Dry formulations for tissue repair

Abstract

The present invention relates to a dry formulation for tissue repair, and specifically, to a dry formulation for tissue repair comprising a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer and an additive, wherein the formulation exhibits an excellent tissue repair effect upon injection into a human body after reconstitution in an aqueous medium.

Description

Technical Field

[0001] This invention relates to a dry preparation for tissue repair, and more specifically, to a dry preparation for tissue repair comprising a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer, as well as additives, which exhibits excellent tissue repair effects after being reconstituted in an aqueous medium and introduced into the body. Background Technology

[0002] In recent years, many people have become interested in well-aging, which refers to aging gracefully from a young age. It's no exaggeration to say that the current beauty market is primarily focused on anti-aging—that is, aging slowly, beautifully, and healthily. One of the most common signs of aging is loss of volume. Specifically, because a lack of facial volume leads to an aged and haggard appearance, there is great interest in fillers that can increase volume. As a result, the filler market is growing rapidly every year, and the global market size has now exceeded 2 trillion won.

[0003] Currently, various substances are used as filler materials, with hyaluronic acid fillers accounting for over 90% of the global filler market. However, its problem lies in its half-life in the body, which is only 1 to 3 days, resulting in low durability and rapid reabsorption. Therefore, products on the market extend the reabsorption time by linking hyaluronic acid with cross-linking materials. However, in the case of such cross-linked products, the cross-linking material BDDE (1,4-butanediol diglycidyl ether) is a toxic carcinogen, leading to the following problems: increased process costs depending on its removal process, and losses due to product handling caused by microbial contamination and residue detection.

[0004] Therefore, many tissue repair products using polymers that decompose in vivo have been developed, and formulations using conventional biocompatible polymers have been developed and used by processing water-insoluble polymers into micron-sized particles and then dispersing them with viscous excipients or thickeners. For example, formulations in which polylactide (PLA) particles with a diameter of 20 to 50 micrometers are dispersed in an aqueous solution of carboxymethyl cellulose (CMC), or formulations in which poly(caprolactone) (PCL) particles with a diameter of 20 to 50 micrometers are dispersed in an aqueous solution of CMC and glycerol have been used. However, such formulations have problems such as inconvenience caused by microparticles clogging the needle during injection, and the inability to obtain uniform tissue repair effects due to uneven particle dispersion.

[0005] Therefore, there is an urgent need to develop a tissue repair product and its preparation method, which can ensure the functionality, performance and safety of biomaterials used for tissue repair without generating toxicity risks caused by chemical cross-linking processes. Summary of the Invention

[0006] Technical issues

[0007] The purpose of this invention is to provide a tissue repair product, which is a dry preparation that is easy to transport, store and handle. After being reconstituted in an aqueous medium and introduced into the body, it exhibits excellent tissue repair effects without any toxicity risk. This ensures the functionality, performance and safety of tissue repair biomaterials without any toxicity risk.

[0008] Technical solution

[0009] In one aspect, the present invention provides a dry preparation for tissue repair, the dry preparation comprising: a biocompatible copolymer, said biocompatible copolymer being a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and an additive; wherein when said dry preparation is reconstituted in an aqueous medium, the reconstituted composition exhibits thixotropy with increasing viscosity over time.

[0010] In another aspect, the present invention provides a method for preparing a dry preparation for tissue repair, the method comprising the steps of: (1) dissolving or dispersing a biocompatible copolymer and an additive in a mixture of an organic solvent and an aqueous medium, wherein the biocompatible copolymer is a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and (2) drying the product of step (1); wherein when the product of step (2) is reconstituted in an aqueous medium, the reconstituted composition exhibits thixotropy with increasing viscosity over time.

[0011] In another aspect, the present invention provides an injectable composition for tissue repair comprising a dry preparation for tissue repair; and a pharmaceutically acceptable carrier for injection.

[0012] In another aspect, the present invention provides a method for preparing an injectable composition for tissue repair, the method comprising: mixing a dry preparation for tissue repair with a pharmaceutically acceptable carrier for injection at room temperature.

[0013] Beneficial effects

[0014] The dry formulation for tissue repair of the present invention is easy to transport, store and handle. When reconstituted in an aqueous medium, the reconstituted composition exhibits thixotropy with increasing viscosity over time, thus showing excellent tissue repair effects after in vivo, and without any toxic risks, ensuring the functionality, performance and safety of biomaterials suitable for tissue repair. Attached Figure Description

[0015] Figure 1 The results of shear stress measurements (X-axis: shear rate (1 / s), Y-axis: shear stress (Pa)) are shown for each dry formulation prepared in Examples 1 to 4 and Comparative Example 2 of the present invention, measured immediately after reconstruction in an aqueous medium and at a certain time after reconstruction. However, in the case of Comparative Example 3, the results are the results of shear stress measurements performed immediately after the preparation of the prepared dispersion and 1 hour after preparation.

