SOLID DISPERSION TECHNIQUES FOR POORLY SOLUBLE DRUGS: A COMPREHENSIVE REVIEW

The low aqueous solubility of many new chemical entities, especially those of BCS Class II and IV, which results in low and unpredictable oral bioavailability, is still a significant impediment to the successful development of many new chemical entities. Solid dispersion technology has also been used as an effective method to overcome these constraints through dispersing such poorly soluble drugs into hydrophilic carrier matrices to improve dissolution, solubility and therapeutic performance. The basic principle, classification, and the mechanism of solubility improvement in solid dispersions, which are particle size reduction, enhanced wettability, and amorphization of drugs, will be discussed in this review. The traditional techniques of preparing fuse, solvent evaporation, and kneading are contrasted with the new and modern ones including hotmelt extrusion, spray drying, supercritical fluid processing, electrospinning, and freeze drying. The considerable importance of the choice of the carrier, especially polymers (PVP, HPMC, PEGs, poloxamers, Eudragits), is pointed with an emphasis on their optimal characteristics and contributions. All-encompassing characterization methods including solid-state analysis, morphology, and dissolution behavior are described in order to guarantee quality and stability of the product. The uses in different dosage forms, regulatory and manufacturing issues and marketed products summaries are also provided. Lastly, the existing constraints and opportunities of the future such as innovative carriers, green processing technologies, and AIintelligence formulation design are discussed. All in all, solid dispersion technology still holds a colossal promise of the formulation of robust, patient-centric formulations of poorly soluble drugs