Microsphere composition for contraceptive microneedle and contraceptive microneedle comprising same

Abstract

The invention provides a microsphere composition for a contraceptive microneedle and the contraceptive microneedle containing the composition. The microsphere composition for the contraceptive microneedle comprises one selected from the group consisting of sustained-release estrogen microspheres, sustained-release progesterone microspheres and mixtures thereof, and the sustained-release estrogen microspheres comprise 400-600 parts by weight of biodegradable polymer per 100 parts by weight of estrogen, every 100 parts by weight of progesterone and hydroxypropyl-beta-cyclodextrin (HP [beta] CD) in the sustained-release progesterone microspheres comprise 700-900 parts by weight of a biodegradable polymer, and the molar ratio of the progesterone to the hydroxypropyl-beta-cyclodextrin is (1: 2)-(1: 3). The microsphere composition for a contraceptive microneedle according to the present invention can stably encapsulate a drug, exhibits a sustained-release drug effect for at least one week, and has a particle size (Dv90) suitable for a microneedle. According to the contraceptive microneedle or the contraceptive microneedle patch, administration is convenient, the contraceptive microneedle or the contraceptive microneedle patch is used once a week, the transdermal medicine permeability is good, the short attachment time is allowed, and the medicine is slowly released for at least one week.

Description

Technical Field

[0001] The present invention relates to a microsphere composition for contraceptive micro needles and a contraceptive micro needle comprising the same, and more particularly to a microsphere composition for contraceptive micro needles comprising a sustained-release estrogen microsphere and / or a sustained-release progesterone microsphere as an active ingredient, and a contraceptive micro needle comprising the composition. Background Art

[0002] Contraceptives are mainly used to prevent unplanned pregnancies and are also widely used to treat dysmenorrhea, irregular menstruation, polycystic ovary syndrome, menorrhagia, and premenstrual syndrome.

[0003] Contraceptives use estrogen and / or progesterone components to artificially regulate hormone levels to inhibit ovulation. Depending on the presence and type of progesterone, contraceptives have evolved to the fourth generation, and the side effects of each generation are different. The first-generation contraceptives were high-dose pure estrogen preparations with serious side effects such as thrombosis and abnormal bleeding, leading to their discontinuation. The second-generation contraceptives mainly included levonorgestrel as the main progesterone component but had side effects such as acne and hirsutism. The third-generation contraceptives, including gestodene, desogestrel, and norgestimate as the main progesterone components, reduced the side effects of hirsutism and acne caused by the second-generation contraceptives, and there were products such as Melian TM 、Myvlar TM and Mercilon TM on the market.

[0004] These contraceptives are used as oral contraceptives, requiring users to take one pill at the same time every day for 21 consecutive days and then stop taking the pill for 7 days. Failure to follow this schedule may reduce the concentration of the active ingredient below the level required for effective contraception, which means that users must carefully plan and follow their dosing cycle (Korean Published Patent No. 10-2007-0087141).

[0005] As an alternative to inconvenient oral contraceptives, transdermal contraceptives are on the rise. Transdermal administration can avoid many adverse side effects, especially beneficial for drugs with a short biological half-life, thereby reducing the total daily dose and reducing the chance of overdose or underdose. In addition, the transdermal system provides the benefit of rapid termination of drug administration by removing the drug delivery system from the skin.

[0006] An example of a transdermal contraceptive is a polymer patch containing a viscous polymer matrix (Korean Registered Patent No. 10-0758757). However, due to the skin barrier, the inherent problem of the polymer patch is the low skin permeability of the active ingredient, resulting in insufficient drug delivery efficiency. To achieve the best effect of the contraceptive, the hormone as the active ingredient must be released in a sustained manner. However, for sustained release, the polymer patch must adhere to the skin for a long time every day, which causes skin irritation and discomfort, especially during activities such as bathing in summer.

[0007] Therefore, there is a need to develop a transdermal contraceptive drug delivery system that is convenient for administration, has good transdermal drug permeability, and sustained release of active ingredients. Summary of the Invention

[0008] Technical Problems to be Solved

[0009] As a result of continuous research to meet the needs of traditional technologies, the inventors have developed sustained-release estrogen microspheres and sustained-release progesterone microspheres for contraceptive microneedles. By using these microspheres as active ingredients, contraceptive microneedles have been successfully manufactured, which are convenient for administration, have good transdermal drug permeability, and sustained drug release, thus completing the present invention.

[0010] Therefore, an object of the present invention is to provide a microsphere composition for contraceptive microneedles that is convenient for administration, has good transdermal drug permeability, and sustained release of active ingredients.

[0011] Another object of the present invention is to provide a contraceptive microneedle containing the microsphere composition, which is convenient for administration, has good transdermal drug permeability, and sustained release of active ingredients.

[0012] Another object of the present invention is to provide a contraceptive microneedle patch containing the microneedles.

[0013] Technical Solution

[0014] To achieve the above object, the present invention provides a microsphere composition for contraceptive microneedles that is convenient for administration, has good transdermal drug permeability, and sustained release of active ingredients.

[0015] In the present invention, the drug refers to estrogen and progesterone.

[0016] The microsphere composition for contraceptive microneedles includes one selected from the group consisting of sustained-release estrogen microspheres, sustained-release progesterone microspheres, and mixtures thereof as an active ingredient.

