Vytorin heart study expanded, results being delayed

CHICAGO (Reuters) -
U.S. researchers said on Friday they
plan to expand the size of a major study to determine the heart
benefits of the controversial cholesterol fighter Vytorin,
which they said would delay results until 2012.

Vytorin combines the statin Zocor, known generically as
simvastatin with another cholesterol medicine, Zetia or
ezetimibe, and is marketed by a joint venture of Merck %26 Co and
Schering-Plough Corp.

The study tests Vytorin against Zocor alone, which is now
available in cheaper, generic form. The companies hope to show
added benefits from the combination drug.

Academic researchers running the trial said in a statement
they would expand the study to 18,000 patients to strengthen
the results, which aim to show that the drug prevents heart
attacks and other heart problems. The study, originally
designed for 10,000 patients, is expected to be completed in
2011.

Trial chairman Dr. Eugene Braunwald of Brigham and Women%26#39;s
Hospital said in a statement that expanding the trial will
allow researchers to test definitively whether the additional
lowering of low-density lipoprotein -- or LDL, the so-called
bad cholesterol -- with Zetia will translate into additional
benefits for patients.

Researchers have been awaiting the results of the study,
dubbed "IMPROVE-IT," to resolve questions raised by an earlier
study released in January that suggested the higher-priced
combination drug Vytorin fared no better than an inexpensive
statin in patients with an inherited form of heart disease.

In January, Merck and Schering-Plough announced that
Vytorin did not stop the accumulation of fatty deposits in
arteries any better than Zocor in these high-risk patients.

While Vytorin significantly reduced cholesterol levels, it
did not slow the disease any better than Zocor alone.

That trial, known as ENHANCE, has garnered intense investor
interest because Vytorin and Zetia have annual sales of about
%26#36;5 billion, and are important to future earnings growth of the
companies.

And because it took the companies nearly two years to
release the ENHANCE results, Michigan Democratic Reps. John
Dingell, chairman of the Committee on Energy and Commerce, and
Bart Stupak, chairman of the Subcommittee on Oversight and
Investigations, said they suspect the drugmakers suppressed the
data to protect their profits.

They said they are investigating the way Merck and
Schering-Plough handled the study and have asked the U.S. Food
and Drug Administration for records related to television
commercials promoting the drug.

Many experts have said the question of whether adding the
drug Zetia to further lower LDL cholesterol actually helps
patients avoid heart problems will not be fully settled until
the IMPROVE-IT results are released.

"It%26#39;s that much longer before you get any answers," said
Dr. Harlan Krumholz of Yale University, responding to news of
the delay.

Krumholz will serve on a panel of experts that is set to
discuss the full ENHANCE study results on Sunday at a meeting
of the American College of Cardiology in Chicago.

(Additional reporting by Bill Berkrot; Editing by Gary
Hill, Richard Chang)