Lipid formulations for delivery of messenger RNA

1. A method of delivery of messenger RNA (mRNA) in vivo, comprising administering to a subject in need of delivery a composition comprising an mRNA that encodes Factor IX (FIX), wherein said mRNA is encapsulated within a liposome such that the administering of the composition results in the expression of the protein encoded by the mRNA in vivo; and

wherein the liposome comprises a cationic lipid of formula I-g:

or a pharmaceutically acceptable salt thereof,

wherein:

R L is C 1-50 alkyl, C 2-50 alkenyl, or C 2-50 alkynyl, and

wherein the mRNA has a length of or greater than about 0.5 kb.

2. The method of claim 1 , wherein R L is C 8-12 alkyl.

3. The method of claim 2 , wherein R L is linear —C 8 H 17 , —C 9 H 19 , —C 10 H 21 , —C 11 H 23 , or —C 12 H 25 .

4. The method of claim 3 , wherein R L is linear —C 8 H 17 or —C 10 H 21 .

5. The method of claim 4 , wherein the cationic lipid is cKK-E12:

6. The method of claim 1 , wherein the liposome further comprises one or more non-cationic lipids, one or more cholesterol-based lipids and/or one or more PEG-modified lipids.

7. The method of claim 6 , wherein the one or more non-cationic lipids are selected from DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine), DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine), DOPE (1,2-dioleyl-sn-glycero-3-phosphoethanolamine), DOPC (1,2-dioleyl-sn-glycero-3-phosphotidylcholine) DPPE (1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine), DMPE (1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine), DOPG (1,2-dioleoyl-sn-glycero-3-phospho-(1′-rac-glycerol)).

8. The method of claim 6 , wherein the one or more cholesterol-based lipids are cholesterol and/or PEGylated cholesterol.

9. The method of claim 6 , wherein the one or more PEG-modified lipids comprise a poly(ethylene) glycol chain of up to 5 kDa in length covalently attached to a lipid with alkyl chain(s) of C 6 -C 20 length.

10. The method of claim 6 , wherein the liposome comprises cKK-E12, DOPE, cholesterol and DMG-PEG2K.

11. The method of claim 1 , wherein the cationic lipid constitutes about 30-50% of the liposome by molar ratio.

12. The method of claim 11 , wherein the ratio of cKK-E12:DOPE:cholesterol:DMG-PEG2K is approximately 40:30:20:10, 40:30:25:5, or 40:32:25:3 by molar ratio.

13. The method of claim 1 , wherein the liposome has a size less than about 250 nm, 200 nm, 150 nm, 100 nm, 75 nm, or 50 nm.

14. The method of claim 1 , wherein the expression of the protein encoded by the mRNA is detectable in liver, kidney, heart, spleen, serum, brain, skeletal muscle, lymph nodes, skin, and cerebrospinal fluid.

15. The method of claim 1 , wherein the expression of the protein encoded by the mRNA is detectable 3, 6, 12, or 24 hours after the administration or 1 week after the administration.

16. The method of claim 1 , wherein the mRNA has a length of or greater than about 1 kb, 1.5 kb, 2 kb, 2.5 kb, 3 kb, 3.5 kb, 4 kb, 4.5 kb, or 5 kb.

17. The method of claim 1 , wherein the mRNA comprises one or more modified nucleotides.

18. The method of claim 17 , wherein the one or more modified nucleotides comprise pseudouridine, N-1-methyl-pseudouridine, 2-aminoadenosine, 2-thiothymidine, inosine, pyrrolo-pyrimidine, 3-methyl adenosine, 5-methylcytidine, C-5 propynyl-cytidine, C-5 propynyl-uridine, 2-aminoadenosine, C5-bromouridine, C5-fluorouridine, C5-iodouridine, C5-propynyl-uridine, C5-propynyl-cytidine, C5-methylcytidine, 2-aminoadenosine, 7-deazaadenosine, 7-deazaguanosine, 8-oxoadenosine, 8-oxoguanosine, 0(6)-methylguanine, and/or 2-thiocytidine.

19. The method of claim 1 , wherein the mRNA is unmodified.

20. The method of claim 1 , wherein the mRNA encodes a therapeutic protein.