[0017] In the present invention, "sustained release" means that the drug encapsulated in the microspheres is released in a controlled manner, preferably releasing 70-80% by weight of the drug continuously within 120 hours.

[0018] In the present invention, the sustained-release estrogen microspheres and sustained-release progesterone microspheres are characterized in that the estrogen and progesterone encapsulated in the microspheres are released in vivo for at least one week, preferably up to one week. These sustained-release estrogen microspheres and sustained-release progesterone microspheres are further characterized in that within 120 hours after entering the application environment (for example, after administration to the human body), 70-80% by weight of the estrogen and progesterone encapsulated therein is continuously released.

[0019] In the present invention, estrogen refers to ethinyl estradiol (EE).

[0020] In the present invention, progesterone refers to one selected from the group consisting of desogestrel (DSG), gestodene, dienogest, levonorgestrel, norgestimate, norethisterone, drospirenone, trimegestone, and dydrogesterone.

[0021] In the present invention, per 100 parts by weight of estrogen in the sustained-release estrogen microspheres, 400 to 600 parts by weight of a biodegradable polymer may be included. Preferably, per 100 parts by weight of estrogen in the sustained-release estrogen microspheres, 400 parts by weight of a biodegradable polymer is included. When the estrogen content contained in the microspheres is within the above range, sustained release for at least one week can be achieved.

[0022] In the present invention, the biodegradable polymer refers to a polymer that degrades in vivo without causing high cytotoxicity or an inflammatory response when administered in vivo.

[0023] In the present invention, the particle size (Dv90) of the sustained-release estrogen microspheres is 20 μm or less, preferably less than 15 μm. If the particle size exceeds this range, the microspheres will become too large to be contained in the microneedles.

[0024] In the present invention, the biodegradable polymer that can be used for the sustained-release estrogen microspheres is selected from the group consisting of poly(lactide-co-glycolide) (PLGA), polylactide (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) glucose, and mixtures thereof. Most preferably, it is poly(lactide-co-glycolide) (PLGA).

[0025] In the present invention, the sustained-release estrogen microspheres can be prepared by the following steps: preparing an O / W (oil-in-water) emulsion containing a biodegradable polymer, estrogen, and a solvent, and then aggregating the emulsion into microspheres using the single-solvent evaporation method. Specifically, an oil phase containing estrogen and a solvent is prepared and dispersed into an aqueous phase containing a surfactant to prepare an O / W emulsion.

[0026] The solvent is selected from the group consisting of dichloromethane (DCM), chloroform, acetonitrile, dimethyl sulfoxide, dimethylformamide, ethyl acetate, and mixtures thereof, and among them, dichloromethane (DCM) is the most preferred.

[0027] The surfactant is selected from the group consisting of polyvinyl alcohol (PVA), polysorbate 20, polysorbate 60, polysorbate 80, and mixtures thereof, and among them, polyvinyl alcohol (PVA) is the most preferred.

[0028] In the present invention, the stirring for preparing the O / W emulsion is preferably carried out at a speed of 1600 rpm or higher for at least 12 hours. If the stirring speed is lower than 1600 rpm, the particle size (Dv90) of the microspheres will become too large, making them unsuitable for inclusion in the microneedles.

[0029] The sustained-release estrogen microspheres according to the present invention exhibit a sustained-release effect of estrogen for at least one week and have an average particle size suitable for inclusion in microneedles ( Figure 1 , Figure 2 ).

[0030] In the present invention, 700 to 900 parts by weight of a biodegradable polymer can be included per 100 parts by weight of progesterone in the sustained-release progesterone microspheres. Most preferably, 700 parts by weight of a biodegradable polymer can be included per 100 parts by weight of progesterone in the sustained-release progesterone microspheres.

[0031] The sustained-release progesterone microspheres according to the present invention may further include hydroxypropyl-β-cyclodextrin (HPβCD) for stabilizing progesterone. In the sustained-release progesterone microspheres, hydroxypropyl-β-cyclodextrin can be included at a molar ratio of progesterone to hydroxypropyl-β-cyclodextrin of 1:2 to 1:3.

[0032] When the contents of progesterone and hydroxypropyl-β-cyclodextrin in the sustained-release progesterone microspheres are within the above ranges, a sustained release of progesterone for at least one week is possible.

[0033] The particle size (Dv90) of the sustained-release progesterone microspheres according to the present invention is 20 μm or less, preferably 18 μm or less. If the particle size exceeds this range, the microspheres will be unsuitable for inclusion in the microneedles.

[0034] In the present invention, the biodegradable polymers that can be used for the sustained-release progesterone microspheres are selected from the group consisting of poly(lactide-co-glycolide) (PLGA) with a glycolic acid:lactic acid ratio of 1:2 - 4, poly(lactide-co-glycolide) glucose, and mixtures thereof. Poly(lactide-co-glycolide) (PLGA) with a glycolic acid:lactic acid ratio of 1:3 is most preferred.

[0035] The sustained-release progesterone microspheres according to the present invention can be prepared by the W / O / W (water / oil / water) double solvent evaporation method. Specifically, an aqueous phase containing hydroxypropyl-β-cyclodextrin dissolved in water is mixed with an oil phase containing a biodegradable polymer, progesterone, and a solvent. Then, the mixture is dispersed into an aqueous phase containing a surfactant to produce a W / O / W emulsion and aggregated into microspheres.

