The Food and Drug Administration in the US has placed Avandia under scrutiny since 2007  [EPA]

A European drugs watchdog is holding a special meeting to review the safety of Avandia, a widely-used diabetes drug, amid calls for it to be withdrawn because of concerns about heart risks.

The European Medicines Agency (EMA) met in London, the British capital, on Wednesday, two days after UK drug regulators called for product to be pulled from the market.

It said the extraordinary session was necessary because of the complexity of the data being assessed, but will not decide on the drug's future until its next scheduled meeting in late September.

The British Medical Journal (BMJ) and some leading doctors have criticised the response, calling for Avandia to be pulled off the market immediately - saying it should never have been licensed in the first place.

'Multiple problems'

On Monday, Britain's Medicines and Healthcare products Regulatory Agency (MHRA), said Avandia should be pulled from the UK market because of concerns that the drug could increase the risk of heart attacks.

They said an independent panel of experts had advised that the risks of the product outweighed its benefits, and that the drug should no longer be sold in Britain.

The body said it had sent a letter to doctors in July advising them to consider alternative treatments.

Avandia, made by pharmaceutical company Glaxo Smith Kline (GSK), was approved by the EMA in 2000 to help lower blood sugar levels in patients with Type 2 diabetes.

GSK has maintained that its extensive research involving over 50,000 patients has shown that Avandia does not increase the overall risk of heart attack, stroke or death compared to other diabetes drugs.

"We continue to believe that Avandia is safe and effective when it is prescribed appropriately," the company said in a statement.

But the British Medical Journal was critical of both GSK's research methods and the European approval process, outlining what were described as multiple problems associated with Avandia's safety in a report published on Monday.

In the US, the Food and Drug Administration (FDA) has placed Avandia under scrutiny since 2007, when a study suggested that patients taking the drug were 43 per cent more likely to experience a heart attack than those taking other diabetes drugs or no diabetes medication at all.