Back in 2005, I worried about taking a new drug to market that had a completely new central nervous system mechanism: Acomplia (rimonabant). CNS makes me nervous. I used to work in the area, and I have a healthy respect for how little we know about it. So when you come in with something new, you have to be worried about what's going to happen, and whether your clinical trials are going to be enough to tell you about it.

And sure enough, the long, long delay at the FDA for the drug, which was (in theory) supposed to be approved in the first half of 2006, turned out to hinge on CNS side effects, among them "suicidal ideation". Now a meta-analysis has come out in The Lancet which suggests that patients taking the drug in Europe (one of the few places you can take it) have a much higher risk of depression.

You have to be careful with meta-analyses. But this one's noteworthy because, as the authors point out, depressed mood was an exclusionary factor for the studies concerned. Yet even after winnowing out those patients, the study patients seem to have been 2.5 times as likely to drop out of the trials due to depression as compared to the placebo groups. The studies totaled 2503 patients on the drug, and 1602 in the placebo groups. Depression showed up in 74 and 22 cases in those groups, respectively, which does seem to be a real effect, especially when you start by excluding anyone who seems depressed.

Compare that with the Avandia meta-analysis that has made much so much news (and come close to sinking the drug completely). Out of 14,000 patients, that one had 86 cardiac events in the treatment groups and 72 in the controls, and this in a population with underlying cardiovascular trouble. Depression is not as serious an outcome as a heart attack, to be sure, but it's nothing you'd sign up for, either. Sanofi-Aventis should stop being upset that they haven't gotten the drug on the market here, and start being glad that the lawyers here didn't get a chance to strip a few billion dollars off of them.