Rimonabant - A novel CB1 receptor antagonist for the treatment of obesity

Obesity is on the rise in the United States, with 60.5% of the adult population overweight and 23.9% obese as of 2005. Up to 10% of an industrialized country's healthcare budget often can be spent on obesity and associated comorbidities. Rimonabant (SanofiAventis), a novel CB1 receptor antagonist, is approved in Europe for the treatment or obese or overweight patients with associated risk factors. In February 2006, FDA issued an approvable letter for rimonabant for weight management and a nonapprovable letter for smoking cessation. At press time, the manufacturer was continuing to work with FDA in resolving the issues required for approval of both NDAs. Clinical trials, in addition to demonstrating efficacy in obesity, also have demonstrated a potential role of rimonabant in cardiovascular disease and type 2 diabetes. Rimonabant 20 mg is to be taken once daily before breakfast. Adverse events are relatively benign, with psychiatric adverse events being the leading cause for discontinuation of treatment. The benefit of continuing rimonabant therapy for a duration of 2 years is evident, but therapy could potentially be continued for a longer duration based on results from future studies.