Non-liposomal systems for nucleic acid delivery
The present invention provides novel, stable lipid particles having a non-lamellar structure and comprising one or more active agents or therapeutic agents, methods of making such lipid particles, and methods of delivering and/or administering such lipid particles. More particularly, the present invention provides stable nucleic acid-lipid particles (SNALP) that have a non-lamellar structure and that comprise a nucleic acid (such as one or more interfering RNA), methods of making the SNALP, and methods of delivering and/or administering the SNALP.
1 . A composition comprising:
a plurality of nucleic acid-lipid particles, wherein each particle in the plurality of particles comprises:
(a) a nucleic acid;
(b) a titratable cationic lipid comprising three or more fatty acid or fatty alkyl chains;
(c) a non-cationic lipid; and
(d) a conjugated lipid that inhibits aggregation of particles,
wherein at least about 95% of the particles in the plurality of particles are electron-dense.
2 . The composition of claim 1 , wherein the titratable cationic lipid comprises one or more diastereomers.
3 . The composition of claim 2 , wherein the titratable cationic lipid comprises a mixture of diastereomers.
4 . The composition of claim 2 , wherein the titratable cationic lipid consists of one or more diastereomers.
5 . The composition of claim 1 , wherein the nucleic acid is RNA.
6 . The composition of claim 1 , wherein the nucleic acid is mRNA.
7 . The composition of claim 1 , wherein the titratable cationic lipid has a protonatable group with a pKa of from about 4 to about 7.
8 . The composition of claim 1 , wherein the non-cationic lipid is a mixture of (i) a phospholipid and cholesterol or (ii) a phospholipid and a cholesterol derivative.
9 . The composition of claim 1 , wherein the conjugated lipid that inhibits aggregation of particles is a polyethyleneglycol (PEG)-lipid conjugate.
10 . The composition of claim 9 , wherein the PEG-lipid conjugate is selected from the group consisting of a PEG-diacylglycerol (PEG-DAG) conjugate, a PEG dialkyloxypropyl (PEG-DAA) conjugate, a PEG-phospholipid conjugate, a PEG-ceramide (PEG-Cer) conjugate, and a mixture thereof.
11 . The composition of claim 1 , wherein the titratable cationic lipid comprises from about 50 mol % to about 85 mol % of the total lipid present in each particle.
12 . The composition of claim 1 , wherein the titratable cationic lipid comprises from about 50 mol % to about 65 mol % of the total lipid present in each particle.
13 . The composition of claim 1 , wherein the non-cationic lipid comprises a phospholipid comprising from about 2 mol % to about 15 mol % of the total lipid in each particle.
14 . The composition of claim 1 , wherein:
the titratable cationic lipid comprises from about 50 mol % to about 85 mol % of the total lipid present in each particle; and
the non-cationic lipid comprises a phospholipid comprising from about 2 mol % to about 15 mol % of the total lipid in each particle.
15 . The composition of claim 1 , wherein:
the titratable cationic lipid comprises from about 50 mol % to about 65 mol % of the total lipid present in each particle; and
the non-cationic lipid comprises a phospholipid comprising from about 2 mol % to about 15 mol % of the total lipid in each particle.
16 . The composition of claim 1 , wherein the electron-dense particles comprise an inverse hexagonal (H II ) or cubic phase structure.
17 . The composition of claim 1 , wherein greater than 95% of the particles are electron-dense.
18 . The composition of claim 1 , wherein at least 96% of the particles are electron-dense.
19 . The composition of claim 1 , wherein at least 97% of the particles are electron-dense.
20 . The composition of claim 1 , wherein at least 98% of the particles are electron-dense.
21 . The composition of claim 1 , wherein at least 99% of the particles are electron-dense.
22 . The composition of claim 1 , wherein the nucleic acid is fully encapsulated in the particles.
23 . The composition of claim 1 , wherein the particles have a mean diameter of from about 60 nm to about 130 nm.
24 . The composition of claim 1 , wherein the particles have a mean diameter of from about 70 nm to about 110 nm.
25 . The composition of claim 1 , wherein the particles have a mean diameter of from about 90 nm to about 100 nm.
26 . The composition of claim 1 , wherein the particles have a lipid:nucleic acid ratio of from about 2 to about 25.
27 . The composition of claim 1 , wherein the particles have a lipid:nucleic acid ratio of from about 3 to about 20.
28 . A pharmaceutical composition comprising the composition of claim 1 and a pharmaceutically acceptable carrier.
29 . A method for introducing a therapeutic agent into a cell, the method comprising:
contacting the cell with the composition of claim 1 .
30 . A method for the in vivo delivery of a therapeutic agent, the method comprising:
administering to a mammal the composition of claim 1 .
31 . The composition of claim 1 , wherein the titratable cationic lipid has only one titratable amino head group.
32 . The composition of claim 1 , wherein at least about 80% of the particles have the nucleic acid encapsulated therein.
33 . The composition of claim 1 , wherein at least about 90% of the particles have the nucleic acid encapsulated therein.