The Food and Drug Administration announced today that it has approvedlorcaserin (to be marketed as Belviq)for the treatment of adult obesity. The drug was developed by Arena Parmaceuticals and went through two advisory committee panels. The final panel voted to recommend approval by a vote of 18-4. This is the first drug for treating obesity approved by obesity since sibutramine was approved in 1997.
Lorcaserin is a novel drug that targets a specific serotonin receptor. It was a different serotonin receptor which was implicated in heart valve problems associated with use of the dexfenfluramine component of Fen-Phen. The FDA briefing document for the Advisory Committee meeting on May 10, 2012 states that it “is unlikely at the proposed clinical dose” will activate the receptor implicated in the heart valve problem.
The receptor lorcaserin does impact is concentrated in the central nervous system (CNS) and regulates feeding behavior.
In the latest published study of the drug, the BLOOM-DM study led by Patrick O’Neil, 604 patients who were obese or overweight with type 2 diabetes were randomized into a treatment group and a placebo group. Both groups received lifestyle counseling. The group on drug lost 4.5-5% of their initial body weight while the placebo group lost 1.5%. PubMed: Clinical Trial of Lorcaserin in Type 2 diabetes Weight loss in patients with type 2 diabetes is notoriously difficult to achieve. A 5% weight loss is considered to provide clinically meaningful changes. Weight reduction was evident at 2 weeks which means that patients who don’t see weight loss are likely to discontinue use early on in treatment. Glycemic control improved more in the lorcaserin group. There were not significant changes between the group on drug and on placebo in regard to cholesterol, triglycerides and blood pressure. The lack of statistical significance may be due to the use by a majority of patients being on blood pressure or lipid medications at the start of the trial.
Arena Pharmaceuticals, developer of lorcaserin, has agreed to conduct a number of post-approval trials, including one to assess cardiovascular effects.