[0036] The solvent is selected from the group consisting of dichloromethane (DCM), chloroform, acetonitrile, dimethyl sulfoxide, dimethylformamide, ethyl acetate, and mixtures thereof, and among them, dichloromethane (DCM) is most preferred.

[0037] During the dispersion process, it is preferable to stir at a speed of 1600 rpm or higher for at least 12 hours. If the stirring speed is lower than 1600 rpm, the average particle size of the microspheres will become too large to be included in the microneedles.

[0038] The surfactant can be selected from the group consisting of polyvinyl alcohol (PVA), polysorbate 20, polysorbate 60, polysorbate 80, and mixtures thereof, wherein polyvinyl alcohol (PVA) is most preferred.

[0039] The sustained-release progesterone microspheres according to the present invention have a particle size (Dv90) suitable for microneedle encapsulation, and the surface of the microspheres has pores, enabling the sustained release of progesterone for at least one week ( Figure 7 、 Figure 8 ).

[0040] Another object of the present invention is to provide a contraceptive microneedle containing the above microsphere composition.

[0041] The contraceptive microneedle of the present invention can be prepared by mixing the above microsphere composition with a soluble material, a stabilizer, and a solvent to form a solution, and then loading the solution into a mold to form microneedles.

[0042] In the present invention, the soluble material is biodegradable in vivo and forms the structure of the microneedle. Therefore, the microneedle of the present invention can dissolve in body fluids after being inserted into the skin. The soluble material can be selected from the group consisting of hyaluronic acid (HA) or its salts, alginic acid (AA) or its salts, chitosan, collagen, gelatin, chondroitin, dextran, fibrin, agarose, amylopectin, cellulose, polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), polyvinyl alcohol (PVA), vinylpyrrolidone-vinyl acetate copolymer, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, sodium carboxymethyl cellulose (CMC), and mixtures thereof, wherein hyaluronic acid or its salts are most preferred.

[0043] During the preparation of the microneedles according to the present invention, the soluble material can account for 20 - 30% by weight of the total solution (100% by weight).

[0044] The stabilizer is used to enhance the stability during the microneedle preparation process and can be one or more selected from the group consisting of xylitol, trehalose, lactose, sucrose, polyols, cyclodextrin, dextrin, starch, glucose, maltose, lactulose, turanose, melibiose, melezitose, sorbitol, and mannitol.

[0045] During the preparation of the microneedles according to the present invention, the content of the stabilizer can be 3 - 10% by weight of the total solution.

[0046] When preparing the microneedles according to the present invention, the content of the microsphere composition of the present invention can be 1-10% by weight of the total solution.

[0047] In the present invention, the solvent is water, preferably deionized water (D.W) or potassium phosphate buffer (PPB).

[0048] In the present invention, if necessary, a pH regulator such as NaOH can also be added during the preparation of the microneedles. The pH regulator can be any pH regulator commonly used in the preparation of microneedles.

[0049] In the present invention, if necessary, a plasticizer, a surfactant, a preservative, etc. can also be added during the preparation of the microneedles.

[0050] The microneedles of the present invention can include a needle portion protruding in one direction and a matrix layer supporting the needle portion. The needle portion has a shape suitable for skin penetration. The shape of the needle portion of the microneedles of the present invention can be conical, pyramidal, spherical, frustum-shaped, wedge-shaped, blade-shaped, etc., and generally should be a shape capable of penetrating the skin. The length of the needle portion is 500-1000 μm, preferably 750 μm. The thickness of the matrix layer is 0.1-1 mm, preferably 0.1-0.3 mm.

[0051] The needle portion of the microneedles of the present invention can be made separable from the matrix layer when inserted into the skin as needed. The microneedles of the present invention can also have a matrix layer made of different materials as needed. Therefore, the microspheres of the microneedles of the present invention can be uniformly distributed in the needle portion and the matrix layer, or only in the needle portion.

[0052] The microneedles of the present invention are soluble microneedles, which release sustained-release estrogen microspheres and / or sustained-release progesterone microspheres when biodegradable in vivo.

[0053] The microneedles of the present invention can include only sustained-release estrogen microspheres, only sustained-release progesterone microspheres, or sustained-release estrogen microspheres and sustained-release progesterone microspheres.

[0054] The microneedles of the present invention are convenient for administration, administered once a week, have excellent transdermal drug permeability by forming small holes in the skin, and the drug can be continuously released for at least one week by using the sustained-release microspheres of the present invention.

[0055] Another object of the present invention is to provide a contraceptive microneedle patch containing the microneedles.

[0056] The contraceptive microneedle patch of the present invention has an adhesive layer laminated on one side of the matrix layer, allowing the microneedle patch to be attached to the skin for use. The microneedle patch can also include a protective film on the adhesive layer.

[0057] The contraceptive microneedle patch of the present invention provides continuous drug release for at least one week and has a short attachment time of less than 3 hours, making it usable as a female contraceptive.

[0058] Beneficial effects

[0059] The microsphere composition for contraceptive microneedles of the present invention can stably encapsulate drugs, and the drugs are continuously released for at least one week, and have a particle size (Dv90) suitable for microneedle encapsulation.

[0060] The contraceptive microneedles of the present invention are convenient for administration, administered once a week, have good transdermal drug permeability, continuously release drugs for at least one week, and have a short attachment time.

