The proposed weight-loss drug Lorcaserin, rebuffed in its bid for Food and Drug Administration approval last October, on Thursday won a recommendation of approval from the agency's advisory committee, a major step toward winning the FDA's go-ahead to enter the U.S. market. If the agency follows the advice of the panel of independent experts--which is common but not routine-- Lorcaserin would become the first new prescription weight-loss drug to go on the U.S. market since Orlistat (now marketed over-the-counter as Alli) was approved in 1999.
The 18-4 vote on Thursday came after the FDA's advisory committee on endocrinological and metabolic drugs weighed evidence on the drug's safety record, presented by Lorcaserin's sponsor, Arena Pharmaceuticals, which developed Lorcaserin in partnership with Eisai Co. Panel members weighed Lorcaserin's effectiveness in promoting weight loss in obese patients against concerns that the drug might damage heart valves, as well as about increased rates of breast and brain tumors in animals given higher than the planned dose. Concerns over those issues were enough to prompt the FDA last October to send Arena Pharmaceuticals back to gather more data.
The advisory panel's FDA staff, which reviews and analyzes new data in advance of the meeting, were generally positive about the data presented by Arena. A report prepared for the advisory panel found that the drug's feared incidental effects on the heart are "unlikely at the proposed clinical dose of Lorcaserin." The report acknowledges the higher rate of benign fibroadenoma seen in rats administered the drug, but concludes the rates of cancersseen in rats are "indicative of negligeable risk in human subjects."