JP6339364B2 - Amorphous brimonidine tartrate and method for producing the same - Google Patents

Description

  The present invention relates to amorphous brimonidine tartrate and a method for producing the same.

  Brimonidine [chemical name: 5-bromo-N- (4,5-dihydro-1H-imidazol-2-yl) quinoxalin-6-amine] is known to be useful as a cardiovascular regulator. . For example, in Japanese Patent Laid-Open No. 56-25176 (Patent Document 1), a benzene solution of 5-bromo-6-isothiocyanatoquinoxaline is added to a benzene solution of ethylenediamine and stirred to separate a lower oily substance. Washed, dissolved in methanol, refluxed until the release of hydrogen sulfide ceased, concentrated, and the resulting precipitate was collected by filtration and recrystallized from methanol to synthesize brimonidine with a melting point of 250-251 ° C. An example is given. This document describes that the obtained brimonidine is useful as an antihypertensive agent.

  As pharmaceutical use of brimonidine, uses other than the above-mentioned medicine are also known. For example, Japanese Patent No. 2999240 (Patent Document 2) describes a method for reducing or maintaining intraocular pressure by directly administering brimonidine to a mammalian eye, and is useful for the treatment of glaucoma. Have been described. In the example of this document, the reaction product was collected by filtration from the reaction solution of 5-bromo-6-isothiocyanatoquinoxaline and ethylenediamine as in the example of Patent Document 1, and then dried under reduced pressure, with a melting point of 242 to 244. A crude product at 0 ° C. is prepared, the crude product is purified by an acid-base extraction method, a purified product having a melting point of 249-250 ° C. is prepared, and the purified product is recrystallized from N, N-dimethylformamide Describes an example of synthesis of brimonidine having a melting point of 252 to 253 ° C.

  Patent Documents 1 and 2 describe acid addition salts of quinoxaline derivatives such as brimonidine, and tartaric acid salt as an example. This tartrate salt is sold as a therapeutic agent for glaucoma and ocular hypertension after a pharmacological approval test. For example, Aifagan (registered trademark) ophthalmic solution 0.1% package insert (Non-Patent Document 1) describes an aqueous eye drop containing brimonidine tartrate at a concentration of 1 mg / mL. The 1% pharmaceutical interview form (Non-Patent Document 2) describes that the melting point of brimonidine tartrate is 207 to 210 ° C. as the physicochemical properties of the active ingredient.

  However, these documents do not describe anything about amorphous brimonidine tartrate.

JP-A-56-25176 (Claims, Examples, page 5, upper right column, lines 10 to 11) Patent No. 2999240 (Claims, Examples)

AIFAGAN (registered trademark) ophthalmic solution 0.1% package insert, January 2012 Aifangan (registered trademark) ophthalmic solution 0.1% pharmaceutical interview form, April 2012

  Accordingly, an object of the present invention is to provide an amorphous brimonidine tartrate salt and a method for producing the same.

  Another object of the present invention is to provide an amorphous brimonidine tartrate salt capable of improving cell membrane permeability and exhibiting excellent bioavailability and a method for producing the same.

  Another object of the present invention is to provide an amorphous brimonidine tartrate salt that can exhibit therapeutic effects (such as glaucoma and ocular hypertension treatment effects) even with a small dose, and a method for producing the same.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have dissolved brimonidine tartrate raw material in alcohol and / or water, and concentrated or lyophilized this solution, whereby brimonidine tartrate different from conventional crystals is obtained. Thus, the present inventors have found that the novel polymorph (amorphous form) is obtained and that the novel polymorph is excellent in bioavailability (bioavailability) such as cell membrane permeability.

  That is, the present invention includes amorphous (amorphous or amorphous form) brimonidine tartrate, for example, amorphous brimonidine tartrate having a decomposition point at a temperature of 163 to 167 ° C. (eg, 165 ° C.).

