RNAi inhibition of alpha-ENaC expression

1. A composition comprising an iRNA agent comprising a sense strand and an antisense strand, wherein:

a. the sense strand comprises at least 15 contiguous nucleotides from the sense strand of ND8453 (SEQ ID NO: 1425), and the antisense strand comprises at least 15 contiguous nucleotides from the antisense strand of ND8453 (SEQ ID NO: 1426); or

b. the sense strand comprises at least 15 contiguous nucleotides from the sense strand of ND8489 (SEQ ID NO: 1497), and the antisense strand comprises at least 15 contiguous nucleotides from the antisense strand of ND8489 (SEQ ID NO: 1498); or

c. the sense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2 or 3 nucleotides from the sense strand of ND8456 (SEQ ID NO: 1431), and the antisense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2 or 3 nucleotides from the antisense strand of ND8456 (SEQ ID NO: 1432).

2. The composition of claim 1 , wherein the antisense strand is 30 or fewer nucleotides in length, and wherein the sense strand and the antisense strand form a duplex region 15 to 30 nucleotide pairs in length.

3. The composition of claim 1 , wherein the antisense strand and the sense strand are each 19 to 23 nucleotides in length.

4. The composition of claim 1 , wherein the iRNA agent comprises a modification that causes the iRNA agent to have increased stability in a biological sample.

5. The composition of claim 1 , wherein the iRNA agent comprises a phosphorothioate or a 2′-modified nucleotide.

6. The composition of claim 1 , wherein the iRNA agent comprises:

at least one 5′-uridine-adenine-3′ (5′-ua-3′) dinucleotide, wherein the uridine is a 2′-modified nucleotide; at least one 5′-uridine-guanine-3′ (5′-ug-3′) dinucleotide, wherein the 5′-uridine is a 2′-modified nucleotide; at least one 5′-cytidine-adenine-3′ (5′-ca-3′) dinucleotide, wherein the 5′-cytidine is a 2′-modified nucleotide; or at least one 5′-uridine-uridine-3′ (5′-uu-3′) dinucleotide, wherein the 5′-uridine is a 2′-modified nucleotide.

7. The composition of claim 1 , wherein the iRNA agent comprises a 2′-modification selected from the group consisting of: 2′-deoxy, 2′-deoxy-2′-fluoro, 2′-O-methyl, 2′-O-methoxyethyl (2′-O-MOE), 2′-O-aminopropyl (2′-O-AP), 2′-O-dimethylaminoethyl (2′-O-DMAOE), dimethylaminopropyl (2′-O-DMAP), 2′-O-dimethylaminoethyloxyethyl (2′-O-DMAEOE), and 2′-O—N-methylacetamido (2′-O—N-methylacetamido (2′-O-NMA).

8. The composition of claim 1 , wherein the iRNA agent comprises a blunt end.

9. The composition of claim 1 , wherein the iRNA agent comprises a nucleotide overhang having 1 to 4 unpaired nucleotides.

10. The composition of claim 1 , wherein the iRNA agent comprises a nucleotide overhang at the 3′-end of the antisense strand of the iRNA agent.

11. The composition of claim 1 , wherein the iRNA agent is ND8453 (SEQ ID NOs. 1425 and 1426).

12. The composition of claim 1 , wherein the iRNA is ND8489 (SEQ ID NOs. 1497 and 1498).

13. The composition of claim 1 , wherein the iRNA is ND8456 (SEQ ID NOs. 1431 and SEQ ID NO: 1432).

14. The composition of claim 1 , wherein the iRNA agent is ligated to one or more diagnostic compound, reporter group, cross-linking agent, nuclease-resistance conferring moiety, natural or unusual nucleobase, lipophilic molecule, cholesterol, lipid, lectin, steroid, uvaol, hecigenin, diosgenin, terpene, triterpene, sarsasapogenin, Friedelin, epifriedelanol-derivatized lithocholic acid, vitamin, carbohydrate, dextran, pullulan, chitin, chitosan, synthetic carbohydrate, Oligo Lactate 15-mer, natural polymer, low- or medium-molecular weight polymer, inulin, cyclodextrin, hyaluronic acid, protein, protein-binding agent, integrin-targeting molecule, polycationic, peptide, polyamine, peptide mimic, and/or transferrin.

