Study of the bioequivalence of drugs for veterinary use «Avecardit» and «Vetmedin S» in the body of dogs

Abstract

This article reflects the results of a pharmacokinetic comparison of the reproducible drug based on pimobendan «Avecardit» with the reference drug «Vetmedin S» when used in dogs. The experiment used a sequential study design. A group of experimental dogs was formed, consisting of 7 animals (6 main and 1 reserve animal). Blood sampling was carried out before administration and after 10, 20, 40 min; 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 10, 12 and 24 hours after drug administration. Key parameters assessed during the study: maximum concentration (Cmax) and time to reach it, area under the concentration-time curve (AUC) of the active substance of the drug in the blood serum of dogs. The article describes the main stages of the experiment, reagents and standard samples, the process of sample preparation of blood serum samples and HPLC-MS/MS analysis, and presents the results of a study of the bioequivalence of the drugs «Avecardit» and «Vetmedin S».The time to reach the maximum concentration of pimobendan (Tmax) in the blood serum averaged 0.67–1 hour for the drug «Avecardit», 1–1.5 hours for the drug «Vetmedin S».Maximum blood serum concentrations (Cmax) of pimobendan were in the range of 53,995–62,873 ng/ml for the study drug and 49,956–61,108 ng/ml for the reference drug. The 90% confidence intervals for the CmaxT/CmaxR and AUC0-tT/AUC0-tR ratios of pimobendan were within the range of 80–125%. The obtained results of the research work, from a scientific point of view, are a sufficient basis for recognizing the pharmacokinetic equivalence of the reproduced drug to the reference one.