FDA doctors defend agency's Vioxx moves

WASHINGTON -- Two US regulators defended the Food and Drug Administration's handling of the withdrawn painkiller Vioxx, disputing the contention of heart researcher Dr. Eric Topol that the agency could have forced Merck & Co. to do more safety testing.

The New England Journal of Medicine today will publish two letters from the FDA doctors and Merck physicians responding to an Oct. 21 article by Topol, the Cleveland Clinic's chairman of cardiovascular medicine. Topol had written that the FDA "never took the initiative" to order safety tests on Vioxx before Merck withdrew the medicine Sept. 30 because of heart risks.

Members of Congress and researchers are questioning why the FDA didn't force Merck to study Vioxx's heart risk sooner. The federal Food, Drug and Cosmetic Act gives the FDA power to compel companies to study perceived risks of approved medicines, said Peter Barton Hutt, who served as the agency's chief counsel from 1971 to 1975. Since leaving the agency, Hutt has worked at law firm Covington & Burling, representing clients such as Pfizer Inc.

Merck withdrew Vioxx after a study of the drug as a possible cancer preventative revealed that it doubled the risk of heart attack or stroke in patients taking the medicine for more than 18 months.

"Dr. Topol shows a lack of understanding of the FDA's regulatory authority," FDA doctors Lourdes Villalba and James Witter wrote in their letter. "The FDA cannot 'mandate' post-marketing clinical trials."

Kathleen Quinn, an agency spokeswoman, said the FDA cannot tell a company to conduct additional studies. The agency can tell a drug maker that it intends to begin the administrative process required to remove an unsafe drug from the market, she said.

Topol will publish an editorial in the Jan. 19 edition of the Journal of the American Medical Association, asking for legislation to make it easier for the FDA to compel companies to conduct new studies. The journal on Tuesday released that editorial online.