HYDROPHILIC FILTRATION DURING MANUFACTURE OF VACCINE ADJUVANTS
An improved method for the manufacture of an oil-in-water emulsion involves three procedures: (i) preparation of a preliminary emulsion; (ii) micro fluidization of the preliminary emulsion to reduce its droplet size; and (iii) filtration of the microfluidized emulsion through a hydrophilic membrane. The emulsions are useful as vaccine adjuvants.
1 - 3 . (canceled)
4 . A method for the manufacture of a squalene-containing oil-in-water emulsion, comprising the steps of:
(i) forming a first emulsion having a first average oil droplet size;
(ii) microfluidizing the first emulsion to form a second emulsion having a second average oil droplet size which is less than the first average oil droplet size;
(iii) prefiltering the second emulsion through a first hydrophilic polyethersulfone membrane; and
(iv) filtering the second emulsion using a second hydrophilic polyethersulfone membrane.
5 . The method according to claim 4 , wherein the first average oil droplet size is 5000 nm or less.
6 . The method according to claim 4 or claim 5 , wherein the number of oil droplets having a size of >1.2 μm in the first emulsion is 5×10 11 /ml or less.
7 . The method according to claim 6 , wherein the second average oil droplet size is 500 nm or less.
8 . The method according to claim 7 , wherein the number of oil droplets having a size of >1.2 μm in the second emulsion is 5×10 10 /ml or less.
9 . A method for manufacture of a squalene-containing oil-in-water emulsion, comprising the steps of:
(i) forming a squalene-containing emulsion having an average oil droplet size of 500 nm or less;
(ii) filtering the squalene-containing emulsion using a hydrophilic polyethersulfone filter which has a first membrane layer with larger pores and a second membrane layer with smaller pores.
10 . The method according to claims 4 or 9 , wherein the average oil droplet size after filtration is less than 220 nm.
11 . The method according to claims 4 or 9 , wherein the number of oil droplets having a size of >1.2 μm after filtration is 5×10 8 /ml or less.
12 .- 14 . (canceled)
15 . The method according to claims 4 or 9 , wherein the filtration membrane is asymmetric and/or porous.
16 . The method according to claims 4 or 9 , wherein the filtration membrane, and optionally the prefiltration membrane, comprises a polymeric support material.
17 . The method according to claims 4 or 9 , wherein (i) the first membrane has a pore size ≥0.3 μm, and/or (ii) the second membrane has a pore size <0.3 μm.
18 . A method for preparing a vaccine composition, comprising preparing an emulsion according to claims 4 or 9 , preparing an emulsion adjuvant comprising the emulsion, and combining the emulsion adjuvant with an antigen.
19 . A method for preparing a vaccine kit comprising preparing an emulsion according to claims 4 or 9 , preparing an emulsion adjuvant comprising the emulsion, and packaging the emulsion adjuvant into a kit as a kit component together with an antigen component.
20 . The method of claim 19 , wherein the kit components are in separate vials.
21 . The method of claim 20 , wherein the vials are made from borosilicate glass.
22 . The method of claim 18 , wherein the emulsion adjuvant is a bulk adjuvant and the method comprises extracting unit doses from the bulk adjuvant for packaging as kit components.
23 . The method of claim 18 , wherein the antigen is an influenza virus antigen.
24 . The method of claim 23 , 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 3.75 μg, about 1.9 μg, or about 1.5 μg of hemagglutinin per influenza virus strain.
25 . The method of claim 23 , wherein the combination of the emulsion and the antigen forms a vaccine composition and wherein the vaccine composition includes a thiomersal or 2-phenoxyethanol preservative.
26 . A method for the manufacture of a squalene-containing oil-in-water emulsion, comprising the steps of:
(i) forming a first emulsion having a first average oil droplet size;
(ii) microfluidizing the first emulsion to form a second emulsion having a second average oil droplet size which is less than the first average oil droplet size; and
(iii) filtering the second emulsion through a hydrophilic double-layer filter, wherein the double-layer filter comprises a first hydrophilic polyethersulfone membrane layer with larger pores and a second hydrophilic polyethersulfone membrane layer with smaller pores.
27 . (canceled)
28 . The method of claim 4 , wherein the prefiltration and filtration steps are carried out using a double-layer filter.
29 . The method according to claims 4 or 9 , wherein the prefiltration membrane is asymmetric and/or porous.
30 . The method of claim 9 , wherein the filtration is carried out using a double-layer filter.