Merck and Schering-Plough saw two more strikes leveled at their cholesterol combo med Vytorin yesterday. First, preliminary results from a new trial showed that Vytorin didn't benefit patients with heart-valve disease any more than placebo did. And second, researchers found a statistically significant increase in cancer cases--and deaths from cancer--among the Vytorin patients. Softening the blows somewhat was the fact that Vytorin cut complications from coronary disease, but that benefit might come solely from the simvastatin portion of the drug; researchers just don't know.
The companies downplayed the cancer-risk news, bringing in a top cancer epidemiologist, who looked at the data from this study and two other ongoing Vytorin trials and concluded that a causal link was "highly unlikely." His reasoning: The numbers are small enough to have arisen by chance; a variety of cancers showed up, rather than just one; and no increase in cancer cases was found in the other two studies. Other experts were more skeptical, pointing out that the other two studies haven't spanned as much time as the four-year one discussed yesterday, and that while the number of cancer cases in those studies wasn't higher among the Vytorin patients, the number of cancer deaths was: 136 in the Vytorin group versus 95 among those taking other drugs or placebo, according to the New York Times.
The bottom line: There's no proof that Vytorin causes cancer. But the news is likely to hurt the drug anyway, by making already skittish doctors and patients even more so. Merck, for one, is worried; the company pulled its earnings guidance for revision, saying it's not yet sure how much impact the new study might have on 2008 results. We'll see what they decide.