WO2006093390A1 - Nonporous microspheres including drug and manufacturing method thereof - Google Patents

Nonporous microspheres including drug and manufacturing method thereof

Info

Publication number
WO2006093390A1
WO2006093390A1 PCT/KR2006/000740 KR2006000740W WO2006093390A1 WO 2006093390 A1 WO2006093390 A1 WO 2006093390A1 KR 2006000740 W KR2006000740 W KR 2006000740W WO 2006093390 A1 WO2006093390 A1 WO 2006093390A1
Authority
WO
WIPO (PCT)
Prior art keywords
drug
microsphere
polymer
vaccine
poly
Prior art date
Application number
PCT/KR2006/000740
Other languages
French (fr)
Inventor
Hong-Kee Kim
Tae-Gwan Park
Hyun-Jung Chung
Original Assignee
Korea Advanced Institute Of Science And Technology
Daewoong Pharmaceutical Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Korea Advanced Institute Of Science And Technology, Daewoong Pharmaceutical Co., Ltd. filed Critical Korea Advanced Institute Of Science And Technology
Publication of WO2006093390A1 publication Critical patent/WO2006093390A1/en

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/30Macromolecular organic or inorganic compounds, e.g. inorganic polyphosphates
    • A61K47/34Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyesters, polyamino acids, polysiloxanes, polyphosphazines, copolymers of polyalkylene glycol or poloxamers
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00Medicinal preparations characterised by special physical form
    • A61K9/14Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
    • A61K9/16Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
    • A61K9/1605Excipients; Inactive ingredients
    • A61K9/1629Organic macromolecular compounds
    • A61K9/1641Organic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyethylene glycol, poloxamers
    • A61K9/1647Polyesters, e.g. poly(lactide-co-glycolide)
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/30Macromolecular organic or inorganic compounds, e.g. inorganic polyphosphates
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00Medicinal preparations characterised by special physical form
    • A61K9/14Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
    • A61K9/16Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
    • A61K9/1682Processes
    • A61K9/1694Processes resulting in granules or microspheres of the matrix type containing more than 5% of excipient

