IV. Chemotherapy of Tumors in Rats with Piperazine-l,4-bis (N,N'-diethylenephosphondiamide). ∗

Abstract

Summary

1. Piperazine-1, 4-bis(N,N'-die-thylenephosphondiamide) (PDA) in doses up to 1 mg/kg/D for 4-6 weeks produced no significant toxic reaction in rats: at higher doses there was some leukopenia but it was not serious, even with doses of 3.0-4.5 mg/ kg D administered for 4-6 weeks. 2. Flex-ner-Jobling carcinoma regressed completely in 30% of rats treated with .2 mg/kg/D of PDA and in about 90% of those with 3.5 mg/ kg/D. There were no regressions among the controls 34 days after implantation. 3. Growth of sarcoma Rl in Wis tar rats was retarded about 50% by the product at 3 mg/kg/D. 4. Walker 256 carcinosarcoma was retarded in growth by doses of 1-3 mg/ kg/D and inhibited for about 2-3 weeks with a dose of 4.5 mg/kg/D. 5. After initial period of growth inhibition the Walker tumor became resistant to the drug and then grew rapidly in spite of continued therapy.