US 8,138,161 B2 · Modified small interfering RNA molecules and methods of use

Abstract

The present invention provides double-stranded RNA molecules that mediate RNA interference in target cells, preferably hepatic cells. The invention also provides double-stranded RNA (dsRNA) molecules that are modified to be resistant to nuclease degradation, which inactivates a virus, and more specifically, hepatitis C virus (HCV). The invention also provides a method of using these modified RNA molecules to inactivate virus in mammalian cells and a method of making modified small interfering RNAs (siRNAs) using human Dicer. The invention provides modified RNA molecules that are modified to include a dsRNA or siRNA wherein one or more of the pyrimidines in the RNA molecule are modified to include 2′-Fluorine. The invention also provides dsRNA or siRNA in which all pyrimidines are modified to include a 2′-Fluorine. The invention provides that the 2′-Fluorine dsRNA or siRNA molecule is further modified to include a two base deoxynucleotide “TT” sequence at the 3′ end of the molecule.

Claims18

Dependent claims

A method for inhibiting Hepatitis C Virus (HCV) replication in a patient, the method comprising the steps of:

(a) administering to said patient a composition comprising a modified double-stranded RNA (dsRNA) or modified small interfering RNA (siRNA) in an amount effective to mediate RNA interference to inhibit HCV replication, wherein the modified dsRNA or modified siRNA comprises a first strand and a second strand, wherein the first strand is no more than about 30 ribonucleotides in length and the sequence of the first strand comprises the sequence of SEQ ID NO:
3 and the second strand is no more than 30 ribonucleotides in length and the sequence of the second strand comprises the sequence of SEQ ID NO:
4, wherein the modified dsRNA or modified siRNA is cholesterol-labeled, and (b) administering to said patient a cholesterol-lowering drug, wherein steps (a) and (b) can be performed simultaneously or in any order, and (c) wherein the cholesterol-lowering drug reduces the level of competing cholesterol in the serum, allowing more efficient uptake of the cholesterol-labeled modified dsRNA or modified siRNA by hepatocytes.

Dependencies are inferred from the claim text.

Modified small interfering RNA molecules and methods of use

Life of this patent

Modified small interfering RNA molecules and methods of use

Life of this patent

Abstract

Claims18