JP2013042915A - Bioabsorbable polymer stent containing medicine and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stent which is excellent in a medicine sustained release property, bioabsorbability and form retainability and is configured from a molding obtained by melting and molding bioabsorbable polymers containing a medicine.SOLUTION: This stent is made of the molding obtained by melting and molding the bioabsorbable polymers. The bioabsorbable polymer is a crystalline polymer having a melting point of 90°C or above. In the stent and a method for producing the stent, the stent is formed by melting and molding a composition containing the bioabsorbable polymer and the medicine having a decomposition temperature of 100°C or above. Preferably, the bioabsorbable polymer is polylactic acid having L forms ≥90% and D forms ≤10%, and preferably, the medicine is argatroban.

Description

  The present invention relates to a bioabsorbable polymer tube containing a drug that is effective in improving stenosis or occlusion in a living body lumen such as a blood vessel, bile duct, trachea, esophagus, urethra, etc. The present invention relates to a configured stent and a method for manufacturing the same.

Conventionally, a stent is manufactured by forming a predetermined mesh pattern by laser processing a metal tube. In some cases, a stent is further coated with a polymer containing a drug. This stent is placed in the living body and used for treatment. However, once a metal stent is placed in the living body, it stays at the placement site semi-permanently. It has been pointed out that there is a possibility that it may not be appropriate to place it in a living body semipermanently. From the above, recently, attempts have been made to obtain a stent having a predetermined shape from a bioabsorbable polymer fiber obtained by melt spinning a biodegradable polymer (Patent Document 1).
In Patent Document 1, after forming a tubular body from a high-melting-point bioabsorbable polymer fiber such as polylactic acid, a low-melting-point bioabsorbable polymer such as poly-ε-caprolactone containing a drug is added to the tubular body. Coating (Example 5), or forming a tubular body with twin yarns of a high melting point bioabsorbable polymer fiber and a low melting point bioabsorbable polymer fiber containing a drug (Example 2), or A tubular body is composed of a high melting point bioabsorbable polymer fiber, and a drug-containing low melting point bioabsorbable polymer fiber is entangled around the tubular body (Example 4).

WO96 / 11720 publication

In order to construct a tubular body from the bioabsorbable polymer fiber disclosed in Patent Document 1, it is necessary to form a tubular body while entwining monofilaments or multifilaments together. Therefore, from the bioabsorbable polymer fiber, There is a problem that it is not easy to form a predetermined mesh pattern and to form a tubular body having stable shape retention.
Therefore, the present inventor makes the bioabsorbable polymer contain a drug, does not form a fiber from the drug-containing bioabsorbable polymer, forms a tube-like product, and forms a mesh pattern on the tube-like product after molding. If a stent can be manufactured by forming, it was considered that a drug-containing bioabsorbable polymer stent can be obtained under an efficient process, and a stent that overcomes the disadvantages of the prior art can be provided.

Therefore, the first problem of the present invention is that a bioabsorbable polymer containing a drug is formed into a tube shape, and the formed tube is subjected to laser processing to form a predetermined mesh pattern. Thus, it is to provide a stent having appropriate drug sustained release, moderate bioabsorbability, and shape retention.
The second object of the present invention is to provide a method for producing the above-mentioned stent.

  Said 1st subject is a stent which consists of a molded object which melt-molded the bioabsorbable polymer (A) in the tube shape, The said bioabsorbable polymer (A) is crystalline polymer whose melting | fusing point is 90 degreeC or more. This is solved by providing a stent characterized by melt-molding a composition containing the bioabsorbable polymer (A) and a drug (X) having a decomposition temperature of 100 ° C. or higher.

In the stent described above, the bioabsorbable polymer (A) preferably has a melting point of 110 ° C. or higher and a decomposition temperature of the drug (X) of 120 ° C. or higher.
In the above stent, the bioabsorbable polymer (A) is preferably a crystalline polymer having a glass transition temperature of 40 ° C. or higher.
Furthermore, in the above stent, the bioabsorbable polymer (A) is polylactic acid, and in the polylactic acid, the ratio of L-form to D-form (D / L ratio) is 10/90 to 0/100 ( (Mass ratio).

In the above stent, the drug (X) is preferably argatroban, and the drug (X) is preferably mixed with the bioabsorbable polymer (A) in a particle size of 30 μm or less. Moreover, it is preferable that the said chemical | medical agent (X) is contained in 100 ppm-30 weight part with respect to 100 weight part of said bioabsorbable polymers (A).
In the above-described stent, the molded body preferably has a sea-island structure in which the bioabsorbable polymer (A) is the sea and the drug (X) is an island.

