Toxicological Studies on L-Asparaginase

Toxicological and teratological studies on L-asparaginase(KW-020) were performed. The results are summarized as follows. 1. Acute toxicity LD_50 of KW-020 given by various routes to mice, rats, rabbits and guinea pigs is shown in Table-2. 2. Subacute and Chronic toxicity KW-020 was administered to dogs, rabbits, guinea pigs and rats according to the programme described in Table-1. The peak of death by poisoning in all species was observed within 2 weeks of treatment. Overt signs of KW-020 treatment were mainly restraint of weight gain, decrease of food consumption, nausea, diarrhea and hypersensibility at high dose levels in all species. On hematological examination, there were observed decreasing in lymphocyte, serum protein, alkaline phosphatase, serum Ca and increasesing in BUN, NPN at high dose levels in all species. On pathohistological examination, there were observed fatty deposition in liver cell except for dogs and observed the change of reticulum cell in spleen and thymus without dose response relation in all species.