Two UK pension funds are reportedly fighting to become lead plaintiffs in a US class action suit against GlaxoSmithKline, which accuses the drug giant of issuing misleading statements regarding its diabetes drug Avandia.

A spokesperson for Avon Pension Fund has confirmed to PharmaTimes UK News that it has applied to become a lead plaintiff in the suit, which is seeking unspecified damages for a dive in GSK’s share price following publication of a study in the New England Journal of Medicine that claimed Avandia (rosiglitazone) substantially raises the chance of suffering a heart attack. A spokesperson for North Yorkshire Pension Fund, which is also said to be vying for lead plaintiff status, could not be reached for comment.

The study in the NEJM concluded that patients on Avandia were 64% more likely to die from cardiovascular causes, and raised the likelihood of suffering a heart attack by 43%. There were a total of 158 heart attacks and 61 deaths from cardiovascular causes in patients involved in the studies but the number of rosiglitazone-associated events was small – 86 myocardial infarctions in Avandia patients versus 72 in the controls and 39 cardiovascular deaths versus 22.

But GSK has always defended its drug, previously saying that it “strongly disagrees with the conclusions reached in the NEJM article, which are based on incomplete evidence and a methodology that the author admits has significant limitations”. The firm added: “In contrast to a meta-analysis, the most scientifically rigorous way to examine the safety and benefits of a medicine is to conduct large scale, long-term clinical trials in patients with the disease. Several trials of this type have been ongoing for many years.”

Avandia has been on the market since 1999.