Questions - 1999 VMAC
1. FDA’s goal is to protect the public health by ensuring that the efficacy of human antimicrobial therapies is not compromised due to use of antimicrobials in food animals, while providing for the safe use of antimicrobials in food animals.
Do the concepts laid out in the document entitled, "A Proposed Framework for Evaluating and Assuring the Human Safety of the Microbial Effects of Antimicrobial New Animal Drugs Intended for Use in Food-Producing Animals" provide a sound scientific basis for achieving this goal, if implemented?
2. Categorization of Antimicrobial Drugs for Human Medicine (see Pp. 8-11 and 14 of the Framework Document):
The agency is proposing that the categorization of antimicrobial drugs for human medicine take into account the usefulness of the drugs in both foodborne disease and non-foodborne infectious diseases, when evidence exists that use of the drug may result in induction of resistant pathogens or the transfer of resistant elements to human pathogens. This approach recognizes not only the well known risk of resistance transfer through classical food borne pathogens but also the threat of transfer of resistant bacteria or resistance genes from other intestinal bacteria of food animals resulting in resistant infections of humans with other types of pathogens (e.g., resistant E. coli or Enterococcus). Does the committee agree with this approach?
3. Monitoring Threshold Levels (see Pp. 15-16, 18 and 20 of the Framework Document):
A) Should multiple monitoring threshold levels be established and should they be based on animal data, human data or both? Should the levels be tied to specific actions, e.g., need for further investigation, need for mitigation strategies, need for withdrawal of product from the market?
B) What organism(s) should be the basis for the monitoring thresholds? In the interest of cost containment, should a sentinel organism(s) be designated or should a foodborne pathogen(s) be used?
4. Resistance Threshold Levels (see Pp. 14-16, 18, and 20 of the Framework Document):
The Agency has proposed the creation of different levels of resistance transfer to humans that would be acceptable based on the importance of the drug or drug class in human medicine. Category I antimicrobial drugs would require that use in food producing animals results in little or no resistance transfer to humans. Category II antimicrobial drugs would require that a pre-defined level of maximum resistance transfer be established prior to approval that would depend on several factors, such as the existence of alternatives to the drug, the human pathogen(s) of concern, etc. The level of resistance transfer must be low enough that there is a reasonable certainty of no harm to humans associated with the use of the product in food animals. What criteria should the Agency use to safely define the acceptable level of resistance transfer, if any, for antimicrobial drugs that fall into Categories I and II?
5. On-farm post-approval monitoring programs will be necessary for certain antimicrobials (Category I, Category II/H and some Category II/M products) (see Pp. 17, 19, and 20 of the Framework Document).
Should on-farm monitoring be instituted immediately post approval or triggered by a change in data generated from other sources such as NARMS?