Mitoxantrone: modest activity in a phase II trial in advanced prostate cancer.

Thirty-seven patients with metastatic prostate cancer refractory to endocrine therapy were treated in a phase II trial of mitoxantrone. Starting doses were 12 and 10 mg/m2 iv every 21 days for good-risk and poor-risk patients, respectively. Of the 35 evaluable patients, two had objective partial regression and five had stable disease. Response duration ranged from 7 to 17+ months. The drug was very well tolerated by these elderly patients; myelosuppression was the major toxic effect. We conclude that mitoxantrone has modest activity and acceptable toxicity in patients with advanced prostate cancer.