Pharmacokinetics of tenvermectin in swine, a novel antiparasitic drug candidate—comparison with ivermectin

Tenvermectin (TVM) is a novel 16‐membered macrolide compound isolated and purified from the fermentation broth of genetically engineered Streptomyces avermitilis strain MHJ1011. TVM and ivermectin were administered at the dose of 0.3 mg/kg body weight through a single subcutaneous injection route followed by plasma collectiom and analysis at different time intervals. Plasma concentrations of TVM and IVM were determined by high‐performance liquid chromatography with fluorescence detector. Pharmacokinetic analysis was completed using the non‐compartmental method with WinNonlin™ 6.4 software. TVM is rapidly absorbed after administration with peak plasma concentrations (C (max), 9.78 ± 2.34 ng/ml) obtained within 6–22 h. AUC(0‐last) was 586.86 h·ng/ml ± 121.24 h·ng/ml. The mean elimination half‐life of TVM (T (1/2λz)) was 97.99 h ± 46.41 h. The T (1/2λz) of IVM was 146.59 h ± 22.26 h in the study. The present study showed that subcutaneous administration of TVM at 0.3 mg/kg body weight (BW) in swine is absorbed more rapidly than IVM in swine. Compared to the pharmacokinetic characteristics of IVM, there was little difference in the half‐life of TVM among different individuals. The data will contribute to refining the formulation and dosage regime for TVM administration.