Evaluation of pharmaceutical bioequivalence and anthelmintic afficacy for different albendazole generic formulations in parasitized sheep

Abstract

Albendazole (ABZ) is a broad-spectrum anthelmintic drug widely used in human and veterinary medicine. The aim of this work was to evaluate the bioequivalence and anthelmintic efficacy of four different generic formulations of ABZ in sheep parasitized with resistant nematodes. Fifty parasitized lambs were divided into five groups (n=10): Untreated control and treated groups A (reference), B, C and D. Treated animals received different ABZ formulations (5 mg/kg). Plasma samples were collected over 3 days post-treatment and drug concentrations measured by HPLC. The efficacy of the different treatments was estimated by the faecal egg counts reduction test (FECRT). No bioequivalence was observed between the reference and either B or D generic formulations. The FECRT ranged between 36 and 59%. The study demonstrated a lack of bioequivalence for some of the generic ABZ formulations under study, which are commercially available for use in sheep.