Patent Application
20220008332
The present invention relates to a microneedle array and a method of producing the same. The present invention particularly relates to a microneedle array containing influenza vaccine and a method of producing the same.
Influenza is an acute infectious respiratory disease caused by influenza viruses that spread through respiratory droplet infection. Influenza vaccination is considered to be effective in preventing influenza, but the effectiveness is not satisfactory.
In recent years, a method of administering influenza vaccine using a microneedle array has been suggested as an efficient method of administering a vaccine. JP2007-530680A discloses a transdermal delivery device for influenza vaccine and a method of administering influenza vaccine.
A dissolution type microneedle array in which a base material formed of a substance that can be dissolved in a living body contains a drug has been developed. Since needles of a microneedle array are thin and short, stimulation to nerves is small. Therefore, a microneedle array is also referred to as a “painless injection”.
JP2007-530680A describes metal microneedles, each surface of which is coated with a vaccine, but there is a concern of safety in terms that the metal microneedles may puncture the skin twice. JP6389559B discloses microneedles forming a dissolution type microneedle array that contains inactivated whole-virion influenza vaccine, but does not disclose natural amino acids.
In the related art, administration of influenza vaccine is performed by subcutaneous and intramuscular injections. However, fear of injection needles, pain during the injection, and mental stress are problems. In order to solve the problems, administration carried out using a microneedle array has been suggested as a method that does not cause pain. In particular, a microneedle array containing a vaccine is expected to improve the effectiveness.
Since a microneedle array is extremely small, the microneedle array is required to have a small volume for containing a drug and contain a drug at a higher concentration than that of an injection. Therefore, the distance between the drugs is decreased, and thus there is a possibility that the aggregation or reaction is likely to occur and the drug is inactivated during the production. In a microneedle array containing influenza vaccine which has been examined by the present inventors, the activity of the influenza vaccine may be impaired during the production, and accordingly, there is a demand for improving the stability of the influenza vaccine during the production.
Further, in a case where there is a part where the drug contained in the microneedle array is not administered in a living body, a large amount of the drug is wastefully consumed. Therefore, the drug needs to be concentrated on the tip of a needle portion in the microneedle array.
An object of the present invention is to provide a microneedle array in which the stability of influenza vaccine during production is satisfactory and the utilization efficiency of the influenza vaccine is high, and a method of producing the same.
As a result of intensive examination conducted by the present inventors in order to achieve the above-described object, it was found that in a case where a microneedle array containing influenza vaccine contains a saccharide, influenza vaccine, a natural amino acid or a salt thereof, and a surfactant, the stability of the influenza vaccine during production is improved and the performance of the influenza vaccine localized at the tips is also improved. The present invention has been completed based on these findings.
That is, according to an aspect of the present invention, the following inventions are provided.
(1) A self-dissolving microneedle array comprising: a sheet portion; and a plurality of needle portions which are present on an upper surface of the sheet portion, in which the needle portion contains a saccharide, influenza vaccine, a natural amino acid or a salt thereof, and a surfactant and the influenza vaccine is administered into a body by dissolution of the needle portions.
(2) The microneedle array according to (1), in which a content of the saccharide contained in the needle portion is 10% by mass or greater and 99% by mass or less with respect to a solid content of the needle portion.
(3) The microneedle array according to (1) or (2), in which the saccharide is at least one selected from hydroxyethyl starch, chondroitin sulfate, or a disaccharide.
(4) The microneedle array according to any one of (1) to (3), in which the natural amino acid is at least one selected from glutamic acid, aspartic acid, lysine, histidine, arginine, glycine, or alanine.
(5) The microneedle array according to any one of (1) to (4), in which the surfactant includes a nonionic surfactant.
(6) The microneedle array according to any one of (1) to (5), in which the influenza vaccine includes HA vaccine.
(7) A method of producing the microneedle array according to any one of (1) to (6), the method comprising: a step of concentrating influenza vaccine; a step of forming needle portions using the concentrated influenza vaccine obtained in the above-described step; and a step of forming a sheet portion.
(8) The method of producing the microneedle array according to (7), in which the step of concentrating influenza vaccine is a step of concentrating influenza vaccine by centrifugation.
In the microneedle array containing influenza vaccine according to the present invention, the stability of the influenza vaccine is satisfactory, and the utilization efficiency of the influenza vaccine is high.
(A) and (B) of
(A) and (B) of
Hereinafter, embodiments of the present invention will be described in detail.
In the present specification, the expression “containing a drug” means that a drug having an amount enough to exhibit drug efficacy is contained in a case of puncturing the body surface. The expression “not containing a drug” means that a drug having an amount enough to exhibit drug efficacy is not contained, and a range of the amount of the drug covers from a case where the drug is not contained at all to a case where the amount thereof is not enough to exhibit the drug efficacy.
