Hot-melt extrusion-based solid dispersion of aripiprazole: Preparation, characterization, and in vitro evaluation

Background: Aripiprazole (ARI), a biopharmaceutics classification system (BCS) class IV drug, exhibits poor water solubility and low permeability, resulting in limited bioavailability. Addressing these challenges requires innovative approaches to enhance solubility. This study focuses on the development and evaluation of solid dispersions (SDs) of ARI using “hot-melt extrusion,” (HME) a scalable and solvent-free method known for its ability to create stable amorphous structures. Soluplus® (SP) and Kollidon® 30 were employed as hydrophilic polymeric carriers to improve the solubility and stability of the amorphous drug form. Results: SDs were prepared by taking drugs and carriers (SP and Kollidon® 30) in drug: carrier proportions of 1:1,5, 1:2, 1:2.5, and 1:3. This mixture was extruded with a twin-screw extruder operating at screw speeds between 80 and 120 RPM and with heating temperatures ranging from 120°C to 150°C. Characterization by Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy confirmed the transformation to an amorphous state, the absence/presence of significant drug-polymer interactions in physical mixtures/SDs, and enhanced surface morphology. Hot-stage microscopy supported these findings, while in vitro dissolution studies revealed significantly improved drug release profiles. Notably, ARI-SP SDs achieved significantly faster drug release and demonstrated superior stability compared to ARI-Kollidon® 30 SDs. Conclusion: The study highlights the effectiveness of HME in overcoming the limitations of conventional methods for SDs. By leveraging hydrophilic carriers, such as SP and versatile techniques, such as HME, SDs offer a promising strategy for developing pharmaceutical products with enhanced bioavailability.