Circulation of components during microfluidization and/or homogenization of emulsions
An improved method for the manufacture of an oil-in-water emulsion involves circulation of emulsion components between a first container and a second container via a homogenizer and/or via a microfluidization device. Usefully, all of the emulsion components from the first container are emptied before being returned.
1. A method for preparing a vaccine kit comprising:
1) preparing an emulsion by a method comprising the step of:
(a) forming a first emulsion having a first average oil droplet size; and
(b) microfluidizing the first emulsion having a first average oil droplet size to form a second emulsion having a second average oil droplet size which is less than the first average oil droplet size, wherein the second emulsion is formed by (a) at least one type I circulation of transferring the second emulsion components between a first container and a microfluidizer and (b) at least one type II circulation of transferring the second emulsion components from a first emulsion container, through a first microfluidization device to a second emulsion container, and then again through the same microfluidization device; and
2) packaging the emulsion into a kit as a kit component together with an antigen component.
2. The method of claim 1 , wherein the kit components are in separate vials.
3. The method of claim 2 , wherein the vials are made from borosilicate glass.
4. The method of claim 1 , wherein the adjuvant is a bulk adjuvant and the method comprises extracting unit doses from the bulk adjuvant for packaging as kit components.
5. The method of claim 1 , wherein the antigen is an influenza virus antigen.
6. The method of claim 5 , wherein the combination of the emulsion and the antigen forms a vaccine composition and wherein the vaccine composition includes about 15 μg, about 10 μg, about 7.5 μg, about 5 μg, about 3.8 μg, about 1.9 μg, about 1.5 μg of hemagglutinin per influenza virus strain.
7. The method of claim 5 , wherein the combination of the emulsion and the antigen forms a vaccine composition and wherein the vaccine composition includes a thimerosal or 2-phenoxyethanol preservative.