In a microneedle array according to the embodiment of the present invention, the stability of influenza vaccine can be improved and the influenza vaccine can be localized at the tip of a needle portion by allowing the needle portion to contain a natural amino acid or a salt thereof. The effect that the stability of the influenza vaccine can be improved and the influenza vaccine can be localized at the tip of the needle portion by allowing the needle portion to contain a natural amino acid or a salt thereof cannot be expected in the related art. Further, the microneedle array according to the embodiment of the present invention is not intended to use the coating type described in JP2007-530680A. That is, the microneedle array according to the embodiment of the present invention is a self-dissolving microneedle array in which a drug is administered into the body by dissolution of the needle portion.
[Configuration of Microneedle Array]
A microneedle array according to the embodiment of the present invention is a microneedle array including a sheet portion, and a plurality of needle portions which are present on an upper surface of the sheet portion, in which the needle portion contains a saccharide, influenza vaccine, a natural amino acid or a salt thereof, and a surfactant. The microneedle array according to the embodiment of the present invention is a self-dissolving microneedle array in which the influenza vaccine which is a drug is administered into the body by dissolution of the needle portions in the body including the body surface in a case where the body surface (including the skin and the like) is punctured by the microneedle array.
In the present invention, plural means one or more.
The microneedle array according to the embodiment of the present invention includes at least a sheet portion and needle portions and a drug is carried by the needle portions in order to efficiently administer the drug into the body.
The microneedle array according to the embodiment of the present invention is a device in which a plurality of needle portions are arranged in an array on the upper surface side of the sheet portion. It is preferable that the needle portions are arranged on the upper surface side of the sheet portion. The needle portions may be arranged directly on the upper surface of the sheet portion or may be arranged on the upper surfaces of frustum portions arranged on the upper surface of the sheet portion.
The sheet portion is a foundation for supporting the needle portions and has a planar shape as the shape of a sheet portion 116 illustrated in
The area of the sheet portion is not particularly limited, but is preferably in a range of 0.005 to 1000 mm2, more preferably in a range of 0.1 to 800 mm2, and still more preferably in a range of 1 to 800 mm2.
The thickness of the sheet portion is a distance between the surface in contact with frustum portions or needle portions and the surface on the opposite side. The thickness of the sheet portion is preferably 1 μm or greater and 2000 μm or less, more preferably 3 μm or greater and 1500 μm or less, and still more preferably 5 μm or greater and 1000 μm or less.
It is preferable that the sheet portion contains a water-soluble polymer. The sheet portion may be formed of a water-soluble polymer or may contain other additives (for example, disaccharides). Further, it is preferable that the sheet portion does not contain a drug.
The water-soluble polymer contained in the sheet portion is not particularly limited, and examples thereof include polysaccharides (such as hyaluronic acid, sodium hyaluronate, pullulan, dextran, dextrin, sodium chondroitin sulfate, carboxymethyl cellulose, hydroxypropyl cellulose, hydroxyethyl starch, hydroxypropyl methyl cellulose, polyvinylpyrrolidone, polyoxyethylene polyoxypropylene glycol, polyethylene glycol, and arabic rubber) and proteins (such as gelatin). The above-described components may be used alone or in the form of a mixture of two or more kinds thereof. Among these, polysaccharides are preferable, hydroxyethyl starch, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, pullulan, dextran, sodium chondroitin sulfate, sodium hyaluronate, carboxymethyl cellulose, polyvinylpyrrolidone, polyoxyethylene polyoxypropylene glycol, polyethylene glycol, and polyvinyl alcohol are more preferable, and chondroitin sulfate, hydroxyethyl starch, and dextran are particularly preferable.
Disaccharides may be added to the sheet portion and examples of the disaccharides include sucrose, lactulose, lactose, maltose, trehalose, and cellobiose. Among these, sucrose, maltose, and trehalose are particularly preferable.
The microneedle array is formed of a plurality of needle portions arranged in an array on the upper surface side of the sheet portion. The needle portions have a projected structure with a tip, and the shape thereof is not limited to a needle shape having a sharp tip and may be a shape with a blunt tip.
Examples of the shape of a needle portion include a conical shape, a polygonal pyramid shape (square pyramid shape or the like), and a spindle shape. For example, a needle portion may have a shape of a needle portion 112 illustrated in any of
In a case where the microneedle array according to the embodiment of the present invention is applied to the body surface (including the skin), it is preferable that the needle portions are inserted into the body surface and the upper surface or a part of the sheet portion is brought into contact with the body surface.
The height (length) of a needle portion indicates the length of a perpendicular line drawn from the tip of the needle portion to the frustum portion or the sheet portion (in a case where a frustum portion is not present). The height (length) of a needle portion is not particularly limited, but is preferably 50 μm or greater and 3000 μm or less, more preferably 100 μm or greater and 1500 μm or less, and still more preferably 100 μm or greater and 1000 μm or less. It is preferable that the length of a needle portion is 50 μm or longer because a drug can be percutaneously administered. Further, it is preferable that the length of a needle portion is 3000 μm or less because occurrence of pain resulting from the contact of needle portions with the nerve is prevented and bleeding can be avoided.
