Weight Loss Pills rejected by F.D.A. in recent past: Qnexa rejected Thursday

In the recent past FDA or The Food and Drug Administration has rejected many diet pills. Today another weight loss pill has been added to the List.

The rejected drug is Qnexa, developed by Vivus. The third weight loss drug to suffer a significant setback this month because of concerns about safety (like posing risks to the heart or other organs).

Last week, the F.D.A. declined to approve another new drug, lorcaserin, and earlier in the month it forced the withdrawal of Meridia from the market after 13 years, citing the risk of heart attacks and strokes for certain patients.

Supporters of Diet pills or weight loss drugs, mostly from Pharmaceutical industry and those who have found in them a panacea for their obesity, are disappointed by the ruling. Pharmaceutical industry in particular seems to be hard hit, as they considered Qnexa, as one of a few diet pills that represented a new generation of weight-loss drugs, with consumers and pharmaceutical companies pinning their hopes on finding the next best-selling, slimming pill after a decade-long gap in new products. Pharmaceutical industry thinks that such rejections will stall obesity drug research in the country which is facing a massive obesity problem.

With such high profile rejections, only one prescription drug Xenical is now left in the market that is approved for long-term use in managing weight.

The fact that Qnexa produced about twice as much weight loss as other diet pills, including Xenical, is nonetheless disappointing to some specialists as well.

Qnexa is a combination of two existing drugs — phentermine, a stimulant that is approved for short-term use as a weight loss drug, and topiramate, an epilepsy and migraine drug sold by Johnson & Johnson under the name Topamax.


In clinical trials, patients on the highest dose of Qnexa lost an average of 10.6 percent of their weight after one year compared with 1.7 percent for those taking a placebo (a sugar pill a patient takes, believing it to be some real drug. In short a Placebo is nothing but faith.).

Although FDA has not commented or disclosed on how they arrived at 10 to 6 (10 in favor and 6 in oppose) verdict against the drug; the critics of the judgment are saying, among other things, that the F.D.A. appeared to believe that a very effective drug, like Qnexa, would be used so much that unanticipated side effects would show up, while less effective drugs were not worth any risk. In short their plea is that, while drugs with below average performance will stay, those with best results will be culled.

That said, an F.D.A. advisory committee in December will considering another diet drug, called Contrave, developed by Orexigen Therapeutics.