  The stent preferably has a multilayer structure in which a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube. In the bioabsorbable polymer (B) and the bioabsorbable polymer (A), the drug (Y) and the drug (X) may be the same or different from each other.

The second subject is a stent manufacturing method in which the bioabsorbable polymer (A) is melt-molded into a tube shape and processed so as to form a predetermined pattern in the obtained tube-shaped molded body.
Production of a stent characterized by mixing a bioabsorbable polymer (A), which is a crystalline polymer having a melting point of 90 ° C. or higher, with a drug (X) having a decomposition temperature of 100 ° C. or higher and melt-molding it into a tube shape. It is solved by providing a method.

In the stent manufacturing method, it is preferable that a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube by coextrusion to form a multilayer structure.
In the above-described stent manufacturing method, it is preferable that a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube by coating to form a multilayer structure.
The bioabsorbable polymer (B) and the bioabsorbable polymer (A) may be the same or different from the drug (Y) and the drug (X). Good.

  Since the stent obtained by the present invention contains a drug in the stent body, the drug can be gradually released in vivo, so that a therapeutic effect can be exhibited over a long period of time. And since the bioabsorbable polymer which comprises a stent main body lose | disappears gradually in_vivo | within _______________________________ when the drug is released, there is no harmful effect on the living body.

  Furthermore, since a crystalline polymer having a melting point of 90 ° C. or higher is used as the bioabsorbable polymer constituting the stent body in the present invention, it has excellent shape retention compared to a stent formed from a bioabsorbable polymer that is not so. Therefore, it can be placed in the living body and withstand long-term use. Although the bioabsorbable polymer has a melting point of 90 ° C. or lower, it is easier to form a tube by mixing the drug. However, the bioabsorbable polymer having a melting point of 90 ° C. or lower, particularly 60 ° C. or lower, has a mechanical strength ( Since the Young's modulus is low and the shape retention in the living body may be insufficient, it is not used as a polymer for forming the stent body.

  As a drug contained in the bioabsorbable polymer forming the stent body, a crystalline polymer composition having a melting point of 90 ° C. or higher mixed with a drug by using a heat-resistant drug having a decomposition temperature of 100 ° C. or higher. From this, a stent can be produced by melt molding. Among them, argatroban having an effect of suppressing intimal thickening without inhibiting the proliferation of endothelial cells is preferably used as a heat-resistant drug. When such a drug is mixed with a bioabsorbable polymer, it is uniformly distributed in the bioabsorbable polymer by mixing it as a fine powder of 30 μm or less, and uniform sustained release and a structure as a structure throughout the stent. Mechanical strength can be achieved.

  According to the method for manufacturing a stent of the present invention, a tube having a predetermined diameter is formed by heating and melting a composition containing a bioabsorbable polymer and a drug, and a predetermined mesh pattern is formed by laser processing the tube. Can be manufactured, the manufacturing process is simple, and the stent can be easily manufactured from a bioabsorbable polymer. A stent having various specifications can be formed by applying the same technique as that for forming a stent from a metal tube.

It is a top view which shows an example of the shape of the stent which concerns on this invention.

(Stent)
The stent of the present invention can be applied to various biological ducts such as blood vessels, trachea, digestive tract, urinary tract, oviduct, bile duct, etc., and can be used for insertion and placement in the biological duct. Preferably, it is suitable for insertion into a blood vessel such as a blood vessel or a lymphatic vessel, more preferably a blood vessel such as a coronary artery.
The stent may be either a self-expanding type or a balloon-expanding type, but is preferably a balloon-expanding type. Here, the self-expanding stent is inserted into the body in a reduced diameter state by being accommodated in a holding body such as a tube, and when the holding body is pulled out at the attachment site, The thing of the form which ensures the lumen | bore of a biological duct by being expanded in diameter. On the other hand, a balloon-expandable stent is mounted in a state where the diameter is reduced on the outer surface of the balloon and then inserted into the body together with the balloon. A form that secures the lumen of the duct.
In the present invention, the stent can be obtained by molding a bioabsorbable polymer into a tube shape by melt molding as described below, and forming a predetermined mesh pattern by laser processing of the obtained tube.

  Although the stent thus obtained has a single layer structure, in the present invention, the molded product formed into the tube shape is used as a main layer, and the tube is formed by coextrusion at the time of forming the tube. An inner layer and / or an outer layer may be formed on one side or both sides to form a multilayer structure, and the molded product formed into the above-mentioned tube shape is used as a main layer, and coating is applied to one side or both sides of the tube. Thus, an inner layer and / or an outer layer may be formed to form a multilayer structure.

