A Food and Drug Administration panel Tuesday recommended that the agency approve Orexigen Therapeutics Inc.'s weight-loss drug Contrave, making it the first in a group of competitors to get a nod from experts.

The panel of experts voted 13-7 for Contrave's approval and 11-8, with an abstention, that more studies be done on heart risks. Experts had voiced safety concerns on the drug but found the benefits outweighed the risks. The move marks an about-face on weight-loss drugs after the agency in October rejected Arena Pharmaceuticals' lorcaserin and Vivus Inc.'s Qnexa due to safety.

The FDA is not required to follow the advice of its expert panels, but it often does. The agency is set to make a decision on Contrave by Jan. 31.

FDA scientists are concerned over Contrave's effects on the heart, an issue that has weighed heavy on potential weight-loss drugs. Complaints focused on the company's lack of elderly patients with a history of heart disease in clinical trials. That lack of data made it difficult to determine the drug's safety in patients at risk for heart attack and stroke.

Contrave is a combination pill, mixing the antidepressant bupropion with the anti-addiction drug naltrexone. The FDA reported higher rates of side effects already linked to the drugs, such as high blood pressure, dizziness, and insomnia.

Also, the company didn't meet all the criteria the agency had set for obesity drugs. Studies showed that patients taking the drug, on average, lost 4.2 percent more weight than patients taking a placebo. But, those results did not meet an FDA guideline that there should be at least a 5 percent difference in weight loss between the groups. The drug did meet a second measure of effectiveness involving the number of patients who lost 5 percent or more of their weight.

U.S. obesity rates are near 35 percent among adults, and physicians and new weight-loss therapies are desperately needed. But the search for that treatment has been fraught with safety issues.