Thermostable vacuum foam dried Newcastle disease vaccine: Process optimization and pilot-scale study

Area of Science:

• Veterinary Virology
• Vaccine Technology
• Bioprocessing Engineering

Background:

• Newcastle Disease Virus (NDV) is a significant pathogen in poultry, necessitating stable vaccine formulations for effective disease control.
• Traditional vaccine preservation methods often require cold chain logistics, posing challenges for widespread application, especially in resource-limited settings.

Purpose of the Study:

• To optimize the vacuum foam drying (VFD) process for enhancing the thermostability and long-term shelf life of Newcastle Disease Virus (NDV) vaccine.
• To evaluate the scalability of the optimized VFD process from laboratory to pilot scale for potential industrialization.

Main Methods:

• Optimization of key VFD parameters including virus-to-formulation ratio (1:1 or 3:2), filling volume (13-17% vial capacity), shelf temperature (25°C), and drying time (minimum 44 hours).
• Laboratory-scale validation of optimized VFD conditions, assessing virus titer loss and residual moisture content (RMC).
• Thermostability testing through 97-day ambient temperature transportation across China.
• Pilot-scale VFD process testing to assess scalability and vaccine quality.

Main Results:

• Laboratory-scale optimized VFD produced NDV vaccine with ≤1.0 log10 virus titer loss and RMC <3%.
• NDV-VFD vaccine samples demonstrated thermostability, with no significant titer loss after 97 days of ambient temperature transport.
• Pilot-scale production achieved RMC <3%, but with a slight increase in virus titer loss (approx. 1.1 log10), indicating a need for further pilot-scale optimization.

Conclusions:

• The optimized vacuum foam drying process significantly improves the thermostability and shelf life of Newcastle Disease Virus vaccine.
• The study demonstrates the feasibility of producing a thermostable NDV vaccine through VFD, with successful laboratory-scale validation and promising pilot-scale results.
• Further optimization of the VFD process at pilot scale is recommended to achieve target virus titer loss for successful industrialization.