneal, and the like). When administered parenterally the compounds will normally be formulated in a unit dose injectable form (solution, suspension, emulsion) with a pharmaceutically acceptable carrier. Such vehicles are typically non-toxic and non-therapeutic. Examples of such vehicles are water, aqueous vehicles such as saline solution, Ringer's solution, dextrose solution, and Hank's solution and non-aqueous vehicles such as fixed oils (eg, corn, cottonseed, peanut and sesame), ethyl oleate and isopropyl myristate. Sterile saline is a preferred vehicle. The vehicle may contain minor amounts of additives such as substances that improve solubility, isotonicity, and chemical stability, for example, antioxidants, pH regulators and preservatives. When administered orally (or rightly), the compounds will usually be formulated in the unit dosage form such as a tablet, capsule, suppository, or capsule. Such formulations typically include a solid, semi-solid carrier or diluent or carrier liquid or diluent. Exemplary diluents and carriers are lactose, dextrose, sucrose, sorbitol, mannitol, starches, acasia gum, calcium phosphate, mineral oil, cocoa butter, theobroma oil, alginates, tragacanth, gelatin, methylcellulose, polyoxyethylene, sorbitan monolaurate , methyl hydroxybenzoate, propyl hydroxybenzoate, talc and magnesium stearate. In preferred embodiments, anticancer agents are administered intravenously. The anticancer agents useful herein may be administered simultaneously or sequentially. It is considered that the improved efficiency observed does not depend on the administration time. In preferred embodiments, tirapazamine is administered to the mammal from about one hour to about 24 hours prior to the administration of paclitaxel and the platinum complex. Anticancer agents are administered to the mammal in effective amounts to treat susceptible tumors. Such amounts are well known in the art and can be determined by reference, in the case of paclitaxel, cisplatin and carboplatin, to the product literature provided by the supplier. Additionally, the quantities can be determined by reference to the scientific literature. For example, tirapazamine is administered to the mammal in effective amounts to eliminate or produce cytotoxic effects on hypoxic tumor cells. The amount of tirapazamine administered will depend on such factors as the type of cancer tumor, the age and health of the mammal, the maximum tolerated and / or lethal dose and the interaction with other anti-cancer chemotherapeutic agents. In preferred embodiments of the invention, tirapazamine is administered in amounts from about 10 mg / m2 to about 450 mg / m2, more preferably from about 20 mg / m2 to about 350 mg / m2; more preferably from about 30 mg / m2 to about 250 mg / m. "Preferred dosing regimens for tirapazamine include those described in International Application No. PCT / US89 / 04112. In the preferred embodiments, the taxane derivative it can be administered in amounts from about 30 mg / m2 to 300 mg / m2, more preferably from 50 mg / m2 to 250 mg / m2, most preferably from 100 mg / m2 to 200 mg / m2 Paclitaxel is available under the trade name TAXOL in individual dose containers of 30 mg (5mL) Each mL of sterile non-pyrogenic solution contains 6 mg of paclitaxel, 527 mg of Cremophor® El (polyoxylated castor oil) and 49.7% (w / w) dehydrated alcohol, USP This non-aqueous solution is intended for dilution with a suitable parenteral fluid before intravenous infusion Paclitaxel can be diluted with 0.9% Sodium Chloride Injection, USP, 5% Dextrose Injection, UPS, 5% Dextrose and Cl injection Sodium Oruro 0.9%, USP, or 5% Dextrose in Ringers Injection to a final concentration of 0.3-1.2 mg / mL. Preferred dosing regimens for paclitaxel include those described in the 1996 edition of the Edition of the Physicians Desk Reference. In preferred embodiments, the platinum complex can be administered in amounts of about 10 mg / m2 to about 250 mg / m2; more preferably from about 20 mg / m2 to 200 mg / m2; more preferably from about 30 mg / m2 to 180 mg / m2. Oxaliplatin is preferably presented in the form of a frozen dry powder for infusion in containers containing 50 mg or 100 mg of oxaliplatin and 450 mg or 900 mg of lactose monohydrate. Frozen dry powder can be reconstituted by adding 10 to 20 ml (for the 50 mg container) or 20 to 40 ml (for the 100 mg container) of water for injection or 5% glucose solution and then diluting to an infusion solution of 250 ml or 500 ml of 5% glucose. The reconstitution or final dilution should preferably not be carried out with a sodium chloride solution. The oxaliplatin can be introduced intravenously, preferably for a period of up to 4 hours. The currently preferred dosage regimens for oxaliplatin include the administration of repeated doses of oxaliplatin in cycles of 1, 3 and 5 days, the number of cycles varying from 6. The preferred dosage regimens for caxboplatin and cisplatin include those described in the Edition 1996 from the Physicians Desk Reference. Methods and Results Human Lung Tumor Xenograft MV-522 Hairless mice weighing approximately 20g were implanted s.c. by trocar with fragments of human lung carcinomas MV-522 cultured from growing s.c. in mice without beautiful mice. When the tumors were approximately 5mm x 5mm in size, (usually ten days after the inoculation), the animals were grouped in pairs in control and