Biodegradable microsphere production method with enhanced productivity and production amount

Abstract

A productivity-enhanced method for producing biodegradable microspheres, according to the present invention, uses a mixed continuous phase in which a continuous phase (water and surfactant), conventionally used for extracting an organic solvent from an emulsion, is mixed with an oil for extracting an organic solvent such that an organic solvent which has been extracted into the continuous phase is quickly absorbed into an oil phase consisting of the oil for extracting an organic solvent, and the continuous phase can thus remain fresh. Therefore, compared to the conventional method, the amount of a fresh continuous phase used can be significantly reduced and the total amount of an emulsion injectable into a microsphere production tank can be increased, thereby significantly increasing productivity.

Description

Method for producing biodegradable microspheres with improved productivity and yield

[0001] The present invention relates to a method for producing microspheres with improved productivity and production volume, specifically characterized by adding an oil for organic solvent extraction to a continuous phase comprising water and a surfactant, which is conventionally used for extracting organic solvents within an emulsion.

[0002] Biodegradable polymers can be manufactured in the form of microspheres (e.g., particles having an average particle size in the nanometer to millimeter range, particularly 1 to 500 µm, particularly 10 to 150 µm) by various known technologies. Biodegradable polymer microspheres can be used as particle fillers for facial wrinkle improvement themselves and are usefully employed for the purpose of encapsulating biologically active or pharmaceutically active agents to provide continuous or delayed release of the agent or other active agent.

[0003]

[0004] As an example of the most frequently used method for manufacturing these biodegradable polymer microspheres,

[0005] The O / W emulsion method involves preparing a dispersed phase by dissolving a biodegradable polymer or a substance to be encapsulated (a drug or other active agent) with a biodegradable polymer in an organic solvent using a known method, and

[0006] The W / O / W emulsion method prepares a first aqueous phase by dissolving a drug in an aqueous solvent, prepares an oil phase by dissolving a biodegradable polymer in an organic solvent using a known method, and then prepares a W / O emulsion by mixing the first aqueous phase and the oil phase as a dispersed phase.

[0007] The S / O / W emulsion method involves dissolving a biodegradable polymer in an organic solvent using a known method, and then preparing a suspension (S / O) mixed with a powdered drug as the dispersed phase.

[0008] In the above O / W, W / O / W, or S / O / W emulsion methods, the dispersed phase prepared is dispersed in an aqueous solution (continuous phase) containing a surfactant to form an emulsion. Subsequently, as the organic solvent in the emulsion is extracted toward the continuous phase, it passes through the soft microspheres and gradually hardens to form hard microspheres.

[0009]

[0010] In the microsphere manufacturing process according to known technology, toxic solvents such as dichloromethane or chloroform are frequently used to dissolve biodegradable polymers and active agents. It is undesirable for these toxic solvents to remain within the microspheres, as their persistence in the final product acts as a general toxicity and a potential carcinogen. Furthermore, a mixture of various types of organic solvents is used to simultaneously and homogeneously dissolve the biodegradable polymer and the active agent. These organic solvents are dispersed in an aqueous solution to form an emulsion, and subsequently, depending on the solubility of the organic solvent in the aqueous solution or its affinity for the biodegradable polymer, they are extracted into and evaporated into the aqueous layer. However, it has been found that if organic solvents are not sufficiently removed from microspheres manufactured by known technology and remain in the final product, they adversely affect product stability, such as by accelerating the degradation of the polymer during the shelf life. In addition, if the extraction of the organic solvent from the emulsion to the continuous phase does not occur smoothly, the microspheres in the soft state may clump together or deform. Consequently, since a large amount of the continuous phase (an aqueous solution containing a surfactant) is used to facilitate the smooth extraction and evaporation of the organic solvent, it is not particularly environmentally friendly.

[0011]

[0012] Therefore, in the mass production process of biodegradable microspheres, there is a need to develop a production method that enables smooth extraction and evaporation of organic solvents while reducing the amount of continuous phase used.

[0013]

[0014] While devising a production method capable of smooth extraction and evaporation of organic solvents while reducing the amount of continuous phase used, the present invention was completed upon discovering that by adding an oil for organic solvent extraction to a general continuous phase (water and surfactant) conventionally used for extracting organic solvents within an emulsion, and using a mixed continuous phase comprising an oil for organic solvent extraction, water, and a surfactant within a microsphere manufacturing tank, the organic solvent extracted in the continuous phase is rapidly absorbed into the oil phase, thereby continuously maintaining the freshness of the continuous phase, resulting in a productivity improvement effect that significantly reduces the amount of fresh continuous phase used compared to conventional methods, and an effect that improves production volume by increasing the total amount of emulsion solution that can be injected into the microsphere manufacturing tank in a single process compared to conventional methods.

[0015] The objective of the present invention is to provide a method for mass production of biodegradable microspheres using a continuous phase with added oil for organic solvent extraction by improving the emulsion method for manufacturing microspheres.

[0016]

[0017] In order to achieve the above objective,

[0018] (a) A first emulsion comprising a dispersed phase containing a biodegradable polymer and an organic solvent, and an aqueous solution containing a surfactant and water as a continuous phase,

[0019] or a dispersed phase comprising a biodegradable polymer and an organic solvent, an aqueous solution comprising a surfactant and water as a continuous phase, and an oil for organic solvent extraction (O c A step of preparing a second emulsion by mixing a mixture of ); and

[0020] (b-1) In the second emulsion of step (a) above, the organic solvent in the dispersed phase is extracted into the continuous phase to form microspheres, or

[0021] (b-2) The first emulsion or second emulsion of step (a) is extracted using an oil (O) for organic solvent extraction. cIn a mixture formed by mixing ), the organic solvent in the dispersed phase is extracted into the continuous phase to form microspheres, or

[0022] (b-3) The first emulsion or second emulsion of step (a) is extracted using an oil (O) for organic solvent extraction. c A method comprising the step of mixing with a mixture of an aqueous solution containing a surfactant and water, and extracting an organic solvent within the dispersed phase into a continuous phase to form microspheres.

[0023] A method for mass production of biodegradable microspheres is provided.

[0024] The method for mass production of biodegradable microspheres according to the present invention uses a continuous phase (water and surfactant) used for extracting organic solvents in conventional emulsions, in which an oil for extracting organic solvents is added to the continuous phase. As a result, the organic solvent extracted in the continuous phase is rapidly absorbed into the oil phase, thereby continuously maintaining the freshness of the continuous phase. This results in an improved productivity effect that significantly reduces the amount of fresh continuous phase used compared to conventional methods, and an improved production volume effect that increases the total amount of emulsion solution that can be injected into the microsphere manufacturing tank in a single process compared to conventional methods.

[0025] In FIGS. 1 to 4b below, 1: Dispersed phase (DP) storage tank, 2: Continuous phase (CP) storage tank, 3: Oil for organic solvent extraction (O c ) storage tank, 4: microsphere manufacturing tank, 5: emulsion solution forming device, 6: first tangential flow filtration device (TFF-1), 7: second tangential flow filtration device (TFF-2), 8: waste, and 9: mixed continuous phase emulsion forming device.

[0026]

[0027] FIG. 1 is an oil for organic solvent extraction (O) according to an example of the present invention. cThis is a schematic diagram of a production method using ) (CP: Continuous phase, DP: Dispersed phase, Oil: Oil for organic solvent extraction).

[0028] FIG. 2 is an oil for organic solvent extraction (O) according to an example of the present invention. c This is a schematic diagram showing a production process that uses ) and additionally applies a tangential flow filtration (TFF) device.

[0029] FIGS. 3a and 3b are oils for organic solvent extraction (O) according to an example of the present invention. c An emulsion (W) emulsified with an aqueous solution containing ) a surfactant and water. m-e This is a schematic diagram showing a production process using phase).

[0030] FIGS. 4a and 4b are oils for organic solvent extraction (O) according to an example of the present invention. c An emulsion (W) emulsified with an aqueous solution containing ) a surfactant and water. m-e This is a schematic diagram showing a production process that uses a phase and additionally applies a tangential flow filtration (TFF) device.

[0031] FIG. 5 is a schematic diagram comparing an example of the amount of dispersed phase that can be injected into a microsphere manufacturing tank in a conventional microsphere production method and the production method of the present invention. The volume ratio of dispersed phase to continuous phase specified in FIG. 5 is an example and is not limited thereto.

[0032] Figure 6 is an SEM analysis image of the surface characteristics of microspheres prepared in Example 1, Comparative Examples 1-1 and 1-2, respectively.

[0033] Figure 7 is an SEM analysis image of the surface characteristics of microspheres prepared in Example 1, Comparative Examples 1-3 and 1-4, respectively.

[0034] FIG. 8 is an image showing whether the microspheres prepared in Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3, respectively, aggregated using an optical microscope.

[0035] FIG. 9 is an image of microspheres prepared in Examples 3-1 to 3-3, Comparative Example 3-1, and Comparative Example 3-2, respectively, observed under an optical microscope.

[0036] Figure 10 is an image of the microspheres prepared in Example 5 observed under an optical microscope.

[0037] Definition of Terms

[0038] The term "one or more types" in the present invention means a "number" corresponding to one or more. In the present invention, if a certain composition is one or more types, it may preferably be one type, two or more types, three or more types, one to three types, or one to two types, but is not limited thereto. The term "one or more types" may be used interchangeably with the terms "one or more" or "one or more" in the present invention.

[0039] The term “microsphere” in the present invention refers to a spherical particle having an average particle size of several to several hundred μm. Although not limited thereto, for example, the microsphere may be a microsphere having an average particle size of 1 to 500 μm, 1 to 250 μm, 1 to 150 μm, and particularly 10 to 150 μm.

[0040] The term “polymer blending” in the present invention means that two or more types of polymers are used in a single microsphere.

[0041] The term “microsphere blending” in the present invention refers to a blend of two or more types of microspheres having different compositions. The term “different compositions” means that one or more of the compositions constituting the microspheres are different from each other, and such compositions include, but are not limited to, drugs and types of polymers. For example, it may be a microsphere blend containing the same drug but different types of biodegradable polymers, a microsphere blend containing the same type of biodegradable polymer but different drugs, or a microsphere blend in which both the types of drugs and biodegradable polymers are different.

[0042] A dispersed phase (DP) refers to a discontinuous internal phase dispersed in the form of fine particles, droplets, or bubbles within a continuous phase (also called a continuous background material or dispersion medium) in a dispersion system (such as a colloid, emulsion, or suspension) composed of two or more immiscible substances. It is also referred to as a dispersed solute or internal phase, and in the case of an emulsion, it refers to a component that is divided into small parts and spread in an aqueous or oily solvent. The term "dispersed phase (DP)" in the present invention refers to an oil phase solution containing a biodegradable polymer and an organic solvent, or an oil phase solution, emulsion, or suspension further containing a drug. More specifically, the dispersed phase of the present invention comprises an oil phase solution containing a biodegradable polymer and an organic solvent; an oil phase solution containing a drug, a biodegradable polymer, and an organic solvent; It means a primary emulsion solution formed from a primary aqueous phase containing a drug and an oil phase solution containing a biodegradable polymer and an organic solvent; or a suspension containing a drug in powder form, a biodegradable polymer, and an organic solvent.

[0043] The term "oil (O) of the present invention" d"phase" refers to a solution containing a biodegradable polymer and an organic solvent used in the preparation of the dispersed phase, or a solution containing additional drugs, where 'O' is an abbreviation for 'oil' and the subscript 'd' is an abbreviation for 'dispersed'.

[0044] The term "aqueous (W)" of the present invention d "Phase" refers to a solution containing the drug and an aqueous solvent used in the preparation of the dispersed phase in the W / O / W method (i.e., an aqueous solution in which the drug is dissolved in an aqueous solvent), where 'W' is an abbreviation for 'water' and the subscript 'd' is an abbreviation for 'dispersed'.

[0045] The continuous phase (CP) refers to an external medium or medium that surrounds the dispersed phase and forms a continuous structure in a dispersion system. The term "continuous phase (CP)" in the present invention is an aqueous solution that forms an emulsion with the dispersed phase and serves to disperse microdroplets of the dispersed acid, and includes a surfactant.

[0046] The term “fresh continuous phase” in the present invention refers to an aqueous phase comprising a surfactant and water in the following step (a), more specifically (a-2), and “W c It is also expressed as "phase," where the subscript 'c' is an abbreviation for "continuous." The "fresh continuous phase" is mixed with an emulsion solution after being injected into a microsphere manufacturing tank, and transforms into a "continuous phase mixed with organic solvent" as the organic solvent is extracted from the microdroplets of the dispersed phase suspended in the emulsion solution. Therefore, in the present invention, "continuously maintaining the freshness of the continuous phase" means a state in which the concentration of the organic solvent mixed in the continuous phase is maintained at a low level during the organic solvent extraction process, and this can be achieved by the organic solvent mixed in the continuous phase moving to the oil for organic solvent extraction mixed together with the continuous phase, thereby maintaining a low concentration of the organic solvent in the continuous phase.

[0047] The term "mixed continuous phase" in the present invention refers to "W m It is expressed as "phase", where the subscript 'm' is an abbreviation for 'mixed'. The mixed continuous phase (W according to the present invention) m phase) consists of oil (Oc) for organic solvent extraction and continuous phase (W c It means that the aqueous solution is mixed in phase.

[0048] The term “first mixed continuous phase (W) of the present invention” m1 "phase)" means that it is used when preparing the emulsion of (a) above.

[0049] The term “second mixed continuous phase (W) of the present invention” m2 "phase)" means that it is used when extracting the organic solvent in the dispersed phase into the continuous phase in step (b-2) or (b-3).

[0050] The term "emulsified mixed continuous phase" in the present invention refers to an oil for organic solvent extraction (O c ) and continuous phase (W c It refers to a mixture of phase) in an emulsified form, that is, an emulsion consisting of an oil for organic solvent extraction and a continuous phase, and "W m-e It is expressed as "phase", where the subscript 'm-e' is an abbreviation for "emulsified mixed".

[0051] The term "oil for organic solvent extraction (O)" of the present invention c "" refers to oils used for extracting organic solvents used in the dispersed phase, and the above "oil phase (O d It is distinct from the composition of "phase".

[0052] The term "mixed continuous phase mixed with organic solvent" in the present invention refers to a state in which an organic solvent is mixed into the mixed continuous phase as the organic solvent in the dispersed phase of the emulsion is extracted into the mixed continuous phase within the microsphere manufacturing tank. Here, since the organic solvent evaporates through selective heating of the mixed continuous phase mixed with organic solvent, only a partial or trace amount of organic solvent may remain in the mixed continuous phase mixed with organic solvent, or the organic solvent may be completely evaporated.

[0053]

[0054] The present invention will be described in detail below.

[0055]

[0056] Mass production method of biodegradable microspheres using a mixed continuous phase

[0057] The present invention is,

[0058] (a) A first emulsion comprising a dispersed phase containing a biodegradable polymer and an organic solvent, and an aqueous solution containing a surfactant and water as a continuous phase,

[0059] or a dispersed phase comprising a biodegradable polymer and an organic solvent, an aqueous solution comprising a surfactant and water as a continuous phase, and an oil for organic solvent extraction (O c A step of preparing a second emulsion by mixing a mixture of ); and

[0060] (b-1) In the second emulsion of step (a) above, the organic solvent in the dispersed phase is extracted into the continuous phase to form microspheres, or

[0061] (b-2) The first or second emulsion of step (a) and the oil for organic solvent extraction (O c In a mixture formed by mixing ), the organic solvent in the dispersed phase is extracted into the continuous phase to form microspheres, or

[0062] (b-3) The first emulsion or second emulsion of step (a) is extracted using an oil (O) for organic solvent extraction. cA method for producing biodegradable microspheres is provided, comprising the step of mixing with a mixture of an aqueous solution containing a surfactant and water, and extracting an organic solvent in the dispersed phase into a continuous phase to form microspheres.

[0063]

[0064] In one example, when preparing the first emulsion in step (a) above,

[0065] In step (b-2), oil for organic solvent extraction (O) in the microsphere manufacturing tank c The first emulsion can be supplied with ) pre-filled, and

[0066] In step (b-3), oil for organic solvent extraction (O) in the microsphere manufacturing tank c The first emulsion can be supplied with the ) and continuous phase already filled, but is not limited thereto.

[0067]

[0068] In one example, when preparing a second emulsion in step (a) above,

[0069] In step (b-1), the second emulsion can be supplied while the continuous phase is pre-filled in the microsphere manufacturing tank, or the second emulsion can be supplied while the microsphere manufacturing tank is empty.

[0070] In step (b-2), oil for organic solvent extraction (O) in the microsphere manufacturing tank c The second emulsion can be supplied with the tank filled in advance, or the second emulsion can be supplied with the microsphere manufacturing tank empty.

[0071] In step (b-3), oil for organic solvent extraction (O) in the microsphere manufacturing tank c The second emulsion may be supplied with the continuous phase already filled, or with the microsphere manufacturing tank empty, but is not limited thereto.

[0072]

[0073] In one example, the dispersion phase may additionally contain a drug.

[0074] In one example, the oil for organic solvent extraction may be included in an amount of 10 to 1,000 parts by weight based on 100 parts by weight of the organic solvent of step (a).

[0075] In one example, the oil for organic solvent extraction in step (a) above may be used by simply mixing it with an aqueous solution containing a surfactant and water, or by emulsifying it.

[0076] In one example, the oil (Oc) for organic solvent extraction in step (b-3) above may be used by simply mixing it with an aqueous solution containing a surfactant and water, or by emulsifying it.

[0077] In one example, step (b-1), step (b-2), or step (b-3) may involve additionally injecting a fresh continuous phase while extracting the organic solvent in the dispersed phase into the continuous phase. In one example, the fresh continuous phase may further include an initial release inhibitor.

[0078]

[0079] Below, a method for mass-producing microspheres according to the present invention is described step by step.

[0080]

[0081] In the method for mass production of microspheres according to the present invention, step (a) is a step of preparing a dispersed phase and a continuous phase, respectively.