Definitions

  • the present invention relates to nonporous polymer microspheres including a drug and a manufacturing method thereof, and a method for using nonporous polymer microspheres including a drug as a drug releasing formulation for sustained release of a drug in a human body, and more particularly, to nonporous microspheres of which multipores are sealed after a drug being introduced into the microspheres through pores, and a manufacturing method thereof, and a use of the nonporous polymer microsphere including a drug as a drug releasing formulation for sustained release of a drug in a human body.
  • a technology for controlling a drug release using a biodegradable polymer microsphere is focused on applying it into a physiologically active material having low molecular weight.
  • peptide or protein with a high moleculer weights have been developed as a new therapeutic agents, and there have been various attempts to continuously release by introducing a drug into a polymer microsphere.
  • polyesters are poly-L-lactic acid, poly- glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, polyhy- droxybutylate and polyhydroxyvalerate.
  • a major reason causing this unstability is the existence of an interface between an aqueous solution and an organic solvent in the W/O/W process, and it has been known that the existence of the interface is one of the major reasons to denaturize a drug like protein, condense it and get rid of a pharmacological activity.
  • a formulating method for preventing forming of an aqueous solution/organic solvent interface in a process for introducing a protein drug in a microsphere For example, a protein is made into a microparticles to be directly dispersed in an organic solvent where a polymer is melted and to introduce it into a polymer microsphere.
  • a microsphere which continuously releases a drug in the human body is manufactured by a method comprising manufacturing a porous microsphere having a plurality of pores using a biodegradable polymer, introducing a soluble drug into a microsphers through the pores and closing the pores of the microsphere using an organic solvent to develop a microsphere where an release rate of a drug is controlled. It is confirmed that the microsphere continuously releases a drug with a constant concentration and the present invention is completed.
  • An object of the present invention is to provide a nonporous polymer microsphere including a drug.
  • Another object of the present invention is to provide a method for manufacturing a nonporous polymer microsphere including a drug.
  • Another object of the present invention is to provide a method for using the nonporous polymer microsphere including a drug as a drug releasing formulations for continuously releasing a drug in a human body.
  • a nonporous polymer microsphere including a drug has a structure formed by a process comprising the steps of introducing a drug into a microsphere comprising a biodegradable polyester polymer through pores formed a microsphere, dissolving the polymer around the pores and closing the pores by fusing the polymers to continuously release the drug.
  • a biodegradable polyester polymer one of the major components of a nonporous polymer microsphere including a drug in the present invention can use anything unharmful to a human body and gradually dissolved to release a drug in the human body.
  • the biodegradable polyester polymer used in the present invention does not require for particular limits.
  • the biodegradable polyester series polymer is one or a mixture of more than two selected from the group consisting of poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, poly- hydroxybutylate and polyhydroxyvalerate.
  • a drug introduced through the pores into a biodegradable polyester polymer does not require for particular limits, in other words, can be selected from the group consisting of a human growth hormone, a human epidermal growth factor, FITC-Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony-stimulating Factor), erythropoietin, BCG vaccine, hepatitis B vaccine, influenza vaccine, Japanese encephalitis vaccine, influenza virus vaccine, measles biovirus vaccine, pneumonia coccus vaccine, typhoid vaccine, chicken pox virus, parotitis biodegradable virus vaccine, anti-hCG antibody, anti ⁇ - hCG antibody, anti ⁇ -hCG antibody, IgG antibody, anti LH monoclone antibody, H.pylori antibody combined protein, purified OKT3 monoclone antibody, insulin, calcitonin, adre
  • the present invention includes a method for manufacturing a nonporous polymer microsphere comprising: (1) dissolving a biodegradable polyester polymer and a hydrophilic polymer for pore-forming into an organic solvent;
  • a process for closing the pores in the process (4) can be obtained by contacting an organic solvent at a steam state to a porous microshere.
  • FIG. 1 shows an embodiment of a manufacturing process of a nonporous polymer microsphere including a protein as a drug into a porous polymer microsphere.
  • a nonporous polymer microsphere including a drug not only can continuously release a drug but also prevent forming of an interface between an organic solvent and aqueous solution in a manufacturing process and also prevent occurring harsh conditions denaturizing a protein drug.
  • FIG. 1 is a mimetic diagram showing a method for manufacturing a microsphere for continuously releasing a drug of the present invention using a porous microsphere.
  • Fig. 2 is a mimetic diagram of a fluidized bed reactor (FBR) being used to close pores of a porous microsphere.
  • FBR fluidized bed reactor
  • Fig. 3 A is a photograph of a surface and a cross-sectional scanning microscope of a porous biodegradable microsphere including a drug manufactured in accordance with an embodiment of the present invention.
  • Fig. 3B is a photograph of a surface and a cross-sectional scanning microscope of a biodegradable microsphere including a drug having closed pores of the microsphere (Fig. 3A) in accordance with an embodiment of the present invention.
  • Figs. 4 to 7 are graphs showing a behavior of a continuous releasing of a microsphere including a drug manufactured in an embodiment of the present invention.
  • the biodegradable polyester series polymer forms a basis of a nonporous polymer microsphere including a drug, which is introduced via pores of the biodegradable polyester polymer.
  • the biodegradable polyester polymer may include any polymers unharmful to a human body and gradually dissolved to release a drug in the human body.
  • the biodegradable polyester series polymer is one or a mixture of more than two selected from the group consisting of poly-L-lactic acid, poly-glycolic acid, poly- D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, polyhydroxybutylate and polyhydroxy valerate with an average molecular weight of 500-100,000.
  • a biodegradable polyester polymer according to the present invention if a copolymer consisting of a lactic acid and a glycolic acid is used, a copolymer with a molar ratio of lactic acid to glycolic acid in the range of 10:90 ⁇ 90: 10 can be used.
  • a biodegradable polyester polymer in the present invention may be poly-
  • the hydrophilic polymer for pore-forming is not limited to any specific polymers provided that it can be melted into an organic solvent along with a polyester polymer, being released into an aqueous solution when contacting an aqueous solution and providing a polymer microsphere with pores by separation.
  • a hydrophilic polymer for pore-forming can be selected from a polymer with a hy- drophilic/hydrophobic average value (HLB) of 10-40 and an average molecular weight of 500-100,000, more particularly, may be one or a mixture of more than two selected from the group consisting of a Pluronic being a block copolymer with polyethylene glycol and polypropylene glycol, polyethylene glycol, polyethylene glycol derivatives, dextran or Bovine Serum Albumin (BSA).
  • HLB hy- drophilic/hydrophobic average value
  • BSA Bovine Serum Albumin
  • Pluronic uses Pluronic L35, Pluronic F127, Pluronic F77, Pluronic F88 or Pluronic F38 with a HLB value in 19-31, and more preferably, Pluronic fl27, Pluronic F77 and Pluronic F88 with an average molecular weight of 8000-12,000 and a HLB value in 22-28.
  • Polyethylene glycol may be one with an average molecular weight of 500-100,000, and more particularly, one with an average molecular weight of 10,000-50,000.
  • Polyethylene glycol derivatives may be one with an average molecular weight of
  • methoxy polyethylene glycol mPEG
  • polyethylene glycol butylether methoxy polyethylene amine
  • methoxy polyoxyethylene carboxylic acid methoxy polyethylene glycol butylether
  • methoxy polyethylene amine methoxy polyoxyethylene carboxylic acid
  • polyoxyethylene bisamine methoxy polyoxyethylene carboxylic acid
  • polyoxyethylene bisamine methoxy polyoxyethylene carboxylic acid
  • polyoxyethylene bisamine polyoxyethylene bisacetic acid
  • polyoxyethylene bis (6-aminohexyl 6-aminohexyl
  • the hydrophilic polymers can be suitably selected in consideration of HLB values, a molecular weight and kinds or amounts of a biodegradable polyester polymer.
  • an organic solvents include, but are not limited to the solvents having a solubility with respect to a biodegradable polyester polymer and a hydrophilic polymer for pore-forming, for example, one selected from methylene chloride, chloroform, acetone, dimethylsulfoxide, dimethylformamide, N- methyl pyrrolidone, dioxane, tetrahydrofuran, ethylacetate, methylethylketone or ace- tonitrile.
  • methylene chloride or chloroform having an excellent solubility with respect to a biodegradable polyester polymer and a hydrophilic polymer for pore- forming, being easily removed by evaporation as a volatile organic solvent and forming a porous polymer microsphere is used as a solvent and more particularly, methylene chloride is used as a solvent.
  • a biodegradable polyester series polymer and a polymer for pore-forming are melted into an organic solvent and an aqueous solution is emulsified to form a microsphere. Therefore, it is possible to form a porous microsphere of an object by properly controlling a ratio of polyester polymer playing a role as a frame including pores and a hydrophilic polymer playing a role for directly forming pores.
  • a composition ratio of a polyester polymer to a hydrophilic polymer for pore-forming which are melted into an organic solvent is 10:90-90:10 in a weight ratio, and more preferably, 20:80-30:70.
  • a biodegradable polyester polymer and a hydrophilic polymer for pore-forming are melted into an organic solvent and an aqueous solution is emulsified to form a microsphere.
