FDA to Review New Weight-Loss Drugs

July 7, 2010— -- Drug companies are once again trying to get weight-loss drugs back on the market after a series of high-profile recalls.

On Thursday, the U.S. Food and Drug Administration will review the efficacy and safety of Qnexa, one of three new weight-loss drugs.

Experts hope Qnexa, and the other drugs, Lorcaserin and Contrave, will provide effective weight-loss without the dangerous side effects that doomed other drugs, such as Fen-phen, Meridia and Alli. Fen-phen was pulled from the market in 1997 after it was linked to a thickening of the heart valve. Meridia was pulled from the European drug market in 2009, and the FDA recently warned consumers about Alli's link to severe liver damage.

So far Qnexa has reported positive results.

"It's shown a 10 to 15 percent weight-loss in patients, which is very impressive," said Dr. Ken Fujioka, director of the Scripps Clinic Center for Weight Management in San Diego. He is also on the advisory committee for Vivus, the company that makes Qnexa, as well as on the advisory committees for the companies that make Lorcascerin and Contrave.

Qnexa contains the amphetamine phentermine -- one half the ingredients of the popular combination diet pill Fen-phen, ultimately pulled by Wyeth, its manufacturer in 1997 because of its link to heart damage.

Fujioka said although it proved dangerous in the combination, there were no safety issues with phentermine by itself.

According to Vivus, Inc., the company that makes Qnexa, phentermine helps suppress a person's appetite, while the other ingredient, the anti-convulsant topiramate, makes a person feel more satiated.

Some experts though, questioned the safety of a combination pill that appears to show striking similarities to previously recalled drugs.

"Whether any drug will become another Fen-phen is hard to predict," said Dr. Gerard Mullin, associate professor of medicine at the Johns Hopkins School of Medicine. "Every time we see a drug recalled, none were predictable, but it seems that similar classes of drugs can have inherent problems."