[0082] In one example, the above step (a) is,

[0083] (a-1) A step of preparing a dispersed phase comprising a biodegradable polymer and an organic solvent, or a dispersed phase comprising a biodegradable polymer, a drug and an organic solvent,

[0084] (a-2) An aqueous solution (W) containing a surfactant and water c phase) or oil for organic solvent extraction (O cA mixture (W) containing a surfactant and water. m1 Step of preparing the phase in a continuous state;

[0085] (a-3) The dispersed phase of step (a-1) and the aqueous solution (W) of step (a-2) c phase or mixture (W m1 It may include a step of preparing an emulsion by mixing the phase.

[0086]

[0087] In one example, in step (a), an aqueous solution (W) comprising a surfactant and water is mixed with the dispersed phase as a continuous phase. c A first emulsion may be prepared using only the phase), or a mixture comprising an oil (Oc) for organic solvent extraction, a surfactant, and water together with the dispersed phase (hereinafter, “first mixed continuous phase (W)”). m1 A second emulsion may also be prepared using the above organic solvent extraction oil (O phase). c A mixture containing a surfactant and water may be a simple mixture of an aqueous solution containing a surfactant and water and an oil for organic solvent extraction, but may be emulsified through an emulsion forming device, etc.

[0088] In one example, in the second emulsion of step (a) above, the oil for organic solvent extraction comprises a continuous phase containing the surfactant and water and an oil for organic solvent extraction (O cBased on the total volume of the mixture, the lower limit may be 0.01 (v / v)% or more, 0.03 (v / v)% or more, 0.05 (v / v)% or more, 0.07 (v / v)% or more, or 0.10 (v / v)% or more, and the upper limit may be 28 (v / v)% or less, 27 (v / v)% or less, 26 (v / v)% or less, or 25 (v / v)% or less, and the range consisting of a combination of these upper and lower limits, for example, 0.01 to 25 (v / v)%. If it exceeds 25 (v / v)%, there may be a problem where an O / W type emulsion is not formed well, or even if it is formed, the particle size distribution of the microspheres produced is non-uniform (see Experimental Example 5).

[0089]

[0090] In one example, the dispersion phase of step (a) above may be the dispersion phase of the O / W method, the dispersion phase of the W / O / W method, or the dispersion phase of the S / O / W method.

[0091] Specifically, the dispersed phase of the above O / W method is an oil phase (O) in which a biodegradable polymer alone or a biodegradable polymer and a drug are dissolved in an organic solvent. d It may be a phase. In other words, the dispersed phase of the above O / W method may be an oil phase solution in which a biodegradable polymer is dissolved in an organic solvent; or an oil phase in which a drug and a biodegradable polymer are dissolved in an organic solvent.

[0092] The dispersed phase of the above W / O / W preparation method is a first aqueous phase (W) in which the drug is dissolved in an aqueous solvent. d phase) and the oil phase (O) in which biodegradable polymers are dissolved in an organic solvent d W prepared by mixing phase) d / O d It may be an emulsion. That is, the dispersed phase of the above W / O / W preparation method is formed by dissolving a drug in an aqueous solvent to form a first aqueous phase (W d Prepare the oil phase) and dissolve the biodegradable polymer in an organic solvent to prepare the oil phase (O dAfter preparing the phase), the W mixture of the first aqueous phase and the oil phase is prepared. d / O d An emulsion can be prepared as a dispersed phase.

[0093] The dispersed phase of the above S / O / W method is a suspension (S) prepared by suspending a biodegradable polymer and a drug in powder form in an organic solvent. d / O d It may be a phase. For example, the dispersed phase of the above S / O / W method may be a suspension (S) in which a biodegradable polymer and a drug in powder form are mixed in an organic solvent that dissolves the biodegradable polymer. d / O d The phase) can be prepared as a dispersed phase.

[0094] In the dispersion phase of the above W / O / W method, examples of the above aqueous solvents may include water (e.g., distilled water, purified water, and water for injection, etc.), PBS (Phosphate buffered saline), TBS (Triss buffered saline), acetate buffer, citrate buffer, glycine-HCl buffer, ammonium bicarbonate buffer, sodium hydroxide aqueous solution, urea aqueous solution, etc., either used alone or in a mixture of two or more.

[0095] In the dispersion phase of the above S / O / W preparation method, the average particle size of the drug in powder form may be set to an upper limit of 10 μm or less, 8 μm or less, 6 μm or less, 5 μm or less, 4 μm or less, or 3 μm or less, but is not limited thereto. In addition, the average particle size of the drug in powder form may be set to a lower limit of 0.001 μm or more, 0.005 μm or more, 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, or 1 μm or more, but is not limited thereto. The average particle size of the drug in powder form may be used within a range obtained by combining the above lower and upper limit values, but is not limited thereto.

[0096]

[0097] In one example, the organic solvent of step (a) may be a single solvent selected from the group consisting of dichloromethane, dimethyl carbonate, chloroform, ethyl acetate, methyl ethyl ketone, acetone, acetonitrile, dimethyl sulfoxide, dimethylformamide, enmethylpyrrolidone, acetic acid, methanol, ethanol, propyl alcohol, and benzyl alcohol, or a mixture of two or more organic solvents.

[0098] In one example, the organic solvent of step (a) may be a mixture of two or more organic solvents. As a specific embodiment, the mixture of organic solvents may be a mixture of an organic solvent that is miscible with water and an organic solvent that is not miscible with water. In this case, it is preferable to use the organic solvent that is not miscible with water in an amount of at least 50% (v / v), 60% (v / v), 50 to 99.9% (v / v), 50 to 90% (v / v), 50 to 80% (v / v), 50 to 70% (v / v), 60 to 90% (v / v), or 60 to 80% (v / v) relative to the total volume of the mixture of organic solvents.

[0099] In one example, the organic solvent of step (a) may be i) dichloromethane or ethyl acetate; or ii) a mixed organic solvent of dichloromethane or ethyl acetate and one or more of dimethyl sulfoxide, methylpyrrolidone, methanol, benzyl alcohol, and acetic acid. More specifically, the organic solvent of step (a) may be i) dichloromethane; or ii) a mixed organic solvent of dichloromethane and one or more of dimethyl sulfoxide, methylpyrrolidone, methanol, benzyl alcohol, and acetic acid.

[0100]

[0101] The type of biodegradable polymer in step (a) above is not particularly limited, but includes polylactide (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) (PLGA), polydioxanone, polycaprolactone (PL), polylactide-co-glycolide-co-caprolactone (PLGC), polylactide-co-hydroxymethyl glycolide (PLGMGA), polyalkylcarbonate, polytrimethylenecarbonate (PTMC), and polylactide-co-trimethylenecarbonate (PLTMC). A polymer selected from the group consisting of polyhydroxybutyric acid (PHB), polyhydroxybutyrate-co-hydroxyvalerate (PHBV), polyorthoester, polyanhydride, polyanhydride-co-imide, polypropylene fumarate, pseudo-polyaminoacid, polyalkyl cyanoacrylate, polyphosphazene, polyphosphoester, polysaccharide, and poly(butylene succinate-co-lactic acid) (PBSLA); a simple mixture of two or more of the selected polymers (specifically two to three types, more specifically two types);It may be one or more selected from the group consisting of a copolymer of the selected polymer and polyethylene glycol (PEG); and a polymer-sugar complex in which a sugar is bonded to the selected polymer or copolymer (specifically 1 to 3 types, more specifically 1 to 2 types). Specifically, polylactide (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) (PLGA), polycaprolactone (PL), etc., may be used alone or in a mixture of two or more types. More specifically, polylactide (PLA), poly(lactide-co-glycolide) (PLGA), etc., may be used alone or in a mixture of two or more types.

[0102]

[0103] The above-mentioned biodegradable polymer may be used with an intrinsic viscosity of 0.08 to 1.7 dL / g. Specifically, the intrinsic viscosity of the above-mentioned biodegradable polymer may be used in various ranges by considering manufacturing conditions such as the type of drug, drug release characteristics, and manufacturing process. The lower limit of the intrinsic viscosity of the above biodegradable polymer is 0.08 dL / g or more, 0.14 dL / g or more, 0.15 dL / g or more, 0.16 dL / g or more, 0.20 dL / g or more, 0.25 dL / g or more, 0.26 dL / g or more, 0.32 dL / g or more, 0.33 dL / g or more, 0.39 dL / g or more, 0.40 dL / g or more, 0.45 dL / g or more, 0.50 dL / g or more, 0.55 dL / g or more, 0.61 dL / g or more, 0.70 dL / g or more, 0.71 dL / g or more, 0.76 dL / g or more, 0.80 dL / g or more, 0.83 It may be dL / g or more, 0.90 dL / g or more, 0.95 dL / g or more, 1.00 dL / g or more, or 1.30 dL / g or more, and the upper limit is 0.16 dL / g or less, 0.20 dL / g or less, 0.22 dL / g or less, 0.24 dL / g or less, 0.25 dL / g or less, 0.35 dL / g or less, 0.40 dL / g or less, 0.42 dL / g or less, 0.44 dL / g or less, 0.49 dL / g or less, 0.50 dL / g or less, 0.54 dL / g or less, 0.60 dL / g or less, 0.68 dL / g or less, 0.70 dL / g or less, 0.74 It may be dL / g or less, 0.75 dL / g or less, 0.85 dL / g or less, 0.90 dL / g or less, 0.93 dL / g or less, 0.94 dL / g or less, 1.00 dL / g or less, 1.20 dL / g or less, 1.30 dL / g or less, or 1.70 dL / g or less. The intrinsic viscosity of the above biodegradable polymer may be used within a range obtained by combining the above lower and upper limit values, but is not limited thereto. The above intrinsic viscosity refers to the value measured at a concentration of 0.1% (w / v) in chloroform at 25°C using a Ubbelohde viscometer.

[0104]

[0105] Depending on manufacturing conditions such as the type of drug, drug release characteristics, and manufacturing process, the above intrinsic viscosity may be used in various ranges. In this regard, if the above upper limit is exceeded, there may be problems such as excessive delay in drug release (occurrence of a lag phase), reduced reproducibility of microsphere manufacturing, and the need to use an excessive amount of organic solvent due to high viscosity. If the above lower limit is below, there may be problems such as burst release of the drug or difficulty in exhibiting a long-term sustained release pattern due to insufficient molecular weight of the polymer. In one embodiment, in the case of a polymer blend using two or more types of polymers, a polymer with low intrinsic viscosity and a polymer with high intrinsic viscosity may be mixed so that the mixed intrinsic viscosity (final intrinsic viscosity) is included within a desirable range of the above intrinsic viscosity.

[0106]

[0107] In one example, the biodegradable polymer may include a hydroxyl group, a carboxyl group, a methoxy group, a methyl group, an amine group, or an ester group at one or both ends.

[0108] In one example, the biodegradable polymer may comprise two or more repeating units.

[0109]

[0110] In this specification, if the biodegradable polymer is a copolymer composed of two or more repeating units, the ratio of each repeating unit may be defined as a molar ratio (mol%) or weight ratio (wt%) based on the repeating unit within the polymer. The repeating unit ratio reflects the chemical composition of the actually formed polymer. The repeating unit ratio is, for example, 1 H NMR or 13It is calculated using the peak integral value specific to each repeating unit in the 3C NMR spectrum, and internal standards may be used to improve quantification if necessary. Additionally, the results may be verified by applying FT-IR, elemental analysis, or post-degradation analysis (GC / LC, etc.) as auxiliary methods. The above repeating unit ratio is a factor that influences the crystallinity, glass transition temperature, molecular weight, mechanical strength, and biodegradation rate of the copolymer, and can be appropriately adjusted according to polymerization conditions and applications. In the present invention, the specific repeating unit ratio is presented as an exemplary range for realizing the physical properties and functions of the copolymer and is not to be interpreted as being limited thereto.

[0111]

[0112] For example, when poly(lactide-co-glycolide) is used as the biodegradable polymer, the molar ratio of lactide to glycolide, which are repeating units in the copolymer, may be 40:60 to 90:10, 45:55 to 85:15, 50:50 to 85:15, or 50:50 to 75:25, for example, 40:60, 45:55, 50:50, 55:45, 60:40, 65:35, 70:30, 75:25, 80:20, 85:15, or 90:10.

[0113]

[0114] Examples of commercially available biodegradable polymers that can be used in the present invention include Evonik’s Resomer® series and Corbion’s PURASORB® series. For example, the above-mentioned Evonik Resomer series biodegradable polymers may include RG501H, RG502, RG502H, RG503, RG503H, RG504, RG504H, RG505, RG653H, RG750S, RG752H, RG752S, RG753H, RG753S, RG755S, RG756S, RG757S, RG858S, R202H, R203H, R202S, R203S, R205H, R205S, etc., and the above-mentioned Covion PURASORB series biodegradable polymers may include PDL O2A, PDL O2, PDL O4A, PDL O4, PDL O5, PDLG 7502A, PDLG 7502, PDLG 7507, PDLG 7510, PDLG 5002A, PDLG 5002, PDLG 5004A, PDLG 5004, PDLG 5010, PDLG 5505G, PL 10, PL 18, PL 24, PL 32, PL 38, PL 65, PLDL 7024, PLDL, 7028, PLDL, 7038, PLDL 7060, PLDL 8038, PLDL 8058, PG 20, PLG 1017, PLG 8218, PLG 8523, PLG 8531, PC 02, PC 04, PC 08, PC 12, PC 17, PLC 7015, etc. can be used.

[0115]

[0116] In addition, the biodegradable polymer being a simple mixture of two or more (i.e., a simple mixture comprising two or more of the polymers selected above) may include two or more polymers of different types among the polymers exemplified above without limitation, or it may be a combination or blend of polymers of the same type. If polymers of the same type are used, a combination of polymers in which at least one of the intrinsic viscosity of the polymer, the molar ratio of repeating units, and the terminal groups of the polymer is different may be used.

[0117] For example, the above two or more types of biodegradable polymers may be a combination of polymers of different types (e.g., PLA and PLGA); a combination of polymers of the same type but having different intrinsic viscosities (e.g., a combination or blend of two or more PLAs having different intrinsic viscosities; a combination or blend of two or more PLGAs having different intrinsic viscosities); a combination or blend of polymers of the same type but having different repeating unit molar ratios (e.g., a combination or blend of PLGAs with Lactide:glycolide ratios of 50:50 and 65:35, respectively); a combination of polymers of the same classification but having different terminal groups (e.g., PLA or PLGA with carboxylic acid terminal groups; and a combination or blend of PLA or PLGA with methyl-blocked terminal groups); or a combination or blend of two or more polymers in which two or more of the intrinsic viscosity, repeating unit molar ratio, and terminal groups are different.

[0118] Here, a combination of two or more polymers having different repeating units includes a combination of a biodegradable polymer having only one repeating unit and a biodegradable polymer having two or more repeating units. In this case, any one of the repeating units of the biodegradable polymer having two or more repeating units may be identical to the repeating unit of the biodegradable polymer having only one repeating unit (e.g., a combination of PLGA and PLA).

[0119]

[0120] In addition, as a specific example, when there are two types of the above-mentioned different biodegradable polymers, they can be mixed and used in various content ratios. For example, the content ratio may be 0.5:10 to 10:0.5, 0.5:8 to 8:0.5, 1:10 to 10:1, 1:4 to 4:1, 1:3 to 3:1, or 1:2 to 2:1 by weight, but is not limited thereto.

[0121]

[0122] The content of the biodegradable polymer in the microspheres according to the present invention may be selected as a lower limit of 20 wt% or more, 25 wt% or more, 26 wt% or more, 27 wt% or more, 28 wt% or more, 29 wt% or more, 30 wt% or more, 35 wt% or more, 40 wt% or more, 45 wt% or more, 50 wt% or more, 55 wt% or more, 60 wt% or more, 65 wt% or more, 70 wt% or more, 75 wt% or more, 80 wt% or more, 85 wt% or more, 90 wt% or more, or 95 wt% or more, based on the total weight of the microspheres, and 100 wt% or less, 95 wt% or less, 90 wt% or less, 85 wt% or less, 80 wt% or less, 75 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 50 wt% or less, The upper limit may be selected as 45% by weight or less, 40% by weight or less, 35% by weight or less, 30% by weight or less, 29% by weight or less, 28% by weight or less, 27% by weight or less, 26% by weight or less, 25% by weight or less, or 20% by weight or less. The content of the biodegradable polymer in the microspheres may be included in a range consisting of a combination of the upper and lower limits with respect to the total weight of the microspheres. For example, it may be 20 to 100 wt%, 25 to 100 wt%, 30 to 100 wt%, 35 to 100 wt%, 40 to 100 wt%, 45 to 100 wt%, 50 to 100 wt%, 55 to 100 wt%, 60 to 100 wt%, 65 to 100 wt%, 70 to 100 wt%, 75 to 100 wt%, 80 to 100 wt%, or 85 to 100 wt%, but is not limited thereto.

[0123] In one example, if the dispersed phase of step (a) comprises an organic solvent in which a blend of two or more biodegradable polymers (e.g., PLA and PLGA) is dissolved, then finally, not only microspheres containing each of the biodegradable polymers alone, but also polymer blend microspheres containing all of the two or more biodegradable polymers can be produced (e.g., microspheres containing both PLA and PLGA).

[0124]

[0125] The type of drug in step (a) above is not particularly limited, and water-soluble drugs, fat-soluble drugs, poorly soluble drugs, etc., can all be used. Specifically, small molecule therapeutics, synthetic compound therapeutics, peptide therapeutics, antibody therapeutics, protein therapeutics, nucleic acid therapeutics, gene therapeutics, cell therapeutics, antibody-drug conjugates (ADC) therapeutics, radiopharmaceutical therapy (RPT), etc., can be used alone or in combination of two or more types.

[0126]

[0127] The above nucleic acid therapeutic agent may be one or more selected from the group consisting of DNA, RNA, microRNA (microRNA, miRNA), small RNA (smRNA), small interfering RNA (siRNA), piRNA (piwi-interacting RNA, piRNA), small nucleolar RNA (snoRNA), tRNA-derived small RNA (tsRNA), small rDNA-derived RNA (srRNA), small nuclear RNA (U-RNA), and long noncoding RNA (lncRNA).