treatment groups. Each group contained 8 mice with tumor, each of which was labeled on the ear and followed individually through the experiment. The administration of drugs or vehicle began the day the animals were grouped in pairs (day 1). Doses, route of drug administration and programming were selected as appropriate for the study. If the MTD dose of an agent was not known, it was determined in an initial dosing experiment in mice without tumors. The mice were weighed twice a week and the tumor measurements were taken by calibrators twice a week, starting on Day 1. Those tumor measurements were converted to the tumor weight in milligrams by a well-known formula, L2 x W /2. The experiment was terminated when the control tumors reached a size of approximately 1 gram. Upon completion, all mice were weighed, sacrificed and the tumors were excised. The tumors were weighed and the mean tumor weight per group was calculated. In those models, the weight of tumor treated medium / weight of control tumor medium x 100% / T / C) was subtracted from 100% to give the inhibition of tumor growth (TGI) for each group. ^ Some drugs caused tumor shrinkage in the model (MV-522) of human lung tumor xenograft. With these agents, the final weight of a given tumor was subtracted from its own weight at the start of treatment on Day 1. This difference divided by the initial weight of the tumor is% shrinkage. An average% tumor shrinkage can be calculated from the mouse data in a group that undergoes tumor regressions. If the MV-522 tumor completely disappeared in a mouse, this was considered as a complete regression or complete shrinkage of the tumor. If desired, mice with partial or total tumor regressions can be kept alive after the termination date to see if they live or become long-term tumor-free survivors.

The study comparing the carboplatin-paclitaxel-tirapazamine regimen with the oxaliplatin-paclitaxel-tirapazamine regimen was conducted in a long controlled experiment involving two hundred mice. The activities of each of these three drugs as individual agents was determined, and the efficiencies of various combinations of three (triple) senses of the agents were also evaluated. A number of mice in this study experienced shrinkage of the tumor at the termination of the experiment. In this report, to facilitate the description of the results, any lung tumor shrinkage between 1% and 99% in the animal was scored as a partial response (PR), and any mouse with complete shrinkage (disappearance) of your neoplasm will be considered as a complete response (CR). The efficiency of the treatment in the rest of the mice will be presented as inhibition values of tumor growth. RESULTS Example 1 Oxaliplatin-paclitaxel-tirapazamine regimen High and low doses of oxaliplatin, paclitaxel and tirapazamine were combined against the MV-522 tumor in all possible triple combinations of the three drugs. Each tiple combination was active. The shrinkage of the tumor occurred at the end of the study in seven of the eight combination groups, only the triple combination of low doses of all three agents did not produce a shrinkage of the tumor. Seven cases of complete tumor shrinkage (CRs) were recorded between the groups in this regimen, and eight cases of partial tumor shrinkage (PRs) were observed. Three CRs were obtained in the group of eight mice treated with low dose oxaliplatin-high doses of paclitaxel-high dose tirapazamine, the highest number of CRs obtained in any group throughout the study. The regimen was well tolerated by the mice. The weight loss on Day 6 (the peak weight day) ranged from 3.2% to 10.7% among the eight groups, and no toxic deaths were recorded in this group of 64 mice. Example 2 Carboplatin, paclitaxel and tirapazamine regimen High and low doses of carboplatin, paclitaxel and tirapazamine were combined in the MV-522 experiment using all possible triple combinations of the three agents. As with the regimen containing oxaliplatin, all triple combinations of the carboplatin regimen were active. Two cases of complete tumor shrinkage (CRs) and six cases of partial tumor shrinkage (PRs) were recorded with this regimen at the end of the study. Another of the eight cases of tumor shrinkage was obtained in the group study. Four of the eight cases of tumor shrinkage were obtained in the group that received high dose of carboplatin, high dose of paclitaxel-low dose of tirapazamine. The carboplatin-containing combinations were well tolerated by the 64 animals that received this regimen. Weight changes varied from a weight gain of 1.7% to a weight loss of 14.9% among the eight groups. A toxic death occurred with this regimen (high dose of carboplatin, low dose of paclitaxel-high dose of tirapazamine). The results described above were confirmed in the following study. Hairless mice weighing approximately 20g were implanted by touching with fragments of human lung carcinomas MV-522 grown from tumors growing s.c. in mice mice without hair. When the tumors were of a size of approximately 5mm x 5mm (usually ten days after inoculation), the animals were grouped in pairs in treatment and control groups. Each group contained eight mice with tumor, each of which was identified in the ear and followed individually throughout the experiment. Tirapazamine was administered three hours before oxaliplatin, carboplatin, and paclitaxel. The route and time for all drugs was qdxl.

