Diabetes drug Avandia could be a killer

Further concerns about the drug were raised in a BBC Panorama programme on Monday.

The MHRA - the regulatory agency for Britain's medicines and health-care products - said in July that the diabetic drug rosiglitazone, manufactured by pharmaceutical giant GlaxoSmithKline (GSK) and marketed as Avandia, should be withdrawn.

But it is still being prescribed through the NHS even though the British Medical Journal (BMJ) believes the drug should never have been licensed.

Rosiglitazone was approved by the European Medicines Agency in 2000 to help lower blood sugar levels in patients with type two diabetes.

GSK said the drug, once its second biggest seller, was "safe and effective when it is prescribed appropriately."

But several studies have found that its use may lead to a small overall increase in the risk of heart attacks.

Dr Yoon Loke, a clinical pharmacologist at the University of East Anglia, has warned the drug could have caused an extra 1,000 heart attacks and around 600 extra cases of heart failure in Britain last year.

BMJ investigations editor Dr Deborah Cohen said the European agency's approval process was not rigorous enough.

She raised concerns about the quality of GSK's data, the lack of trial results for independent scrutiny and failures by the profit-driven company to act on safety fears.

Doctors are already advising that no new patients should start taking the drug and patients already using it should review their options and stop taking it if at higher risk of heart disease.

"Ten years after the release of rosiglitazone, we still cannot accurately quantify the harm to which we were exposing our patients," Professor John Yudkin of University College London warned.

"We need to be absolutely certain that our long term treatments for type two diabetes are not causing the very harm they are meant to prevent.

"And if the regulatory bodies do not insist on clear evidence of greater benefit than harm, they are failing in their basic purpose."