Project Summary/Abstract The World Health Organization estimates that each year influenza causes serious illness in 3 to 5 million people and up to 650,000 deaths globally. While seasonal vaccines to prevent influenza infection are available, frequent mutations in the virus require manufacturers to guess which strains will circulate each season and reformulate the vaccine annually. As a result, the public health benefit of seasonal vaccines is hampered by poor efficacy (estimated at 36% for the 2017-18 season). This challenge highlights the critical need to improve influenza vaccines to boost humoral responses (onset, magnitude, and breadth) and generate additional cellular immunity. Our technology focuses on engineering the sustained release of seasonal influenza vaccine antigen to mimic natural infection kinetics over 2 weeks, resulting in greater diversity of anti-influenza antibodies and improved T cell responses. This is accomplished using silk fibroin biomaterial in a microneedle array format that can be easily administered to the skin. After a brief 5 minute wear time, the silk microneedle tips are released from the patch and implanted within the dermis. These silk tips are engineered to stabilize vaccine antigens at body temperature while slowly releasing the antigen payload over 2 weeks. In animal studies comparing conventional injection to our sustained release approach, we demonstrated a 4-fold increase in protective T-cells, a 5-fold increase in antibody titers, and significantly higher survival following lethal challenge. Patch administration was also well tolerated in dermatological models (hairless guinea pigs and yorkshire swine). Building upon these preclinical proof-of-concept results, the objective of our proposed work is to prepare for clinical translation and commercialization of this technology through implementation of a Quality Management System, optimization and finalization of device design, establishment of GMP manufacturing and other CMC-related activities, and regulatory engagement to ensure compliance with FDA requirements. Having completed these aims, Vaxess will be positioned to file an IND and begin a Phase 1 clinical study on a path to commercialization of our microarray patch for broadly protective seasonal influenza vaccination, MIMIX-Flu.