Toxicological studies on pepleomycin sulfate (NK631). III. Subacute toxicity of pepleomycin in dogs (author's transl)]

Subacute toxicity and its recovery of pepleomycin sulfate was studied in both sexes of beagle dogs. At dose levels of 2.4, 1.2 and 0.6 mg/kg, pepleomycin was administered intramuscularly to dogs for 30 successive days. Two dogs of the 1.2 mg/kg dose group were used for recovery test for 35 days. As general symptoms, the decrease of food intake, the loss of body weight, ulceration of foot pad, nail root necrosis and onychoptosic, ulcer of tongue and labia, and alopecia, dermatitis and necrosis at friction sites were observed the more severely in high dose groups, as those in bleomycin were. The death occurred in the 2.4 mg/kg dose group of both sexes. The lesions of liver and kidney were recognized in the 2.4 and 1.2 mg/kg dose groups of both sexes on biochemical, histopathological or urinary findings. Additionally slight fibrous change of lung was observed in all dose groups. Generally subacute toxicity of pepleomycin was revealed approximately in the same as or in a little stronger degree than that of bleomycin, and its recovery was hardly recognized during its period. The maximum safety dose in this studies is estimated to be between 0.3 and 0.6 mg/kg in dogs.     

Toxicological studies on pepleomycin sulfate (NK631). VI. Chronic toxicity of pepleomycin in dogs (author's transl)]

Chronic toxicity and its recovery of pepleomycin sulfate was studied in both sexes of beagle dogs. At dose levels of 0.3, 0.15 and 0.075 mg/kg, pepleomycin was administered intramuscularly to dogs for 180 successive days. Two dogs of the 0.15 mg/kg dose group were used for recovery test for 35 days. As general findings, the decrease of food intake, the loss of body weight, ulceration of foot pad, nail root necrosis and onychoptosis, ulcer of tongue and labia, and alopecia, dermatitis and necrosis at friction sites were observed more severely in the 0.3 mg/kg dose group of both sexes, especially in male, than those in bleomycin were. In the dose groups of 0.15 and 0.075 mg/kg, their findings were observed as slightly as those in bleomycin were. The death occurred in the 0.3 mg/kg dose group of both sexes. The lesions of liver and kidney were recognized in the 0.3 mg/kg dose group of both sexes, severely in male, on histopathological findings. Additionally severe fibrosis of lung was observed in one of the 0.3 mg/kg dose group of female. In general chronic toxicity of pepleomycin was revealed more severely in the 0.3 mg/kg dose group than that of bleomycin was, but in the dose groups of 0.15 and 0.075 mg/kg difference between their toxicities was not significant. In addition, chronic toxicity of pepleomycin in dogs showed more severely in male and its recovery was hardly recognized during its period. The maximum safety dose in this studies was estimated to be between 0.075 and 0.15 mg/kg in dogs.     

Toxicological studies on pepleomycin sulfate (NK 631) II. Subacute toxicity of pepleomycin sulfate in rats (author's transl)]

Studies on subactute toxicity and its recovery of pepleomycin sulfate (NK631) were carried out in both sexes of rats. NK 631 was administered intraperitoneally in dose levels of 0.3, 0.9, 2.7. 8.1 and 24.3 mg/kg/day for 30 days. After finishing administration of NK 631 for 30 days, 5 animals of each group were proceeded to recovery test for 35 days. During the course of the experiment, the body weight gains were suppressed in all dose levels except in 0.3 mg/kg group of male rats. The deaths were found in the animals treated with doses over 24.3 mg/kg during treatment period and in those over 2.7 mg/kg during recovery period. In biochemical and urinary analysis, the increases of serum GPT, BUN, Mg, Ca and urine glucose were moderately recognized in 8.1 mg/kg group. Additionally, in macroscopical and histopathological findings, bone damage was found in the animals treated with doses over 2.7 mg/kg during treatment and recovery periods. From these results, the maximum safety dose of NK 631 in subacute toxicity using rats were estimated to be about 0.3 mg/kg.     

