Bioavailability and Bioequivalence in veterinary drugs- The European issue

Bioequivalence (BE) studies are scientifi c methods that allow comparison of diff erent medicinal products containing the same active substance, or diff erent batches of the same medicinal products or, in a broad sense, diff erent routes of administration of the same product. In Veterinary Medicine, this issue can involve a dual aspect: i) the eff ectiveness of the drug in patients (animal) and ii) the consumers’ health (human). High effi ciency in the fi eld of Veterinary Medicine, particularly in animal production (globally requested for the food supply), is achieved nowadays by the employment of veterinary medicines and feed additives. Because of the lower cost of development and competition in the market place, generic drugs usually sell for less than the brand name drug products from the original manufacturers (innovators or pioneers). Th is fact has led many to believe that generic drugs are somehow inferior to brand-name products. Th e use of animal health products in animal production however, should be done following the standards on Good Clinical Practice (GCP) on Veterinary Drugs Use. Th us, only products approved for food producing animals use and their generic formulation (that have statistically proven BE) should be employed. Several problems concerning peculiar routes of administrations, variability among the subjects, etc…, have been recovered in veterinary drugs rather than the human drugs, for the assessment of the BE. Th e new EU guidelines report narrow rules on BE determination, but lack of rigid rules on excipients. Anyhow, EMEA mandates that the generic veterinary drugs must be as safe and eff ective as the brand-name drugs.