Docket Management
Docket: 98D-1146 - Eval. the Safety of Antimicrobial NADs Re. their Microbiological Effects on Bacteria of Human Health Concern
Comment Number: EC -7

Accepted - Volume 2

Comment Record
Commentor Ms. Mary Harris Date/Time 2002-11-26 15:01:46
Organization Pfizer Inc, Animal Health Group
Category Company

Comments for FDA General
Questions
1. General Comments Pfizer Inc, Animal Health Group provides these comments to FDA Docket No. 98D-1146 on CVM draft guidance for industry #152 “Evaluating the Safety of Antimicrobial New Animal Drugs with Regard to Their Microbiological Effects on Bacteria of Human Health Concern”. Pfizer believes that significant progress has been made with the issuance of this draft guidance and appreciates the fact that FDA/CVM have embraced the concept of a qualitative risk assessment approach to address this important concern. This qualitative risk assessment approach represents a significant positive step over the “framework” document concepts originally proposed for evaluating the safety of antimicrobials used in food-producing animals and their effect on bacteria of human health concern. We continue to encourage a science-based open dialogue with all stakeholders on this complex issue as the proposed process is refined to ensure that it will lead to pertinent exposure and consequence assessments. Specific comments on aspects of the document follow: · Ranking of antimicrobial drugs according to their importance to human medicine (Appendix A). We strongly urge FDA/CVM to reconsider the ranking logic as presented in this draft guidance and prioritize the ranking based on the importance of various drugs in treatment of foodborne illness in humans. The ranking as presented in Appendix A provides a rather detailed overview of how antimicrobials, individually or as a class, are used in human medicine and ranks their importance based on these specific uses in humans. However, there is a lack of correlation between this ranking and the ultimate potential consequences to human medicine from use of these drugs in food animals. The ranking for purposes of consequence assessment within the context of GL #152 should be based on the importance of the drugs in treatment of foodborne illness. Although this is one factor included in the current ranking, it is not clear if/how this factor has been weighted in the overall ranking. · Consequence assessment. As noted in the draft guidance, the consequence assessment should describe the relationship between specified exposure to the hazardous agent and the consequences of those exposures. However, the guidance oversimplifies this step of the risk assessment process by assuming a qualitative estimate of the consequences of such exposure can be based solely on the human medical importance of the drug in question. Even if the drug ranking is revised, as suggested in the above comment, this step of the assessment process still needs to be expanded to consider the human medical impact that could result from exposure to bacteria resistant to the drug under review. · Hazardous agent. It is not clear from either the guidance document or from current scientific understanding how one might evaluate the potential risk to human health of exposure to resistance determinants carried by commensal or non-pathogenic bacteria from treated food animals. Without guidance, validated approaches, and evidence that such routes of exposure do, in fact, present some potential risk, we would recommend that the qualitative risk assessment eliminate such organisms from consideration and focus solely on resistant zoonotic pathogens.




EC -7