Toxicological studies on pepleomycin sulfate (NK631), IV. Chronic toxicity of pepleomycin sulfate in rats (author's transl)]

Studies on chronic toxicity and its recovery of pepleomycin sulfate (NK 631) were carried out in both sexes of rats. NK 631 was administered intraperitoneally in dose levels of 0.15, 0.3, 0.6, 1.2 and 2.4 mg/kg/day for 180 days. After finishing administration of NK 631 for 180 days, animals of each group were proceeded for 35 days recovery test. During the course of the experiment, the body weight gains were suppressed in all dose levels except for 0.15 mg/kg group of female. The deaths were found in all dose levels except for 0.15 mg/kg level of male during treatment and recovery periods. In biochemical and urinary findings, the increase of serum BUN, Mg, inorganic P. and urine glucose were slightly recognized in the animals treated with doses over 0.6 mg/kg. Additionally, in macroscopical and histopathological findings, bone damage and renal lesions were found in the animals treated with doses over 0.6 mg/kg during treatment and recovery periods. From these results, the maximum safety dose of NK 631 in chronic toxicity study using rats were estimated to be at less than 0.15 mg/kg.     

General pharmacological studies on pepleomycin sulfate (NK 631) (author's transl)]

Pharmacological actions of pepleomycin sulfate (NK 631) which is a new antitumor agent derived from bleomycin were studied and the following results were obtained. NK 631 had no significant influences on the central, motor and sensory nervous systems at relatively higher doses (5 approximately 10 mg/kg, i.v., i.p., s.c.). NK 631 (5 approximately 10 mg/kg, i.v.) caused a slight decrease in blood pressure in anesthetized rats and slight increases in blood pressure, heart rate and peripheral blood flow in anesthetized dogs. NK 631 (1 approximately 3 mg) given close-arterially caused a slight increase in the developing tension in the isolated blood-perfused papillary muscle. NK 631 slightly contracted the isolated guinea pig ileum and rat uterus but did not affect the contraction of isolated guinea pig trachea. NK 631 caused significant increases in urine output and Cl excretion in saline loaded rats at 20 mg/kg, i.p. By the local injection of NK 631, a slight edema of rat paw and an increase in rabbit cutaneous permeability were observed. The intraperitoneal injection of NK 631 caused a significant increase in leakage of dye injected intravenously into the peritoneal cavity of mice. NK 631 did not affect hemolysis and prothrombin time at 10(-4) g/ml. In pharmacological actions, significant differences between NK 631 and pepleomycin were not observed.     

Toxicological studies of pepleomycin sulfate. V. Short term intermittent toxicity in dogs (author's transl)]

The comparative studies in the short term intermittent toxicity of pepleomycin (NK631) and bleomycin (BLM) were performed on 10 beagle dogs of 13 approximately 15 months old. Two dogs per group were injected intravenously with NK631 and BLM in doses 5.0 and 2.5 mg/kg body weight every fourth day for 11 treatment. Two dogs served as control and were injected with saline solution. In the group of 5.0 mg/kg of NK631, one dog was sacrificed on day 37 of the treatment and another one dog died on day 33 of the treatment. All the dogs of other group survived until the end of the treatment. The toxicity to the hepatic and renal damage caused by NK631 was stronger than the BLM. On the contrary, the toxicity to lung and various mucocutaneous regions was weaker than the BLM. The grade of pulmonary fibrosis of NK631 was about 1/2 and 2/3 of the BLM in dose of 5 mg/kg and 2.5 mg/kg, respectively. Other toxicological changes such as anorexia and weight loss were almost similar to the BLM.     

Studies on antitumor activities and pulmonary toxicity of pepleomycin sulfate (NK631) (author's transl)]

The antimicrobial and antitumor activities, and the pulmonary toxicity of pepleomycin (NK631) were studied in comparison with bleomycin (BLM). NK631 showed a broad antimicrobial spectrum against gram positive and gram negative bacteria equally to BLM, and its activity was about twice higher than BLM. NK631 showed higher activity on cultured HeLa S3 cells and higher antitumor effect on the transplanted tumors of Ehrlich solid carcinoma in mice, AH66 and AH66F ascites hepatoma in rats, and lower antitumor effect on Ehrlich ascites carcinoma in mice than BLM. Similarly to BLM, NK631 did not show satisfactory activity on L1210 leukemia in mice. NK631 showed marked effect on chemically induced squamous cell carcinoma, spontaneous lymph sarcoma of a dog, human and dog gastric cancer heterotransplanted in nude mice equally to BLM. Furthermore NK631 exhibited remarkably higher antitumor activity on lymph node metastasis of AH66 ascites hepatoma of rats and chemically induced gastric carcinoma of rats than BLM. Pulmonary toxicity of NK631 was low as 1/3 in incidence and 1/4 in grade of the BLM in old mice system. This trend was confirmed by chemical analysis of hydroxyproline in lung.     

