It s been a long, hard road, but after a few years of rejections, Arena Pharmaceuticals weight-loss drug lorcaserin finally won over an FDA advisory panel: They voted 18-to-4 last week in favor of approving the drug. Though the panel s decision is not final, the FDA which will rule on the matter by June 27 usually follows the advisory committee s recommendations.
If approved, lorcaserin would be the first new weight-loss drug to gain FDA approval in over a decade. Previously, it was rejected due to concerns that it was linked to an increased risk of tumors in rodents. Upon further examination, however, the FDA expert panel determined there was no such threat in humans. But while lorcaserin was exonerated from any ties to cancer, some scientists were still concerned that the drug might be associated with valvular heart disease; several panelists even advised that if approved, patients taking lorcaserin should be regularly screened for this condition.
ACSH s Dr. Bloom notes, This precaution is no doubt a reaction to when one of the components of the popular weight loss drug fen-phen was found to cause heart valve damage. Fen-phen was withdrawn from the market in 1997 because the 'fen' component of the drug was found to have heart toxicity. But lorcaserin is a completely new molecule. The fear of similar effects from any drug simply because it promotes weight loss makes no sense scientifically I would be very surprised to see this happen again.
People with a BMI (body mass index) of 30 or more, or those with a BMI of at least 27 who suffer from other obesity-related comorbidities, would be eligible to receive the treatment. In clinical trials, more than twice as many patients who were taking the drug were able to lose at least 5 percent of their total body weight than those taking placebo. This weight-loss improvement is one of the FDA s requirements for approving such drugs. And for some participants, the drug worked even better: Over one-third of patients taking lorcaserin lost 11 percent of their weight, which was equal to, on average, about 25 pounds.
Dr. Domenica Rubino, an endocrinologist and director of the Washington Center for Weight Management, is strongly in favor of approving lorcaserin, stating that We need a broader array of tools, something between cutting calories and cutting the GI tract.
The makers of other weight-loss drugs are also trying their luck, despite the new hurdles placed upon them by the FDA: Qnexa, made by Vivus, gained a positive recommendation from a panel in February and is awaiting a decision from the FDA by July. However, the maker of a third potentially effective drug combo, Contrave, pulled the drug from FDA consideration due to the onerous trial obstacles placed in its path.
ACSH has long griped about the absence of effective weight-loss drugs on the market, which in part has been due to the FDA s overly stringent approval requirements. The agency should be more flexible when it comes to approving such drugs given the vast problem of obesity in our country, says ACSH s Dr. Gilbert Ross.
Dr. Bloom adds, "This recommendation shows signs that the FDA is finally starting to balance the benefits of weight loss with the risks of the therapy."
