Pharmacokinetics and bioavailability of solid dispersion formulation of tilmicosin in pigs
Nan Zhang, Juan Ba, Shaojie Wang, Zhigao Xu, Fuda Wu, Zhili Li, Hua Deng, Hong Yang
Abstract
Abstract Tilmicosin (TMS) is a semisynthetic macrolide antibiotic restricted to veterinary use but is only partially soluble in aqueous solutions, which limits its administration in treatments. We developed a strategy to enhance the supersaturated solubility of TMS using amorphous solid dispersion (SD). The dissolution profile shown that the dissolution rate of TMS‐SD was obviously faster than TMS. The pharmacokinetics of tilmicosin (TMS) and tilmicosin solid dispersion (TMS‐SD) in pigs after oral administration at a single dose of 50 mg/kg b.w were investigated. The t max of TMS‐SD (2.50 hr) was 1.80 times faster than TMS (4.50 hr) ( p < .05). There were no significant differences in the other PK parameters (C max , t 1/2β , V/F, CL/F, MRT, and AUC 0‐inf ) ( p > .05). The mean relative bioavailability of TMS‐SD compared with TMS was 140.39%, according to the AUC 0‐inf values. These results demonstrated that the solid dispersion technique enhanced the bioavailability of TMS and the new formulation administered to animals via drinking water may be used as a therapeutic alternative for clinical treatments.