Wednesday, May 23, 2007

Avandia Linked to Heart Attacks

The reason we treat diabetes - the reason we work to keep blood glucose within a normal range - is to reduce the effect of diabetic complications, the most serious being heart disease which is the leading cause of death among people with diabetes.

So it's worrisome that an analysis published in this week's New England Journal of Medicine (NEJM) concluded:
"Rosiglitazone [Avandia] was associated with a significant increase in the risk of myocardial infarction."
GlaxoSmithKline, the maker of Avandia, had a swift response:
"GSK strongly disagrees with the conclusions reached in the NEJM article, which are based on incomplete evidence and a methodology that the author admits has significant limitations."


Avandia was approved by the FDA in 1999 for the treatment of type 2 diabetes. It is a member of a class of drugs known as thiazolidinediones. These drugs act by binding to peroxisome proliferator-activated receptors (PPARs), a group of receptor molecules inside the cell nucleus. Each drug in the class works a little differently, but they all lower blood sugar by increasing insulin sensitivity.

There have been 3 drugs of this class approved for use in diabetes:
  • Avandia (rosiglitazone) approved by the FDA in 1999.
  • Actos (pioglitazone) approved by the FDA in 1999.
  • Rezulin (troglitazone) approved by the FDA in 1997. Rezulin became associated with liver inflammation and was withdrawn from the US market in 2000.
As of today, there has been no recall of the drug. The FDA did issue a safety alert that addresses the findings of this study. They are in the process of conducting their own analysis, both to confirm any risk involved with taking Avandia, and to determine how that risk compares with that of the other drug in this class, Takeda's Actos. There may be regulatory action in the future.

For now, the FDA advises:
"Patients who are taking Avandia, especially those who are known to have underlying heart disease or who are at high risk of heart attack should talk to their doctor about this new information as they evaluate the available treatment options for their type 2 diabetes."

For the NEJM article that spurred the FDA's safety alert (free full access):
Effect of Rosiglitazone on the Risk of Myocardial Infarction and Death from Cardiovascular Causes

For the FDA's safety alert:
FDA Issues Safety Alert on Avandia

For GlaxoSmithKline's press releases:
May 21, 2007 - GlaxoSmithKline strongly defends its record on Avandia
May 21, 2007 - GlaxoSmithKline responds to NEJM article on Avandia

For Avandia's website:
Avandia (rosiglitazone maleate)

News Summaries:
Diabetes Drug Avandia Linked To Heart Risks; Vioxx Parallels Cited
"We Don't Need a Public Panic."