US regulators have been advised by a panel of experts to insist that studies on new diabetes treatments need to include much more data on the potential heart risks of the treatments.

The US Food and Drug Administration’s Endocrinologic and Metabolic Drugs Advisory Committee has voted 14-2 to recommend that pharmaceutical firms must carry out a long-term study of cardiovascular effects or provide equivalent evidence to rule out what the panel calls an unacceptable risk of heart problems. Such studies would need to last as long as five years to detect heart attacks, strokes etc, said a number of panel members, while a number of them endorsed the idea of completing such studies after a drug reaches the market.

The two-day meeting heard from a non-voting panel member, Steven Nissen of the Cleveland Clinic who said that “merely lowering blood glucose levels in diabetes is too simplistic. We must reduce the complications of diabetes, including cardiovascular disease”. Dr Nissen was the author of the controversial meta-analysis published over a year ago in the New England Journal of Medicine which claimed that users of GlaxoSmithKline’s Avandia (rosiglitazone) experienced increased cardiovascular risks.

These latest recommendations are unlikely to go down well with the pharmaceutical firms who are developing new treatments for diabetes as they would inevitably led to more studies and increased costs. However John Jenkins, director of the FDA's Office of New Drugs, said that it involves “a shift in expectations of what we are asking for”. It is a higher level of assurance, he said, “that you've excluded cardiovascular risks."

Panel member Clifford Rosen, an endocrinologist at the Maine Center for Osteoporosis, acknowledged that “although it might be a little more burdensome...we need more studies". The FDA will decide what restrictions are to be put on drugmakers soon and it usually follows panel recommendations.