Topical antiviral compositions, delivery systems, and methods of using the same

1. A delivery system comprising a composition, the composition comprising a nitric oxide (NO)-releasing active pharmaceutical ingredient,

wherein the NO-releasing active pharmaceutical ingredient is a diazeniumdiolated co-condensed silica particle and is present in the composition in an amount of 0.01% to 30% by weight of the composition,

wherein the composition has a Cmax of greater than 160 pmol of NO/mg, as measured by in vitro release testing, and

wherein the composition has a pH of about 5 to about 8.

2. The delivery system of claim 1 , wherein the composition stores and/or releases nitric oxide in an amount of about 0.05% to about 10% by weight of the composition.

3. The delivery system of claim 1 , wherein the delivery system is configured for delivery to a body cavity of a subject.

4. The delivery system of claim 1 , wherein the delivery system is configured to contact the composition to a mucous membrane of the subject.

5. The delivery system of claim 1 , wherein the delivery system is configured to contact the composition to a nostril, mouth, tongue, and/or pharynx of the subject.

6. The delivery system of claim 1 , wherein the composition further comprises water.

7. The delivery system of claim 1 , wherein the delivery system administers nitric oxide in an amount sufficient to induce apoptosis in virally infected cells.

8. The delivery system of claim 1 , wherein the delivery system administers nitric oxide in an amount sufficient to reduce or eliminate viral replication with less than about 50% host cell cytotoxicity.

9. The delivery system of claim 1 , wherein the diazeniumdiolated co-condensed silica particle comprises a co-condensed silica network comprising diazeniumdiolated aminoethylaminopropyl trimethoxy silane (AEAP3) and tetra methyl orthosilicate (TMOS).

10. The delivery system of claim 1 , wherein the diazeniumdiolated co-condensed silica particle comprises a co-condensed silica network comprising diazeniumdiolated methylaminopropyl trimethoxysilane (MAP3) and tetra methyl orthosilicate (TMOS).

11. The delivery system of claim 1 , wherein the diazeniumdiolated co-condensed silica particle comprises a co-condensed silica network comprising diazeniumdiolated methylaminopropyl trimethoxysilane (MAP3) and tetraethyl orthosilicate (TEOS).

12. A method of administering nitric oxide to a subject to treat and/or prevent a viral infection in a subject, the method comprising:

administering a composition comprising a nitric oxide (NO)-releasing active pharmaceutical ingredient,

wherein the NO-releasing active pharmaceutical ingredient is a diazeniumdiolated co-condensed silica particle and is present in the composition in an amount of 0.01% to 30% by weight of the composition,

wherein the composition has a C max of greater than 160 pmol of NO/mg, as measured by in vitro release testing, and

wherein the composition has a pH of about 5 to about 8.

13. The method of claim 12 , wherein the composition stores and/or releases nitric oxide in an amount of about 0.05% to about 10% by weight of the composition.

14. The method of claim 12 , wherein the administering comprises administering the composition to a body cavity of a subject.

15. The method of claim 12 , wherein the administering comprises administering the composition to a mucous membrane of the subject.

16. The method of claim 12 , wherein the administering comprises administering the composition to a nostril, mouth, tongue, and/or pharynx of the subject.

17. The method of claim 12 , wherein the administering comprises administering nitric oxide in an amount sufficient to induce apoptosis in virally infected cells in the subject.

18. The method of claim 12 , wherein the administering comprises administering nitric oxide in an amount sufficient to reduce or eliminate viral replication with less than about 50% host cell cytotoxicity.

19. The method of claim 12 , wherein the composition further comprises water.

20. The method of claim 12 , wherein the diazeniumdiolated co-condensed silica particle comprises a co-condensed silica network comprising diazeniumdiolated methylaminopropyl trimethoxysilane (MAP3) and tetra methyl orthosilicate (TMOS).