[0128]

[0129] The above drugs are, for example, dementia treatments; Parkinson's disease treatments; anticancer agents; antipsychotic drugs such as anti-anxiety agents, antidepressants, tranquilizers, and psychotropic agents; cardiovascular treatments such as hyperlipidemia treatments, hypertension treatments, hypotension treatments, antithrombotic agents, vasodilators, and arrhythmia treatments; epilepsy treatments; seizure treatments; gastrointestinal treatments such as anti-ulcer agents; rheumatoid arthritis treatments; antispasmodics; tuberculosis treatments; muscle relaxants; osteoporosis treatments; erectile dysfunction treatments; hemostatic agents; hormones such as sex hormones; diabetes treatments; obesity treatments; non-alcoholic fatty liver disease treatments; antibiotics; antifungals; antivirals; antipyretic analgesics and anti-inflammatory drugs; autonomic nervous system regulators; steroidal anti-inflammatory drugs such as corticosteroids; diuretics; antidiuretics; analgesics; anesthetics; antihistamines; protozoal agents; antianemia agents; antiasthmatic agents; anticonvulsants; antidetoxins; and migraines. Antiemetics; anti-Parkinson's agents; anticonvulsants; antiplatelet agents; antitussive and expectorant agents; bronchodilators; cardiac stimulants; immunomodulators; protein drugs; gene drugs, etc., may be used alone or in combination of two or more. Specifically, dementia treatments, Parkinson's disease treatments, anticancer agents, antipsychotic drugs, hyperlipidemia treatments, hypertension treatments, epilepsy treatments, gastrointestinal treatments, rheumatoid arthritis treatments, antispasmodics, tuberculosis treatments, muscle relaxants, arrhythmia treatments, osteoporosis treatments, erectile dysfunction treatments, hemostatic agents, antivirals, hormones, antibiotics, diabetes treatments, obesity treatments, non-alcoholic fatty liver disease treatments, antifungals, antithrombotic agents, antipyretic analgesic anti-inflammatory drugs, steroidal anti-inflammatory drugs, etc., may be used alone or in combination of two or more.

[0130]

[0131] Specific examples of the above drugs include donepezil, memantine, rivastigmine, entecavir, lamivudine, rotigotine, ropinirol, bupivacaine, ropivacaine, meroxicam, buprenorphine, fentanyl, nimodipine, granisetron, dexamethasone, triamcinolone, cytarabine, kammerstin, tamsolucin, polmacoxib, testosterone, estradiol, risperidone, paliperidone, olanzapine, aripiprazole, goserelin, leuprolide, triptorelin, buserelin, naparelin, deslorelin, octreotide, pasireotide, lanreotide, vafretide, exenatide, liraglutide, lixisenatide, semaglutide, cagrilintide, terzepatide, Dulaglutide, retalutide, mazdutide, 5-alpha reductase inhibitors (e.g., finasteride, dutasteride, etc.), brexpiprazole, insulin glargine, insulin degludec, insulin icodec, steroidal anti-inflammatory drugs, amicretin, Monlunabant (Novo Nordisk's INV-202), orforglipron, erorarintide (Eli Lilly's LY-3841136), DACRA QW II (Eli Lilly's LY-3541105), nisotirostide (Eli Lilly's LY-3457263), survodutide, Ecnoglutide, dapiglutide, ZP8396 from Zealand, VK2735 from Viking Therapeutics, pemvidutide, bamadutide, cotadutide, utreglutide, PYY1875 from Novo Nordisk, CT-388 from Roche / Carmot Therapeutics, etc., may be used alone or in combination of two or more.As an example of using a combination of two types, semaglutide and cagrilintide can be used together.

[0132]

[0133] Specific examples of the above-mentioned steroidal anti-inflammatory agents include 21-acetoxypregnenolone, alclomethasone, algestone, amhimnonide, beclomethasone, betamethasone, budesonide, chloroprednisone, clobetasol, clobetasone, clocortolone, cloprednol, corticosterone, cortisone, cortivazol, deflazacort, desonide, desoximethasone, dexamethasone, dexamethasone acetate, dexamethasone phosphate, diflorasone, diflucortolone, difluprednate, enoxolone, fluazacort, flucloronide, flumethasone, flunisolide, fluocinolone acetonide, Fluosinonide, Flucortin butyl, Fluocortolon, Fluorometholone, Fluperolone acetate, Fluprednidene acetate, Fluprednisolone, Flurandrenolide, Fluticasone propionate, Formocortal, Halcinonide, Halobetasol propionate, Halomethasone, Halofredone acetate, Hydrocortamate, Hydrocortisone, Loteprednol etabonate, Mazipredone, Medrysone, Meprednisone, Methylprednisolone, Mometasone furoate, Paramethasone, Prednicarbate, Prednisolone, Prednisolone 25-Diethylamino-Acetate, Prednisolone Sodium Phosphate, Prednisone, Prednival, Prednylidene, Rimexolone, Tixocortol, Triamcinolone, Triamcinolone Acetoneide, Triamcinolone Venetonide, Triamcinolone Hexacetonide,Beclomethasone dipropionate, betamethasone, budesonide, deflazacort, dexamethasone, dexamethasone acetate, dexamethasone phosphate, difluprednate, epinephrine, fludrocortisone, fluocinolone acetonide, fluocortin, fluorometholone, fluticasone, hydrocortisone, methylprednisolone, prednisolone, prednisone, triamcinolone, etc., alone Alternatively, two or more types can be used in combination.

[0134]

[0135] In addition, the above-mentioned drugs may be used as derivatives or in the form of pharmaceutically acceptable salts. As salts, any salt commonly used in the art may be used without limitation. The term "pharmaceutically acceptable salt" in this invention refers to any organic or inorganic addition salt of the said compound at a concentration that has a relatively non-toxic and harmless active effect on the patient, such that side effects caused by the salt do not impair the beneficial efficacy of the active ingredient. For example, pamoate may be used as the pharmaceutically acceptable salt.

[0136]

[0137] Furthermore, the content of the drug in the microspheres according to the present invention may be selected as a lower limit of 5 wt% or more, 10 wt% or more, 15 wt% or more, 20 wt% or more, 25 wt% or more, 30 wt% or more, 35 wt% or more, 40 wt% or more, 45 wt% or more, 50 wt% or more, 55 wt% or more, 60 wt% or more, 65 wt% or more, 70 wt% or more, 71 wt% or more, 72 wt% or more, 73 wt% or more, 74 wt% or more, or 75 wt% or more, based on the total weight of the microspheres, and 80 wt% or less, 75 wt% or less, 74 wt% or less, 73 wt% or less, 72 wt% or less, 71 wt% or less, 70 wt% or less, 65 wt% or less, 60 wt% or less, 55 wt% or less, 50 wt% or less, 45 wt% or less, The upper limit may be selected as 40% by weight or less, 35% by weight or less, 30% by weight or less, 25% by weight or less, 20% by weight or less, 15% by weight or less, or 10% by weight or less. The content of the drug in the microspheres may be included in a range consisting of a combination of the lower and upper limits with respect to the total weight of the microspheres. For example, it may be 5 to 80 wt%, 5 to 75 wt%, 5 to 74 wt%, 5 to 73 wt%, 5 to 72 wt%, 5 to 71 wt%, 5 to 70 wt%, 5 to 65 wt%, 5 to 60 wt%, 5 to 55 wt%, 5 to 50 wt%, 5 to 45 wt%, 5 to 40 wt%, 5 to 35 wt%, 5 to 30 wt%, 5 to 25 wt%, 5 to 20 wt%, 5 to 15 wt%, or 5 to 10 wt%, but is not limited thereto.

[0138]

[0139] Optionally, the dispersed phase of step (a) may further include, either alone or in combination of two or more release regulators such as butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecylic acid, behenic acid, arachidic acid, isocrotonic acid, oleic acid, elaidic acid, sorbic acid, linoleic acid, arachidonic acid, benzoic acid, hydroxynaphthoic acid, napadicylic acid, naphthalenesulfonic acid, and pamosan. Specifically, pamosan may be used alone, but is not limited thereto. In one example, the release regulator is the oil phase (O) of the O / W method. d phase), oil phase of W / O / W method (O d phase), or suspension of the S / O / W method (S d / O d It can be added to and used in the phase.

[0140]

[0141] In one example, the water in step (a) above may be one or more selected from the group consisting of purified water, distilled water and water for injection.

[0142] In one example, the surfactant in step (a) is not particularly limited and any surfactant that can help the dispersed phase form a dispersed phase emulsion of stable droplets within the continuous phase may be used. Specifically, the surfactant may be polyvinyl alcohol, methylcellulose, polyvinylpyrrolidone, carboxymethylcellulose, lecithin, gelatin, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene castor oil derivative, etc., used alone or in a mixture of two or more. More specifically, the surfactant may be polyvinyl alcohol.

[0143]

[0144] In one example, the content of the surfactant in the continuous phase may be 0.01 w / v% to 20 w / v% based on the total volume of the continuous phase containing the surfactant, specifically 0.03 w / v% to 18 w / v%, 0.05 w / v% to 15 w / v%, 0.07 w / v% to 10 w / v%, or 0.1 w / v% to 5 w / v%, and may be a combination of the lower and upper limits of the ranges described above. If the surfactant content is less than 0.01 w / v%, a dispersed phase emulsion in the form of droplets may not be formed in the continuous phase, and if the surfactant content exceeds 20 w / v%, there may be difficulty in removing the surfactant after microspheres are formed in the continuous phase due to the excess surfactant.

[0145]

[0146] In one example, the continuous phase may further include methanol, ethanol, propyl alcohol, ethyl acetate, etc., either alone or in a mixture of two or more, for the purpose of controlling the extraction rate of an organic solvent from a dispersed phase in an emulsion state. Additionally, the continuous phase may further include sodium chloride for the purpose of controlling osmotic pressure.

[0147]

[0148] The above continuous phase aqueous solution (W c There are no specific restrictions on the temperature of the phase, but it may be heated to a level close to the boiling point of the organic solvent used to prepare the dispersed phase, or it may be used at room temperature without heating. If heated to a level close to the boiling point of the organic solvent, it may be advantageous for the selective evaporation of the organic solvent that is mixed into the dispersed phase after the organic solvent of the dispersed phase is extracted from the emulsion suspended in the mixed continuous phase. If the drug used is sensitive to high temperatures, it may be heated to a level that does not affect the activity of the drug. Additionally, the continuous phase may be prepared at room temperature and heated in a microsphere preparation tank, such as an emulsion storage tank.

[0149]

[0150] The method of homogeneously mixing the dispersed phase and the continuous phase or the continuous phase and the oil for organic solvent extraction in step (a) above is not particularly limited, but in one example, the formation of the emulsion solution in step (a) above may be performed using a membrane emulsification device, an inline mixer, a static mixer, a microfluidic system, etc., and any known emulsion solution forming device may be used.

[0151]

[0152] For example, in FIGS. 1 to 4, the emulsion solution forming device (5) may be a membrane emulsification device, an inline mixer, a static mixer, a microfluidic system, etc., and the mixing continuous phase emulsion forming device (9) may be an inline mixer, a static mixer, etc.

[0153]

[0154] In the method for producing biodegradable microspheres according to the present invention, steps (b-1), (b-2), and (b-3) are steps of forming microspheres by extracting an organic solvent in the dispersed phase of the first emulsion or second emulsion prepared in step (a) into a continuous phase.

[0155] For example, according to step (b-1) above, the second emulsion is injected into the continuous phase, or according to (b-2), the first emulsion or the second emulsion is injected into the oil (Oc) for organic solvent extraction, or according to (b-3), the first emulsion or the second emulsion is injected into a mixture of the oil (Oc) for organic solvent extraction and the continuous phase, so as to form a mixed continuous phase (W) in which the continuous phase of the emulsion and the oil for organic solvent extraction are mixed within a microsphere manufacturing tank (emulsion storage tank). m phase), more specifically, the second mixed continuous phase (W m2 A phase) is formed, and the organic solvent present in the dispersed phase of the emulsion is extracted by the oil for extracting the organic solvent in this mixed continuous phase.

[0156] By using a mixed continuous phase in which the oil for organic solvent extraction and the continuous phase are mixed, the continuous phase (W) is used without using the conventional oil for organic solvent extraction. c Unlike production methods that use only the phase, the amount of the continuous phase used is reduced to a remarkable level, thereby increasing the amount of the dispersed phase which is ultimately directly related to the production volume of microspheres, making mass production of microspheres possible while maintaining the shape and characteristics of the microspheres stably.

[0157]

[0158] In one example, in step (b-3) above, the oil for organic solvent extraction (O c ) is a continuous phase (W c It may be a form simply mixed with phase) (see Figs. 1 and 2).

[0159] In one example, in step (b-3) above, the oil for organic solvent extraction (O c ) is the continuous phase (W) of step (a) above. c phase (aqueous solution) and an emulsion mixed in an emulsified form (i.e., an emulsified mixed continuous phase (W m-e The above emulsified mixed continuous phase can be introduced into a microsphere manufacturing tank as a phase). For example, the above emulsified mixed continuous phase can be introduced into an oil for organic solvent extraction (O) through a mixed continuous phase emulsion forming device (9). c ) and continuous phase (W c The phase) can also be emulsified and used (see FIG. 3a, FIG. 3b, FIG. 4a and FIG. 4b).

[0160] Here, oil for organic solvent extraction (O c ) is a continuous phase (W c phase) and simply mixed continuous phase (W m In the case where a phase) is formed, a continuous phase (W c Oil for organic solvent extraction (O) on top of the phase) layer c Phase separation occurs where the ) layer is located, so the manufactured microspheres are the continuous phase (W of the lower layer) c It can be located in the phase.

[0161] In addition, oil for organic solvent extraction (O c ) and continuous phase (W c An emulsion composed of phase) (i.e., an emulsified mixed continuous phase (W m-e When using the phase), the continuous phase (W)) in the microsphere manufacturing tank c phase) and oil for organic solvent extraction (O c Since ) exists without layer separation, the manufactured microspheres are an emulsified mixed continuous phase (W m-e They can be located together in the phase.

[0162]

[0163] Here, the "emulsified mixed continuous phase (W m-e "phase" is an oil for organic solvent extraction (O c ) and continuous phase (W c The continuous phase (W) is emulsified through a mixing continuous phase emulsion forming device (9). c The emulsion can be maintained by a surfactant contained in the phase). In addition, the emulsified mixed continuous phase (W m-e To maintain the emulsion state of the continuous phase (W phase), c The surfactant contained in the phase) can be replaced with another surfactant, and the continuous phase (W c An additional surfactant may be used in addition to the surfactant included in the phase.

[0164] In addition, the above "emulsified mixed continuous phase (W m-e It is desirable to form the emulsion size of the "phase" smaller than the pore size of the filter membrane equipped in the "Tangential flow filtration (TFF)" device so that it can be easily discharged.

[0165]

[0166] In the production method according to the present invention, the oil for organic solvent extraction (O cAny oil with excellent miscibility with organic solvents may be used. Specifically, one or more fractionated oils, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid triglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid diglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid monoglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acids, ethyl oleate, one or more propylene glycol C6-C 18 (Specifically, C6-C 12 ) Fatty acid diesters, etc., may be used alone or in a mixture of two or more types. For example, one or more medium-chain fatty acids (C6-C 12 Medium-chain triglyceride (MCT) may be used. Here, the three or two fatty acid chains included in the triglyceride or diglyceride, respectively, may be the same or different.

[0167] The above MCT can be manufactured and used by methods known in the art, and MIGLYOL ® 810, 812, 812N, 818, 829 (Sasol Germany GmbH, Witten, Germany) or NEOBEE ® You may also use commercially available products such as 1053, 895, M-5 (Stepan Company, Northfield, Il.).

[0168] The above propylene glycol C6-C 18 (Specifically, C6-C 12 ) Fatty acid diesters can be prepared and used by methods known in the art, and MIGLYOL ®You may also use a product available on the market as 840 (Sasol Germany GmbH, Witten, Germany).

[0169] The above fractionated oil may be used alone or in a mixture of two or more types, such as coconut oil, palm oil, palm kernel oil, sesame oil, soybean oil, almond oil, rapeseed oil, corn oil, sunflower oil, peanut oil, olive oil, castor oil, soybean oil, safflower oil, and cottonseed oil.

[0170]

[0171] In the production method according to the present invention, the continuous phase finally mixed in step (b-2) or step (b-3) and the oil for organic solvent extraction (O c The lower limit of the content of the oil for organic solvent extraction based on the total volume of the mixture of ) may be 0.1 (v / v)% or more, 0.2 (v / v)% or more, 0.3 (v / v)% or more, 1 (v / v)% or more, 2 (v / v)% or more, 3 (v / v)% or more, 5 (v / v)% or more, and 10 (v / v)% or more based on the total volume, and the upper limit thereof may be 55 (v / v)% or less, 50 (v / v)% or less, 45 (v / v)% or less, 40 (v / v)% or less, 2 (v / v)% or more, 3 (v / v)% or more, and 5 (v / v)% or more. In addition, the content of the oil for organic solvent extraction is a range combining these, for example, the finally mixed continuous phase and the oil for organic solvent extraction (O cThe amount of the mixture may be 0.1 to 55 (v / v)% based on the total volume of the mixture (see Examples and Experimental Example 6). If the oil for organic solvent extraction is included in an amount of less than 0.1 (v / v)%, there may be a problem in that the beneficial effects of using the continuous phase mixture are reduced. In addition, even if the upper limit of 55 (v / v)% described in the above examples is exceeded, microspheres may be formed, but there may be a problem in that the properties deteriorate.

[0172]

[0173] In the production method according to the present invention, the time at which the oil (Oc) for organic solvent extraction is added in step (b-2) or (b-3) may be at least one of the following time points 1 to 3, but is not limited thereto.

[0174] (Time 1) A time point prior to the emulsion of step (a) being supplied to the microsphere manufacturing tank;

[0175] (Time 2) A time point at which the emulsion of step (a) is supplied to the microsphere manufacturing tank;

[0176] (Time 3) Time after the emulsion of step (a) has been supplied to the microsphere manufacturing tank.

