No Black Box for Crestor

The Food and Drug Administration on Wednesday told physicians to be more judicious in prescribing AstraZeneca's(AZN) cholesterol-fighting drug Crestor.

The agency's advisory included some revisions in the drug's label, telling doctors to start some patients at lower doses and to check for certain medical conditions before prescribing the drug.

Some critics wanted more. The consumer group Public Citizen urged that Crestor be banned. Crestor's foes alleged the drug causes more dangerous side effects, such as a rare muscle-damaging disease called rhabdomyolysis, than similar cholesterol-lowering drugs.

But the FDA said that "Crestor, like all statins, has been associated with a low incidence" of this muscle damage. Statins are the class of drugs that include Lipitor from Pfizer(PFE), Zocor from Merck(MRK) and Pravachol from Bristol-Myers Squibb(BMY).

Data from clinical trials and postmarketing safety reports "indicate that the risk of serious muscle damage is similar with Crestor compared to other marketed statins," the FDA said.

The agency also said it "could not confirm that recommended doses of statins, including Crestor, can cause or worsen kidney failure."

The FDA concluded that the potential benefits of all statin drugs, when used properly, "outweigh the potential risks."

The news apparently softened the blow of the stronger label warnings. AstraZeneca's stock slipped 11 cents to $39.91 on trading volume that was about twice the daily average for the past three months.

"Post-marketing data for Crestor has been thoroughly reviewed over the past year and this labeling revision is the result of that analysis," said David Brennan, president and CEO of AstraZeneca's U.S. operations. "The revisions that the FDA has approved provide physicians with further clarification on how best to use Crestor with their patients. We continue to believe that Crestor is safe and effective when used according to the prescribing information."