The interface between a frustum portion (or a needle portion in a case where a frustum portion is not present) and the sheet portion is referred to as a base portion. The distance between the farthest points on a base portion of one needle portion is preferably 50 μm or greater and 2000 μm or less, more preferably 100 μm or greater and 1500 μm or less, and still more preferably 100 μm or greater and 1000 μm or less.
The number of needle portions to be arranged in one microneedle array is preferably in a range of 1 to 2000, more preferably in a range of 3 to 1000, and still more preferably in a range of 5 to 500. In a case where one microneedle array includes two needle portions, the interval between needle portions indicates the distance between feet of each perpendicular line drawn from the tip of a needle portion to a frustum portion or the sheet portion (in the case where a frustum portion is not present). In a case where one microneedle includes three or more needle portions, the interval between needle portions to be arranged indicates an average value obtained by acquiring the distance between a foot of a perpendicular line drawn from the tip of a needle portion to a frustum portion or the sheet portion (in the case where a frustum portion is not present) and a foot of a perpendicular line drawn from the tip of a needle portion nearest to the needle portion to a frustum portion or the sheet portion and averaging the values obtained from all needle portions. The interval between needle portions is preferably 0.1 mm or greater and 10 mm or less, more preferably 0.2 mm or greater and 5 mm or less, and still more preferably 0.3 mm or greater and 3 mm or less.
It is preferable that the needle portions contain a saccharide, influenza vaccine, a natural amino acid or a salt thereof, and a surfactant. It is preferable that the saccharide is a substance that can be dissolved in a living body so that trouble does not occur in a human body even in a case where the needle portions remain in the body surface (including the skin).
The saccharide contained in the needle portions is not particularly limited, and examples thereof include polysaccharides (such as hyaluronic acid, sodium hyaluronate, pullulan, dextran, dextrin, sodium chondroitin sulfate, carboxymethyl cellulose, hydroxypropyl cellulose, hydroxyethyl starch, hydroxypropyl methyl cellulose, polyvinylpyrrolidone, polyoxyethylene polyoxypropylene glycol, polyethylene glycol, and arabic rubber) and disaccharides. Examples of the disaccharides include sucrose, lactulose, lactose, maltose, trehalose, and cellobiose. Among these, sucrose, maltose, and trehalose are particularly preferable. The above-described components may be used alone or in the form of a mixture of two or more kinds thereof. Among the examples described above, generally, saccharides having no electric charge are preferable because aggregation is unlikely to occur in a case where such saccharides are mixed with a drug. The saccharides contained in the needle portions may be the same as or different from the water-soluble polymer contained in the sheet portion.
The content of the saccharides contained in the needle portions is preferably 10% by mass or greater and 99% by mass or less, more preferably 30% by mass or greater and 99% by mass or less, and still more preferably 50% by mass or greater and 99% by mass or less with respect to the solid content of the needle portions.
Particularly in a case where disaccharides are selected to be contained in the needle portions, the content of the saccharides contained in the needle portions is preferably in a range of 5 times to 500 times the content of the influenza vaccine and more preferably in a range of 5 times to 100 times the content of the influenza vaccine.
The needle portions contain influenza vaccine as a drug.
The influenza vaccine may contain only one or two or more kinds of virus antigens. In a case where a particular influenza virus is prevalent and a particular strain of vaccine is rapidly produced and supplied, it is preferable that the vaccine contains only one virus antigen. In a case where immunity against a wide range of virus strains is imparted by vaccine administration, it is preferable that the vaccine contains two or more kinds of virus antigens. It is preferable that the influenza vaccine contains an influenza A virus antigen, an influenza B virus antigen, or mixtures thereof. It is more preferable that the influenza vaccine contains an influenza A H1N1 virus antigen, an influenza A H3N2 virus antigen, an influenza B virus antigen, or a mixture thereof. In a case where the influenza vaccine contains two or more kinds of virus antigens, the amount of antigens derived from each virus is not particularly limited, but the influenza vaccine may preferably contain equal amounts of antigens derived from each virus.
The influenza vaccine may be HA vaccine containing hemagglutinin (HA) of influenza viruses or inactivated whole-virion influenza vaccine. It is preferable that the influenza vaccine is HA vaccine containing a hemagglutinin (HA) fraction obtained by treating viral particles with an ether or the like so that the viral particles are decomposed and inactivated. Hemagglutinin is also referred to as hemagglutinin (HA).
The influenza vaccine and the vaccine stock solution may contain a pharmaceutically acceptable carrier as necessary. As the pharmaceutically acceptable carrier, a carrier used to produce a vaccine can be used without limitation, and specifically, saccharides, inorganic salts, buffered saline, dextrose, water, glycerol, isotonic aqueous buffer solutions, surfactants, emulsifiers, preservatives, isotonizing agents, pH adjusters, deactivating agents, and a combination of two or more kinds thereof are appropriately blended.
