Even if I had another topic planned, how could I not write
this month about Zetia? Another example of panacea to panic, another billion
dollar drug toileted based on preliminary studies. More than 4 million
Americans taking this drug or the combination drug Vytorin (Zetia plus Zocor)
now not sure what to do.
But what should users of Zetia and Vytorin do? It has been
well established that lower LDL or bad cholesterol is good for the heart. The
surprising finding of the ENHANCE trial was that in the groups that received
Zetia, despite significantly lower cholesterol, there was not a corresponding
regression of plaques in the carotid arteries. Since carotid disease is
somewhat predictive of coronary disease, this has raised red flags about the
effective- ness of Zetia at preventing heart attacks and disease.
But as usual, the misreporting of the ENHANCE trial in the
media has obscured several important facts about the drug itself. First and
foremost, there have been NO studies yet about cardiac events. We simply don't
know whether the regular use of Zetia as part of a strategy of
cholesterol-lowering leads to less clinical heart disease or not. Though
cholesterol-based plaque clogging arteries is part of the problem, it is not
the whole story. Second, the study took place over two years, and long-term
effects on the arteries are not known. The conclusions based on this
preliminary information has quickly led to the trashing of a drug in the media
that may still have important uses.
ENHANCE does bring up some of the intrinsic limitations of
combination drugs. I have always been wary of combining two active chemicals in
the same pill because it may be difficult to determine which drug is doing
The real problem here is not with a drug that lowers
cholesterol by blocking its re-absorption in the gut, but with the media's
kneejerk attempts to marginalize this drug into non-existence based on a
preliminary and limited study.
Marc Siegel, MD, is an internist and associate professor of
medicine at New York University and the author of False Alarm: The Truth About
the Epidemic of Fear