FDA Prepares to Approve Bovine Drug, Despite Protests

Doctors and Health Organizations Say it Could Lead to Ineffective Drugs for Humans

The Food and Drug Administration is poised to approve a new drug - cefquinome - for use in treating cattle suffering from a pneumonia-like disease, in spite of massive protests against it by the American Medical Association and other health groups. They warn that giving animals the drug would speed the spread of microbes resistant to that class of antibiotic. Those microbes could then spread to people, potentially rendering the entire class useless.

Agreeing with those concerns, last fall the advisory board of the FDA rejected a request by a Delaware company to market the drug. But all indicators suggest the FDA will approve the drug this spring. Behind the about-face is a recently-written "guidance document" that is used to weigh threats to humans against benefits of newly-proposed drugs for animals.

According to the "Guidance for Industry 152," unless a new drug is likely to lessen the effectiveness of an antibiotic crucial to fighting food-borne illnesses in humans, the new drug will likely be approved. The potential problem with cefquinome is that it may lessen the effect of the human drug, cefepime. The FDA, however, does not consider cefepime to be a frontline drug, so the risk is not considered under Guidance 152.

This is part of the problem, say those trying to stop the marketing of the cattle drug. "The industry says that 'Until you show us a direct link to human mortality from the use of these drugs in animals, we don't think you should preclude their use,'" said Edward Belongia, an epidemiologist at the Marshfield Clinic Research Foundation in Wisconsin. "But do we really want to drive more resistance genes into the human population?"

Critics point to two drugs previously used in poultry in the 1990s. Human doctors soon encountered a strain of campylobacter resistant to drugs. When dozens of cases of this diarrheal disease started appearing, the FDA sought to ban the poultry drug. Abbot Laboratories, which produces SaraFlox, pulled its product, but Bayer, the maker of Baytril, did not.