TORONTO - Health Canada says Canadians who are taking the diabetes medication Avandia should not discontinue their medication without first talking to their doctor.
The drug, which was approved in March 2000 in Canada, was the subject of a safety alert in the United States on Monday after a new scientific analysis linked it to a greater risk of heart attack and possibly death.
A spokesperson for Health Canada says patients taking the drug should follow up with their physician to discuss all their risk factors for heart attacks, including the increased risk associated with diabetes.
Jirina Vlk says Health Canada is aware of the study on Avandia in the New England Journal of Medicine and is doing its own analysis of the findings.
As in the United States, Health Canada says there are no immediate plans to change the labelling for the medication.
IMS Health Canada says more than one million prescriptions for the drug were filled in Canada last year, and Avandia was ranked third in the oral diabetes class of drugs.
The retail value of the prescriptions was $156 million in 2006, said Sue Callucci, manager of media and public affairs for IMS, which compiles a national prescription drug database.
Health Canada says the risks and benefits for an individual patient have to be weighed against each other, and compared to those of alternative therapies.
The adverse drug reaction database has received approximately 28 Canadian reports of heart attacks in patients using Avandia since 2000 but "the causal nature of the association of these adverse events with Avandia has not been determined," Health Canada said.
More than six million people worldwide have taken the drug since it came on the market eight years ago. Pooled results of dozens of studies revealed a 43 per cent higher risk of heart attack, according to the review published by the New England Journal of Medicine.
The company downplayed the report of heart risks, saying the analysis by Dr. Steven Nissen and statistician Kathy Wolski at the Cleveland Clinic is not definitive scientific proof. In a conference call Monday, Dr. Lawson McCartney who leads Glaxo's diabetes drug development, said the company is not seeing "anything like" the problems reported in the medical journal.
"We remain very confident in the safety and of course in the efficacy of Avandia as an important diabetic medicine," McCartney said.
