Avandia Study Spurs New Heart Risk Debate
Diabetes Drug Doesn't Raise Risk of Death From Heart Disease, Shows Study; Critics Find Flaws
June 5, 2009 -- A company-sponsored clinical trial shows that the diabetes drug Avandia causes no more heart deaths than standard treatment, but critics say the study is flawed.
Avandia, made by GlaxoSmithKline, is an oral drug that makes the body more sensitive to insulin.
But concerns that Avandia causes heart problems has led the American Diabetes Association's treatment guidelines committee to advise against prescribing Avandia in favor of Actos, another drug in the same class with fewer heart-safety concerns -- although both drugs increase a patient's risk of heart failure.
GlaxoSmithKline's RECORD study was supposed to answer these concerns. And according to study leader Philip D. Home, DPhil, of the U.K.'s Newcastle University, it did. Home presented the study findings at this week's meeting of the American Diabetes Association in New Orleans.
"The findings are essentially that in overall cardiovascular terms the drug is safe," Home said at a news conference. "There is no increased or decreased risk of death from heart disease, and that includes the heart failure data."
David Nathan, MD, chairman of the American Diabetes Association guideline committee, said the group would reconsider its recommendations in light of the study findings.
However, the study was unable to determine whether Avandia increases a patient's risk of heart attack. That concern was raised by several experts, including Steven Nissen, MD, chairman of cardiovascular medicine at the Cleveland Clinic.
Nissen remains unconvinced by the final report from Home and colleagues.
"The RECORD trial is seriously flawed," Nissen tells WebMD. "The authors don't reveal the number of patients who were still taking Avandia by the end of the study, but I would estimate this number to approach 50%. Obviously, it is impossible to assess the safety of a drug when patients are not actually taking it."
Home says patients assigned to Avandia treatment took the drug for 88% of the study time. But Nissen says Home's own previously published interim findings do not support this calculation.
Indeed, Home agrees that the study does not answer the question of whether patients taking Avandia have an increased risk of heart attack.