The mice were weighed twice a week, and tumor measurements were performed by calibrators twice a week, starting on Day 1. Those tumor measurements were converted to tumor weight in mg by a well-known formula L x W2 / 2. The experiment was terminated when the control tumors reached a size of 1 gram. Upon completion, all mice were weighed, sacrificed and the tumors were excised. The tumors were weighed, and the average tumor weight per group was calculated. In these models, the weight of tumor treated medium / weight of control tumor medium x 100% (T / C) was subtracted from 100% to give the inhibition of tumor growth (TGI) for each group. Some drug combinations caused tumor shrinkage in the human lung tumor xenograft model MV-522. With these agents, the final weight of a given tumor was subtracted from its own weight at the start of treatment on Day 1. This difference divided by the initial weight of the tumor is% shrinkage. An average% tumor shrinkage can be calculated from data from a mouse in the group that underwent tumor regressions. If the MV-522 tumor completely disappeared in a mouse, this was considered as a complete regression or complete tumor shrinkage.

TABLE 1 Carboplaine, Paclitaxel and Tirapazamine vs W1V-522 Xerograft of Human Pulmonary Tumor Carboplatin (8) lOOmg / lcg / i.p. qdxl -15% 5565 ± 1298 39.7 0 - • 0 0 Carboplatin (8) 50ragkgi.p. qdxl -17% 6981 ± 160.5 22.5 0 __ 0 0 Paclitaxel (8) 20mg / ¡.g / i p. qdxl + 04% 5529 ± 68º 40.2 0 - 0 1 Tirapazamine (8) 70mgftg / i.p. qdxl -17% 835.3 ± 1! 1.2 5.7 0 - 0 0 Paclitaxel + (8) 20mg? -g / i.p. qdxl + 2.7% 284.0 ± 5I.8 73.0 0 - 0 0 Tirapaza-mina 70mg / kgi.p. Paclitaxel + (8) 20mgkg¡.p. qdxl -1.3% 2 I4 ± 703 68.8 2 53.0 0 0 Carboplatina lOOragkg / i.p. i- ' Paclitaxel + (8) 20mgkgi.p. qdxl + 1.7% 4740 ± 93.5 49.8 0 - 0 0 Carboplatin 50mgkg / i.p. Tirapazamine + (8) 70-ng / kgi.p. qdx! -38% 6005 ± 856 34.4 0 - 0 0 Carboplatin lOOmg / kg / i.p. Tirapazamine + (8) 70mgkgi.p. qdxl -4.2% 5498 ± 958 40.3 0 - 0 0 Carboplatin 50mg / kgi.p. Carboplatin + (8) lOOmg / kg / i.p. qdxl -2.4% 504 ± 30.9 859 2 77.3 4 0 Paclitaxel + 20mg / kgi.p. Tirapazamine 70mgkg / i.p. Carbo latina ^ (8) 50mgkg / i.p. qdxl + 34% 584 ± 398 61.2 4 54.9 3 0 Paclitaxel + 20mg / kg / i.p. Tirapaza-mina 70mg / kg / i.p RESULTS-EXAMPLE 3 Carboplatin-Tirapazamine-Paclitaxel The results of the large experiment in which carboplatin, paclitaxel and tirapaza ina were tested as individual agents in combinations of two and three vias against the MV-522 tumor are presented in Table 1 and Figure 1. Paclitaxel and tirapazamine were administered as an individual bolus at doses of 20 mg / kg (2/3 MTD) and 70 mg / kg (MTD) respectively. Carboplatin was given as an individual bolus at a dose of 100 mg / kg (MTD) or 50 mg / kg (1/2 MTD). Paclitaxel and carboplatin (100 mg / kg) given as individual agents each caused an inhibition of small tumor growth (TGI) of about 40%. Tirapazamine was not active as an individual agent. The combination paclitaxel-tirapazamine showed good activity, causing a TGI = 73%. The high-dose carboplatin-paclitaxel regimen was even more effective, producing a tumor shrinkage of 53% in two mice, and 68.8% TGI in the rest of the six animals in this group. The combinations of tirapazamine-carboplatin were not more effective than carboplatin alone. The triple combinations of the three drugs were highly effective against the MV-522 carcinoma. The combination of triple drug with high dose carboplatin caused a mean tumor shrinkage of 77.3% in two mice, a complete tumor regression in four mice, and a TGI = 85.9% in the other two animals in this group. The ecotropic regimen with low doses of carboplatin was also highly active, producing three cases of complete tumor shrinkage, four cases with an average tumor shrinkage of 54.7% and a THL of 61.2% in a mouse. A statistical analysis was performed on these data (see Table 2) using the variances stored in the test. There was a strong tendency for the carboplatin of individual agent dose group to obtain statistical significance against the control group (p = 0.075) Paclitaxel is a simple agent that produced a statistically significant antitumor effect compared to the control group (p = 0 .