The U.S Food and Drug Administration adviser on Wednesday said that
Drugs designed to control type 2 diabetes should be subjected to more
through safety reviews to ensure they don’t raise the risk of heart
problems.The panel of outside experts voted 14-to-2, at the end of a
two-day meeting, to recommend that all makers of these drugs conduct
long-term cardiovascular trials, even if the drugs show no signs of
heart problems in initial trials.
Majority of the panel members also recommended that trials assessing
cardiovascular risk should be carry out before a drug is approved for
the market; these could be a part of a phase III trial to rule out any
significant heart risk. Long-term trials could follow once the drugs
was on the market, the adviser said.
Currently, the FDA only requires that drugs for type 2 diabetes
lower blood sugar, which is thought to protect diabetics from the
debilitating side effects of the disease.
Although the FDA is not required to follow its advisory panels’ recommendations, it usually does.
The panel’s vote comes less than a year after the FDA was harshly
criticized for its handling of the type 2 diabetes drug Avandia
(rosiglitazone), made by GlaxoSmithKline. The drug was approved in
1999, but the FDA added a “black box” warning about an increased risk
of heart attack last November. And the agency decided to keep Avandia
on the market because it concluded that the risk of heart attack wasn’t
any higher than that associated with similar medications.
Dr. Steven Nissen, chairman of the Cleveland Clinic’s department of
cardiovascular medicine, first raised concerns about Avandia and heart
attack risk in a study published last year. He said in November that he
welcomed “the addition of a black box warning for the risk of heart
attack from Avandia,” but would have preferred a warning “written with
greater clarity,” like the one used by Health Canada, the FDA’s
counterpart in Canada.
The Canadian label says Avandia is not to be used as the sole
medication for type 2 diabetes except for patients who can’t take
metformin, another drug that also lowers blood sugar. The label also
states that Avandia is not to be used by any patient with heart failure.
The controversy over Avandia started in May 2007, when a study by
Nissen and colleague Kathy Wolski, published in the New England Journal
of Medicine, found a 43 percent increased risk of heart attack among
patients taking the drug. Nissen said he uncovered the risk after
poring over data from 42 studies of Avandia.
On Tuesday, Nissen told the FDA advisers that the agency should make
companies demonstrate that their type 2 drugs do not increase risks of
cardiovascular disease before being approved, the Wall Street Journal
reported.
“Merely lowering blood-glucose levels in diabetes is too
simplistic,” Nissen told the panel. “We must reduce the complications
of diabetes, including cardiovascular disease.”
Should the agency adopt the panel’s recommendation, the additional
clinical trials could add years and millions of dollars to the
development of any new type 2 diabetes drug. Companies such as
Bristol-Myers Squibb and AstraZeneca are currently working on such
drugs, the Journal reported.
About 20.4 million Americans have type 2 diabetes, which the
complications can lead to blindness, kidney failure and heart disease.
About 75% of diabetics die from cardiovascular disease.
Sen. Charles Grassley, R-Iowa, is investigating the FDA’s approval
of Avandia and the cholesterol-lowering drug Vytorin, which did not
reduce the build-up of plaque in the arteries.
Recently, the FDA denied approval of another cholesterol-lowering
drug from Merck & Co. The denial sparked speculation that the
agency has tightened its approval standards for these medications.
However, the FDA hasn’t said whether changes in its approval process
are being considered, the Associated Press reported.
SOURCES: July 2, 2008, teleconference, U.S. Food and Drug Administration; The Wall Street Journal; Associated Press
|
