Last week, the Food and Drug Administration finalized a long-awaited guidance document that aims to reduce non-therapeutic uses of antibiotics in livestock production and thereby limit the evolution of drug-resistant bacteria.
As I discussed in a previous post, the use of antibiotics in livestock production is often not for the therapeutic purpose of curing disease, but rather for the purpose of speeding growth or increasing feed efficiency. Current estimates are that livestock production consumes 30 million pounds of antibiotics per year, representing 80 percent of the total volume of antibiotics sold in the United States for any purpose. The FDA policy that allows non-therapeutic uses of antibiotics in livestock has in recent years been subject to intense scrutiny by outside advocates, former FDA officials, government investigators, and judges.
The FDA has now taken action to address these concerns by finalizing industry guidelines that it first proposed over a year ago. Under the guidelines, animal pharmaceutical companies would change the labeling of “medically important” antibiotics in two ways. First, the labeling would no longer list production uses (i.e., growth enhancement and feed efficiency) in the approved uses for the drugs. Second, the labeling would require veterinary oversight for therapeutic uses (i.e., the prevention, control, or treatment of a disease), rather than allowing over-the-counter distribution. These changes in labeling would in turn require changes in agricultural use by virtue of other FDA regulations that prohibit off-label use for production purposes.
While the FDA’s action is a step in the right direction toward eliminating non-therapeutic uses of antibiotics in food animals, there are a few features of its strategy that are worth highlighting as they might significantly limit its impact.
First and foremost, compliance with the guidelines is voluntary. Companies will have 90 days to say whether they plan to sign on, followed by three years to implement the changes. FDA chose a voluntary approach because it believes this to be the fastest way to achieve the greatest degree of progress, as regulatory action would require that the agency proceed on a product-by-product basis. It has therefore worked with animal pharmaceutical companies in developing the guidelines and it says that it has confidence in their support. At the time of the announcement, three major companies—Pfizer, Eli Lilly and Merck—had all signed on to the changes. However, if even a handful of small pharmaceutical manufacturers refuse, they might be able to significantly undercut this progress.
Second, although the guidelines would only allow for the “therapeutic” use of drugs, this term is conceived broadly to include the prevention of disease. The potential problem here is that preventative uses of antibiotics pose the same public health risks as production uses, with which they also have significant overlap. Thus it is possible that some of the indiscriminate uses of antibiotics for production purposes will merely be re-characterized as being for the purposes of disease prevention and continue unchanged. In fact, the FDA’s guidance document explicitly notes that “there could be a therapeutic benefit associated with the production use of a drug,” and that in these situation, “sponsors could wish to seek new therapeutic indications to fill the therapeutic needs of animals.”
Third, although the changes to labeling would require increased veterinary oversight, the FDA has concurrently proposed a change to the regulations that govern veterinary oversight. The proposed rule, which is open for public comment until March 12, would revise the requirements that veterinarians are to follow when authorizing the use of certain animal drugs in feed. Under the current regulations, a veterinarian may only prescribe antibiotics “if a valid veterinarian-client-patient relationship exists.” The proposed rule would replace this with a more general requirement that the veterinarian provide supervision or oversight “in compliance with all applicable veterinary licensing and practice requirements.” Whether this change will take the teeth out of the increased veterinary oversight is something that I hope experts will weigh in on during the notice and comment period.