By Tara L. Felix
The Food and Drug Administration recently published FDA GFI #191. Some readers may recall discussions of a similar "GFI" (Guidance for Industry) in 2017 when FDA began requiring a veterinary feed directive, or VFD, for antibiotics delivered in feed to production animals. This new guidance has, seemingly similarly, rolled out quickly and without all that much actual guidance.
First of all, the title of the FDA GFI #191 document is "Changes to Approved NADAs – New NADAs vs. Category II Supplemental NADAs." A NADA is a New Animal Drug Application. Any company wishing to market a "drug" to the animal industry must fill out a NADA and submit that NADA to the FDA for approval. The FDA will then review the safety and efficacy of said drug and decide whether or not the company can market the drug with the given label claims. What the company proposes and states on the label, then, becomes critically important.
For example, if a company attempted to get a NADA for an aspirin like drug approved but claimed on the label that aspirin would make every cow have twins, they would have to also submit to the FDA the studies that proved this label claim. Therefore, the process to acquire adequate data to submit with a NADA generally take many years, sometimes as many as 10 years. Label claims have become a crucial component of FDA GFI #191.
While FDA GFI #191 applies to all NADA and any changes to category II supplemental NADA, the larger impact on the beef industry is the fact that all steroid implants used for beef cattle production are considered drugs. While implants are recognized as safe and do not require regular reevaluation, the sticking point here has to do with label claims.
Examples of category II supplement for an NADA would be:
- A change in dose (amount of drug administered per dose).
- A change in the treatment regimen (schedule of dosing).
Because most of the implants on the market are labeled for a specific production setting or phase - for suckling calves, for growing cattle on grass, or for cattle fed in confinement, for example - these labels then restrict those implants to that single phase. In order to get a label that states that an additional implant can be used within that specific production phase, a category II supplemental NADA would need to be submitted to the FDA requesting said label change.
Why does FDA GFI #191 impact cattle producers?
In December 2021, the FDA drafted a letter to stakeholders citing FDA GFI #191. The letter stated that after June 2023, implants that are not expressly labeled for reimplantation will not be able to be placed in cattle more than once per production phase. It was the drafting of the December letter and the redefinition of production phases that have ultimately led to the upcoming potential changes to implant strategies, not FDA GFI #191 alone.
The FDA has defined production settings in such a way that there are potentially three separate phases that would still permit implants to occur multiple times in a calf's life, with the currently approved labels. However, if the cattle are not deemed as being in one of these different phases, reimplantation will not be permitted.
At the time of writing this article, June 2022, only 4 implant products carried reimplant claims that would permit multiple implants in a single production phase: Encore, Compudose, Synovex C, and Synovex S. However, again, if cattle move production phase, they may be given another implant that would be labeled appropriate to that production phase.
One example of this could be: One implant given in the "beef calf phase" (perhaps, Ralgro), one implant in the "growing beef steers/heifers on pasture phase" (perhaps, Revalor-G), and one implant in the "growing beef steers/heifers in confinement fed for slaughter phase" (perhaps, Revalor-XS or Revalor-XH).
Why should we care?
Steroid-based implants have been used in beef cattle production for over 5 decades. They are safe and effective technologies for the beef cattle industry. Implants improve average daily gain (ADG) and feed efficiency (FE). For example, cattle that are implanted have a 10 to 15% increase in ADG when compared with cattle that are not implanted and an 8 to 12% increase in FE. Thus, the use of implants increases the net return per head for beef cattle producers. Economics change depending on the given year; however, most implant strategies return 50 to 100$ per animal on average. Over 90% of all the beef cattle produced in the U.S. are implanted and losing these technologies would greatly impact the efficiency of beef cattle production. This loss of efficiency due to decreased implant use would result in the need for more inputs (feed, water, land, etc.) to produce fewer pounds of beef.
What will the future of implanting look like for cattle producers?
First and foremost, you do not have to change Anything before June 2023. Although it may seem that many cattle producers are JUST hearing that changes to implant protocols may be coming, the reality is that FDA GFI #191 was first released in August of 2020, and in May of 2021 a letter was drafted to inform the industry that implant labels would be under review. Further clarification was added via another letter to stakeholders in December 2021. These documents have provided a period of time for implant manufacturers to change or update their labels if seen fit. As previously mentioned, there are implants (Encore, Compudose, Synovex C, and Synovex S) that carry reimplant labels that will not greatly impact their use. In addition, there are implants that restrict reimplant already (Revalor-XH and Synovex One Grower). However, the majority of implants carry no label claims relative to reimplantation. Therefore, if labels do not change, after June 2023, it is expected that implant products can only be used for reimplant purposes within a single production phase if they are expressly labeled as such.
Work with your Extension team or your implant manufacturer representative to determine more specifically how your operation could be affected by these changes. We have advanced warning of these changes. Use that time to formulate a plan so that you do not lose the edge your implant program gives your operation.Source : psu.edu