[0177]

[0178] At the above (time point 1), as shown in FIG. 1 or 2, the oil for organic solvent extraction (Oc) can be supplied in advance to the microsphere manufacturing tank via path (a) or (b), and then the emulsion of step (a) can be supplied. Additionally, in FIG. 3a or 4a, the oil for organic solvent extraction (Oc) can be supplied to the mixing continuous phase emulsion forming device (9) via path (c), while simultaneously supplying the continuous phase to the surfactant, water, and oil for organic solvent extraction (O c A mixture of ) (emulsified mixed continuous phase (W m-e You can prepare phase)) and supply it to the microsphere manufacturing tank in advance, and then supply the emulsion of step (a).

[0179] At the above (time 2), the oil for organic solvent extraction (Oc) can be supplied to the microsphere manufacturing tank via path (a) or (b) in FIG. 1 or FIG. 2, and at the same time, the emulsion can be supplied. Additionally, the oil for organic solvent extraction (Oc) can be supplied to the mixing continuous phase emulsion forming device (9) via path (c) in FIG. 3a or FIG. 4a, and at the same time, the continuous phase can be supplied to prepare a mixture of emulsified surfactant, water, and oil for organic solvent extraction (Oc), and at the same time, the emulsion solution can be supplied to the microsphere manufacturing tank.

[0180] At the above (time 3), after the emulsion solution has been supplied to the microsphere manufacturing tank, the oil for organic solvent extraction (Oc) can be supplied through path (a) or (b) in FIG. 1 or FIG. 2. Additionally, after the emulsion solution has been supplied to the microsphere manufacturing tank, the oil for organic solvent extraction (Oc) can be supplied to the mixing continuous phase emulsion forming device (9) through path (c) in FIG. 3a or FIG. 4a, while simultaneously supplying the continuous phase to prepare a mixture of emulsified surfactant, water, and oil for organic solvent extraction (Oc), and then supplied to the microsphere manufacturing tank.

[0181]

[0182] In the production method according to the present invention, in step (a), the oil for organic solvent extraction (Oc) is mixed with an aqueous solution containing a surfactant and water, and subsequently, this mixture can be mixed with a dispersed phase. As a specific example, the oil for organic solvent extraction (Oc) is supplied to a mixing continuous phase emulsion forming device (9) through path (e) in FIG. 3b or FIG. 4b, while simultaneously supplying an aqueous solution (Wc phase) containing a surfactant and water to prepare a mixture of emulsified surfactant, water, and oil for organic solvent extraction, and this can be supplied to an emulsion solution forming device (5) to form an emulsion.

[0183]

[0184] The continuous phase containing an organic solvent, water, and a surfactant has the properties of oil and water, respectively, so the extraction efficiency is not high. On the other hand, the organic solvent and the oil for organic solvent extraction (Oc) have high miscibility, which can improve the extraction efficiency. That is, by adding the oil for organic solvent extraction to the continuous phase containing water and a surfactant, the organic solvent extracted in the continuous phase is rapidly absorbed into the oil for organic solvent extraction, thereby continuously maintaining the freshness of the continuous phase. This has the effect of significantly reducing the amount of fresh continuous phase used compared to conventional methods. Furthermore, when compared based on a process of injecting the emulsion and the continuous phase into the microsphere manufacturing tank once and letting it stand, the total amount of emulsion that can be injected into the microsphere manufacturing tank in a single process can be increased compared to conventional methods, thereby improving production volume.

[0185] Generally, the production process for one batch of microspheres (microsphere manufacturing tank), excluding the drying process, takes approximately 1 to 2 days. In conventional methods, microspheres are manufactured by injecting the amount of the continuous phase relative to the dispersed phase at tens to hundreds of times the amount of the organic solvent mixed into the continuous phase in order to lower the residual concentration of the organic solvent mixed into the continuous phase. If the amount of the continuous phase is insufficient in the conventional method, the residual concentration of the organic solvent mixed into the continuous phase increases, making it difficult to extract the organic solvent from the emulsion into the continuous phase, which makes it difficult to form microspheres in an initial soft state from the emulsion.

[0186] In other words, in conventional methods, the amount of continuous phase used is significantly higher than that of the dispersed phase, which limits the amount of dispersed phase that can be fed into a microball manufacturing tank with a limited capacity. If the amount of dispersed phase fed is excessive, a problem may arise in which the defect rate of the microballs produced increases. Given that most of the major components of microballs are contained in the dispersed phase, the amount of dispersed phase that can be injected into one batch of a microball manufacturing tank is directly proportional to the production volume of microballs.

[0187]

[0188] The present invention allows the organic solvent extracted in the continuous phase to be rapidly absorbed into the oil for organic solvent extraction in the mixed continuous phase, thereby continuously maintaining the freshness of the continuous phase. Since this significantly reduces the amount of fresh continuous phase used compared to conventional methods, the amount of dispersed phase that can be additionally injected can be increased, which in turn leads to an increase in production volume.

[0189] As shown in Fig. 5, which is merely an example but illustrates a comparison of the amount of dispersed phase that can be injected into a microsphere manufacturing tank in a conventional production method and the production method of the present invention, in the conventional microsphere production method, 350 parts by volume of continuous phase are used relative to 1 part by volume of dispersed phase to manufacture microspheres, whereas in the microsphere production method according to the present invention, 2 parts by volume of organic solvent extraction oil are used relative to 1 part by volume of dispersed phase, so the volume of the continuous phase can be used at 50 parts by volume, which is significantly reduced.

[0190] According to one embodiment, compared to the amount of continuous phase used in a conventional production method (Comparative Examples 1-2), in the present invention (Example 1), even if the amount of continuous phase used is reduced to about one-third, not only is a low level of residual organic solvent concentration in the microspheres achieved, but the characteristics of the microspheres can also be good (see Experimental Example 2).

[0191] In the above steps (b-1), (b-2), or (b-3), a single process of extracting the organic solvent of the dispersed phase toward the initially supplied mixed continuous phase (continuous phase containing oil for organic solvent extraction), i.e., a 'settling process' without a fresh continuous phase substitution process, can be carried out.

[0192] As another example, in step (b-1), (b-2), or (b-3), a fresh continuous phase may be additionally injected while extracting the organic solvent in the dispersed phase into the continuous phase. For example, a 'substitution process' may be performed to discharge the continuous phase mixed with the organic solvent and supply a fresh continuous phase. The substitution process may be performed as a discontinuous process and may be carried out in multiple steps. As yet another example, a 'continuous process' may be performed to discharge the continuous phase mixed with the organic solvent and simultaneously supply a fresh continuous phase.

[0193] When using the above 'substitution process' or 'continuous process', the efficiency of removing the dispersed phase organic solvent in the emulsion can be further increased.

[0194] When using the above 'stationary process' and 'substitution process', the amount of emulsion that can be supplied to the microsphere manufacturing tank is injected once, and then microspheres can be produced through step (b-1), step (b-2) or step (b-3).

[0195] When using the above 'continuous process', microspheres can be produced through step (b-1), step (b-2) or step (b-3) while continuously injecting an amount of emulsion that can be supplied to the microsphere manufacturing tank.

[0196]

[0197] The above "continuous phase mixed with organic solvent" refers to a state in which an organic solvent is mixed into the continuous phase as the dispersed phase organic solvent within the emulsion is extracted from the microsphere manufacturing tank toward the continuous phase. Here, since the organic solvent evaporation is selectively carried out through heating in the continuous phase mixed with organic solvent, the organic solvent may remain in the continuous phase mixed with organic solvent at a concentration of only a portion or trace amount, or it may be a state in which all of the organic solvent has evaporated.

[0198]

[0199] In addition, the organic solvent mixed with the continuous phase can be recycled by separating the organic solvent, the oil for organic solvent extraction, and the continuous phase, respectively. Adding a recycling process is significant in that it enables the production of microspheres using an environment-friendly process. Any known technology can be used to separate the organic solvent. For example, organic solvent evaporation-condensation recovery, OSRO (Organic solvent reverse osmosis), OSN (organic solvent nanofiltration), SRNF (solvent-resistant nanofiltration), etc., can be used.

[0200]

[0201] In the production method according to the present invention, step (b-1), (b-2), or (b-3) may further include a heat treatment for the evaporation of an organic solvent. When heating the continuous phase in steps (b-1), (b-2), and (b-3), the temperature is not particularly limited, but it may be heated to a level close to the boiling point of the organic solvent used to prepare the dispersed phase, or it may be used at room temperature without heating. If heated to a level close to the boiling point of the organic solvent, it may be advantageous for the selective evaporation of the organic solvent mixed into the continuous phase after the organic solvent of the dispersed phase is extracted from the emulsion suspended in the continuous phase. If the drug used is a drug sensitive to high temperatures, it may be heated to a level that does not affect the activity of the drug. Additionally, the continuous phase may be prepared at room temperature and heated in a microsphere manufacturing tank.

[0202]

[0203] The production method of the present invention may further include the step of drying the microspheres produced by the above-described method and filling them into a container.

[0204] Accordingly, an additional aspect of the present invention relates to a method for manufacturing dried microspheres and / or a method for manufacturing an injectable composition comprising dried microspheres.

[0205] In one example, the above manufacturing method may include the step of drying the microspheres produced by the above microsphere production method and then filling the dried microspheres into a container.

[0206] In one example, the above manufacturing method may include the step of washing the microspheres produced by the above microsphere production method to remove a surfactant remaining on the surface of the microspheres; the step of recovering the microspheres and drying the recovered microspheres; and the step of filling the dried microspheres into a container.

[0207] As a specific example, after the above steps (b-1), (b-2), or (b-3), the entire continuous phase mixed with the organic solvent may be discharged, and then the following steps (d-1) to (g-1) may be further included to fill the dried microspheres into a container. Here, the following step (f-1) is a drying process and is included in the conventional biodegradable microsphere production process.

[0208] (d-1) A step of removing residual surfactant from the surface of microspheres through washing;

[0209] (e-1) Step of recovering microspheres;

[0210] (f-1) A step of drying the obtained microspheres; and

[0211] (g-1) Step of filling a container with dried microspheres.

[0212]

[0213] In addition, between step (d-1) and step (e-1), a sieving process can be additionally used to obtain uniform microspheres. The sieving process can be performed using known technology, and microspheres of uniform size can be obtained by filtering out small and large particles using sieves of different sizes.

[0214] Step (d-1) above may use various known techniques, for example, washing with water, and the washing may be repeated one to several times.

[0215] Step (e-1) above may utilize various known techniques, and microspheres may be recovered using methods such as filtration or centrifugation, for example. For example, microspheres may be recovered using a hydrocyclone method utilizing centrifugation, a tangential flow filtration (TFF) method having a porous filter structure, and / or a method of connecting a hydrocyclone and a TFF in series.

[0216] The above step (f-1) may use various known techniques, and microspheres may be dried using methods such as freeze-drying, vacuum freeze-drying, low-temperature drying, room-temperature drying, hot air drying, ventilation drying, pressurized-decreased-pressure drying, fluidized bed drying, vacuum drying, infrared drying, suction drying, etc.

[0217] A final product can be obtained by filling the dried microspheres from step (g-1) into a suitable container. For example, a final product can be obtained by filling the dried microspheres into a container such as a syringe, cartridge, or vial.

[0218]

[0219] The production method of the present invention may further include the step of suspending microspheres produced by the above-described method in a non-aqueous vehicle and filling them into a container.

[0220] Accordingly, an additional aspect of the present invention relates to a method for preparing microspheres suspended in a non-aqueous vehicle and / or a method for preparing an injectable composition comprising microspheres suspended in a non-aqueous vehicle.

[0221] In one example, the method for preparing microspheres suspended in a non-aqueous vehicle and / or the method for preparing an injectable composition comprising microspheres suspended in a non-aqueous vehicle may include, after step (b-1), (b-2) or (b-3), a step of performing an aggregation reduction treatment on the obtained microspheres after partially or entirely discharging a mixed continuous phase mixed with an organic solvent.

[0222]

[0223] In one example, to produce microspheres suspended in a non-aqueous vehicle, first, after steps (b-1), (b-2), or (b-3), a mixed continuous phase mixed with an organic solvent may be discharged in part or in whole, and then a coagulation reduction treatment may be performed by further including step (c-1) alone; sequentially performing steps (c-1) and (c-2); or step (c-3) alone. Here, assuming the volume of the mixed continuous phase mixed with an organic solvent is 100 parts by volume, the term 'part' may be 1 to 99 parts by volume. By using this process, expensive aseptic drying facilities can be omitted from the manufacturing facility, thereby significantly reducing facility and operating costs.

[0224] (c-1) A step of treating with a microparticle aggregation reduction treatment solution (treatment solution A) containing an oil (Oc) for organic solvent extraction and a surfactant;

[0225] (c-2) A step of treating with a microparticle aggregation reduction treatment solution (treatment solution B) comprising an oil (Oc) for organic solvent extraction and a water-miscible solvent;

[0226] (c-3) A step of treating with a microsphere aggregation reduction treatment solution (treatment solution C) comprising an oil for organic solvent extraction (Oc), a surfactant, and a water-miscible solvent.

[0227] The surfactants used in steps (c-1) and (c-3) above may independently use one or more types selected from a hydrophilic-lipophile balance (HLB) value in the range of 3 to 8, and

[0228] The water-miscible solvent used in steps (c-2) and (c-3) above may independently be one or more selected from the group consisting of methanol, ethanol, propanol, acetone, isopropyl alcohol, cetyl alcohol, and benzyl alcohol.

[0229]

[0230] In the present invention, the “aggregation reduction treatment” is a step performed for the purpose of reducing (reducing) or removing residual moisture within the microspheres obtained in step (b-1), (b-2), or (b-3) in order to consequently suppress (prevent, reduce, or reduce) aggregation within the non-aqueous vehicle.

[0231] In a specific embodiment, the “step of treating with a micro-particle aggregation reduction treatment solution” in (c-1), (c-2), and (c-3) above may be performed by adding the micro-particles obtained in step (b-1) or (b-2) to the micro-particle aggregation reduction treatment solution and stirring.

[0232]

[0233] The surfactant used in the above microsphere aggregation reduction treatment solution may have a hydrophilic-lipophile balance (HLB) value in the range of 3 to 8. Here, the HLB value follows the Davis formula, and hydrophilicity increases as the HLB value increases. If the HLB value is less than 3, there may be a problem of phase separation occurring because phase emulsification is difficult in the production method of the present invention which uses a large amount of water, and if it is greater than 8, there may be a problem where an unstable emulsion is generated during the formation of an emulsion to reduce aggregation, or where the microspheres are not redispersed because excessive moisture remains in the surfactant that surrounds the surface of the microspheres, even though it mixes well with water.

[0234] Examples of surfactants corresponding to the HLB value range of 3 to 8 include lecithin, sorbitan, sorbitan triolate, glycol stearate, sorbitan sesquioleate, sorbitan oleate, sorbitan stearate, sorbitan isostearate, brij 72 (manufacturer: Merck), brij 93veg (manufacturer: Croda), Ethylan D252 (manufacturer: Nouryon), ritoleth 2 (manufacturer: Rita Corporation), Volpo S2 (manufacturer: Croda), etc., which can be used alone or in a mixture of two or more.

[0235]

[0236] In one example, the agglomeration reduction treatment solution of step (c-1) above may be a mixture prepared by mixing the surfactant with the agglomeration reduction oil phase at a concentration of 0.1 to 10 (w / v)%, 0.1 to 5 (w / v)%, 0.1 to 1 (w / v)%, 0.5 to 9 (w / v)%, 0.5 to 4 (w / v)%, 0.5 to 3 (w / v)%, 0.5 to 2 (w / v)%, or 0.5 to 1 (w / v)% relative to the volume of the agglomeration reduction oil phase, but is not limited thereto.

[0237] In one example, the above step (c-1) may include the step of stirring the mixture for 1 minute to 120 minutes, 1 minute to 80 minutes, 1 minute to 40 minutes, 10 minutes to 100 minutes, 10 minutes to 60 minutes, 10 minutes to 40 minutes, 20 minutes to 60 minutes, 20 minutes to 40 minutes, or 30 minutes after treating the aggregation-reducing treatment liquid with microspheres.

[0238] Here, the stirring may be performed at a speed of 50 to 1,000 rpm, 50 to 700 rpm, 50 to 500 rpm, 100 to 800 rpm, 100 to 500 rpm, 200 to 600 rpm, 300 to 500 rpm, 300 to 400 rpm, or 400 rpm, but is not limited thereto.

[0239] In one example, when the above steps (c-1) and (c-2) are performed sequentially, the above step (c-2) may be performed after the entire mixture containing the coagulation reduction treatment liquid of the above step (c-1) has been filtered.

[0240] In one example, the agglomeration reduction treatment liquid of step (c-2) above may be a mixture prepared by mixing an oil phase for agglomeration reduction and a water-miscible solvent in a volume ratio of 1 to 30:1, 1 to 15:1, 5 to 20:1, 5 to 10:1, 7 to 15:1, 8 to 10:1, or 9:1, but is not limited thereto. In one example, the above step (c-2) may include the step of stirring the mixture for 1 minute to 120 minutes, 1 minute to 80 minutes, 1 minute to 40 minutes, 10 minutes to 100 minutes, 10 minutes to 60 minutes, 10 minutes to 40 minutes, 20 minutes to 60 minutes, 20 minutes to 40 minutes, or 30 minutes after treating the aggregation-reducing treatment liquid with microspheres.

[0241] Here, the stirring may be performed at a speed of 50 to 1,000 rpm, 50 to 700 rpm, 50 to 500 rpm, 100 to 800 rpm, 100 to 500 rpm, 200 to 600 rpm, 300 to 500 rpm, 300 to 400 rpm, or 400 rpm, but is not limited thereto.

[0242] In one example, the agglomeration reduction treatment solution of step (c-3) above comprises: (i) a mixed solvent in which an oil phase for agglomeration reduction and a water-miscible solvent are mixed in a volume ratio of the oil phase for agglomeration reduction to the water-miscible solvent of 1 to 30:1, 1 to 15:1, 5 to 20:1, 5 to 10:1, 7 to 15:1, 8 to 10:1, or 9:1, and (ii) a surfactant in an amount of 0.1 to 10(w / v)%, 0.1 to 5(w / v)%, 0.1 to 1(w / v)%, 0.5 to 9(w / v)%, 0.5 to 4(w / v)%, 0.5 to 3(w / v)%, 0.5 to 2(w / v)%, or 0.5 to 10(w / v)%, relative to the final volume of the mixed solvent. It may be prepared by mixing at a concentration of 1 (w / v)%, but is not limited thereto. However, the order of the above processes (i) and (ii) is not particularly limited, and a surfactant may be mixed first into the oil phase for reducing coagulation, followed by additional mixing of a water-miscible solvent, or a surfactant may be mixed into the water-miscible solvent, followed by additional mixing of the oil phase for reducing coagulation.