[0016] Figure 2 The results of the animal experiment conducted in Experimental Example 3 of the present invention are shown.

[0017] Figure 3 The scoring criteria used in Experiment Example 3 of the present invention are shown. Detailed Implementation

[0018] The present invention will be explained in detail below.

[0019] The dry preparation for tissue repair of the present invention comprises a biocompatible copolymer, wherein the biocompatible copolymer is a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and an additive.

[0020] In this invention, "dry preparation" encompasses all preparations in a dried state, without particular limitation on their form or the drying method used to prepare them. For example, they can be dried into a form such as powder by freeze drying, vacuum drying, or other drying methods (e.g., rotary drying, spray drying), but are not limited thereto.

[0021] In one embodiment, the dry preparation for tissue repair of the present invention may be in the form of powder, sponge, packing material (stick) or beads, but is not limited thereto.

[0022] In one embodiment, the hydrophilic biocompatible polymer may be selected from the group consisting of polyethylene glycol or its derivatives (e.g., alkoxy polyethylene glycol or hydroxy polyethylene glycol), polyvinylpyrrolidone, polyvinyl alcohol, polyacrylamide, and combinations thereof, and more specifically, may be selected from the group consisting of polyethylene glycol (PEG), methoxy polyethylene glycol (mPEG), and combinations thereof.

[0023] In one embodiment, the hydrophobic biocompatible polymer may be a polymer of α-hydroxy acid-derived monomers, and more specifically, it may be selected from the group consisting of polylactide, polyglycolic acid, poly(lactide-glycolic acid), polymandelic acid, polycaprolactone, polydioxane-2-one, polyamino acid, polyorthoester, polyanhydride, polycarbonate, polytrimethylene carbonate, polyβ-hydroxybutyrate, polyhydroxyvalerate, and combinations thereof, and more specifically, it may be selected from the group consisting of polylactide, polyglycolic acid, poly(lactide-glycolic acid), and combinations thereof.

[0024] Specifically, the GPC number-average molecular weight (in g / mol) of the hydrophilic biocompatible polymer (Mn1) can be above 1000, above 2000, above 3000, above 4000, above 5000, above 6000, above 7000, above 8000, or above 9000, and it can also be below 30000, below 29000, below 28000, below 27000, below 26000, below 25000, below 24000, below 23000, below 22000, or below 21000, but is not limited to these.

[0025] Specifically, the GPC number-average molecular weight (unit: g / mol) of the hydrophobic biocompatible polymer (Mn2) can be above 500, above 1000, above 2000, above 3000, above 4000, or above 5000, and it can also be below 20000, below 19000, below 18000, below 17000, below 16000, below 15000, below 14000, below 13000, below 12000, or below 11000, but is not limited to these.

[0026] Specifically, the total average molecular weight of the biocompatible copolymer (GPC) can be above 1500, above 2000, above 5000, above 7000, above 9000, above 10000, above 12000, or above 14000, and it can also be below 50000, below 48000, below 45000, below 42000, below 40000, below 38000, below 35000, or below 32000, but is not limited to these.

[0027] In one embodiment, the ratio (Mn1 / Mn2) of the number-average molecular weight (Mn1) of the hydrophilic biocompatible polymer to the number-average molecular weight (Mn2) of the hydrophobic biocompatible polymer in the biocompatible copolymer can be 2.5 or less.

[0028] Specifically, the number-average molecular weight ratio (Mn1 / Mn2) of the hydrophilic biocompatible polymer to the hydrophobic biocompatible polymer can be less than 2.5, less than 2.4, less than 2.3, or less than 2.2, and it can also be greater than 0.6, greater than 0.7, greater than 0.8, or greater than 0.9, but is not limited to these.

[0029] The number-average molecular weights of hydrophilic and hydrophobic biocompatible polymers can be measured, for example, by gel permeation chromatography (GPC).

[0030] Gel permeation chromatography (GPC) is a method in which the physical elution mechanism is based on the hydrodynamic volume of the analytes, eluting the larger components first and then the smaller components. Therefore, large molecules cannot enter the pores of the porous gel and pass through quickly, while small molecules can enter the pores of the gel and remain there and pass through slowly. The relative molecular weight is analyzed according to the order of the speed at which the molecules pass through the chromatographic column.

[0031] In one embodiment, the biocompatible copolymer can be prepared by a method comprising the steps of: polymerizing monomers for the hydrophobic biocompatible polymer in the presence of the hydrophilic biocompatible polymer to prepare a copolymer of the hydrophilic and hydrophobic biocompatible polymers; and drying the prepared copolymer, but not limited thereto.

[0032] In the presence of a hydrophilic biocompatible polymer, the polymerization of monomers for a hydrophobic biocompatible polymer can be carried out according to known methods and conditions.

[0033] Specifically, the drying of biocompatible copolymers can be carried out by freeze-drying or other drying methods (e.g., rotary drying), more specifically, but not limited to freeze-drying. As mentioned above, the freeze-drying of biocompatible copolymers can be carried out in the presence of freeze-drying aids, but is not limited to this.