15. A method of treating a human subject having a pathological state mediated at least in part by alpha-ENaC expression, the method comprising the step of administering to the subject a therapeutically effective amount of a composition of claim 1 .

16. The method of claim 15 , wherein the pathological state is cystic fibrosis, primary ciliary dyskinesia, chronic bronchitis, chronic obstructive pulmonary disease (COPD), asthma, respiratory tract infections, lung carcinoma, Liddles syndrome, hypertension, renal insufficiency, and/or electrolyte imbalance.

17. A composition comprising an iRNA agent to alpha-ENaC, wherein the iRNA agent comprises a sense strand and an antisense strand, wherein the sense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2, or 3 nucleotides from the sense strand of an iRNA agent selected from the group consisting of ND8453 (SEQ ID NO: 1425), ND8489 (SEQ ID NO: 1497), and ND8456 (SEQ ID NO: 1431), and wherein the antisense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2, or 3 nucleotides from the antisense strand of an iRNA agent selected from the group consisting of ND8453 (SEQ ID NO: 1426); ND8489 (SEQ ID NO: 1498), and ND8456 (SEQ ID NO: 1432), the composition further comprising an epithelial receptor ligand.

18. The composition of claim 17 , wherein the epithelial receptor ligand is transferrin.

19. The composition of claim 17 , wherein the epithelial receptor ligand is folic acid.

20. A method of treating a human subject having a pathological state mediated at least in part by alpha-ENaC expression, the method comprising the step of administering to the subject a therapeutically effective amount of a composition of claim 17 .

21. The method of claim 20 , wherein the pathological state is cystic fibrosis, primary ciliary dyskinesia, chronic bronchitis, chronic obstructive pulmonary disease (COPD), asthma, respiratory tract infections, lung carcinoma, Liddles syndrome, hypertension, renal insufficiency, and/or electrolyte imbalance.

22. A method of treating a human subject having a pathological state mediated at least in part by alpha-ENaC expression, the method comprising the step of administering a therapeutically effective amount of a composition comprising an iRNA agent to alpha-ENaC, wherein the iRNA agent comprises a sense strand and an antisense strand, wherein the sense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2, or 3 nucleotides from the sense strand of an iRNA agent selected from the group consisting of ND8453 (SEQ ID NO: 1425), ND8489 (SEQ ID NO: 1497), and ND8456 (SEQ ID NO: 1431), and wherein the antisense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2, or 3 nucleotides from the antisense strand of an iRNA agent selected from the group consisting of ND8453 (SEQ ID NO: 1426); ND8489 (SEQ ID NO: 1498), and ND8456 (SEQ ID NO: 1432).

23. The method of claim 22 , wherein the composition is administered in an amount sufficient to reduce the level of alpha-ENaC expression in a cell or tissue of the subject.

24. The method of claim 23 , wherein the pathological state is cystic fibrosis, primary ciliary dyskinesia, chronic bronchitis, chronic obstructive pulmonary disease (COPD), asthma, respiratory tract infections, lung carcinoma, Liddles syndrome, hypertension, renal insufficiency, and/or electrolyte imbalance.

25. A composition comprising an iRNA agent comprising a sense strand and an antisense strand, wherein the sense strand comprises at least 15 contiguous nucleotides from the sense strand of ND8453 (SEQ ID NO: 1425), and the antisense strand comprises at least 15 contiguous nucleotides from the antisense strand of ND8453 (SEQ ID NO: 1426).

26. A composition comprising an iRNA agent comprising a sense strand and an antisense strand, wherein the sense strand comprises at least 15 contiguous nucleotides from the sense strand of ND8489 (SEQ ID NO: 1497), and the antisense strand comprises at least 15 contiguous nucleotides from the antisense strand of ND8489 (SEQ ID NO: 1498).

27. A composition comprising an iRNA agent comprising a sense strand and an antisense strand, wherein the sense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2 or 3 nucleotides from the sense strand of ND8456 (SEQ ID NO: 1431), and the antisense strand comprises at least 15 contiguous nucleotides differing by 0, 1, 2 or 3 nucleotides from the antisense strand of ND8456 (SEQ ID NO: 1432).