Toxicological studies on fosfomycin-Na salt. I. Acute toxicity in mice and rats (author's transl)]

The acute toxicity of sodium fosfomycin (FOM-Na), a new antibiotic in ICR mice and Wistar rats has been investigated. The LD50 values in mice were: 1,230 (male), 1,225 (female) mg/kg by i.v.; 2,175 (m), 2,467 (f) mg/kg by i.p.; 2,625 (m), 2,662 (f) mg/kg by i.m.; 5,100 (m), 6,150 (f) mg/kg by s.c. and 8,020 (m), 7,300 (f) mg/kg by p.o. The LD50 values in rats were: 1,650 (m), 1,560 (f) mg/kg by i.v.; 2,060 (m), 2,000 (f) mg/kg by i.p.; 2,630 (m), 2,460 (f) mg/kg by i.m.; 5,100 (m), 4,320 (f) mg/kg by s.c. and 4,700 (m), 4,550 (f) mg/kg by p.o. Animals dosed only i.v. died within 2 minutes. Signs of toxicity in mice or rats given FOM-Na were similar and included motor activity depression, reduced respiration and occasionally tremors. Surviving mice or rats given FOM-Na developed no pathological changes of the drug specificity.     

Studies on organ distribution, absorption and excretion of pepleomycin sulfate (NK631) (author's transl)]

1. Organ distribution of pepleomycin (NK631) in mice and rats was studied. NK631 was found at higher levels than bleomycin (BLM) in skin, lung, stomach, solid tumor, etc. in mice and rats. Furthermore NK631 was detected in the mesenteric and lumbar lymph node, esophagus and prostate in rats and also distributed at about twice as high levels as BLM in the AH109A hepatoma cell-metastasized lymph nodes. 2. For the elucidation of reason on low pulmonary toxicity of NK631 which is in spite of 1.5 times highly distribution in lung compared with BLM, inactivation of various BLMs by high molecular fraction of lung of mice and rats was determined. The order of inactivation rate of various BLMs in lung was as follows: BLM-M5196 greater than NK631 greater than BLM greater than BLM-HPE. There is an encouraging coincidence between index of pulmonary fibrosis in mice and inactivating rate in lung. 3. A comparative study on the serum level and urinary excretion of NK631 and BLM was performed in dogs. The blood level and urinary excretion rate of both drugs were almost similar. 4. The blood levels of NK631 were comparable to those of BLM in cancer patients.     

Safety evaluation of NK 631. Antigenicity, effect on delated hypersensitivity, irritative effect on eye mucous membrane and mutangenicity of pepleomycin (NK 631) (author's transl)]

1. Whether NK 631 is antigenic to guinea pigs and rabbits was studied by the methods of active and passive anaphylactic shock tests, Schultz-Dale reaction, passive cutaneous anaphylaxis, Ouchterlony, tanned red cell haemagglutination test and test according to the U.S. Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics. However, none of the tests proved NK 631 to be antigenic. 2. The immunosuppressive effect of NK 631 was studied by delayed hypersensitivity to picryl chloride in normal and L-1210 tumor bearing mice. Therapeutic dosis of NK 631 was no immunosuppressed but toxic dosis of NK 631 was slightly decreased in ear thickness of delayed hypersensitivity. 3. The acute irritative effect of NK 631 and of bleomycin was studied by single instillation to the rabbit eye mucous membrane with 0.1 ml of either of 10, 33 and 100 mg/ml solution of the drugs in physiological saline. The irritative effect of NK 631 on the eye mucous membrane at each concentration was slightly severe than that of bleomycin at the same concentration. However, the manifestations were only mild to moderate dilatation of the conjunctival and nictating membrane blood vessels and eye mucous, and recovered or were mitigated 48 hours after the instillation. No severe changes such as corneal opacity, corneal desquamation, swelling and deaquamation of the conjunctival and nictating membrane were observed. The histopathological examination revealed no striking changes. 4. Mutagenicity of NK 631 and of bleomycin on Salmonella typhimurium strain TA 100 and TA 98 was studied. It was definitely shown that neither NK 631 nor bleomycin exerted any mutagenic action on either test strains.     

