- THURSDAY, Aug. 21 (HealthDay News) — U.S. drug regulators said
Thursday that they were investigating whether the cholesterol-lowering
drug Vytorin might be linked to cancer.

The U.S. Food and Drug Administration said it has informed health-care
professionals that the agency was investigating a report from the
so-called Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) trial of a
possible association between the use of Vytorin and an increased risk of a
variety of cancers.

Vytorin is a combination drug made up of the compounds simvastatin and
ezetimibe that's designed to reduce levels of LDL (bad) cholesterol and
cut the risk of cardiovascular problems. It works by decreasing the
production of cholesterol by the liver and inhibiting the absorption of
cholesterol in the intestine.

In a statement released Thursday afternoon, the FDA said it had
obtained preliminary results from the SEAS trial. The trial tested whether
lowering LDL-cholesterol with Vytorin would reduce the risk of
cardiovascular problems in people with narrowing of the aorta, the body's
largest artery. The five-year trial did not show a reduced cardiovascular
risk. But, a “larger percentage of patients treated with Vytorin were
diagnosed with and died from all types of cancer combined, when compared
to treatment with a placebo,” the statement said.

However, the FDA said patients can continue to take the drug. But the
agency urged health-care professionals to monitor their patients for
possible side effects and report them to the agency. While one recent
clinical trial indicated higher rates of cancer for patients taking the
drug, the FDA said two studies currently under way have shown no increased
risk, the Associated Press reported.

The agency said it expects to receive a final study from the SEAS trial
in about three months. It will then take an estimated six months to review
and evaluate the trial data.

Vytorin is made by the drug companies Merck & Co. and
Schering-Plough Pharmaceuticals. It's a combination of Merck's Zocor
(simvastatin), a statin, and Schering-Plough's Zetia. A report earlier
this year found the drug failed to reduce the buildup of plague in
arteries any better than the generic drug Zocor.

Following the FDA's announcement Thursday about the possible
Vytorin-cancer link, several Congressional lawmakers issued a demand for
data on the trial that suggested a potential connection, the AP
said.

Merck and Schering-Plough said they would cooperate with the requests.
The companies defended the drug, saying it is effective at reducing
cholesterol — the use for which it was approved, the AP
reported.

Earlier this week, researchers who last year reported a possible link
between cholesterol-lowering statin drugs and cancer now say that further
analysis has disproved such an association.

“The bottom line is that there is no evidence from this work, the
largest study published to date, that the cholesterol-lowering ability of
statins increases the risk of cancer,” said Dr. Richard H. Karas, director
of preventive cardiology at Tufts Medical Center and leader of a group
reporting the finding in the Journal of the American College of
Cardiology.

A little more than a year ago, a report by Karas and his colleagues in
the same journal described a slight increase in cancer risk among statin
users — about one extra case per 1,000 people. That finding came from 13
trials that gathered information on side effects reported by people who
took the drugs.

The newer report had data from 15 controlled trials involving more than
437,000 person-years of follow-up. The analysis did find a relationship
between low levels of LDL cholesterol — the “bad” kind that clogs
arteries and that statins attack — and a higher incidence of cancer.
However, the team concluded that statins, per se, “lack an effect on
cancer risk across all levels of on-treatment LDL cholesterol.”

An even larger study by Sir Richard Peto, the renowned British
epidemiologist, reported at a meeting but not yet published in a medical
journal, came to the same conclusion, Karas said.

An association between low levels of LDL cholesterol and cancer is no
surprise, said Dr. Daniel Steinberg, professor emeritus of medicine at the
University of California, San Diego. He wrote an editorial accompanying
the report.

“The so-called J-shaped curve has been seen repeatedly when cholesterol
has been measured,” Steinberg said. “In such studies, persons with the
lowest LDL cholesterol on entry show the highest death rate from cancer
than those with higher LDL levels.”

One possible mechanism is that cancer itself reduces LDL cholesterol
levels, he said. “This is especially true of cancers involving the blood
cell system, but it also occurs with cancer of the kidney and elsewhere,”
Steinberg said.

“Whatever the mechanism, the main point should be that studies of much
larger numbers of people in statin trials find no excess of cancers,” he
said.

More information

There's more on statins at the American Heart Association.