A comparative investigation of the antineoplastic activity of adriamycin and its derivative, N-trifluoroacetyladriamycin-14-valerate (AD 32), was conducted in murine tumor models employing different treatment schedules and injection routes. In all conditions tested, ie, ascitic and disseminated L1210 leukemia, ascitic LSTRA lymphoma, and advanced Lewis lung carcinoma, AD 32 was significantly more effective in terms of lifespan prolongation and induction of cures than optimal adriamycin treatments. As with adriamycin, AD 32 was ineffective on ic transplanted L1210 leukemia.