Study Casts Doubts on Vytorin, Zetia
Cholesterol-Lowering Drugs May Not Reduce Plaque Buildup
A spokesman for Schering-Plough tells WebMD that the timing of the
trial results release had nothing to do with the congressional
Lee Davies blamed the delay in presenting the findings on the complexity of
interpreting the data, which included some 40,000 visual images that had to be
Davies pointed out that the study was designed to assess plaque buildup in
the arteries in a very high-risk patient population. The trial was not designed
to look at outcomes such as heart
attack, stroke, and death.
The trial included 720 patients with a rare genetic condition predisposing
them to very high cholesterol.
During the two-year study, patients were treated with either high doses of
simvastatin alone or Vytorin, which combines Zetia and simvastatin.
Vytorin was found to lower LDL "bad" cholesterol more than
simvastatin alone, with patients on the combination drug showing a 58%
reduction in LDL vs. a 41% drop for those on the single drug.
The side effect profile for the two treatments was similar, and was
consistent with the labeling for Vytorin, Davies says.
But Vytorin users had slightly more plaque buildup in their carotid
arteries, although the difference was not statistically significant and could
have been due to chance.
Davies says three larger ongoing trials, involving some 20,000 patients,
should answer questions about whether Zetia and Vytorin prevent more adverse
events and deaths than statins alone.
He questions the reaction to the ENHANCE results, which he called a
"small, academic trial."
"The implications drawn from the findings in terms of clinical use seem
out of proportion to what the trial was designed to demonstrate," he says.
"One should keep in mind that while statins are the first-line therapy for
most people, they are not enough for many people and are not appropriate for
some. There is a need for viable alternatives, and Zetia and Vytorin have
proven to be very effective for lowering LDL levels."
Combined quarterly sales of Zetia and Vytorin reached $1.3 billion in the
second quarter of 2007, with Vytorin sales growing by 30% and Zetia sales
increasing by 21%, according to the Dow Jones news service MarketWatch.
Docs Weigh in
A statement released Tuesday afternoon by the American College of Cardiology
(ACC) urged patients taking Zetia or Vytorin to remain calm in the wake of the
The statement made it clear that ACC still considers Zetia a reasonable
option for patients who cannot tolerate statin drugs or can only tolerate
"There is no reason for patients to panic," the statement read. "Concerned
patients using these drugs should talk to their health care professional. This
is not an urgent situation and patients should never stop taking any prescribed
medications without first discussing the issue with their health care