Phase II trial of bevacizumab and satraplatin in docetaxel-pretreated metastatic castrate-resistant prostate cancer.

Background: Satraplatin is an oral platinum compound that has demonstrated efficacy and tolerability in prostate cancer. Preclinical synergy between bevacizumab and platinum has been noted.

Methods: Docetaxel-pretreated metastatic castrate-resistant prostate cancer patients with disease progression were eligible. Satraplatin 80 mg/m(2) orally on days 1 to 5, prednisone 5mg twice daily, and bevacizumab 10mg/kg on day 1, and 15 mg/kg on day 15 were administered in 35-day cycles.

Results: Thirty one patients were enrolled. Grade 3 or 4 toxicities were pulmonary embolism in 2 patients and thrombocytopenia in 1 patient. 31% of the patients had a ≥ 30% decline in prostate-specific antigen. Median time to progression was 7.0 months (90% confidence interval [CI] 4.7-8.5mo) and median overall survival was 11.2 months (90% CI 9.1-16.4 mo). Polymorphism in the excision repair cross-complementation-1 (ERCC-1) gene was associated with time to progression (hazard ratio = 1.91). A circulating tumor cell count ≥ 5 was moderately prognostic of overall survival (hazard ratio = 1.49) as compared with CTC <5.

Conclusions: The combination was tolerable, and revealed promising efficacy in metastatic castrate-resistant prostate cancer. ERCC1 genotype maybe predictive of clinical benefit with platinum-based therapy in metastatic prostate cancer.