Details for Patent: 5,916,596

Title:	Protein stabilized pharmacologically active agents, methods for the preparation thereof and methods for the use thereof
Abstract:	In accordance with the present invention, there are provided compositions and methods useful for the in vivo delivery of substantially water insoluble pharmacologically active agents (such as the anticancer drug paclitaxel) in which the pharmacologically active agent is delivered in the form of suspended particles coated with protein (which acts as a stabilizing agent). In particular, protein and pharmacologically active agent in a biocompatible dispersing medium are subjected to high shear, in the absence of any conventional surfactants, and also in the absence of any polymeric core material for the particles. The procedure yields particles with a diameter of less than about 1 micron. The use of specific composition and preparation conditions (e.g., addition of a polar solvent to the organic phase), and careful selection of the proper organic phase and phase fraction, enables the reproducible production of unusually small nanoparticles of less than 200 nm diameter, which can be sterile-filtered. The particulate system produced according to the invention can be converted into a redispersible dry powder comprising nanoparticles of water-insoluble drug coated with a protein, and free protein to which molecules of the pharmacological agent are bound. This results in a unique delivery system, in which part of the pharmacologically active agent is readily bioavailable (in the form of molecules bound to the protein), and part of the agent is present within particles without any polymeric matrix therein.
Inventor(s):	Desai; Neil P. (Los Angeles, CA), Tao; Chunlin (Beverly Hills, CA), Yang; Andrew (Rosemead, CA), Louie; Leslie (Montebello, CA), Zheng; Tianli (Culver City, CA), Yao; Zhiwen (Culver City, CA), Soon-Shiong; Patrick (Los Angeles, CA), Magdassi; Shlomo (Jerusalem, IL)
Assignee:	Vivorx Pharmaceuticals, Inc. (Santa Monica, CA)
Filing Date:	Oct 01, 1996
Application Number:	08/720,756
Claims:	1. A method for the preparation of a substantially water insoluble pharmacologically active agent for in vivo delivery, said method comprising: subjecting a mixture comprising: an organic phase containing said pharmacologically active agent dispersed therein, and aqueous medium containing biocompatible polymer, wherein said mixture contains substantially no surfactants, to high shear conditions in a high pressure homogenizer at a pressure in the range of about 3,000 up to 30,000 psi. 2. A method according to claim 1 further comprising removing said organic phase from said mixture. 3. A method according to claim 1 further comprising removing said aqueous phase from said mixture. 4. A method according to claim 1 wherein said substantially water insoluble pharmacologically active agent is selected from a pharmaceutically active agent, a diagnostic agent, or an agent of nutritional value. 5. A method according to claim 4 wherein said pharmaceutically active agent is selected from the group consisting of analgesics/antipyretics, anesthetics, antiasthamatics, antibiotics, antidepressants, antidiabetics, antifungal agents, antihypertensive agents, anti-inflammatories, antineoplastics, antianxiety agents, immunosuppressive agents, antimigraine agents, sedatives/hypnotics, antianginal agents, antipsychotic agents, antimanic agents, antiarrhythmics, antiarthritic agents, antigout agents, anticoagulants, thrombolytic agents, antifibrinolytic agents, hemorheologic agents, antiplatelet agents, anticonvulsants, antiparkinson agents, antihistamines/antipruritics, agents useful for calcium regulation, antibacterial agents, antiviral agents, antimicrobials, anti-infectives, bronchodialators, hormones, hypoglycemic agents, hypolipidemic agents, proteins, nucleic acids, agents useful for erythropoiesis stimulation, antiulcer/antireflux agents, antinauseants/antiemetics, oil-soluble vitamins, as well as mitotane, visadine, halonitrosoureas, anthrocyclines and ellipticine. 6. A method according to claim 4 wherein said pharmaceutically active agent is an antineoplastic selected from adriamycin, cyclophosphamide, actinomycin, bleomycin, duanorubicin, doxorubicin, epirubicin, mitomycin, methotrexate, fluorouracil, carboplatin, carmustine (BCNU), methyl-CCNU, cisplatin, etoposide, interferon, camptothecin and derivatives thereof, phenesterine, paclitaxel and derivatives thereof, taxotere and derivatives thereof, vinblastine, vincristine, tamoxifen, etoposide or piposulfan. 7. A method according to claim 4 wherein said pharmaceutically active agent is an immunosuppressive agent selected from cyclosporine, azathioprine, mizoribine or FK506 (tacrolimus). 8. A method according to claim 4 wherein said diagnostic agent is selected from ultrasound contrast agents, radiocontrast agents, or magnetic contrast agents. 