The FDA approved the injectable drug Jevtana (cabazitaxel), a microtubule inhibitor, in combination with prednisone as a second-line therapy for men with advanced castrate-resistant prostate cancer (CRPC). Cabazitaxel is indicated for patients whose disease is resistant to docetaxel and standard hormonal treatments. The pivotal trial considered by the FDA demonstrated that cabazitaxel extended survival by ~2.5 months over standard chemotherapy. In a press release, the principal investigator for the North American arm of the trial, Oliver Sartor, MD, Plintz Professor for Cancer Research at Tulane Medical School, New Orleans, said, “Jevtana will help fill a critical treatment gap, since it is the first treatment approved for patients with this stage of metastatic hormone-refractory prostate cancer.”
Sartor, a lead investigator for the multinational phase III TROPIC study, presented data on cabazitaxel at the 2010 American Society of Clinical Oncology meeting in Chicago, Illinois. TROPIC randomized 755 men with metastatic CRPC who failed on docetaxel chemotherapy to cabazitaxel (n = 378) or mitoxantrone (n = 377). Both cohorts received treatment every 3 weeks for 10 cycles, as well as 10 mg of prednisone daily.
Patients receiving cabazitaxel experienced a mean survival of 15.1 months compared with 12.7 months for the mitoxantrone arm (hazard ratio [HR], 0.72; 95% confidence interval [CI], 0.61-0.84). Researchers also found that men in the cabazitaxel cohort had 14.4% tumor shrinkage compared with a 4.4% reduction for those receiving mitoxantrone (P = .0005), although no patients experienced complete response. Further positive data for patients receiving cabazitaxel included a 30% reduction in the risk of death (HR, 0.70; 95% CI, 0.59-0.83; P <.0001).
Approximately 5% of men receiving cabazitaxel suffered treatment-related deaths. Grade 3 or higher neutropenia afflicted almost 82% of men receiving cabazitaxel versus 58% taking mitoxantrone. Leukopenia, anemia, febrile neutropenia, diarrhea, fatigue, and asthenia, were each experienced by at least 5% of patients in the cabazitaxel arm, with renal failure occurring in a small number of patients. Researchers urged proactive monitoring and prompt treatment of all adverse events.