GSK shares slide 5.1% after Avandia linked to CV death risk; firm likely to cut guidance

New study data has linked GlaxoSmithKline's Avandia (rosiglitazone) to significant risk of heart attack and, when the meta-analysis results were reported in the May 21 issue of the New England Journal of Medicine, shares in the UK drug major fell 5.1% to L13.90.

The drug for type 2 diabetes earned GSK $3.26 billion last year in worldwide sales and over six million people have used it since it was launched eight years ago. In the NEJM meta-analysis of 42 studies, Avandia was associated with a significant 43% increase in the risk of myocardial infarction and a 64% rise in the risk of death from cardiovascular causes.

However, the US Food and Drug Administration's safety alert noted that other published and unpublished data from long-term clinical trials of Avandia, including an interim analysis of data from the randomized, open-label RECORD trial and unpublished reanalyses of data from the previously-conducted placebo-controlled DREAM study provide contradictory evidence about the risks in patients treated with Avandia. But the FDA added that Avandia patients, especially those who are known to have underlying heart disease or who are at high risk of heart attack, should talk to their doctor about this new information as they evaluate the available treatment options for type 2 diabetes.