# US 8,771,728 B2 · Stable lipid-comprising drug delivery complexes and methods for their production > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,771,728 B2 - Document ID: US8771728B2 - Status: Granted - Kind: B2 - Application number: 13/712,804 - Filed: 2012-12-12 - Published: 2013-10-24 - Granted: 2014-07-08 - Earliest claimed: 1995-01-23 - Assignees: University of Pittsburgh—Of the Commonwealth System of Higher Education - Applicants: University of Pittsburgh—Of the Commonwealth System of Higher Education - Inventors: Leaf Huang; Xiang Gao; Frank L. Sorgi - Web page: https://patentgrep.com/patent/US8771728B2 ## CPC - A61K 47/543: {Lipids, e.g. triglycerides; Polyamines, e.g. spermine or spermidine} - A61K 9/1272: comprising non-phosphatidyl surfactants as bilayer-forming substances, e.g. cationic lipids or non-phosphatidyl liposomes coated or grafted with polymers (lipids as modifying agents {A61K47/543}) - A61K 47/645: {Polycationic or polyanionic oligopeptides, polypeptides or polyamino acids, e.g. polylysine, polyarginine, polyglutamic acid or peptide TAT} - C12N 15/88: using microencapsulation, e.g. using {amphiphile} liposome vesicle - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) ## Abstract Novel stable, concentrated, biologically active and ready-to-use lipid-comprising drug delivery complexes and methods for their production are described. The biological activity of the complexes produced are comparable to the formulations prepared according to the prior art admixture method and upon purification, the complexes produced by the method of this invention are 50 to 500 fold more concentrated than the complexes formed by admixture. The method described herein provides for the large scale production of lipid-comprising drug delivery systems useful for gene therapy and other applications. ## Claims ### Claim 1 A noncovalent nucleic acid/lipid/polycation complex having a net positive charge at pH 6.0-8.0 comprising at least one cationic lipid and a polycation in a ratio of nucleic acid to lipid to polycation which results in the production of said complex, said polycation being selected from the group consisting of polyarginine, polyornithine, polybrene (hexadimethrine bromide), histone, cationic dendrimer, spermine, spermidine, protamine, and synthetic peptides derived from SV40 large T antigen and comprising a nuclear localization sequence, wherein said polycation does not comprise a targeting factor directed to a particular tissue or cell type; and, wherein the complex is formed by adding a nucleic acid to a mixture comprising the at least one cationic lipid and the polycation. ### Claim 2 (depends on 1) The complex of claim 1, wherein the polycation has a molecular weight of 300 to 200,000 Daltons. ### Claim 3 (depends on 1) The complex of claim 1, wherein the polycation is a histone. ### Claim 4 (depends on 1) The complex of claim 1, wherein the polycation is a peptide derived from SV40 large T antigen. ### Claim 5 (depends on 4) The complex of claim 4, wherein said peptide comprises a nuclear localization sequence. ### Claim 6 (depends on 1) The complex of claim 1, wherein the polycation comprises spermine or spermidine. ### Claim 7 (depends on 1) The complex of claim 1, wherein the polycation is a protamine. ### Claim 8 (depends on 7) The complex of claim 7, wherein the protamine is selected from the group consisting of protamine free base, protamine phosphate, protamine chloride, protamine sulfate from salmon, and protamine sulfate from herring. ### Claim 9 (depends on 1) The complex of claim 1, wherein the ratio of lipid to nucleic acid ranges from about 0.1 nmol to 200 nmol lipid per 1 μg nucleic acid. ### Claim 10 (depends on 1) The complex of claim 1, wherein the ratio of lipid to nucleic acid ranges from about 1 nmol to about 25 nmol lipid per 1 μg nucleic acid. ### Claim 11 (depends on 1) The complex of claim 1, wherein the polycation:nucleic acid ratio is about 0.01 μg to about 100 μg polycation to 1 μg nucleic acid. ### Claim 12 A method for producing a noncovalent nucleic acid/lipid/polycation complex having a net positive charge at pH 6.0-8.0, the method comprising, mixing said nucleic acid with at least one cationic lipid and polycation in a ratio of nucleic acid to lipid to polycation which results in the production of said complex, said polycation being selected from the group consisting of polyarginine, polyornithine, polybrene (hexadimethrine bromide), histone, cationic dendrimer, spermine, spermidine, protamine, and synthetic peptides derived from a nuclear localization sequence of SV40 large T antigen, wherein said polycation does not comprise a targeting factor directed to a particular tissue or cell type; and, wherein said nucleic acid is added to a mixture of the at least one cationic lipid and the polycation. ### Claim 13 (depends on 12) The method of claim 12, wherein the polycation has a molecular weight of 300 to 200,000 Daltons. ### Claim 14 (depends on 12) The method of claim 12, wherein the polycation comprises a histone, spermine, spermidine, or a peptide derived from SV40 large T antigen. ### Claim 15 (depends on 12) The method of claim 12, wherein the polycation is a protamine. ### Claim 16 (depends on 15) The method of claim 15, wherein the protamine is selected from the group consisting of protamine free base, protamine phosphate, protamine chloride, protamine sulfate from salmon, and protamine sulfate from herring. ### Claim 17 (depends on 1) A method for delivering a nucleic acid to cells comprising contacting the cells with the noncovalent nucleic acid/lipid/polycation complex of claim 1.