Compositions and methods for inhibiting expression of Huntingtin gene
The invention relates to a double-stranded ribonucleic acid (dsRNA) for inhibiting the expression of the Huntingtin gene (HD gene), comprising an antisense strand having a nucleotide sequence which is less than 25 nucleotides in length and which is substantially complementary to at least a part of the HD gene. The invention also relates to a pharmaceutical composition comprising the dsRNA together with a pharmaceutically acceptable carrier; methods for treating diseases caused by the expression of the HD gene, or a mutant form thereof, using the pharmaceutical composition; and methods for inhibiting the expression of the huntingtin gene in a cell.
1. A double-stranded ribonucleic acid (dsRNA) for inhibiting the expression of a human Huntingtin (HD) gene, wherein said dsRNA is between 15 and 30 base pairs in length and comprises a sense strand comprising a first sequence and an antisense strand comprising a second sequence, and wherein the nucleotide sequence of the second sequence comprises at least 15, 16, 17, 18, 19, 20, or 21 contiguous nucleotides of SEQ ID NO: 793.
2. The dsRNA of claim 1 , wherein said dsRNA comprises at least one modified nucleotide.
3. The dsRNA of claim 2 , wherein said modified nucleotide is chosen from the group of: a 2′-O-methyl modified nucleotide, a nucleotide comprising a 5′ phosphorothioate group, and a terminal nucleotide linked to a cholesteryl derivative or dodecanoic acid bisdecylamide group.
4. The dsRNA of claim 2 , wherein said modified nucleotide is chosen from the group of: a 2′-deoxy-2′-fluoro modified nucleotide, a 2′-deoxy-modified nucleotide, a locked nucleotide, an abasic nucleotide, 2′-amino-modified nucleotide, 2′-alkyl-modified nucleotide, morpholino nucleotide, a phosphoramidate, and a non-natural base comprising nucleotide.
5. A pharmaceutical composition for inhibiting the expression of the HD gene, comprising the dsRNA of claim 1 and a pharmaceutically acceptable carrier.
6. A method for inhibiting expression of Huntingtin gene in a cell, the method comprising:
(a) introducing into the cell a double-stranded ribonucleic acid (dsRNA) of claim 1 ; and
(b) maintaining the cell produced in step (a) for a time sufficient to obtain degradation of the mRNA transcript of the Huntingtin gene, thereby inhibiting expression of the Huntingtin gene in the cell.
7. A method of treating or managing Huntington disease comprising administering to a patient in need of such treatment or management a therapeutically effective amount of the dsRNA of claim 1 .
8. A vector for inhibiting the expression of Huntingtin gene, said vector comprising a regulatory sequence operably linked to a nucleotide sequence that encodes at least one strand of the dsRNA of claim 1 .
9. A cell comprising the vector of claim 8 .
10. The method of claim 7 , wherein said dsRNA is administered to the brain of the patient.
11. The method of claim 7 , wherein said dsRNA is administered by intrastriatal infusion.
12. The method of claim 10 , wherein administering the dsRNA of claim 1 to the brain causes a decrease in HD mRNA in the striatum.
13. The method of claim 10 , wherein administering the dsRNA of claim 1 to the brain causes a decrease in HD mRNA in the cortex.
14. The dsRNA of claim 1 , wherein the dsRNA comprises a cholesterol moiety.
15. The dsRNA of claim 1 , wherein said dsRNA comprises at least one a 2′-O-methyl modified nucleotide and at least one nucleotide comprising a5′ phosphorothioate group.
16. The dsRNA of claim 1 , wherein the antisense strand comprises the nucleotide sequence of SEQ ID NO: 793.
17. The dsRNA of claim 1 , wherein said antisense strand comprises the nucleotide sequence of SEQ ID NO:793 and said antisense strand comprises a 2′-O-methyl modified nucleotide at location 4 and a phosphorothioate at location 21.
18. The dsRNA of claim 1 , wherein said sense strand comprises the nucleotide sequence of SEQ ID NO:792.
19. The dsRNA of claim 1 , wherein said sense strand comprises the nucleotide sequence of SEQ ID NO:792 and said sense strand comprises a 2′-O-methyl modified nucleotide at locations 2, 3, 5, 12, 13, 15, and 17 and a phosphorothioate at location 21.
20. The dsRNA of claim 1 , wherein said antisense strand comprises the nucleotide sequence of SEQ ID NO:793 and said antisense strand comprises a 2′-O-methyl modified nucleotide at location 4 and a phosphorothioate at location 21 and wherein said sense strand comprises the nucleotide sequence of SEQ ID NO:792 and said sense strand comprises a 2′-O-methyl modified nucleotide at locations 2, 3, 5, 12, 13, 15, and 17 and a phosphorothioate at location 21.
21. The dsRNA of claim 1 , wherein the antisense strand comprises at least one 5-bromo-2′-deoxyuridine at the 3′end.
22. The dsRNA of claim 1 , wherein said dsRNA, upon contact with a cell expressing said Huntingtin gene, inhibits expression of said Huntingtin gene by at least 20%.
23. The dsRNA of claim 1 , wherein the nucleotide sequence of the first sequence comprises at least 15, 16, 17, 18, 19, 20, or 21 contiguous nucleotides of SEQ ID NO:792.
24. The dsRNA of claim 1 , wherein the dsRNA reduces HD mRNA levels by more than 70% in HeLa cells compared to an siRNA duplex control.
25. The dsRNA of claim 1 , wherein the antisense strand consists of SEQ ID NO: 793.
26. The dsRNA of claim 1 , wherein the sense strand consists of SEQ ID NO:792.