Hydrogel and nanoparticle carriers for kidney disease therapy: trends and recent advancements

Achieving local therapeutic agent concentration in the kidneys through traditional systemic administration routes have associated concerns with off-target drug effects and toxicity. Additionally, kidney diseases are often accompanied by co-morbidities in other major organs, which negatively impacts drug metabolism and clearance. To circumvent these issues, kidney-specific targeting of therapeutics aims to achieve the delivery of controlled doses of therapeutic agents, such as drugs, nucleic acids, peptides, or proteins, to kidney tissues in a safe and efficient manner. Current carrier material approaches implement macromolecular and polyplex hydrogel constructs, prodrug strategies, and nanoparticle (NP)-based delivery technologies. In the context of multidisciplinary and cross-discipline innovations, the medical and bioengineering research fields have facilitated the rapid development of kidney-targeted therapies and carrier materials. In this review, we summarize the current trends and recent advancements made in the development of carrier materials for kidney disease targeted therapies, specifically hydrogel and NP-based strategies for acute kidney disease, chronic kidney disease, and renal cell carcinoma. Additionally, we discuss the current limitations in carrier materials and their delivery mechanisms.