FDA Rejects Both Lorcaserin and Qnexa as Medical Weight Loss Treatments

It does not appear that obesity will be cured by a pill any time soon. Two of the three most recently introduced weight loss pills have been rejected by the US Food and Drug Administration, including lorcaserin (Arena Pharmaceuticals) and Qnexa (Vivus Inc) this month. Meridia by Abbott Labs was pulled from the shelves in October as well. Unless Contrave (Orexigen) is approved in December, the only available prescription medication for is Roche’s Xenical.

Weight Loss Drugs Have Many Side Effects, but Fewer Benefits

The FDA rejected Qnexa, a combination of phentermine and topiramate, yesterday due to safety concerns. An advisory panel voted against approving the drug back in July. Vivus has stated that the agency requested that the company provide a thorough evaluation of the drug’s potential for causing birth defects and heart problems. They have said that they will provide this information to the FDA in about six weeks.

Lorcaserin, an investigational selective serotonin 2C receptor agonist, was not approved because of concerns that it caused mammary tumors in rats. In September, an FDA committee voted 9 to 5 against recommending the drug due to side effects such as depression and memory loss.

Meridia (sibutramine) was recently withdrawn from the market because of the risk of heart attacks and strokes in certain patients. Meridia was initially approved in 1997.

Experts are concerned that the FDA’s recent trend toward rejecting anti-obesity medications will halt drug development from other companies as well. Agency director of the Office of New Drugs, Dr. John Jenkins, says that the FDA is “committed to working toward approval, so long as they are safe and effective for the population for which they are intended.”

As for other medical treatments for obesity, an FDA advisory committee will consider a proposal from Allergan to lower the weight threshold for use of its adjustable gastric banding system, called Lap-Band. Currently, the device is only approved for patients with a BMI greater than 40, or greater than 35 with documented obesity-related health conditions such as diabetes or heart disease.