The Response of the FDA to Antibiotic Resistance Due to Overuse in Food Animals

The FDA has been watching the problem of antibiotic resistance due to the rampant use of antibiotics on farm animals for many decades. Nonetheless, the agency had yet to take any formal action until very recent years.

The FDA approved the use of antibiotics for growth promotion and feed efficiency—subtherapeutic uses in the 1950s by issuing New Animal Drug Applications (NADAs) for penicillin and tetracyclines. Since then, animal drugs have been widely used in feeding food-producing animals, such as cattle, swine, and chickens. In the 1960s, the FDA sensed the risks to human and animal health posed by the subtherapeutic use of antibiotics on farm animals. In 1970, the agency began a study on the risks linked to the use of antibiotics. The Bureau of Veterinary Medicine (BVM) of the FDA, with assistance from the National Advisory Food and Drug Committee (NAFDC), was responsible for data review and research for several years. Through the recommendations of the NAFDC, the director of the BVM concluded the following:

on the basis of new information before him with respect to these drug products, evaluated together with the evidence available to him when they were originally approved, that the drug products are not shown to be safe under the conditions of use prescribed, recommended, or suggested in their labeling. The evidence, in fact, indicate[d] that such penicillin use may be unsafe, particularly if the higher or therapeutic levels of penicillin should be used as substitutes for the levels currently used subtherapeutically.^[32]

The director thus decided to engage in the process of withdrawing approval of growth-promoting uses of certain antibiotics by issuing notices of an oppor­tunity for hearing (NOOHs) in 1977. In the notices, the FDA confirmed the finding that the use of antibiotics in livestock promotes the development of antibiotic-resistant bacteria, which was transferred “from animals to humans as a result of direct human-animal contact, the consumption of contaminated food, and the widespread presence of resistant bacteria in the environment.”^[33]

Yet, from the 1970s to the late 1980s, other medical institutions failed to fully endorse the finding of the FDA. Both the National Academy of Sciences (NAS) and the Institute of Medicine, a unit of the NAS, held a relatively con­servative position toward the transmissibility of antibiotic resistance between food-producing animals and humans.^[34]

Phasing Out Antibiotics in Food Animals 17

Despite the confirmation and release of the notices, the FDA has yet to hold any hearings on the proposed withdrawals.

After an almost 35-year delay in the withdrawal process, on June 28, 2010, the FDA finally announced a novel approach to address the problem in draft Guidance No. 209.^[36] The agency demonstrated its efforts to phase out certain antibiotics used in farm animals not by a method of coercion but by persua­sion, which encouraged drug manufacturers to voluntarily phase out their use. Consequently, shortly after the release of the draft, on December 16, 2011, the FDA rescinded the 1977 NOOHs.^[37]

In December 2013, the FDA provided more concrete recommendations for drug manufacturers to remove the labeling of antibiotics for growth promo- tion.^[38] FDA officials believe that voluntary participation “is the fastest, most efficient way to make these changes.”^[39]

To facilitate surveillance and monitoring of antimicrobial use and resist­ance, the FDA has required antimicrobial drug sponsors to annually report the amounts of antimicrobial drugs sold or distributed for use in food-producing species during the prior year.^[40] According to a recent survey, it appears that the FDA policy has been working. The data released by the FDA shows that the amount of medically important antibiotics sold for use in food-producing animals in the U.S. has declined, although its use still increased during a certain period.^[41]

IV.