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US-12622979-B2 - Lipid nanoparticle used for delivering nucleic acid to brain tissue

US12622979B2US 12622979 B2US12622979 B2US 12622979B2US-12622979-B2

Abstract

The present invention provides a lipid nanoparticle used for delivering a nucleic acid to a brain tissue, including an ionic lipid represented by the formula (1), phospholipid, cholesterol, and a dimyristoylglycerol PEG with a number average molecular weight of PEG chain of 4,000 to 6,000, wherein an amount of the dimyristoylglycerol PEG is 1 to 6 mol % with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol (the symbols in the formula (1) are as defined in the specification)

Inventors

  • Kota TANGE
  • Hiroki Yoshioka
  • Yuta Nakai
  • Hidetaka Akita
  • Yu SAKURAI
  • Hiroki Tanaka
  • Shoya FUJITA

Assignees

  • NOF CORPORATION
  • NATIONAL UNIVERSITY CORPORATION CHIBA UNIVERSITY

Dates

Publication Date
20260512
Application Date
20220926
Priority Date
20210930

Claims (20)

  1. 1 . A lipid nanoparticle used for delivering a nucleic acid to a brain tissue, comprising wherein R 1a and R 1b are each independently an alkylene group having 1 to 6 carbon atoms, X a and X b are each independently an acyclic alkyl tertiary amino group having 1 to 6 carbon atoms and one tertiary amino group, or a cyclic alkylene tertiary amino group having 2 to 5 carbon atoms and 1 to 2 tertiary amino groups, R 2a and R 2b are each independently an alkylene group or an oxydialkylene group each having not more than 8 carbon atoms, Y a and Y b are each independently an ester bond, an amide bond, a carbamate bond, an ether bond or a urea bond, Z a and Z b are each independently a divalent group derived from an aromatic compound having 3 to 16 carbon atoms and at least one aromatic ring, and optionally having a hetero atom, and R 3a and R 3b are each independently a residue derived from a reaction product of a liposoluble vitamin having a hydroxyl group, and succinic anhydride or glutaric anhydride, or a residue derived from a reaction product of a sterol derivative having a hydroxyl group, and succinic anhydride or glutaric anhydride, or an aliphatic hydrocarbon group having 12 to 22 carbon atoms, (ii) phospholipid, (iii) cholesterol, and (iv) a dimyristoylglycerol PEG represented by the formula (2): CH 2 (OR 6 )—CH(OR 7 )—CH 2 (OR 8 ) (2) wherein two of R 6 , R 7 , and R 8 are myristoyl groups, and the remaining one is an alkyl group having 1 to 6 carbon atoms connected via a polyethylene glycol chain with a number average molecular weight of 4,000 to 6,000, wherein an amount of the dimyristoylglycerol PEG represented by the formula (2) is 1 to 6 mol % with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol.
  2. 2 . The lipid nanoparticle according to claim 1 , wherein lipids constituting the lipid nanoparticle consist of the ionic lipid represented by the formula (1), the phospholipid, the cholesterol, and the dimyristoylglycerol PEG represented by the formula (2).
  3. 3 . The lipid nanoparticle according to claim 2 , wherein the ionic lipid represented by the formula (1) is an ionic lipid represented by the following formula:
  4. 4 . The lipid nanoparticle according to claim 3 , wherein the phospholipid is 1,2-dioleoyl-sn-glycero-3-phosphocholine.
  5. 5 . The lipid nanoparticle according to claim 4 , wherein an amount of the ionic lipid represented by the formula (1) is 15 to 70 mol %, an amount of the phospholipid is 5 to 25 mol %, and an amount of the cholesterol is 25 to 80 mol %, with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol.
  6. 6 . The lipid nanoparticle according to claim 2 , wherein the phospholipid is 1,2-dioleoyl-sn-glycero-3-phosphocholine.
  7. 7 . The lipid nanoparticle according to claim 6 , wherein an amount of the ionic lipid represented by the formula (1) is 15 to 70 mol %, an amount of the phospholipid is 5 to 25 mol %, and an amount of the cholesterol is 25 to 80 mol %, with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol.
  8. 8 . The lipid nanoparticle according to claim 2 , wherein an amount of the ionic lipid represented by the formula (1) is 15 to 70 mol %, an amount of the phospholipid is 5 to 25 mol %, and an amount of the cholesterol is 25 to 80 mol %, with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol.
  9. 9 . The lipid nanoparticle according to claim 1 , wherein the ionic lipid represented by the formula (1) is an ionic lipid represented by the following formula:
  10. 10 . The lipid nanoparticle according to claim 1 , wherein the phospholipid is 1,2-dioleoyl-sn-glycero-3-phosphocholine.
  11. 11 . The lipid nanoparticle according to claim 1 , wherein an amount of the ionic lipid represented by the formula (1) is 15 to 70 mol %, an amount of the phospholipid is 5 to 25 mol %, and an amount of the cholesterol is 25 to 80 mol %, with respect to the total of the ionic lipid represented by the formula (1), the phospholipid, and the cholesterol.
  12. 12 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 1 that encapsulates the nucleic acid to a subject.
  13. 13 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 2 that encapsulates the nucleic acid to a subject.
  14. 14 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 9 that encapsulates the nucleic acid to a subject.
  15. 15 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 10 that encapsulates the nucleic acid to a subject.
  16. 16 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 11 that encapsulates the nucleic acid to a subject.
  17. 17 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 3 that encapsulates the nucleic acid to a subject.
  18. 18 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 4 that encapsulates the nucleic acid to a subject.
  19. 19 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 5 that encapsulates the nucleic acid to a subject.
  20. 20 . A method for delivering a nucleic acid to a brain tissue, comprising transnasally administering the lipid nanoparticle according to claim 6 that encapsulates the nucleic acid to a subject.

