Orexigen Therapeutics, Inc.

today announced that the Company has submitted a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for Contrave (naltrexone SR/bupropion SR), its investigational drug for the treatment of obesity.

The NDA is based on a substantial body of evidence gathered through the Contrave Obesity Research (COR) clinical program, which included over 4,500 patients.

"The COR program was designed to address all the elements of the FDA guidance for weight loss and weight maintenance in patients with obesity. We believe that if approved, Contrave has the potential to serve the diverse needs of obese patients who currently have few treatment options," said Mike Narachi, President and CEO of Orexigen. "I want to extend my appreciation to the Orexigen team as well as the investigators and patients who participated in the COR program, which provided the high quality data supporting the submission."

Below are highlights from the COR program reported previously:
-- Contrave clearly met the FDA efficacy benchmark: 48% and 56% of
patients on Contrave 32 lost at least 5% of their body weight in COR-I
and COR-II on an intent-to-treat basis, as compared to 16% and 18% of
placebo patients who lost at least 5%, respectively (p<0.001).

-- Significant improvements were observed in cardiometabolic risk factors
such as waist circumference, visceral fat, C-reactive protein, HDL
cholesterol and triglycerides.

-- In the COR-Diabetes trial, patients with type 2 diabetes experienced
significant weight loss and demonstrated meaningful reductions in
HBA1c. Specifically, 45% of patients on Contrave32 lost at least 5% of
their body weight on an intent-to-treat basis, compared to 19% of
patients on placebo (p<0.001). Contrave patients also showed a 0.6%
reduction in hemoglobin A1c (HbA1c) from baseline, compared to a 0.1%
reduction in placebo (p<0.001).

-- Patients treated with Contrave demonstrated statistically significant
improvement in quality of life, and in self reported exploratory
measures of control of eating.

The safety profile of Contrave was found to be consistent with the safety of the two approved active ingredients. The most common adverse reactions (greater than or equal to 5% and at least twice the incidence of placebo patients) were nausea, constipation, vomiting, dizziness and dry mouth. Serious events were reported infrequently and included events of cholecystitis (NB 0.2%, PBO <0.1%), seizure (NB <0.1%, PBO 0%), and major cardiovascular events (NB <0.1%, PBO <0.1%).
"Having achieved this important milestone, we can now focus for the remainder of 2010 on managing the review and approval process for Contrave with the FDA, preparing for the launch of Contrave, and partnership," said Mike Narachi.

About the COR Phase 3 Program

All four trials in the COR Phase 3 program (COR-I, COR-II, COR-BMOD and COR- Diabetes) were randomized, double-blind, placebo-controlled trials, including a four week titration period. The co-primary endpoints were the proportion of patients achieving at least 5% weight loss and percent change in body weight compared to placebo. These endpoints were calculated based on intent-to-treat (ITT) last observation carried forward (LOCF) analyses of all randomized patients who had at least one post-baseline observation while on study drug. Secondary endpoints included multiple measures of cardiometabolic risk, quality of life, and control of eating, as well as HbA1c in the COR-Diabetes trial.