Glaxco Money Helped Skew the Debate about Avandia Dangers

by Tony Isaacs

In a story that was mysteriously pulled within hours of being posted, The Independent reported last Friday that a new study posted in the British Medical Journal has indicated that the pharmaceutical giant GlaxcoSmithKline (GSK) used money and influence to skew the debate about the controversial diabetes drug Avandia.  Avandia, Glaxco's tradename for the drug rosiglitazone which is prescribed for type II Diabetes, has been at the center of a controversy since news about its increased risk for heart attacks and strokes was reported in 2007.

The new study found that over 90% of the scientists who backed the drug Avandia had financial links to the pharmaceutical industry.  The disclosure will likely renew concern about the influence of the multinational pharmaceutical companies on patient safety, where a warning about a drug can wipe out billions of dollars in profits.

Researchers from the Mayo Clinic in Minnesota – one of the few US research organizations that does not rely on commercial sponsorship – analyzed more than 200 articles published in scientific journals, including original papers, editorials and letters, which commented on the heart attack risk associated with Avandia after 2007.

By searching other publications by the same authors, the researchers found almost half of the authors of studies and articles about Avandia had financial conflicts of interest but almost half of those who did failed to disclose it. Of the authors who had positive views about Avandia, 94 per cent had financial links with pharmaceutical companies involved in diabetes and 87 per cent had financial links with the drug's manufacturer, GSK.

In contrast, less than 30 per cent of those with financial links with the industry "expressed unfavorable views" of Avandia. Those authors who were critical of Avandia safety were "largely free of identifiable conflicts of interest", the study said.  Notably, of 29 articles found which strongly recommending the rival Eli Lilly drug, Actos, as a replacement for Avandia, 25 were by authors with financial links to Lilly.

Said the researchers: "How could interpretation of the same evidence result in disparate and impassioned positions? We aimed to determine whether financial conflicts of interest with pharmaceutical manufacturers could be fuelling this fire. From our findings, it appears that the answer is yes."

Mohammad Murad, assistant professor of medicine, who led the study, said that "Avandia should probably be withdrawn. There are a lot of other options available now.”

Last month, the US Senate’s Finance Committee reported that Glaxco knew that "there were possible cardiac risks associated with Avandia" (rosiglitazone) for several years before a 2007 study in the New England Journal of Medicine showed a link between the drug and heart attacks.  In a 342 page report released on February 20th, the committee said the company should have warned patients and the Food and Drug Administration. "Instead," the report stated, "GSK executives attempted to intimidate independent physicians, focused on strategies to minimize or misrepresent findings that Avandia may increase cardiovascular risk, and sought ways to downplay findings that a competing drug might reduce cardiovascular risk."

The senate report also asked the U.S. Food and Drug Administration why it allowed a clinical trial of Avandia to continue even after it was estimated that the drug caused 83,000 heart attacks between 1999 and 2007.  Though the FDA did order a warning to be included on Avandia's label in 2007, the warning only stated that the drug "might increase the risk of heart attacks, though the data on those risks was inconclusive".  Later it was disclosed that the FDA's internal safety experts came within one vote of recommending a withdrawal of Avandia.

FDA documents leaked to The New York Times last month revealed that about 500 heart attacks and 300 cases of heart failure could be averted every month because Avandia can hurt the heart.  As reported in the Times, rosiglitazone was linked to 304 deaths during the third quarter of 2009.

Avandia was one of the biggest selling drugs in the world prior to 2007, when the New England Journal of Medicine reported that patients who took Avandia had a 43 percent greater risk of heart attack.  Since then, sales have declined precipitously while the number of articles favorable to Avandia have risen.

Sources included:

http://www.independent.co.uk/life-style/health-and-families/health-news/glaxo...
http://www.nytimes.com/2010/02/20/health/policy/20avandia.html
http://www.bmj.com/cgi/content/extract/340/feb23_3/c1107