Antitumor activity of a new compound, ethyl O-[N-(p-carboxyphenyl)-carbamoyl]-mycophenolate, against various experimental tumors upon oral administration.

: A newly synthesized mycophenolic acid (MPA) derivative, ethyl O-[N-(p-carboxyphenyl)-carbamoyl]-mycophenolate (CAM, NSC-297879D) was tested for antitumor activity, when given orally, against transplantable murine tumors. The compound was markedly effective against transplantable murine tumors. The compound was markedly effective against leukemia P388 and L1210, lymphoma L5178Y, mastocytoma P815 and sarcoma Meth-A, moderately effective against sarcoma-180, C3MC2 and BAMC1, Ehrlich carcinoma, Lewis lung carcinoma and melanoma B16 and marginally effective against hepatoma MH134. The antitumor effects were manifested not only in growth inhibitory effects on subcutaneously transplanted tumors but also in the prolongation of life span of mice int which the tumors had been inoculated intraperitoneally or subcutaneously. The growth of primary transplants of a mammary tumor which developed spontaneously in a C3H/He mouse was inhibited by consecutive administration of CAM frm the 34th day after the transplantation. Oral CAM was more potent than its mother compound, MPA, in the tumor models examined. These results indicate that orally administered CAM has a wide antitumor spectrum.