Soluplus® as a solubilizing excipient for poorly water-soluble drugs: Recent advances in formulation strategies and pharmaceutical product features

Since the emergence of Soluplus® (SOL) as a commercial graft copolymer, several publications have been issued on its promising potential as a solubilizing excipient that could promote the dissolution rate and bioavailability of several poorly water-soluble drugs. Numerous drug formulation strategies were embraced for SOL to yield highly bioavailable products, such as solid dispersions (SDs), nanosuspensions, nanomicelles, and self-nanoemulsions. Likewise, the resulting formulations are supposed to improve drugs' physical stability and solubility in biological fluids. SD is regarded as a straightforward approach that was implemented for SOL in drug development research. Several SD strategies, such as hot-melt extrusion, nanoextrusion, supercritical fluid processing, electrospinning, spray-drying, and freeze-drying are superior to other techniques in producing more effective SOL-based formulations. This review recapitulates the most recent literature showing the diversity of the current applications of SOL in the different pharmaceutical formulations, highlighting the available forms of drug delivery systems, and the applicable formulation strategies.