  • the aqueous solution may include a hydrophilic surfactant so that the hydophilic polymer for pore-forming is released to the aqueous solution.
  • the hydrophilic surfactant include, but are not limited to those having a high reactivity with the hydrophilic polymer for pore-forming, thus letting out a hydrophile polymer for pore forming from a polyester polymer to an aqueous solution, for example, one or a mixture of more than two selected from the group consisting of Tween, Triton, Breeze, polyvinylpyrrolidone and polyvinyl alcohol.
  • the polyvinyl alcohols include, but are not limited to those with a molecular weight of 13,000-23,000 in 0.1 ⁇ 5wt% and more particularly, one with a molecular weight of 13,000-23,000 in 0.5 wt%.
  • a polymer for pore-forming is let out onto an aqueous solution from the organic solvent to form pores on a microsphere.
  • the polyester polymer is hardened to form a frame of the microsphere.
  • a volume ratio of an organic solvent is 1-20% and a volume ratio of an aqueous solution is 80-99%, and more particularly, a volume ratio of an organic solvent is 3-10% and a volume ratio of an aqueous solution is 90-97%.
  • the porous mircosphere is freeze-dried by a centrifugal separation to obtain a porous biodegradable polymer microsphere.
  • the porous biodegradable polymer microsphere is obtained by performing a centrifugal separation at 500 ⁇ 10,000rpm for 3 ⁇ 30minutes, freezing at 0°C ⁇ 70°C, drying at 4 ⁇ 35°C.
  • a drug is introduced into a porous polymer microsphere through pores obtained in the process (3) and the pores are closed to obtain a nonporous microsphere including a drug.
  • a drug can include a vaccine, a hormone medicine and other hydrophilic therapeutic agents requiring for administrating for a long period, for example, those selected from the group consisting of a human growth hormone, a human epidermal growth factor, FITC-Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony- stimulating Factor), erythropoietin, vaccine, antibody, insulin, calcitonin, adrenocorticotropic hormone ACTH, glucagons, somatostatin, somatotropin, somatomedin, parathyroid hormone, hypothalamus secretion material, thyroid hormone, prolactin, endorphin, vascular endothelial growth factor (VEGF), enkephalin, vasopressin, nerve growth factor, non- naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase
  • G-CSF
  • a method for introducing a drug to be continuously released through pores of a biodegradable porous microsphere may include any methods used in introducing a conventional drug at a microsphere.
  • a drug to be introduced into a microsphere is manufactured in a solution state and the microsphere is dispersed into the drug solution.
  • a drug can be introduced or in another method, a drug element having the size less than the diameter of a pore of a porous microsphere is directly mixed with a porous microsphere.
  • a drug is introduced into a porous microsphere and the pores of the microsphere are closed to obtain a nonporous microsphere including a drug. After a drug is introduced, a nonporous microsphere is obtained by the processes for partially dissolving the polymers distributed around the pores and fusing them.
  • the organic solvents which can be vapourized include, but are not limited to those selected from the group consisting of ethanol, methanol, methylene chloride, chloroform, acetone, dioxane, tetrahydrofuran, ethylacetate or acetonitrile. It is preferable to use ethanol which is the least harmful to a human body and has a slight solubility with respect to a polyester polymer to be easily transformed into a steam state.
  • the organic solvent at a steam state can be contacted with a biodegradable porous microsphere in a fluidized bed reactor (FBR) with reference to Fig. 2.
  • FBR fluidized bed reactor
  • a pore of a porous microsphere may be closed with the following method using a fluidized bed reactor and an organic solvent.
  • the fluidized bed reactor uniformly floats a biodegradable porous microsphere including a drug into an air.
  • An organic solvent capable of melting a polyester polymer is sprayed in a steam state. This state is maintained for a proper time so that a porous microsphere becomes a nonporous microsphere and the microsphere maintains the shape of each object to close pores, therefore a nonporous microsphere can be obtained.
  • FIG. 2 The configuration of the fluidized bed reactor (FBR) is briefly shown in Fig. 2.
  • a nitrogen gas is sprayed into an organic solvent so that a composed organic solvent steam needs to be sprayed to a floating porous microsphere under a proper pressure.
  • the organic solvent steam swells a polymer of a microsphere to become a rubbery and sticky state.
  • the organic solvent at a steam state partially melts a porous microsphere polymer and fuses the polymers around the pores of porous microsphere to gradually decrease pore size and finally close it.
  • the present invention includes a method for using a nonporous polymer microsphere including a drug as a drug releasing formulation for sustained release in the human body.
  • Pluronic F127 of 0.7g and poly-D, L-lactic acid-co-glycolic acid (PLGA) of 0.3g with a ratio of lactic acid to glycolic acid of 75:25 and a molecular weight of 10,000 are melted into methylene chloride of 3ml.
  • Fig. 3A shows a surface and a cross-section of the porous microsphere manufactured in the above method taken by a scanning microscope.
  • An average diameter of a porous microsphere is 52.1+9.9D, and an average diameter of a pore is 5.5+1.0D.
  • the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human growth hormone is melted with the concentration of 20mg/ml and stirred at a low speed of lOrpm for two hours so that the human growth hormone solution is infiltrated into the pore structure of the microsphere.
  • the microsphere is centrifuged at 2000rpm for 10 minutes and freeze-dried at -20°C to manufacture a porous polymer microsphere including a human growth hormone.
  • a fluidized bed reactor (FBR) shown in Fig. 2 is used to close pores of a porous polymer microsphere including the manufactured human growth hormone.
  • the fluidized bed reactor uses a glass with an internal diameter of 24mm and a height of 660mm and has a glass filter at the bottom so that a nitrogen gas for floating a porous microsphere is uniformly sprayed from the bottom.
  • the nitrogen gas is sprayed into an ethanol to become a steam state and the nitrogen gas saturated with the ethanol at the steam state is atomized through a silicon nozzle positioned on a glass filter of a reactor.
  • the reactor is maintained to have 25°C by a wafer jacket surrounding the reactor.
  • the arrow in Fig. 2 means that a nitrogen gas is flowed in.
  • a porous polymer microsphere of 40mg including a drug is put in the reactor and a nitrogen gas for floating is sprayed under the pressure of 0.04kgf/cm . Ethanol steam is atomized to a microsphere floating in the air under the same pressure. The nonporous polymer microsphere of which pores are closed is collected by the treatment for 10 minutes and cleaned with a distilled water and dried.
  • Fig. 3B shows a picture of a surface and a cross-section of a biodegradable polymer microsphere of which pores are closed taken by a scanning microsphere.
  • An average diameter of the microsphere of which pores are closed is 15.6+5.4D and it is known that the pores are completely closed.
  • a nonporous polymer microsphere including a human growth hormone is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human growth hormone is melted with the concentration of 50mg/ml.
  • a porous polymer microsphere including a drug of 20mg and a nonporous polymer microsphere including a drug of 20mg manufactured in the embodiment 2 are dispersed into a physiological saline solution of 1.5ml including sodium azide of 0.01%(w/v) and Tween 20 of 0.02% (w/v) and preserved in the culture medium of a temperature at 37°C.
  • a porous polymer microsphere and a nonporous polymer microsphere including a drug are centrifuged once per two days and an upper liquid is collected to measure the amount of the released protein by a Microbicinchoninic acid method.
  • a human growth hormone remaining in the microsphere is extracted since the drug release period.
  • a sodium hydroxide solution of 0.5ml with the con- centration of 0.5N is added and preserved in the culture medium for one day to melt PLGA by a hydrolysis.
  • the total amount of a protein extracted by the method and an released protein is obtained to measure the total amount of a human growth hormone included in a microsphere.
  • the amount of the included human growth hormone can be controlled by controlling the concentration of a human growth hormone solution where a porous microsphere is soaked.
  • a human growth hormone with a weight ratio of 3.5+0. l(w/w)% is included at a porous microsphere state, and with a weight ratio of 3.1 ⁇ 0.1(w/w)% is included after pores are closed.
  • a human growth hormone with a weight ratio of 11.4 ⁇ 0.5(w/w)% is included at a porous microsphere state, and with a weight ratio of 7.0 ⁇ 0.3(w/w)% is included after pores are closed.
  • the amount of effective drug included in a microsphere can be easily controlled by changing the concentration of a drug solution.
  • Fig. 4 shows that a human growth hormone is released from a biodegradable polymer microsphere including the manufactured drug in accordance with a change of the time.
  • Fig. 4A is a graph showing the amount of a human growth hormone released from each polymer microsphere including a human growth hormone of 5mg/ml into a porous polymer microsphere and a nonporous polymer microsphere in accordance with a change of the time.
  • FIG. 4B is a graph showing the amount of a human growth hormone released from each polymer microsphere including a human growth hormone of 20mg/ml into a porous polymer microsphere and a nonporous polymer microsphere in accordance with a change of the time.
  • FIG. 4 Oshows an release amount of a human growth hormone included in a porous polymer microsphere manufactured in the embodiment 1 in accordance with time, and # shows an release amount of a human growth hormone included in a nonporous polymer microsphere manufactured in the embodiment 2 in accordance with time.
  • a nonporous polymer microsphere including FITC-dextran is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where the FITC-dextran is melted with the concentration of 20mg/ml.
  • a nonporous polymer microsphere including rhEGF is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human epidermal growth factor rhEGF is melted with the concentration of 20mg/ml.
  • a nonporous polymer microsphere including DNA is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where DNA is melted with the concentration of 100D/ml.

