New Delhi: November 16, 2007 - The United States's Food and Drug Administration has directed pharmaceutical major GSK to put a "black box" warning on its diabetes drug Avandia, stating that its use could cause chest pain or heart attack. Over two million people worldwide take the drug for Type-II diabetes.

Generic versions of Avandia — its scientific name is rosiglitazone maleate — are available under 10 brand names in India and sold to about eight million people. In India, GSK sells it under Windia brand name.

A "black box" warning is the FDA's strongest warning, falling just short of withdrawing the drug from the market. The warning is made mandatory when studies indicate the drug carries a significant risk of serious or life-threatening side effects.

Concerns about Avandia's safety started when a study in The New England Journal of Medicine in May reported that patients who used it had a 43 per cent higher risk of heart attack and a 64 per cent higher risk of dying of heart problems.

"We are keeping Avandia in the market because we have concluded that there isn't enough evidence to conclude the risk for heart attack or cardiac ischemia is higher than for other Type-II diabetes drugs," said the FDA's Dr Janet Woodcock.

GSK will start a trial comparing Avandia with other drugs to see whether the cardiovascular risks are unique to it alone.

In India, no such warning on rosiglitazone has been issued by the Drugs Controller General Dr M. Venkateswarlu.

Rosiglitazone is popular here because besides regulating insulin and blood sugar, it is found to have a favourable impact on lipids (blood fats like cholesterol), coagulation (clotting) and fat in liver. It is a third-line drug prescribed after two lines of treatment — like sulfisoxazole and metformin — become ineffective. Many firms here were promoting it as a drug that prevents diabetes.

The lesson in this, says Dr Anoop Misra, head, department of metabolic diseases, Fortis Group of Hospitals, is that both physicians and patients should refrain from blindly accepting new medicines as cure-alls when existing therapies have been established to be equally effective.

"The mechanism for increased risk of death from heart attacks may be due to the adverse effect of rosiglitazone on lipids, particularly because of the increase in bad cholesterol by 18.6 per cent. The drug was claimed to ‘have a favourable effect on lipids' when launched, which is a false claim," said Dr C.M. Gulati, drug specialist and editor of the Monthly Index of Medical Specialities.