Lenalidomide (Revlimid) failed to improve survival and increased toxicity when added to docetaxel and prednisone in men with chemotherapy-naive, progressive, metastatic castration-resistant prostate cancer in the phase III MAINSAIL trial reported at the 2012 ESMO Congress in Vienna. This study joins several others failing to show benefit when another agent is added to docetaxel in this setting.

“Lenalidomide did not improve overall survival, and the three-drug regimen caused more toxicity. Docetaxel every 3 weeks remains the standard of care for metastatic castration-resistant prostate cancer,” stated lead author Daniel Petrylak, MD, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York.

Study Details

MAINSAIL was an international, multicenter, randomized, double-blind, placebo-controlled trial of first-line treatment for metastatic castration-resistant prostate cancer. Patients with progressive disease were randomly assigned to lenalidomide plus docetaxel/prednisone or docetaxel/prednisone alone. Treatment cycles were repeated every 21 days until disease progression, and patients were followed for 5 years.

Median overall survival was 19.25 months. Progression-free survival was similar between the two arms, with a 1-week difference that favored docetaxel/prednisone (46 vs 45 weeks). Declines in prostate-specific antigen level were similar in both arms, and the objective response rate was about 25% in both arms.

Toxicity was greater with lenalidomide; in particular, diarrhea was more frequent in the lenalidomide-containing arm. ■

Disclosure: Dr. Petrylak reported no potential conflicts of interest.

Reference

1. Petrylak DP, Fizazi K, Sternberg CN, et al: A Phase 3 study to evaluate the efficacy and safety of docetaxel and prednisone with or without lenalidomide in patients with castrate-resistant prostate cancer (CRPC): The MAINSAIL trial. 2012 ESMO Congress. Abstract LBA24. Presented September 30, 2012.