[0034] In one embodiment, the additive may be selected from the group consisting of buffers, freeze-drying aids, isotonic agents, or combinations thereof.

[0035] In one embodiment, the buffer may be selected from the group consisting of sodium dihydrogen phosphate (NaH2PO4), disodium hydrogen phosphate (Na2HPO4), potassium dihydrogen phosphate (KH2PO4), dipotassium hydrogen phosphate (K2HPO4), sodium citrate, sodium acetate, sodium bicarbonate, sodium carbonate, or combinations thereof.

[0036] Buffers contain their hydrates. That is, for example, "disodium hydrogen phosphate" contains the hydrates of disodium hydrogen phosphate (e.g., dihydrate, heptahydrate, etc.).

[0037] In one implementation, the buffer may comprise a combination of disodium hydrogen phosphate and sodium dihydrogen phosphate.

[0038] In one embodiment, where the buffer comprises a combination of disodium hydrogen phosphate (or dipotassium hydrogen phosphate) and sodium dihydrogen phosphate (or potassium dihydrogen phosphate), the molar ratio of disodium hydrogen phosphate (or dipotassium hydrogen phosphate) to sodium dihydrogen phosphate (or potassium dihydrogen phosphate) may be 6–8:4–2, more specifically 6.5–7.5:3.5–2.5, and even more specifically 6.8–7.2:3.2–2.8, but is not limited thereto.

[0039] In one embodiment, the phosphate buffer may be used in a suitable amount, such as 5 to 10 mg per 1g of biocompatible copolymer, but is not limited thereto.

[0040] In one embodiment, the freeze-drying aid (also known as a freeze-drying agent) may be selected from one or more of the group consisting of lactose, maltose, sucrose, trehalose, mannitol, sorbitol, maltitol, xylitol and lactitol.

[0041] In one embodiment, the amount of the freeze-drying aid may be from 0.1% to 20% by weight, more specifically from 0.5% to 10% by weight, but is not limited thereto.

[0042] In one embodiment, the isotonic agent may be selected from, but is not limited to, sodium chloride, potassium chloride, calcium chloride, glucose, boric acid, or combinations thereof.

[0043] In one embodiment, the amount of isotonic agent used can be from 0.1% to 20% by weight, more specifically from 0.5% to 10% by weight, but is not limited thereto.

[0044] In one embodiment, the dry preparation for tissue repair of the present invention may further comprise a local anesthetic.

[0045] Specifically, local anesthetics can be selected from ammoocaine, amolanone, amylocaine, benoxinate, benzocaine, betoxycaine, biphenamine, bupivacaine, butacaine, butamben, butanilicaine, butethamine, butoxycaine, carticaine, chloroprocaine, cocaethylene, and cocaine. ine), cyclomethycaine, dibucaine, dimethisoquin, dimethocaine, diperodon, dicyclonine, ecgonidine, ecgonine, ethyl chloride, eticaine, beta-eucaine, euprocin, fenalcomine, formocaine, hexylcaine, hydroxytetracaine, isobutyl p-aminobenzoate, leucinocainemesylate, levoxadrol, lidocaine, mepivacaine, meprylcaine, metabutoxycaine, methylchloride, myrtecaine, naepaine, octacaine, orthocaine, oxethazaine, parethoxycaine, phenacaine, phenol The group consisting of one or more of the following: piperocaine, piridocaine, polidocanol, pramoxine, prilocaine, procaine, propanocaine, proparacaine, propipocaine, propoxycaine, pseudococaine, pyrrocaine, ropivacaine, salicyl alcohol, tetracaine, tolycaine, trimecaine, zolamine, and their salts.

[0046] In one embodiment, the dry formulation for tissue repair of the present invention may further comprise one or more components selected from the group consisting of polynucleotide fractions, polynucleotide fragments, biocompatible polymers, or combinations thereof.

[0047] Specifically, a polynucleotide fraction or fragment refers to a polymer composed of nucleotide units. Preferably, it may contain nucleotide units, including adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U). These units may also be modified, and the modified units may include 4-acetylcytidine, 5-(carboxyhydroxymethyl)uridine, 2-O-methylcytidine, 5-carboxymethylaminomethyl-2-thiouridine, 5-carboxymethylamino-methyluridine, dihydrouridine, 2-O-methylpseuuridine, 2-O-methylguanosine, inosine, N6-isopentyladenosine, 1-methyladenosine, 1-methylpseuuridine, 1-methylguanosine, 1-methylinosine, 2,2-dimethylguanosine, 2-methyladenosine, 2-methylguanosine, 3-methylcytidine, 5-methylcytidine, N6-methyladenosine, 7-methylguanosine, 5-methylaminomethyluridine. 5-Methoxyaminomethyl-2-thiouridine, 5-Methoxyuridine, 5-Methoxycarbonylmethyl-2-thiouridine, 5-Methoxycarbonylmethyluridine, 2-Methylthio-N6-isopentyladenosine, uridine-5-oxyacetic acid-methyl ester, uridine-5-oxyacetic acid, wybutoxosine, wybutosine, pseudouridine, queuosine, 2-thiocytidine, 5-methyl-2-thiouridine, 2-thiouridine, 4-thiouridine, 5-methyluridine, 2-O-methyl-5-methyluridine, 2-O-methyluridine, etc., but not limited to these.

