Human cytomegalovirus immunogenic composition

1. A subunit vaccine comprising an immunogenic composition consisting of:

a purified protein HCMV gB antigen;

a purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen; and

a Th1-inducing adjuvant, wherein said Th1-inducing adjuvant comprises a TLR4 agonist or a linear or branched polyacrylic acid polymer salt with a weight average molecular weight Mw in the range of 350 to 650 kDa.

2. The subunit vaccine according to claim 1 , wherein said Th1-inducing adjuvant induces in mice a lower IgG1:IgG2a,c ratio, and/or a higher INF-y level, and/or a lower IL-5 level than MF59 in a composition comprising the same purified protein HCMV gB antigen and the same purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen.

3. The subunit vaccine according to claim 1 , wherein said purified protein HCMV gB antigen comprises one or several mutations at the endoproteolytic cleavage site.

4. The subunit vaccine according to claim 1 , wherein said purified protein HCMV gB antigen is a full length gB polypeptide, a full length gB polypeptide lacking at least a portion of a transmembrane domain of the gB polypeptide, a full length gB polypeptide lacking at least 80% of the amino acid sequence of the transmembrane domain, a full length gB polypeptide lacking at least a portion of an intracellular domain of the gB polypeptide, a full length gB polypeptide lacking at least 80% of the amino acid sequence of the intracellular domain, or a full length gB polypeptide lacking at least 80% of the amino acid sequences of both the transmembrane domain and the intracellular domain.

5. The subunit vaccine according to claim 1 , wherein said purified protein HCMV gB antigen is gBdTm.

6. The subunit vaccine according to claim 1 , wherein in the said purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen, the gH antigen lacks at least a portion of a transmembrane domain of the full length gH.

7. The subunit vaccine according to claim 6 , wherein said gH antigen comprises an ectodomain of the full length gH encoded by UL75 gene.

8. The subunit vaccine according to claim 1 , wherein the purified protein HCMV gB and the purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex are the sole HCMV protein antigens.

9. The subunit vaccine according to claim 1 , wherein said vaccine increases neutralizing antibody levels and/or persistence.

10. The subunit vaccine according to claim 6 , wherein in the purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen, the gH antigen lacks at least 80% of the amino acid sequence corresponding to the transmembrane domain.

11. A subunit vaccine comprising an immunogenic composition consisting of:

a purified protein HCMV gB antigen;

a purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen; and

a TLR4 agonist.

12. The subunit vaccine according to claim 11 , wherein said TLR4 agonist is in combination with a delivery system.

13. The subunit vaccine according to claim 12 , wherein the delivery system is selected from the group consisting of aqueous nanosuspension, calcium phosphate, liposomes, virosomes, ISCOMs, micro- and nanoparticles, and emulsions.

14. The subunit vaccine according to claim 11 , wherein said TLR-4 agonist is selected from the group consisting of: a lipopolysaccharide, a monophosphoryl lipid A (MPL), a 3-de-O-acylated monophosphoryl lipid A (3D-MPL), a glucopyranosyl lipid adjuvant (GLA), a second-generation Lipid Adjuvant (SLA), a phospholipid dimer connected by a noncarbohydrate backbone and an aminoalkyl glucosaminide phosphate, or a derivative thereof.

15. The subunit vaccine according to claim 12 , wherein TLR-4 agonist in combination with a delivery system is AS01 or AS02.

16. The subunit vaccine according to claim 11 , wherein said TLR-4 agonist is GLA (CAS Number 1246298-63-4) TLR-4 agonist.

17. A subunit vaccine comprising an immunogenic composition consisting of:

a purified protein HCMV gB antigen;

a purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen; and

a linear or branched polyacrylic acid polymer salt with a weight average molecular weight Mw in the range of 350 to 650 kDa.

18. The subunit vaccine according to claim 17 , wherein said linear or branched polyacrylic acid polymer salt is PAA225000.

19. A method of preventing a disease associated with HCMV infection in a patient in need thereof, comprising the administration of an immunologically effective amount of a subunit vaccine comprising an immunogenic composition consisting of:

a purified protein HCMV gB antigen;

a purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen; and

a TLR4 agonist or a linear or branched polyacrylic acid polymer salt with a weight average molecular weight Mw in the range of 350 to 650 kDa, thereby preventing the disease associated with HMCV infection in the patient.

20. A method of producing a subunit vaccine comprising an immunogenic composition, the method comprising:

providing purified protein antigens consisting of a purified protein HCMV gB antigen and a purified protein HCMV gH/gL/UL128/UL130/UL131 pentameric complex antigen; and

combining the purified protein antigens with a TLR4 agonist, to thereby produce an immunogenic composition.