SOUTH SAN FRANCISCO, Calif., July 2, 2012 /PRNewswire/ -- Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) announced today that the company has begun enrollment in the ENDEAVOR trial, a Phase 3 trial evaluating Kyprolis ™ (proposed brand name for carfilzomib) in combination with dexamethasone, versus bortezomib (Velcade®) with dexamethasone in patients with relapsed multiple myeloma. "The ENDEAVOR trial is the first head-to-head trial conducted with Kyprolis, and is an important step in the development program," said Ted W. Love, M.D., Executive Vice President, Research and Development and Technical Operations at Onyx Pharmaceuticals. "The initiation of this trial underscores our commitment to patients with multiple myeloma who are in need of new treatment options beyond the currently available therapies." The FDA is currently reviewing a New Drug Application (NDA) for potential accelerated approval of Kyprolis in the U.S. for the treatment of patients with relapsed and refractory multiple myeloma who have received at least two prior lines of therapy that included a proteasome inhibitor and an immunomodulatory agent (IMiD). The Prescription Drug User Fee Act (PDUFA) date for completion of the NDA review by the FDA is July 27, 2012. Phase 3 Trial DesignThe ENDEAVOR (Randomiz Ed, Ope N‐Label, Phase 3 Study of Carfilzomib Plus DExameth Asone Vs Bortezomib Plus Dexamethas One in Patients With Relapsed Multiple Myeloma) trial is an 888 patient study evaluating Kyprolis in combination with dexamethasone, versus Velcade® (bortezomib) with dexamethasone in patients whose multiple myeloma has relapsed after at least one, but not more than three prior therapeutic regimens. The primary endpoint of the trial is progression-free survival. Secondary endpoints include overall survival, overall response rate, duration of response, and safety. Patients will be randomized to receive Kyprolis intravenously (20mg/m(2) on days 1 and 2 of cycle 1 only, then 56 mg/m(2) subsequently) with low-dose dexamethasone (20mg), versus bortezomib (1.3 mg/m(2)) with low-dose dexamethasone. Bortezomib can be administered subcutaneously or intravenously at the discretion of the investigator and in accordance with regulatory approval of bortezomib. The study will be conducted at approximately 200 sites worldwide. For information about this study, please visit www.clinicaltrials.gov under trial identification number NCT01568866. About the Kyprolis™ (proposed brand name for carfilzomib) Development ProgramKyprolis is an investigational agent and is not approved by the U.S. Food and Drug Administration (FDA), the European Medicines Agency (EMA) or other health authorities. The NDA submission currently under review by the FDA is based on the Kyprolis 003-A1 study, an open-label, single-arm Phase 2b trial of Kyprolis (20mg/m(2) in cycle 1 and 27mg/m(2) in subsequent cycles), as well as supportive data from additional studies.