[0048] Furthermore, polynucleotides are naturally occurring nucleic acids, such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), and can be single-stranded or double-stranded. They can also include nucleic acid analogs, which contain non-naturally occurring bases, nucleotides linked to nucleotides other than naturally occurring phosphodiester bonds, or nucleotides containing bases linked by links other than phosphodiester bonds. Nucleic acid analogs include, but are not limited to, thiophosphates, dithiophosphates, triphosphates, aminophosphates, boranophosphates, methylphosphonates, chiral methylphosphonates, 2-O-methylribonucleotides, or peptide nucleic acids (PNAs). Polynucleotides can also be polynucleotides containing synthetic or modified nucleotides. Many different types of modifications to oligonucleotides are known in the art.

[0049] Specifically, the biocompatible polymer can be hyaluronic acid. Hyaluronic acid refers to all hyaluronic acid itself, its salts, and derivatives, and may include aqueous solutions of all hyaluronic acid, aqueous solutions of hyaluronic acid salts, and mixtures thereof. Hyaluronic acid salts may be selected from one or more of the group consisting of sodium hyaluronate, potassium hyaluronate, calcium hyaluronate, magnesium hyaluronate, zinc hyaluronate, cobalt hyaluronate, and tetrabutylammonium hyaluronate.

[0050] The dry formulation for tissue repair of the present invention can be prepared by dissolving or dispersing the above-mentioned biocompatible copolymer in a suitable solvent and then drying it, but is not limited thereto.

[0051] Specifically, another aspect of the present invention provides a method for preparing a dry formulation for tissue repair, the method comprising the steps of: (1) dissolving or dispersing a biocompatible copolymer and an additive in a mixture of an organic solvent and an aqueous medium, wherein the biocompatible copolymer is a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and (2) drying the product of step (1); wherein when the product of step (2) is reconstituted in an aqueous medium, the reconstituted composition exhibits thixotropy with increasing viscosity over time.

[0052] According to one embodiment, in a method for preparing a dry preparation for tissue repair, a biocompatible copolymer (which is a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer) can be dissolved or dispersed in an aqueous medium containing an organic solvent and an additive (e.g., a buffer), and then the resulting liquid can be freeze-dried.

[0053] In one embodiment, the organic solvent may be selected from one or more of the group consisting of ketone solvents, alcohol solvents, sulfone solvents, nitrile solvents, ether solvents, amide solvents, alkane solvents, and combinations thereof, and more specifically, it may be a ketone solvent or a mixture of solvents containing it, but is not limited thereto.

[0054] In one embodiment, the ketone solvent may consist of or comprise one or more substituted or unsubstituted straight-chain or cyclic aliphatic ketones, more specifically, straight-chain or cyclic aliphatic ketones with a total carbon number of 3 to 10, even more specifically, straight-chain or cyclic aliphatic ketones with a total carbon number of 3 to 7, and even more specifically, straight-chain aliphatic ketones with a total carbon number of 3 to 5. For example, the ketone solvent may be acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl n-propyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-pentanone (or 2-heptanone), or combinations thereof, but is not limited thereto.

[0055] In one embodiment, the alcohol-based solvent may consist of or contain one or more fatty alcohols having a total carbon number of 1 to 6, more specifically, fatty alcohols having a total carbon number of 1 to 4. For example, the alcohol-based solvent may be ethanol, methanol, tert-butanol, isopropanol, or combinations thereof, but is not limited thereto.

[0056] In one embodiment, the sulfone-based solvent may consist of or contain one or more sulfoxides having a total carbon number of 2 to 6, more specifically, sulfoxides having a total carbon number of 2 to 4. For example, the sulfone-based solvent may be dimethyl sulfoxide, diethyl sulfoxide, or combinations thereof, but is not limited thereto.

[0057] In one embodiment, the nitrile solvent may consist of or contain one or more nitriles having a total carbon number of 2 to 8, more specifically, nitriles having a total carbon number of 2 to 6. For example, the nitrile solvent may be acetonitrile, but is not limited thereto.

[0058] In one embodiment, the ether solvent may be one or more straight-chain aliphatic ethers or cyclic aliphatic ethers having a total carbon number of 2 to 8, or may contain one or more straight-chain aliphatic ethers or cyclic aliphatic ethers having a total carbon number of 2 to 8, more specifically, straight-chain aliphatic ethers or cyclic aliphatic ethers having a total carbon number of 2 to 6. For example, the ether solvent may be 1,4-dioxane, but is not limited thereto.

