Satraplatin is a novel oral
platinum (IV) complex that shows activity against
hormone-refractory
prostate cancer (HRPC) in
cisplatin-resistant human
tumor lines in phase I and phase II trials. A randomized multicenter phase III trial with a target sample size of 380 patients was initiated in men with HRPC. After 50 randomized patients, the trial was closed to further accrual by the sponsoring company. An ad hoc analysis of all available data is reported here. Eligibility criteria included pathological proof of
prostate cancer, documented progression despite prior hormonal manipulation, WHO PS 0-2, and no daily intake of
narcotic analgesics. Patients were randomized between
satraplatin 100 mg/m(2) for 5 days plus
prednisone 10 mg orally BID or
prednisone alone. Compliance was excellent. 48/50 patients have progressed and 42 have died, mostly due to
prostate cancer. Median overall survival was 14.9 months (95% CI: 13.7-28.4) on the
satraplatin plus
prednisone arm and 11.9 months (95% CI: 8.4-23.1) on
prednisone alone (hazard ratio, HR = 0.84, 95% CI: 0.46-1.55). A >50% decrease in prostrate specific
antigen (PSA) was seen in 9/27 (33.3%) in the
satraplatin plus
prednisone arm vs. 2/23 (8.7%) on the
prednisone alone arm. Progression-free survival was 5.2 months (95% CI: 2.8-13.7) on the
satraplatin plus
prednisone arm as compared to 2.5 months (95% CI: 2.1- 4.7) on the
prednisone alone arm (HR = 0.50, 95% CI: 0.28-0.92). This difference is statistically significant (p = 0.023). Toxicity was generally minimal in both arms. This randomized comparison of a combination of
satraplatin and
prednisone versus
prednisone alone supports the antitumor activity of the combination. Its role in the treatment of HPRC remains to be elucidated in an appropriate phase III setting.