May 01, 2004


 Judge sides with FDA on withdrawal of poultry antimicrobial

Posted April 15, 2004

An administrative law judge ordered the withdrawal of the Food and Drug admini-stration's approval for the use of enrofloxacin (Baytril) in poultry, citing potential human health risks. At press time, Bayer Animal Health was planning to submit an appeal.

The outcome of the appeal could bring an end to a three-year dispute between the FDA Center for Veterinary Medicine and Bayer about the safety of using the fluoroquinolone enrofloxacin in poultry. If the drug is withdrawn from the market, there could be a negative impact on human health, and the chicken and turkey industries could lose more than $200 million annually, according to Bayer.

John B. Payne, president and general manager of Bayer Animal Health, said he is disappointed with the judge's decision and feels the human health benefits of the drug were not fully considered.

"This is an extremely complex issue that deserves additional review of the scientific arguments, which we firmly believe support the continued use of Baytril to fight disease in poultry," Payne said. "We will fully examine all of the details in the judge's decision and prepare our appeal accordingly."

Approved by the FDA in 1996, Baytril is used to treat air sacculitis, a pneumonia-like infection in poultry. By Notice of Opportunity for Hearing published in October 2000 and revised in January 2001, the FDA Center for Veterinary Medicine proposed withdrawing approval of the NADA. According to CVM, the proposal was based on a growing body of scientific evidence that the use of Baytril in poultry was contributing to an increase in fluoroquinolone-resistant infections in humans.

Bayer disputed the CVM's conclusions and contended that Baytril is a vital antimicrobial that eliminates serious bacterial infections in poultry. In February 2002, the CVM granted the company's request for a hearing. The hearing was held in front of Judge Daniel J. Davidson, April 28-May 7, 2003.

The Animal Health Institute, an organization that represents the interests of the animal drug industry, participated in the hearing.

In addition to promoting the potential human health benefits of Baytril, Bayer argued there would be a negative impact on animal welfare, the environment, and the economy if the drug were removed from the market.

The judge's ruling, issued on March 16, 2004, found there is a substantial body of evidence supporting the CVM's conclusion that the increase in fluoroquinolone-resistant Campylobacter and resultant campylobacteriosis was caused by the use of enrofloxacin in poultry. Additionally, the judge found that these drug-resistant microbes have the potential to adversely affect human health. The judge also discounted Bayer's claims about the human health benefit of Baytril use in poultry.

According to the ruling: "Baytril is effective in treating E coli infections in broiler chickens and E(scherichia) coli and P multocida infections in turkeys, which leads to less air sacculitis. However, there are alternatives to Baytril. Bayer has not shown Baytril use in poultry to be safe."

Additionally, the judge said the effects of the withdrawal on the economy and animal welfare are not relevant to the case, and that even if they were; the evidence Bayer presented was insufficient.

The complete decision is available on the FDA's Web site,