[0243] In one example, the above step (c-3) may include the step of stirring the mixture for 1 minute to 120 minutes, 1 minute to 80 minutes, 1 minute to 40 minutes, 10 minutes to 100 minutes, 10 minutes to 60 minutes, 10 minutes to 40 minutes, 20 minutes to 60 minutes, 20 minutes to 40 minutes, or 30 minutes after treating the aggregation-reducing treatment liquid with microspheres.

[0244] Here, the stirring may be performed at a speed of 50 to 1,000 rpm, 50 to 700 rpm, 50 to 500 rpm, 100 to 800 rpm, 100 to 500 rpm, 200 to 600 rpm, 300 to 500 rpm, 300 to 400 rpm, or 400 rpm, but is not limited thereto.

[0245]

[0246] In one example, the above manufacturing method may include the step of suspending microspheres produced by the above microsphere production method in a non-aqueous vehicle; and the step of filling the non-aqueous vehicle in which the microspheres are suspended into a container.

[0247] In one example, the above manufacturing method may include the step of transferring microspheres produced by the above microsphere production method to a storage tank for a main composition; the step of injecting a non-aqueous vehicle into the storage tank for a main composition to prepare a non-aqueous vehicle in which microspheres are suspended; and the step of filling the non-aqueous vehicle in which microspheres are suspended into a container.

[0248]

[0249] In one example, step (c-1) may be performed alone; steps (c-1) and (c-2) may be performed sequentially; or step (c-3) may be performed alone, and then steps (d-2) to (e-2) below may be further included to fill a non-aqueous vehicle in which microspheres are suspended into a container. By using this process, expensive 'aseptic moisture drying' facilities can be omitted from the manufacturing facility, thereby significantly reducing facility and operating costs.

[0250] (d-2) Step of suspending microspheres in a non-aqueous vehicle; and

[0251] (e-2) A step of filling a container with a non-aqueous vehicle in which the above-mentioned microspheres are suspended.

[0252]

[0253] In one example, step (c-1) may be carried out alone; steps (c-1) and (c-2) may be carried out sequentially; or step (c-3) may be carried out alone, and then steps (d-3) to (f-3) below may be further included to fill a non-aqueous vehicle in which microspheres are suspended into a container. By using this process, expensive 'aseptic moisture drying' facilities can be omitted from the manufacturing facility, thereby significantly reducing facility and operating costs.

[0254] (d-3) A step of transferring microspheres to a storage tank for the main composition;

[0255] (e-3) a step of preparing a non-aqueous vehicle in which microspheres are suspended by injecting the non-aqueous vehicle into a storage tank of the main composition; and

[0256] (f-3) A step of filling a container with a non-aqueous vehicle in which the above-mentioned microspheres are suspended.

[0257]

[0258] Steps (e-2) and (f-3) above may yield a final product in the form of a non-aqueous vehicle in which microparticles are suspended, filled into a suitable container. For example, a final product in a ready-to-use form may be obtained by filling a non-aqueous vehicle (injectable composition) in which microparticles are suspended into a container such as a pre-filled syringe, cartridge, or vial.

[0259]

[0260] The term "sterile moisture drying" in the present invention refers to a process conventionally performed for the purpose of securing the physical properties of microspheres by lowering the residual moisture content within the final microspheres to a standard value or lower (e.g., 5, 4, 3, 2, or 1 weight percent or less relative to the total weight of the microspheres), and refers to the final moisture drying process and powdering process of the microspheres. Specifically, the sterile moisture drying is a drying (powdering) process of microspheres designed to maintain the sterility of the product while removing residual moisture from the microspheres to ensure long-term storage stability of the product before suspending the manufactured microspheres in an injectable non-aqueous vehicle and filling them into a container such as a syringe. Microspheres that have not undergone the sterile moisture drying in a conventional microsphere production process (i.e., a production process that does not include the aggregation reduction treatment step of the present invention) may have a residual moisture content within the microspheres exceeding a standard value or may cause aggregation in the non-aqueous vehicle.

[0261] The term "simple drying" in the present invention refers to an auxiliary drying process performed for the convenience of transporting microspheres or for process operation during, after, and / or before (e.g., after filtration and before input to the next step) each step of the production method according to the present invention (e.g., one or more of steps (a), (b-1), (b-2), (b-3), (c-1), (c-2), (c-3), (d-1), (d-2), (d-3), (c-1), (c-2), (c-3), (f-1), and (f-3). This "simple drying" is clearly distinguished from "aseptic moisture drying," which is intended to remove residual moisture within the final microspheres to a level below a reference value, in terms of its purpose, execution time, and degree of drying.

[0262]

[0263] In one example, the production method according to the present invention may optionally further include a step of performing 'simple drying' during, after, and / or before one or more steps included in the overall process of manufacturing microspheres (e.g., one or more of steps (a), (b-1), (b-2), (b-3), (c-1), (c-2), (c-3), (d-1), (d-2), (d-3), (f-1), and (f-3)), suspending the manufactured microspheres in a non-aqueous vehicle, and filling the manufactured microspheres into a packaging material.

[0264]

[0265] In the production method according to the present invention, the 'non-aqueous vehicle' refers to a pharmaceutically acceptable non-aqueous liquid substance. The vehicle may be substantially inert so as not to interact with the microspheres of the present invention and non-toxic so as not to have an adverse effect on the patient. Specifically, the non-aqueous vehicle used in the present invention does not solubilize the microspheres to an extent that it negatively affects the stability of the microspheres or results in a proven loss of control over burst release.

[0266] The term "vehicle" may include one or more compounds. The vehicle is a non-solubilizing vehicle in that it does not solubilize the biodegradable polymer forming the microspheres. Additionally, the vehicle does not solubilize the active pharmaceutical component within the microspheres.

[0267] The term "non-aqueous" does not exclude trace amounts of residual water that do not have a proven adverse effect on the stability of the sustained-release composition. Thus, the composition may contain less than about 0.25% (w / v) of water, but is still considered non-aqueous. In one embodiment, the vehicle does not enter or permeate the biodegradable polymer and is not dispersed within the biodegradable polymer. The vehicle also does not cause swelling of the microspheres to an extent that has a proven adverse effect on the stability of the microspheres. For example, swelling may occur to an extent of less than 1%.

[0268] In one embodiment, the non-aqueous vehicle is a pharmaceutically acceptable oil. An oil is a substance that is in a viscous liquid state at room temperature or slightly warm temperature and has hydrophobic (immiscible with water) and lipophilic (miscible with other oils) properties. Exemplary pharmaceutically acceptable oil vehicles include vegetable oils and volatile essential oils.

[0269] Specific examples include one or more fractionated oils, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid triglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid diglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acid monoglycerides, one or more C6-C 18 (Specifically, C6-C 12 ) fatty acids, ethyl oleate, one or more propylene glycol C6-C 18(Specifically, C6-C 12 ) Fatty acid diesters, etc., may be used alone or in a mixture of two or more types. For example, one or more medium-chain fatty acids (C6-C 12 ) Triglycerides may be used. Here, the three or two fatty acid chains contained in the triglyceride or diglyceride, respectively, may be the same or different.

[0270] The above medium-chain fatty acid (C6-C 12 ) Triglycerides can be manufactured by methods known in the art, and MIGLYOL ® 810, 812, 812N, 818, 829 (Sasol Germany GmbH, Witten, Germany) or NEOBEE ® It is sold as 1053, 895, M-5 (Stepan Company, Northfield, Il.).

[0271] The above propylene glycol C6-C 18 (Specifically, C6-C 12 ) Fatty acid diesters can be prepared by methods known in the art, and MIGLYOL ® It is marketed as 840 (Sasol Germany GmbH, Witten, Germany).

[0272] The above fractionated oil may be used alone or in a mixture of two or more types, such as coconut oil, palm oil, palm kernel oil, sesame oil, soybean oil, almond oil, rapeseed oil, corn oil, sunflower oil, peanut oil, olive oil, castor oil, soybean oil, safflower oil, and cottonseed oil.

[0273] The above 'non-aqueous vehicle' is injectable and may be of the same or different type as the oil (Oc) used for organic solvent extraction in step (b-1) or (b-2).

[0274] The above-mentioned non-aqueous vehicle may optionally include other pharmaceutically acceptable excipients. Examples of representative excipients include sugars (e.g., sucrose, glucose, dextrose, galactose, maltose, trehalose, fructose, maltodextrin); sugar alcohols (e.g., glycol, glycerol, erythritol, threitol, arabitol, ribitol, sorbitol, dulcitol, iditol, isomalt, maltitol, lactitol, mannitol, xylitol); preservatives (e.g., benzoic acid, sorbic acid, metacresol, sodium benzoate, potassium sorbate, methylparaben, propylparaben, butylparaben, benzalkonium chloride, etc. are generally oil-soluble and have some solubility in selected carriers); Antioxidants (e.g., sodium metabisulfite, butylated hydroxyanisole, butylated hydroxytoluene, sodium sulfite, tocopherol, thymol, ascorbate, propyl gallate, etc.) may be used.

[0275] The above-mentioned non-aqueous vehicle may include a gel-forming agent. However, the gel-forming agent may be present only in an amount that does not cause a gel-depot to form at the site of administration of the formulation in vivo. In one embodiment, the above-mentioned non-aqueous vehicle does not include a gel-forming agent. Exemplary gel-forming agents include cellulose derivatives. Examples include hydroxypropyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, methylcellulose; polyoxyethylene and polyoxypropylene polymers or copolymers (poloxamers); chitosan, etc.

[0276]

[0277] In an additional example, the continuous phase of step (a) or the mixture of the continuous phase and the oil for organic solvent extraction may further include an early release inhibitor for the purpose of inhibiting the early release of the drug. In an example, the early release inhibitor may be included in the fresh continuous phase additionally supplied in step (b-1), step (b-2), or step (b-3).

[0278]

[0279] Specifically, the above-mentioned initial release inhibitor may be a phosphate salt, hydroxide salt, phosphide salt, phosphite salt, carbonate salt, bicarbonate salt, chromate salt, dichromate salt, oxide, oxalate salt, silicate salt, sulfate salt, sulfide salt, sulfite salt, tartrate salt, tetraborate salt, thiosulfate salt, arsenate salt, arsenite salt, citrate salt, ferricyanide salt, nitride salt, etc., of an alkali metal, alkaline earth metal, or ammonium, used alone or in a mixture of two or more. More specifically, the above-mentioned initial release inhibitor may be used alone or in a mixture of two or more types, such as monosodium phosphate (NaH2PO4), disodium phosphate (Na2HPO4), monopotassium phosphate (KH2PO4), dipotassium phosphate (K2HPO4), diammonium phosphate ((NH4)2HPO4), sodium bicarbonate (NaHCO3), sodium carbonate (Na2CO3), and diammonium sulfate ((NH4)2SO4).

[0280]

[0281] In the above continuous phase, the lower limit of the final concentration of the initial release inhibitor may be 0.1 (w / v)% or more, 0.2 (w / v)% or more, 0.3 (w / v)% or more, 0.4 (w / v)% or more, 0.5 (w / v)% or more, 0.6 (w / v)% or more, 0.7 (w / v)% or more, 0.8 (w / v)% or more, 0.9 (w / v)% or more, 1.0 (w / v)% or more, 1.2 (w / v)% or more, 1.4 (w / v)% or more, 1.6 (w / v)% or more, 1.8 (w / v)% or more, or 2.0 (w / v)% or more, and the upper limit may be 10.0 (w / v)% or less, 9.0 (w / v)% or less, 8.0 (w / v)% or less, 7.0 (w / v)% or less, 6.0 (w / v)% or less, 5.0 (w / v)% or less, 4.5 (w / v)% or less, 4.0 (w / v)% or less, 3.5 (w / v)% or less, 3.4 (w / v)% or less, 3.3 (w / v)% or less, 3.2 (w / v)% or less, 3.1 (w / v)% or less, 3.0 (w / v)% or less, 2.9 (w / v)% or less, 2.8 (w / v)% or less, 2.7 (w / v)% or less, 2.6 (w / v)% or less, 2.5 (w / v)% or less, 2.4 (w / v)% or less, 2.3 (w / v)% or less, 2.2 (w / v)% or less, or 2.1 (w / v)% or less, and the initial emission in the continuous phase The final concentration of the inhibitor can be used as a combination of the lower and upper limits described above. For example, 0.1 to 10.0 (w / v)%, 0.1 to 9.0 (w / v)%, 0.1 to 8.0 (w / v)%, 0.1 to 7.0 (w / v)%, 0.1 to 6.0 (w / v)%, 0.1 to 5.0 (w / v)%, 0.2 to 10.0 (w / v)%, 0.2 to 9.0 (w / v)%, 0.2 to 8.0 (w / v)%, 0.2 to 7.0 (w / v)%, 0.2 to 6.0 (w / v)%, 0.2 to 5.0 (w / v)%, 0.3 to 10.0 (w / v)%, 0.3 to 9.0 (w / v)%, 0.3 to 8.0 (w / v)%, 0.3 to 7.0 (w / v)%, 0.3 to 6.It may be 0 (w / v)%, 0.3 to 5.0 (w / v)%, 0.4 to 10.0 (w / v)%, 0.4 to 9.0 (w / v)%, 0.4 to 8.0 (w / v)%, 0.4 to 7.0 (w / v)%, 0.4 to 6.0 (w / v)%, 0.4 to 5.0 (w / v)%, 0.5 to 10.0 (w / v)%, 0.5 to 9.0 (w / v)%, 0.5 to 8.0 (w / v)%, 0.5 to 7.0 (w / v)%, 0.5 to 6.0 (w / v)%, or 0.5 to 5.0 (w / v)%.

[0282] The concentration range of the above-mentioned early-release inhibitor can be used in various ranges by considering manufacturing conditions such as the type of drug, drug release characteristics, manufacturing process, and type of polymer. In this regard, if the upper limit of the concentration range of the above-mentioned early-release inhibitor is exceeded, there may be a problem where the emulsion droplet bursts during the manufacturing process and fails to form microspheres, and if it is below the lower limit, no significant effect on early-release inhibition is observed.

[0283]

[0284] The above initial release inhibitor is in the continuous phase (W in step (a) above. c The initial release inhibitor may be added at the time when the aqueous solution is prepared as a phase, and may also be added at any time while the emulsion, aqueous solution, and / or oil for organic solvent extraction is supplied to the microsphere manufacturing tank in steps (b-1), (b-2), or (b-3), and the timing and method of addition are not limited.

[0285]

[0286] In an additional example, a tangential flow filtration device may be used in the method for manufacturing microspheres according to the present invention.

[0287] The “Tangential flow filtration (TFF)” used in the present invention refers to a device that performs filtration by allowing a substance to be treated to flow in a direction parallel to the surface of a filtration membrane. Unlike a method in which the filtrate passes vertically through the membrane, this tangential flow filtration device is a high-efficiency filtration system that maximizes filtration efficiency by minimizing fouling and clogging on the membrane surface.

[0288] In the method for manufacturing microspheres according to the present invention, when a tangential flow filtration device is used, as shown in FIGS. 2 and 4, various types of membranes may be provided in the tangential flow filtration (TFF) device depending on the purpose of use. Through these membranes, the effect of reducing organic solvents contained in the emulsion solution can be expected. For example, if a general-purpose filtration membrane is provided, a mixed continuous phase containing organic solvents may be partially discharged. As another example, if the organic solvent selective permeable membrane described above is provided, only organic solvents may be selectively partially discharged.

[0289] For example, the tangential flow filtration (TFF) device (6) may be connected to one side of the piping connecting the emulsion solution forming device (5) and the microsphere manufacturing tank (see FIG. 2 or FIG. 4). In this case, some of the organic solvent may be reduced while the emulsion solution is being transferred from the emulsion solution forming device to the microsphere manufacturing tank.

[0290] In another example, the tangential flow filtration (TFF) device (7) is connected to one side of a pipe configured to circulate through a microsphere manufacturing tank, so that the solution passing through the tangential flow filtration device (7) can be recovered back into the microsphere manufacturing tank (see FIG. 2 or FIG. 4). In this case, a portion of the organic solvent can be reduced while the mixed continuous phase mixed with the organic solvent circulates through the tangential flow filtration device (7).

[0291]

[0292] Additionally, as shown in FIGS. 1 to 4 of the present invention,

[0293] When preparing the dispersed phase of the W / O / W method, for example, the first phase (W d phase) and oil phase (O d By supplying the phase) to a separate emulsion forming device, W d / O d Forms an emulsion, and the W d / O d The emulsion can be stored in a dispersed phase (DP) storage tank for use.

[0294] As another example, the dispersed phase storage tank is omitted, and the first water phase (W d phase) and oil phase (O d By supplying the phase) to a separate emulsion forming device, W d / O d Forms an emulsion, and the W d / O d Emulsion continuous phase (W c It can also be used by directly supplying it to an emulsion solution forming device (5) that supplies the phase.

[0295] The above 'separate emulsion forming device' may be an inline mixer, a static mixer, etc. FIGS. 1 to 4 of the present invention discloses the use of a dispersed phase storage tank as an example, but as described above, it is also possible to omit the dispersed phase storage tank.

[0296]

[0297] In an additional example, the dispersed phase (DP) storage tanks may be prepared in a single or multiple numbers. For example, when producing one type of biodegradable microsphere, one dispersed phase (DP) storage tank may be used, and when producing two types of biodegradable microspheres simultaneously, two dispersed phase storage tanks may be used. Here, the two types of biodegradable microspheres may be a blend of microspheres containing the same drug but with different types of biodegradable polymers, or a blend of microspheres containing different drugs.