  The present invention includes a pharmaceutical composition comprising the amorphous brimonidine tartrate salt and a pharmacologically acceptable carrier. The present invention also includes a preventive and / or therapeutic agent for eye diseases (for example, glaucoma, ocular hypertension) containing the amorphous brimonidine tartrate as an active ingredient. Furthermore, this invention includes the manufacturing method of an amorphous brimonidine tartrate including the process of melt | dissolving a brimonidine tartrate raw material in alcohol and / or water, and concentrating or freeze-drying this solution.

  In the present specification, “brimonidine tartrate” has the chemical name 5-bromo-N- (4,5-dihydro-1H-imidazol-2-yl) quinoxalin-6-amine mono- (2R, 3R). ) -Refers to a compound that is a tartrate salt.

  In the present invention, bioavailability can be improved compared to conventional crystals. In particular, the present invention is excellent in cell membrane permeability, facilitates transfer to living tissues such as ocular tissues, and can exhibit therapeutic effects (eg, glaucoma, high intraocular pressure therapeutic effects) even with a small dose, Can improve patient compliance. Moreover, since the dose can be reduced, side effects can be reduced and safety is excellent.

1 is a powder X-ray diffraction spectrum of amorphous brimonidine tartrate of Example 1. FIG. 2 is a differential scanning calorimetric spectrum of amorphous brimonidine tartrate of Example 1. FIG.

[Amorphous brimonidine tartrate]
The amorphous brimonidine tartrate of the present invention is characterized by a powder X-ray diffraction spectrum and / or differential scanning calorimetry spectrum, and has a pattern derived from amorphous brimonidine tartrate (amorphous or amorphous). In particular, when amorphous brimonidine tartrate is included, the dissolution property and bioavailability can be improved and it can be absorbed into the living body in a short time.

  In the powder X-ray diffraction spectrum, amorphous brimonidine tartrate has substantially no diffraction peak derived from the crystal structure, and has a halo pattern derived from scattering of incident X-rays. The powder X-ray diffraction spectrum was measured using a conventional X-ray diffractometer under the conditions of a radiation source Cu K (α1), a tube voltage of 40 kV, a tube current of 40 mA, a sampling interval of 0.1 °, and a scanning speed of 10 ° / min. It can be measured.

  Amorphous brimonidine tartrate has a peak derived from the decomposition point (decomposition temperature) in differential scanning calorimetry. The decomposition point (decomposition temperature) is, for example, about 163 to 167 ° C, preferably about 164 to 166 ° C.

  The decomposition point can be measured using a differential scanning calorimeter (DSC) under conditions of a heating rate of 5 ° C./min. The melting point may be measured using a capillary.

  The present invention also discloses a mixture comprising amorphous brimonidine tartrate and crystalline brimonidine tartrate. That is, the amorphous brimonidine tartrate may be present in the form of a mixture in combination with the crystalline brimonidine tartrate, for example, in the form of a physical mixture, mixed crystal or the like. The mixture appears to be derived from amorphous brimonidine tartrate to improve the solubility of crystalline brimonidine tartrate. Crystalline brimonidine tartrate is a conventional crystal form brimonidine tartrate, for example, a peak intensity (for example, 2θ = 11.8 ° peak intensity (peak height) or integrated intensity (peak area) in a powder X-ray diffraction spectrum. )).

  The weight ratio of amorphous brimonidine tartrate and crystalline brimonidine tartrate can be selected from the range of about 1/99 to 99/1, for example, 5/95 to 99/1 (for example, 10/90 to 99 / 1), preferably 15/85 to 98/2 (for example, 20/80 to 97/3), more preferably about 25/75 to 95/5. The weight ratio is the characteristic peak intensity (for example, 2θ = 11.8 ° peak intensity (peak height) or integrated intensity (peak area)) of crystalline brimonidine tartrate in the powder X-ray diffraction spectrum. It can be calculated by comparing the case of brimonidine tartrate alone with the case of a mixture of amorphous brimonidine tartrate and crystalline brimonidine tartrate contained in various proportions.

