Enhanced Stability of Inactivated Influenza Vaccine Encapsulated in Dissolving Microneedle Patches

• Authors: Leonard Y. Chu, Emory University; Ling Ye, Emory University; Ke Dong, Emory University; Richard Compans, Emory University; Chinglai Yang, Emory University; Mark Prausnitz, Emory University
• Journal Title: Pharmaceutical Research
• Volume: Volume 33, Number 4
• Publisher: American Association of Pharmaceutical Scientists | 2016-04-01, Pages 868-878
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1007/s11095-015-1833-9
• Subjects: Biology, Virology; Health Sciences, Immunology; Engineering, Biomedical
• Keywords: Science & Technology; Physical Sciences; Life Sciences & Biomedicine; Chemistry, Multidisciplinary; Pharmacology & Pharmacy; Chemistry; influenza vaccine immunogenicity; microneedle patch; thermostability; vaccine stability; IMMUNE-RESPONSES; DELIVERY; VIRUS; DRUG; STABILIZATION; SKIN; PROTEINS; STATE; IMMUNOGENICITY; TEMPERATURES

Abstract

Purpose: This study tested the hypothesis that encapsulation of influenza vaccine in microneedle patches increases vaccine stability during storage at elevated temperature. Methods: Whole inactivated influenza virus vaccine (A/Puerto Rico/8/34) was formulated into dissolving microneedle patches and vaccine stability was evaluated by in vitro and in vivo assays of antigenicity and immunogenicity after storage for up to 3 months at 4, 25, 37 and 45°C. Results: While liquid vaccine completely lost potency as determined by hemagglutination (HA) activity within 1-2 weeks outside of refrigeration, vaccine in microneedle patches lost 40-50% HA activity during or shortly after fabrication, but then had no significant additional loss of activity over 3 months of storage, independent of temperature. This level of stability required reduced humidity by packaging with desiccant, but was not affected by presence of oxygen. This finding was consistent with additional stability assays, including antigenicity of the vaccine measured by ELISA, virus particle morphological structure captured by transmission electron microscopy and protective immune responses by immunization of mice in vivo. Conclusions: These data show that inactivated influenza vaccine encapsulated in dissolving microneedle patches has enhanced stability during extended storage at elevated temperatures.