Lorcaserin: a novel serotonin 2C agonist for the treatment of obesity

Obesity has become an epidemic in the United States and its prevalence continues to increase. Adjunctive treatment with pharmacotherapy is often reserved for individuals who fail to achieve their intended weight goals with diet and exercise alone. Current approved therapies for weight loss include phentermine, diethylpropion, orlistat, and phentermine/topiramate. The objective of this paper was to review the place of lorcaserin, a novel serotonin 2C agonist, which was FDA approved in July 2012. Unlike contemporary lipase inhibitors and sympathomimetic amines, lorcaserin is purported to reduce food consumption and increase satiety.

A systematic review of the literature for all relevant articles was performed through January 2013 using MEDLINE, Web of Science, and International Pharmaceutical Abstracts using key words related to lorcaserin.

Three phase III clinical studies have been published evaluating the efficacy and safety of lorcaserin in various obese populations. A higher proportion of patients receiving lorcaserin (∼47%) lost more than 5% body weight from baseline in comparison with the placebo group (∼25%; p < 0.05 in all studies). Those receiving the recommended dose of lorcaserin 10 mg twice daily lost on average ∼6 kg of body weight from baseline versus ∼3 kg with placebo. Patients with diabetes mellitus also saw significant reductions in their HbA1c with lorcaserin (∼0.9%) versus placebo (∼0.4%; p < 0.001). Lorcaserin is generally well tolerated with the most commonly experienced adverse events being nausea, dizziness, headache, upper respiratory tract infections, and nasopharyngitis. Cardiovascular evaluations showed no appreciable increase in valvulopathy with lorcaserin use versus placebo.

For now, pharmacists should continue to recommend the use of lorcaserin as a complement to, not in lieu of, ongoing lifestyle and behavioral modification.