The study used data from the Mainsail trial, a multinational, randomized phase 3 study of 1,059 patients with mCRPC. In one arm of the study, patients received docetaxel, prednisone, and lenalidomide. These patients had a median of 6 cycles of docetaxel. Patients in the control arm received docetaxel, prednisone, and a placebo. These patients had a median of 8 cycles of docetaxel.
Mainsail was closed early because results showed that the adding lenalidomide led to inferior overall survival and increased toxicity.
However, researchers were able to analyze data from the study and compare the total number of docetaxel cycles given to patients in the two groups. Treatment with 8 or more cycles of docetaxel was associated with better overall survival, regardless of study group. Patients who had more than 10 cycles of docetaxel had a median overall survival of 33 months, compared with 26.9 months for patients treated with 8 to 10 cycles of docetaxel. Patients who received 5 to 7 cycles of docetaxel had a median overall survival of 22.8 months.
The authors said their findings suggest that continuation of docetaxel contributes to a survival benefit, but further prospective validation is warranted.
JAMA Oncol. 2016 Aug 25. doi: 10.1001/jamaoncol.2016.3000. [Epub ahead of print]