[0059] In one embodiment, the amide solvent may consist of or contain one or more amides having a total carbon number of 2 to 8, more specifically amides having a total carbon number of 2 to 6. For example, the amide solvent may be dimethylacetamide, but is not limited thereto.

[0060] In one embodiment, the alkane-based solvent may consist of or contain one or more straight-chain alkanes or cycloalkanes having a total carbon number of 4 to 10, more specifically, straight-chain alkanes or cycloalkanes having a total carbon number of 4 to 8. For example, the alkane-based solvent may be cyclohexane, but is not limited thereto.

[0061] There is no particular limitation on the amount of organic solvent used; any amount sufficient to dissolve all biocompatible copolymers is adequate. In one embodiment, the amount of organic solvent used per 1g of biocompatible copolymer can be from 1ml to 10ml, more specifically from 1ml to 5ml, but is not limited thereto.

[0062] In one embodiment, the aqueous medium may be distilled water, purified water, deionized water, ultrapure water, saline, or a combination thereof, but is not limited thereto.

[0063] In one embodiment, the aqueous medium containing additives (e.g., buffers) may be a phosphate buffer solution, but is not limited thereto.

[0064] In one embodiment, the amount of aqueous medium used can be from 2 ml to 40 ml per 1 g of biocompatible copolymer, more specifically from 4 ml to 20 ml, but is not limited thereto.

[0065] In one embodiment, the concentration of the biocompatible copolymer in the biocompatible polymer copolymer dispersion may be from 0.1% by weight to 50% by weight, more specifically from 1% by weight to 30% by weight, but is not limited thereto.

[0066] According to one embodiment, prior to freeze-drying, a freeze-drying aid can be added to a copolymer solution or dispersion prepared using an organic solvent and an aqueous medium.

[0067] In one embodiment, freeze drying can be carried out at a temperature of -45°C to -15°C, and more specifically, at a temperature of -40°C to -20°C.

[0068] The dry formulation for tissue repair of the present invention is readily soluble in an aqueous medium at room temperature to form polymer particles. After being introduced into the body, the particles self-assemble under the influence of the in vivo environment through the hydrophobic aggregation of hydrophobic polymers to form large structures that are not phagocytosed by macrophages and induce collagen production, thereby exhibiting excellent tissue repair effects.

[0069] Furthermore, when the dry formulation of the present invention for tissue repair is reconstituted in an aqueous medium, the reconstituted composition exhibits thixotropy with increasing shear stress (i.e. viscosity) over time, thus providing excellent tissue repair effects when introduced into the human body.

[0070] In one embodiment, when the dry formulation of the present invention for tissue repair is reconstituted in an aqueous medium, the reconstituted composition can exhibit shear stress measured 1 hour after reconstitution that is more than 1.5 times that measured immediately after reconstitution under the same conditions.

[0071] More specifically, the dry formulation of the present invention for tissue repair, when reconstituted to a concentration of 12.5% ​​by weight in an aqueous medium (e.g., 25°C) (hereinafter referred to as the 12.5% ​​by weight reconstituted composition), can exhibit shear stress (hereinafter referred to as "shear stress (1 hour)") measured at a shear rate of 10 / second 1 hour after reconstitution, which is more than 1.5 times that of the shear stress (hereinafter referred to as "shear stress (initial)") measured immediately after reconstitution under the same conditions.

[0072] More specifically, the shear stress (1 hour) of 12.5% ​​by weight of the reconstructed composition can be, but is not limited to, more than 1.5 times, 1.6 times, 1.7 times, 1.8 times, 1.9 times, 2 times, 2.1 times, 2.2 times, 2.3 times, 2.4 times, 2.5 times, 2.6 times, 2.7 times, 2.8 times, 2.9 times, or 3 times the initial shear stress. Furthermore, the shear stress (1 hour) of 12.5% ​​by weight of the reconstructed composition can be less than 6 times, 5.5 times, 5 times, 4.5 times, or 4 times the initial shear stress.

[0073] Furthermore, in one embodiment, when the dry formulation of the present invention for tissue repair is reconstituted in an aqueous medium, the reconstituted composition can exhibit shear stress measured 6 hours after reconstitution that is more than twice the shear stress measured immediately after reconstitution under the same conditions.

[0074] More specifically, 12.5% ​​by weight of the reconstructing composition of the dry preparation for tissue repair of the present invention can exhibit a shear stress (hereinafter referred to as "shear stress (6 hours)") measured at a shear rate of 10 / second 6 hours after reconstruction that is more than twice the shear stress (initial).

[0075] More specifically, the shear stress (6 hours) of 12.5% ​​by weight of the reconstructed composition can be more than 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4 times the initial shear stress, but is not limited thereto. Furthermore, the shear stress (6 hours) of 12.5% ​​by weight of the reconstructed composition can be less than 8, 7.5, 7, 6.5, 6, 5.5, or 5 times the initial shear stress, but is not limited thereto.

