Notice to stakeholders: Update on the post-market re-evaluation of medically important antimicrobials for veterinary use with unspecified or prolonged durations of use

Background

Antimicrobials are essential tools; they support animal and public health and contribute to a safe and secure food supply. However, the use of antimicrobials can lead to the development of antimicrobial resistance (AMR). AMR is a global public health threat and addressing AMR is a shared responsibility among various levels of government, drug companies, health practitioners, producers and animal owners. Because resistance can develop any time antimicrobials are used, it is important that we continue to work collectively on AMR so these drugs can be used when they are needed to protect our health.   

Health Canada’s Veterinary Drugs Directorate (VDD) has taken actions to improve oversight and the responsible use of antimicrobials in animals. Collaboration with stakeholders has been instrumental in advancing both regulatory and policy measures that promote the prudent use of these important drugs.

Re-evaluation framework

In 2020, the VDD published its re-evaluation framework, which was an evidence-based approach to determine whether the specific conditions of use of veterinary antimicrobials important in human medicine, may contribute to AMR. This framework was the foundation to re-evaluate labels of medically important antimicrobials for use in animals with unspecified or prolonged durations of use.

A Notice to stakeholders (2022) outlined the purpose and scope for the review of veterinary antimicrobials, identifying 18 active ingredients (~101 products) for re-evaluation. In 2021 and 2022, stakeholders were engaged on the scope, including discussions on opportunities and challenges to update veterinary product labels during an information session and webinar. A key theme that emerged was the importance of collaboration between the veterinarians and producers, drug companies and the regulator.

Preliminary analysis and communication

From the preliminary analysis of in-scope products:

• a large portion of the products were premixes or soluble powders for oral administration in food-producing animals,
• were of high (Category II) or medium importance (Category III) to human medicine as per VDD’s categorization,
• many products carried indications for the same diseases, and;
• prevention claims often had less defined durations of use.

Notification letters were sent to companies in 2022 identifying veterinary antimicrobial products in their portfolio that had unspecified or prolonged durations of use.

The identified in-scope products include:

• those that were first to market (innovators) and subsequent entry (generics),
• new drugs and not-new drugs, and;
• various indications, species and routes of administration.

The variability across in-scope products make a single approach to re-evaluating these labels challenging. A broader approach is needed where stakeholders, from drug companies to veterinarians, each have a role to play, to ensure product labels align with the prudent use of antimicrobials within a Canadian context, while remaining clinically relevant.

Updating product labels

The VDD has completed the groundwork needed to identify and triage products with unspecified or prolonged durations, where a label change may be required to support prudent use, to align with the current needs and uses of the product.

As the regulator for veterinary drugs, the VDD remains committed to maintaining high standards for new drugs on the market, ensuring appropriate labelling for new products and maintaining access to safe and efficacious antimicrobials.

The VDD is available to provide pre-submission advice to drug companies to identify information needed to support a proposed labelling change to better reflect prudent use and clinical relevance. Once filed to VDD, the submission will be reviewed to authorize the changes to product labelling.

Contact Health Canada's Submission Knowledge Management Division by email at vdd.skmd.so-dgps.dmv.cp@hc-sc.gc.ca.