[0061] The contraceptive microneedle patch of the present invention continuously releases drugs for at least one week, has a short attachment time, and can be used as a female contraceptive. Description of the drawings

[0062] Figure 1 It is a scanning electron microscope (SEM) image of the ethinyl estradiol microspheres prepared in Preparation Example 1.

[0063] Figure 2 It is a graph showing the dissolution test results of the ethinyl estradiol microspheres prepared in Preparation Example 1.

[0064] Figure 3 It is an SEM image of the desogestrel microspheres prepared in Preparation Example 2.

[0065] Figure 4 It is a graph showing the dissolution test results of the desogestrel microspheres prepared in Preparation Example 2.

[0066] Figure 5 It is a graph showing the results of the stability analysis of desogestrel with different stabilizers.

[0067] Figure 6 It is a graph showing the results of the stability analysis of desogestrel with different molar ratios of desogestrel to stabilizer in the microspheres.

[0068] Figure 7 It is an SEM image of the desogestrel microspheres prepared in Preparation Example 4.

[0069] Figure 8 It is a graph showing the dissolution test results of the desogestrel microspheres prepared in Preparation Example 4.

[0070] Figure 9 It is an SEM image of the ethinyl estradiol microspheres of Example 2 and the desogestrel microspheres of Example 3.

[0071] Figure 10 It is an image of the microneedles and the needle parts of Examples 4 - 6. Detailed implementation manners

[0072] The present invention will be described in more detail in connection with specific embodiments to assist in understanding the present invention. However, these embodiments are only for better understanding the embodiments of the present invention and are not intended to limit the scope of the present invention.

[0073] Preparation Example 1: Sustained-release microspheres of ethinyl estradiol

[0074] <Microsphere preparation>

[0075] Ethinyl estradiol (EE) and PLGA 503H (Evonik GmbH, Germany) were added to 10 ml of dichloromethane (DCM) in the amounts shown in Table 1, mixed, and dissolved by sonication for 30 minutes to prepare an oil phase. The oil phase was dropped into 100 ml of a polyvinyl alcohol solution (5% PVA dissolved in deionized water), stirred at the stirring speed shown in Table 1, and dropped at a rate of 2 ml / min using a syringe pump to evaporate the DCM for 12 hours to form microspheres. The formed microspheres were precipitated by a centrifuge (2000 rpm, 10 minutes). The precipitated microspheres were filtered through a PVDF membrane filter with a pore size of 0.2 μm, washed twice with deionized water, and dried at room temperature for 12 hours to obtain the microspheres.

[0076] Table 1

[0077]

[0078] <Yield, drug loading, and encapsulation efficiency of the microspheres>

[0079] The drug encapsulated in the prepared microspheres was analyzed using an HPLC device (Agilent 1200 HPLC system), and the yield, drug loading, and encapsulation efficiency of the microspheres were calculated using the following formulas, as shown in Table 2:

[0080] Yield: Actual yield / Theoretical yield × 100 (%)

[0081] Drug loading: Amount of drug loaded / Weight of microspheres × 100 (%)

[0082] Encapsulation efficiency: Actual amount of drug loaded / Theoretical amount of drug loaded × 100 (%)

[0083] Table 2

[0084]

[0085] Comparative Example 4 shows that a low encapsulation efficiency (about 10.13%) is not suitable. It was confirmed that a higher content of ethinyl estradiol (EE) would reduce the encapsulation efficiency.

[0086] <Particle shape and size of the microspheres>

[0087] The particle shape of the microspheres was observed using an SEM device (Ultra Plus Carl Zeiss), and the results are asFigure 1 As shown, all the microspheres are spherical in shape.

[0088] In addition, the particle sizes (Dv10, Dv50, Dv90) of the microspheres were measured using a Mastersizer 3000E device (wet measurement), and the results are shown in Table 3.

[0089] Table 3

[0090] Dv10 (μm) Dv50 (μm) Dv90 (μm) Distribution width (Span) Comparative Example 1 ME-1 8.17±0.01 16.9±0.28 36.57±2.62 1.67±0.12 Comparative Example 2 ME-3 3.48±0.01 6.45±0.06 9.95±0.10 1.00±0.01 Comparative Example 3 ME-4 1.50±0.01 4.88±0.02 9.77±0.11 1.69±0.01 Example 1 ME-5 1.98±0.01 6.25±0.05 12.07±0.31 1.60±0.03 Example 2 ME-6 1.61±0.01 4.88±0.07 10.50±0.46 1.82±0.06 Comparative Example 4 ME-7 1.55±0.01 5.36±0.02 11.97±0.59 1.94±0.10

[0091] The particle size (Dv90) shown in Comparative Example 1 was 36.57 ± 2.62 μm, which is not suitable for use in microneedles. It has been confirmed that stirring at a speed of 1600 rpm or higher during the preparation of the microspheres can make the particle size (Dv90) approximately 10 μm, which is suitable for incorporation into microneedles.

[0092] <Dissolution Test - Sustained Release Test>

[0093] The sustained release characteristics were analyzed by performing a dissolution test on the microspheres prepared above.

[0094] In a shaking bath (at 37°C, 50 rpm), 40 ml of dissolution solution (PBS pH 7.4 containing 0.5% Tween 80) was added to a 50 ml conical tube. The microspheres were weighed to contain 1000. Ethinyl estradiol (EE) was weighed and added to the dissolution solution for dissolution evaluation.