[0076] In this invention, tissue repair refers to the function of restoring skin tissue to its original state when skin tissue suffers necrosis or defects due to trauma, inflammation, aging, etc.

[0077] Therefore, another aspect of the present invention provides an injectable composition for tissue repair comprising the dry formulation of the present invention for tissue repair; and a pharmaceutically acceptable carrier for injection.

[0078] As a pharmaceutically acceptable carrier for injection included in the injectable composition for tissue repair of the present invention, conventional carriers can be used without limitation, such as those selected from the group consisting of distilled water for injection, physiological saline, 5% glucose, buffer solutions (e.g., phosphate buffered solution (PBS)), hyaluronic acid solution, and combinations thereof, but not limited thereto.

[0079] In addition to the above-mentioned components, the injectable composition for tissue repair of the present invention may also contain one or more conventional additives that can be used in injectable formulations.

[0080] Another aspect of the invention provides a method for preparing an injectable composition for tissue repair, the method comprising: mixing the dry formulation of the invention for tissue repair with a pharmaceutically acceptable carrier for injection (preferably at room temperature). Here, "room temperature" means 1°C to 30°C, 20°C to 30°C, 22°C to 28°C, and more specifically 24°C to 26°C (e.g., 25°C).

[0081] Existing polymer products for tissue repair must be heated (e.g., the temperature must be raised to between the polymer's melting point and the boiling point of water) to be manufactured in aqueous solution form. However, the dry formulations for tissue repair prepared by the method of the present invention readily dissolve in aqueous media even at room temperature, thus their injectable compositions in aqueous solution form can be readily prepared and used at room temperature.

[0082] The present invention will now be explained in more detail through the following embodiments and comparative examples. However, the scope of the present invention is not limited in any way.

[0083] [Example]

[0084] Example 1

[0085] To obtain a biocompatible copolymer with a target number-average molecular weight (Mn) of 15000 g / mol, D,L-lactide monomers were polymerized in the presence of a catalyst in the presence of methoxy polyethylene glycol (mPEG), which is a hydrophilic biocompatible polymer with a number-average molecular weight (Mn1) of 9850 g / mol (measured by GPC). The resulting copolymer was then dried. As measured by GPC, the prepared mPEG-poly(D,L-lactide) copolymer had a number-average molecular weight (Mn) of 15500 g / mol. The molecular weight of the hydrophobic polymer was calculated by subtracting the molecular weight of the hydrophilic polymer from the measured molecular weight of the copolymer. The ratio (Mn1 / Mn2) of the number-average molecular weight of mPEG (the hydrophilic polymer in the copolymer) to that of poly(D,L-lactide) (the hydrophobic polymer in the copolymer) was 1.74.

[0086] A dispersion of the copolymer was prepared using a linear fatty ketone solvent with a total carbon number of 4 and a phosphate buffer. 10% by weight of D-mannitol was added to the prepared dispersion as a freeze-drying aid to prepare a mixture for freeze-drying, which was then freeze-dried to prepare a powdered dry preparation for tissue repair.

[0087] Example 2

[0088] Except that the target number-average molecular weight (Mn) of the biocompatible copolymer was set to 17000 g / mol, the powder formulation was prepared in the same manner as in Example 1. As a result of GPC measurements, the number-average molecular weight (Mn) of the prepared mPEG-poly(D,L-lactide) copolymer was 17100 g / mol. The molecular weight of the hydrophobic polymer was calculated by subtracting the molecular weight of the hydrophilic polymer from the measured molecular weight of the copolymer. The ratio (Mn1 / Mn2) of the number-average molecular weight of mPEG (the hydrophilic polymer in the copolymer) to the number-average molecular weight (Mn2) of poly(D,L-lactide) (the hydrophobic polymer in the copolymer) was 1.36.

[0089] A dry preparation for tissue repair in powder form was prepared by using the prepared copolymer in the same manner as in Example 1.

[0090] Example 3

[0091] Except that the target number-average molecular weight (Mn) of the biocompatible copolymer was set to 20,000 g / mol, the powder formulation was prepared in the same manner as in Example 1. As a result of GPC measurements, the number-average molecular weight (Mn) of the prepared mPEG-poly(D,L-lactide) copolymer was 20,200 g / mol. The molecular weight of the hydrophobic polymer was calculated by subtracting the molecular weight of the hydrophilic polymer from the measured molecular weight of the copolymer. The ratio (Mn1 / Mn2) of the number-average molecular weight (Mn1) of mPEG (the hydrophilic polymer in the copolymer) to the number-average molecular weight (Mn2) of poly(D,L-lactide) (the hydrophobic polymer in the copolymer) was 0.95.

[0092] A dry preparation for tissue repair in powder form was prepared by using the prepared copolymer in the same manner as in Example 1.

