This week Amgen (NASDAQ:AMGN) and its subsidiary Onyx Pharmaceuticals, Inc., announced interim results from a phase 3 clinical trial called ENDEAVOR which is comparing two proteasome inhibitors in 929 patients. The study intended on showing progression-free survival results comparing Kyprolis® (carfilzomib) vs. Velcade® (bortezomib) when combined with dexamethasone. According to release:

Patients with relapsed multiple myeloma treated with Kyprolis lived twice as long without their disease worsening, demonstrating statistically and clinically significant superiority over Velcade (median PFS 18.7 months versus 9.4 months, HR=0.53, 95 percent CI, 0.44 – 0.65).The Kyprolis combination demonstrated superiority over the Velcade combination for secondary objectives of higher overall response rate and lower neuropathy events. Overall survival data are not yet mature and continue to be monitored.

The number of patients leaving the trial due to side effects and other reasons were comparable in both arms. The rates of cardiac failure and renal failure for Kyprolis were comparable to those observed in the Phase 3 ASPIRE study. In ENDEAVOR, the rates for cardiac and renal failure were higher in the Kyprolis arm versus the Velcade arm. There was an increase in the incidence of hypertension and dyspnea in the Kyprolis arm compared to Velcade and that observed in the ASPIRE study. Full study results will be presented at the upcoming Spring ASCO 2015 Annual Meeting.

“We are excited about the results with Kyprolis in the ENDEAVOR and ASPIRE studies and the potential positive impact for patients with relapsed multiple myeloma,” said Robert A. Bradway, chairman and chief executive officer at Amgen. “As new treatment options become available to patients with relapsed multiple myeloma, comparative trials, like ENDEAVOR, are becoming increasingly important to help physicians make informed decisions about the optimal care for patients,” said Pablo J. Cagnoni, M.D., president, Onyx Pharmaceuticals, Inc. “Demonstrating superiority over Velcade in this head-to-head trial supports our goal of ensuring continued improvement of patient outcomes and potentially establishing Kyprolis as the backbone of therapy for patients with multiple myeloma.”

The ENDEAVOR study is the first of two head-to-head studies for Kyprolis versus Velcade, an established proteasome inhibitor, currently approved to treat multiple myeloma. Carfilzomib was developed by Dr. Craig Crewsof the Crews lab. A full Myeloma Crowd Radio show on his discovery can be found here.