The influenza vaccine and the vaccine stock solution may contain an immunopotentiator (adjuvant). Examples of the adjuvant include a mineral-containing composition, an oily emulsion, a saponin composition, a virosome, virus-like particles (VLP), and a bacterial or microbial derivative (such as a non-toxic derivative of Enterobacteriaceae lipopolysaccharide, a lipid A derivative, immunostimulatory oligonucleotide ADP ribosylated toxin, or a detoxification derivative thereof).
The content of the influenza vaccine in all the needle portions is not particularly limited, but is preferably in a range of 0.01 μg to 200 μg and more preferably in a range of 1 μg to 100 μg in terms of the content of hemagglutinin (HA) per preparation of the microneedle array.
In the microneedle array according to the embodiment of the present invention, the needle portions contain at least one of a natural amino acid or a salt thereof. The natural amino acid or the salt thereof contained in the needle portions is not particularly limited, and examples thereof include polar amino acids (such as glutamic acid, aspartic acid, lysine, histidine, and arginine), glycine, alanine, and salts thereof. Among these, polar amino acids and salts thereof are preferable. Examples of the salts thereof include salts of sodium, potassium, monoethanolamine, diethanolamine, triethanolamine, and the like. The natural amino acid or the salt thereof may be used alone or in the form of a mixture of two or more kinds thereof.
The content of the natural amino acid or the salt thereof in the needle portions is preferably in a range of 1 time to 150 times the content of the influenza vaccine and more preferably in a range of 1 time to 50 times the content of the influenza vaccine.
In the microneedle array according to the embodiment of the present invention, the needle portions contain a surfactant. The surfactant contained in the needle portions may be any of a nonionic surfactant (an electrically neutral surfactant), a cationic surfactant, an anionic surfactant, or an amphoteric surfactant. Among these, a nonionic surfactant (an electrically neutral surfactant) is preferable.
Examples of the nonionic surfactant include sugar alcohol fatty acid ester such as sucrose fatty acid ester, sorbitan fatty acid esters, glycerin fatty acid ester, polyglycerin fatty acid ester, propylene glycol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyethylene glycol fatty acid ester, a polyoxyethylene/polyoxypropylene copolymer, polyoxyethylene castor oil, polyoxyethylene hydrogenated castor oil, and octylphenol ethoxylate. Among these, sorbitan fatty acid ester, a polyoxyethylene/polyoxypropylene copolymer, or polyoxyethylene hydrogenated castor oil is particularly preferable. As the nonionic surfactant, commercially available products such as Tween (registered trademark) 80, Pluronic (registered trademark) F-68, HCO-60 (polyoxyethylene 60 hydrogenated castor oil), and Triton (registered trademark)-X can also be used.
Examples of the cationic surfactant include a quaternary ammonium compound (such as benzalkonium chloride, cetylpyridinium chloride, benzethonium chloride, or cetyltrimethylammonium bromide), and other trimethylalkylammonium salts.
Examples of the anionic surfactant include salts of perfluorinated carboxylic acid and perfluorinated sulfonic acid, an alkyl sulfate (such as sodium dodecyl sulfate or ammonium lauryl sulfate), ether sulfate (such as sodium lauryl ether sulfate), and an alkylbenzene sulfonate.
Examples of the amphoteric surfactant include dodecyl betaine, cocoamphoglycinate, and cocamidopropyl betaine.
The content of the surfactant is not particularly limited, but is preferably in a range of 0.01 times to 1 time the content of the influenza vaccine and more preferably in a range of 0.01 times to 0.5 times the content of the influenza vaccine.
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited thereto.
The needle portion 112 has a conical shape in
It is preferable that the microneedle array according to the embodiment of the present invention has a shape of the microneedle 110 in
A first layer 112A of the needle portion illustrated in
In the microneedle array according to the embodiment of the present invention, it is preferable that needle portions are arranged at intervals of approximately 0.1 to 10 needles per 1 mm in a row. It is more preferable that the microneedle array has 1 to 10000 microneedles per 1 cm2. In a case where the density of microneedles is set to 1 needle/cm2 or greater, the microneedles can efficiently puncture the skin. Further, in a case where the density of the microneedles is set to 10000 needles/cm2 or less, the microneedle array can sufficiently puncture the skin. The density of needle portions is preferably in a range of 10 to 5000 needles/cm2, more preferably in a range of 25 to 1000 needles/cm2, and particularly preferably in a range of 25 to 400 needles/cm2.
The microneedle array according to the embodiment of the present invention can be supplied in a sealed storage form together with a drying agent. As the drying agent, known drying agents (such as silica gel, calcined lime, calcium chloride, silica alumina, and a sheet-like drying agent) can be used.
[Method of Producing Microneedle Array]
According to the present invention, there is provided a method of producing the microneedle array according to the embodiment of the present invention, including a step of concentrating influenza vaccine, a step of forming needle portions using the concentrated influenza vaccine obtained in the above-described step, and a step of forming a sheet portion.
