Study Casts Doubts on Vytorin, Zetia
Cholesterol-Lowering Drugs May Not Reduce Plaque Buildup
WebMD News Archive
Congressional Probe of Zetia, Vytorin Research continued...
In a news release issued Monday afternoon, the two congressmen leading the
investigation had harsh words for Merck and Schering-Plough.
"Today's announcement that the ENHANCE study failed to find any positive
benefit from the addition of Zetia to a common, inexpensive, generic therapy
raised concerns that attempts were made to mask the minimal value of this new
drug," Committee on Energy and Commerce chairman John Dingell, D-Mich.,
Rep. Bart Stupak, D-Mich., who chairs the oversight subcommittee, said the
investigation will continue.
"In light of today's results, which were released nearly two years after
the ENHANCE trial ended, it is easy to conclude that Merck and Schering-Plough
intentionally sought to delay the release of this data," Stupak said.
"It's currently unclear whether these companies knew that adding a new
expensive drug accomplished nothing more than an established cheaper generic.
But it is clear that our investigation is far from over."
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.