9. A method according to claim 4 wherein said agent of nutritional value is selected from amino acids, sugars, proteins, carbohydrates, fat-soluble vitamins, or fat, or combinations of any two or more thereof. 10. A method according to claim 1 wherein said organic phase has a boiling point of no greater than about 200.degree. C. 11. A method according to claim 10 wherein said organic phase is selected from soybean oil, coconut oil, olive oil, safflower oil, cotton seed oil, sesame oil, orange oil, limonene oil, aliphatic, cycloaliphatic or aromatic hydrocarbons having 4-30 carbon atoms, aliphatic or aromatic alcohols having 2-30 carbon atoms, aliphatic or aromatic esters having 2-30 carbon atoms, alkyl, aryl, or cyclic ethers having 2-30 carbon atoms, alkyl or aryl halides having 1-30 carbon atoms, optionally having more than one halogen substituent, ketones having 3-30 carbon atoms, polyalkylene glycol, or combinations of any two or more thereof. 12. A method according to claim 10 wherein said organic phase comprises a mixture of a substantially water immiscible organic solvent and a water soluble organic solvent. 13. A method according to claim 1 wherein said biocompatible polymer is a naturally occurring polymer, a synthetic polymer, or a combination thereof. 14. A method according to claim 1 wherein said biocompatible polymer is capable of being crosslinked by disulfide bonds. 15. A method according to claim 13 wherein said naturally occurring polymers are selected from proteins, peptides, polynucleic acids, polysaccharides, proteoglycans or lipoproteins. 16. A method according to claim 13 wherein said synthetic polymers are selected from synthetic polyamino acids containing cysteine residues and/or disulfide groups; polyvinyl alcohol modified to contain free sulfhydryl groups and/or disulfide groups; polyhydroxyethyl methacrylate modified to contain free sulfhydryl groups and/or disulfide groups; polyacrylic acid modified to contain free sulfhydryl groups and/or disulfide groups; polyethyloxazoline modified to contain free sulfhydryl groups and/or disulfide groups; polyacrylamide modified to contain free sulfhydryl groups and/or disulfide groups; polyvinyl pyrrolidinone modified to contain free sulfhydryl groups and/or disulfide groups; polyalkylene glycols modified to contain free sulfhydryl groups and/or disulfide groups; polylactides, polyglycolides, polycaprolactones, or copolymers thereof, modified to contain free sulfhydryl groups and/or disulfide groups; as well as mixtures of any two or more thereof. 17. A method according to claim 1 wherein said high shear conditions comprise contacting said organic phase and said aqueous medium in a high pressure homogenizer at a pressure in the range of about 6,000 up to 25,000 psi. 18. A method according to claim 1 wherein said biocompatible polymer is the protein albumin. 19. A method according to claim 1 wherein said aqueous medium is selected from water, buffered aqueous media, saline, buffered saline, solutions of amino acids, solutions of sugars, solutions of vitamins, solutions of carbohydrates, or combinations of any two or more thereof. 20. A method according to claim 1 wherein said high shear conditions produce particles comprising said pharmacologically active agent coated with said biocompatible polymer. 21. A method according to claim 20 wherein said particles have an average diameter of less than 1 micron. 22. A method according to claim 20 wherein said particles have an average diameter of less than 200 nm. 23. A method according to claim 22 wherein said mixture is sterile filtered. 24. A method according to claim 20 wherein said particles are amorphous, crystalline, or a mixture thereof. 25. A method according to claim 24 wherein said particles are substantially amorphous. 26. A method for the preparation of a substantially water insoluble pharmacologically active agent for in vivo delivery in the form of sterile-filterable particles, said method comprising: subjecting a mixture comprising: an organic phase containing said pharmacologically active agent dispersed therein, wherein said organic phase comprises a mixture of a substantially water immiscible organic solvent and a water soluble organic solvent, and aqueous medium containing biocompatible polymer, wherein said mixture contains substantially no surfactants, to high shear conditions in a high pressure homogenizer at a pressure in the range of about 3,000 up to 30,000 psi. 27. A method according to claim 26 further comprising removing said organic phase from said mixture. 28. A method according to claim 26 further comprising filtering said mixture through a 0.22 micron filter. 29. A method according to claim 26 further comprising removing said aqueous phase from said mixture. 30. A method according to claim 26 wherein said high shear conditions produce amorphous particles, crystalline particles, or a mixture thereof. 31. A method according to claim 30 wherein said particles are substantially amorphous.