Rational design of a stable, freeze-dried virus-like particle-based vaccine formulation

Area of Science:

• Vaccine Development
• Biopharmaceutical Formulation
• Analytical Chemistry

Background:

• Virus-like particles (VLPs) are extensively researched as vaccine candidates for infectious diseases, chronic conditions, and addiction.
• A nicotine vaccine (NicQb) using RNA phage Qb VLPs shows efficacy in smoking cessation clinical trials.
• Commercialization requires stable formulations for prolonged storage, with lyophilization being a key method.

Purpose of the Study:

• To investigate the impact of pH and various excipients on NicQb stability.
• To develop stable lyophilized NicQb formulations for long-term storage.
• To establish asymmetrical flow field-flow fractionation (AF4) for VLP stability analysis.

Main Methods:

• Testing NicQb stability in liquid formulations under different pH conditions.
• Evaluating the effects of surfactants, polyols, sugars, and salts during freeze-thawing and freeze-drying.
• Assessing the stability of lyophilized NicQb formulations over six months at ambient temperature.
• Utilizing asymmetrical flow field-flow fractionation (AF4) to analyze VLP integrity.

Main Results:

• Lyophilized NicQb formulations demonstrated stability for over six months at ambient temperature.
• A combination of polysorbate 20 (surfactant) and trehalose (disaccharide) effectively prevented NicQb aggregation.
• The VLP shell integrity and nicotine binding capacity were preserved in the optimized formulation.
• AF4 proved to be a valuable tool for VLP stability assessment.

Conclusions:

• Stable, lyophilized NicQb vaccine formulations can be achieved for commercialization.
• Polysorbate 20 and trehalose are key excipients for stabilizing NicQb during lyophilization and storage.
• The developed formulation retains biological activity and VLP integrity, supporting its use in smoking cessation therapies.