Ú24). A high degree of statistical significance was achieved with tirapazamine-paclitaxel and paclitaxel-carboplatin (100 mg / kg) combination prepared with paclitaxel alone (p = 0.013 in each case). Triple combination with carboplatin given in 100 mg / kg than paclitaxel-carboplatin (100 mg / kg) double combination, with a p-value of 0.059. The triple combination against the double paclitaxel-tirapazamine combination was highly significant at a more active statistical level, with a p-value of 0.007 determined by the comparison of these two groups.

TABLE 2 STATISTICAL LISIS - ARM D? CARBOPLATIN Comparison P-value Carboplatin (100) vs control 0. 075 Paclitaxel vs Control 0. 024 Paclitaxel + Tirapazamine vs Paclitaxel 0. 013 Paclitaxel + Carboplatin (100) vs paclitaxel 0. 013 Paclitaxel + Carboplatin (100) vs Carboplatin (100) 0. 064 Paclitaxel + tirapazamine + Carboplatin (100) vs Paclitaxel + Carboplatin (100) 0. 059 Paclitaxel + Tirapazamine + carboplatin (100) vs 0. 007 Paclitaxel + Tirapazamine A very important finding from this experiment was that all regimens were very well tolerated (Table 1). No group lost more than 4.2% of body weight on Day 6, and only one toxic death was recorded among the 96 mice in the experiment (in the single agent paclitaxel group). Therefore, the triple combinations of these three agents were well tolerated as the drugs given by themselves. The triple combination of paclitaxel and tirapazamine with carboplatin gave doses of 100 mg / kg or 50 mg / kg producing the complete or martial shrinkage of the tumor in six and seven mice respectively of the sixteen treated animals. The oxiliplatin-paclitaxel-tirapazamine regimens tested in the independent experiments were also highly effective. The results were statistically significant to a large extent. Example 4 Oxaliplatin-Tirapazamine-Paclitaxel The results of the initial experiment with oxaliplatin, paclitaxel and tirapazamine administered as single agents or in various combinations of two and three senses against the human pulmonary carcinoma xenograft MV-522 are shown in Table 3 and Figure 2. Paclitaxel and tirapazamine were given in doses of 20 mg / kg and 70 mg / kg respectively (ip; qd x 1). Oxyliplatin was given at 15 mg / kg (MTD). Oxaliplatin and tirapazamine given as individual agents were not active in this test. Paclitaxel alone produced a marginal TGI = 30.9%. The paclitaxel-oxaliplatin combination was more effective than paclitaxel alone (TGI = 5.4%). The combination paclitaxel-tirapazamine was highly effective, producing a tumor shrinkage of medium 29.2% tumor shrinkage between mice and TGI = 73.1% in the other five animals of this group. The triple combination gives unexpectedly impressive results, causing a mean tumor shrink of 72.4% in four mice and TGI = 87.0% in the other four animals in this treatment group.

The stored variances of the test t were also executed on the data from the repeated experiment (Table 4). The difference in efficacy between paclitaxel plus oxaliplatin versus paclitaxel alone demonstrated the statistical significance limit (p = 0.076). In contrast, the difference between the paclitaxel-tirapazamine combination treatment versus the paclitaxel group alone was highly significant (p = 0.005). The triple combination is compared with the effect caused by the paclitaxel-oxaliplatin combination, which was extremely important (p = 0.001). There is no statistically significant difference between the results achieved with the triple combination compared to the combination of paclitaxel-tirapazamine (p = 0.401). As with the case of the first experiment in this study, all groups in the repetition experiment will tolerate all regimens in a good way. No toxic deaths occurred in this experiment, and the loss of body weight was generally minimal (Table 4).