  The average particle diameter (volume average particle diameter, etc.) of amorphous brimonidine tartrate or a mixture of amorphous brimonidine tartrate and crystalline brimonidine tartrate is not particularly limited, and is measured by, for example, a laser diffraction particle size distribution analyzer. Then, it may be about 0.5 μm to 1 mm, preferably about 1 to 500 μm (for example, 2 to 100 μm), and usually about 5 to 50 μm (for example, 5 to 30 μm).

[Method for producing amorphous brimonidine tartrate]
The method for producing amorphous brimonidine tartrate (for example, brimonidine tartrate containing at least amorphous) is not particularly limited as long as the above powder X-ray diffraction spectrum and / or differential scanning calorimetry spectrum is obtained. For example, brimonidine tartrate raw material A dissolution step (i) in which water is dissolved in water (purified water or the like) and / or alcohol, a concentration step (ii) in which the solution obtained in this step (i) is concentrated, or a step of freeze-drying (iii) (iii) ).

  Brimonidine tartrate bulk is prepared by reacting 6-amino-5-bromoquinoxaline with thiophosgene to form 5-bromo-6-isothiocyanatoquinoxaline and reacting this isothiocyanate with ethylenediamine. To form 5-bromo-6- [N- (2-aminoethyl) thioureido] quinoxaline and the thioureido compound may be prepared by cyclization in the presence of tartaric acid. For details of the method for preparing brimonidine tartrate raw material, reference can be made to JP-A-56-25176.

  In the dissolving step (i), water or alcohol may be used alone, or water and alcohol may be used in combination. Examples of the alcohol include methanol, ethanol, propanol, and isopropanol. As the alcohol, methanol or ethanol is often used. The ratio (amount used) of water (or purified water) may be, for example, 1 to 800 mL, preferably 5 to 200 mL, more preferably about 10 to 100 mL with respect to 1 g of brimonidine tartrate raw material. The ratio (amount used) of alcohol (such as methanol) may be, for example, about 10 to 2000 mL, preferably about 50 to 400 mL, and more preferably about 100 to 200 mL with respect to 1 g of brimonidine tartrate raw material. When water and alcohol are used, the weight ratio of water to alcohol is, for example, the former / the latter = 5/95 to 95/5, preferably 10/90 to 90/10, more preferably 25/75 to 75/25. It may be a degree. The drug substance may be heated to be dissolved in water (or purified water) and / or alcohol, or dissolution may be promoted by applying shearing force or ultrasonic irradiation.

  In the concentration step (ii), the concentration may be performed by spray drying, and may be performed at room temperature to under heating, for example, 20 to 60 ° C., preferably 30 to 50 ° C., more preferably about 35 to 45 ° C. Usually, it is often carried out at a temperature higher than the boiling point of water and / or alcohol at atmospheric pressure. Concentration may be performed under reduced pressure to normal pressure, for example, 30 to 110 hPa, preferably 40 to 100 hPa, and more preferably about 50 to 90 hPa. Further, the concentration rate (solvent removal rate) is, for example, about 1 to 15 mL / min, preferably 2 to 10 mL / min, and more preferably about 3 to 5 mL / min for the solution having a total amount of 150 mL.

  After concentration, you may dry as needed. Drying may be performed at room temperature to heating, for example, at 10 to 40 ° C, preferably 15 to 35 ° C, and more preferably about 20 to 30 ° C. Moreover, drying can be performed under reduced pressure to normal pressure, and is usually performed under normal pressure. The drying time is not particularly limited, and is, for example, about 1 minute to 24 hours, preferably about 5 minutes to 20 hours, and more preferably about 10 minutes to 15 hours.

