ExPEC glycoconjugate vaccine formulations

1. A composition comprising:

a. at least one E. coli O-antigen polysaccharide, wherein the at least one E. coli O-antigen polysaccharide is covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein;

b. 3% to 8% (w/v) sorbitol;

c. 5 to 15 mM methionine;

d. 5 to 20 mM phosphate buffer comprising potassium phosphate and sodium phosphate at a pH of 6.5 to 7.5;

e. 0.01% to 0.2% (w/v) surfactant; and

f. water.

2. The composition of claim 1 , wherein the concentration of sorbitol is 5% (w/v).

3. The composition of claim 1 , wherein the concentration of methionine is 10 mM.

4. The composition of claim 1 , wherein the concentration of the phosphate buffer is 10 mM, and the pH of the phosphate buffer is 7.0.

5. The composition of claim 1 , wherein the surfactant is a non-ionic surfactant.

6. The composition of claim 5 , wherein the surfactant is polysorbate 80 (PS80).

7. The composition of claim 1 , wherein the surfactant is selected from the group consisting of poloxamer 188, polysorbate 20 (PS20), and polysorbate 80 (PS80).

8. The composition of claim 1 , which is stable for at least 6 months when stored at a temperature of 2-8° C.

9. The composition of claim 1 , comprising two or more E. coli O-antigen polysaccharides, wherein the concentration of each of the E. coli O-antigen polysaccharides is independently about 1 to 200 μ/mL.

10. The composition of claim 1 , which is stable for at least 6 months when stored at a temperature of −18° C. to −80° C.

11. The composition of claim 1 , being an immunogenic composition.

12. The composition of claim 1 , in a container made of glass, polycarbonate, or polyethylene terephthalate.

13. A composition comprising:

a. at least one E. coli O-antigen polysaccharide, wherein the at least one E. coli O-antigen polysaccharide is covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein;

b. 5% (w/v) sorbitol;

c. 10 mM methionine;

d. 10 mM phosphate buffer comprising KH 2 PO 2 and Na 2 HPO 4 at a pH of 7.0;

e. 0.02% (w/v) polysorbate 80 (PS80); and

f. water.

14. The composition of claim 13 , being an immunogenic composition.

15. A method of preparing a composition according to claim 1 , the method comprising mixing:

a. at least one E. coli O-antigen polysaccharide, wherein the at least one E. coli O-antigen polysaccharide is covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein;

b. 3% to 8% (w/v) sorbitol;

c. 5 to 15 mM methionine;

d. 5 to 20 mM phosphate buffer comprising potassium phosphate and sodium phosphate at a pH of 6.5 to 7.5;

e. 0.01% to 0.2% (w/v) surfactant; and

f. water,

to thereby prepare the composition.

16. The method according to claim 15 , further comprising storing the composition at a temperature of 2-8° C. for at least 6 months.

17. The method according to claim 15 , further comprising storing the composition at a temperature of −18° C. to −80° C. for at least 6 months.

18. A method for stably maintaining an E. coli O-antigen polysaccharide in a liquid composition, comprising preparing the liquid composition and storing the liquid composition at a temperature of 2-8° C., the liquid composition comprising:

a. 1 to 200 μg/mL of the E. coli O-antigen polysaccharide covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein;

b. 3% to 8% (w/v) sorbitol;

c. 5 to 15 mM methionine;

d. 5 to 20 mM phosphate buffer comprising potassium phosphate and sodium phosphate at a pH of 6.5 to 7.5;

e. 0.01% to 0.2% (w/v) surfactant, and f. water.

19. The method of claim 18 , wherein the liquid composition is stored at the temperature of 2-8° C. for at least 6 months.

20. The method of claim 18 , wherein the liquid composition comprises:

a. 1 to 200 μg/mL of the E. coli O-antigen polysaccharide covalently bound to the EPA carrier protein, optionally one or more other E. coli O-antigen polysaccharides covalently bound to an EPA carrier protein;

b. 5% (w/v) sorbitol;

c. 10 mM methionine;

d. 10 mM phosphate buffer comprising KH 2 PO 2 and Na 2 HPO 4 at a pH of 7.0;

e. 0.02% (w/v) polysorbate 80 (PS80); and

f. water.

21. The composition of claim 1 , in a syringe.

22. The composition of claim 1 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O25B antigen polysaccharide.

23. The composition of claim 1 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O1A antigen polysaccharide.

24. The composition of claim 1 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O2 antigen polysaccharide.

25. The composition of claim 1 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O6A antigen polysaccharide.

26. The composition of claim 1 , comprising an E. coli O25B antigen polysaccharide, an E. coli O1A antigen polysaccharide, an E. coli O2 antigen polysaccharide, and an E. coli O6A antigen polysaccharide, wherein each O-antigen polysaccharide is independently covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein.

27. The composition of claim 1 , comprising an E. coli O25B antigen polysaccharide and 1-20 additional E. coli O-antigen polysaccharides, wherein each O-antigen polysaccharide is independently covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein.

28. The composition of claim 13 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O25B antigen polysaccharide.

29. The composition of claim 13 , comprising an E. coli O25B antigen polysaccharide, an E. coli O1A antigen polysaccharide, an E. coli O2 antigen polysaccharide, and an E. coli O6A antigen polysaccharide, wherein each O-antigen polysaccharide is independently covalently bound to an exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein.

30. The method of claim 18 , wherein the at least one E. coli O-antigen polysaccharide comprises an E. coli O25B antigen polysaccharide.