(Bioabsorbable polymer)
In the present invention, the bioabsorbable polymer used to form the stent body (main layer) needs to be a heat-meltable bioabsorbable polymer.
As used herein, bioabsorbable means biodegradable, biodegradable and / or bioabsorbable, and usually the bioabsorbable polymer is preferably within 3 years, more preferably Within two years, it is degraded or dissolved in the living body and absorbed by the living body.
The bioabsorbable polymer used for forming the main layer in the present invention is a crystalline polymer having a melting point of 90 ° C. or higher (preferably 110 ° C. or higher). An environment where a stent is used in a living body, that is, a stent supporting a biological duct wall, is constantly subjected to a radial contraction pressure and a longitudinal stretching force from the pipe wall under body temperature and humidity. Therefore, the bioabsorbable polymer needs to be a crystalline polymer from the viewpoint of shape retention as a stent.
In the present invention, the crystallinity of a polymer refers to a material showing heat of fusion in a thermal analysis method such as a differential scanning calorimeter (DSC).

  The bioabsorbable polymer used for forming the main layer in the present invention is not particularly limited as long as it is a bioabsorbable polymer having a melting point of 90 ° C. or higher, and any bioabsorbable polymer may be used. In the case of a balloon expandable stent, a polymer having a glass transition temperature of 40 ° C. or higher, more preferably 50 ° C. or higher is preferable.

  Crystalline polymers having a melting point of 90 ° C. or higher and a glass transition temperature of 40 ° C. or higher used in the present invention include poly (L-lactic acid) and poly (D-lactic acid) (both melting points: 170 to 190 ° C. , Glass transition temperature: 50 to 65 ° C .; poly (DL-lactic acid) (D / L: 7/93) (melting point: 153 ° C., glass transition temperature: 64 ° C.) / L ratio) in the range of 10/90 to 0/100 and 90/10 to 100/0 by mass ratio; poly (lactic acid (L) -glycolic acid (G)) copolymer (L / G: 85/15) (melting point: 140-150 ° C., glass transition temperature: 55 ° C.) and poly (lactic acid (L) -glycolic acid (G)) copolymer (L / G: 10/90) (melting point : 202-210 ° C, glass transition temperature: 42 ° C), etc. Copolymerization of poly (lactic acid-glycolic acid) in which the copolymerization ratio of oxalic acid (G) is L / G = 80-100 / 20-0 or 20-0 / 80-100 in terms of mass ratio Examples include coalescence.

  As crystalline bioabsorbable polymers having a melting point of 90 ° C. or more and a glass transition temperature of 40 ° C. or less, polyglycolic acid (melting point: 230 ° C., glass transition temperature: 36 ° C.), poly (lactic acid (L) -ε -Caprolactone (C)) copolymer (L / C: 70/30) (melting point: 105-115 ° C, glass transition temperature: 20 ° C), polyhydroxybutyrate (melting point: 180 ° C, glass transition temperature: 4- 40 ° C), poly (lactic acid-ε-caprolactone) (melting point: 60 ° C, glass transition temperature: -60 ° C), polydioxanone (melting point: 106 ° C, glass transition temperature: -10 to 0 ° C), poly (glycolic acid ( G) -trimethylene carbonate (T)) (G / T: 9/1) (melting point: 190 ° C., glass transition temperature: 20 ° C. or less), polybutylene succinate (melting point: 110 ° C., glass transition temperature: − 40 ℃) And polyethylene succinate (melting point: 100 ° C., glass transition temperature: −11 ° C.) and the like, and these bioabsorbable polymers are also used in the present invention.

  A bioabsorbable polymer having a melting point of less than 90 ° C has a possibility of plastic deformation under an unweighted condition and / or a weight that supports a blood vessel in a temperature range below the body temperature due to insufficient mechanical strength. Therefore, it is not preferable. Examples of the polymer having a melting point of less than 90 ° C. include poly-ε-caprolactone and poly (DL lactic acid-ε-caprolactone). In the present invention, these polymers cannot be used as a polymer for forming the main layer of the stent, but as will be described later, a bioabsorbable polymer for forming the inner layer or the outer layer by coextrusion or coating. Can be used.

