Tailoring Physicochemical Properties of Iloperidone by Cocrystallization: Design and Characterization of Novel Cocrystals of Iloperidone and 4- amino Benzoic Acid

Abstract

Background: The current study explores the enhancement of solubility and dissolution rate of a poorly water-soluble drug Iloperidone (IPD) by synthesizing co-crystals (CC) using 4- amino benzoic acid (ABA) as a coformer. Methods: Pharmaceutical CCs of IPD with ABA were designed and synthesized using crystal engi-neering. CCs were prepared by solvent evaporation (SE) technique and studied for their enhance-ment in solubility and dissolution rate. CC formation was confirmed by Fourier Transform Infra-Red Spectroscopy (FTIR), powder X-ray diffraction (PXRD), Differential Scanning Calorimetry (DSC), and Proton Nuclear Magnetic Resonance (1H- NMR). Results: Structural characterization studies exhibited new characteristic peaks, which confirmed that CCs could be generated from IPD and ABA using SE technique. The apparent aqueous solu-bility studies of the CCs exhibited 7.1 folds increase in solubility compared to the pure drug. Im-provement in the rate of dissolution of CCs was evident from the in vitro dissolution studies, where CCs displayed 94.15 ± 0.27% drug release in 60min while pure drug showed only 39.90 ± 1.86% release in the same time period. Conclusion: CCs of IPD and ABA provide a novel approach to overcoming the solubility issues.