tnp-351 and edatrexate

Two analogues of cytosine arabinoside (ara-C) and three analogues of methotrexate (MTX) are under their clinical studies in Japan. Gemcitabine and DMDC are analogues of ara-C, showing similar antitumor efficacies each other and rather mild animal toxicities. Currently, dFdC is under phase II study, showing activity against lung cancer and DMDC under phase I study. As for MTX analogues, edatrexate, trimetrexate and TNP-351 have been put on the clinical phase studies. Among these antifolates, both edatrexate and trimetrexate have showed responses against lung cancer and we expect that TNP-351 may also show a similar response in the future. Currently, phase II studies of edatrexate and trimetrexate and phase I study of TNP-351 are under progress.

Topics: Aminopterin; Animals; Antimetabolites, Antineoplastic; Antineoplastic Agents; Cytarabine; Deoxycytidine; Humans; Leukemia L1210; Methotrexate; Mice; Trimetrexate

New antifolate antimetabolites are currently developed and three analogues of methotrexate (MTX) (Trimetrexate, Edatrexate, TNP-351) are undergoing clinical trials in Japan. Trimetrexate characteristically enters cells primarily by passive transport, which is different from the mechanism of MTX. The increased therapeutic efficacy of Edatrexate is expected, because of the higher concentration of polyglutamates than MTX in tumor cells. TNP-351 is a novel antifolate, which has a different chemical structure from other antifolates. The current state of clinical trials of three antifolates and the indications for chemotherapy of lung cancer are reviewed.

Topics: Aminopterin; Animals; Antineoplastic Agents; Drug Administration Schedule; Female; Humans; Lung Neoplasms; Male; Methotrexate; Trimetrexate