CORONAVIRUS VACCINES COMPRISING A TLR9 AGONIST
The present disclosure relates to immunogenic compositions comprising a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen, and a toll-like receptor 9 (TLR9) agonist, such as an oligonucleotide comprising an unmethylated cytidine-phospho-guano sine (CpG) motif. The immunogenic compositions are suitable for stimulating an immune response against a SARS-CoV-2 in an individual in need thereof.
1 . An immunogenic composition for stimulating an immune response against a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), comprising a SARS-CoV-2 antigen and a toll-like receptor 9 (TLR9) agonist, wherein the SARS-CoV-2 antigen is an inactivated whole SARS-CoV-2, the TLR9 agonist is an oligonucleotide of from 10 to 35 nucleotides in length comprising an unmethylated cytidine-phospho-guanosine (CpG) motif, and the SARS-CoV-2 antigen and the oligonucleotide are present in the immunogenic composition in amounts effective to stimulate an immune response against the SARS-CoV-2 antigen in a mammalian subject.
2 . The composition of claim 1 , wherein the oligonucleotide comprises the sequence
(SEQ ID NO: 3)
5′-AACGTTCGAG-3′.
3 . The composition of claim 1 , wherein the oligonucleotide comprises the sequence of 5′-TGACTGTGAA CGTTCGAGAT GA-3′(SEQ ID NO:1).
4 . The composition of claim 1 , wherein the oligonucleotide comprises a modified nucleoside, optionally wherein the modified nucleoside is selected from the group consisting of 2′-deoxy-7-deazaguanosine, 2′-deoxy-6-thioguanosine, arabinoguanosine, 2′-deoxy-2′substituted-arabinoguanosine, and 2′-O-substituted-arabinoguanosine.
5 . The composition of claim 4 , wherein the oligonucleotide comprises the sequence 5′-TCG 1 AACG 1 TTCG 1 -3′ (SEQ ID NO:2) in which G 1 is 2′-deoxy-7-deazaguanosine, optionally wherein the oligonucleotide comprises the sequence 5′-TCG 1 AACG 1 TTCG 1 -X-G 1 CTTG 1 CAAG 1 CT-5′, and in which G 1 is 2′-deoxy-7-deazaguanosine and X is glycerol (5′-SEQ ID NO:2-3′-X-3′-SEQ ID NO:2-5′).
6 . The composition of claim 3 , wherein the oligonucleotide comprises at least one phosphorothioate linkage, or wherein all nucleotide linkages are phosphorothioate linkages.
7 . The composition of claim 6 , wherein the oligonucleotide is a single-stranded oligodeoxynucleotide.
8 . The composition of claim 7 , wherein a 0.5 ml dose of the immunogenic composition comprises from about 750 to about 3000 μg of the oligonucleotide, or wherein the immunogenic composition comprises about 750 μg, about 1000 μg, about 1500 μg, or about 3000 μg of the oligonucleotide.
9 . The composition of claim 8 , wherein the SARS-CoV-2 antigen is propagated in vitro in mammalian cells.
10 . The composition of claim 9 , wherein the SARS-CoV-2 is inactivated by treatment with one or both of formalin and ultraviolet light.
11 . The composition of claim 9 , wherein the SARS-CoV-2 is inactivated by treatment with beta-propriolactone.
12 . The composition of claim 11 , wherein the SARS-CoV-2 comprises a combination of at least two different viral strains, or two different viral clades or lineages.
13 . The composition of claim 11 , wherein a 0.5 ml dose of the immunogenic composition comprises from about 0.025 to about 25 μg of the of the SARS-CoV-2 spike (S) protein, or from about 0.25 to about 25 μg of the of the S protein.
14 . The composition of any one of claims 1 - 13 , further comprising an aluminum salt adjuvant.
15 . The composition of claim 14 , wherein the aluminum salt adjuvant comprises one or more of the group consisting of amorphous aluminum hydroxyphosphate sulfate, aluminum hydroxide, aluminum phosphate, and potassium aluminum sulfate
16 . The composition of claim 14 , wherein the aluminum salt adjuvant comprises aluminum hydroxide.
17 . The composition of claim 15 , wherein a 0.5 ml dose of the immunogenic composition comprises from about 0.05 to about 0.50 mg Al 3+ , or about 0.075 to about 0.175 mg Al 3+ .
18 . The composition of claim 17 , wherein the mammalian subject is a human subject.
19 . A kit comprising:
i) the immunogenic composition of claim 14 , and
ii) instructions for administration of the composition to stimulate an immune response against the SARS-CoV-2 antigen in the mammalian subject.
20 . The kit of claim 19 , further comprising iii) a syringe and needle for intramuscular injection of the immunogenic composition.
21 . A method for stimulating an immune response against a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a mammalian subject, comprising administering the immunogenic composition of claim 14 to a mammalian subject so as to stimulate an immune response against the SARS-CoV-2 antigen in the mammalian subject.
22 . The method of claim 21 , wherein the mammalian subject is a human subject and/or the immunogenic composition is administered by intramuscular injection.
23 . Use of the immunogenic composition of claim 14 for stimulating an immune response against a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a mammalian subject, the method comprising administering to the subject an effective amount of the immunogenic composition.
24 . Use of the immunogenic composition of claim 14 for protecting a mammalian subject from infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the method comprising administering to the subject an effective amount of the immunogenic composition.
25 . Use of the immunogenic composition of claim 14 for preventing a mammalian subject from contracting COVID-19 disease, the method comprising administering to the subject an effective amount of the immunogenic composition.
26 . The use of any one of claims 23 - 25 , wherein the mammalian subject is a human subject and/or the immunogenic composition is administered by intramuscular injection.