Abstract

The present invention relates to a nonporous polymer microsphere including a drug and a method thereof, and a method for using the nonporous polymer microsphere including a drug as a drug releasing formulation for continuously releasing the drug in the human body.

Description

Description
NONPOROUS MICROSPHERES INCLUDING DRUG AND MANUFACTURING METHOD THEREOF
Technical Field
[1] The present invention relates to nonporous polymer microspheres including a drug and a manufacturing method thereof, and a method for using nonporous polymer microspheres including a drug as a drug releasing formulation for sustained release of a drug in a human body, and more particularly, to nonporous microspheres of which multipores are sealed after a drug being introduced into the microspheres through pores, and a manufacturing method thereof, and a use of the nonporous polymer microsphere including a drug as a drug releasing formulation for sustained release of a drug in a human body. Background Art
[2] Recently, formulations for injectable and oral administration which are currently used have a difficulty in maintaining a drug concentration in a human body by one medication.
[3] Accordingly, in order to maintain a drug concentration of the human body for a long time, researches on medicines for sustained(continuously) release of a drug in a human body by introducing a drug in a biodegradable polymer microsphere and gradually dissolving the polymer microsphere in the human body have been carried out. [K. Fu, R. Harrell, K. Zinski, C. Um, A, Jaklenec, J. Frazier, N. Lotan, P. Burke A. M. Klibanov R. Langer, J. Pharm. ScL 92 (2003) 1582-1591; R. Langer, Ace. Chem. Res. 33 (2000) 94-101; W. R. Gombotz and D.K. Pettit, Bioconj. Chem. 6 (1995) 332-351, R. Langer and N.A. Peppas, Biomaterials, 2 (1981) 210-214].
[4] If a biodegradable polymer mircosphere system has been introduced, the polymer microsphere is gradually degraded in a human body after being injected to be changed into a low molecular- weight material unharmful to the human body. Accordingly, this system is advantageous in that no surgical removing processes of a polymer microsphere are required after a drug is released for a certain period, therefore researches on applying this into medical supplies continue.
[5] A technology for controlling a drug release using a biodegradable polymer microsphere is focused on applying it into a physiologically active material having low molecular weight. However, peptide or protein with a high moleculer weights have been developed as a new therapeutic agents, and there have been various attempts to continuously release by introducing a drug into a polymer microsphere.
[6] Recently, various kinds of polymer microspheres have been developed. For example, it is already confirmed that an aliphatic polyester is biocompatible and obtained approval of U.S. Food and Drug Association was obtained, and is widely used as a carrier for delivering a drug and a suture yarn for an operation.
[7] The representative examples of aliphatic polyesters are poly-L-lactic acid, poly- glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, polyhy- droxybutylate and polyhydroxyvalerate. [L. B. Peppas, Inter. J. ofPharm. 116 (1995)
1-9].
[8] One of the most widely researched methods for introducing a water soluble drug into a microsphere formed of an aliphatic polyester is a double emulsion method being Water-in-Oil-in-Water (W/O/W).
[9] This method is advantageous in that most of water soluble drugs are included in a microsphere. However, there are harsh conditions in a sealing process, it is disadvantageous in affecting the stability of a drug.
[10] Especially, in case of a huge drug like peptide or protein, the problems related to the unstability of a drug such as a covalent/non-covalent condensation, a nonspecific absorption and a denaturation occur in the course of introducing a drug into a microsphere.
[11] A major reason causing this unstability is the existence of an interface between an aqueous solution and an organic solvent in the W/O/W process, and it has been known that the existence of the interface is one of the major reasons to denaturize a drug like protein, condense it and get rid of a pharmacological activity. [H. K. Kim, T. G. Park, Biotech. Bioeng. 65 (1999) 659-667; H. Sah, J. Pharm. ScL 88 (1999) 1320-1325; C. Perez-Rodriguez, N. Montano, K. Gonzalez, K. Griebenow, J. Control. ReI. 89 (2003) 71-85].
[12] An initial burst of a drug and a problem that the drug cannot be released in a microsphere to the outside occur due to the stability of a drug, thus, it is difficult to control a drug to be released at a constant speed for a certain period. For example, in case of a protein drug like a Bovine Serum Albumin or lysozyme, the final released amount is almost 50% after a lot of drugs are released at an initial stage. [G. Crotts, and T.G. Park, J. Control. ReI. 44 (1997) 123-134; N.B. Leonard, L.H. Michael, M.M. Lee, J. Pharm. ScL 84 707-712]. In addition, in a case that a recombinant human growth hormone is introduced into an aliphatic polyester microsphere, 30-50% of the protein drug is initially released but 40-60% reportedly cannot be released and remain in the microsphere. [C. Yan, et al. J. Control. ReI. 32 (1994) 231-241].
[13] A lot of attempts for solving the problems related to the stability of a drug have been made in a process for introducing the drug in a microsphere in various viewspoints. Especially, a research for solving the protein denaturization problem at an interface between an aqueous solution and an organic solvent draws attention in a process for introducing a protein drug in a polymer microsphere.
[14]
[15] As one approach of this research, an approaching method for increasing a protein stability at an interface between an aqueous solution and an organic solvent by adding a stabilizer is researched. [O.L. Johnson et al. Pharm Res. 14 (1997) 730-735; M.A. Tracy, Biotech. Prog. 14 (1998) 108-115]. For example, Tween20, Tween40, Tween80, polyethylene glycol (PEG), Carboxymethyl cellulose, Mannitol, Trehalos, Dextran 70, Gelatine and so forth decrease the denaturization of a human growth hormone at an interface between an aqueous solution and an organic solvent. There are examples that Mannitol, Gelantine, Trehalose, Mannitol/Trehalose and Carboxymethyl Cellulose and so forth were applied in manufacturing a polymer microsphere including a human growth hormone. [J.L. Cleland and A.J.S. Jones, Pharm. Res. 13 (1996) 1464-1475].
[16] As another approaching method, there is a formulating method for preventing forming of an aqueous solution/organic solvent interface in a process for introducing a protein drug in a microsphere. For example, a protein is made into a microparticles to be directly dispersed in an organic solvent where a polymer is melted and to introduce it into a polymer microsphere. [T. Morita, Y. Sakamura, Y. Horikiri, T. Suzuki, H. Yoshino, J. Control. ReI. 69 (2000) 435-444]
[17] There is another method for dispersing a human growth hormone to a solvent along with a polymer to spray at a low temperature and extract the solvent. [J.L. Cleland, O.L. Johnson, S. Putney, A.J.S. Jones, Adv. Drug Deliv. Rev. 28 (1997) 71-84; O.L. Johnson et al. Pharm. Res. 14 (1997) 730-735]
[18] These methods are approaching methods for solving the problems by removing an occurrence of an aqueous solution and an organic solvent being the reasons of problems.
[19] However, there is a problem that a lot of drugs remain in a microsphere after an initial burst and an release completion when polymer microsphere containing a protein is manufactured using these approaches. For example, when polymer microsphere containing a human growth hormone is manufactured using Gelatine, Mannitol/ Carboxymethyl Cellulose and Carboxymethyl Cellulose as a stabilizer, the ratio of a monomer among in the human growth hormone is just 66-70%.
[20] As above, a lot of portions of a technology for applying a general drug, especially a protein drug to manufacture a microsphere continuously releasing a drug in a human body still remain unsolved. Disclosure of Invention Technical Problem
[21] As a result that the inventors have researched to continuously develop microspheres for refraining an initial burst of a drug in a human body with maintaining the stability of a drug including a polymer microsphere for a couple of years, a new polymer microsphere distinguishable from the existing method for manufacturing a microsphere and a method thereof have been established.
[22] In the present invention, a microsphere which continuously releases a drug in the human body is manufactured by a method comprising manufacturing a porous microsphere having a plurality of pores using a biodegradable polymer, introducing a soluble drug into a microsphers through the pores and closing the pores of the microsphere using an organic solvent to develop a microsphere where an release rate of a drug is controlled. It is confirmed that the microsphere continuously releases a drug with a constant concentration and the present invention is completed.
[23] An object of the present invention is to provide a nonporous polymer microsphere including a drug.
[24] Another object of the present invention is to provide a method for manufacturing a nonporous polymer microsphere including a drug.
[25] Another object of the present invention is to provide a method for using the nonporous polymer microsphere including a drug as a drug releasing formulations for continuously releasing a drug in a human body. Technical Solution
[26] In order to achieve the objects of the present invention, a nonporous polymer microsphere including a drug has a structure formed by a process comprising the steps of introducing a drug into a microsphere comprising a biodegradable polyester polymer through pores formed a microsphere, dissolving the polymer around the pores and closing the pores by fusing the polymers to continuously release the drug.
[27] A biodegradable polyester polymer, one of the major components of a nonporous polymer microsphere including a drug in the present invention can use anything unharmful to a human body and gradually dissolved to release a drug in the human body.
[28] The biodegradable polyester polymer used in the present invention does not require for particular limits. In other words, the biodegradable polyester series polymer is one or a mixture of more than two selected from the group consisting of poly-L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, poly- hydroxybutylate and polyhydroxyvalerate.
[29] In the present invention, a drug introduced through the pores into a biodegradable polyester polymer does not require for particular limits, in other words, can be selected from the group consisting of a human growth hormone, a human epidermal growth factor, FITC-Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony-stimulating Factor), erythropoietin, BCG vaccine, hepatitis B vaccine, influenza vaccine, Japanese encephalitis vaccine, influenza virus vaccine, measles biovirus vaccine, pneumonia coccus vaccine, typhoid vaccine, chicken pox virus, parotitis biodegradable virus vaccine, anti-hCG antibody, anti α- hCG antibody, anti β-hCG antibody, IgG antibody, anti LH monoclone antibody, H.pylori antibody combined protein, purified OKT3 monoclone antibody, insulin, calcitonin, adrenocorticotropic hormone, glucagons, somatostation, somatotropin, somatomedin, parathyroid hormone, thyroid stimulating hormone, thyroid hormone, progesterone stimulating hormone, follicle stimulating hormone, luteinizing hormone, prolactin, endorphin, vascular endothelial growth factor, enkephalin, oxytocin, vasopressin, nerve growth factor, non-naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase, trypsin, chymotrypsin, pepsin, DNA, siRNA and oligo DNA.
[30] In the meantime, the present invention includes a method for manufacturing a nonporous polymer microsphere comprising: (1) dissolving a biodegradable polyester polymer and a hydrophilic polymer for pore-forming into an organic solvent;
[31] (2) dispersing and emulsifying the solution including the polyester polymer and a hydrophilic polymer for pore-forming into an aqueous solution;
