Improvement of Antialveolar echinococcosis efficacy of novel Albendazole-Bile acids Derivatives with Enhanced Oral Bioavailability

Abstract

Alveolar echinococcosis (AE) is a chronic and fatal infectious parasitic disease, which has not been well-researched. Current recommended therapies for AE by the World Health Organization include complete removal of the infected tissue followed by two years of alben-dazole (ABZ), administered orally, which is the only effective first-line anti-AE drug. Unfortu-nately, in most cases, complete resection of AE lesions is impossible, requiring ABZ administration for even longer periods. Only one-third of patients experienced complete remission or cure with such treatments, primarily due to ABZ’s low solubility and low bio-availability. To improve ABZ bioavailability, albendazole bile acid derivative (ABZ-BA) has been designed and synthesized. Its structure was identified by mass spectrometry and nuclear magnetic resonance. Its physicochemical properties were evaluated by wide-angle X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and polar-izing microscopy; it was compared with ABZ to assess its solubilization mechanism at the molecular level. To avoid the effects of bile acid on the efficacy of albendazole, the inhibitory effect of ABZ-BA on protoscolex (PSCs)s was observed in vitro. The inhibitory effect of ABZ-BA on PSCs was evaluated by survival rate, ultrastructural changes, and the expression of key cytokines during PSC apoptosis. The results showed that ABZ-BA with 4-amino-1-butanol as a linker was successfully prepared. Physicochemical characterization demonstrated that the molecular arrangement of ABZ-BA presents a short-range disordered amorphous state, which changes the drug morphology compared with crystalline ABZ. The equilibrium solubility of ABZ-BA was 4-fold higher than ABZ in vitro. ABZ-BA relative bio-availability (Frel) in Sprague-Dawley (SD) rats was 26-fold higher than ABZ in vivo. The inhibitory effect of ABZ-BA on PSCs was identical to that of ABZ, indicating that adding bile acid did not affect the efficacy of anti-echinococcosis. In the pharmacodynamics study, it was found that the ABZ-BA group had 2.7-fold greater than that of Albenda after 1 month of oral administration. The relative bioavailability of ABZ-BA is significantly better than ABZ due to the transformation of the physical state from a crystalline state to an amorphous state. Furthermore, sodium-dependent bile acid transporter (ASBT) expressed in the apical small intestine has a synergistic effect through the effective transport of bile acids. Therefore, we concluded that the NC formulation could potentially be developed to improve anti-AE drug therapy.