Fixed higher dose schedule of suramin plus hydrocortisone in patients withhormone refractory prostate carcinoma - A multicenter phase II study

BACKGROUND. Using a fixed higher-dose schedule, the efficacy and toxicity o f suramin plus hydrocortisone were assessed in patients with metastatic hor mone-refractory prostate carcinoma (HRPC). METHODS. Fifty consecutive patients with HRPC (including those in whom horm onotherapy was withdrawn) and an Eastern Cooperative Oncology Group perform ance status of 0-2 were recruited. Treatment was comprised of a bolus intra venous infusion of 200 mg of suramin followed by suramin (500 mg/m(2) intra venously [i.v.] over 24 hours) given daily over 5 days as a loading course, followed by suramin (350 mg/m(2) Lv. over 2 hours) administered weekly for 12 weeks. This 12-week course was repeated at 6-month intervals. All patie nts received concomitant hydrocortisone. RESULTS. Five hundred fifty weekly doses of therapy were delivered over the course of the entire study. A partial response, based on a > 50% decrease in the prostate 2 specific antigen (PSA) level, was achieved in 27 patients (54%; 95% confidence interval [95% CI], 44.7-65.0%), 16 of whom (32%; 95% CI, 23.9-43.2%) had a > 75% decrease in their PSA levels. The measurable di sease objective response rate was 18% (95% CI, 2.3-51.8%). Of the 37 patien ts with bone pain requiring analgesia, 27 patients (73%; 95% CI, 55.9-86.2% ) reduced their medication consumption to a lower level on the World Health Organization analgesic ladder. The median duration of response was 15.5 we eks (range, 6-70 weeks), the median time to disease progression was 13 week s, and the median overall survival time was 11 months. Treatment generally was well tolerated. Fatigue and severe lymphopenia were the most commonly r eported significant toxicities. In addition, there was 1 septic toxic death reported, and 10% of the patients were found to have NCI Grade 3-4 neuroto xicity. CONCLUSIONS. The results of the current study demonstrated that the fixed-d ose suramin regimen administered herein showed high, although short-lived, activity and a good tolerance profile in HRPC patients. (C) 2001 American C ancer Society.