September 11th, 2014
FDA Approves New Weight Loss Drug
The FDA announced today that it had approved Contrave, the long-awaited and much-disputed weight loss drug. Contrave is a combination of two drugs already approved for other indications: naltrexone hydrochloride, which is used to combat alcohol and opioid dependence, and bupropion, which is used to treat depression and seasonal affective disorder and as an aid to smoking cessation treatment. Contrave is manufactured by Orexigen and will be distributed by Takeda.
The FDA said that Contrave had been approved for use in obese adults (BMI of 30 or over) or overweight adults (BMI of 27 or over) with at least one weight-related condition such as high blood pressure, type 2 diabetes, or elevated cholesterol.
The approval comes several years after the approval in 2012 of two competing weight loss drugs, Arena’s Belviq and Vivus’s Qsymia. Neither drug has achieved much success in the marketplace. Orexigen had originally hoped for an even earlier approval but its hopes were dashed in 2011 when the FDA demanded that the company perform a safety study.
In one clinical trial, significant weight loss — defined as the loss of at least 5% of body weight — was achieved by 42% of people who received Contrave and 17% of people who received placebo. In a trial of people with type 2 diabetes, 36% of patients taking Contrave and 18% of patients taking placebo had a significant weight loss.
The FDA said that people taking Contrave should be evaluated after 12 weeks of treatment. Patients who have failed to lose at least 5% of their body weight should discontinue the drug.
Because Contrave contains buproprion, the label will include a boxed warning alerting physicians and patients to the increased risk of of suicidal thoughts and behaviors associated with antidepressant drugs.
The drug can also cause seizures and is contraindicated in people with seizure disorders. Contrave has also been found to increase blood pressure and should not be used in people with uncontrolled hypertension.
The FDA is requiring Orexigen to perform a cardiovascular outcomes trial and two safety and efficacy trials in pediatric populations.