For years, beef packers have employed a variety of post-harvest interventions to reduce contamination of meat with E. coli O157:H7 or other shiga toxin- producing E. coli (STEC). Meanwhile, the industry continues to explore options for pre-harvest interventions to reduce the amount of STEC cattle carry into processing plants, thereby enhancing the efficacy of plant interventions.

Toward that goal, the FDA’s Center for Veterinary Medicine (CVM) this week issued a draft guidance outlining appropriate research protocols for companies developing such interventions. Draft Guidance for Industry #229, titled “Evaluating the Effectiveness of New Animal Drugs for the Reduction of Pathogenic Shiga Toxin-Producing E. coli in Cattle,” provides recommendations on study design and criteria drug manufacturers should use when evaluating the effectiveness of animal drugs intended to reduce STEC. The draft guidance addresses topics including:

·         Protocol development

·         Study conduct

·         Animal welfare

·         Nutritional content of experimental diets

·         Assessment of drug concentrations in experimental diets

·         Experimental parameters

·         Substantial evidence of effectiveness.

The draft guidance provides recommendations for acceptable indications, as well as study designs and analyses to verify the effectiveness of drugs intended to reduce pathogenic STEC in cattle. It also potential for STEC pathogens to eventually develop resistance to such drugs, and provides recommendations for companies to include an assessment of resistance potential in their study designs.

 The FDA is accepting public comments on this draft guidance beginning on February 24, 2015. To submit your comments electronically to the docket, go to and type FDA-2015-D-0235 in the search box.

The comment period will close 60 days after it publishes in the Federal Register. While comments are welcome at any time, you should submit them by the closing date for the FDA to consider your comments in drafting the final guidance.

For more information on the draft guidance and on submitting comments, visit the FDA/CVM website.