[32] (3) removing an organic solvent from a solution including a polyester polymer after the emulsification to obtain a porous polymer microsphere having a plurality of pores; and
[33] (4) introducing a drug into a porous polymer mircrosphere, dissolving and fusing the polymers around the pores to close the pores.
[34] A process for closing the pores in the process (4) can be obtained by contacting an organic solvent at a steam state to a porous microshere.
[35] Fig. 1 shows an embodiment of a manufacturing process of a nonporous polymer microsphere including a protein as a drug into a porous polymer microsphere.
[36]
Advantageous Effects
[37] As shown in the embodiments of the present invention, a nonporous polymer microsphere including a drug not only can continuously release a drug but also prevent forming of an interface between an organic solvent and aqueous solution in a manufacturing process and also prevent occurring harsh conditions denaturizing a protein drug. Brief Description of the Drawings
[38] The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:
[39] Fig. 1 is a mimetic diagram showing a method for manufacturing a microsphere for continuously releasing a drug of the present invention using a porous microsphere.
[40] Fig. 2 is a mimetic diagram of a fluidized bed reactor (FBR) being used to close pores of a porous microsphere.
[41] Fig. 3 A is a photograph of a surface and a cross-sectional scanning microscope of a porous biodegradable microsphere including a drug manufactured in accordance with an embodiment of the present invention.
[42] Fig. 3B is a photograph of a surface and a cross-sectional scanning microscope of a biodegradable microsphere including a drug having closed pores of the microsphere (Fig. 3A) in accordance with an embodiment of the present invention.
[43] Figs. 4 to 7 are graphs showing a behavior of a continuous releasing of a microsphere including a drug manufactured in an embodiment of the present invention.
[44]
Best Mode for Carrying Out the Invention
[45] The methods for manufacturing a nonporous polymer microsphere including a drug now will be described in detail with reference to the following steps hereinafter.
[46] 1. Dissolving a biodegradable polyester series polymer and a hydrophile polymer for pore-forming into an organic solvent.
[47] In the present invention, the biodegradable polyester series polymer forms a basis of a nonporous polymer microsphere including a drug, which is introduced via pores of the biodegradable polyester polymer. In the present invention, the biodegradable polyester polymer may include any polymers unharmful to a human body and gradually dissolved to release a drug in the human body.
[48] The biodegradable polyester series polymer is one or a mixture of more than two selected from the group consisting of poly-L-lactic acid, poly-glycolic acid, poly- D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, polycaprolactone, polyvalerolactone, polyhydroxybutylate and polyhydroxy valerate with an average molecular weight of 500-100,000.
[49] In a biodegradable polyester polymer according to the present invention, if a copolymer consisting of a lactic acid and a glycolic acid is used, a copolymer with a molar ratio of lactic acid to glycolic acid in the range of 10:90 ~ 90: 10 can be used.
[50] Preferably, a biodegradable polyester polymer in the present invention may be poly-
D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid or poly-D, L-lactic acid-co-glycolic acid (PLGA), more preferably, poly-D, L-lactic acid-co-glycolic acid (PLGA) with a molecular weight of 5000-50,000, the most preferably, poly-D, L- lactic acid-co-glycolic acid (PLGA) with a molar ratio of 75:25 and a molecular weight of 8000-12,000.
[51] The hydrophilic polymer for pore-forming is not limited to any specific polymers provided that it can be melted into an organic solvent along with a polyester polymer, being released into an aqueous solution when contacting an aqueous solution and providing a polymer microsphere with pores by separation.
[52] A hydrophilic polymer for pore-forming can be selected from a polymer with a hy- drophilic/hydrophobic average value (HLB) of 10-40 and an average molecular weight of 500-100,000, more particularly, may be one or a mixture of more than two selected from the group consisting of a Pluronic being a block copolymer with polyethylene glycol and polypropylene glycol, polyethylene glycol, polyethylene glycol derivatives, dextran or Bovine Serum Albumin (BSA).
[53] Preferably, Pluronic uses Pluronic L35, Pluronic F127, Pluronic F77, Pluronic F88 or Pluronic F38 with a HLB value in 19-31, and more preferably, Pluronic fl27, Pluronic F77 and Pluronic F88 with an average molecular weight of 8000-12,000 and a HLB value in 22-28.
[54] Polyethylene glycol may be one with an average molecular weight of 500-100,000, and more particularly, one with an average molecular weight of 10,000-50,000.
[55] Polyethylene glycol derivatives may be one with an average molecular weight of
500-100,000, and more particularly, one selected from the group consisting of methoxy polyethylene glycol (mPEG), polyethylene glycol butylether, methoxy polyethylene amine, methoxy polyoxyethylene carboxylic acid, polyoxyethylene bisamine, polyoxyethylene bisacetic acid and polyoxyethylene bis (6-aminohexyl).
[56] The hydrophilic polymers can be suitably selected in consideration of HLB values, a molecular weight and kinds or amounts of a biodegradable polyester polymer.
[57] In the process (1) of the present invention, an organic solvents include, but are not limited to the solvents having a solubility with respect to a biodegradable polyester polymer and a hydrophilic polymer for pore-forming, for example, one selected from methylene chloride, chloroform, acetone, dimethylsulfoxide, dimethylformamide, N- methyl pyrrolidone, dioxane, tetrahydrofuran, ethylacetate, methylethylketone or ace- tonitrile. Preferably, methylene chloride or chloroform having an excellent solubility with respect to a biodegradable polyester polymer and a hydrophilic polymer for pore- forming, being easily removed by evaporation as a volatile organic solvent and forming a porous polymer microsphere is used as a solvent and more particularly, methylene chloride is used as a solvent.
[58] A biodegradable polyester series polymer and a polymer for pore-forming are melted into an organic solvent and an aqueous solution is emulsified to form a microsphere. Therefore, it is possible to form a porous microsphere of an object by properly controlling a ratio of polyester polymer playing a role as a frame including pores and a hydrophilic polymer playing a role for directly forming pores.
[59] Preferbly, a composition ratio of a polyester polymer to a hydrophilic polymer for pore-forming which are melted into an organic solvent is 10:90-90:10 in a weight ratio, and more preferably, 20:80-30:70.
[60] 2. Dispersing and emulsifying a solution including the polyester polymer and a hydrophilic polymer for pore-forming into an aqueous solution.
[61] A biodegradable polyester polymer and a hydrophilic polymer for pore-forming are melted into an organic solvent and an aqueous solution is emulsified to form a microsphere.
[62] When a solution including a polyester polymer and a hydrophile polymer for pore- forming are dispersed and emulsified into an aqueous solution, the aqueous solution may include a hydrophilic surfactant so that the hydophilic polymer for pore-forming is released to the aqueous solution.
[63] The hydrophilic surfactant include, but are not limited to those having a high reactivity with the hydrophilic polymer for pore-forming, thus letting out a hydrophile polymer for pore forming from a polyester polymer to an aqueous solution, for example, one or a mixture of more than two selected from the group consisting of Tween, Triton, Breeze, polyvinylpyrrolidone and polyvinyl alcohol.
[64] If a polyvinyl alcohol is used as a hydrophilic polymer, the polyvinyl alcohols include, but are not limited to those with a molecular weight of 13,000-23,000 in 0.1~5wt% and more particularly, one with a molecular weight of 13,000-23,000 in 0.5 wt%.
[65] A polymer for pore-forming is let out onto an aqueous solution from the organic solvent to form pores on a microsphere. As an organic solvent is removed, the polyester polymer is hardened to form a frame of the microsphere. Thus, as an escaping speed of a polymer for pore-forming and a removing speed of an organic solvent in the process (3) are different depending on a ratio of an organic solvent and an aqueous solution, the structure of the obtained microsphere can be changed.
[66] In consideration of the above mentioned situation, when it comes to a volume ratio of an organic solvent to an aqueous solution, it is preferable to adopt the formulation conditions that a volume ratio of an organic solvent is 1-20% and a volume ratio of an aqueous solution is 80-99%, and more particularly, a volume ratio of an organic solvent is 3-10% and a volume ratio of an aqueous solution is 90-97%.
[67]
[68] 3. Removing an organic solvent from a solution including a polyester polymer after the emulsification to obtain a porous polymer microsphere having a plurality of pores.
[69] As a biodegradable polyester series polymer and a hydrophilic polymer for pore- forming are melted into an organic solvent by the processes (1) and (2), and the organic solvent is evaporated and removed by dispersing/emulsifying a hydrophilic surfactant with a proper volume ratio into an aqueous solution, a hydrophilic polymer for pore forming is let out to the aqueous solution and a polyester polymer is hardened to form a porous microsphere.
[70] The porous mircosphere is freeze-dried by a centrifugal separation to obtain a porous biodegradable polymer microsphere. The porous biodegradable polymer microsphere is obtained by performing a centrifugal separation at 500~10,000rpm for 3~30minutes, freezing at 0°C~70°C, drying at 4~35°C.
[71]
[72] 4. Introducing a drug into a porous polymer mircrosphere, contacting an organic solvent at a steam state and closing the pores of a porous polymer microsphere to obtain a nonporous microsphere including a drug.
[73] A drug is introduced into a porous polymer microsphere through pores obtained in the process (3) and the pores are closed to obtain a nonporous microsphere including a drug.
[74] At this time, a drug can include a vaccine, a hormone medicine and other hydrophilic therapeutic agents requiring for administrating for a long period, for example, those selected from the group consisting of a human growth hormone, a human epidermal growth factor, FITC-Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony- stimulating Factor), erythropoietin, vaccine, antibody, insulin, calcitonin, adrenocorticotropic hormone ACTH, glucagons, somatostatin, somatotropin, somatomedin, parathyroid hormone, hypothalamus secretion material, thyroid hormone, prolactin, endorphin, vascular endothelial growth factor (VEGF), enkephalin, vasopressin, nerve growth factor, non- naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase, trypsin, chymotrypsin, pepsin, DNA, siRNA and oligo DNA.
[75] A method for introducing a drug to be continuously released through pores of a biodegradable porous microsphere may include any methods used in introducing a conventional drug at a microsphere. For example, in a method, a drug to be introduced into a microsphere is manufactured in a solution state and the microsphere is dispersed into the drug solution. As a solution is introduced into the microsphere via the pores, a drug can be introduced or in another method, a drug element having the size less than the diameter of a pore of a porous microsphere is directly mixed with a porous microsphere. These methods for introducing a drug are suitable for manufacturing the present invention. [76] A drug is introduced into a porous microsphere and the pores of the microsphere are closed to obtain a nonporous microsphere including a drug. After a drug is introduced, a nonporous microsphere is obtained by the processes for partially dissolving the polymers distributed around the pores and fusing them.
