Obesity Drug Trials Meet Goals

Photo: e-magic, Flickr

Have the pharmaceutical companies finally found the magic pill for weight loss? While it's not magic, Orexigen Therapeutics Inc. has had positive results in their recent trials for Contrave, a new obesity drug.

In one trial, 48 percent of obese participants who took a higher dose of Contrave lost at least 5 percent of their body weight; only 16.4 percent of control participants (who were taking a placebo) lost comparable weight. In a second trial, 56.3 percent of those taking Contrave lost weight compared to 17.1 percent taking a placebo.

With a more than 7 percent difference between Contrave takers and placebo takers, the trials were above the FDA guidelines for weight loss drugs. (FDA guidelines state that there must be at least a 5 percentage point difference.) A lower dose of Contrave also showed positive results in trials.

Instead of blocking fat absorption like Orlistat (found in the over-the-counter drug Alli) or controlling appetite like Meridia, Contrave tackles weight loss from another direction. Contrave is a combination of Wellbutrin, a common antidepressant, and naltrexone, a medication used to treat addictions.

Existing weight loss drugs have some nasty side effects. Fat blockers, for example, can cause diarrhea and/or anal leakage. Orexigen states that Contrave was generally well tolerated by trial participants. However, possible side effects include gall bladder inflammation and seizures.

Orexigen plans to seek FDA approval for Contrave next year.