FDA Reviews Cardiovascular Risk Data for Rosiglitazone

The FDA is investigating potential safety issues related to rosiglitazone maleate, which is used to treat type 2 diabetes, but has suggested no specific changes related to the drug at this time. FDA officials currently are reviewing data from numerous clinical trials involving rosiglitazone, which is the sole active ingredient in the brand-name prescription drug Avandia and an ingredient in two other antidiabetic drugs, Avandamet and Avandaryl.

According to an FDA information sheet for health care professionals, evidence about the risk of ischemic cardiovascular events in patients treated with rosiglitazone is contradictory.

"(The) FDA is carefully weighing several complex sources of data, some of which show conflicting results, related to the risk of heart attack and heart-related deaths in patients treated with Avandia," said Steven Galson, M.D., M.P.H., director of the FDA's Center for Drug Evaluation and Research, in an FDA news release.

Concerns came to light when the sponsor of the drugs, GlaxoSmithKline, provided the FDA with a pooled analysis of 42 randomized, controlled clinical trials that compared rosiglitazone with other antidiabetic therapies in patients with type 2 disease. Although the studies examined a wide range of primary efficacy endpoints and varied in their duration, patient selection criteria and other methodology, the analysis suggested that patients receiving short-term (most studies lasted six months) rosiglitazone therapy may have a more than 30 percent increased risk of heart attack or heart-related problems.

The FDA continues to review the data from that analysis, as well as from other trials involving rosiglitazone, including a large, multicenter randomized trial that is still ongoing. At this time, however, the risks of ischemic cardiovascular events associated with rosiglitazone use remain unclear.

"We will complete our analyses and make the results available as soon as possible," Galson said in the news release. "FDA will take the issue of cardiovascular risk associated with Avandia and other drugs in this class to an advisory committee as soon as one can be convened."

The FDA is advising patients currently taking rosiglitazone to consult their physicians about alternate treatment options, but they caution that there are inherent risks associated with switching diabetes treatments, even in the absence of specific risks. The FDA recommends health care professionals "factor this new information into their individual treatment decisions for patients."

Meanwhile, GlaxoSmithKline has posted various resources about Avandia and related issues on its Web site; those materials include an Avandia press kit, complete with background materials. Health professionals and patients also can visit the company's Avandia Web site for more information, including some Spanish-language documents.

Prescribing information for Avandia, including cardiovascular risk information, may be downloaded from the FDA Web site. (PDF file: 29 pages / 168 KB. More about PDFs.)