Orexigen's (NASDAQ:OREX) Contrave could join VIVUS' (NASDAQ:VVUS) Qsymia and Eisai and Arena Pharmaceuticals' (NASDAQ:ARNA) Belviq on the obesity market in the middle of next year after a trial measuring its safety read out today. The biotech plans to resubmit its marketing application to the Food and Drug Administration in the next few weeks.

The agency rejected Contrave in 2011 asking for a large trial to rule out cardiovascular risk. Orexigen worked out a deal with the agency -- called a Special Protocol Assessment -- that Contave could be approved if the trial showed that it was highly likely that the drug didn't double the cardiovascular risk.

The exact risk wasn't released because the trial is ongoing. Orexigen needs to keep the number a secret because it could influence the patients in the trial that are still taking Contrave or a placebo.

Most safety data
Orexigen and its marketing partner Takeda have the most cardiovascular safety data of the three new obesity drugs. Neither VIVUS nor Eisai and Arena Pharmaceuticals can say that their drugs don't double the cardiovascular risk.

It isn't really clear how much that will be worth at this point though. Saying the drug isn't really, really unsafe isn't saying very much at all. The FDA doesn't have any reason to believe Qsymia and Belviq cause a huge increase in cardiovascular risk; the agency didn't even make VIVUS and Arena Pharmaceuticals run safety trials.

It's not like the data show Contrave is producing a cardiovascular improvement. Orexigen and Takeda can't even say Contrave has the same cardiovascular risk with any degree of certainty.

Yet. Remember, the trial is still ongoing.

The problem here is that statistics is driven by the number of events. This interim look was conducted after 87 events -- heart attack, stroke, and cardiovascular death -- occurred in both treatment groups combined and was really only designed to rule out an excessive risk.

The subsequent looks after more events occur could increase the confidence that the drug has similar cardiovascular risk to placebo or might even show that the drug is improving cardiovascular outcomes. Losing weight should help patients improve their cardiovascular risk, so the latter isn't out of the question, although it might be hard to show a statistically significant improvement.

Making lemons into lemonade
At the time, the FDA's requirement to run a cardiovascular outcomes trial looked like a major setback for Orexigen, delaying the approval of Contrave by more than three years.

As it turns out, VIVUS and Eisai have had to work really hard to get doctors to warm up to obesity drugs. After Orexigen is approved, Takeda can piggyback on that effort and will have cardiovascular data that should make doctors even more comfortable. Eventually.

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