The Food and Drug Administration plans to prohibit the extralabel use in poultry of certain antiviral drugs to preserve their effectiveness for treating or preventing human infection with influenza.
Though the AVMA is supportive of preserving drugs of public health importance, the Association believes that the FDA order is not necessary.
The order would prohibit extralabel use by veterinarians of the adamantane and neuraminidase inhibitor classes of FDA-approved human anti-influenza A drugs in chickens, turkeys, and ducks. These drugs include amantadine, rimantadine, oseltamivir, and zanamivir.
The FDA is not aware of ongoing extralabel use of these human antiviral drugs by U.S. poultry producers, though veterinarians can legally prescribe the drugs under the Animal Medicinal Drug Use Clarification Act. However, under AMDUCA, the FDA also can issue an order prohibiting certain extralabel uses that present a risk to public health.
The World Health Organization, U.N. Food and Agriculture Organization, and World Organization for Animal Health have expressed concerns that use of human antiviral drugs in poultry could lead to the emergence of resistant strains of influenza A—including H5N1 avian influenza virus.
Some strains of influenza A isolated from birds and people have shown resistance to adamantanes. To a lesser extent, strains from humans have shown resistance to neuraminidase inhibitors.
The National Chicken Council and the AVMA affirm, however, that the poultry industry does not use these drugs. In comments to the FDA, the AVMA adds that researchers have not studied these costly human drugs in poultry because of the inherent impracticality of such usage. Furthermore, the AVMA believes that veterinarians recognize the United States is stockpiling these critically important drugs for human use.
The AVMA also points out that drug therapy is not part of the response plan to highly pathogenic avian influenza. Veterinarians with the Department of Agriculture's Animal and Plant Health Inspection Service would respond to the disease in poultry with prompt depopulation, quarantine, and additional surveillance.
The AVMA considered whether the FDA created the prohibition to deter hobby breeders and owners of backyard flocks from seeking antiviral drugs from veterinarians for their fowl. But the FDA prohibition focuses on the large numbers of poultry in commercial operations.
The AVMA also suggests that the FDA, in issuing the order, is depending on news reports that the Chinese may be treating poultry with an amantadine compound that is not legal in the United States.
The full text of the order is available online through the FDA Center for Veterinary Medicine at www.fda.gov/cvm/.
Parties can submit comments on the order to the FDA by May 22 through the Federal eRulemaking Portal at www.regulations.gov, through the FDA Web site at www.fda.gov/dockets/ecomments, by fax to (301) 827-6870, or by mail to Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Room 1061, Rockville, MD 20852. Comments should include the docket number, 2006N-0106.
The FDA order will become effective June 20.