[0298] Furthermore, the dispersed phase storage tank, continuous phase storage tank, and microsphere manufacturing tank used in the present invention can each be connected in parallel in multiple numbers to enable an expanded design for mass production. For example, the dispersed phase and continuous phase used may be the same, but 1 to 3 continuous phase storage tanks, 2 to 3 dispersed phase storage tanks, and 2 to 3 microsphere manufacturing tanks can be connected in parallel simultaneously.

[0299]

[0300] The present invention will be explained in more detail below through the following manufacturing examples. However, the following manufacturing examples are merely illustrative of the present invention, and the scope of the present invention is not limited by the following manufacturing examples.

[0301] [Example]

[0302] <Example 1>

[0303] Microspheres containing a drug and a biodegradable polymer were prepared according to the O / W method, by performing a microsphere formation step using an oil for organic solvent extraction and freeze-drying the microspheres to produce microspheres according to the present invention. Donepezil free base was used as the drug, and polylactide (intrinsic viscosity 0.35-0.45 dL / g, terminal group acid) was used as the polymer.

[0304] Specifically, a dispersed phase was prepared by mixing a biocompatible polymer, donepezil free base as an active ingredient, and pamosan as a release regulator in dichloromethane (DCM), which is a solvent. The dispersed phase was stirred for at least 30 minutes to ensure that the components were sufficiently dissolved in the solvent before use.

[0305] As a continuous phase, a 0.5% (w / v) polyvinyl alcohol (PVA) aqueous solution (viscosity: 4.8–5.8 mPa·s; the PVA concentration in the final continuous phase was 0.5% (v / v)) was prepared.

[0306] Miglyol 812N (Manufacturer: IOI Oleochemical, Malaysia) was prepared as an oil for organic solvent extraction to be mixed with the continuous phase.

[0307] An emulsion was prepared in which the dispersed phase in the form of microdroplets of the dispersed phase was dispersed in the continuous phase by injecting the continuous phase and the dispersed phase simultaneously using an emulsification device (emulsion solution forming device) equipped with a porous membrane with a diameter of 40 μm. 4,000 mL of the continuous phase was used to prepare the emulsion solution (the same applies to Comparative Examples 1-1 to 1-4).

[0308] Miglyol 812N was pre-injected into the microsphere manufacturing tank via a separate pipeline as an oil for organic solvent extraction, and then the emulsion solution was injected into the microsphere manufacturing tank and stirred at a speed of 400 rpm. The temperature of the preparation vessel was maintained at 25°C, and the organic solvent was extracted from the emulsion toward the mixed continuous phase to prepare a microsphere suspension. At this time, after the injection of the emulsion solution was completed, the temperature was maintained at 40-45°C for 4 hours to evaporate and remove the organic solvent from the mixed continuous phase. During the organic solvent extraction and evaporation steps, the continuous phase was additionally supplied to the continuous substitution process. The amount of continuous phase used in Table 1 represents the total amount used throughout the entire process; the remainder, excluding the amount of continuous phase used during emulsion injection, was supplied to the continuous substitution process. The continuous substitution process supplied the additional continuous phase while simultaneously discharging the continuous phase from which the organic solvent had been extracted.

[0309] After the removal of the organic solvent, the temperature of the microsphere suspension was lowered to 25°C, and the residual polyvinyl alcohol was removed by filtration and washing three times with triple distilled water, and donepezil-containing microspheres were prepared by freeze-drying.

[0310]

[0311] <Comparative Example 1-1>

[0312] Donepezil-containing microspheres were prepared by using the O / W method, except that oil for organic solvent extraction was not used, in the same manner as in Example 1 above.

[0313]

[0314] <Comparative Example 1-2>

[0315] Donepezil-containing microspheres were prepared by carrying out the same procedure as in Example 1 above, except that the O / W method was used but no oil for organic solvent extraction was used, and the amount of continuous phase used was increased to 24,000 mL.

[0316]

[0317] <Comparative Examples 1-3 and 1-4>

[0318] Donepezil-containing microspheres were prepared by carrying out the same procedure as in Example 1 above, except that the O / W method was used but no oil for organic solvent extraction was used, the amount of the continuous phase was increased, and the amount of each component in the dispersed phase and the dispersed phase was reduced as shown in Table 1.

[0319]

[0320] The types of polymers, amounts of drugs, etc. used in Example 1 and Comparative Examples 1-1 to 1-4 are summarized and shown in Table 1 below.

[0321]

[0322] a) Amount of dispersed phase (DP) added per 1L of microsphere manufacturing tank (emulsion storage tank) capacity

[0323] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in the preparation of the emulsion is 4,000 mL, and the remainder is supplied to the continuous displacement process.

[0324] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0325] MCT: Miglyol 812N

[0326]

[0327] <Example 2-1>

[0328] The following process was carried out to produce the microspheres of the present invention using the O / W method, an oil for organic solvent extraction, and a microsphere aggregation reduction treatment step (c-1). Two types of poly(lactide-co-glycolide) blends (simple mixtures) (L:G repeating unit molar ratio 65~75 : 35~25, intrinsic viscosity 0.32-0.44 dL / g, terminal group acid) were used as polymers.

[0329] A biocompatible polymer (a blend of the two types of PLGA mentioned above) was mixed with dichloromethane (DCM) and glacial acetic acid (GAA) as solvents to prepare a dispersed phase. The dispersed phase was stirred for at least 30 minutes to sufficiently dissolve the components before use.

[0330] For the continuous phase, a 0.5% (w / v) polyvinyl alcohol (viscosity: 4.8-5.8 mPa·s; the PVA concentration in the final continuous phase was 0.5% (v / v)) aqueous solution was prepared.

[0331] Miglyol 812N (Manufacturer: IOI Oleochemical, Malaysia) was prepared as an oil for organic solvent extraction.

[0332] An emulsion was prepared in which the dispersed phase in the form of microdroplets of the dispersed phase was dispersed in the continuous phase by injecting the continuous phase and the dispersed phase simultaneously using an emulsification device (emulsion solution forming device) equipped with a porous membrane with a diameter of 40 μm. 2,400 mL of the continuous phase was used to prepare the emulsion solution (the same applies to Comparative Examples 2-1 to 2-3 and Examples 2-2 to 2-3).

[0333] Miglyol 812N was pre-injected into the microsphere manufacturing tank via a separate pipeline as an oil for organic solvent extraction. Then, the emulsion solution was injected into the microsphere manufacturing tank and stirred at a speed of 400 rpm, while 68.5 g of disodium phosphate (Na2HPO4) was dissolved and injected into an additional 750 mL of the continuous phase as an initial release inhibitor. The temperature of the preparation container (microsphere manufacturing tank) was maintained at 25°C, and the organic solvent was extracted from the emulsion toward the continuous phase to prepare a microsphere suspension. At this time, after the injection of the emulsion solution was finished, the temperature was maintained at 40-45°C for 4 hours to evaporate and remove the organic solvent from the mixed continuous phase containing the organic solvent. Here, the continuous phase displacement process was not performed.

[0334] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil and lecithin was added as a microsphere aggregation reduction treatment solution (treatment solution A), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-1). The microsphere aggregation reduction treatment (step c-1) was performed three times under the same conditions.

[0335] The placebo microspheres, after the microsphere aggregation reduction treatment was completed, were filtered, and after simple drying (room temperature vacuum drying for 2 minutes) without performing aseptic moisture drying (freeze-drying) of the filtered final microspheres, the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0336]

[0337] <Example 2-2>

[0338] The following process was carried out to produce the microspheres of the present invention using the O / W method and the oil for organic solvent extraction and microsphere aggregation reduction treatment steps (c-1) and (c-2).

[0339] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 2-1 above, except that a free base of semaglutide was additionally added as an active ingredient to the dispersed phase and the microsphere aggregation reduction treatment was changed as follows.

[0340] The dispersed phase was prepared by dissolving a biocompatible polymer (a blend of the two types of PLGA) in dichloromethane (DCM), a solvent, to prepare a polymer solution, then dissolving a free base of semaglutide as an active ingredient in acetic acid, a co-solvent, to prepare a drug solution, and then mixing the polymer solution and the drug solution to prepare the dispersed phase.

[0341] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil and lecithin was added as a microsphere aggregation reduction treatment solution (treatment solution A), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-1). The microsphere aggregation reduction treatment (step c-1) was performed three times under the same conditions.

[0342] Next, a mixture of Miglyol 812N oil and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution B), stirred at 400 rpm for 30 minutes, and then completely filtered (step c-2). The microsphere aggregation reduction treatment (step c-2) was performed three times under the same conditions.

[0343] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0344]

[0345] <Example 2-3>

[0346] The following process was carried out to produce microspheres according to the present invention using the O / W method, an oil for organic solvent extraction, and a microsphere aggregation reduction treatment step (c-3).

[0347] A placebo microsphere (microsphere without drug) was prepared by carrying out the procedure in the same manner as Example 2-1 above, except that the microsphere aggregation reduction treatment was changed as follows.

[0348] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil, lecithin, and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution C), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-3). The microsphere aggregation reduction treatment (step c-3) was performed three times under the same conditions.

[0349] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0350]

[0351] <Comparative Example 2-1>

[0352] The following process was carried out to produce microspheres using the O / W method and organic solvent extraction oil, without performing a microsphere aggregation reduction treatment process and without freeze-drying.

[0353] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 2-1 above, except that a free base of semaglutide was additionally added as an active ingredient to the dispersed phase and the microsphere aggregation reduction treatment was omitted.

[0354] The dispersed phase was prepared by dissolving a biocompatible polymer (a blend of the two types of PLGA) in dichloromethane (DCM), a solvent, to prepare a polymer solution, then dissolving a free base of semaglutide as an active ingredient in acetic acid, a co-solvent, to prepare a drug solution, and then mixing the polymer solution and the drug solution to prepare the dispersed phase.

[0355] After filtering the microspheres prepared above, the final filtered microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0356]

[0357] <Comparative Example 2-2>

[0358] To manufacture microspheres using the O / W method, organic solvent extraction oil, and only the microsphere aggregation reduction treatment process (c-2), the following process was carried out.

[0359] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 2-1 above, except that a free base of semaglutide was additionally added as an active ingredient to the dispersed phase and the microsphere aggregation reduction treatment was changed as follows.

[0360] The dispersed phase was prepared by dissolving a biocompatible polymer (a blend of the two types of PLGA) in dichloromethane (DCM), a solvent, to prepare a polymer solution, then dissolving a free base of semaglutide as an active ingredient in acetic acid, a co-solvent, to prepare a drug solution, and then mixing the polymer solution and the drug solution to prepare the dispersed phase.

[0361] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered to leave approximately 10 (v / v)% of the mixed continuous phase and microspheres. Then, a mixture of Miglyol 812N oil and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution B), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-2). The microsphere aggregation reduction treatment (step c-2) was performed three times under the same conditions.

[0362] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0363]

[0364] <Comparative Example 2-3>

[0365] To manufacture microspheres using the O / W method but without using oil for organic solvent extraction, the following process was carried out.

[0366] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 2-1 above, except that a free base of semaglutide was additionally added as an active ingredient in the dispersed phase, an oil for organic solvent extraction was not used, and the microsphere aggregation reduction treatment was omitted.

[0367] The dispersed phase was prepared by dissolving a biocompatible polymer (a blend of the two types of PLGA) in dichloromethane (DCM), a solvent, to prepare a polymer solution, then dissolving a free base of semaglutide as an active ingredient in acetic acid, a co-solvent, to prepare a drug solution, and then mixing the polymer solution and the drug solution to prepare the dispersed phase.

[0368] After filtering the microspheres prepared above, the final filtered microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0369]

[0370] The types of polymers, amounts of drugs, etc. used in the above Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3 are summarized and shown in Table 2 below.

[0371]

[0372] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used during emulsion preparation is 2,400 mL, and the remaining 750 mL is supplied together with an initial release inhibitor after emulsion injection.

[0373] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0374] MCT: Miglyol 812N

[0375] Step c-1: Mixture of 300 mL Miglyol 812N oil and 2.8 g lecithin

[0376] Step c-2: Mixture of 270 mL Miglyol 812N oil and 30 mL anhydrous ethanol

[0377] Step c-3: Mixture of 270 mL Miglyol 812N oil, 2.8 g lecithin, and 30 mL anhydrous ethanol

[0378]

[0379] <Example 3-1>

[0380] The following process was carried out to produce the microspheres of the present invention using the W / O / W method, an oil for organic solvent extraction, and a microsphere aggregation reduction treatment step (c-1). Two types of poly(lactide-co-glycolide) blends (simple mixtures) (L:G repeating unit molar ratio 65~75 : 35~25, intrinsic viscosity 0.32-0.44 dL / g, terminal group acid) were used as polymers.

[0381] As a drug, semaglutide free base is dissolved in distilled water to form a drug solution (W d ) prepare, and dissolve a biocompatible polymer (a blend of the two types of PLGA mentioned above) in dichloromethane (DCM) as a solvent to obtain a polymer solution (O d ) was prepared. The above drug solution (W d ) and polymer solution (O d) was stirred at 25,000 rpm for 5 minutes using an IKA Homozeniger (T 18 digital ultra turrax), and W d / O d An emulsion was prepared as a dispersed phase.

[0382] For the continuous phase, a 0.5% (w / v) polyvinyl alcohol (viscosity: 4.8-5.8 mPa·s; the PVA concentration in the final continuous phase was 0.5% (v / v)) aqueous solution was prepared.

[0383] Miglyol 812N (Manufacturer: IOI Oleochemical, Malaysia) was prepared as an oil for organic solvent extraction.

[0384] An emulsion was prepared in which the dispersed phase in the form of microdroplets of the dispersed phase was dispersed in the continuous phase by injecting the continuous phase and the dispersed phase simultaneously using an emulsification device (emulsion solution forming device) equipped with a porous membrane with a diameter of 40 μm. 2,400 mL of the continuous phase was used to prepare the emulsion solution (the same applies to Comparative Examples 5 to 6 and Examples 6 to 7).

[0385] Miglyol 812N was pre-injected into a microsphere manufacturing tank (preparation container) via a separate pipeline as an oil for organic solvent extraction. Then, the emulsion solution was injected into the microsphere manufacturing tank and stirred at a speed of 400 rpm, while 68.5 g of disodium phosphate (Na2HPO4) was dissolved and injected into an additional 750 mL of the continuous phase as an initial release inhibitor. The temperature of the microsphere manufacturing tank was maintained at 25°C, and the organic solvent was extracted from the emulsion to the continuous phase to prepare a microsphere suspension. At this time, after the injection of the emulsion solution was finished, the temperature was maintained at 40-45°C for 4 hours to evaporate and remove the organic solvent from the mixed continuous phase containing the organic solvent. Here, the continuous phase displacement process was not performed.

[0386] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil and lecithin was added as a microsphere aggregation reduction treatment solution (treatment solution A), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-1). The microsphere aggregation reduction treatment (step c-1) was performed three times under the same conditions.

[0387] The placebo microspheres, after the microsphere aggregation reduction treatment was completed, were filtered, and after simple drying (room temperature vacuum drying for 2 minutes) without performing aseptic moisture drying (freeze-drying) of the filtered final microspheres, the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0388]

[0389] <Example 3-2>

[0390] The following process was carried out to produce the microspheres of the present invention using the W / O / W method and the oil for organic solvent extraction and microsphere aggregation reduction treatment steps (c-1) and (c-2).

[0391] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 3-1 above, except that the microsphere aggregation reduction treatment was changed as follows.

[0392] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil and lecithin was added as a microsphere aggregation reduction treatment solution (treatment solution A), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-1). The microsphere aggregation reduction treatment (step c-1) was performed three times under the same conditions.

[0393] Next, a mixture of Miglyol 812N oil and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution B), stirred at 400 rpm for 30 minutes, and then completely filtered (step c-2). The microsphere aggregation reduction treatment (step c-2) was performed three times under the same conditions.

[0394] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0395]

[0396] <Example 3-3>

[0397] The following process was carried out to produce microspheres according to the present invention using the W / O / W method, an oil for organic solvent extraction, and a microsphere aggregation reduction treatment step (c-3).

[0398] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 3-1 above, except that the microsphere aggregation reduction treatment was changed as follows.

[0399] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered. With approximately 10 (v / v)% of the mixed continuous phase and microspheres remaining, a mixture of Miglyol 812N oil, lecithin, and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution C), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-3). The microsphere aggregation reduction treatment (step c-3) was performed three times under the same conditions.

[0400] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0401]

[0402] <Comparative Example 3-1>

[0403] The following process was carried out to produce microspheres using the W / O / W method and organic solvent extraction oil, without performing a microsphere aggregation reduction treatment process and without freeze-drying.

[0404] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 3-1 above, except that the microsphere aggregation reduction treatment was omitted.

[0405] After filtering the microspheres prepared above, the final filtered microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0406]

[0407] <Comparative Example 3-2>

[0408] To manufacture microspheres using the W / O / W method, organic solvent extraction oil, and only the microsphere aggregation reduction treatment process (c-2), the following process was carried out.

[0409] Semaglutide-containing microspheres were prepared by carrying out the same procedure as in Example 3-1 above, except that the microsphere aggregation reduction treatment was changed as follows.

[0410] After the removal of the organic solvent was completed, the temperature of the microsphere suspension was lowered to 25°C, and the microsphere suspension was filtered to leave approximately 10 (v / v)% of the mixed continuous phase and microspheres. Then, a mixture of Miglyol 812N oil and anhydrous ethanol was added as a microsphere aggregation reduction treatment solution (treatment solution B), stirred at 400 rpm for 30 minutes, and then the entire solution was filtered (step c-2). The microsphere aggregation reduction treatment (step c-2) was performed three times under the same conditions.

[0411] After all of the above microsphere aggregation reduction treatment steps were completed, the filtered final microspheres were not subjected to aseptic moisture drying (freeze-drying) but were subjected to simple drying (room temperature vacuum drying for 2 minutes), after which the microspheres were suspended in Miglyol 812N oil as a non-aqueous vehicle and stored.

[0412]

[0413] The types of polymers, amounts of drugs, etc. used in Examples 3-1 to 3-3 and Comparative Examples 3-1 to 3-2 above are summarized and shown in Table 3 below.

