A drug company urged the government Wednesday to dismiss a petition to ban the new anti-cholesterol drug Crestor, arguing there's no evidence it is riskier than its competitors.
AstraZeneca said initial reports that a 39-year-old woman died of a muscle-destroying side effect of Crestor were false. A later autopsy instead declared her death a heart attack due to long-standing cardiovascular disease.
"The safety and efficacy of Crestor are well-documented," AstraZeneca said in documents filed with the Food and Drug Administration.
The company insisted there's no evidence that Crestor users are at higher risk of the rare but life-threatening muscle condition rhabdomyolysis than users of other cholesterol-lowering statin drugs _ a risk it put at one in 10,000 patients.
AstraZeneca said the controversy is confusing patients and doctors and harming sales, citing a 6.8 percent drop in new prescriptions following publicity about the requested ban last month.
The consumer advocate pushing for the ban, Public Citizen's Dr. Sidney Wolfe, responded that he would continue to do so. He cited FDA documents showing 37 U.S. rhabdomyolysis cases among Crestor users have been reported to the agency since last summer. At least 15 of those people reportedly took the usual 10-milligram starting dose, he said.
It's not clear yet how many of those reported cases actually are linked to Crestor, Wolfe acknowledged. But "it's clearly higher than the other statins," he said.
Side-effect reports aren't proof of a problem, AstraZeneca stressed. But the FDA does analyze them in determining whether a drug may pose more risk than initially determined.
FDA officials wouldn't say Wednesday how many true cases of rhabdomyolysis it has counted, because that analysis isn't finished. So far, "we are not seeing a signal that alarms us," said the FDA's Dr. David Orloff.
Patients using any statin should be aware of the risk and tell their doctors if they have such symptoms as muscle pain or weakness, he added.
Rhabdomyolysis is caused by a breakdown in muscle fibers that end up circulated in the body. Those fibers can be toxic for kidneys and can cause them to fail.
The condition is very rare but prompted another statin, Baycol, to be pulled off the market in 2001 after dozens of deaths worldwide.
Crestor generated concern when, during research studies, some cases of rhabdomyolysis occurred in patients taking 80-milligram doses. The FDA approved Crestor's sale anyway, calling it important because it appeared slightly more potent than other statins. But the FDA warns doctors not to prescribe a dose higher than 40 milligrams _ and to start patients on 5- or 10-milligram doses.
Some doctors complain the controversy is hurting patients' efforts to lower their cholesterol, a far bigger risk than the muscle condition.
"A lot of people got scared," said Dr. Marvin P. Matlock, a Fresno, Calif., physician who said several dozen of his patients quit Crestor without even telling him _ until he spotted their cholesterol rising and persuaded them to resume.
"Ethically, the only drug I can really prescribe now would be Crestor," said Matlock. He switched himself from top-selling Lipitor to Crestor, too, but prescribes only the 10-mg dose. He has since become a paid speaker for AstraZeneca.
On the other side is Dr. Thomas Graboys of Boston's Lown Cardiovascular Center, who won't prescribe Crestor until the safety question is settled. Other statins have longer track records, so there's no need to take the chance, he said.
"We need time to determine what's real and what isn't," Graboys said.
And while AstraZeneca says most insurance will cover Crestor, some companies are blocking it.
"We experienced firsthand the debacle of Baycol," explained Robert Seidman, chief pharmacy officer for California-based WellPoint Health Networks, which has implemented a range of restrictions on Crestor coverage until the issue is settled.
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On the Net:
AstraZeneca: http://www.astrazeneca-us.com/