Orexigen Therapeutics, Inc, a biopharmaceutical company focused on the treatment of central nervous system disorders including obesity, said it has started the fourth trial in its phase III clinical trial programme for its lead product candidate Contrave as a treatment for obesity.
The programme includes a set of four phase III trials evaluating a variety of obesity-related outcome measures, which together are expected to support the New Drug Application (NDA) for review and potential approval of Contrave by the US Food and Drug Administration (FDA).
This clinical trial is a 56-week study intended to assess the safety, tolerability and efficacy of Contrave in generally healthy, nondiabetic, obese patients. A unique aspect of this trial design is the blinded re-randomisation of any Contrave patients who have not responded at week 28 to receive either a higher dose of Contrave or continue on the patient's original dose. The trial will take place at approximately 50 centres nationwide and is expected to enrol approximately 1500 individuals. Patient recruitment for the Contrave trials is now underway.
"Contrave is a unique approach to weight loss that is based on our understanding of the brain as the master regulator of body weight--including appetite, energy expenditure, and the reward-based aspects of eating," said Gary Tollefson, M.D., Ph.D., president and CEO, Orexigen. "With this study, Orexigen hopes to provide clinicians and patients with important information on dosing options in the event of a non-response to an initiation dose. This is the final phase III clinical trial and we are pleased to have initiated each phase III clinical trial on schedule in support of an NDA submission for Contrave in the second half of 2009."
Contrave is a proprietary fixed dose combination of bupropion SR (sustained release) and the company's novel formulation of naltrexone SR in a single tri-layer tablet. Orexigen chose these two constituent drugs based on the results of its model used to screen potential drug combinations and the company's understanding of circuitries in the brain that regulate appetite and energy balance. In a previous phase IIb multi-centre clinical trial, Contrave demonstrated statistically significant weight loss at 24-weeks compared to bupropion SR alone, naltrexone IR (immediate release) alone, and placebo.
In April, Orexigen initiated enrolment in the first of its four phase III clinical trials, a 56-week study designed to evaluate the weight loss potential of Contrave alone or when combined with intense diet, exercise and behaviour modification. This trial is taking place at nine centres nationwide and has completed enrolment.
In May, Orexigen initiated enrolment in its second phase III clinical trial, a 56-week study designed to assess both the safety and efficacy of Contrave in obese subjects who also have been diagnosed with Type II diabetes. Recent studies have demonstrated that obesity is a leading risk factor for various metabolic disorders, such as diabetes, and this trial is designed to evaluate weight loss and factors related to glucose metabolism. The trial is taking place at approximately 50 centres nationwide and is expected to enrol approximately 525 patients.
In October 2007, Orexigen initiated enrolment in its third phase III clinical trial, a 58-week study designed to assess the safety, tolerability and efficacy of Contrave in generally healthy, nondiabetic, obese patients. The trial is designed to take place at approximately 40 centres nationwide and is expected to enrol approximately 1650 patients.
Orexigen Therapeutics, Inc. is a biopharmaceutical company focused on the development of pharmaceutical product candidates for the treatment of central nervous system disorders including obesity. The Orexigen lead combination product candidates targeted for obesity are Contrave, which is in phase III clinical trials, and Empatic, which is in the later stages of Phase II development.