[0414]

[0415] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used during emulsion preparation is 2,400 mL, and the remaining 750 mL is supplied together with an initial release inhibitor after emulsion injection.

[0416] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0417] MCT: Miglyol 812N

[0418] Step c-1: Mixture of 300 mL Miglyol 812N oil and 2.8 g lecithin

[0419] Step c-2: Mixture of 270 mL Miglyol 812N oil and 30 mL anhydrous ethanol

[0420] Step c-3: Mixture of 270 mL Miglyol 812N oil, 2.8 g lecithin, and 30 mL anhydrous ethanol

[0421]

[0422] <Examples 4-1 to 4-5 and Comparative Examples 4-1 to 4-2>

[0423] Microspheres containing a drug and a biodegradable polymer were prepared according to the O / W method, and the microsphere formation step was performed using an oil for organic solvent extraction, and microspheres according to the present invention were prepared. Donepezil free base was used as the drug, and polylactide (intrinsic viscosity 0.35-0.45 dL / g, terminal group acid) was used as the polymer.

[0424] Specifically, a dispersed phase was prepared by mixing a biocompatible polymer, donepezil free base as an active ingredient, and pamosan as a release regulator in dichloromethane (DCM), which is a solvent. The dispersed phase was stirred for at least 30 minutes to ensure that the components were sufficiently dissolved in the solvent before use.

[0425] As a mixed continuous phase, 4,000 mL of an aqueous solution of 0.5% (w / v) polyvinyl alcohol (PVA) (viscosity: 4.8–5.8 mPa·s; PVA concentration in the final continuous phase is 0.5% (v / v)) and Miglyol 812N (manufacturer: IOI Oleochemical, Malaysia) as an oil for organic solvent extraction were mixed in the volumes shown in Table 4.

[0426] An emulsion was prepared in which the dispersed phase in the form of microdroplets of the dispersed phase was dispersed in the continuous phase by injecting the mixed continuous phase at the same time using an emulsification device (emulsion solution forming device) equipped with a porous membrane with a diameter of 40 μm.

[0427] The above emulsion solution was injected into an empty microsphere manufacturing tank and stirred at a speed of 400 rpm for 35 minutes. The temperature of the preparation container was maintained at 25℃, and no heat treatment for organic solvent evaporation was performed, nor was a continuous phase displacement process carried out.

[0428] After the above stirring was finished, the filtered soft microspheres were subjected to simple drying (room temperature vacuum drying for 1 minute) and used as the sample for Experimental Example 5.

[0429]

[0430] The types of polymers, amounts of drugs, etc. used in Examples 4-1 to 4-5 and Comparative Examples 4-1 to 4-2 are summarized and shown in Table 4 below.

[0431]

[0432] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in the preparation of the emulsion is 4,000 mL, and no additional use.

[0433] Oil phase: The oil for organic solvent extraction is mixed with the continuous phase during emulsion preparation and is not pre-filled into the microsphere manufacturing tank.

[0434] MCT: Miglyol 812N

[0435]

[0436] <Example 5>

[0437] Microspheres containing a drug and a biodegradable polymer were prepared according to the O / W method, and the microsphere formation step was performed using an oil for organic solvent extraction, and microspheres according to the present invention were prepared. Donepezil free base was used as the drug, and polylactide (intrinsic viscosity 0.35-0.45 dL / g, terminal group acid) was used as the polymer.

[0438] Specifically, a dispersed phase was prepared by mixing a biocompatible polymer, donepezil free base as an active ingredient, and pamosan as a release regulator in dichloromethane (DCM), which is a solvent. The dispersed phase was stirred for at least 30 minutes to ensure that the components were sufficiently dissolved in the solvent before use.

[0439] As the continuous phase, 480 mL of an aqueous solution of 0.5% (w / v) polyvinyl alcohol (PVA) (viscosity: 4.8–5.8 mPa·s; the PVA concentration in the final continuous phase was 0.5% (v / v)) was used.

[0440] An emulsion was prepared in which the dispersed phase in the form of microdroplets of the dispersed phase was dispersed in the continuous phase by injecting the continuous phase at the same time using an emulsification device (emulsion solution forming device) equipped with a porous membrane with a diameter of 40 μm.

[0441] 520 mL of Miglyol 812N (Manufacturer: IOI Oleochemical, Malaysia) was prepared as an oil for organic solvent extraction.

[0442] The above Miglyol 812N was supplied to the microsphere manufacturing tank in advance, and then the above emulsion solution was injected and stirred at a speed of 400 rpm for 10 minutes. The temperature of the preparation container was maintained at 25℃, and no heat treatment for organic solvent evaporation was performed, nor was a continuous phase displacement process carried out.

[0443] After the above stirring was finished, a suspension containing an emulsion and / or soft microspheres in the continuous mixing phase was used as the sample of Experimental Example 6.

[0444]

[0445] The types of polymers, amounts of drugs, and amounts of drugs used in Example 5 above are summarized and shown in Table 5 below.

[0446]

[0447] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in emulsion preparation is 480 mL, and no additional use.

[0448] Oil phase: 520 mL of oil for organic solvent extraction is pre-filled into the microsphere manufacturing tank.

[0449] MCT: Miglyol 812N

[0450]

[0451] <Experimental Example 1> Evaluation of Organic Solvent Absorption and Evaporation of Oils for Organic Solvent Extraction

[0452] The following experiment was conducted to investigate the organic solvent absorption and evaporation efficacy of oils used for organic solvent extraction.

[0453] (1) Absorption evaluation

[0454] The experimental solution was prepared by mixing the dispersed phase, the continuous phase, and the oil for organic solvent extraction, and after stirring for about 40 minutes, stirring was stopped and left to stand. Samples were obtained from the phase-separated oil layer for organic solvent extraction and the continuous phase layer, respectively, and the concentration of dichloromethane (DCM) as the residual organic solvent contained in each layer was analyzed and is shown in Table 6.

[0455] Dispersed phase (containing DCM and 13.5 wt% biodegradable polymer (PURASORB PDL04A): 2 volume ratio

[0456] Continuous phase (containing water and 0.1% (w / v) PVA): 80 volume ratio

[0457] Oil for organic solvent extraction (Miglyol 812N): 1 volume ratio

[0458]

[0459] Sample Residual Organic Solvent (DCM) Concentration (μg / mL) Oil layer for organic solvent extraction 10867 Continuous upper layer 520

[0460] As shown in Table 6, it was confirmed that most of the organic solvent was absorbed into the oil layer for organic solvent extraction, and the freshness of the continuous phase was continuously maintained.

[0461] (2) Evaporation evaluation

[0462] A solution was prepared by mixing 1.5 volumes of organic solvent extraction oil (Miglyol 812N) and 1 volume of organic solvent (DCM), and heating was carried out at 42°C for 3 hours. The concentration of dichloromethane (DCM) as a residual organic solvent contained in the organic solvent extraction oil was analyzed before and after heating, and the results are shown in Table 7.

[0463]

[0464] Sample Residual Organic Solvent (DCM) Concentration (µg / mL) Before Heating 154903 After Heating 12

[0465] As shown in Table 7, it was confirmed that most of the residual organic solvent evaporated from the oil for organic solvent extraction after heating.

[0466] <Experimental Example 2> Evaluation of Continuous Phase Usage Reduction

[0467] (1) Measurement of drug (API) content and encapsulation rate in microspheres

[0468] To measure the drug (API) content of the microspheres prepared in the above examples and comparative examples, 100 mg of microspheres were completely dissolved in 10 mL of dimethyl sulfoxide, and the resulting 100-fold diluted solution was used as the test solution. 20 µl of the diluted solution was injected into an HPLC and analyzed at a detection wavelength of 271 nm. The column used in this measurement was Inertsil ODS-3 (5 µm, 4.6 x 150 mm), and the mobile phase was a mixture of potassium phosphate buffer and acetonitrile.

[0469] 'API content' refers to the weight percentage of the encapsulated drug based on 100 weight% of the manufactured microspheres. 'Encapsulation rate' is expressed as a percentage by dividing the weight percentage of the encapsulated drug based on 100 weight% of the total microspheres by the weight percentage of the drug introduced as raw material. Meanwhile, an encapsulation rate exceeding 100% can be interpreted as occurring due to the loss of the polymer used during the manufacturing process.

[0470]

[0471] (2) Measurement of the initial release rate of a drug on day 1 in vitro

[0472] In this experiment, the occurrence of an 'initial burst' was confirmed by measuring the initial release amount on day 1 of the microspheres prepared in the examples and comparative examples. Specifically, 10 mg of microspheres were placed in 50 mL of a release test solution (sodium phosphate buffer at pH 7.4) and stored at 37°C. After 24 hours, 1 mL of the solution was taken and centrifuged at 15,000 rpm for 10 minutes, after which 20 µL of the supernatant was injected into an HPLC for analysis. The HPLC column and analysis conditions were applied identically to the drug content HPLC analysis conditions described above.

[0473] (3) Method for measuring residual organic solvent (DCM) concentration in microspheres

[0474] The residual organic solvent concentration within the microspheres not only satisfies the standards set by the licensing authority, but a lower concentration is also advantageous for improving the storage stability of the microspheres. An experiment was conducted to determine whether the residual organic solvent concentration within the microspheres meets the DCM licensing standard of less than 600 ppm, even when the amount of continuous phase used is reduced, depending on whether oil for organic solvent extraction is included in the continuous phase. To measure the residual organic solvent concentration in the microspheres, 100 mg of microspheres were taken and mixed with a mixture of 4 mL of N-methylpyrrolidone and 1 mL of water. Analysis was performed by injecting 1 mL of the gas phase using a gas chromatograph (GC) headspace. The column used in this analysis was a DB-624 (0.53 mm x 30 m, 3.0 µm), helium was used as the carrier gas, and the flow rate was set to 5 mL / min and the detector temperature to 250°C.

[0475]

[0476] (4) SEM analysis of the surface characteristics of the microspheres

[0477] Scanning electron microscopy (SEM) observation was performed to analyze the morphological characteristics of the prepared microspheres. 5 mg of microspheres were placed on an aluminum stub attached with carbon tape and platinum coated using an ION-COATER (COXEM, Korea). The aluminum stub was mounted on a scanning electron microscope (COXEM EM-30, Korea), and the morphological characteristics of the microspheres were observed at an acceleration voltage of 10 kV.

[0478]

[0479] The measured drug loading content, encapsulation rate, first-day initial release rate, and residual organic solvent concentration in the microspheres are shown in Table 8 below, and the results of the SEM analysis of the surface characteristics of the microspheres are shown in Figure 6.

[0480]

[0481]

[0482] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in the preparation of the emulsion is 4,000 mL, and the remainder is supplied to the continuous displacement process.

[0483] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0484] MCT: Miglyol 812N

[0485]

[0486] As shown in Table 8,

[0487] In Example 1, by adding an oil for organic solvent extraction to the continuous phase, it was confirmed that the residual organic solvent concentration within the microspheres was approximately 41 ppm, achieving a level below the approval standard of 600 ppm even when the amount of the continuous phase used was reduced. On the other hand, Comparative Example 1-1 was microspheres prepared by carrying out the same procedure as Example 1, except that the oil for organic solvent extraction was not used; it was confirmed that the residual organic solvent concentration within the microspheres was approximately 1079 ppm, exceeding the approval standard of 600 ppm. Next, Comparative Example 1-2 was microspheres prepared by increasing the amount of the general continuous phase instead of using the oil for organic solvent extraction in Example 1; it was confirmed that the residual organic solvent concentration within the microspheres was approximately 27 ppm, achieving a level below the approval standard of 600 ppm.

[0488] In other words, Comparative Examples 1-2 are processes that use only the continuous phase in large quantities, as in the conventional technology. When using only the continuous phase without using oil for organic solvent extraction, only by using it in large quantities can the residual organic solvent concentration within the microspheres be within the permitted limit and the microsphere characteristics appear good. On the other hand, it can be confirmed that Example 1 can be manufactured with a residual organic solvent concentration suitable for the permitted limit even with the amount of continuous phase used reduced by about one-third.

[0489] In addition, looking at the data on drug encapsulation rate and day 1 initial release rate, both Example 1 and Comparative Example 1-2 show good levels, whereas Comparative Example 1-1 is a microsphere prepared by reducing the amount of general continuous phase used, so the residual organic solvent concentration is high, and the day 1 initial release rate is also high at a level exceeding 10%.

[0490]

[0491] Meanwhile, as shown in Fig. 6, it can be confirmed that the surface characteristics of the microspheres do not show a significant difference from those of conventional microspheres using a large amount of general continuous phase, even when an oil for organic solvent extraction is added to the continuous phase.

[0492]

[0493] <Experimental Example 3> Evaluation of Production Volume in a Single Process of Microsphere Production

[0494] In conventional processes that use only a large amount of continuous phase, if the amount of dispersed phase that can be fed in a single process is excessive, a problem may arise where the defect rate of the manufactured microspheres is high, so the amount of dispersed phase that can be fed in a single process is limited. The production volume of microspheres that can be produced in a single process depends on the amount of dispersed phase that can be fed into the microsphere manufacturing tank, but if the freshness of the continuous phase can be continuously maintained even while reducing the amount of continuous phase used, the amount of dispersed phase that can be fed into the microsphere manufacturing tank can be increased.

[0495] This experimental example was conducted to compare the production volume of microspheres that can be produced in a single process when using the production method according to the present invention, which uses an oil for organic solvent extraction mixed in the continuous phase, compared to a production method that uses only a continuous phase as in the past.

[0496]

[0497] The measured drug loading content, encapsulation rate, first-day initial release rate, and residual organic solvent concentration in the microspheres are shown in Table 9 below, and the results of the SEM analysis of the surface characteristics of the microspheres are shown in Figure 7.

[0498]

[0499]

[0500] a) Amount of dispersed phase (DP) added per 1L of microsphere manufacturing tank (emulsion storage tank) capacity

[0501] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in the preparation of the emulsion is 4,000 mL, and the remainder is supplied to the continuous displacement process.

[0502] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0503] MCT: Miglyol 812N

[0504]

[0505] As shown in Table 9,

[0506] In the case of Comparative Example 1-4, which uses a large amount of continuous phase according to a conventional production method, the amount of dispersed phase (DP) input per 1L of microsphere manufacturing tank capacity in a single process must be small, at approximately 6.1 mL / L, to achieve a 'Pass' level where no problems occur with the microsphere characteristics. In addition, in the case of Comparative Example 1-3, the amount of dispersed phase (DP) input per 1L of microsphere manufacturing tank capacity in a single process is 11.4 mL / L, which is approximately 1.86 times the amount compared to Comparative Example 1-4, and the sample produced shows a 'Fail' level for the microsphere characteristics.

[0507] On the other hand, in the case of Example 1, the amount of dispersed phase (DP) added per 1L of microsphere manufacturing tank capacity in a single process is approximately 19.2 mL / L, which is about 3.14 times the level of Comparative Examples 1-4. It can be confirmed that even when the amount is significantly increased, it shows a 'Pass' level where no problems occur with the microsphere characteristics.

[0508] In other words, since the freshness of the continuous phase can be continuously maintained even while reducing the amount of the continuous phase used by mixing and using an oil for organic solvent extraction together with the continuous phase, the amount of dispersed phase that can be added can be increased, which means that the production volume per process can be improved. Specifically, this means that the production volume of microspheres per process can be increased by more than about three times compared to Comparative Examples 1-4, which were manufactured using a conventional method that used only a large amount of the continuous phase.

[0509]

[0510] As shown in Fig. 7,

[0511] It can be confirmed that there is no significant difference between the surface characteristics of the microspheres in Example 1, in which the amount of dispersed phase (DP) input per 1L of microsphere manufacturing tank capacity was significantly increased in a single process by using an oil for organic solvent extraction together with the continuous phase, and the surface characteristics of the microspheres in Comparative Example 1-4, which were manufactured using a conventional method with a large amount of only the continuous phase and a small amount of dispersed phase (DP) input per 1L of microsphere manufacturing tank capacity in a single process. On the other hand, it can be confirmed that the defect rate of the surface characteristics of the microspheres in Comparative Example 1-3, which were manufactured using a conventional method with a large amount of only the continuous phase and a large amount of dispersed phase (DP) input per 1L of microsphere manufacturing tank capacity in a single process, is high.

[0512]

[0513] <Experimental Example 4> Evaluation of Microball Aggregation Occurrence and Microball Moisture Content Depending on Microball Aggregation Reduction Treatment in the Freeze-Drying Omission Process

[0514] Microspheres obtained through a drying process using conventional methods have a low moisture content, so aggregation rarely occurs even when suspended in non-aqueous injectables (oils). On the other hand, if microspheres obtained by omitting the drying process are suspended directly in a non-aqueous injectable, a problem of aggregation may arise. This is because the high moisture content of microspheres obtained by omitting the drying process increases their hydrophilicity, and consequently, when suspended in a non-aqueous injectable, aggregation between the microspheres may occur due to this increased hydrophilicity.

[0515]

[0516] (1) Evaluation of whether microsphere aggregation occurs

[0517] This experimental example was conducted to determine whether aggregation of microspheres occurs depending on whether an aggregation reduction treatment is performed, when microspheres obtained by omitting the drying process are suspended directly in a non-aqueous injectable. Specifically, the aggregation reduction treatment was performed by carrying out step (c-1) alone; step (c-2) alone; sequentially carrying out steps (c-1) and (c-2); or step (c-3) alone.

[0518] (c-1) A step of treating a microparticle aggregation reduction treatment solution containing an oil (Oc) for organic solvent extraction and a surfactant;

[0519] (c-2) A step of treating a microparticle aggregation reduction treatment solution comprising an oil (Oc) for organic solvent extraction and a water-miscible solvent;

[0520] (c-3) A step of treating a microparticle aggregation reduction treatment solution comprising an oil for organic solvent extraction (Oc), a surfactant, and a water-miscible solvent.

[0521] The oil (Oc) used for the above organic solvent extraction was ‘Miglyol 812N’, the surfactant was ‘lecithin’, and the water-miscible solvent was ‘anhydrous ethanol’.

