Development of taranabant for obesity discontinued

Merck has announced that they are discontinuing development of taranabant, an investigational selective blocker of the cannabinoid-1 (CB-1) receptor that was being studied for the treatment of obesity.

Merck has announced that they are discontinuing development of taranabant, an investigational selective blocker of the cannabinoid-1 (CB-1) receptor that was being studied for the treatment of obesity. According to the results of a phase 3 study presented at the 57th Annual Scientific Session of the American College of Cardiology in March 2008, patients treated with taranabant in combination with diet and exercise experienced statistically significant weight loss compared with patients treated with placebo. Phase 3 data demonstrated, however, that more adverse events were observed in patients treated with higher doses of the agent, an outcome that led to Merck’s decision to halt development.

Rimonabant, another CB-1 receptor antagonist, was withdrawn from regulatory consideration by Sanofi-Aventis in 2007. An FDA advisory committee had recommended against approval of the agent because of an increased risk of psychiatric and neurologic adverse effects in patients treated with rimonabant.