Flush That Outcomes Study

Merck's original idea seemed low risk. Niacin works pretty well at raising good cholesterol but has this annoying side effect of causing patients to feel hot and sweaty (flush). If you can add something to avoid the flushing side effect, you could take sales away from Abbott Labs' niacin drug called Niaspan and probably even increase the market.

And thus, Cordaptive was born.

But in 2008, the Food and Drug Administration flushed the idea of a quick approval based on laboratory tests showing that Cordaptive increased good HDL cholesterol, reduced bad LDL cholesterol, and reduced lipid levels. Merck had to wait for an outcomes study to show that the drug decreased heart attacks, strokes, and other cardiovascular events.

That's not low risk. Nor is it cheap. But Merck pressed on.

Unfortunately, more than four years later, the outcomes study has failed. More than 25,000 patients were enrolled in the study, with half of the patients being followed for at least 3.9 years. Patients who took Cordaptive and a statin -- Pfizer's Lipitor, Merck's Zocor, or AstraZeneca's Crestor, for example -- didn't have a significantly lower occurrence of heart complications (coronary deaths, non-fatal heart attacks, strokes, or revascularizations) compared to patients who just took a statin.

Patients taking Cordaptive had more side effects as well -- which isn't a big deal for the U.S. since the trial failed its efficacy endpoint -- but Cordaptive, which also goes by the trade name Tredaptive, is approved in 70 different countries including those in the EU. Not only does it seem impossible for Merck to get Cordaptive approved in the U.S., but Merck has to worry about it getting pulled off the market elsewhere.

The failure should give investors in Amarin pause. The biotech is running an outcomes study testing its fish oil Vascepa in patients with medium-high lipid levels. The drug has already been shown to lower lipid levels in that patient group, but this trial will test whether that translates into fewer cardiovascular events. My guess is that it does, but that it might not be easy to prove. Like in Merck's trial, all of the patients in Amarin's trial will be taking a statin, which does a pretty good job at lowering cardiovascular risk. So do lifestyle changes. Proving that a drug decreases the risk further can be difficult.

The FDA has agreed to review Vascepa for patients with medium-high lipid levels when the outcomes trial is substantially enrolled based on the previous trial measuring lipid levels with a laboratory test. It would certainly be wrong for the agency to renege on that deal, but given the number of cardiovascular outcomes trials that have failed recently, investors should factor in that it's at least a possibility. The risk of the outcomes trial failing could also be the reason Amarin has failed to find a buyer or partner.

The article Flush That Outcomes Study originally appeared on Fool.com.

Fool contributor Brian Orelli has no positions in the stocks mentioned above. The Motley Fool has no positions in the stocks mentioned above. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.

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