FDA Moves Against Unapproved Obesity Drugs

Last Updated Jan 9, 2009 10:40 AM EST

The FDA has published a list of unapproved, "tainted," or "undeclared" weight-loss drugs that it wants off the market. The list includes rimonabant and sibutramine. Rimonabant was the active ingredient in Zimulti/Acomplia, the ill-fated obesity treatment that Sanofi-Aventis tried to get approved in the U.S. The FDA turned the application down.

UPDATE: Even as the FDA frowns upon obesity drugs, companies keep trying. Galapagos entered a €1.5 million deal with Merck to explore new obesity drug candidates, even though Merck's last obesity candidate, taranabant, went belly-up. Acomplia was marketed for a while in Europe but the European Medicines Authority yanked the drug over safety concerns.

Sibutramine is the active ingredient in Abbott Labs' Meridia, a prescription product. The FDA is not asking that Meridia be removed from the market. Rather, it wants unapproved products that use Meridia as an ingredient pulled. People with hypertension, coronary artery disease, gluacoma, seizures or who are taking certain medicines such as sumatriptan should not take Meridia.

Sibutramine is used in dubious "herbal" pills such as 2 Day Diet, Imelda Perfect Slim and 7 Day Herbal Slim. The brand names sound obscure until you Google them, when it becomes clear there's a huge industry of quacks selling weight-loss cures.

The FDA has also frowned upon the legit Rx obesity pill business. It rejected Orexigen's Contrave pill on Thursday because there was not enough difference between the placebo group and patients actually taking the pill. (The FDA has a standard of 5 percent more weight loss for patients taking the active ingredient; Contrave produced only a 4.2 percent difference.)

Despite the headwinds, companies are still trying. Vivus is hoping the FDA will approve its Qnexa pill, and Arena has lorcaserin hydrochloride in phase 3 trials. Wyeth in December paid $120 million to Thiakis to obtain its anti-obesity drug candidate, TKS1225. Here's a list of some of the industry's big failures and money-losers: