Warnings added to anti-cholesterol drug Crestor last week sharply understate the drug’s risk, the consumer group Public Citizen said Thursday in a letter to the FDA reiterating its request to have the drug pulled from the market.
Debate over Crestor is set against a backdrop of growing concern over drug safety and comes four years after another cholesterol drug, Baycol, was pulled from the market after being linked to at least 31 deaths from a condition that causes muscle tissue to die.
Public Citizen says its analysis of adverse events reported to the Food and Drug Administration during a yearlong period ended in September linked Crestor to that muscle condition, called rhabdomyolysis, at a rate 6.2 times that of all currently marketed statin drugs combined.
But AstraZeneca (AZN), which makes the drug, said Public Citizen’s report is based on “unscientific information and incomplete analysis.”
Just last week, the FDA approved a new label for Crestor that, while warning of a higher risk in Asian patients, said the drug’s rate of muscle problems among people using the recommended dosages is similar to that of other statins. On Thursday, the FDA said it stood by those comments.
In November, an FDA scientist revived debate over the drug when he told Congress that it was linked to kidney failure and rhabdomyolysis, a statement the agency later distanced itself from.
Sales of Crestor, launched in 2003, have been dampened by Public Citizen’s petition in March 2004 for the FDA to withdraw the drug, and media attention around the congressional hearings into drug safety.
Still, the drug brought in $908 million in sales worldwide last year, according to AstraZeneca’s annual report. U.S. sales were $608 million, and it ranked fifth in total prescriptions in the statin drug category, well behind top players Lipitor and Zocor, according to IMS Health, which tracks the industry.
Physician Sidney Wolfe of Public Citizen says his analysis of adverse-event information given to the FDA by drugmakers, doctors and patients shows 13.1 reports of the muscle damage per million prescriptions of Crestor. All other statins combined had a rate of 2.1 million reports during that same time period.
“Six times higher is not my definition of similar,” says Wolfe, a longtime critic of the FDA.
Still, researchers caution that the data gathered from adverse-event reports are not definitive because the reports are voluntary, may be duplicative and are not independently verified. The reports can be useful, particularly when they spot rare side effects, as warning flags showing a drug may warrant additional study.