As described above, the mixing ratio (D / L ratio) of the L-form and D-form of polylactic acid is preferably 10/90 to 0/100 or 90/10 to 100/0 in terms of mass ratio. When the D-form is mixed with the body in an amount of 10% by mass or more, or the D-form is mixed with the L-form in an amount of 10% by mass or more, the polylactic acid becomes amorphous and the form retainability is not sufficient, so it is not used in the present invention.
Poly (DL-lactic acid) (D / L: 50/50), poly (lactic acid (L) -glycolic acid (G)) copolymer (L / G: 50/50), etc. are amorphous. As such, it is not used in the present invention.

(Drug)
In the present invention, the drug used by being mixed with the bioabsorbable polymer forming the main layer is a drug having a decomposition temperature of 100 ° C. or higher (preferably 120 ° C. or higher) because the polymer is melted by heat. A typical example is argatroban [(2R, 4R)-, which is disclosed in JP 2010-264253 A, and has an effect of suppressing the intimal thickening without inhibiting the proliferation of endothelial cells. 4-methyl ^{-1- [N 2 - (RS)} -3- methyl-1,2,3,4-tetrahydro-8-quinoline-sulfonyl) -L- arginyl] -2-piperidinecarboxylic acid hydrate] (decomposition Temperature: 180-220 ° C).

In addition to the above drugs, the drugs used in the present invention include zymegatran, megatran, dabigatran, dabigatran etexylate metasulfonate, gabexate mesylate [ethyl-4- (6-guanidinohexanoyloxy) having protease inhibitory effect. ) Benzoate methanesulfonate], nafamostat mesylate (6-amidino-2-naphthyl p-guanidinobenzoate dimethanesulfonate), dipyridamole (2,6-bis (diethanolamino) -4,8-dipiperidinopyrimido ( 5,4-d) pyrimidine], trapidyl (7-diethylamino-5-methyl-s-triazolo [1,5-a] pyrimidine) and the like are high in heat resistance, and can be mentioned as drugs to be added to the polymer.
Furthermore, an anticancer agent, an immunosuppressive agent, an antibiotic, an antithrombotic agent, an HMG-CoA reductase inhibitor, an AT1 receptor antagonist, an ACE inhibitor, a calcium antagonist, an anti-inflammatory agent having a decomposition temperature of 100 ° C. or higher Antiallergic agents, antioxidants and the like can be mentioned as drugs to be added to the polymer. These agents suppress inflammation or cell proliferative responses induced by the polymer in living tissue in contact with the polymer and suppress restenosis.

The drug content is appropriately selected within the range of 100 ppm to 30% by weight in consideration of the type of drug, the therapeutic effect, and the like.
If the mixing amount of the drug is less than 100 ppm, it is difficult to expect a therapeutic effect, and if the drug content exceeds 30% by weight, the released amount of the drug becomes too large, and adversely affects the mechanical properties of the polymer molding. There is a risk of giving. Preferably, it is in the range of 1 to 20% by weight.

  The particle size of the drug particles is preferably less than 30 μm. If the particle size is larger than this, uniform mixing with the polymer becomes difficult, and it becomes difficult to maintain the uniformity of release in vivo. For this reason, it is preferable to pulverize before mixing with a polymer so that a chemical | medical agent may become below said particle diameter. Examples of the pulverization method include, but are not limited to, a mechanical pulverization method such as a ball mill, a vertical jet mill, a planetary ball mill, a vibration mill, a spray drying method, a freeze drying method, a recrystallization method, and the like. is not.

(Mixture of bioabsorbable polymer and drug)
Bioabsorbable polymer pellets are usually obtained in a cylindrical shape with a circle diameter of 1 to 6 mm and a length of 1 to 6 mm or a sphere with a length of 1 to 6 mm. The drug is pulverized and pulverized as necessary. Are mixed in a mixer and supplied to a molding machine such as an extruder.
Examples of the mixer used for mixing include, but are not limited to, a mixer such as a Banbury mixer and a super mixer. Alternatively, the polymer pellets and the drug may be supplied in a fixed amount to the extruder and mixed in the extruder. Or the dispersibility of the chemical | medical agent in a polymer may be further improved by mixing the pellet (masterbatch) once mixed with the polymer and the chemical | medical agent with a mixer, and extrusion-molding.

