Dissolving polymer microneedle patches for influenza vaccination

Sullivan and his colleagues describe a novel microneedle patch-based system for vaccine delivery that targets the skin's antigen-presenting cells, providing improved immunogenicity and eliminating the hazards associated with using hypodermic needles. The group demonstrates the feasibility of this approach for influenza prophylaxis, whereby vaccine is encapsulated within microscopic polymeric needles that dissolve in the skin in minutes. Influenza prophylaxis would benefit from a vaccination method enabling simplified logistics and improved immunogenicity without the dangers posed by hypodermic needles. Here we introduce dissolving microneedle patches for influenza vaccination using a simple patch-based system that targets delivery to skin's antigen-presenting cells. Microneedles were fabricated using a biocompatible polymer encapsulating inactivated influenza virus vaccine for insertion and dissolution in the skin within minutes. Microneedle vaccination generated robust antibody and cellular immune responses in mice that provided complete protection against lethal challenge. Compared to conventional intramuscular injection, microneedle vaccination resulted in more efficient lung virus clearance and enhanced cellular recall responses after challenge. These results suggest that dissolving microneedle patches can provide a new technology for simpler and safer vaccination with improved immunogenicity that could facilitate increased vaccination coverage.