A total of 25 patients with metastatic breast cancer who had failed one prior chemotherapy regimen and had not received prior treatment with doxorubicin were treated with menogaril (200 mg/m2 i.v. over 1 h) every 4 weeks. Four patients (16%) achieved partial regressions lasting a median of 46 days. The median time to progression for all patients was 60 days and the median survival was 264 days. Seventeen patients subsequently received doxorubicin after removal from protocol and six (35%) achieved objective regression. We conclude that menogaril administered by the method that we employed has marginal activity in women with metastatic breast cancer after failure of prior chemotherapy. Failure to respond to menogaril does not preclude response to subsequent treatment with doxorubicin.