A Regimen Compression Strategy for Commercial Vaccines Leveraging an Injectable Hydrogel Depot Technology for Sustained Vaccine Exposure

Equitable global access to vaccines requires overcoming challenges associated with complex immunization schedules and their economic burdens that hinder delivery in under-resourced environments. The rabies vaccine, for example, multiple immunizations effective protection each dose is cost prohibitive, therefore inaccessibility disproportionately impacts low- middle-income countries. In this work, an injectable hydrogel depot technology sustained of commercial inactivated virus developed. a mouse model, it shown single hydrogel-based vaccine elicited comparable antibody titers standard prime-boost bolus regimen despite these comprising only half the total delivered control. Moreover, similar antigen-specific T-cell responses neutralizing compared vaccine. Notably, demonstrated while addition potent clinical Toll-like receptor 4 (TLR4) agonist adjuvant gels slightly improved binding responses, inclusion virion detrimental responses. Taken together, results suggest hydrogels can enable compression dose-sparing strategy improving vaccines.