[0095] Before sampling, the microspheres were precipitated using a centrifuge (1500 rpm, 5 min), and 10 ml of the supernatant was taken for HPLC analysis. 10 ml of the dissolution solution was replenished, and the sampling times were set at 4, 8, 16, 24, 48, 72, 96, and 120 h respectively.

[0096] According to the following equations, the dissolution time and dissolution rate results (dissolution rate less than 60%) were used to calculate the kinetics:

[0097] Zero order: Q t = Q0 + K0 × t

[0098] First order:

[0099] Hixcon - Crowell dissolution equation: W0 1 / 3 - W t 1 / 3 = K Hc × t

[0100] Higuchi diffusion equation: Q = K H × t 1 / 2

[0101] Krosmeyer - peppas fitting equation:

[0102] The test results are as Figure 2 shown in Table 4 and Table 5.

[0103] Table 4

[0104]

[0105] Table 5

[0106]

[0107]

[0108] As shown in Table 4 and Figure 2 as shown, the lower the PLGA ratio, the faster the dissolution rate. The microspheres of Example 1 and Example 2 showed a drug release of about 77.7% to 81% at 120 hours, making them suitable for one-week sustained release.

[0109] As shown in Table 5, the dissolution pattern showed a sustained release pattern and conformed to Higuchi or Korsmeyer-Peppas kinetics.

[0110] Based on these analysis results, the optimal preparation method of the sustained-release estrogen microspheres of the present invention is to mix 400 to 600 parts by weight of a biodegradable polymer with 100 parts by weight of estrogen and stir at a speed of 1600 rpm or higher for at least 12 hours.

[0111] Preparation Example 2: Determination of the preparation conditions of desogestrel microspheres

[0112] <Microsphere preparation>

[0113] Add desogestrel (DSG) and PLGA 503H (Evonik GmbH, Germany) in the amounts shown in Table 6 to 10 ml of dichloromethane (DCM), mix, and dissolve by ultrasonic treatment for 30 minutes to prepare an oil phase. Drop the oil phase into 100 ml of a polyvinyl alcohol solution (5% PVA dissolved in deionized water), stir at the stirring speed shown in Table 6, stir with an injection pump at a speed of 2 ml / min to evaporate DCM, and stir for 12 hours to form microspheres. Precipitate the formed microspheres with a centrifuge (2000 rpm, 10 minutes). Filter the precipitated microspheres through a 0.2 PVDF membrane filter, wash twice with deionized water, and dry at room temperature for 12 hours to obtain microspheres.

[0114] Table 6

[0115]

[0116] <Yield, drug loading and encapsulation efficiency of microspheres>

[0117] The drug encapsulated in the prepared microspheres was analyzed using an HPLC device (Agilent 1200 HPLC system), and the yield, drug loading, and encapsulation efficiency of the microspheres were calculated using the above formula in Preparation Example 1. The results are shown in Table 7.

[0118] Table 7

[0119]

[0120] <Particle shape and size of microspheres>

[0121] The particle shape of the microspheres was observed using an SEM device (Ultra Plus Carl Zeiss), and the results are as Figure 3 shown. All the microspheres were spherical.

[0122] In addition, the particle size (Dv10, Dv50, Dv90) of the microspheres was measured using a Mastersizer 3000E device (wet measurement), and the results are shown in Table 8.

[0123] Table 8

[0124] Dv10 (μm) Dv50 (μm) Dv90 (μm) Distribution width (Span) Comparative Example 4 MD-3 14.00±0.10 27.90±0.08 55.00±1.42 1.47±0.04 Comparative Example 5 MD-4 10.03±0.06 20.37±0.21 40.40±1.49 1.49±0.06 Comparative Example 6 MD-5 3.71±0.00 8.20±0.03 12.60±0.01 1.08±0.01

[0125] The particle sizes (Dv90) shown in Comparative Example 4 and Comparative Example 5 were approximately 55 μm, which were not suitable for microneedles. It was confirmed that a large amount of biodegradable polymer would excessively increase the microsphere size. In addition, it was confirmed that stirring at a speed of 1600 rpm or higher during the preparation of the microspheres could make Dv90 approximately 10 μm, which is the desired size for incorporation into microneedles.

[0126] <Dissolution test - Sustained release test>

[0127] According to the same method as in Example 1, the dissolution test was carried out on the microspheres prepared as described above to analyze the sustained release characteristics. The test results are as Figure 4 and Table 9 shown.

[0128] Table 9

[0129]

[0130] As shown in Table 9 and Figure 4 shown, the microspheres of Comparative Example 4 to Comparative Example 6 showed a drug release amount lower than approximately 44% at 120 hours, which was not suitable for one-week sustained release, and the stability of the drug (DSG) needed to be improved.

[0131] Preparation Example 3: Preparation of desogestrel microspheres with different stabilizers

[0132] <Selection of stabilizer>

[0133] To select a suitable stabilizer for preparing desogestrel microspheres with enhanced stability, compositions containing stabilizers as shown in Table 10 were prepared, and films were prepared using these compositions for stability testing.

[0134] Table 10

[0135] Content (mg) Composition 1 Composition 2 Composition 3 Composition 4 DSG 5 5 5 5 PLGA 50 50 50 50 Hydroxypropyl-β-cyclodextrin (HPβCD) 58 - - Tocopherol - - 36 - BHA (Butylated hydroxyanisole) - - - 36

[0136] Specifically, an ethanol solution dissolving the drug (DSG) and each stabilizer was mixed with a DCM solution containing PLGA. After mixing, the mixture was dried using a nitrogen evaporator to form a film with a thickness of 50 - 100 μm.