[77] The process of fusing polymers including the steps of vapourizing an organic solvent and reacting with a microsphere manufactured in accordance with the present invention is shown in a preferred embodiment of the present invention. These processes partially dissolve and fuse the polymers around the pores to gradually decrease the pore size, and finally close the pores of the microsphere.
[78] The organic solvents which can be vapourized include, but are not limited to those selected from the group consisting of ethanol, methanol, methylene chloride, chloroform, acetone, dioxane, tetrahydrofuran, ethylacetate or acetonitrile. It is preferable to use ethanol which is the least harmful to a human body and has a slight solubility with respect to a polyester polymer to be easily transformed into a steam state.
[79] The organic solvent at a steam state can be contacted with a biodegradable porous microsphere in a fluidized bed reactor (FBR) with reference to Fig. 2.
[80] A pore of a porous microsphere may be closed with the following method using a fluidized bed reactor and an organic solvent.
[81] The fluidized bed reactor (FBR) uniformly floats a biodegradable porous microsphere including a drug into an air. An organic solvent capable of melting a polyester polymer is sprayed in a steam state. This state is maintained for a proper time so that a porous microsphere becomes a nonporous microsphere and the microsphere maintains the shape of each object to close pores, therefore a nonporous microsphere can be obtained.
[82]
[83] The configuration of the fluidized bed reactor (FBR) is briefly shown in Fig. 2. In order to float a porous polymer microsphere in a fluidized bed reactor (FBR), an applied nitrogen gas pressure needs to be controlled minutely. In addition, a nitrogen gas is sprayed into an organic solvent so that a composed organic solvent steam needs to be sprayed to a floating porous microsphere under a proper pressure. The organic solvent steam swells a polymer of a microsphere to become a rubbery and sticky state. The organic solvent at a steam state partially melts a porous microsphere polymer and fuses the polymers around the pores of porous microsphere to gradually decrease pore size and finally close it.
[84] In the meantime, the present invention includes a method for using a nonporous polymer microsphere including a drug as a drug releasing formulation for sustained release in the human body. [85] The present invention now will be described more concretely by the embodiments.
These embodiments are used for describing the present invention more concretely, and it is apparent that a scope of the present invention is not limited to the embodiments to those skilled in the art.
[86]
[87] <Embodiment 1> Manufacturing a porous biodegradable polymer microsphere.
[88] Pluronic F127 of 0.7g and poly-D, L-lactic acid-co-glycolic acid (PLGA) of 0.3g with a ratio of lactic acid to glycolic acid of 75:25 and a molecular weight of 10,000 are melted into methylene chloride of 3ml.
[89] An organic solvent where Pluronic F127 and PLGA are melted is put in an aqueous solution of 7ml containing polyvinyl alcohol (of which 88% is hydrolyzed and having a molecular weight of 13,000-23,000) of 0.5%(w/v), and is emulsified using a ho- mogenizer at l,500rpm for 90seconds. The emulsified solution of which an organic solvent is removed is stirred for four hours to harden PLGA in a hood at the conditions of normal temperature and normal pressure. As PLGA starts being hardened and a porous biodegradable polymer microsphere is formed, the stirring is stopped. The PLGA is centrifuged at 2000rpm for 10 minutes and cleaned with a distilled water three times and freeze-dried at -20°C to manufacture a porous biodegradable polymer microsphere.
[90] Fig. 3A shows a surface and a cross-section of the porous microsphere manufactured in the above method taken by a scanning microscope. An average diameter of a porous microsphere is 52.1+9.9D, and an average diameter of a pore is 5.5+1.0D.
[91] <Embodiment 2> Manufacturing a nonporous polymer microsphere including
HGH.
[92] The PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human growth hormone is melted with the concentration of 20mg/ml and stirred at a low speed of lOrpm for two hours so that the human growth hormone solution is infiltrated into the pore structure of the microsphere. The microsphere is centrifuged at 2000rpm for 10 minutes and freeze-dried at -20°C to manufacture a porous polymer microsphere including a human growth hormone.
[93] A fluidized bed reactor (FBR) shown in Fig. 2 is used to close pores of a porous polymer microsphere including the manufactured human growth hormone.
[94] The fluidized bed reactor (FBR) uses a glass with an internal diameter of 24mm and a height of 660mm and has a glass filter at the bottom so that a nitrogen gas for floating a porous microsphere is uniformly sprayed from the bottom. In addition, the nitrogen gas is sprayed into an ethanol to become a steam state and the nitrogen gas saturated with the ethanol at the steam state is atomized through a silicon nozzle positioned on a glass filter of a reactor. The reactor is maintained to have 25°C by a wafer jacket surrounding the reactor. The arrow in Fig. 2 means that a nitrogen gas is flowed in.
[95] A porous polymer microsphere of 40mg including a drug is put in the reactor and a nitrogen gas for floating is sprayed under the pressure of 0.04kgf/cm . Ethanol steam is atomized to a microsphere floating in the air under the same pressure. The nonporous polymer microsphere of which pores are closed is collected by the treatment for 10 minutes and cleaned with a distilled water and dried.
[96] Fig. 3B shows a picture of a surface and a cross-section of a biodegradable polymer microsphere of which pores are closed taken by a scanning microsphere. An average diameter of the microsphere of which pores are closed is 15.6+5.4D and it is known that the pores are completely closed.
[97]
[98] <Embodiment 3> Manufacturing a nonporous polymer microsphere including HGH
(2).
[99] A nonporous polymer microsphere including a human growth hormone is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human growth hormone is melted with the concentration of 50mg/ml.
[100]
[101] <Experiment 1> Releasing a protein drug of a nonporous polymer microsphere.
[102] In order to confirm if a human growth hormone is continuously controlled to release from a biodegradable polymer microsphere, an amount of release is measured in the in vitro condition as follows.
[103] By closing pores of a nonporous polymer microsphere manufactured in the embodiment 1 and of a porous polymer microsphere manufactured in the embodiment 2, a porous polymer microsphere including a drug of 20mg and a nonporous polymer microsphere including a drug of 20mg manufactured in the embodiment 2 are dispersed into a physiological saline solution of 1.5ml including sodium azide of 0.01%(w/v) and Tween 20 of 0.02% (w/v) and preserved in the culture medium of a temperature at 37°C.
[104] A porous polymer microsphere and a nonporous polymer microsphere including a drug are centrifuged once per two days and an upper liquid is collected to measure the amount of the released protein by a Microbicinchoninic acid method.
[105] In order to determine a weight ratio of a protein included in a microsphere, a human growth hormone remaining in the microsphere is extracted since the drug release period. To make it possible, a sodium hydroxide solution of 0.5ml with the con- centration of 0.5N is added and preserved in the culture medium for one day to melt PLGA by a hydrolysis. The total amount of a protein extracted by the method and an released protein is obtained to measure the total amount of a human growth hormone included in a microsphere.
[106] The amount of the included human growth hormone can be controlled by controlling the concentration of a human growth hormone solution where a porous microsphere is soaked.
[107] In a case of a microsphere soaked in the human growth hormone solution of
5mg/ml, a human growth hormone with a weight ratio of 3.5+0. l(w/w)% is included at a porous microsphere state, and with a weight ratio of 3.1±0.1(w/w)% is included after pores are closed.
[108] In a case of a microsphere soaked in the human growth hormone solution of
20mg/ml, a human growth hormone with a weight ratio of 11.4±0.5(w/w)% is included at a porous microsphere state, and with a weight ratio of 7.0±0.3(w/w)% is included after pores are closed. Thus, the amount of effective drug included in a microsphere can be easily controlled by changing the concentration of a drug solution.
[109] Fig. 4 shows that a human growth hormone is released from a biodegradable polymer microsphere including the manufactured drug in accordance with a change of the time.
[110] Fig. 4A is a graph showing the amount of a human growth hormone released from each polymer microsphere including a human growth hormone of 5mg/ml into a porous polymer microsphere and a nonporous polymer microsphere in accordance with a change of the time.
[I l l] Fig. 4B is a graph showing the amount of a human growth hormone released from each polymer microsphere including a human growth hormone of 20mg/ml into a porous polymer microsphere and a nonporous polymer microsphere in accordance with a change of the time.
[112] In Fig. 4, Oshows an release amount of a human growth hormone included in a porous polymer microsphere manufactured in the embodiment 1 in accordance with time, and # shows an release amount of a human growth hormone included in a nonporous polymer microsphere manufactured in the embodiment 2 in accordance with time.
[113] As shown Fig. 4, all amount of human growth hormone included in a porous microsphere is released, but its releasing rate is very fast to make the continuity of the release slight. To the contrary, a human growth hormone included in a microsphere where pores are closed is continuously released throughout 40 days.
[114] This tendency is maintained in spite of the amount of a human growth hormone included in a microsphere. In a case of a microsphere including a human growth hormone with a weight ratio of 3.1±0.1(w/w)%, the initial release with a weight ratio of 6.2+1. l(w/w)% continues for 40 days and 80% is released as shown in Fig. 4A.
[115] Moreover, in a case of a microsphere including a human growth hormone with a weight ratio of 7.0±0.3(w/w)%, the initial release with a weight ratio of 31.3±0.4(w/w)% continues for 40 days and 80% is released as shown in Fig. 4B. Therefore, it has been confirmed that a microsphere manufactured in the embodiment 2 has a very excellent shape in continuously releasing a drug.
[116]
[117] <Embodiment 4> Manufacturing a nonporous polymer microsphere including
FITC-dextran.
[118] A nonporous polymer microsphere including FITC-dextran is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where the FITC-dextran is melted with the concentration of 20mg/ml.
[119]
[120] <Embodiment 5> Manufacturing a nonporous polymer microsphere including rhEGF.
[121] A nonporous polymer microsphere including rhEGF is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where a human epidermal growth factor rhEGF is melted with the concentration of 20mg/ml.
[122]
[123] <Embodiment 6> Manufacturing a nonporous polymer microsphere including
DNA.
[124] A nonporous polymer microsphere including DNA is manufactured with the same method as the embodiment 2 except that the PLGA microsphere of 400mg manufactured in the embodiment 1 is dispersed into a physiological saline solution where DNA is melted with the concentration of 100D/ml.
[125]
[126] <Experiment 2> Releasing protein drug in a nonporous polymer microsphere (2).
[127] In order to confirm if a drug is continuously released from a biodegradable polymer microsphere including a drug manufactured in the embodiments 4 through 6, a release is measured by the same process as the experiment 1, and their results are shown in Figs. 5 through 7.
[128] As shown in FIGs. 5 through 7, it has been confirmed that a microsphere manufactured in the embodiments has a very excellent shape in continuously releasing a drug.
[129]

