An advisory group is set to meet Monday to discuss the cardiovascular
safety of GlaxoSmithKline's type 2 diabetes drug Avandia, and the drug may be
in for a rough time.
will pit GSK's own analysis of Avandia (rosiglitazone) clinical trials against
an appraisal of several studies conducted by independent reviewers. The reviewers'
report, released this week as part of a 436-page FDA briefing document, “largely
confirms concerns first raised in May” by Dr Steven Nissen in The New England Journal of Medicine, according
to The New York Times. Nissen's meta-analysis found that patients taking Avandia
face a 43% higher risk of heart attacks than those taking other diabetes drugs
or no medication, while the FDA report pegged the Avandia odds ratio at 38% for ischemic events.
the new report said the risk of heart attack doubles when Avandia is added to
insulin. A similar risk was not found with patients taking Takeda's Actos (pioglitazone).
GSK's chief medical officer is set to make the case for
Avandia's safety. Across multiple sources of data, “there is no consistent or
systematic evidence that rosiglitazone increases the risk of myocardial
infarction or cardiovascular death” compared to other diabetes drugs, the
company said in its own brief issued ahead of the meeting.
A review of both documents “make it seem unlikely Avandia
will remain unscathed,” said Forbes. The
panel could suggest pulling Avandia off the market or recommend the FDA sit on
its hands due to the conflicting studies. Perhaps more likely, the group could
recommend placing additional warnings on the drug or that its use be restricted,
particularly with those also taking insulin. In February the same group of
advisors recommended Avandia's label should get a “black box” warning about ischemic
Doctors have already voted with their prescription pads, sending GSK's market
share in the PPAR class of drugs down to 33% from 51% before Nissen's report, according to IMS Health data cited by The Wall Street Journal. Actos now commands 67% of that market,
compared to 49% in January. Last year Avandia had global sales of $3.38 billion—comprising
7% of GSK's total sales.