[0137] Each film was subjected to stability analysis immediately after production, and also after being stored in a constant temperature and humidity chamber at 30 °C and 65% relative humidity (moderate accelerated conditions) for 8 weeks.

[0138] Specifically, for stability analysis, each film was completely dissolved in 5 ml of diluent (a 1:1 mixture of phosphate buffer solution at pH 3.5 and 78% acetonitrile). The resulting solution was shaken well, and then DSG was quantitatively analyzed by HPLC under the conditions described in Table 11 below. The results are shown in Table 12 and Figure 5 in.

[0139] Table 11

[0140]

[0141] Table 12

[0142] Content (%) Composition 1 Composition 2 Composition 3 Composition 4 Initial 91.45±4.95 102.04±1.38 93.82±4.97 97.32±3.39 After 2 weeks 47.33±5.13 85.96±3.30 57.42±6.60 62.77±1.78 After 4 weeks 23.59±1.64 85.64±1.80 43.27±1.33 53.64±4.23 After 8 weeks 6.90±1.08 72.70±13.6 11.76±3.18 33.08±0.55

[0143] As shown in Table 12 and Figure 5 it was confirmed that using hydroxypropyl - β - cyclodextrin (HPβCD) as a stabilizer could prevent the degradation of DSG and ensure stability after 8 weeks under moderate accelerated conditions.

[0144] <Preparation of Microspheres Containing Stabilizers and Composition Ratios>

[0145] Add HPβCD in the amount shown in Table 13 to 2 ml of deionized water, mix and sonicate for 30 minutes to dissolve, obtaining an aqueous phase. Add desogestrel (DSG) and PLGA 503H (Evonik GmbH, Germany) to 10 ml of dichloromethane (DCM), mix and sonicate for 30 minutes to dissolve, obtaining an oil phase. Mix the aqueous phase and the oil phase, homogenize at 12,000 rpm for 10 seconds to obtain a mixed solution. Stir 100 ml of a polyvinyl alcohol solution (5% PVA dissolved in deionized water) at 1,600 rpm, and add the mixed solution dropwise to the polyvinyl alcohol solution at a rate of 2 ml / min using a syringe pump. Continue stirring for 12 hours to evaporate DCM, thereby forming microspheres. Precipitate the microspheres using a centrifuge (2,000 rpm, 10 minutes). Filter the precipitated microspheres using a 0.2 PVDF membrane filter, wash twice with deionized water, and then dry at room temperature for 12 hours to complete the preparation of the microspheres.

[0146] Table 13

[0147]

[0148] For the prepared microspheres, stability analysis was carried out immediately after production, and stability analysis was also carried out after storing in a constant temperature and humidity chamber at 40 °C and 75% relative humidity (accelerated conditions) for 8 weeks. The stability analysis involved quantifying DSG using the same HPLC method as described above. The results are shown in Table 14 and Figure 6 .

[0149] Table 14

[0150]

[0151] As shown in Table 14 and Figure 6 , the microspheres prepared by adding hydroxypropyl-β-cyclodextrin (HPβCD) as a stabilizer to desogestrel (DSG) in a molar ratio of 1:2 to 1:3 showed maintenance of stability, and even after storing for 8 weeks under accelerated conditions, DSG did not degrade.

[0152] Preparation Example 4: Preparation of Sustained-Release Desogestrel Microspheres

[0153] <Microsphere Preparation>

[0154] 705 mg of HPβCD was added to 2 ml of deionized water, mixed and sonicated for 30 minutes to dissolve, and an aqueous phase was prepared. DSG and PLGA 503H (lactic acid:glycolic acid 50:50), 753H (75:25), 203H (100:0), 503 (50:50) (Evonik Co., Ltd., Germany) were respectively added to 10 ml of dichloromethane (DCM) in the amounts shown in Table 15, sonicated for 30 minutes to mix and dissolve, and an oil phase was prepared. The aqueous phase and the oil phase were mixed and homogenized at 12,000 rpm for 10 seconds to prepare a mixed solution. While stirring 100 ml of a polyvinyl alcohol solution (5% PVA dissolved in deionized water) at 1600 rpm, the mixed solution was added dropwise to the polyvinyl alcohol solution at a rate of 2 ml / min using a syringe pump. Stirring was continued for 12 hours to evaporate DCM, thereby forming microspheres. Then the microspheres were precipitated using a centrifuge (2000 rpm, 10 minutes). The precipitated microspheres were filtered using a 0.2 PVDF membrane filter, washed twice with deionized water, and dried at room temperature for 12 hours to complete the preparation of the microspheres.

[0155] Table 15

[0156]

[0157] <Yield, drug loading and encapsulation efficiency of microspheres>

[0158] The drug encapsulated in the prepared microspheres was analyzed using an HPLC device (Agilent 1200 HPLC system), and the yield, drug loading and encapsulation efficiency of the microspheres were calculated using the above formula in Preparation Example 1, as shown in Table 16.

[0159] Table 16

[0160]

[0161] For different grades of PLGA, their yields were similar, and the drug loading of PLGA formulations (MD-18 or MD-19) with a higher lactic acid / glycolic acid ratio increased by 1 - 1.5%.

