Could Microarray Patch Vaccines Contribute to Pandemic Preparedness? Opportunities, Implementation Considerations, and Priorities

Microarray patches (MAPs) demonstrate potential to improve pandemic preparedness by supporting rapid and large-scale vaccine distribution and administration, particularly in settings with limited cold-chain capacity or health workforce resources. This narrative review synthesises preclinical and clinical MAP vaccine research alongside literature on product development, manufacturing, regulation, implementation, acceptability, and equitable access, and reports encouraging early-phase tolerability and immunogenicity findings for influenza, Japanese encephalitis, measles–rubella, and SARS-CoV-2 MAP vaccines. Notable advantages include improved thermostability, antigen dose sparing, simplified application, the possibility of self- or layperson administration, reduced reliance on trained vaccinators, and suitability for outreach and low-resource settings. Advancing MAP technology requires selection of target vaccines, development of stable, antigen-specific formulations, confirmation of dose delivery, completion of phased clinical trials and regulatory assessments, establishment of scalable, quality-controlled manufacturing systems, and integration into immunization programmes. Challenges involve antigen compatibility, dose consistency, formulation stability, manufacturing scale-up, regulatory requirements, uncertain costs and commercial incentives, public acceptance, and equitable access. Following licensure, Phase IV surveillance and effectiveness studies will be needed to evaluate real-world safety and performance. Investment across research, manufacturing, regulation, and delivery is essential to position MAPs as complementary tools to conventional vaccines, thus broadening the speed, reach, and flexibility of pandemic immunization responses.