The role of WR-2721 in radiotherapy and/or chemotherapy.

This report summarizes the present status of the proposed use of WR-2721 (S-2-(3-aminopropylamino)-ethylphosphorothioic acid) acid) in radiotherapy and/or chemotherapy. This drug selectively concentrates in normal tissues, both in vivo and in vitro, but is passively absorbed by virtually all of the solid tumors which have been studied. In vivo this drug can increase the resistance to radiation or alkylating agents (nitrogen mustard, cis-platinum, cyclophosphamide, and L-phenylalamine mustard) by factors of up to 3, while leaving the solid tumors to suffer the full effects of either treatment.