Description

TECHNICAL FIELD The present invention relates to lipid nanoparticles used to deliver nucleic acids to brain tissues, and methods for delivering nucleic acids to brain tissues. BACKGROUND ART For practicalization of nucleic acid therapy, an effective and safe nucleic acid delivery carrier is demanded. While virus vectors are nucleic acid delivery carriers with good expression efficiency, they have practical problems from the aspect of safety. Therefore, the development of non-viral nucleic acid delivery carriers that can be used more safely is ongoing. Among them, lipid nanoparticles that are carriers using ionic lipids are non-viral nucleic acid delivery carriers most generally used at present. Ionic lipids are largely constituted of amine moiety and lipid moiety. The amine moiety, which is protonated under acidic conditions, interacts electrostatically with nucleic acids, which are polyanions, to form lipid nanoparticles, which promotes uptake into cells and delivers nucleic acids into cells. A known ionic lipid that is generally widely used is, for example, 1,2-dioleoyl-3-dimethylammonium propane (DODAP). It is known that by combining known ionic lipids with phospholipids, cholesterol, and PEG lipids, lipid nanoparticles can be formed and nucleic acids can be delivered into cells (Non Patent Literature 1). Patent Literature 1 describes an ionic lipid having a structure in which compounds consisting of one or two amine moieties and one lipid moiety are connected by a biodegradable disulfide bond. This literature states that the ionic lipid can improve pharmacokinetics such as blood stability and tumor targeting, and that by changing the structure around the amine moiety, the pKa of a lipid membrane structure can be adjusted to a value advantageous for endosomal escape in cells, and further that it has the effect of dissociating nucleic acids from lipid membrane structures by utilizing the cleavage of disulfide bonds within cells. In fact, since it shows higher nucleic acid delivery efficiency compared to a known ionic lipid DODAP, it is clear that this ionic lipid can achieve improvement of the intracellular dynamics such as improvement of the delivery efficiency of nucleic acids into the cytoplasm and the like. In Patent Literature 2, a lipid membrane structure is shown that has enhanced ability to fuse with endosomal membrane and has further improved efficiency of nucleic acid introduction into the cytoplasm, by using an ionic lipid having, in addition to a tertiary amine moiety and disulfide bond, an aromatic ring introduced near the lipid moiety. As described above, ionic lipids with improved intracellular dynamics have been developed by increasing endosomal escape efficiency and membrane fusion ability. On the other hand, in order for lipid nanoparticles made of ionic lipids to exhibit more practical effects as nucleic acid delivery carriers in vivo, directivity to target organs and cells is demanded. one of the PEG lipids widely used in lipid nanoparticles is dimyristoylglycerol PEG (DMG-PEG). It is known that when lipid nanoparticles using DMG-PEG with a PEG number average molecular weight of 2000 are administered into the blood, the PEG lipids gradually dissociate from the lipid nanoparticles in the blood, and apolipoprotein E (ApoE) present in the blood adheres to lipid nanoparticles, thus increasing its accumulation in the liver where ApoE receptors are expressed (Non Patent Literature 2). As lipid nanoparticles that have been given directivity to organs other than the liver, for example, lipid nanoparticles obtained using, as a PEG lipid, distearoylglycerol PEG (DSG-PEG) having a stearic acid-derived hydrophobic group, instead of DMG-PEG having a myristic acid-derived hydrophobic group can be mentioned (Non Patent Literature 3). Compared to DMG-PEG, DSG-PEG does not easily dissociate from lipid nanoparticles in the blood. Therefore, DSG-PEG avoids adhesion of ApoE in the blood, suppresses accumulation in the liver, and shows high retention in the blood, as a result of which increases accumulation in tumors. As described above, there are known multiple lipid nanoparticles with improved intracellular dynamics and multiple lipid nanoparticles with controlled organ accumulation after intravenous injection by changing PEG lipid, which is one of the constituent components. However, there is a wide variety of organs and cells that can be targets for drug discovery, and the development of lipid nanoparticles having directivity to various organs and cells is demanded. Among organs, the brain is an organ into which delivery of drug is extremely difficult because the transfer of substances from the blood to the brain tissue is strictly restricted by the blood-brain barrier that exists in the intracerebral capillary. Because of this, cerebral neurosis includes many intractable diseases for which no effective treatment method exists. Thus, lipid nanoparticles to efficiently deliver therapeutic nucleic acids