Comparative Study of PLGA in-situ Implant and Nanoparticle Formulations of Entecavir; in-vitro and in-vivo evaluation

Abstract Entecavir (Baraclude®) is used daily as a long-term treatment for hepatitis-B virus infections. In this study a sustained injectable biodegradable in-situ implant (ISI) and polymeric nanoparticles (NPs) of Entecavir were prepared using Poly-d,l-lactic-co-glycolic acid (PLGA) polymer and evaluated for their shape, saturation solubility, in-vitro release and in-vivo efficacy. The pharmacokinetic parameters of Entecavir formulations were studied in rats following intramuscular injection, and the data was analyzed using one-way analysis of variance (ANOVA). TEM photographs showed that the ISI had a porous surface after exposure to Sorensen phosphate buffer pH 7.4 for 24 h, and Entecavir loaded NPs had a spherical structure with a smooth surface. The entrapment efficiency of Entecavir NPs was in the range of 47.03–77.84%. The pharmacokinetic studies showed a significant reduction (p