Antitumor activity of kijanimicin.

established by the National Cancer Institute'). Kijanimicin, which is water soluble, was dissolved in saline and injected intraperitoneally into tumor bearing mice according to the schedules shown on the accompanying tables. The results of a test in which kijanimicin was administered on three different dose schedules to mice bearing P-388 leukemia are shown in Table 1. The maximum survival increase, T/C= 156, was observed at 32 mg/kg/day on a daily x 9 schedule. Using the same schedule, slight inhibition of B16 melanoma was also seen, Table 2. Two other antibiotics which may be related to kijanimicin, antlermicine•'> and the tetracarcins9.8>, have also been reported to inhibit tumor growth.