Food Safety Magazine, February/March 2012

inition in the draft of medically important antimicrobial drugs. An excerpt from the“Questions and Answers on FDA’s Draft Guidance on the Judicious Use of MedicallyImportant Antimicrobial Drugs in Food-Producing Animals” clears up any misconceptionsof FDA’s position on growth promotion:“Is using medically important antimicrobial drugs to increase production in foodproducinganimals a judicious use?No. FDA thinks that using medically important antimicrobial drugs to increase productionin food-producing animals is not a judicious use.”It is therefore reasonable to infer that the FDA is looking to industry to rein in theuse of medically important antibiotics for growth promotion/feed efficiency purposes.To evaluate antimicrobial resistance associated with antimicrobial drugs used in foodproducinganimals, FDA relies on the current approach outlined in the Guidance forIndustry (GFI) 152, “Evaluating the Safety of Antimicrobial New Animal Drugs withRegard to Their Microbiological Effect on Bacteria of Human Health Concern.” GFI152 recommends several measures to reduce the risk of antibiotic resistance.Risk Analysis—Lack of ResourcesGuidance 152 lays out a risk analysis methodology and the recommended processfor evaluating antimicrobial drugs for use in food animals as they have the potential tocause antibiotic-resistant illnesses in humans. Considered in the risk-ranking schemesare food consumption and food contamination data, as well as the duration of druguse and its intended administration, be it on individual, select or entire flocks or herdsof animals. Out of scope of the guidance are the concerns over residues in food of animalorigin. 6 Instead, it focuses on the potential that antimicrobials used in food animalscontribute to the emergence of antibiotic strains of foodborne bacteria. “TheFDA believes that human exposure through the ingestion of antimicrobial-resistantbacteria from animal-derived foods represents the most significant pathway for humanexposure to bacteria that have emergedor been selected as a consequence of antimicrobialdrug use in animals.” 7Perhaps the most important componentof GFI 152 is found in the Appendix,where antimicrobial drugs areranked Critically Important, Highly Importantor Important, according to theirsignificance in human medicine. 7 Antimicrobialdrugs that are approved foruse in animals are marketed as prescriptions(Rx), over the counter or under veterinaryfeed directive. FDA asserts thatfor certain antimicrobial drugs, veterinarysupervision is essential in ensuringjudicious, and safe, use.The guidance describes some examplesof risk management steps, and howsteps might be applied to manage estimatedrisk levels. Three categories (1, 2and 3) are given to associate the overalldrug risk estimation (high, medium orlow). In general, Category 1 includesthose drugs ranked “high” in the risk estimation,Category 2 includes thoseranked “medium” and Category 3 as“low.”Researched & designed by Stanley E. Rutledge fromSTOP based on information compiled by KAW.A Timeline of Antibiotic Regulation40 F O O D S A F E T Y M A G A Z I N E