SAN DIEGO, Sept. 20, 2011 /PRNewswire/ -- 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.