In January 2014 the Western Canadian Association of Bovine Practitioners (WCABP) published an article in Vet Advice about pending change in the use of antimicrobials in livestock production. Although Guidance #213 is a U.S. initiative introduced through the Food and Drug Administration (FDA), its intent is to limit use of antimicrobials in livestock production. Canada will be obliged to follow suit.
FDA’s resoluteness in the matter was clearly stated: “In light of the risk that antimicrobial resistance poses to public health, the use of medically important antimicrobial drugs for production purposes is not justified. Indications like ‘increased rate of gain’ or ‘improved feed efficiency’ will no longer be supported in the approval process when claims involve medically important drugs.”
Guidance #213 provided guidance for drug companies to voluntarily revise FDA-approved labelled use conditions to (a) remove the use of antimicrobial drugs for production purposes; (b) add, where appropriate, scientifically supported disease treatment, control or prevention uses; and (c) making drugs that were available over the counter (OTC), prescription drugs requiring a veterinary prescription for use in livestock production.
The term “production purposes,” as used by FDA, meant use of antimicrobials with the intent of enhancing growth or improving feed efficiency.
Some of the common drugs that will be affected include: oxytetracycline, chlortetracycline, sulfa drugs including sulfamethazine and sulfaquinoxaline, erythromycin, neomycin, tylosin, lincomycin and penicillin.
There were a number of people involved in the livestock industry that doubted how quickly and completely the pharmaceutical industry would come on side. For one, there remained burning doubt that many of the antimicrobials targeted were contributing in any significant way to resistance in human medicine. The lack of definitive proof of resistance was a tool in the hands of the pharmaceutical industry, already a formidable lobby against the indiscretionary use of “precaution” by government, to offset sweeping change.
The FDA requested that animal drug sponsors (those who own the right to market products) voluntarily work with FDA to revise approved use conditions for medically important antimicrobial drug products. FDA assumed a position from the outset that sick animals need treatment, and that the antimicrobial drugs in question should remain available for the purposes of treating, controlling or preventing disease.
The FDA’s request for the pharmaceutical industry to voluntarily comply and collaboratively make application to change label claims, worked. Twenty-five of 26 major sponsors responded. The 25 represented over 99 per cent of total pharmaceutical sales affected by Guidance #213. It’s expected some companies will voluntarily withdraw applications completely and effectively remove these products from sale in the U.S., and probably eliminate their availability in Canada.
Once product labelling is changed, using these products in feed for production purposes becomes illegal. In addition, FDA regulations do not permit extra label use for non-therapeutic purposes.
It is important to note that all products affected by this plan are currently available over the counter (OTC). A key component of FDA’s plan was the transition of affected antimicrobials from their current OTC status to one requiring producers to obtain a prescription or order products through a licensed veterinarian. The FDA believes firmly that any measure of judicious use of medically important antimicrobial drugs in food-producing animals should involve the oversight of licensed veterinarians given the importance of their scientific and clinical training and knowledge.
In the case of prevention, a veterinarian practising judicious use would determine the risk of a specific bacterial disease and whether it would be appropriate to use medically important antimicrobials for prevention purposes. For example, the veterinarian would consider the way the drug acts against the particular bacteria in question, whether it can effectively get to the place of infection, and how long the drug maintains effective levels at the site of infection.
Other important factors veterinarians consider when determining whether a particular drug is appropriate for preventive use include whether: (1) there is evidence that the drug will be effective in treating the particular disease, (2) such preventive use is consistent with accepted veterinary practice, (3) the use is intended to address particular bacteria, (4) the use is appropriately targeted to animals at risk of developing a specific disease, and (5) there are no reasonable alternatives for intervention.
Two significant events within the last year anchored the need for regulatory change and removed any doubt that industry was on side with change. First, was the World Health Organization’s report on global antibiotic resistance. In the words of Dr. Keiji Fukudu, WHO assistant director general for Health Security, “ Unless we improve efforts to treat and prevent infection, and prescribe and use antibiotics we will lose more and more of these global health tools. The implications are devastating.”
The second was a recent publication by the FDA on the pharmaceutical industry’s response to Guidance #213.
In the meantime, Canada dawdles. Repeated attempts to have government agencies associated with drug approvals and feed regulations deal specifically with issues like changing label recommendations related to performance enhancement are slow. The import of active pharmaceutical agents — many unregistered and in the form of pure antimicrobials that eventually find their way into the ration of various livestock species — remains a sore point with groups seeking change. In the same context, persistence of the regulatory loophole that allows producers to import drugs for their own use without products being registered in Canada, is an irritant. Little has come of a petition submitted to the auditor general in September 2012 on behalf of the Ad Hoc Committee on Antimicrobial Stewardship in Canadian Agriculture and Veterinary Medicine related to these shortcomings.
AMR is an emerging crisis. Estimates suggest that antimicrobial resistance directly affects the health outcome of over 2.5 million people in North America every year; over 2,500 die and the cost of resistance may be as high as $40 billion. It’s time to do more. Agriculture has a role.
— Dr. Ron Clarke prepares this column on behalf of the Western Canadian Association of Bovine Practitioners. Suggestions for future articles can be sent to Canadian Cattlemen ([email protected]) or the WCABP ([email protected]).