Orexigen® Therapeutics, Inc. (Nasdaq: OREX) announced today that following a recent meeting with senior officials in FDA's Office of New Drugs (OND), the Company received written correspondence detailing OND's design requirements for a cardiovascular outcomes trial (CVOT) for Contrave® that would address the Complete Response Letter (CRL) received in January 2011.
Orexigen believes that these design requirements are reasonable and feasible and provide the certainty required to reinitiate development of Contrave. Importantly, FDA stated that "if the interim analysis meets the specified criteria to exclude an unacceptable increased cardiovascular (CV) risk, the drug could be approved." Furthermore, FDA stated that "While we still plan to convene a public advisory committee meeting to discuss topics related to obesity drug development early next year, that meeting will not impact on the advice provided in this letter and the agency will honor the advice provided."
"We have been working with clinical experts, advocacy groups, and our partner, Takeda, throughout this process and are pleased with the feedback provided by FDA that identified a very clear and feasible path forward for this important therapy," said Michael Narachi, President and CEO of Orexigen.
The most important aspects of the CVOT design outlined by FDA include that the trial be powered based on an intent-to-treat analysis, along with criteria for interpreting the results at interim and final analyses that are similar to those that are applied to diabetes drugs. Specifically, FDA advised that the trial enroll a population of overweight and obese patients with an estimated background rate of 1.0-1.5% annual risk of major CV events. In this population, the upper bound of the 95% confidence interval should exclude a hazard ratio of 2.0 and 1.4 at the interim and final analyses, respectively. Both FDA and Orexigen estimate that such a study would require approximately 87 total events by the interim analysis to enable resubmission of the NDA for approval. Orexigen estimates that the entire study would require less than 10,000 patients and less than two years from study start to the interim analysis. The Company plans to meet with the review division to finalize a protocol with the objective of initiating the CVOT in the first half of 2012, with potential approval in 2014.
Based on this new feedback from FDA outlining a clear and feasible path forward for Contrave, the Company's three near-term priorities for the program are to: (1) finalize the trial protocol with FDA; (2) re-engage with parties that expressed interest in partnering the ex-North American markets for Contrave; and (3) implement the CVOT as soon as it is able.
"In my experience, Contrave demonstrated great potential for the treatment of obesity in a broad range of patients," said Ken Fujioka, MD, director of the Nutrition and Metabolic Research Center and The Center for Weight Management at the Scripps Clinic, and investigator for the Contrave Obesity Research Program. "On behalf of those working hard to address this significant unmet need, I am pleased to see that a pragmatic approach to bringing this therapy to market appears to be taking shape."
Orexigen management will host a conference call and webcast to discuss this update today at 4:30 p.m. Eastern time. The live call may be accessed by phone by calling (866) 730-5763 (domestic) or (857) 350-1587 (international), participant code 66064656. The webcast can be accessed live on the investor relations section of the Orexigen web site at www.orexigen.com and will be archived for 14 days following the call.
Contrave, an investigational combination therapy of naltrexone HCl and bupropion HCl, was studied for its ability to help people with obesity initiate and sustain weight loss of at least 5 percent of their starting body weight in one year. Contrave was submitted for U.S. regulatory approval in March 2010. The original submission was based on multiple clinical trials that evaluated Contrave in more than 4500 patients. Orexigen received a Complete Response letter from FDA on January 31, 2011.
About Orexigen Therapeutics
Orexigen Therapeutics, Inc. is a biopharmaceutical company focused on the treatment of obesity. Contrave has completed Phase 3 clinical trials, and the Company's other product candidate, Empatic, has completed Phase 2 clinical trials. Each of the components of the Company's product candidates has already received regulatory approval and has been commercialized previously. Further information about the Company can be found at www.orexigen.com.
SOURCE Orexigen Therapeutics, Inc.