Impact of cabazitaxel on 2-year survival and palliation of tumour-related pain in men with metastatic castration-resistant prostate cancer treated in the TROPIC trial

Background Cabazitaxel significantly improves overall survival (OS) versus mitoxantrone in patients with metastatic castration-resistant prostate cancer after docetaxel failure. We examined patient survival at 2 years and tumour-related pain with cabazitaxel versus mitoxantrone. Methods Updated TROPIC data (cut-off 10 March 2010) were used to compare 2-year survival between treatment groups and assess patient demographics and disease characteristics. Factors prognostic for survival ≥2 years were assessed. Pain and Eastern Cooperative Oncology Group performance status were evaluated in the overall patient population. Results Median follow-up was 25.5 months. After 2 years, more patients remained alive following cabazitaxel than mitoxantrone [odds ratio 2.11; 95% confidence interval (CI) 1.33–3.33]. Treatment with cabazitaxel was prognostic for survival ≥2 years. Demographics/baseline characteristics were balanced between treatment arms irrespective of survival. Pain at baseline and pain response were comparable between treatment groups. Average daily pain performance index was lower for cabazitaxel versus mitoxantrone (all cycles; 95% CI –0.27 to –0.01; P = 0.035) and analgesic scores were similar. Grade ≥3 peripheral neuropathies were uncommon and comparable between treatment groups. Conclusions Cabazitaxel prolongs OS at 2 years versus mitoxantrone and has low rates of peripheral neuropathy. Palliation benefits of cabazitaxel were comparable to those of mitoxantrone. The study was registered with www.ClinicalTrials.gov (NCT00417079).