TABLES Oxaliplatin Carboplatin, Paclitaxel and Tirapazamine vs W1V-522 Xerograft of Human Tumor Lung Change Final Weight% of Inhibition Mice and Shrinkage Mice with # of Dose and Route of Weight of Growth Tumor Shrinkage% of Dead Shrinkage Time Group (Day 6)) (ledio + SEIW)) of the Partial Tumor,, Tumor __ Complete Toxics Control (8) Saline i.p. qdxl + 2.2% 791.4 ± 94.0 0.0 0 0 0 Oxaliplatin (8) 15mg / kg / i.p. qdxl + 5.2% 731.5 ± 62.6 8.2 0 0 0 Paclitaxel (8) 20mg / kg i.p. qdxl + 0.9% 570.5 ± 69.3 30.9 0 0 1 Tirapazaraine (8) 70mg kg i.p. qdxl -6.9% 769.1 ± 73.0 2.5 0 0 0 Paclitaxel + (8> 20 g / kg ip qdxl + 1.2% 395.3 ± 43.8 55.4 0 0 0 Oxaliplatip 15mg kg / ip Tirapazamine + (8) 70mg / kg / ip qdxl -9.5% 615.9 ± 68.2 242 0 0 Oxaliplatin 15mg / kg ip Paclitaxel + (8) 20mg kg ip qdxl -150% 189.9 ± 75.2 73.1 29.2 0 0 Tirapazamine 70mg kg ip Oxa! iplatin + (8) 15mg / g ip qdxl -7.9% 107.9 ± 39.O 87.0 72.4 Paditaxel + 20mg / g / ip Tirapazapupa 70p? g / g ip TABLE 4 STATISTICAL ANALYSIS - OX IPLATIN ARM Comparison Value p Oxaliplatine vs control 0.643 Paclitaxel vs Control% 0.113 Paclitaxel + Tirapazamine vs Paclitaxel 0.005 Paclitaxel + Oxaliplatina vs Paclitaxel 0.076 Paclitaxel + Tirapazamine + Oxaliplatin vs Paclitaxel 0.401 + Tirapaza ina Paclitaxel + Tirapazamine + Oxaliplatin vs Paclitaxel 0.001 + Oxaliplatin While the applicants do not wish to link to theoretical mechanisms, it is noted that the purposes of the scientific literature differ from the molecular mechanisms of action for tirapazamine, paclitaxel and platinum complexes. The different mechanisms of action can in part lead to the observed synergistic efficacy. It is therefore contemplated that the tirapazamine analogs and paclitaxel analogs may also provide the improved efficiency observed herein. Suitable tirapazamine analogs can be selected from those described in International Application PCT / US89 / 04112. Suitable analogs of paclitaxel include taxane derivatives, such as docetaxel and other analogs described in U.S. Patent No. 4, 81, 70 and U.S. Patent No. 5,403,858. Having described the invention with reference to its preferred embodiments, it is understood that modifications within the scope of the invention will be apparent to those skilled in the art.

Claims (10)

1. CLAIMS 1. The use of: a) an effective amount of 3-amino-1,2,4-benzotriazine 1,4-dioxide; b) an effective amount of paclitaxel; and c) an effective amount of a platinum complex to treat a mammal having a solid tumor.
2. 2. The use according to claim 1, characterized in that said platinum complex is selected from the group consisting of oxaliplatin, cisplatin and carboplatin.
3. 3. The use according to claim 1, characterized in that said platinum complex is cisplatin.
4. 4. The use according to claim 1, characterized in that the platinum complex is carboplatin.
5. 5. The use according to claim 1, characterized in that the platinum complex is oxaliplatin.
6. 6. A kit for treating mammalian tumor comprising 3-amino-1,2,4-benzotrizine, 1,4-dioxide, paclitaxel and platinum complex.
7. The equipment according to claim 6, characterized in that said platinum complex is selected from the group consisting of oxaliplatin, cisplatin and carboplatin.
8. 8. The equipment according to claim 6, characterized in that the platinum complex is cisplatin.
9. 9. The equipment according to claim 6, characterized in that the platinum complex is carboplatin.
10. 10. The equipment according to claim 6, characterized in that the platinum complex is oxaliplatin.