Shares of San Diego-based Arena Pharmaceuticals Inc. jumped $3.03, or 34 percent, to $11.88 in trading Wednesday afternoon. Arena’s studies showed that patients taking Belviq, known generically as lorcaserin, had modest weight loss.
On average patients lost just 3 to 3.7 percent of their starting body weight over a year. About 47 percent of patients without diabetes lost at least 5 percent of their weight or more, which was enough to meet FDA standards for effectiveness. By comparison, average weight loss with Qnexa is 11 percent, with more than 83 percent of patients losing 5 percent of their weight or more.
Side effects with the drug include depression, migraine and memory lapses.
In May a panel of expert advisers to the FDA voted 18-4 to recommend approval of Arena’s drug, concluding that its benefits “outweigh the potential risks when used long term” in overweight and obese people.