Leveraging a pulsatile delivery platform to create a single-injection rabies vaccine

Introduction: Rabies is the deadliest viral disease with a nearly 100% fatality rate if untreated; however, post-exposure prophylaxis (PEP) consisting of a vaccine and rabies immune globulin lowers the fatality rate to < 1%. Unfortunately, this treatment requires up to four vaccine doses administered over up to four weeks. Consequently, many do not receive appropriate treatment, resulting in 60,000 deaths annually (1). Herein, we create a single-injection rabies vaccine by engineering antigen-loaded microparticles to release their payloads in discrete pulses that recapitulate a standard PEP dosing regimen.