Side-effect reports soar after diabetes-drug risks cited
After an analysis tied Avandia to possible heart risks, reports to regulators of problems tripled.
In the month after a surprising analysis revealed possible heart risks from the blockbuster diabetes drug Avandia, reports of side effects to federal regulators tripled.
The spike is a sign that doctors probably were unaware of the drug's possible role in their patients' heart problems and so may not have reported many such cases in the past, several experts said.
It also shows the flaws of the safety tracking system and suggests that a better one might have detected a potential problem before the drug had been on the market for eight years.
Rosiglitazone, sold by GlaxoSmithKline PLC as Avandia and Avandamet, is used to control blood sugar and helps more than 6 million people worldwide manage Type 2 diabetes. These people already are at higher risk for heart attacks, so news that the drug might raise it further was disturbing.
In the 35 days after May 21 - the date the New England Journal of Medicine published the analysis online - reports of heart attacks, deaths and hospitalizations leaped. The rise appears in data obtained by the Associated Press through a Freedom of Information Act request to the U.S. Food and Drug Administration.
Five heart attacks were reported in the 35 days before the study, compared with 90 in a similar period afterward. Heart-related hospitalizations went from 11 to 126.
Reporting a drug's side effects is voluntary - a crude indication, rather than a scientific measure, of patients' problems.
The FDA relies on this unenforced system once a drug is on the market, but critics say it leads to haphazard oversight in which problems can be missed because doctors do not connect the dots between a drug and symptoms they see in an individual patient.
The published analysis of Avandia likely led to more cases being reported, said Alvin C. Powers, a diabetes specialist at Vanderbilt U.
"Now, patients and their doctors are much more aware of the possible link between Avandia and cardiovascular disease. This is good - this is going to help us going forward to determine whether or not this drug is safe."
British-based Glaxo insists the drug is safe and effective.
"This is a very well-known phenomenon," where news reports lead to increased reporting, said Mary Anne Rhyne, a company spokeswoman. "It's good that there's awareness of the reporting system, but drawing conclusions on such data is inappropriate."
The FDA plans hearings on safety concerns about the drug on July 30. Meanwhile, diabetes experts have advised users of the drug to talk to their doctors and not to immediately discontinue it.
The side effects that were reported - not proven - range from minor blisters to sudden cardiac death. The FDA listed rosiglitazone as the "primary suspect" in most cases.
The issue has roiled the medical community and sparked congressional probes into whether the FDA is properly investigating safety issues.
The agency issued a "safety alert" about the drug only after the May 21 study came out, even though Glaxo had informed the FDA of its own analysis of heart risks nearly a year beforehand and possibly as early as 2005.
Avandia's label warns about possible heart failure and other heart problems when taken with insulin. The drug also raises LDL, or bad cholesterol, and can cause fluid retention and weight gain.
