Compositions and methods for silencing ebola virus gene expression

Abstract

The present invention provides compositions comprising therapeutic nucleic acids (e.g., interfering RNA such as siRNA) that target Ebola virus (EBOV) gene expression and methods of using such compositions to silence EBOV gene expression. More particularly, the invention provides unmodified and chemically modified interfering RNA which silence EBOV gene expression and methods of use thereof, e.g., for preventing or treating EBOV infections caused by one or more EBOV species such as Zaire EBOV. The invention also provides serum-stable nucleic acid-lipid particles comprising one or more interfering RNA molecules, a cationic lipid, and a non-cationic lipid, which can further comprise a conjugated lipid that inhibits aggregation of particles. Methods of silencing EBOV gene expression by administering one or more interfering RNA molecules to a mammalian subject are also provided.

1 . A composition comprising at least two interfering RNA selected from the group consisting of:
 (a) a first interfering RNA that silences Ebola virus L-pol expression, wherein the first interfering RNA comprises an antisense strand comprising the following sequence: 5′-UUUAUAUACAGCUUCGUAC-3′;   (b) a second interfering RNA that silences Ebola virus VP24 expression, wherein the second interfering RNA comprises an antisense strand comprising the following sequence: 5′-UUUGCAUUCGUGUCGAGGA-3′; and   (c) a third interfering RNA that silences Ebola virus VP35 expression, wherein the third interfering RNA comprises an antisense strand comprising the following sequence: 5′-AUGAUGUCCAAUGAGUUGC-3′.   
     
     
         2 . The composition of  claim 1 , wherein the composition comprises the first and second interfering RNA, the first and third interfering RNA, the second and third interfering RNA, or the first, second, and third interfering RNA. 
     
     
         3 . The composition of  claim 1 , wherein the first interfering RNA comprises an siRNA. 
     
     
         4 . The composition of  claim 1 , wherein the second interfering RNA comprises an siRNA. 
     
     
         5 . The composition of  claim 1 , wherein the third interfering RNA comprises an siRNA. 
     
     
         6 . The composition of  claim 3 , wherein the siRNA comprises a double-stranded region of about 19 to about 25 nucleotides in length. 
     
     
         7 . The composition of  claim 6 , wherein one or more of the nucleotides in the double-stranded region of the siRNA comprise modified nucleotides. 
     
     
         8 . The composition of  claim 7 , wherein the modified nucleotides comprise 2′-O-methyl (2′OMe) nucleotides. 
     
     
         9 . The composition of  claim 8 , wherein the 2′OMe nucleotides comprise at least one, two, three, four, five, six, seven, eight, nine, ten, or eleven 2′OMe-guanosine nucleotides, 2′OMe-uridine nucleotides, or mixtures thereof. 
     
     
         10 . The composition of  claim 7 , wherein less than about 50% of the nucleotides in the double-stranded region comprise modified nucleotides. 
     
     
         11 . The composition of  claim 3 , wherein the siRNA comprises a 3′ overhang in one or both strands of the siRNA. 
     
     
         12 . The composition of  claim 11 , wherein one or more of the nucleotides in the 3′ overhang of one or both strands comprise modified nucleotides. 
     
     
         13 . The composition of  claim 12 , wherein the modified nucleotides comprise 2′-O-methyl (2′OMe) nucleotides. 
     
     
         14 . The composition of  claim 13 , wherein the 2′OMe nucleotides comprise at least one, two, three, or four 2′OMe-guanosine nucleotides, 2′OMe-uridine nucleotides, or mixtures thereof. 
     
     
         15 . The composition of  claim 1 , wherein the first interfering RNA further comprises a sense strand comprising the following sequence: 5′-GUACGAAGCUGUAUAUAAA-3′. 
     
     
         16 . The composition of  claim 15 , wherein the antisense strand comprises a 5′-TT-3′ overhang and the sense strand comprises a 5′-TT-3′ overhang. 
     
     
         17 . The composition of  claim 1 , wherein the first interfering RNA comprises an antisense strand comprising one of the antisense strand sequences set forth in Table 2. 
     
     
         18 . The composition of  claim 1 , wherein the first interfering RNA comprises an antisense strand comprising at least 15 contiguous nucleotides of one of the antisense strand sequences set forth in Table 2. 
     
     
         19 . The composition of  claim 1 , wherein the first interfering RNA comprises an antisense strand comprising nucleotides 1-19 of one of the antisense strand sequences set forth in Table 2. 
     
     
         20 . The composition of  claim 1 , wherein the first interfering RNA further comprises a sense strand comprising one of the sense strand sequences set forth in Table 1. 
     
     
         21 - 88 . (canceled)