[0093] Example 4

[0094] Except for using a straight-chain fatty ketone solvent with a total carbon number of 3, a dry preparation for tissue repair in powder form was prepared in the same manner as in Example 1 by using the biocompatible copolymer prepared in Example 1.

[0095] Comparative Example 1

[0096] Miracle L, a commercially available liquid product known to generate collagen, was used as Comparative Example 1.

[0097] Comparative Example 2

[0098] Except that only phosphate buffer was used instead of organic solvents when preparing the polymer dispersion solution, a dry preparation for tissue repair in powder form was prepared in the same manner as in Example 1 by using the biocompatible copolymer prepared in Example 1.

[0099] Comparative Example 3

[0100] Except that only phosphate buffer was used without organic solvents, a dispersion was prepared in the same manner as in Example 1 using the biocompatible copolymer prepared in Example 1. 10% by weight of D-mannitol was added to the prepared dispersion as a freeze-drying aid. The concentration of the dispersion was the same as that reconstructed in Experimental Example 2.

[0101] Experimental Example 1: Analysis of Polymer Molecular Weight

[0102] The number-average molecular weight (Mn) of the copolymers prepared in Examples 1 to 3 was measured by gel permeation chromatography (GPC) under the conditions shown in the table below.

[0103] instrument Agilent Infinity 1260GPC / SEC System chromatographic column One Mixed-C guard column and two Mixed-C analytical columns Elution solution Chloroform (HPLC grade) detector Refractive index (RI) detector Flow rate 1.0 mL / min temperature 35℃ concentration 0.1–0.2% by weight / volume Injection volume 100μL Standard materials Nine types of PS (195300 / 69650 / 30230 / 19500 / 12980 / 6320 / 3090 / 1290 / 945g / mol)

[0104] Experimental Example 2: Measurement of Shear Stress

[0105] By adding water for injection, each dry formulation for tissue repair from Examples 1 to 4 and Comparative Example 2 was reconstituted into an aqueous composition with a concentration of 12.5% ​​by weight. The shear stress of the reconstituted compositions was measured immediately after reconstitution, and at 1 hour and 6 hours after reconstitution, while the shear rate was increased from 0.1 / s to 10 / s. In the case of Comparative Example 3, the shear stress was measured immediately after preparation and at 1 hour after preparation. The results are shown in Table 1 below. Figure 2 As shown.

[0106] Rheometer (MCR102e, Anton Paar) parameter settings

[0107] Temperature: 25℃

[0108] Shear rate: 0.1 / sec to 10 / sec (slope linear)

[0109] Injection volume: 500 μl

[0110] Plate diameter: 25mm

[0111] Gap between the plate and the glass: 0.8mm

[0112] Results: Shear rate and shear stress

[0113] [Table 1] Shear stress measured at a shear rate of 10 / second

[0114]

[0115] *: Indicates the "Preparation of Dispersion Solution" in Comparative Example 3.

[0116] Experimental Example 3: Verifying the efficacy of the preparation as a tissue repair agent through animal experiments.

[0117] The efficacy of the powdered dry formulation according to the present invention for tissue repair was verified through animal studies. Animal studies were conducted using 5-week-old SD rats (purchased from Orient Bio Co., Ltd.).

[0118] In the animal experiments, each 5-week-old SD rat was bilaterally administered physiological saline and experimental materials. During the experiment, the rearing environment was set at a temperature of 24±2℃, a relative humidity of 50±10%, and a light exposure time of 12 hours, with free access to food.

[0119] Using physiological saline as a control, the reconstituted compositions of each dry formulation in powder form prepared in Examples 1 to 4 and Comparative Example 2 were dissolved in water for injection (12.5% ​​by weight) as test materials, and continuously injected at a volume of 100 μL into the liquid formulations of Comparative Example 1 (Miracle L, a commercial liquid product) and Comparative Example 3 (dispersion solution). After 4 weeks, the test animals were sacrificed, and the injection sites were marked with Masson's Trichrome (MT). Figure 3 Skin tissue (in the area indicated by the arrow in the upper part) was stained to observe collagen formation and assess the ability to biosynthesize new collagen. Results are as follows: Figure 3 As shown ( Figure 3 (the lower part).

[0120] In addition, the sites where new collagen is generated were scored according to the following criteria, and the results are shown in Table 2 below.

[0121] Classification Evaluation criteria (refer to) Figure 3 ) Score 4 The product has clear boundaries and a sense of volume. Score 3 The product has clear boundaries and no sense of volume. Score 2 The product boundary was not clear, and no capillaries were visible beneath the product. Score 1 The product boundary was not clear, and capillaries were visible beneath the product. Score 0 No product was observed compared to the control.

[0122] [Table 2]

[0123]

[0124] In addition, a relative evaluation was performed by measuring the thickness of the areas where new collagen was generated, compared with the thickness of the control. The results are shown in Table 3 below.

