Diabetes Drugs and Heart Risk
New Studies Link Avandia, but Not Actos, to Heart Attacks
Sept. 11, 2007 - New studies link the oral diabetes drug Avandia -- but not the related drug Actos -- to heart attacks.
One of the studies published in The Journal of the American Medical Association is a new analysis of data from Avandia clinical trials by Wake Forest University researcher Sonal Singh, MD, and colleagues.
Using stringent criteria for data selection -- one of the study authors helped write the international guidelines for analyzing side effect data from multiple studies -- the study showed that Avandia increases a diabetes patient's risk of heart attack by 42%.
"Regulatory agencies ought to re-evaluate whether [Avandia] should be allowed to remain on the market," Singh and colleagues conclude. "Health plans and physicians should not wait for regulatory actions. They should avoid using [Avandia] in patients with diabetes who are at risk of cardiovascular events, especially since safer drugs are available."
The 42% increase in heart attack risk seen in the Singh study is nearly the same as the 43% risk found in a controversial earlier analysis led by Cleveland Clinic cardiology chairman Steven Nissen, MD. Unlike the Nissen analysis, however, the new study does not link Avandia to a higher risk of heart death.
"It is absence of evidence, not evidence of absence of an effect on mortality," Singh tells WebMD. "But at least based on this information, we cannot say Avandia increases mortality."
GSK Disputes Avandia Findings
Avandia maker GlaxoSmithKline says the Singh team's conclusions "offer no new information on the safety of Avandia." In a statement, GSK notes that the stringent criteria used in the study results in the use of data from only four studies and "reflects a difference of only 11 events in 14,291 patients" between the Avandia group and a control group.
"On this limited meta-analysis, in the context of all the other evidence, we believe it is inappropriate for the author to advise doctors to disregard the FDA’s advice -- which is to keep patients who are effectively controlling their diabetes on Avandia," the GSK statement says.
Singh says the FDA did not conduct a full risk-benefit analysis of Avandia and that its Avandia advisory panel did not evaluate the drug's full risk profile.