It is preferable that the step of concentrating the influenza vaccine is a step of concentrating the influenza vaccine by centrifugation.
The microneedle array according to the embodiment of the present invention can be produced in conformity with the methods described in, for example, JP2013-153866A or WO2014/077242A.
In the present invention, the needle portions can be formed by, for example, filling a mold (die) with a liquid containing saccharides, influenza vaccine, a natural amino acid or a salt thereof, and a surfactant. Hereinafter, a method of producing a microneedle array, including forming needle portions by filling a mold (die) will be described, but the microneedle array according to the embodiment of the present invention is not limited to this production method, and a known method of producing a self-dissolving microneedle array can be applied.
(Preparation of Mold)
According to the first method, a Si substrate is coated with a photoresist, exposed, and then developed. Further, an array of shaped portions 12 having a conical shape (projection) is prepared on the surface of the original plate 11 by performing etching using reactive ion etching (RIE) or the like. In a case where the etching such as RIE or the like is performed so as to form shaped portions having a conical shape on the surface of the original plate 11, the portions having a conical shape can be formed by performing etching in an oblique direction while the Si substrate rotates. According to the second method, an array of the shaped portions 12 having a square pyramid shape or the like is formed on the surface of the original plate 11 by performing processing on a metal substrate such as Ni using a cutting tool such as a diamond bit.
Next, a mold is prepared. Specifically, a mold 13 is prepared using the original plate 11 as illustrated in
According to the first method, a silicone resin obtained by adding a curing agent to polydimethylsiloxane (PDMS, for example, SYLGARD 184 (registered trademark, manufactured by Dow Corning Toray Co., Ltd.)) is poured into the original plate 11, subjected to a heat treatment at 100° C., cured, and peeled off from the original plate 11. According to the second method, an ultraviolet (UV) cured resin which is cured by being irradiated with ultraviolet rays is poured into the original plate 11, irradiated with ultraviolet rays in a nitrogen atmosphere, and peeled off from the original plate 11. The third method is a method of pouring a solution obtained by dissolving a plastic resin such as polystyrene or polymethyl methacrylate (PMMA) in an organic solvent into the original plate 11 coated with a peeling agent, drying the solution so that the organic solvent is volatilized and the resin is cured, and peeling off the cured resin from the original plate 11. According to the fourth method, an inverted product is produced using Ni electroforming.
In this manner, the mold 13 formed by needle-like recesses 15, which have an inverted shape of the conical shape or the pyramid shape of the original plate 11, being two-dimensionally arranged is prepared. The mold 13 prepared in the above-described manner is illustrated in
(A) and (B) of
As illustrated in the (A) portion of
In a case where such a mold complex 18 is used, only the air present in the needle-like recess 15 can be released from the needle-like recess 15 without permeation of the dissolved solution containing a component that forms a needle portion, which is added to the needle-like recess 15. In this manner, the property of transferring the shape of the needle-like recess 15 to a polymer is excellent and a sharper needle portion can be formed.
A diameter D of the air vent hole 15C is preferably in a range of 1 to 50 μm. In a case where the diameter D of the air vent hole 15C is less than 1 μm, the air vent hole 15C cannot be sufficiently used as an air vent hole. Further, in a case where the diameter D of the air vent hole 15C is greater than 50 μm, the sharpness of the tip of a formed microneedle is damaged.
As the gas permeating sheet 19 formed of a material that permeates a gas and does not permeate a liquid, for example, a gas permeating film (POREFLON (registered trademark), FP-010, manufactured by Sumitomo Electric Industries, Ltd.) can be suitably used.
As the material used for the mold 13, an elastic material or a metal material can be used. Among these, an elastic material is preferable and a material having a high gas permeability is more preferable. The oxygen permeability, which is a representative example of the gas permeability, is preferably 1×10−12 (mL/s·m2·Pa) or greater and more preferably 1×10−10 (mL/s·m2·Pa) or greater. Further, 1 mL is 10−6 m3. In a case where the gas permeability is in the above-described range, the air present in a recess of the mold 13 can be released from the mold and a microneedle array with less defects can be produced. Specific examples of such materials include materials obtained by melting or dissolving, in a solvent, a silicone resin (for example, SYLGARD 184 (registered trademark, manufactured by Dow Corning Toray Co., Ltd.) or KE-1310ST (product number, manufactured by Shin-Etsu Chemical Co., Ltd.)), a UV curable resin, or a plastic resin (for example, polystyrene or polymethyl methacrylate (PMMA)). Among these, a silicone rubber-based material is preferable since the material has durability to transfer resulting from repetitive pressure and has excellent peeling properties with respect to a material. Further, examples of the metal material include Ni, Cu, Cr, Mo, W, Ir, Tr, Fe, Co, MgO, Ti, Zr, Hf, V, Nb, Ta, α-aluminum oxide, zirconium oxide, stainless steel (for example, STAVAX (trademark), manufactured by Bohler-Uddeholm KK), and alloys thereof. As the material of a frame, the same material as the material of the mold 13 can be used.
