Arena Pharmaceutical's anti-obesity pill Belviq was cleared Wednesday for adults who are obese or are overweight with at least one medical complication, such as diabetes or high cholesterol.
The FDA denied approval for Arena's drug in 2010 after scientists raised concerns about tumors that developed in animals studied with the drug.
The San Diego company resubmitted the drug with additional data earlier this year, and the FDA said there was little risk of tumors in humans.
With U.S. obesity rates nearing 35 percent of the adult population, many doctors have called on the FDA to approve new weight loss treatments.