14-DAY CONTINUOUS-INFUSION OF MITOXANTRONE IN HORMONE-REFRACTORY METASTATIC ADENOCARCINOMA OF THE PROSTATE

A dose-finding investigation was conducted with mitoxantrone administe red as 14-day continuous infusions to patients with hormone-refractory metastatic adenocarcinoma of the prostate. Fifteen men participated i n four dosage groups: mitoxantrone 1.0, 1.25, 1.4, and 1.5 mg/m2/day: a treatment cycle was defined as a dose of mitoxantrone given over 2 w eeks, followed by 2 weeks of monitoring prior to the next course. The patients received 1 to 10 courses, with the majority receiving 1 to 3. The maximum tolerated dose was 1.25 mg/m2/day for 14 days of continuo us infusion. Two patients discontinued treatment because of gastrointe stinal effects. Most adverse clinical experiences were mild or moderat e in intensity. A decrease in prostate-specific antigen (PSA) response was seen after one course in 6 of 14 patients who had PSA measurement s. Stable disease was achieved in 40% of the evaluable patients, and s ome quality of life parameters improved. Further clinical trials with mitoxantrone are indicated in patients with prostatic cancer, especial ly in those who have had less previous treatment.