A US Senate report this week linked the type II diabetes treatment Avandia with thousands of heart attacks, as the US Food and Drug Administration scrambled to set up hearings on the drug’s safety.

A two-year investigation by the staff of the Senate Committee on Finance found that the drug’s manufacturer, GlaxoSmithKline, knew of the health risks of the drug, but rather than addressing those concerns, tried to discredit the science behind the results. 

Beginning in May 2007, committee staff studied more than 250,000 documents from GlaxoSmithKline, the FDA, and universities related to the drug’s approval studies. The committee investigation was prompted by a study in the New England Journal of Medicine that reported this safety concern.

The pharmaceutical is still on the market, but with an FDA ‘black box’ warning, which is the strictest level required by the FDA.