[0125] [Table 3]

[0126]

[0127] from Figure 3 The results in Tables 2 and 3 confirm that, compared with the comparative example, the reconstructed compositions of the dry formulations of the examples exhibit superior and better collagen formation, particularly the formation of a large number of collagen fibers that are significantly thicker than those of Comparative Example 1 (Miracle L).

[0128] In other words, it can be confirmed that, compared with the commercial product (Miracle L) of Comparative Example 1, the dry formulation according to the present invention has the advantages of being easy to transport, store and handle, is easily soluble in aqueous media at room temperature, and when introduced into the body, it more effectively induces collagen formation, thereby exhibiting a superior tissue repair effect.

Claims

1. A dry formulation for tissue repair, the dry formulation for tissue repair comprising: a biocompatible copolymer that is a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and an additive; wherein when the dry formulation is reconstituted in an aqueous medium, the composition thus reconstituted exhibits thixotropy with increasing viscosity over time.

2. The dry formulation for tissue repair of claim 1, wherein the hydrophilic biocompatible polymer is selected from the group consisting of polyethylene glycol or derivatives thereof, polyvinylpyrrolidone, polyvinyl alcohol, polyacrylamide, and combinations thereof.

3. The dry formulation for tissue repair of claim 1, wherein the hydrophobic biocompatible polymer is selected from the group consisting of polypropylene carbonate, polyglycolide, poly(lactide-co-glycolide), polycaprolactone, polydioxan-2-one, polyamino acid, polyortho ester, polyanhydride, polycarbonate, and combinations thereof.

4. The dry formulation for tissue repair of claim 1, wherein the hydrophilic biocompatible polymer is selected from the group consisting of polyethylene glycol (PEG), methoxypolyethylene glycol (mPEG), and combinations thereof, and the hydrophobic biocompatible polymer is selected from the group consisting of polypropylene carbonate, polyglycolide, poly(lactide-co-glycolide), and combinations thereof.

5. The dry formulation for tissue repair of claim 1, wherein the additive is selected from the group consisting of a buffer, a freeze-drying aid, an isotonic agent, or combinations thereof.

6. The dry formulation for tissue repair of claim 5, wherein the buffer is selected from the group consisting of sodium phosphate monobasic (NaH2PO4), sodium phosphate dibasic (Na2HPO4), potassium phosphate monobasic (KH2PO4), potassium phosphate dibasic (K2HPO4), sodium citrate, sodium acetate, sodium bicarbonate, sodium carbonate, or combinations thereof.

7. The dry formulation for tissue repair of claim 5, wherein the freeze-drying aid is one or more selected from the group consisting of lactose, maltose, sucrose, trehalose, mannitol, sorbitol, maltitol, xylitol, and lactitol.

8. The dry formulation for tissue repair of claim 5, wherein the isotonic agent is selected from the group consisting of sodium chloride, potassium chloride, calcium chloride, dextrose, boric acid, or combinations thereof.

9. The dry formulation for tissue repair of claim 1, wherein when the dry formulation is reconstituted in an aqueous medium, the composition thus reconstituted exhibits a shear stress measured 1 hour after reconstitution that is more than 1.5 times the shear stress measured immediately after reconstitution under the same conditions.

10. The dry formulation for tissue repair of claim 1, wherein when the dry formulation is reconstituted in an aqueous medium, the composition thus reconstituted exhibits a shear stress measured 6 hours after reconstitution that is more than 2 times the shear stress measured immediately after reconstitution under the same conditions.

11. A method for preparing a dry formulation for tissue repair, the method comprising the steps of: (1) dissolving or dispersing a biocompatible copolymer and an additive in a mixture of an organic solvent and an aqueous medium, the biocompatible copolymer being a copolymer of a hydrophilic biocompatible polymer and a hydrophobic biocompatible polymer; and (2) drying the product of step (1); wherein when the product of step (2) is reconstituted in an aqueous medium, the composition thus reconstituted exhibits thixotropy with increasing viscosity over time.

12. The method for preparing a dry formulation for tissue repair of any one of claims 11, wherein the organic solvent is one or more selected from the group consisting of a ketone-based solvent, an alcohol-based solvent, a sulfone-based solvent, a nitrile-based solvent, an ether-based solvent, an amide-based solvent, an alkane-based solvent, and combinations thereof.

13. An injectable composition for tissue repair, the injectable composition for tissue repair comprising: a dry formulation for tissue repair of any one of claims 1-10; and a pharmaceutically acceptable carrier for injection.

14. The injectable composition for tissue repair of claim 13, wherein the dry formulation for tissue repair or the carrier for injection comprises a local anesthetic.

15. The injectable composition for tissue repair of claim 13, further comprising one or more components selected from the group consisting of a polynucleotide fraction, a polynucleotide fragment, a biocompatible polymer, or combinations thereof.

16. A method for preparing an injectable composition for tissue repair, the method comprising: mixing a dry formulation for tissue repair of any one of claims 1-10 with a pharmaceutically acceptable carrier for injection.

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