Sterile filtration of a parenteral emulsion.

The Syntex adjuvant formulation (SAF) containing [thr1]-muramyldipeptide in an oil-in-water emulsion has proven to be an effective adjuvant eliciting both cell-mediated and humoral immune response. As a parenteral emulsion, sterility of the final product was a concern, and various methods of achieving sterility were considered. For emulsions, most conventional sterilization methods are not viable, requiring the more cumbersome technique of sterilizing individual components and assembling/manufacturing under sterile conditions.