siRNA SILENCING OF FILOVIRUS GENE EXPRESSION

Abstract

The present invention provides siRNA molecules that target Filovirus gene expression and methods of using such siRNA molecules to silence Filovirus gene expression. The present invention also provides nucleic acid-lipid particles that target Filovirus gene expression comprising an siRNA that silences Filovirus gene expression, a cationic lipid, and a non-cationic lipid.

1 . An siRNA molecule for silencing Ebola virus L-polymerase (L-pol) expression comprising a double-stranded sequence of about 19 to about 25 nucleotides in length, wherein said siRNA molecule comprises an antisense strand sequence comprising SEQ ID NO:24. 
     
     
         2 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises an antisense strand sequence consisting of SEQ ID NO:24. 
     
     
         3 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises a sense strand sequence comprising SEQ ID NO:23. 
     
     
         4 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises a sense strand sequence consisting of SEQ ID NO:23. 
     
     
         5 . The siRNA molecule in accordance with  claim 1 , wherein said double-stranded sequence comprises a hairpin loop structure. 
     
     
         6 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises 3′ overhangs of about 1 to about 4 nucleotides on one or both sides of the double-stranded sequence. 
     
     
         7 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises at least one modified nucleotide. 
     
     
         8 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises at least one modified nucleotide in one or both strands of the double-stranded sequence. 
     
     
         9 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises at least one 2′-O-methyl (2′OMe) nucleotide. 
     
     
         10 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises at least one 2′OMe nucleotide selected from the group consisting of a 2′OMe-guanosine nucleotide, 2′OMe-uridine nucleotide, 2′OMe-adenosine nucleotide, 2′OMe-cytosine nucleotide, and mixtures thereof. 
     
     
         11 . The siRNA molecule in accordance with  claim 1 , wherein said siRNA molecule comprises at least one 2′OMe-guanosine nucleotide and at least one 2′OMe-uridine nucleotide. 
     
     
         12 . A pharmaceutical composition comprising an siRNA molecule in accordance with  claim 1  and a pharmaceutically acceptable carrier. 
     
     
         13 . A nucleic acid-lipid particle comprising: an siRNA molecule in accordance with  claim 1 ; a cationic lipid; and a non-cationic lipid. 
     
     
         14 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said cationic lipid is a member selected from the group consisting of N,N-dioleyl-N,N-dimethylammonium chloride (DODAC), N,N-distearyl-N,N-dimethylammonium bromide (DDAB), N-(1-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride (DOTAP), N-(1-(2,3-dioleyloxy)propyl)-N,N,N-trimethylammonium chloride (DOTMA), N,N-dimethyl-2,3-dioleyloxypropylamine (DODMA), 1,2-DiLinoleyloxy-N,N-dimethylaminopropane (DLinDMA), 1,2-Dilinolenyloxy-N,N-dimethylaminopropane (DLenDMA), and a mixture thereof. 
     
     
         15 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said cationic lipid comprises DLinDMA. 
     
     
         16 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid comprises an anionic lipid. 
     
     
         17 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid comprises a neutral lipid. 
     
     
         18 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid is a member selected from the group consisting of dipalmitoylphosphatidylcholine (DPPC), distearoylphosphatidylcholine (DSPC), dioleoylphosphatidylethanolamine (DOPE), palmitoyloleoyl-phosphatidylcholine (POPC), palmitoyloleoyl-phosphatidylethanolamine (POPE), palmitoyloleyol-phosphatidylglycerol (POPG), dipalmitoyl-phosphatidylethanolamine (DPPE), dimyristoyl-phosphatidylethanolamine (DMPE), distearoyl-phosphatidylethanolamine (DSPE), monomethyl-phosphatidylethanolamine, dimethyl-phosphatidylethanolamine, dielaidoyl-phosphatidylethanolamine (DEPE), stearoyloleoyl-phosphatidylethanolamine (SOPE), egg phosphatidylcholine (EPC), cholesterol, and a mixture thereof. 
     
     
         19 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid comprises DPPC. 
     
     
         20 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid comprises DPPC and cholesterol. 
     
