More Skeptical Voices Join the Cox-2 Inhibitor Debate

Previewing a wide-ranging government review of Cox-2 arthritis medications, staff reports from the Food and Drug Administration have raised questions about experimental drugs from Merck(MRK) and Novartis(NVS).

The staff reports, issued Friday after markets had closed, could add to arguments that the entire class of Cox-2 inhibitors, which includes Merck's now-withdrawn Vioxx, is suspect and that such drugs should either be banned or sharply restricted.

Such a decision by the FDA would have a significant economic effect on Merck, Novartis and Pfizer(PFE), whose Cox-2 drugs Celebrex and Bextra also will be reviewed by a pair of FDA advisory committees during three days of hearings starting Feb. 16.

"Many questions regarding cardiovascular risk have arisen as a result of these data, such as whether the observed cardiovascular risk is a class effect or is specific to particular drugs within the class," said one FDA staff report.

"Based upon all of the information currently available, many in the public, the scientific community, and FDA have raised questions about whether there should there be continued marketing" of Cox-2 drugs, the report said.

"Is there a patient population for whom the risk is warranted, given the known potential for benefit?" the report continued. "If Cox-2 drugs continue to be marketed, how much and what kind of information is necessary in order to justify the marketing of a new Cox-2 [drugs]?"

Right now, only Bextra and Celebrex are available in the U.S. The FDA has urged doctors to exercise caution in treating patients with COX-2 drugs until the agency can make further evaluations of their safety and efficacy.

The FDA staff, which usually issues reports a day before advisory committee meetings, got a head start on Friday with some comments about the experimental Merck drug Arcoxia and the experimental Novartis drug Prexige. Although these drugs are available in many foreign markets, the FDA has continued to review their makers' applications and seek additional data.