Poly(hydroxybutyrate) nanoparticle-encapsulated albendazole enhances in vivo efficacy against the Echinococcus multilocularis germinal layer.

Alveolar echinococcosis (AE), caused by the larval stage of Echinococcus multilocularis, is a severe zoonosis requiring prolonged anthelmintic therapy. Albendazole (ABZ) remains the treatment of choice; however, its poor aqueous solubility and low systemic bioavailability limit therapeutic efficacy and necessitate prolonged high-dose regimens. Improving the delivery of existing antiparasitic drugs therefore represents a valuable therapeutic strategy. This study evaluated the in vivo chemoprophylactic and therapeutic efficacy of an innovative nanomedicine formulation comprising ABZ encapsulated in poly(hydroxybutyrate) (PHB) nanoparticles synthesized by electrospraying. The resulting formulation demonstrated high reproducibility, adequate drug loading, and stable physicochemical characteristics suitable for in vivo evaluation. Efficacy was assessed in an experimental murine model of intraperitoneal alveolar echinococcosis using chemoprophylactic and therapeutic protocols. In the chemoprophylactic study, ABZ-loaded PHB nanoparticles significantly reduced cyst weight compared with the untreated control group and induced extensive ultrastructural damage to the germinal layer, outperforming the ABZ suspension. In the therapeutic protocol, the polymeric nanocarrier system significantly impaired metacestode tissue viability relative to the untreated control. Notably, despite the lack of a statistically significant difference in the cyst weights compared to the ABZ suspension, the nanoparticle treatment induced far more pronounced ultrastructural alterations in the germinal layer. This severe damage, characterized by a marked reduction in germinative cells, effectively compromised the regenerative capacity and proliferative potential of the metacestode tissue. In conclusion, the electrosprayed PHB nanocarrier system represents a promising biopharmaceutical strategy to optimize ABZ delivery, enhancing its therapeutic performance against experimental alveolar echinococcosis without requiring increased drug dosages.