(Melt molding)
The mixture in which the bioabsorbable polymer and the drug are mixed can be supplied to a molding machine, heated and melted, and molded into a tube having a predetermined shape. The molding temperature is preferably selected at a temperature higher than the melting temperature of the bioabsorbable polymer and lower than the decomposition temperature of the drug.
As a melt molding method, a normal molding method such as extrusion molding or injection molding is used, which is molded into a tube shape. As the extruder, a single-screw or twin-screw extruder can be used. A polymer and drug mixture in a molten state is extruded from a die and melt-formed into a tube shape.
The outer diameter of the tube varies greatly depending on the application of the stent, but it is preferably in the range of 0.5 to 2.0 mm for a coronary stent. The thickness of the tube is preferably in the range of 0.05 to 0.3 mm.
The mixed state of the bioabsorbable polymer and the drug after melting is such that the bioabsorbable polymer has a sea structure, and the drug is preferably dispersed in an island shape in this sea structure. It is not preferable that the distribution or the aggregation of the drug occurs because the sustained release is hindered.

(Co-extrusion)
As described above, the stent according to the present invention is obtained by melt-molding a composition comprising a crystalline bioabsorbable polymer having a melting point of 90 ° C. or higher and a drug having a decomposition temperature of 100 ° C. or higher into a tube shape, The tubular molded body may have not only a single layer structure but also a multilayer structure in which the single layer is a main layer and auxiliary outer layers and / or inner layers are formed on the outer surface, the inner surface or both surfaces thereof. In this case, a multilayer structure can be obtained by coextrusion using a multilayer die as the die.
The auxiliary layer is composed of a bioabsorbable polymer and a drug. However, since the auxiliary layer is an auxiliary layer, the bioabsorbable polymer can only be a bioabsorbable polymer having a melting point of 90 ° C. or higher. Alternatively, a polymer having a melting point of 90 ° C. or lower, such as polycaprolactone, may be used. Moreover, as a chemical | medical agent, when a polymer whose melting | fusing point is 90 degrees C or less is used as a bioabsorbable polymer, not only the above-mentioned decomposition | disassembly temperature is 100 degreeC or more, but a decomposition temperature is lower than 100 degreeC. A drug may be used.
In the case of such a multilayer structure, the content of the drug may be included more on the outer surface or the inner surface than the main layer.

(coating)
In the stent according to the present invention, the inner layer, the outer surface or both surfaces of the main layer are coated with a solution in which a composition comprising a bioabsorbable polymer and a drug is dissolved by spraying or the like, so that the auxiliary inner layer and / or An outer layer may be formed. When an auxiliary layer is formed by coating, the bioabsorbable polymer used does not need to be a crystalline polymer having a melting point of 90 ° C. or higher, and includes a bioabsorbable polymer having a melting point of less than 90 ° C. It can select suitably from an absorptive polymer. In addition, as a drug, not only a drug having a decomposition temperature of 100 ° C. or higher, but also a drug can be selected and used regardless of the decomposition temperature.

(Pattern formation)
A stent can be manufactured by forming a mesh by cutting a tube surface obtained by melt molding according to a pattern by a laser cutting technique based on pattern information stored in a computer. In addition, about the shape of a pattern, as disclosed in Japanese Patent Nos. 3654627 and 3605388 related to metal stents, it is composed of a straight or relatively straight shape and a shape having a curve. can do. By having such a shape, it is possible to expand in the radial direction while minimizing the axial dimensional change required for the stent.

  Hereinafter, the present invention will be described in more detail based on examples and comparative examples, but the present invention is not limited to the examples.

<Example 1>
A chip of poly (DL-lactic acid) (D / L = 7/93) (melting point: 153 ° C., glass transition temperature: 64 ° C.) and argatroban (decomposition temperature: 180-220 ° C.) (weight average particle size: 2 μm; A mixture in which 2% by weight of a maximum particle size of 30 μm or less) was mixed with poly (DL-lactic acid) was supplied to an extruder and melted at 170 ° C., while outer diameter: 1.6 mm, wall thickness: 0 A 2 mm tube was molded. The obtained tube was subjected to laser processing to produce a stent having the shape shown in FIG.
Argatroban was adjusted by recrystallization and classification so that the weight average particle size was 2 μm and the maximum particle size was 30 μm or less before polymer mixing.
As for the mixed state of the bioabsorbable polymer and the drug, it was observed by microscopic observation (magnification factor 500 times) that the drug was uniformly dispersed in islands in the sea polymer.
The obtained stent was mounted on the balloon catheter surface, water was injected under pressure into the balloon, and the stent was expanded under an atmosphere of 36 ° C. until the outer diameter of the stent became 3.0 mm. In order to evaluate the shape retention, the balloon was then deflated and removed from the stent, and after 1 week, the outer diameter of the stent was measured to be 2.9 mm. The shape retention was good.

