News from the world of cardiology
Publication of a new meta-analysis of observational studies provides further evidence that the glitazone, rosiglitazone (Avandia®, GlaxoSmithKline), increases cardiovascular events compared with pioglitazone. Rosiglitazone was taken off the market in Europe last year, but remains available in the US.
The latest analysis, published online in the BMJ on March 17th 2011, was conducted by a UK group from the University of East Anglia, Norwich. They examined 16 observational studies involving 810,000 patients taking either rosiglitazone or pioglitazone. Results showed that compared with pioglitazone, use of rosiglitazone was associated with a statistically significant increased risk of myocardial infarction, heart failure, and death.
An accompanying editorial suggests that both rosiglitazone and pioglitazone have too many side effects to justify extensive use.
GSK issued a statement in response to the new meta-analysis noting that many of the observational studies included had also been considered by the US Food and Drug Administration, which concluded that, because they were largely dissimilar they should not be pooled into a single meta-analytic estimate. The company adds that definitive conclusions about differences between rosiglitazone and pioglitazone are hard to make in the absence of long-term head to head trials, and it says that it “stands behind the safety and efficacy of Avandia® when used appropriately”.
EU to investigate pioglitazone bladder cancer link
The European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) has also announced it has begun a review of the benefit-risk balance of medications for diabetes containing pioglitazone (Actos®, Takeda) to further explore the signal of a possible increased risk of bladder cancer with the drug. A similar investigation is underway in the US.