[0522]

[0523] In order to evaluate whether the microspheres prepared in Examples 2 to 4 and Comparative Examples 2 to 4, each having undergone the above-mentioned aggregation reduction treatment, aggregated, they were stored in Miglyol 812N as a non-aqueous vehicle for 1 day and then observed with an optical microscope.

[0524]

[0525] (2) Evaluation of moisture content of microspheres

[0526] This experimental example was conducted to determine the moisture content of microspheres obtained by omitting the drying process of microspheres (conventional aseptic moisture drying process) and reducing aggregation. Specifically, microspheres prepared in Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3 were each recovered by vacuum filtration, and 500 mg of microspheres were taken and subjected to a KF dry oven to measure the moisture content according to the USP 921 analysis method.

[0527]

[0528] The occurrence of microsphere aggregation and moisture content are shown in Table 10 below, and the results of observing the occurrence of microsphere aggregation using an optical microscope are shown in Figure 8.

[0529]

[0530]

[0531]

[0532] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used during emulsion preparation is 2,400 mL, and the remaining 750 mL is supplied together with an initial release inhibitor after emulsion injection.

[0533] Oil phase: Fill the microsphere manufacturing tank with oil for organic solvent extraction before injecting the emulsion.

[0534] MCT: Miglyol 812N

[0535] Step c-1: Mixture of 300 mL Miglyol 812N oil and 2.8 g lecithin

[0536] Step c-2: Mixture of 270 mL Miglyol 812N oil and 30 mL anhydrous ethanol

[0537] Step c-3: Mixture of 270 mL Miglyol 812N oil, 2.8 g lecithin, and 30 mL anhydrous ethanol

[0538]

[0539] As shown in Table 10,

[0540] In the case of Comparative Example 2-1, in which an oil for organic solvent extraction was used along with a continuous phase but no microsphere aggregation reduction treatment was performed, microsphere aggregation occurred and the moisture content was found to be at an excessive level, and

[0541] In the case of Comparative Example 2-2, in which an oil for organic solvent extraction was used along with a continuous phase but Step C-2 was performed alone as a microsphere aggregation reduction treatment, it was found that although the microsphere moisture content was low, microsphere aggregation occurred.

[0542] In Comparative Example 2-3, which used only the continuous phase without oil for organic solvent extraction and did not perform microsphere aggregation reduction treatment, microsphere aggregation did not occur, but the moisture content was found to be excessive.

[0543] On the other hand, in the case of Example 2-1, in which an oil for organic solvent extraction was used along with a continuous phase but step (c-1) was performed alone as a microsphere aggregation reduction treatment, no microsphere aggregation occurred and the moisture content was also found to be at a low level,

[0544] In the case of Example 2-2, in which an oil for organic solvent extraction was used along with a continuous phase and steps (c-1) and (c-2) were sequentially performed as a microsphere aggregation reduction treatment, no microsphere aggregation occurred and the moisture content was also found to be at a low level.

[0545] In the case of Example 2-3, where an oil for organic solvent extraction was used along with a continuous phase, but step (c-3) was performed alone as a microsphere aggregation reduction treatment, no microsphere aggregation occurred and the moisture content was also found to be at a low level.

[0546]

[0547] <Experimental Example 5> Evaluation of Particle Size Uniformity According to Concentration of Organic Solvent Extraction Oil Used in Emulsion Preparation

[0548] In this experimental example, the uniformity of particle size according to the concentration of the organic solvent extraction oil was evaluated when the organic solvent extraction oil is mixed with the continuous phase during the preparation of an emulsion.

[0549] Specifically, as in Examples 4-1 to 4-5 and Comparative Examples 4-1 to 4-2, soft microspheres obtained by stirring for about 35 minutes after the completion of emulsion injection and then performing room temperature vacuum filtration for 1 minute were resuspended in distilled water, and then particle size analysis was performed using a particle size analyzer (manufacturer Anton Paar, model name PSA900) under conditions of ultrasounds for 10 seconds and obscuration of 1% or more, and the Span values ​​were calculated and summarized in Table 11.

[0550] One of the key factors in managing the quality of microspheres is particle size uniformity. The Span value is a well-known indicator of particle size uniformity; a smaller Span value signifies a narrower (more uniform) particle size distribution. Recently, microspheres for long-acting injectables often require a high level of uniformity, typically with a Span value of 1.2 or lower. If the Span value is too large, problems such as an initial burst of drug release after injection and / or clogging when passing through the needle may occur. Conversely, if the Span value is sufficiently small, it becomes easier to predict and control the drug release rate after injection.

[0551]

[0552]

[0553] Continuous phase: As the total amount used throughout the entire process, the amount of continuous phase used in the preparation of the emulsion is 4,000 mL, and no additional use.

[0554] Oil phase: The oil for organic solvent extraction is mixed with the continuous phase during emulsion preparation and is not pre-filled into the microsphere manufacturing tank.

[0555] MCT: Miglyol 812N

[0556]

[0557] As shown in Table 11,

[0558] In the case of Examples 4-1 to 4-5, in which the volume of organic solvent extraction oil mixed with the continuous phase during emulsion preparation is in the range of about 0.11 to 24.24 v / v%, the Span value was 1.2 or less, indicating a 'Pass' level. On the other hand, in the case of Comparative Examples 4-1 to 4-2, in which the volume is in the range of 29.91 to 34.78 v / v%, the Span value was greater than 1.2, indicating a 'Fail' level.

[0559] In other words, while the continuous phase can be used alone when preparing an emulsion, it can be confirmed that when the oil for organic solvent extraction is mixed with the continuous phase, the volume of the oil for organic solvent extraction can be used at approximately 25 v / v% or less.

[0560]

[0561] <Experimental Example 6> Evaluation according to the concentration of oil for organic solvent extraction in the final mixture

[0562] This experimental example was conducted to determine whether microspheres can be formed even when the concentration of the oil for organic solvent extraction in the final mixture of the oil for organic solvent extraction and the continuous phase in the microsphere manufacturing tank (emulsion storage tank) exceeds 50 v / v% during emulsion preparation and / or organic solvent extraction.

[0563] Specifically, as in Example 5, after stirring for 10 minutes following the completion of emulsion injection, the suspension was used as a sample and observed under an optical microscope, as shown in Fig. 10.

[0564]

[0565] As shown in Fig. 10,

[0566] The black spheres are microspheres in an emulsion and / or soft state, and the transparent spheres are oil particles. The inside of the macroscopic hazy boundary layer containing the microspheres is the aqueous phase and the outside is the oil phase, so an overall microsphere (Oil) / aqueous (Water) / oil (Oil) form is observed.

[0567] That is, it was confirmed that when the concentration of the oil for organic solvent extraction in the final mixture of the continuous phase and the oil for organic solvent extraction in the microsphere manufacturing tank (emulsion storage tank) exceeds 50 v / v%, the overall pattern is O / W / O, but the microspheres can be manufactured normally.

[0568]

[0569] [Explanation of the symbol]

[0570] 1: Dispersed phase (DP) storage tank

[0571] 2: Continuous Phase (CP) Storage Tank

[0572] 3: Oil (Oc) storage tank for organic solvent extraction

[0573] 4: Microsphere manufacturing tank

[0574] 5: Emulsion solution forming device

[0575] 6: 1st Tangential Flow Filter (TFF-1)

[0576] 7: Second Tangential Flow Filter (TFF-2)

[0577] 8: Waste

[0578] 9: Mixed continuous phase emulsion forming device

Claims

1. (a) A first emulsion comprising a dispersed phase containing a biodegradable polymer and an organic solvent, and an aqueous solution containing a surfactant and water as a continuous phase, or A dispersed phase comprising a biodegradable polymer and an organic solvent, an aqueous solution comprising a surfactant and water as a continuous phase, and an oil for organic solvent extraction (O c A step of preparing a second emulsion by mixing a mixture of ); and (b-1) Extract the organic solvent in the dispersed phase of the second emulsion of step (a) into the continuous phase to form microspheres, or (b-2) The first or second emulsion of step (a) and the oil for organic solvent extraction (O c In a mixture formed by mixing ), the organic solvent in the dispersed phase is extracted into the continuous phase to form microspheres, or (b-3) The first emulsion or second emulsion of step (a) is extracted using an oil (O) for organic solvent extraction. c A method for producing biodegradable microspheres, comprising the step of mixing with a mixture of an aqueous solution containing a surfactant and water, and extracting an organic solvent in the dispersed phase into a continuous phase to form microspheres.

2. A method of production according to claim 1, wherein the dispersed phase further comprises a drug.

3. In paragraph 1, the oil for organic solvent extraction (O c A production method comprising 10 to 10,000 parts by weight based on 100 parts by weight of the organic solvent of (a) above.

4. In claim 1, the oil for organic solvent extraction (O) in step (a) above. c A production method in which ) is used by simply mixing with an aqueous solution containing a surfactant and water, or by emulsifying.

5. In claim 1, the oil for organic solvent extraction (O) in step (b-3) above. c A production method in which ) is used by simply mixing with an aqueous solution containing a surfactant and water, or by emulsifying.

6. A method of production according to claim 1, wherein step (b-1), step (b-2) or step (b-3) involves additionally injecting a fresh continuous phase while extracting an organic solvent in the dispersed phase into the continuous phase.

7. In claim 1, in the second emulsion of step (a), the continuous phase and the oil for organic solvent extraction (O c Oil for organic solvent extraction (O) based on the total volume of the mixture c A production method in which ) is included in an amount of 0.01 to 25 (v / v)%.

8. In claim 1, in step (b-2) or step (b-3), the finally mixed continuous phase and the oil for organic solvent extraction (O c Oil for organic solvent extraction (O) based on the total volume of the mixture c A production method in which ) is included in an amount of 0.1 to 55 (v / v)%.

9. In paragraph 1, the above step (a) (a-1) A step of preparing a dispersed phase comprising a biodegradable polymer and an organic solvent, or a dispersed phase comprising a biodegradable polymer, a drug and an organic solvent, (a-2) Aqueous solution (W) containing a surfactant and water c phase) or oil for organic solvent extraction (O c A mixture (W) containing a surfactant and water. m1 Step of preparing the phase in a continuous state; (a-3) The dispersed phase of step (a-1) and the aqueous phase (W) of step (a-2) c phase or mixture (W m1 A production method comprising the step of preparing an emulsion by mixing (phase).

10. In Paragraph 1, The above oil for organic solvent extraction (O c ) is a fractionated oil, one or more C6-C 18 fatty acid triglycerides, one or more C6-C 18 fatty acid diglycerides, one or more C6-C 18 fatty acid monoglycerides, one or more C6-C 18 fatty acids, ethyl oleate, and one or more types of propylene glycol C6-C 18 A production method comprising one or more selected from the group consisting of fatty acid diesters.

11. In Paragraph 10, A method of production in which the above-mentioned fractionated oil is a fractionated oil of a vegetable oil selected from the group consisting of coconut oil, palm oil, palm kernel oil, sesame oil, soybean oil, almond oil, rapeseed oil, corn oil, sunflower oil, peanut oil, olive oil, castor oil, soybean oil, safflower oil, and cottonseed oil.

12. In Paragraph 1, The dispersion phase of step (a) above is the dispersion phase of the O / W method, the dispersion phase of the W / O / W method, or the dispersion phase of the S / O / W method, and The dispersed phase of the above O / W method is an oil phase (O) in which a biodegradable polymer is dissolved in an organic solvent. d phase), or an oil phase (O) in which biodegradable polymers and drugs are dissolved in an organic solvent d phase) and, The dispersed phase of the above W / O / W preparation method is a first aqueous phase (W) in which the drug is dissolved in an aqueous solvent. d phase) and the oil phase (O) in which biodegradable polymers are dissolved in an organic solvent d W including phase) d / O d It is an emulsion, and The dispersed phase of the above S / O / W method is an oil phase (O) in which a biodegradable polymer is dissolved in an organic solvent. d A suspension (S) containing a drug in phase) and powder form d / O d A production method that is a phase.

13. In Paragraph 1, The biodegradable polymer of step (a) above is polylactide (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) (PLGA), polydioxanone, polycaprolactone (PL), polylactide-co-glycolide-co-caprolactone (PLGC), polylactide-co-hydroxymethyl glycolide (PLGMGA), polyalkylcarbonate, polytrimethylenecarbonate (PTMC), polylactide-co-trimethylenecarbonate (PLTMC), A polymer selected from the group consisting of polyhydroxybutyric acid (PHB), polyhydroxybutyrate-co-hydroxyvalerate (PHBV), polyorthoester, polyanhydride, polyanhydride-co-imide, polypropylene fumarate, pseudo-polyaminoacid, polyalkyl cyanoacrylate, polyphosphazene, polyphosphoester, polysaccharide, and poly(butylene succinate-co-lactic acid) (PBSLA); a simple mixture of two or more of the selected polymers; A copolymer of the above-mentioned selected polymer and polyethylene glycol (PEG);A production method comprising one or more selected from the group consisting of a polymer-sugar complex in which the selected polymer or copolymer is bonded to a sugar.

14. In Paragraph 2, A method of production in which the drug of step (a) is one or more selected from the group consisting of small molecule therapeutics, synthetic compound therapeutics, peptide therapeutics, antibody therapeutics, protein therapeutics, nucleic acid therapeutics, gene therapeutics, cell therapeutics, antibody-drug conjugates (ADC) therapeutics, and radiopharmaceuticals (RPT).

15. In Paragraph 1, A method of production in which the organic solvent of step (a) is one or more selected from the group consisting of dichloromethane, dimethyl carbonate, chloroform, ethyl acetate, methyl ethyl ketone, acetone, acetonitrile, dimethyl sulfoxide, dimethylformamide, methylpyrrolidone, acetic acid, methanol, ethanol, propyl alcohol, and benzyl alcohol.

16. In Paragraph 1, A method of production in which the dispersed phase of step (a) further comprises one or more release control agents selected from the group consisting of butyric acid, valeric acid, caproic acid, enantic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecylic acid, behenic acid, arachidic acid, isocrotonic acid, oleic acid, elaidic acid, sorbic acid, linoleic acid, arachidonic acid, benzoic acid, hydroxynaphthoic acid, napadicylic acid, naphthalenesulfonic acid, and pamosan.

17. In Paragraph 1, A method of production in which the surfactant of step (a) is one or more selected from the group consisting of polyvinyl alcohol, methylcellulose, polyvinylpyrrolidone, carboxymethylcellulose, lecithin, gelatin, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene castor oil derivative.

18. In Paragraph 1, A method of production in which the aqueous solution of step (a) further comprises one or more selected from the group consisting of methanol, ethanol, propyl alcohol, and ethyl acetate.

19. In Paragraph 1, The aqueous solution of step (a) above is, A method of production further comprising one or more early release inhibitors selected from the group consisting of phosphate salts, hydroxide salts, phosphide salts, phosphite salts, carbonate salts, bicarbonate salts, chromate salts, dichromate salts, oxides, oxalates, silicates, sulfate salts, sulfide salts, sulfite salts, tartrate salts, tetraborate salts, thiosulfate salts, arsenates, arsenites, citrates, ferricyanides, and nitride salts of alkali metals, alkaline earth metals, or ammoniums.

20. In Paragraph 6, The above fresh continuous phase is, A method of production further comprising one or more early release inhibitors selected from the group consisting of phosphate salts, hydroxide salts, phosphide salts, phosphite salts, carbonate salts, bicarbonate salts, chromate salts, dichromate salts, oxides, oxalates, silicates, sulfate salts, sulfide salts, sulfite salts, tartrate salts, tetraborate salts, thiosulfate salts, arsenates, arsenites, citrates, ferricyanides, and nitride salts of alkali metals, alkaline earth metals, or ammoniums.

21. In Paragraph 1, A production method in which the formation of the emulsion in step (a) above is achieved using a membrane emulsification device, an inline mixer, a static mixer, or a microfluidic system.

22. In Paragraph 1, A production method wherein step (b-1), (b-2) or (b-3) further comprises a heat treatment for evaporating an organic solvent.

23. A method for manufacturing an injectable composition comprising dried microspheres, comprising the step of drying microspheres manufactured by a production method according to any one of claims 1 to 22, and then filling the dried microspheres into a container.

24. In Paragraph 23, A step of washing microspheres produced by a production method according to any one of claims 1 to 22 to remove surfactants remaining on the surface of the microspheres; A step of drying the recovered microspheres after recovering the microspheres; and A manufacturing method comprising the step of filling a container with dried microspheres.

25. In Paragraph 1, After the above steps (b-1), (b-2), or (b-3), the method comprises the step of performing an aggregation reduction treatment on the obtained microspheres. The step of performing the above-mentioned aggregation reduction treatment is: Oil for organic solvent extraction (O c Treat with a microsphere aggregation reduction treatment solution (treatment solution A) containing ) and a surfactant, or Oil for organic solvent extraction (O c After treatment with a microparticle aggregation reduction treatment solution (treatment solution A) containing ) and a surfactant, an oil for organic solvent extraction (O c Treat with a microsphere aggregation reduction treatment solution (treatment solution B) containing ) and a water-miscible solvent, or Oil for organic solvent extraction (O c A production method performed by treating with a microsphere aggregation reduction treatment solution (treatment solution C) comprising a surfactant and a water-miscible solvent.

26. In Paragraph 25, A method of production in which the above surfactant is one or more selected from a hydrophilic-lipophile balance (HLB) value in the range of 3 to 8.

27. In Paragraph 25, A method of production in which the above-mentioned water-miscible solvent is one or more selected from the group consisting of methanol, ethanol, propanol, acetone, isopropyl alcohol, cetyl alcohol, and benzyl alcohol.

28. A step of suspending microspheres produced by the production method according to paragraph 25 in a non-aqueous vehicle; and A method for preparing an injectable composition comprising microparticles suspended in a non-aqueous vehicle, comprising the step of filling a container with a non-aqueous vehicle in which the microparticles are suspended.

29. A step of transferring microspheres produced by the production method according to paragraph 25 to a storage tank for the main composition; A step of preparing a non-aqueous vehicle in which microspheres are suspended by injecting the non-aqueous vehicle into the storage tank of the above-mentioned main composition; and A method for preparing an injectable composition comprising microparticles suspended in a non-aqueous vehicle, comprising the step of filling a container with a non-aqueous vehicle in which the microparticles are suspended.

Images