(Influenza Vaccine-Containing Dissolved Solution and Water-Soluble Polymer-Dissolved Solution)
In the present invention, it is preferable to prepare a dissolved solution containing a component that forms a needle portion containing influenza vaccine (influenza vaccine-containing dissolved solution), which is used for forming at least a part of a needle portion, and a water-soluble polymer-dissolved solution used for forming the sheet portion.
Disaccharides may be mixed into the water-soluble polymer-dissolved solution used for forming the sheet portion, and the kind of the disaccharides is as described in the present specification above.
Further, the solvent used for dissolution may be a solvent other than water as long as the solvent has volatility, and methyl ethyl ketone (MEK) or an alcohol can be used as the solvent.
Specifically, the dissolved solution containing a component that forms a needle portion (influenza vaccine-containing dissolved solution), which is used for forming at least a part of a needle portion, is a liquid containing influenza vaccine, saccharides, a natural amino acid and a salt thereof, and a surfactant.
The concentration of the influenza vaccine in the liquid containing influenza vaccine, saccharides, a natural amino acid and a salt thereof, and a surfactant is not particularly limited, but is preferably in a range of 0.001 mg/mL to 100 mg/mL and more preferably in a range of 0.01 mg/mL to 20 mg/mL.
The concentration of the saccharides in the liquid containing influenza vaccine, saccharides, a natural amino acid and a salt thereof, and a surfactant is not particularly limited, but is preferably in a range of 0.005 mg/mL to 200 mg/mL and more preferably in a range of 0.5 mg/mL to 200 mg/mL.
The concentration of the natural amino acid in the liquid containing influenza vaccine, saccharides, a natural amino acid and a salt thereof, and a surfactant is not particularly limited, but is preferably in a range of 0.003 mg/mL to 200 mg/mL and more preferably in a range of 0.03 mg/mL to 200 mg/mL.
The concentration of the surfactant in the liquid containing influenza vaccine, saccharides, a natural amino acid and a salt thereof, and a surfactant is not particularly limited, but is preferably in a range of 0.00001 mg/mL to 50 mg/mL and more preferably in a range of 0.0001 mg/mL to 10 mg/mL.
(Formation of Needle Portion)
As illustrated in
As the material used for the nozzle 34, an elastic material or a metal material can be used. Examples thereof include TEFLON (registered trademark), stainless steel (steel special use stainless (SUS)), and titanium.
As illustrated in
In a case where the mold 13 is formed of a material having a gas permeability, the influenza vaccine-containing dissolved solution 22 can be sucked from the rear surface of the mold 13, and the filling of the needle-like recesses 15 with the influenza vaccine-containing dissolved solution 22 can be promoted.
Next to the filling step of
Since the movement is made while the lip portion 34A of the nozzle 34 is brought into contact with the surface of the mold 13, the influenza vaccine-containing dissolved solution 22 remaining on the surface of the mold 13 other than the needle-like recesses 15 can be collected by the nozzle 34. It is possible to prevent the influenza vaccine-containing dissolved solution 22 from remaining on a place other than the needle-like recesses 15 of the mold 13.
In order to reduce the damage to the mold 13 and suppress deformation due to compression of the mold 13 as much as possible, it is preferable that the pressing pressure of the nozzle 34 against the mold 13 is set to be as small as possible during the movement. Further, in order to prevent the influenza vaccine-containing dissolved solution 22 from remaining on a place other than the needle-like recesses 15 of the mold 13, it is desirable that at least one of the mold 13 or the nozzle 34 is formed of a flexible material which can be elastically deformed.
By repeating the filling step of
The filling step and the moving step described above may be carried out by (1) filling the needle-like recesses 15 with the influenza vaccine-containing dissolved solution 22 while moving the nozzle 34 or by (2) temporarily stopping the nozzle 34 on the needle-like recesses 15 during the movement of the nozzle 34 to fill the needle-like recesses 15 with the influenza vaccine-containing dissolved solution 22 and moving the nozzle 34 again after the filling. The lip portion 34A of the nozzle 34 is brought into contact with the surface of the mold 13 between the filling step and the moving step.
In a case where the filling of the plurality of needle-like recesses 15 which are formed of 5 rows and 5 columns of needle-like recesses is completed, the nozzle 34 is moved to the plurality of adjacent needle-like recesses 15 which are formed of 5 rows and 5 columns of needle-like recesses. In regard to the liquid supply, it is preferable that the supply of the influenza vaccine-containing dissolved solution 22 is stopped in a case where the nozzle 34 is moved to the plurality of adjacent needle-like recesses 15 which are formed of 5 rows and 5 columns of needle-like recesses. There is a distance between the needle-like recesses 15 in the fifth row and the needle-like recesses 15 in the next first row. While the nozzle 34 is moved therebetween, in a case where the influenza vaccine-containing dissolved solution 22 is continuously supplied, the liquid pressure in the nozzle 34 may be extremely increased. As a result, the influenza vaccine-containing dissolved solution 22 may flow out of the needle-like recesses 15 of the mold 13 from the nozzle 34. In order to suppress this flowing out, it is preferable that the supply of the influenza vaccine-containing dissolved solution 22 is stopped in a case where the liquid pressure in the nozzle 34 is detected and the liquid pressure is determined to be extremely high.
