The US Senate’s Finance Committee has claimed that GlaxoSmithKline (GSK) knew that “there were possible cardiac risks associated with Avandia” (rosiglitazone) for several years before a 2007 study in the New England Journal of Medicine showed a link between the drug and heart attacks.

The committee released a 342 page report on Saturday 20 February. It said the company should have warned patients and the Food and Drug Administration. “Instead,” the report says, “GSK executives attempted to intimidate independent physicians, focused on strategies to minimize or misrepresent findings that Avandia may increase cardiovascular risk, and sought ways to downplay findings that a competing drug might reduce cardiovascular risk.” It says that another drug, pioglitazone (Actos), might pose less risk to patients.

Rosiglitazone, a thiazolidinedione, is used to treat type 2 diabetes. It helps control blood sugar concentrations by increasing sensitivity to insulin. It is marketed in the United …