Example: Virginiamycin and Synercid
CDER/CVM Criteria for ranking drugs based on “importance”:
Factors related to drug efficacy
1) sole therapy/limited available therapies for treating humans
2) therapy of choice for human infection(s)
3) spectrum of activity of particular importance
4) importance as an oral (rather than parenteral) therapy
5) importance in treating food-borne infections
6) unique mechanism of antimicrobial action
Factors related to development of antimicrobial resistance
7) cross-resistance within drug class
8) cross-resistance across drug classes
9) ease of transmissibility of resistance determinants
10) cross resistance between animal and human drugs