Hereinbefore, the method of supplying the influenza vaccine-containing dissolved solution using a dispenser that has a nozzle has been described, but bar coating, spin coating, spray coating, or the like can be applied in addition to the coating using a dispenser.
In the present invention, it is preferable that a drying treatment is performed after the supply of the influenza vaccine-containing dissolved solution to the needle-like recesses. That is, it is preferable that the method of producing the microneedle array according to the embodiment of the present invention includes a drying step of drying the influenza vaccine-containing dissolved solution after the filling step of filling the mold with the influenza vaccine-containing dissolved solution.
Further, it is preferable that the method of producing the microneedle array according to the embodiment of the present invention includes a step of coating the mold after the drying step with the water-soluble polymer-dissolved solution. After this step, the sheet portion can be formed by drying the applied water-soluble polymer-dissolved solution. That is, as one preferred example of the method of producing the microneedle array according to the embodiment of the present invention, a method including a step of drying a mold for forming needle portions filled with an influenza vaccine-containing dissolved solution to form a part of the needle portions; and a step of filling the upper surfaces of the part of the needle portions which have been formed in the above-described manner with a water-soluble polymer-dissolved solution and drying the mold can be exemplified.
It is preferable that the condition for drying the mold for forming needle portions filled with the influenza vaccine-containing dissolved solution is set to be a condition that the water content of the influenza vaccine-containing dissolved solution reaches 20% or less after 30 to 300 minutes from the start of the drying of the mold.
It is particularly preferable that the drying can be controlled such that the temperature is held to be lower than or equal to a temperature at which the drug does not lose the effect and the water content of the influenza vaccine-containing dissolved solution reaches 20% or less after 60 minutes or longer from the start of the drying of the mold.
As a method of controlling the drying rate, any method of delaying the drying, such as the temperature, the humidity, the drying air volume, the use of a container, and the volume and/or the shape of a container, can be employed.
It is preferable that the drying can be performed in a state where the mold for forming needle portions filled with the influenza vaccine-containing dissolved solution is covered with a container or accommodated in a container.
The temperature during the drying is preferably in a range of 1° C. to 45° C. and more preferably in a range of 1° C. to 40° C.
The relative humidity during the drying is preferably in a range of 10% to 95%, more preferably in a range of 20% to 95%, and still more preferably in a range of 30% to 95%.
(Formation of Sheet Portion)
Several embodiments of a step of forming the sheet portion will be described.
A first embodiment of a step of forming the sheet portion will be described with reference to
In the first embodiment, in order to promote the filling of the needle-like recesses 15 with the influenza vaccine-containing dissolved solution 22 and the water-soluble polymer-dissolved solution 24, it is preferable to apply a pressure from the surface of the mold 13 and perform suctioning from the rear surface of the mold 13 under reduced pressure.
Next, a second embodiment will be described with reference to
In the second embodiment, in order to promote the filling of the needle-like recesses 15 with the water-soluble polymer-dissolved solution 24, it is also preferable to apply a pressure from the surface of the mold 13 and perform suctioning from the rear surface of the mold 13 under reduced pressure.
The method of drying the water-soluble polymer-dissolved solution 24 is not limited as long as the method includes a step of volatilizing the solvent in the polymer-dissolved solution. The method is not particularly limited, and a method of performing heating, blowing air, or decompression may be used. The drying treatment can be performed under the conditions of 1° C. to 50° C. for 1 to 72 hours. Examples of the method of blowing air include a method of blowing hot air at 0.1 to 10 m/sec. It is preferable that the drying temperature is set as a temperature at which the influenza vaccine contained in the influenza vaccine-containing dissolved solution 22 is not thermally deteriorated.
(Peeling)
A method of peeling the microneedle array from the mold 13 is not particularly limited. It is preferable that needle portions are not bent or broken during the peeling. Specifically, a sheet-like base material 40 on which a pressure-sensitive adhesive layer is formed is attached onto the microneedle array and then the base material 40 can be peeled off from the end portion such that the base material 40 is turned over as illustrated in
The method of producing the microneedle array according to the embodiment of the present invention is not particularly limited, but it is preferable that the microneedle array is obtained by a production method including a step (1) of producing a mold, a step (2) of preparing an influenza vaccine-containing dissolved solution, a step (3) of filling the mold with the solution obtained in the step (2) to form upper end portions of the needle portions, a step (4) of filling the mold with a water-soluble polymer-dissolved solution to form lower end portions of the needle portions and a sheet portion, and a step (5) of peeling the microneedle array from the mold.
