Cyclodextrin Complexation of Meclizine Hydrochloride and its Influence on the Solubility for its Repurposing

Background and Objective: Meclizine (MCZ) is a Biopharmaceutical Classification System (BCS) class-II drug, which is a poorly water-soluble drug along-with very slow-onset of action. In this study MCZ was complexed with different cyclodextrins (CDs), like, sodium sulfobutylether β-CD (SBEβCD), hydroxypropyl β-CD, randomly methylated β-CD, and methyl β-CD, to enhance its solubility for repurposing of this drug for the treatment of infectious diseases and cancer. Methods: Phase solubility experiments were performed to determine the pattern of MCZ solubilization. Characterization of MCZ-CD complexes were done by Fourier transform infrared (FTIR), X-ray powder diffraction analysis (XRPD) and differential scanning calorimetry (DSC). Results: The FTIR, XRPD and DSC studies clearly revealed the formation of inclusion complexes between MCZ and CDs. Phase solubility results showed that MCZ solubility increased linearly with CD at lower concentration, then get saturated in higher concentration, indicative of an AN type solubility profile. Aqueous solubility of MCZ was enhanced upto 8-16 folds through CD inclusion complexation. Conclusion: These complexation studies confirms the results of molecular modeling in which hydroxy and methyl-substituted CDs revealed the higher inclusion as compared with sulfobutyl substituted CDs.