The FDA has been tough on diet drugs of late. Three years ago, it scuttled an attempt to get the European diet drug rimonabant approved for use in the US. More recently it rejected, at least temporarily, applications for Qnexa and Lorcaserin.
But that trend may have been reversed last week, when an advisory committee set the stage for possible FDA approval of Orexigen’s investigational diet drug, Contrave. By a 13-7 vote, the committee said in essence that the somewhat modest beneficial effects of the drug outweighed its tendency to increase blood pressure.
The FDA will make final decision on the matter by the end of January. It is not required to follow the advice of its advisory committees, but as was the case for the 3 diet drugs mentioned above, it usually does.
Orexigen has petitioned the FDA to approve Contrave for the treatment of obesity and weight management in people who have a body mass index of at least 30, or at least 27 if they have at least one cardiovascular disease risk factor like diabetes, high cholesterol or high blood pressure.
Contrave is a combination of 2 drugs that were approved long-ago by the FDA and are widely used today. Naltrexone, the first of these, is used to treat opioid addiction and alcohol dependence. The second, bupropion, is used to treat depression and as a quit-smoking aide.
Before reaching its verdict, the FDA’s Endocrine and Metabolic Drugs Advisory Committee reviewed the results of 4 randomized trials that were sponsored by Orexigen. Together, the studies enrolled more than 4,500 overweight and obese subjects. The Committee noted that in pooled results from the 4 trials, the weight-loss difference between those receiving Contrave and those receiving a placebo was about 4.2%, which it deemed to be “of nominal statistical significance.” However, more than a third of subjects in the Contrave group did lose least 5% of their body weight during a 1-year follow-up period.
“As far as efficacy goes, I think they made it by the hair of their chinny chin chin,” Melanie Coffin, a patient representative on the Committee told ABC News.
The Committee did raise concerns about several side effects of Contrave, including seizures and suicidal ideation, although it was clearly most concerned about the drug’s tendency to increase blood pressure, a phenomenon that seemed to be most apparent in the first few weeks after the drug was started. Ultimately though, the Committee decided there wasn’t enough data to draw clear conclusions about the cardiovascular risks of Contrave. It did recommend that Orexigen should submit post-market data on the matter, if and when it receives full FDA approval.
Currently, the only anti-obesity drug on the market is Orlistat (also known as Xenical and Alli). Recently, Abbott pulled another one, sibutramine (Meridia) after mounting evidence suggested it was associated with strokes and heart attacks.