If FDA follows the advice of its advisory committee and approves Arena Pharmaceuticals Inc.'s lorcaserin, the biotech may be able to carve out a niche for the obesity compound despite modest efficacy and potential hurdles to use, including advice that recurring echocardiograms be used to rule out a cardiovascular risk.

Last week, FDA's Endocrinologic and Metabolic Drugs Advisory Committee voted 18-4 with one abstention that the benefit-risk profile for lorcaserin supports approval for obesity.