Claims

Claims
[1] A nonporous polymer microsphere including a drug, having a structure formed by a process comprising the steps of introducing a drug into a microsphere ccomprising a biodegradable polyester polymer through pores on the microsphere, dissolving the polymers around the pores and closing the pores by fusing the polymers to continuously release the drug.
[2] The nonporous polymer microsphere including a drug of the claim 1, wherein the biodegradable polyester polymer is selected from a group consisting of poly- L-lactic acid, poly-glycolic acid, poly-D-lactic acid-co-glycolic acid, poly- L-lactic acid-co-glycolic acid, poly-D, L-lactic acid-co-glycolic acid, poly- caprolactone, polyvalerolactone, polyhydroxybutylate and polyhydroxyvalerate.
[3] The nonporous polymer microsphere including a drug of the claim 1, wherein the drug is selected from the group consisting of a human growth hormone, a human epidermal growth factor, FITC-Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony- stimulating Factor), erythropoietin, BCG vaccine, hepatitis B vaccine, influenza vaccine, Japanese encephalitis vaccine, influenza virus vaccine, measles biovirus vaccine, pneumonia coccus vaccine, typhoid vaccine, chicken pox virus, parotitis biodegradable virus vaccine, anti-hCG antibody, anti α-hCG antibody, anti β- hCG antibody, IgG antibody, anti LH monoclone antibody, H.pylori antibody combined protein, purified OKT3 monoclone antibody, insulin, calcitonin, adrenocorticotropic hormone, glucagons, somatostation, somatotropin, somatomedin, parathyroid hormone, thyroid stimulating hormone, thyroid hormone, progesterone stimulating hormone, follicle stimulating hormone, luteinizing hormone, prolactin, endorphin, vascular endothelial growth factor, enkephalin, oxytocin, vasopressin, nerve growth factor, non-naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase, trypsin, chy- motrypsin, pepsin, DNA, siRNA and oligo DNA.
[4] A method for manufacturing a nonporous polymer microsphere capable of continuously releasing a drug comprising: dissolving a biodegradable polyester polymer and a hydrophilic polymer for pore-forming into an organic solvent; dispersing and emulsifying a solution including the polyester polymer and a hydrophilic polymer for pore-forming into an aqueous solution; removing an organic solvent from a solution including a polyester polymer after the emulsification to obtain a porous polymer microsphere having a plurality of pores; and introducing a drug into a porous polymer mircrosphere, dissolving and fusing the polymers around the pores to the pores.
[5] The method of the claim 4, wherein the process for closing pores include a process for contacting an organic solvent at a steam state to a porous microshere.
[6] The method of the claim 5, wherein the biodegradable polyester polymer is selected from a group consisting of poly-L-lactic acid, poly-glycolic acid, poly- D-lactic acid-co-glycolic acid, poly-L-lactic acid-co-glycolic acid, poly-D, L- lactic acid-co-glycolic acid, polycaprolactone, poly valerolac tone, polyhydrox- ybutylate and polyhydroxyvalerate.
[7] The method of the claim 5, wherein the hydrophilic polymer for forming a pore is selected from the group consisting of Pluronic L35, Pluronic F127, Pluronic F77, Pluronic F88, polyethylene glycol (PEG), methoxy polyethylene glycol butylether, methoxy polyethylene amine, methoxy polyoxyethylene carboxylic acid, polyoxyethylene bisamine, polyoxyethylene bisacetic acid, polyoxyethylene bis (6-aminohexyl), dextran and bovine serum albumin (BSA).
[8] The method of the claim 5, wherein the organic solvent is selected from the group consisting of methylene chloride, chloroform, acetone, dimethylsulfoxide, dimethylformamide, N-methyl pyrrolidone, dioxane, tetrahydrofuran, ethylaceta te, methylethylketone or acetonitrile.
[9] The method of the claim 5, wherein the aqueous solution further comprises a hydrophilic surfactant.
[10] The method of the claim 9, wherein the hydrohilic surfactant is selected from the group consisting of Tween, Triton, Breeze, polyvinylpyrrolidon and polyvinyl alcohol.
[11] The method of the claim 5, wherein the organic solvent used at a steam state is selected from the group consisting of ethanol, methanol, methylene chloride, chloroform, acetone, dioxane, tetrahydrofuran, ethylacetate or acetonitrile.
[12] The method of the claim 5, wherein the organic solvent at a steam state contacts the biodegradable porous microsphere in a fluidized bed reactor.
[13] The method of the claim 5, wherein the drug is selected from the group consisting of a human growth hormone, a human epidermal growthfactor, FITC- Dextran, G-CSF (Granulocyte Colony- stimulating Factor), GM-CSF (Granulocyte-Macrophage Colony-stimulating Factor), erythropoietin, BCG vaccine, hepatitis B vaccine, influenza vaccine, Japanese encephalitis vaccine, influenza virus vaccine, measles biovirus vaccine, pneumonia coccus vaccine, typhoid vaccine, chicken pox virus, parotitis biodegradable virus vaccine, anti- hCG antibody, anti α-hCG antibody, anti β-hCG antibody, IgG antibody, anti LH monoclone antibody, H.pylori antibody combined protein, purified OKT3 monoclone antibody, insulin, calcitonin, adrenocorticotropic hormone, glucagons, somatostation, somatotropin, somatomedin, parathyroid hormone, thyroid stimulating hormone, thyroid hormone, progesterone stimulating hormone, follicle stimulating hormone, luteinizing hormone, prolactin, endorphin, vascular endothelial growth factor, enkephalin, oxytocin, vasopressin, nerve growth factor, non-naturally occurring opioid, superoxide dismutase, interferon, asparaginase, arginase, trypsin, chymotrypsin, pepsin, DNA, siRNA and oligo DNA.
[14] The method of the claim 1 to 4, wherein a nonporous polymer microsphere is used as a drug releasing formulation for continuously releasing a drug in a human body.
PCT/KR2006/000740 2005-03-03 2006-03-03 Nonporous microspheres including drug and manufacturing method thereof WO2006093390A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2005-0017704 2005-03-03
KR1020050017704A KR100622996B1 (en) 2005-03-03 2005-03-03 Nonporous microspheres including drug and manufacturing method thereof

