The U.S. Food & Drug Administration has published its annual report summarizing sales and distribution data for all antimicrobial drugs approved for use in food-producing animals in 2016.

According to FDA, the latest report shows that antimicrobial sales decreased from 2015 to 2016, with domestic sales and distribution of all antimicrobials decreasing by 10% and domestic sales and distribution of medically important antimicrobials decreasing by 14%. In previous years (between 2009 and 2015), overall sales volumes increased annually, FDA said.

In its announcement, FDA emphasized that the 2016 summary report does not reflect changes made under its “Guidance for Industry (GFI) #213,” which transitioned medically important antimicrobials used in the feed or water of food-producing animals to Veterinary Feed Directive marketing status (feed uses) or prescription (water-based uses) and withdrew growth promotion and feed efficiency indications of affected products.

The latest summary report captures data for the 2016 calendar year (January to December 2016), which FDA noted does not account for changes in sales or distribution resulting from implementation of GFI #213 on Jan. 1, 2017.

Furthermore, FDA emphasized that sales and distribution data do not represent the actual use of the products. It is important to acknowledge that these data are sponsor estimates of product sales and are not intended to be a substitute for actual usage data, FDA said. For example, veterinarians and animal producers may purchase drugs but never actually administer them to animals, or they may administer the drugs in later years.

Additionally, the agency said species-specific sales estimates should not be directly compared, because a variety of factors confound direct comparison of species-specific sales estimates, including differences in the animal population size, weight, life span and drug metabolism.

In response to the FDA report, the Animal Health Institute (AHI) said, “Antibiotic sales — whether they go up or down — are not predictors of public health impact. While today’s sales report is an interesting piece of the story, we are more encouraged by the recent data from the National Antimicrobial Resistance Monitoring System that shows that, for those pathogens that might transfer from animals to humans, resistance rates in people have been stable or declining. Over the 20-year life of the program, salmonella resistance in humans has steadily declined. This trend of reduced resistance began long before implementation of FDA’s judicious use program and is evidence that producer supported antimicrobial responsible use programs have been working.”

FDA has published annual summary reports since 2009, in compliance with requirements established by Section 105 of the Animal Drug User Fee Amendments of 2008.

In May 2016, the agency issued a final rule revising its annual reporting requirements for drug sponsors of antimicrobials sold or distributed for use in food-producing animals to obtain estimates of sales broken out by major food-producing species: cattle, swine, chickens and turkeys. FDA noted that the “2016 Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals” is the first annual summary report to include these species estimates. FDA anticipates that having these additional species-specific data will improve the agency’s understanding of sales and distribution data.

Sales data provide insight regarding antimicrobial drugs entering the marketplace, but additional sources of information should be considered when assessing progress of efforts to foster judicious antimicrobial use, including actual usage data, animal demographics, animal health data and data on resistance, FDA added.

AHI said, “Public policy that focuses only on reducing the amount of antibiotic used has not reduced antibiotic resistance rates in humans and can result in more animal disease and death. We will continue to work with customers, veterinarians and other stakeholders to preserve a safe food supply and protect public health through the careful and judicious use of antibiotics to keep food animals healthy.”