Preparation, Physicochemical Characterization and In Vitro and In Vivo Activity Against Heligmosomoides polygyrus of Novel Oral Formulations of Albendazole and Mebendazole.

Albendazole (ABZ) and mebendazole (MBZ) are the 2 most commonly used drugs in the treatment of soil-transmitted helminth infections in humans, but their performance is hampered by low solubility and physicochemical properties. We developed different formulations (ß-cyclodextrin inclusion complexes, chitosan-based microcrystals (CH), and polyvinyl alcohol and polysorbate 80-based nanoparticles [P80]) of ABZ and MBZ with an improved in vitro solubility profile and tested their activities in vitro and in vivo against the hookworm Heligmosomoides polygyrus. We found that all formulations tested showed a faster and higher dissolution level and were more active than the standard drugs. When compared to ABZ, ABZ-P80 revealed the highest improvement in terms of solubility increase (4-fold increase) and in vivo activity (an ED50 of 7.0 mg/kg for ABZ and of 4.1 mg/kg for ABZ-P80). Although the activity of MBZ was in all cases lower than ABZ, the improved formulations of MBZ performed better than standard MBZ, where MBZ-CH showed a significantly higher in vivo activity (ED50 of 8.02 mg/kg vs. an ED50 of 203 mg/kg for MBZ). In this work, we identified MBZ-CH and ABZ-P80 formulations as lead formulations hence further studies should be conducted.