Toxicological studies on fosfomycin-Na salt. II. Subacute toxicity in rats and rabbits (author's transl)]

FOM-Na solution in distilled water for injection, J.P., with its pH adjusted to 7.0 +/- 0.2 with diluted hydrochloric acid, was administered to rats and rabbits for subacute toxicity test. The results revealed the following: 1. It was intraperitoneally administered to Wistar rats each weighing 100 +/- 10 g at their age of 5 weeks, and intravenously into auricular veins of male albino rabbits each weighing about 3 kg, for 35 successive days except Sundays through one administration per day. There was no death in rats of both sexes with the doses less than 1,000 mg/kg, while 3/10 males and 5/10 females died with the dose of 2,000 mg/kg. In terms of general conditions, both stretched physical position and vocalization were noted, which were presumed to be attributable to the stimuli of the administration. In the postmortem examination mutual adhesion of organs in the peritoneum was noted, while in the lightmicroscopic examinations histological proliferation and adhesion were found out in the hepatic capsules or serous membrane of the intestine etc., but no abnormalities were detected in the other organs. In the mean body weights, there were no significant differences between the control group and the groups of males with doses less than 500 mg/kg and females with doses less than 1,000 mg/kg whereas in the groups of males with doses more than 1,000 mg/kg and the females with a dose of 2,000 mg/kg, a trend of reduced weight gain was noted in comparison with the control group. The feed intake also was reduced as the dose was elevated. In terms of the male group hematology, the In. P increased with doses higher than 250 mg/kg, while BUN was reduced in the groups with a dose of 250 mg/kg and doses higher than 1,000 mg/kg, and Na was reduced in the groups with doses from 125 up to 500 mg/kg. In the female groups, the loss of Hgb and rise in the Cl were noted in the doses higher than 500 mg/kg while the loss of WBC was noted in almost all the treated groups. However, none of these changes was suggestive of specific abnormalities when compared with the photomicroscopic findings and our hematological background data. 2. There were no significant changes in the general conditions of any group of rabbits. Their mean body weights and their mean feed intakes proceeded almost similarly with those of the control group. In the hematological and histopathological tests also, no specific abnormal finding was experienced, which were deemed to be attributable to the administration of FOM-Na.     

Histological appearances of cancer of the head and neck treated with pepleomycin (NK 631) (author's transl)]

Clinical findings and histopathological appearances in the patients with cancer of the head and neck treated with a new anti-tumor agent, pepleomycin, are reported. The total dosage of the new drug was within 100 mg on the average; however, the responses to chemotherapy were considerably favorable in general. Pepleomycin was markedly effective in two patients, moderately effective in seven, and ineffective in one. Microscopic evidences of regression of cancer cells were demonstrated in six surgical materials. Pepleomycin was shown to have an even more selective action on squamous cell carcinoma than bleomycin. The reactions of the surrounding tissue and skin to combination therapy, including pepleomycin, remained comparable to those to bleomycin. Side effects of the drug were slight fever and transient anorexia. No fibrosis of the lung was seen during eight months of observation.     

Clinical effects of NK 631 (pepleomycin) against malignant tumors of the head and neck (author's transl)]

1. The antitumor effect of pepleomycin observed in 11 cases of malignant tumors of the head and neck was compared with that of bleomycin in similar cases, and the former appeared slightly preferable. 2. The adverse reactions to the 2 drugs were similar to each other; however, those to pepleomycin were milder. 3. Only few cases exhibiting such severe pulmonary fibrosis as emphasized in the published data have been encountered in bleomycin treatment in the authors' department. However, with reference to the measurements of PaO2 in the pepleomycin-treated cases, this may be said to be an anticancer drug which is easier to use clinically. 4. Adverse reactions to pepleomycin, e.g., alopecia, malaise, and others, were less frequent and less severe than those to bleomycin. 5. It was studied by the auditory acuity test in 10 cases (excluding 1 dropout) whether any auditory acuity disorder would occur after pepleomycin treatment: No changes in auditory acuity were observed in any of the cases.     

Clinical application of NK 631 to head-and-neck cancers (author's transl)]

NK 631, a new antibiotic of bleomycin analogue, was applied to the treatment of 15 patients with head-and-neck cancers. The results obtained were slightly better than bleomycin-treated cases. For the side effect of NK 631, there were no lung disorders in all patients.