Preparation and uses of multi-phase microspheres
First Claim
1. A delivery system for a protein, peptide, or drug with biodegradable multi-phase microspheres, said microspheres comprising a protein, peptide, or drug contained within a fixed oil and an essentially water insoluble, biodegradable polymeric matrix comprised of polylactic acid or polylactic glycolic acid wherein the polymeric matrix surrounds the fixed oil of the microsphere and wherein the fixed oil contains the protein, peptide, or drug.
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Abstract
Multi-phase polymeric microspheres containing a molecular compound dispersed in a polymeric matrix are described. Methods for preparing the multi-phase microspheres are also described, which includes a multiple emulsion solvent evaporation technique. Drug loading efficiencies between 80 to 100% were achieved using the described methods. Particular ratios of the W/O emulsion to polymer, and concentration of surfactant and dispersion media (mineral oil) provide highly efficient multi-phase microspheres. In particular embodiments, the multi-phase microspheres feature a high loading efficiency of water-soluble drugs, and also eliminates partitioning of the water soluble agent into the polymer acetonitrile (solvent) phase, thus preventing low encapsulation efficiency. The described multi-phase microspheres possess efficient drug loading, release properties, and drug stability, and also provide a vehicle for long term therapeutic release of a biologically active molecule for therapeutically effective periods of time. Molecular compounds which may be incorporated within the multi-phase microspheres include both water-soluble and water-insoluble drugs, proteins (e.g. TNF), peptides, and chemicals. The molecular compound is protected within an oily droplet, and contact with polymer, surfactant, organic solvents, and other potentially denaturing agents is prevented.
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Citations
62 Claims
- 1. A delivery system for a protein, peptide, or drug with biodegradable multi-phase microspheres, said microspheres comprising a protein, peptide, or drug contained within a fixed oil and an essentially water insoluble, biodegradable polymeric matrix comprised of polylactic acid or polylactic glycolic acid wherein the polymeric matrix surrounds the fixed oil of the microsphere and wherein the fixed oil contains the protein, peptide, or drug.
- 2. A delivery system for a water-soluble protein, peptide, or drug with biodegradable multi-phase microspheres, said microspheres comprising a microemulsion of a water soluble protein, peptide, or drug, a fixed oil and a biodegradable, essentially water insoluble polymeric matrix of polylactic acid or polylactic glycolic acid, said polymeric matrix surrounding the microemulsion of fixed oil and the protein, peptide, or molecular compound.
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3. A delivery system for cytokines with biodegradable multi-phase microspheres, said microspheres comprising a cytokine contained within a fixed oil, and an essentially water insoluble, biodegradable polymeric matrix of polylactic acid or polylactic glycolic acid, wherein the polymeric matrix surrounds the fixed oil and wherein the fixed oil contains the cytokine.
- 4. A delivery system for tumor necrosis factor with biodegradable multi-phase microspheres said microspheres comprising a lyophilized microemulsion of an aqueous solution of tumor necrosis factor in a fixed oil, and an essentially water insoluble, biodegradable polymeric matrix of polylactic acid or polylactic glycolic acid, wherein the polymeric matrix surrounds said microemulsion of tumor necrosis factor and fixed oil.
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19. A method for providing sustained release of a protein, peptide, or drug in an animal comprising:
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preparing a formulation of microspheres, said microspheres containing the protein, peptide, or drug in a fixed oil, and a biodegradable essentially water insoluble polymeric matrix of polylactic acid or polylactic glycolic acid; and administering an amount of the formulation effective to provide sustained release of the protein, peptide, or drug in the animal for a prescribed period of time, wherein the polymeric matrix surrounds the fixed oil and the fixed oil contains the protein, peptide, or drug. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26, 27, 28)
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29. A method for preparing multi-phase microspheres containing a protein, peptide, or dug comprising:
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mixing an aqueous solution of the protein, peptide, or drug with a fixed oil to form a W/O microemulsion; mixing polylactic acid or polylactic glycolic acid and a polymer solvent together to form a polymer solution; dispersing the microemulsion into the polymer solution to form a W/O/"O" emulsion; mixing the W/O/"O" emulsion together in a dispersion oil which is incompatible with the polymer solvent to form a multiple emulsion; agitating and removing the solvent from the multiple emulsion to form hardened microspheres; and washing and drying the hardened microspheres to form multi-phase microspheres containing the water-soluble protein, peptide, or drug. - View Dependent Claims (30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 43, 44)
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45. A method for preparing microspheres containing a water-soluble drug comprising:
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preparing a first mixture of a water-soluble drug in water, gelatin and Tween 80 to form an aqueous phase; preparing a second mixture of an amount of aluminum stearate and a volume of a fixed oil to produce a 2% w/w aluminum stearate and about 5% w/w Span 80 oil phase; combining the first mixture with the second mixture to form a coarse W/O emulsion; processing the coarse W/O emulsion into a fine W/O microemulsion; preparing a third mixture of polylactic acid or polylactic glycolic acid and a solvent; combining a quantity of the fine W/O microemulsion with the third mixture to form a W/O/"O" emulsion; preparing a fourth mixture of an amount of Span 80 and an oil incompatible with the polymer solvent; pouring the W/O/"O" emulsion into the fourth mixture to form a multiple emulsion; agitating and evaporating the polymer solvent from the multiple emulsion to form hardened microspheres; separating the hardened microspheres from the mixture; and washing and drying the hardened microspheres to form multi-phase microspheres containing a water-soluble drug. - View Dependent Claims (46, 47, 48, 49, 50, 51, 52, 53)
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54. A multi-phase microsphere for the delivery of a peptide, protein, or drug comprising a biodegradable essentially water insoluble polymeric matrix of polylactic acid or polylactic glycolic acid surrounding a protein, peptide, or drug contained within a fixed oil, said microsphere prepared by a process of:
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preparing a first mixture of a water-soluble protein, peptide, or dug in water, gelatin and Tween 80 to form an aqueous base; preparing a second mixture of an amount of aluminum stearate and a volume of a fixed oil to produce a 2% w/w aluminum stearate and about 5% w/w span 80 oil phase; combining the first mixture with the second mixture to form a coarse W/O emulsion; processing the coarse W/O emulsion into a fine W/O micro emulsion; preparing a third mixture of a biodegradable essentially water-insoluble polymer polylactic acid of polylactic glycolic acid and a solvent; combining a quantity of the fine W/O micro emulsion with the third mixture to form a W/O/"O" emulsion; preparing a fourth mixture of an amount of span 80 and an oil incompatible with the polymer solvent; pouring the W/O/"O" emulsion into the fourth mixture to form a multiple emulsion; evaporating the solvent from the multiple emulsion to form hardened microspheres; separating the hardened microspheres from the mixture; and washing and drying the hardened microspheres to form multi-phase microspheres containing a water-soluble protein, peptide, or drug. - View Dependent Claims (55, 56, 57)
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- 58. A biodegradable polymeric microsphere comprising an essentially water insoluble poly (d,l-lactic acid) or poly (d,l-lactic) co-glycolic acid polymeric matrix surrounding a protein-containing fixed oil droplet.
Specification