Abstract
Adjuvants play an important role to enhance the efficacy of vaccines and are often required to direct immune responses toward specific long-term protection. Several vaccination trials have described promising results with the combination of recombinant adenoviruses and water-in-oil-in-water (W/O/W) adjuvants. Specifically, the antibody response elicited by vaccines based on canine adenovirus type 2 (CAV2) vectors steadily increases after being formulated in a W/O/W emulsion. Thus, the production process directly impacts its physical properties, which are crucial to obtain stable, safe, and efficient vaccine emulsions. This article describes a lab-scale process for the formulation of O-206, a W/O/W adjuvant, in a total volume of 1 mL and 10 mL, that is compatible with safety requirements of live vaccines based on recombinant adenovirus. Moreover, this article provides reliable and simple quality control analyses of the W/O/W vaccine emulsion formulated with recombinant adenoviruses.