IRNA agents with biocleavable tethers
View Patent ↗The invention relates to iRNA agents, which preferably include a monomer in which the ribose moiety has been replaced by a moiety other than ribose that further includes a tether having one or more linking groups, in which at least one of the linking groups is a cleavable linking group. The tether in turn can be connected to a selected moiety, e.g., a ligand, e.g., a targeting or delivery moiety, or a moiety which alters a physical property. The cleavable linking group is one which is sufficiently stable outside the cell such that it allows targeting of a therapeutically beneficial amount of an iRNA agent (e.g., a single stranded or double stranded iRNA agent), coupled by way of the cleavable linking group to a targeting agent—to targets cells, but which upon entry into a target cell is cleaved to release the iRNA agent from the targeting agent.
1. An iRNA agent comprising a first strand and optionally a second strand, wherein at least one subunit having a formula (I) is incorporated into at least one of the strands:
wherein:
X is N(CO)R 7 , or NR 7 ;
Each of R 1 , R 3 , and R 9 is, independently, H, OH, OR a , OR b , CH 2 OR a , or CH 2 OR b , provided that at least one of R 1 , R 3 , and R 9 is OH, OR a , or OR b and that at least one of R 1 , R 3 , and R 9 is CH 2 OR a , or CH 2 OR b ;
R 7 is T-R d , in which T is a tether comprising a hydrocarbon chain and one or more linking groups, wherein at least one of the linking groups is cleavable; and R d is a steroid radical, wherein the tether selected from the group consisting of
each of A and C is, independently, O or S; and
B is OH, O − , or
2. The agent of claim 1 , wherein at least one of the linking groups is cleaved at least about 100 times faster under intracellular conditions than under extracellular conditions.
3. The agent of claim 1 , wherein at least one of the linking groups is cleaved at least about 50 times faster under intracellular conditions than under extracellular conditions.
4. The agent of claim 1 , wherein at least one of the linking groups is cleaved at least about 10 times faster under intracellular conditions than under extracellular conditions.
5. The agent of claim 1 , wherein R 1 is CH 2 OR b and R 9 is OR a or OH.
6. The agent of claim 5 , wherein R 1 and R 9 are cis.
7. The agent of claim 5 , wherein R 1 and R 9 are trans.
8. The agent of claim 1 , wherein R 1 is OR a and R 9 is CH 2 OR b .
9. The agent of claim 8 , wherein R 1 and R 9 are cis.
10. The agent of claim 8 , wherein R 1 and R 9 are trans.
11. The agent of claim 1 , wherein R 1 is CH 2 OR b and R 9 is OR b .
12. The agent of claim 1 , wherein R 1 is CH 2 OR a and R 9 is OR b .
13. The agent of claim 1 , wherein R 1 is OR b and R 9 is CH 2 OR b .
14. The agent of claim 1 , wherein R 1 is OR b and R 9 is CH 2 OR a .
15. The agent of claim 1 , wherein the R d steroid radical is a cholesterol radical.
16. The agent of claim 1 , wherein the iRNA agent is a single-stranded iRNA agent.
17. The agent of claim 16 , wherein the single-stranded iRNA agent is an siRNA agent.
18. The agent of claim 17 , wherein R d is a cholesterol radical.
19. The agent of claim 16 , wherein the iRNA agent is less than 30 nucleotides in length.
20. The agent of claim 19 , wherein the iRNA agent is 21-23 nucleotides in length.
21. The agent of claim 1 , wherein the iRNA agent is a double-stranded iRNA agent comprising a first strand and a second strand.
22. The agent of claim 21 , wherein the double-stranded iRNA agent is an siRNA agent.
23. The agent of claim 22 , wherein R d is a cholesterol radical.
24. The agent of claim 21 , wherein the iRNA agent is less than 30 nucleotides in length.
25. The agent of claim 24 , wherein the iRNA agent is 21-23 nucleotides in length.
26. The agent of claim 21 , wherein the at least one subunit of formula (I) is incorporated into both strands.
27. The agent of claim 1 , wherein one of R 3 or R 9 is OH.
28. The agent of claim 1 , wherein X is N(CO)R 7 .
29. The agent of claim 1 , wherein X is NR 7 .
30. The agent of claim 1 , wherein R d is uvaol.
31. The agent of claim 1 , wherein R d is hecigenin.
32. The agent of claim 1 , wherein R d is diosgenin.
33. The agent of claim 1 , wherein R d is cholic acid.
34. The agent of claim 1 , wherein R d is bile acid.
35. The agent of claim 1 , wherein R d is dihydrotestosterone.
36. The agent of claim 1 , wherein R d is a cholesteryl residue.
37. The agent of claim 1 , wherein R d is O3-(oleoyl)lithocholic acid radical.
38. The agent of claim 1 , wherein R d is an O3-(oleoyl) cholenic acid radical.
39. The agent of claim 1 , wherein A is O in each occurrence.
40. The agent of claim 1 , wherein A is S in at least one occurrence.
41. The agent of claim 5 , wherein R 1 is CH 2 OR b and R 9 is OH.