Antitumor spectrum of a new anthracycline, (2"R)-4'-O-tetrahydropyranyladriamycin, and effect on the cellular immune response in mice.

(2''R)-4'-O-Tetrahydropyranyladriamycin (THP), a new anthracycline antibiotic, showed stronger inhibition of the growth of L1210, CCMT (mouse mammary adenocarcinoma) and Yoshida sarcoma in rats than did adriamycin (ADM). The antitumor activity of THP against P388 and Meth-A (mouse fibrosarcoma) was equal or slightly superior to that of ADM. Moreover, THP was active against an ADM-resistant subline of P388. THP at the optimal effective dose against experimental tumors had no toxic effect on the cellular immune system in normal and tumor-bearing mice.