Polymer-encapsulated reverse micelles

• US 8,193,334 B2
• Filed: 10/05/2009
• Issued: 06/05/2012
• Est. Priority Date: 04/04/2007
• Status: Active Grant

• Current Assignee: Brigham and Women's Hospital Incorporated, Massachusetts Institute of Technology
• Original Assignee: Brigham and Women's Hospital Incorporated, Massachusetts Institute of Technology
• Inventors: Radovic-Moreno, Aleksandar F., Zhang, Liangfang, Langer, Robert S., Farokhzad, Omid C.
• Primary Examiner(s): Bowman, Amy
• Application Number:
  US12/573,411
• Publication Number:
  US 20100196482A1
• Time in Patent Office: 974 Days
• Field of Search: None
• US Class Current: 536/24.5
• CPC Class Codes: A61K 47/6907 the form being a microemulsion, nanoemulsion or micelle
• CPC Class Codes: A61K 9/1075 Microemulsions or submicron emulsions; Preconcentrates or solids thereof; Micelles, e.g. made of phospholipids or block copolymers A61K9/0026 takes precedence
• CPC Class Codes: A61K 9/5123 Organic compounds, e.g. fats, sugars
• CPC Class Codes: A61K 9/5153 Polyesters, e.g. poly(lactide-co-glycolide)
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00

Abstract

A method for encapsulating nucleic acids, particularly siRNAs, shRNAs, microRNAs, gene therapy plasmids, and other oligonucleotides in biodegradable polymers is disclosed, whereby the nucleic acids are formulated into reverse micelles composed of non-toxic and/or naturally-occurring lipids prior to nanoparticle formation by nanoprecipitation. This method can be coupled to other techniques that improve intracellular drug targeting, ultimately enhancing intracellular delivery of the aforementioned nucleic acids.

Claims

1. Nanoparticles comprising reverse micelles encapsulating a hydrophilic nucleic acid or protein molecule, wherein the reverse micelles are encapsulated within a hydrophobic polymeric matrix.

2. The nanoparticles of claim 1, wherein targeting moieties are attached to the nanoparticle.

3. The nanoparticles of claim 2, wherein the targeting moiety is an aptamer.

4. The nanoparticles of claim 1, wherein the polymeric matrix comprises two or more polymers.

5. The nanoparticles of claim 1, wherein the polymeric matrix comprises a polymer selected from the group consisting of polyethylenes, polycarbonates, polyanhydrides, polyhydroxyacids, polypropylfumerates, polycaprolactones, polyamides, polyacetals, polyethers, polyesters, poly(orthoesters), polycyanoacrylates, polyvinyl alcohols, polyurethanes, polyphosphazenes, polyacrylates, polymethacrylates, polycyanoacrylates, polyureas, polystyrenes, polyamines, and combinations thereof.

6. The nanoparticles of claim 1, wherein the hydrophobic polymer forming the polymeric matrix comprises a polyalkylene glycol.

7. The nanoparticles of claim 1, wherein the polymeric matrix comprises poly(lactide-co-glycolide) (PLGA), polylactide (PLA), polyglycolide (PGA), or a polycaprolactone.

8. The nanoparticles of claim 1, wherein the polymeric matrix comprises a copolymer of two or more polymers.

9. The nanoparticles of claim 1, wherein the polymeric matrix comprises a lipid-terminated polyalkylene glycol and a polyester.

10. The nanoparticles of claim 9, wherein the polymeric matrix comprises lipid-terminated PEG and PLGA.

11. The nanoparticles of claim 10, wherein the lipid is of the Formula V

12. The nanoparticles of claim 11, wherein the lipid is 1,2 distearoyl-sn-glycero-3-phosphoethanolamine (DSPE), and salts thereof.

13. The nanoparticles of claim 1, further comprising therapeutic, prophylactic or diagnostic agent encapsulated within the hydrophobic matrix of the nanoparticle.

14. The nanoparticles of claim 1, wherein the therapeutic agent is an siRNA.

15. The nanoparticles of claim 1, wherein the reverse micelle comprises an amphipathic lipid.

16. The nanoparticles of claim 15, wherein the amphipathic lipid is selected from the group consisting of lecithin, phosphatidylcholine, lipid A, cholesterol, dolichol, shingosine, sphingomyelin, ceramide, cerebroside, sulfatide, glycosylceramide, phytosphingosine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylserine, cardiolipin, phophatidic acid, and lysophophatides.

17. The nanoparticles of claim 16, wherein the therapeutic agent is a nucleic acid, and the ratio of amphipathic lipid to nucleic acid is approximately 33:

1.

18. The nanoparticles of claim 2, wherein the targeting moiety binds prostate specific membrane antigen (“

PSMA”

).

19. The nanoparticles of claim 18, wherein the targeting moiety binds PSMA on cells selected from the group consisting of prostate cancer, non-small cell lung cancer, colorectal carcinoma, and glioblastoma cells.

20. The nanoparticles of claim 1, wherein the therapeutic agent is a nucleic acid.

21. A pharmaceutical composition comprising the nanoparticles of claim 1 and a pharmaceutically acceptable excipient.

22. A method of preparing a nanoparticle of claim 1, the method comprising steps of

providing a hydrophilic therapeutic agent, diagnostic agent or prophylactic agent;

dissolving the agent with an amphipathic lipid in a volatile, water-miscible organic solvent;

forming reverse micelles, wherein the interior of the reverse micelle is hydrophilic and contains the therapeutic agent, diagnostic agent or prophylactic agent, and the exterior of the reverse micelle is hydrophobic;

adding a solution of a hydrophobic polymer to the mixture of reverse micelles;

combining the resulting mixture with a hydrophilic non-solvent that the polymer is not soluble in to form nanoparticle by rapid diffusion of the solvent into the non-solvent and evaporation of the solvent.

23. The nanoparticle formed by the method of claim 22.

24. The nanoparticles of claim 20, wherein the targeting moiety is an aptamer.

25. The nanoparticles of claim 2, wherein the nanoparticle has a cancer targeting moiety bound thereto.