COMPLETE TITLE: Phase III, randomized, double-blind, multicenter trial comparing orteronel (TAK-700) plus prednisone with placebo plus prednisone in patients with metastatic castration-resistant prostate cancer that has progressed during or after docetaxel-based therapy: ELM-PC 5
PURPOSE: Orteronel (TAK-700) is an investigational, nonsteroidal, reversible, selective 17,20-lyase inhibitor. This study examined orteronel in patients with metastatic castration-resistant prostate cancer that progressed after docetaxel therapy.
PATIENTS AND METHODS: In our study, 1,099 men were randomly assigned in a 2:1 schedule to receive orteronel 400 mg plus prednisone 5 mg twice daily or placebo plus prednisone 5 mg twice daily, stratified by region (Europe, North America [NA], and non-Europe/NA) and Brief Pain Inventory-Short Form worst pain score. Primary end point was overall survival (OS). Key secondary end points (radiographic progression-free survival [rPFS], ≥ 50% decrease of prostate-specific antigen [PSA50], and pain response at 12 weeks) were to undergo statistical testing only if the primary end point analysis was significant.
RESULTS: The study was unblinded after crossing a prespecified OS futility boundary. The median OS was 17.0 months versus 15.2 months with orteronel-prednisone versus placebo-prednisone (hazard ratio [HR], 0.886; 95% CI, 0.739 to 1.062; P = .190). Improved rPFS was observed with orteronel-prednisone (median, 8.3 v 5.7 months; HR, 0.760; 95% CI, 0.653 to 0.885; P < .001). Orteronel-prednisone showed advantages over placebo-prednisone in PSA50 rate (25% v 10%, P < .001) and time to PSA progression (median, 5.5 v 2.9 months, P < .001) but not pain response rate (12% v 9%; P = .128). Adverse events (all grades) were generally more frequent with orteronel-prednisone, including nausea (42% v 26%), vomiting (36% v 17%), fatigue (29% v 23%), and increased amylase (14% v 2%).
CONCLUSION: Our study did not meet the primary end point of OS. Longer rPFS and a higher PSA50 rate with orteronel-prednisone indicate antitumor activity.
Fizazi K, Jones R, Oudard S, Efstathiou E, Saad F, de Wit R, De Bono J, Cruz FM, Fountzilas G, Ulys A, Carcano F, Agarwal N, Agus D, Bellmunt J, Petrylak DP, Lee SY, Webb IJ, Tejura B, Borgstein N, Dreicer R. Are you the author?
Institution(s): See publishing journal.
Reference: J Clin Oncol. 2015 Mar 1;33(7):723-31.