[0162] <Particle shape and size of microspheres>

[0163] The particle shape of the microspheres was observed using an SEM device (Ultra Plus Carl Zeiss), and the results are as Figure 7 shown. Pores were observed on the surfaces of MD-18 and MD-19 microspheres. This may be due to the increased hydrophobicity of the outer phase, resulting in faster diffusion of the hydrophilic solvent in the inner phase.

[0164] In addition, the particle sizes (Dv10, Dv50, Dv90) of the microspheres were measured using a Mastersizer 3000E device (wet measurement), and the results are shown in Table 17.

[0165] Table 17

[0166] Dv10 (μm) Dv50 (μm) Dv90 (μm) Distribution width (Span) Comparative Example 7 MD-6 2.53±0.01 7.98±0.03 23.47±1.08 2.62±0.12 Example 3 MD-18 4.056±0.02 8.13±0.03 18.63±0.49 1.79±0.05 Comparative Example 8 MD-19 3.76±0.00 7.12±0.01 12.90±0.20 1.28±0.02 Comparative Example 9 MD-20 3.546±0.01 7.05±0.00 18.07±0.06 2.05±0.00

[0167] For the microspheres of Comparative Example 7, the particle size (Dv90) was approximately 23 μm, which was too large for micronization (incorporation).

[0168] <Dissolution Test - Sustained Release Test>

[0169] According to the same method as in Example 1, the dissolution test was carried out on the above - prepared microspheres to analyze the sustained - release characteristics. The test results are as Figure 8 and Table 18 show.

[0170] Table 18

[0171]

[0172] As shown in Table 18 and Figure 8 shown, the microspheres of Example 3 showed approximately 75% drug release at 120 hours, indicating suitability for one - week sustained release.

[0173] Due to the influence of the pores on the surface of the microspheres, the microspheres of Example 3 (MD - 18) showed a rapid - release curve after 4 hours, while the microspheres of Comparative Example 8 (MD - 19) showed a delayed elution curve despite the presence of pores due to the increased ratio of lactic acid / glycolic acid (increased hydrophobicity).

[0174] Based on the above analysis, the sustained - release progesterone microspheres of the present invention preferably contain 700 to 900 parts by weight of a biodegradable polymer per 100 parts by weight of progesterone. In addition, hydroxypropyl - β - cyclodextrin is preferably included in the microspheres, and the molar ratio of progesterone to hydroxypropyl - β - cyclodextrin is 1:2 to 1:3. The ratio of glycolic acid:lactic acid of the biodegradable polymer is preferably 1:2 to 4, the stirring speed during the preparation of the microspheres is at least 1600 rpm, and the stirring time is at least 12 hours.

[0175] Preparation Example 5: Preparation of contraceptive microneedles

[0176] <Preparation of Solution for Micro - needle Preparation>

[0177] The solution for micro - needle preparation was prepared using the ethinylestradiol microspheres of Example 2 and the desogestrel microspheres of Example 3 ( Figure 9 ), and the formulation is shown in Table 19:

[0178] Table 19

[0179] Content (weight percentage) Example 4 Example 5 Example 6 Ethinylestradiol microspheres (Example 2, ME-6) -. 1.43 1.43 Desogestrel microspheres (Example 3, MD-18) 5.07 -. 5.07 HA 25.50 26.48 25.12 Xylitol 5.67 5.88 5.58 Deionized water 63.76 66.21 62.80 Total amount 100.00 100.00 100.00

[0180] Specifically, microspheres (MD-18 119.23 mg in Example 4, ME-6 32.40 mg in Example 5, MD-18 121.13 mg and ME-6 34.17 mg in Example 6) were added to a reactor, and then 1500 mg of purified water was added. The mixture in the reactor was vortexed for 3 minutes and ultrasonically treated for 2 minutes to ensure that there were no agglomerated (aggregated) microspheres. 133.33 mg of xylitol was added to the reactor and vortexed for 3 minutes and ultrasonically treated for 2 minutes until completely dissolved. 600 mg of hyaluronic acid (HA; sodium hyaluronate) was added to the reactor, vortexed for 5 minutes, and ultrasonically treated for 2 minutes until completely dissolved, and then degassed under reduced pressure to obtain a solution for micro-needle preparation.

[0181] <Micro-needle preparation>

[0182] 0.2 g of the solution prepared above was loaded into a PMDS negative mold in the shape of a circular patch. After loading, the mold was placed in a dryer and the pressure was reduced to ensure that the solution filled the negative mold. After removing the bubbles with compressed air, it was dried at room temperature for 16 hours. Then the prepared micro-needles were separated from the mold. Photographs of the prepared micro-needles and the needle parts are as Figure 10 shown.

[0183] If necessary, the micro-needles can be attached with tape or the like on the back to enhance the usability in the form of a patch.

[0184] As shown in Figure 10, it was confirmed that the micro-needles of Examples 4 to 6 were well formed and the microspheres were coated inside their needle parts.

[0185] Experimental Example 1: Analysis of microneedle strength and drug content

[0186] <Micro-needle strength>

[0187] For each of the micro-needles of Examples 4 to 6 prepared in Example 5, the compressive strength was measured using a universal material testing machine (Instron34sc-05) at a test speed of 0.1 mm / s and a test end condition of 100 N. For data analysis, for each of the prepared micro-needles, the force value corresponding to the compression displacement was taken at 1 / 3 of the full length of the needle part, and the force value of 1 micro-needle was calculated using the measured force value / number of needles formula. The results are shown in Table 20.

