Microneedles Based Thermally Stable Ad-5 Viral Vector for Vaccine Delivery

Area of Science:

• Biotechnology
• Vaccinology
• Materials Science

Background:

• Adenoviral (Ad) vectored vaccines are crucial for veterinary and human health but face deployment challenges due to cold chain dependence and needle-based delivery.
• Existing Ad vaccines require strict temperature control and invasive injections, limiting their accessibility and global reach.

Purpose of the Study:

• To develop a novel technology, Stabilized Prophylactic Adenovirus Nanostructure Delivery via Microneedles (SPAND-MN), for room-temperature storage and transdermal administration of Ad vectored vaccines.
• To demonstrate the efficacy, stability, and safety of the SPAND-MN platform for delivering Ad5 vaccines expressing various antigens.

Main Methods:

• The SPAND-MN platform was developed to encapsulate replication-defective Adenovirus serotype 5 (Ad5) vaccine vectors.
• Vaccine formulations were subjected to accelerated (60°C) and long-term (45°C for 1 month) thermal stress.
• In vitro and in vivo studies assessed transduction efficiency, dose delivery, biocompatibility, safety, and immunogenicity compared to traditional refrigerated vaccines.

Main Results:

• The SPAND-MN formulation successfully delivered Ad5 vectors expressing GFP, Luc, and FMD antigens.
• SPAND-MN preserved vaccine transduction capacity after thermal challenges, demonstrating room-temperature stability.
• In vivo studies confirmed effective delivery, biocompatibility, safety (no cytotoxicity or organ toxicity), and maintained immunogenicity equivalent to refrigerated vaccines.

Conclusions:

• The SPAND-MN platform offers a promising solution for cold-chain free, painless, and easy transdermal delivery of Ad5 vaccines.
• This microneedle patch technology has the potential to significantly enhance the global deployment and accessibility of adenoviral vaccines.