     
         21 . The nucleic acid-lipid particle in accordance with  claim 13 , further comprising a conjugated lipid that inhibits aggregation of particles. 
     
     
         22 . The nucleic acid-lipid particle in accordance with  claim 21 , wherein said conjugated lipid that inhibits aggregation of particles is a member selected from the group consisting of a polyethyleneglycol (PEG)-lipid conjugate, a polyamide (ATTA)-lipid conjugate, and a mixture thereof. 
     
     
         23 . The nucleic acid-lipid particle in accordance with  claim 22 , wherein said PEG-lipid conjugate is a member selected from the group consisting of a PEG-diacylglycerol conjugate, a PEG-dialkyloxypropyl (PEG-DAA) conjugate, a PEG-phospholipid conjugate, a PEG-ceramide conjugate, and a mixture thereof. 
     
     
         24 . The nucleic acid-lipid particle in accordance with  claim 22 , wherein said conjugated lipid that inhibits aggregation of particles comprises a PEG-DAA conjugate. 
     
     
         25 . The nucleic acid-lipid particle in accordance with  claim 24 , wherein said PEG-DAA conjugate is a member selected from the group consisting of a PEG-dilauryloxypropyl (C 12 ) conjugate, a PEG-dimyristyloxypropyl (C 14 ) conjugate, a PEG-dipalmityloxypropyl (C 16 ) conjugate, and a PEG-distearyloxypropyl (C 18 ) conjugate. 
     
     
         26 . The nucleic acid-lipid particle in accordance with  claim 24 , wherein said PEG-DAA conjugate comprises a PEG-dimyristyloxypropyl (C 14 ) conjugate. 
     
     
         27 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said cationic lipid comprises from about 2 mol % to about 60 mol % of the total lipid present in said particle. 
     
     
         28 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said cationic lipid comprises from about 20 mol % to about 50 mol % of the total lipid present in said particle. 
     
     
         29 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said non-cationic lipid comprises from about 5 mol % to about 90 mol % of the total lipid present in said particle. 
     
     
         30 . The nucleic acid-lipid particle in accordance with  claim 21 , wherein said conjugated lipid that inhibits aggregation of particles comprises from 0 mol % to about 20 mol % of the total lipid present in said particle. 
     
     
         31 . The nucleic acid-lipid particle in accordance with  claim 21 , wherein said conjugated lipid that inhibits aggregation of particles comprises from about 0.5 mol % to about 20 mol % of the total lipid present in said particle. 
     
     
         32 . The nucleic acid-lipid particle in accordance with  claim 21 , wherein said conjugated lipid that inhibits aggregation of particles comprises about 2 mol % of the total lipid present in said particle. 
     
     
         33 . The nucleic acid-lipid particle in accordance with  claim 13 , further comprising cholesterol. 
     
     
         34 . The nucleic acid-lipid particle in accordance with  claim 33 , wherein the cholesterol comprises from about 10 mol % to about 60 mol % of the total lipid present in said particle. 
     
     
         35 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said siRNA molecule in said nucleic acid-lipid particle is not substantially degraded after exposure of said particle to a nuclease at 37° C. for 20 minutes. 
     
     
         36 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said siRNA molecule in said nucleic acid-lipid particle is not substantially degraded after incubation of said particle in serum at 37° C. for 30 minutes. 
     
     
         37 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said siRNA molecule is fully encapsulated in said nucleic acid-lipid particle. 
     
     
         38 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said particle has a siRNA:lipid ratio of from about 0.01 to about 0.2. 
     
     
         39 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said particle has a siRNA:lipid ratio of from about 0.02 to about 0.1. 
     
     
         40 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said particle has a siRNA:lipid ratio of about 0.04. 
     
     
         41 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said particle has a median diameter of from about 50 nm to about 150 nm. 
     
     
         42 . The nucleic acid-lipid particle in accordance with  claim 13 , wherein said particle has a median diameter of from about 70 nm to about 90 nm. 
     
     
         43 . A pharmaceutical composition comprising a nucleic acid-lipid particle in accordance with  claim 13  and a pharmaceutically acceptable carrier.