The European Union's drug regulator down played claims by recent studies that suggested a possible risk with Sanofi-Aventis's widely-used diabetes drug, Lantus and cancer.

Lantus, (insulin glargine) came into the limelight last month after three out of four studies published in the journal Diabetologia suggested an increased risk for cancer, especially breast cancer associated with use of the drug.

However disagreeing with the findings last week Sanofi said at the time the data was of "poor quality" and no firm conclusions could be drawn. They issued a statement prepared by “a multidisciplinary board of renowned international experts” who said the findings were “inconclusive and inconsistent”.

This was followed by the European Medicines Agency who carried out an “in-depth review”, said in a statement on Thursday that the “available data does not provide a cause for concern and that changes to the prescribing advice are therefore not necessary”.

The agency added that "due to methodological limitations, the studies were found to be inconclusive and did not allow a relationship between insulin glargine and cancer to be confirmed or excluded".

It also called on the French drug maker to generate further research on the drug. "In addition, the committee noted that the results of the studies were not consistent."

"This is important and reassuring information for patients receiving Lantus," said Jean-Pierre Lehner, the group's chief medical officer. Sanofi said it would take steps to develop further research in the area.

This followed in the footsteps of the US Food and Drug Administration who at the beginning of the month noted that the duration of patient follow-up in all four studies “was shorter than what is generally considered necessary to evaluate for cancer risk from drug exposure”.

A Lancet online comment by statistician Stuart Pocock of the Department of Epidemiology and Population Health in London on the Diabetologia studies said, “Unnecessary alarm and anxiety” have been created by “claims of harm not backed with adequate evidence”.