Amphipathic co-oligomers for the delivery of siRNA
Co-oligomer compounds, complexes of the same with polyanions, such as siRNAs, and methods for using the same are provided. the delivery of polynucleotides, into a cell. The subject co-oligomers include at least a liphopilic monomer and at least a hydrophilic monomer (e.g., a guanidinium containing monomer). In some embodiments, the co-oligomer compounds are capable of complexing a siRNA of interest, thereby increasing the cell permeability of the siRNA, prior to release of the siRNA into the cell. In some embodiments, the subject method is a method of delivery a siRNA into a cell. In some embodiments, the subject method is a method of reducing expression of a protein target of a siRNA of interest. The subject co-oligomer/siRNA complexes may be formulated and administered to a subject to treat a condition resulting from expression of a protein target of the siRNA of interest.
1. A composition comprising:
a siRNA; and
a co-oligomer having a length of 40 monomers or less that is a random co-oligomer or a block co-oligomer of lipophilic monomers and hydrophilic monomers, wherein the co-oligomer is described by formula (I):
wherein:
Y is an initiator group;
p1 and q1 are each independently 0 or 1, where p1+q1≧1;
p2 and q2 are each independently 0 or 1, where p2+q2≧1;
each Z 1 and Z 2 is independently a linking group;
each and R 11 and R 12 is independently selected from hydrogen and a lower alkyl;
m and n represent a number of lipophilic or hydrophilic monomers in the random or block co-oligomer and are independently an integer from 1 to 30, wherein the sum of m and n is 40 monomers or less; and
each R 1 and R 2 is independently a sidechain group, wherein:
one of R 1 and R 2 is a lipophilic sidechain of the lipophilic monomers; and
the other of R 1 and R 2 is -L-Z 3 where L is a linker and Z 3 is a hydrophilic positively charged group of the hydrophilic monomers.
2. The composition of claim 1 , wherein Y is selected from PhCH 2 X—, RCOX— and Ar—X—, wherein X is O, S or NH, and R is an alkyl or an aryl.
3. The composition of claim 1 , wherein p1 and q1 are each 1.
4. The composition of claim 1 , wherein either p1 is 1 and q1 is 0 or p1 is 0 and q1 is 1.
5. The composition of claim 1 , wherein p2 and q2 are each 1.
6. The composition of claim 1 , wherein either p2 is 1 and q2 is 0 or p2 is 0 and q2 is 1.
7. The composition of claim 1 , wherein each Z 1 and Z 2 is an ester linking group (—CO 2 —).
8. The composition of claim 1 , wherein each R 11 and R 12 is methyl.
9. The composition of claim 1 , wherein each lipophilic sidechain is independently a linear alkyl having from 7 to 24 carbon atoms, or a branched alkyl having from 7 to 24 carbon atoms.
10. The composition of claim 1 , wherein each lipophilic sidechain is dodecyl.
11. The composition of claim 1 , wherein L is a C 1 -C 6 linker and Z 3 is a guanidinium group.
12. The composition of claim 1 , wherein each R 1 is a lipophilic sidechain and each R 2 is -L-Z 3 .
13. The composition of claim 1 , wherein each R 1 is -L-Z 3 and each R 2 is a lipophilic sidechain.
14. The composition of claim 1 , wherein the co-oligomer is a random co-oligomer of lipophilic and hydrophilic monomers having a length of about 20 or less.
15. The composition of claim 14 , wherein the ratio of lipophilic to hydrophilic monomers ranges from 0.4 to 2.5.
16. The composition of claim 1 , wherein the co-oligomer comprises a block of 8 or less lipophilic monomers adjacent to a block of 10 or less hydrophilic monomers, wherein the co-oligomer is described by formula (III):
wherein:
m is 8 or less;
n is 10 or less;
R 21 is the lipophilic sidechain; and
t is an integer from 1 to 6.
17. The composition of claim 16 , wherein Y is selected from PhCH 2 X—, RCOX— and Ar—X—, where X is O , S or NH, and R is an alkyl or an aryl.
18. The composition of claim 16 , wherein each Z 1 and Z 2 is an ester linking group (—CO 2 —), an amide linking group (—CONR—) where R is H or an alkyl, or a thioester linking group (—C(═O)S—).
19. The composition of claim 16 , wherein each and R 11 and R 12 is methyl.
20. The composition of claim 16 , wherein each R 21 is independently a linear alkyl having from 7 to 24 carbon atoms, or a branched alkyl having from 7 to 24 carbon atoms.
21. The composition of claim 16 , wherein each R 21 is dodecyl.
22. The composition of claim 16 , wherein t is 2.
23. The composition of claim 16 , wherein m and n are each independently 5 or less.
24. The composition of claim 16 , wherein the co-oligomer is described by formula (IV):
wherein:
m is 8 or less;
n is 10 or less;
t is an integer from 1 to 6; and
X − is a counterion.
25. The composition of claim 24 , wherein Y is PhCH 2 O—.
26. The composition of claim 24 , wherein each R 21 is dodecyl, or hexyl.
27. The composition of claim 24 , wherein m and n are each independently 5 or less.
28. A pharmaceutical composition comprising the composition of claim 1 and a pharmaceutically acceptable excipient.
29. A method for intracellular delivery of a siRNA to a cell, the method comprising:
complexing the siRNA with a co-oligomer having a length of 40 monomers or less that is a random co-oligomer or a block co-oligomer of lipophilic and hydrophilic monomers, wherein the co-oligomer is described by formula (I):
wherein:
Y is an initiator group;
p1 and q1 are each independently 0 or 1, where p1+q1≧1;
p2 and q2 are each independently 0 or 1, where p2+q2≧1;
each Z 1 and Z 2 is independently a linking group;
each and R 11 and R 12 is independently selected from hydrogen and a lower alkyl;
m and n represent a number of lipophilic or hydrophilic monomers in the random or block co-oligomer and are each independently an integer from 1 to 30, wherein the sum of m and n is 40 monomers or less; and
each R 1 and R 2 is independently a sidechain group, wherein:
one of R 1 and R 2 is a lipophilic sidechain of the lipophilic monomers; and
the other of R 1 and R 2 is -L-Z 3 where L is a linker and Z 3 is a hydrophilic positively charged group of the hydrophilic monomers;
to produce a siRNA / co-oligomer complex; and
contacting the cell with the complex.
30. A method for inhibiting the expression of a target protein in a cell, the method comprising contacting the cell with an effective amount of the composition of claim 1 .
31. The method of claim 30 , wherein the target protein is a target of the siRNA of the composition.
32. A method of treating a subject for a disease condition, the method comprising administering to the subject an effective amount of the composition of claim 1 ;
to treat the subject for the disease condition.
33. The method of claim 32 , wherein the disease condition results from the expression of a protein target of the siRNA of the composition.