Publications (1)

Publication Number Publication Date
WO2006093390A1 true WO2006093390A1 (en) 2006-09-08

Family

ID=36941404

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2006/000740 WO2006093390A1 (en) 2005-03-03 2006-03-03 Nonporous microspheres including drug and manufacturing method thereof

Country Status (2)

Country Link
KR (1) KR100622996B1 (en)
WO (1) WO2006093390A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010004299A2 (en) * 2008-07-11 2010-01-14 Critical Pharmaceuticals Limited Composition
WO2012161492A1 (en) * 2011-05-20 2012-11-29 Sk Chemicals Co., Ltd. Method for preparing microparticles with reduced initial burst and microparticles prepared thereby
CN103860392A (en) * 2014-01-27 2014-06-18 广东职业技术学院 Hydrophobic solid microspheres containing epidermal growth factors and preparation method and application of microspheres
US9226900B2 (en) 2008-07-11 2016-01-05 Critical Pharmaceuticals Limited Process for preparing microparticles
GB2613656A (en) * 2021-12-13 2023-06-14 Pharmathen Sa Sustained release injectable pharmaceutical formulation of levothyroxine and process for preparation thereof

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20120048811A (en) * 2010-11-08 2012-05-16 에스케이케미칼주식회사 Pharmaceutical composition containing microspheres loaded with anastrozole as an active ingredient
KR101785515B1 (en) * 2010-11-08 2017-10-16 에스케이케미칼주식회사 Pharmaceutical composition containing microspheres loaded with olanzapine as an active ingredient
KR101620511B1 (en) * 2014-09-04 2016-05-12 가톨릭대학교 산학협력단 thermo-sensitive biodegradable hydrogel
KR20190122368A (en) * 2018-04-20 2019-10-30 한국세라믹기술원 Injectable thermosponge nanoparticle based hydrogel and its use

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5330768A (en) * 1991-07-05 1994-07-19 Massachusetts Institute Of Technology Controlled drug delivery using polymer/pluronic blends
WO1998032427A1 (en) * 1997-01-27 1998-07-30 United States Government As Represented By The Secretary Of The Army Therapeutic treatment and prevention of infections with a bioactive material encapsulated within a biodegradable-biocompatible polymeric matrix
US20040105878A1 (en) * 1999-12-15 2004-06-03 Schwendeman Steven P. Methods for stabilizing biologically active agents encapsulated in biodegradable controlled-release polymers

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MY107937A (en) 1990-02-13 1996-06-29 Takeda Chemical Industries Ltd Prolonged release microcapsules.
KR100321854B1 (en) * 1998-12-30 2002-08-28 동국제약 주식회사 Long-term sustained-release microspheres containing luteinizing hormone releasing hormone homologues and a method of producing the same
AR023940A1 (en) 2000-05-03 2002-09-04 Eriochem Sa PROCEDURE FOR THE PRODUCTION OF PROLONGED WATERPROOF PEPTIDE MICROCAPSULES IN WATER

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5330768A (en) * 1991-07-05 1994-07-19 Massachusetts Institute Of Technology Controlled drug delivery using polymer/pluronic blends
WO1998032427A1 (en) * 1997-01-27 1998-07-30 United States Government As Represented By The Secretary Of The Army Therapeutic treatment and prevention of infections with a bioactive material encapsulated within a biodegradable-biocompatible polymeric matrix
US20040105878A1 (en) * 1999-12-15 2004-06-03 Schwendeman Steven P. Methods for stabilizing biologically active agents encapsulated in biodegradable controlled-release polymers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PEREZ ET AL.: "Poly(lactic acid)-poly(ethylene glycol) nanoparticles as new carriers for the delivery of plasmid DNA", J. CONTROL. RELEASE, vol. 75, 2001, pages 211 - 224, XP004254417, DOI: doi:10.1016/S0168-3659(01)00397-2 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010004299A2 (en) * 2008-07-11 2010-01-14 Critical Pharmaceuticals Limited Composition
WO2010004299A3 (en) * 2008-07-11 2010-11-11 Critical Pharmaceuticals Limited Pharmaceutical compositions of somatotrophic hormones
GB2474001A (en) * 2008-07-11 2011-03-30 Critical Pharmaceuticals Ltd Pharmaceutical compositions of somatotrophic hormones
US9226900B2 (en) 2008-07-11 2016-01-05 Critical Pharmaceuticals Limited Process for preparing microparticles
WO2012161492A1 (en) * 2011-05-20 2012-11-29 Sk Chemicals Co., Ltd. Method for preparing microparticles with reduced initial burst and microparticles prepared thereby
CN103826615A (en) * 2011-05-20 2014-05-28 Sk化学株式会社 Method for preparing microparticles with reduced initial burst and microparticles prepared thereby
KR101481859B1 (en) * 2011-05-20 2015-01-14 에스케이케미칼주식회사 Method for preparing microparticles with reduced initial drug release and microparticles prepare thereby
CN103860392A (en) * 2014-01-27 2014-06-18 广东职业技术学院 Hydrophobic solid microspheres containing epidermal growth factors and preparation method and application of microspheres
GB2613656A (en) * 2021-12-13 2023-06-14 Pharmathen Sa Sustained release injectable pharmaceutical formulation of levothyroxine and process for preparation thereof

Also Published As

Publication number Publication date
KR20060098548A (en) 2006-09-19
KR100622996B1 (en) 2006-09-14

Similar Documents

Publication Publication Date Title
WO2006093390A1 (en) Nonporous microspheres including drug and manufacturing method thereof
Sinha et al. Biodegradable microspheres for protein delivery
US9877922B2 (en) Process of preparing microspheres for sustained release having improved dispersibility and syringeability
Ye et al. Issues in long-term protein delivery using biodegradable microparticles
CA2453507C (en) A controlled release biodegradable gel matrix
AU2008241699B2 (en) A biodegradable microsphere composition suitable for the controlled release of glucose controlling peptide and formulation thereof
KR100303681B1 (en) Sustained release preparation of water soluble peptide
DK1742616T3 (en) The microsphere-discharge-system for the prolonged delivery and methods of making and using the same
AU2002320441A1 (en) A controlled release biodegradable gel matrix
WO2000066085A1 (en) A bioactive agent delivering system comprised of microparticles within a biodegradable to improve release profiles
WO2002053136A1 (en) Sustained release preparations
US20190133951A1 (en) Preparation method of sustained-release microparticles
WO2017186076A1 (en) Solid dispersion, preparation method for same, and applications thereof
Saez et al. Microspheres as delivery systems for the controlled release of peptides and proteins
Clarke et al. Influence of Formulation Variables on the Morphology of Biodegradable Micropartieles Prepared by Spray Drying
US20220133630A1 (en) Preparation method of sustained-release microparticles
KR100381382B1 (en) Biodegradable Microparticles for the Controlled Release of Drugs and Process for Preparing the Same
US20210154147A1 (en) Preparation method of sustained-release microparticles
US20160324798A1 (en) Polymer-based compositions for extended release of proteins
Kwon Thermosensitive biodegradable hydrogels for the delivery of therapeutic agents
KR100838219B1 (en) A biodegradable microsphere composition which make possible continuous release of human growth hormone and a dosage form of microsphere
KR100871988B1 (en) Method of preparing water-free microencapsulation of hydrophilic macromolecular drugs within biodegradable microparticles and biodegradable microparticles

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

NENP Non-entry into the national phase

Ref country code: RU

122 Ep: pct application non-entry in european phase

Ref document number: 06716190

Country of ref document: EP

Kind code of ref document: A1