<Example 2>
Argatroban powder was dispersed in polydioxanone (melting point = 106 ° C., glass transition temperature <20 ° C.) and supplied to an extruder to form a tube. This tube was laser processed in the same manner as in Example 1 to produce a stent. When this stent was evaluated for shape retention in the same manner as in Example 1, the diameter of 3.0 mm at the time of expansion was 2.6 mm after one week.

<Comparative Example 1>
Amorphous poly (D, L-lactic acid) (D / L = 35/65) (melting point: none, glass transition temperature 47 ° C.) was mixed with argatroban in the same manner as in Example 1, and the mixture was added to the extruder. This was supplied, molded into a tube shape, and a stent was produced by laser processing.
The shape retention of the obtained stent was observed in the same manner as in Example 1. As a result, the outer diameter, which was 3.0 mm at the time of expansion, contracted to 2.3 mm after one week.

<Comparative example 2>
Argatroban powder was dispersed in polycaprolactone (melting point: 60 ° C, glass transition temperature: -60 ° C) and supplied to the extruder to make it into a tube shape, but the shape of the tube changed over time during molding. However, it was not possible to obtain an accurate tube capable of laser processing.

In the stent of the present invention, the drug is gradually released from the bioabsorbable polymer constituting the stent placed in the living body, and then the bioabsorbable polymer disappears in the living body. A stent that is non-harmful due to the presence of the polymer and is very effective in treatment is provided.
Therefore, the present invention is applied in the field of molding production for molding a bioabsorbable polymer tube used as a stent, the field of medical device production for producing a stent from the molding, the medical industry for treatment using this stent, etc. High availability on.

  As described above, the preferred embodiments of the present invention have been described with reference to the drawings, but various additions, modifications, or deletions can be made without departing from the spirit of the present invention. Included in the range.

Claims (14)

In a stent composed of a molded body obtained by melt-molding the bioabsorbable polymer (A) into a tube shape,
The bioabsorbable polymer (A) is a crystalline polymer having a melting point of 90 ° C. or higher, and a composition containing the bioabsorbable polymer (A) and a drug (X) having a decomposition temperature of 100 ° C. or higher is melted. A stent formed by molding.   The stent according to claim 1, wherein the bioabsorbable polymer (A) has a melting point of 110 ° C or higher and the decomposition temperature of the drug (X) is 120 ° C or higher.   The stent according to claim 1 or 2, wherein the bioabsorbable polymer (A) is a crystalline polymer having a glass transition temperature of 40 ° C or higher.   The bioabsorbable polymer (A) according to any one of claims 1 to 3, wherein the bioabsorbable polymer (A) is polylactic acid, and in the polylactic acid, a ratio of L-form to D-form (D / L ratio) is 10 in mass ratio. A stent in the range of / 90 to 0/100.   The stent according to any one of claims 1 to 4, wherein the drug (X) is argatroban.   The stent according to any one of claims 1 to 5, wherein the drug (X) is a particle having a particle size of 30 µm or less.   The stent according to any one of claims 1 to 6, wherein the molded body has a sea-island structure in which the bioabsorbable polymer (A) is the sea and the drug (B) is an island.   The stent according to any one of claims 1 to 7, wherein the drug (X) is contained in a range of 100 ppm to 30 parts by weight with respect to 100 parts by weight of the bioabsorbable polymer (A).   The stent according to any one of claims 1 to 8, wherein the tube has a multilayer structure in which a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube.   The stent according to claim 9, wherein the bioabsorbable polymer (B) and the bioabsorbable polymer (A) are the same or different from each other, and the drug (Y) and the drug (A) are the same. In the method of manufacturing a stent, the bioabsorbable polymer is melt-molded into a tube shape and processed so as to form a predetermined pattern in the obtained tube-shaped molded body.
Production of a stent characterized by mixing a bioabsorbable polymer (A), which is a crystalline polymer having a melting point of 90 ° C. or higher, with a drug (X) having a decomposition temperature of 100 ° C. or higher and melt-molding it into a tube shape. Method.   The method for producing a stent according to claim 11, wherein a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube by coextrusion.   12. The method for manufacturing a stent according to claim 11, wherein a layer containing the bioabsorbable polymer (B) and the drug (Y) is formed on one side or both sides of the tube by coating. 14. The manufacture of a stent according to claim 12 or 13, wherein the bioabsorbable polymer (B) and the bioabsorbable polymer (A) are the same or different from each other in the drug (Y) and the drug (X). Method.

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