[0188] Table 20

[0189] Index Example 4 Example 5 Example 6 Needle pressing strength (N / number of needles) 0.14 0.12 0.21

[0190] As shown in Table 20, the micro-needles of Examples 4 - 6 had sufficient strength to penetrate the skin.

[0191] <Analysis of micro-needle drug content>

[0192] For each of the microneedles prepared in Preparation Examples 4 to 6 prepared in Preparation Example 5, the drug content was analyzed using HPLC (Agilient 1260 Infinity II Prime LC). As a sample, each microneedle was dissolved in 1 ml of a 50% ACN aqueous solution. Analysis was carried out under the conditions shown in Table 21 (desogestrel) and Table 22 (ethinylestradiol) below, and the results are shown in Table 23.

[0193] Table 21

[0194] Chromatographic column YMC-Pack ODS-AQ / 250*4.6mm / 5um Mobile phase acn:dw = 73:27 Flow rate 1.0 mL / min Detector DAD (205μm) Running time 35 min Chromatographic column temperature 50 Injection volume 15 μL Sample solution 50% acetonitrile aqueous solution

[0195] Table 22

[0196] Chromatographic column Shiseido CAPCELL PAK C18 MG / 150*4.6mm / 5um Mobile phase acn:dw = 1:1 Flow rate 1.0 mL / min Detector DAD (280μm) Running time 15 min Chromatographic column temperature 25 Injection volume 25 μL Sample solution 50% acetonitrile aqueous solution

[0197] Table 23

[0198] Example 4 Example 5 Example 6 Desogestrel content (mg) 0.513 -. 0.697 Ethinylestradiol content (mg) -. 0.070 0.053

[0199] As shown in Table 23, it was confirmed that the microspheres had been sufficiently incorporated into the microneedles.

Claims

1. A microsphere composition for contraceptive microneedle, comprising: One selected from the group consisting of sustained-release estrogen microspheres, sustained-release progesterone microspheres and mixtures thereof, wherein the sustained-release estrogen microspheres contain 400 to 600 parts by weight of a biodegradable polymer per 100 parts by weight of estrogen, wherein the biodegradable polymer is any one selected from the group consisting of poly(lactide-co-glycolide) (PLGA), polylactide (PLA), polyglycolide (PGA), poly(lactide-co-glycolide) glucose and mixtures thereof, wherein stirring is performed at a speed of 1600 rpm or more for at least 12 hours during the preparation of the microspheres, wherein the particle size (Dv90) of the microspheres is 20 μm or less, and 70-80% by weight of the estrogen in the microspheres is continuously released within 120 hours; The sustained-release progesterone microspheres contain 700 to 900 parts by weight of a biodegradable polymer per 100 parts by weight of progesterone and hydroxypropyl-β-cyclodextrin (HPβCD), the molar ratio of progesterone to hydroxypropyl-β-cyclodextrin is 1:2 to 1:3, wherein the biodegradable polymer is any one selected from the group consisting of poly(lactide-co-glycolide) (PLGA) having a glycolic acid:lactic acid ratio of 1:2 to 4, poly(lactide-co-glycolide) glucose and a mixture thereof, wherein the particle size (Dv90) of the microspheres is 20 μm or less, and 70-80% by weight of the estrogen in the microspheres is continuously released within 120 hours.

2. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The estrogen is ethinyl estradiol, and the progesterone is any one selected from the group consisting of desogestrel, gestodene, dienogest, levonorgestrel, norgestimate, norethisterone, drospirenone, trimegestone, and dydrogesterone.

3. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The sustained-release estrogen microspheres contain 400 parts by weight of a biodegradable polymer per 100 parts by weight of estrogen, wherein the biodegradable polymer is poly(lactide-co-glycolide) (PLGA).

4. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The sustained-release progesterone microspheres contain 700 parts by weight of a biodegradable polymer per 100 parts by weight of progesterone and hydroxypropyl-β-cyclodextrin (HPβCD), and the molar ratio of progesterone to hydroxypropyl-β-cyclodextrin is 1:

2.

5. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The biodegradable polymer of the sustained-release progesterone microspheres is poly(lactide-co-glycolide) (PLGA) with a glycolic acid:lactic acid ratio of 1:

3.

6. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The surfaces of the sustained-release progesterone microspheres are formed with pores.

7. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The composition comprises only sustained-release estrogen microspheres.

8. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The composition comprises only sustained-release progesterone microspheres.

9. The microsphere composition for contraceptive microneedle according to claim 1, wherein: The composition comprises sustained-release estrogen microspheres and sustained-release progesterone microspheres.

10. A contraceptive microneedle prepared from the composition according to any one of claims 1 to 9, wherein The microneedle includes a needle portion protruding in one direction and a matrix layer supporting the needle portion.

11. The contraceptive microneedle according to claim 10, wherein: The needle portion can be separated from the matrix layer when inserted into the skin.

12. The contraceptive microneedle according to claim 10, wherein: The microneedles are prepared using a mold.

13. A contraceptive microneedle patch comprising the microneedle according to claim 10.

14. The contraceptive microneedle patch according to claim 13, wherein: The contraceptive microneedle patch is used once a week.

Images