Hereinafter, the present invention will be described in more detail with reference to examples of the present invention. Further, the materials, the use amounts, the ratios, the treatment contents, the treatment procedures, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be limitatively interpreted by the specific examples described below.
The abbreviations and the trade names in the examples are as follows.
<Preparation of Microneedle Array Containing Influenza Vaccine>
(Production of Mold)
An original plate 11 was prepared by arranging shaped portions 12 having a needle-like structure, on which a cone 52 with a diameter D2 of 340 μm and a height H2 of 834 μm was formed on a truncated cone 50 having a bottom surface with a diameter D1 of 800 μm and having a height H1 of 200 μm, on the surface of a smooth Ni plate having one side with a length of 40 mm, as illustrated in (A) and (B) of
(Preparation of Influenza Vaccine Concentrated Solution)
The influenza vaccine (HA vaccine) stock solution was poured into a container for exclusive use for ultracentrifugation, and the influenza vaccine was allowed to be precipitated by ultracentrifugation (conditions: 131,491×g, 90 minutes, 4° C.). The supernatant was disposed of, phosphate buffered saline (PBS) was added thereto so that the mixture was vortexed, and the resultant was allowed to stand at 4° C. overnight, thereby preparing an influenza vaccine concentrated solution.
(Preparation of Influenza Vaccine-Containing Dissolved Solution)
An aqueous solution obtained by mixing the influenza vaccine concentrated solution, saccharides, a natural amino acid or a salt thereof, and a surfactant was prepared as a water-soluble polymer-dissolved solution containing the influenza vaccine. The formulation of each dissolved solution is as listed in Tables 1 and 2. Further, “%” in Tables 1 and 2 indicates % by mass.
(Preparation of Water-Soluble Polymer-Dissolved Solution Forming Sheet Portion)
Chondroitin sulfate (Maruha Nichiro Corporation) or hydroxyethyl starch (Fresenius Kabi AG) was dissolved in water to prepare a water-soluble polymer-dissolved solution forming a sheet portion. Each dissolved solution was prepared such that the content of CS was 39% by mass and the content of HES was 56% by mass.
(Filling and Drying of Influenza Vaccine-Containing Dissolved Solution)
A filling device illustrated in
A gas permeating film having one side with a length of 15 mm (POREFLON (registered trademark), FP-010, Sumitomo Electric Industries, Ltd.) was placed on a horizontal suction stand, and a mold was placed on the film such that the surface of the mold was directed to the upper side. The gas permeating film and the mold were fixed to the vacuum stand by reducing the pressure with a suction pressure of a gauge pressure of 90 kPa in the rear surface direction of the mold.
A stainless steel (SUS) nozzle having a shape as illustrated in
The mold filled with the influenza vaccine-containing dissolved solution was allowed to stand in an environment of a temperature of 23° C. and a relative humidity of 45% and dried.
(Formation and Drying of Sheet Portion)
The water-soluble polymer-dissolved solution forming the sheet portion was developed on the mold suctioning the solution in a state where the mold filled with the influenza vaccine-containing dissolved solution was placed on a vacuum stand and sucked under reduced pressure. The suction was stopped 60 minutes after the development of the water-soluble polymer-dissolved solution, and the mold was allowed to stand in an environment of a temperature of 23° C. and a relative humidity of 45% and dried.
(Peeling)
The dried and solidified microneedle array was carefully peeled off from the mold to form a microneedle array containing influenza vaccine. Each microneedle is formed of a frustum portion and a needle portion. The height of a needle portion is approximately 800 μm and the width of a base portion is approximately 320 μm, and the frustum portion has a truncated cone structure such that the height thereof is approximately 160 μm, the diameter of the upper bottom surface thereof is approximately 320 μm, and the diameter of the lower bottom surface thereof is approximately 780 μm. The thickness of the sheet portion is approximately 200 μm, the number of needles is 100, the interval between needles is approximately 1 mm, and the needles are arranged in a square shape.
<Evaluation of Microneedle Array>
(Vaccine Recovery Rate in Needle Tip Region of Microneedle)
(a) Content in Microneedle from Needle Tip to 600 μm
Each needle portion of a microneedle having a needle length of 800 μm was cut at a position of 600 μm from the needle tip using a cutter blade (see
According to the examples of the present invention, the vaccine content was 60% or greater of the expected content, the stability of the influenza vaccine during the production was satisfactory and the utilization efficiency of the influenza vaccine was high.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2019-062947 | Mar 2019 | JP | national |
This application is a Continuation of PCT International Application No. PCT/JP2020/013906 filed on Mar. 27, 2020, which claims priority under 35 U.S.C § 119(a) to Japanese Patent Application No. 2019-062947 filed on Mar. 28, 2019. Each of the above application(s) is hereby expressly incorporated by reference, in its entirety, into the present application.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2020/013906 | Mar 2020 | US |
| Child | 17486137 | US |
