Contrave Rejection and Obesity Drugs’ Future
Today's a somber day for anyone looking to develop a weight-loss medication. Orexigen's potential obesity drug Contrave has failed to win FDA approval, just as Arena's Lorqess and Vivus's Qnexa before it. In other words, none of the big contenders in the diet drug race we've been covering for nearly a year has panned out.
Contrave came into FDA decision-day with a a glimmer of hope behind it. Last December, an FDA panel voted in favor of approving Contrave, though they recommended that Orexigen conduct a clinical trial after approval to track the drug's cardiovascular risk. In contrast, Lorqess and Qnexa hadn't gotten a thumbs-up from the panel.
But the agency turned out to be more conservative than its advisory panel. In a so-called Complete Response Letter, FDA told Orexigen it needed to conduct that cardiovascular clinical trial BEFORE Contrave could be approved, not after approval. Orexigen's stock fell over 70% on the news this morning. "Such a study would be huge, expensive, and would take years, and the request probably means that Contrave will never hit the market," writes Forbes's Matthew Herper.
So where do we go from here? I hesitate to say that the obesity drug field is dead. We'll certainly continue to see scholarly papers about promising new obesity drug targets. But on the clinical side, the focus is going to have to shift away from weight loss to treating the conditions that tend to go hand-in-hand with obesity, like diabetes. That's what could help tip the safety-efficacy balance in a way that leads to new drug candidates being approved by FDA. This is not a new idea- for instance, C&EN contributing editor Aaron Rowe has covered companies' efforts to mimic bariatric surgery's beneficial effects on diabetes with a pill.
Pfizer is in Rowe's story with a potential diabetes drug in clinical trials. The molecule targets an enzyme that reassembles triglycerides. One of its entries at clinicaltrials.gov says it all: "It is anticipated that PF 04620110 will have anti diabetic effects through inhibition of intestinal triglyceride absorption and potentially weight loss." Pfizer exited obesity drug research in 2008. But it didn't abandon efforts to treat some of the conditions that make obesity unhealthy. If targeting a certain enzyme happens to help with both diabetes symptoms and weight loss, so much the better. But weight loss isn't the top priority.