CHEMICALLY-MODIFIED RNAi CONSTRUCTS AND USES THEREOF

An RNAi construct that inhibits expression of a target gene sequence, comprising a sense strand and an antisense strand, wherein the antisense strand comprises a sequence that is complementary to the target gene sequence and the sense strand comprises a sequence that is sufficiently complementary to the sequence of the antisense strand to form a duplex region, wherein the RNAi construct comprises a structure represented by Formula (B):

• (B)
• 5′-(NA)x NL NL NL NL NL NL NF NL NF NF NF NF NL NL
• NL NL NL NL NT (n)y-3′
• 3′-(NB)z NL NL NL NL NL NF NL NF NL NL NL NL NF NF
• NL NF NL NF NL-5′
• wherein:
• the top strand listed in the 5′ to 3′ direction is the sense strand and the bottom strand listed in the 3′ to 5′ direction is the antisense strand;
• each NF represents a 2′-fluoro modified nucleotide;
• each NL independently represents a modified nucleotide selected from a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• NT represents a modified nucleotide selected from an abasic nucleotide, an inverted abasic nucleotide, an inverted deoxyribonucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• x is an integer from 0 to 4, provided that when x is 1, 2, 3, or 4, one or more of the NA nucleotides is a modified nucleotide independently selected from an abasic nucleotide, an inverted abasic nucleotide, an inverted deoxyribonucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide, and one or more of the NA nucleotides can be complementary to nucleotides in the antisense strand;
• y is an integer from 0 to 4, provided that when y is 1, 2, 3, or 4, one or more n nucleotides are modified or unmodified overhang nucleotides that do not base pair with nucleotides in the antisense strand;
• and
• z is an integer from 0 to 4, provided that when z is 1, 2, 3, or 4, one or more of the NB nucleotides is a modified nucleotide independently selected from a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide, and one or more of the NB nucleotides can be complementary to NA nucleotides when present in the sense strand or can be overhang nucleotides that do not base pair with nucleotides in the sense strand.

An RNAi construct that inhibits expression of a target gene sequence, comprising a sense strand and an antisense strand, wherein the antisense strand comprises a sequence that is complementary to the target gene sequence and the sense strand comprises a sequence that is sufficiently complementary to the sequence of the antisense strand to form a duplex region, wherein the RNAi construct comprises a structure represented by Formula (C):

• (C)
• 5′-(AB)x NL NL NL NL NL NL NL NL NF NL NF NF NF NF
• NL NL NM NL NM NL NT-3′
• 3′-NL NL NL NL NL NL NL NL NL NF NL NF NL NL NL NL
• NF NL NL NM NL NF NL-5′
• wherein:
• the top strand listed in the 5′ to 3′ direction is the sense strand and the bottom strand listed in the 3′ to 5′ direction is the antisense strand;
• each NF represents a 2′-fluoro modified nucleotide;
• each NL independently represents a modified nucleotide selected from a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• each NM independently represents a modified nucleotide selected from a 2′-fluoro modified nucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, BNA, and a deoxyribonucleotide;
• NT represents a modified nucleotide selected from an abasic nucleotide, an inverted abasic nucleotide, an inverted deoxyribonucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• and
• x is 0 or 1 and Ab is an inverted abasic nucleotide.

An RNAi construct that inhibits expression of a target gene sequence, comprising a sense strand and an antisense strand, wherein the antisense strand comprises a sequence that is complementary to the target gene sequence and the sense strand comprises a sequence that is sufficiently complementary to the sequence of the antisense strand to form a duplex region, wherein the RNAi construct comprises a structure represented by Formula (D):

• (D)
• 5′-(NA)x NL NL NL NL NM NL NF NF NF NF NL NL NL NL
• NL NL NL NL NT(n)y-3′
• 3′-(NB)z NL NL NL NM NL NF NL NM NL NL NM NM NM NM
• NL NM NL NF NL-5′
• wherein:
• the top strand listed in the 5′ to 3′ direction is the sense strand and the bottom strand listed in the 3′ to 5′ direction is the antisense strand;
• each NF represents a 2′-fluoro modified nucleotide;
• each NM independently represents a modified nucleotide selected from a 2′-fluoro modified nucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a bicyclic nucleic acid (BNA), and a deoxyribonucleotide;
• each NL independently represents a modified nucleotide selected from a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• NT represents a modified nucleotide selected from an abasic nucleotide, an inverted abasic nucleotide, an inverted deoxyribonucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide;
• x is an integer from 0 to 4, provided that when x is 1, 2, 3, or 4, one or more of the NA nucleotides is a modified nucleotide independently selected from an abasic nucleotide, an inverted abasic nucleotide, an inverted deoxyribonucleotide, a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide, and one or more of the NA nucleotides can be complementary to nucleotides in the antisense strand;
• y is an integer from 0 to 4, provided that when y is 1, 2, 3, or 4, one or more n nucleotides are modified or unmodified overhang nucleotides that do not base pair with nucleotides in the antisense strand;
• and
• z is an integer from 0 to 4, provided that when z is 1, 2, 3, or 4, one or more of the NB nucleotides is a modified nucleotide independently selected from a 2′-O-methyl modified nucleotide, a 2′-O-methoxyethyl modified nucleotide, a 2′-O-alkyl modified nucleotide, a 2′-O-allyl modified nucleotide, a BNA, and a deoxyribonucleotide, and one or more of the NB nucleotides can be complementary to NA nucleotides when present in the sense strand or can be overhang nucleotides that do not base pair with nucleotides in the sense strand.