GlaxoSmithKline announced that the US Food and Drug Administration (FDA) has approved updated US prescribing information for the thiazolidinediones (TZD) class of medicines used in the treatment of type 2 diabetes. This approval allows GSK to implement changes in the label for Avandia (rosiglitazone maleate) as previously committed.

The label will contain a boxed warning, which increases the prominence of an already existing warning for all medicines in the TZD class on the risk of congestive heart failure (CHF), a well known and well characterized risk in this class of medicine. The boxed warning also will note that TZDs are not recommended in patients with symptomatic heart failure, and that initiation of TZDs in patients with established NYHA class III or IV heart failure is contraindicated.

The contraindications have also been updated regarding initiation of Avandia in patients with Nyha class III or IV heart failure.

Information about CHF has been included in the prescribing information for Avandia since 1999, when the medicine was first approved by the US Food and Drug Administration. Since 2001, US prescribing information for Avandia has included a warning for "Cardiac Failure and Other Cardiac Effects" with a recommendation that use of Avandia be discontinued in patients if their cardiac status worsened.

The changes related to CHF are being implemented on the labels of all rosiglitazone-containing products: Avandia, Avandamet (rosiglitazone maleate and metformin hydrochloride) and Avandaryl (rosiglitazone maleate and glimepiride).