Manufacturer restricts use of diabetes drug Avandia
Last Updated: Wednesday, November 7, 2007 | 4:37 PM ET
The Canadian Press
The manufacturer of a drug for treating Type 2 diabetes has placed new restrictions on use of the medication based on a Health Canada review of clinical data pointing to an increased risk of heart-related problems in some patients.
GlaxoSmithKline Inc., in consultation with Health Canada, is updating prescribing information on products made from or containing the drug rosiglitazone: Avandia, Avandamet and AvandarylTM.
Once touted as the gold standard for preventing Type 2 diabetes in high-risk patients, rosiglitazone lost its glitter after a study published in the New England Journal of Medicine in May showed Avandia significantly raised the risk of heart attack and possible death.
The NEJM analysis of 42 studies revealed a 43 per cent higher risk of heart attack for those taking rosiglitazone compared to people taking other diabetes drugs or no diabetes medication at all.
In new prescribing information, GlaxoSmithKline said patients may take Avandia in combination with metformin when good blood-sugar control does not result with metformin alone. Metformin is an anti-diabetic drug sold under the brand names Glucophage, Glumetza or in generic forms with "metformin" as part of the name.
As well, "Avandia may be used alone or with a sulfonylurea drug [such as glyburide], only if metformin use is contraindicated or cannot be tolerated," the company said in a release.
"The new labelling also emphasizes that Avandia should not be used in patients with any stage of heart failure."
Glaxo said patients taking rosiglitazone and especially those with underlying heart disease or with a high risk of heart attack or heart failure should talk to their doctor about the benefits and risks of continuing the drug.
Other important restrictions for patients:
- Rosiglitazone should not be taken if insulin is also being used.
- Rosiglitazone should not be used as part of a "triple therapy" in combination with metformin and a sulfonylurea drug.
Rosiglitazone can cause the body to retain fluid, which can worsen some heart problems and lead to heart failure, swelling and weight gain.
Several lawsuits have been launched in Canada and the United States over the medication's adverse effects, and drug safety regulators in both countries have been investigating its safety.
