Core-shell microcapsules compatible with routine injection enable prime/boost immunization against malaria with a single shot (2025, Science Translational Medicine)

Low uptake of booster vaccines is a major challenge for immunisation campaigns. A formulation that could deliver both the initial (priming) vaccine and a “self-releasing” booster dose with a single injection would be transformative for vaccinology, saving lives and reducing the strain on healthcare systems.
This study introduces a new microfluidics-based technology that enables delayed delivery of the booster vaccine dose together with the priming dose, in a single injection. Using patented-design microfluidics chip, we encapsulated the R21 malaria vaccine into 60-80 micron sized polymer microcapsules, designed to release their content weeks or months after injection. When given alongside a standard priming dose in mice, the microcapsules triggered strong antibody response, resulting in 85% of the protection achieved by a traditional prime-boost schedule in a mouse model of malaria.