Study Questions Crestor Safety
Matthew Herper, 05.23.05, 5:40 PM ET
NEW YORK - A new analysis of data reported to the Food and Drug Administration is likely to add to the drumbeat of safety concerns about AstraZeneca's cholesterol-lowering drug, Crestor.
Researchers at Tufts University, writing in the journal Circulation, found that doctors were significantly more likely to report serious muscle, kidney and liver side effects during Crestor's first year on the market than they were for other cholesterol-lowering drugs, such as Lipitor, Zocor and Pravachol. The paper was published in a lightning-fast five weeks, highlighting its importance.
"While this is concerning, it is not definitive," says Steven Nissen of the Cleveland Clinic.
Doctors caution that no patient should just stop taking any cholesterol drug, because the life-saving benefits of the pills have been proven in large, well-designed studies. Richard H. Karas, director of the center for preventative cardiology at Tufts University and who headed up the analysis, says his study actually reaffirms the safety of Lipitor, Zocor and Pravachol, known collectively as statins. Even for Crestor, the rate of side effects is low enough that the benefits of the drug, which is a powerful cholesterol-lowering agent, might outweigh the risks, which are still small. Patients with concerns should talk to their doctors. "Statin drugs are safe," says Karas.
But Karas says, in his opinion, doctors should reserve Crestor for patients who can't get benefits with the other drugs. That represents another problem for Crestor, which has never lived up to the big hopes that preceded its launch in 2003. In the fall, rogue FDA researcher David Graham pointed to Crestor as a drug with potential safety problems. The medicine's share of the $14 billion U.S.-cholesterol market has been stalled for a year. Global sales of Crestor are a mere $1 billion, compared to $11 billion for top-seller Lipitor from Pfizer (nyse: PFE - news - people ).
Crestor is far more potent than Zocor or Pravachol, although its top dose lowers cholesterol in a manner comparable to Lipitor. The drugs are processed by the body in different ways--meaning a patient might tolerate one, but not another.
Writing in an editorial that accompanies the study, Scott Grundy of the University of Texas, Southwestern, pointed out that the FDA had already published its own detailed analysis of Crestor's safety, in response to a petition from the public advocacy group Public Citizen, arguing that the drug should be taken off the market. The FDA concluded that the drug should remain on the market, in an analysis Grundy called "impressive." He does advocate care in administering the statin drugs.
"At the present time, I don't see enough evidence of increased danger...to make any solid recommendation," Grundy said during a teleconference with reporters. Christie M. Ballantyne, a researcher at Baylor College of Medicine says, "It won't change the way I'm treating patients."
Both the current report and Public Citizen's Web site relied on voluntary reports of side effects. It can be difficult to draw conclusions based on these reports, because they are random. There was already controversy about Crestor's safety when it was launched, and doctors may have been more likely to report side effects for it than for the other drugs. These sorts of issues, which came to public attention during the Vioxx issues, can make it difficult to tell whether drugs are safe, even after they have been on the market for years.
"It is a point, as the dust settles, that we have an inadequate system for tracking drug safety," says Karas.
forbes.com |
