Long Acting Animal Health Drug Products

Part of the series Advances in Delivery Science and Technology pp 193-220


In Vitro Drug Release Testing of Veterinary Pharmaceuticals

  • Shannon Higgins-GruberAffiliated withMerck Animal Health Email author 
  • , Michael J. RathboneAffiliated withInternational Medical University
  • , Jay C. BrumfieldAffiliated withMerck Animal Health

* Final gross prices may vary according to local VAT.

Get Access


In vitro drug release testing for veterinary pharmaceuticals is a regulatory requirement to aid in the understanding of the in vivo performance of a dosage form. The in vitro release test is used throughout development for formulation and process characterization and post-approval to ensure product quality and therapeutic effect. The current recommended in vitro test equipment and conditions are better suited for mimicking human gastric system physiology but not that of the patients being dosed with veterinary pharmaceuticals. Veterinary dosage forms and delivery systems tend to be more complex and varied because of the diversity of species, size of the animals, and prevalence of unconventional excipients often not used in human health drug products. Therefore, the development of in vitro release tests specific for use with veterinary medicines can be challenging and unconventional with respect to the expectations from the regulatory agencies. Regardless of the analytical approach to development, the final in vitro release test is expected to be ­discriminating with respect to the impact of critical quality attributes on in vivo behavior and easily performed in quality control environments.