Description
A potent, specific P-gp inhibitor with Kd of 5.1nM; potentiates the cytotoxicity of several drugs including doxorubicin, paclitaxel, etoposide, and vincristine in a panel of human MDR cell lines at 25-80nM; exhibits potent i.v. and p. O. activity without apparently enhancing the plasma pharmacokinetics of paclitaxel or the toxicity of coadministered drugs. Breast Cancer Phase 2 Discontinued