  In the lyophilization step (iii), the freezing temperature is, for example, -100 ° C to -60 ° C, preferably -90 ° C to -70 ° C, more preferably about -85 ° C to -75 ° C. The freezing method may be a method for rapidly reaching the freezing temperature, and is usually performed by contacting or immersing the container containing the solution obtained in the dissolving step (i) in a cooling medium (liquid nitrogen or the like). it can. After freezing, it is dried to a predetermined pressure. The pressure is, for example, about 5 to 20 Pa, preferably about 10 to 15 Pa. The drying time is not particularly limited, and is, for example, about 1 minute to 24 hours, preferably about 5 minutes to 20 hours, and more preferably about 10 minutes to 15 hours.

  Amorphous brimonidine tartrate can be formed through the dissolution step (i) and the concentration step (ii) or freeze-drying step (iii). In such a method, amorphous brimonidine tartrate can be obtained without being mixed with crystalline brimonidine tartrate.

[Method for producing a mixture of brimonidine tartrate]
The mixture may be prepared by mixing amorphous brimonidine tartrate and crystalline brimonidine tartrate in a predetermined weight ratio.

  In addition, by reducing the concentration rate in the concentration step (ii) or mildly freeze-drying conditions in the freeze-drying step (iii), crystalline brimonidine tartrate can be produced, and amorphous brimonidine A mixture of tartrate and crystalline brimonidine tartrate can be obtained. For example, the concentration rate in the concentration step (ii) is 0.1 to 5 mL / min (for example, 0.5 to 3 mL / min) under the same reduced pressure to normal pressure as described above when the total amount of the solvent of the solution is 150 mL. Min), or about 1 to 2.5 mL / min, or in the lyophilization step (iii), the solution is frozen by gradually cooling from room temperature to the freezing temperature (for example, in a time of about 5 to 30 minutes). May be.

Brimonidine tartrate salt of the present invention is excellent in bioavailability, it is useful as adrenergic alpha ₂ receptor agonist, e.g., sedative or analgesic agents, antihypertensive agents, preferably as a preventive and / or therapeutic agent for eye diseases Available. Examples of eye diseases include glaucoma (such as open-angle glaucoma), neurodegeneration, and ocular hypertension.

  Brimonidine tartrate may be used alone as a medicine, or may be used as a combined medicine in combination with other active ingredients (physiologically active ingredients or pharmacologically active ingredients) as necessary. Other active ingredients include vitamins (vitamin A such as retinol or a salt thereof; vitamin B such as thiamine or a salt thereof; vitamin E such as tocopherol or a salt thereof), amino acids (aspartic acid or a salt thereof) ), Dry eye therapeutic agents (such as hyaluronic acid or salts thereof), glaucoma therapeutic agents (beta-blockers such as timolol or salts thereof), prostaglandin-related drugs such as unoprostone, latanoprost, travoprost, or salts thereof; brinzolamide, Carbonic anhydrase inhibitors such as dorzolamide or their salts), cataract treatment agents (such as pirenoxine, glutathione or their salts), antibacterial agents (ofloxacin, levofloxacin, norfloxacin, lomefloxacin, gatifloxacin, tosufloxacin, moxifloxacin) or Etc. These salts), antiallergic agents (cromoglycate, ketotifen, pemirolast, tranilast, ibudilast, acitazanolast, levocabastine, olopatadine, glycyrrhizinate, lysozyme, amlexanox, azulene, cyclosporin or the like salt thereof), and others. The proportion of the other active ingredient is, for example, 30 parts by weight or less, preferably 20 parts by weight or less, more preferably 10 parts by weight or less (for example, 0.01 to 5 parts by weight) with respect to 100 parts by weight of brimonidine tartrate. Degree.

  Brimonidine tartrate may be used as a pharmaceutical composition (or formulation) in combination with a carrier (such as a pharmacologically acceptable carrier). In the pharmaceutical composition of the present invention, the carrier is appropriately selected according to the form (ie, dosage form), dosage form, use, etc. of the pharmaceutical composition (or formulation). The dosage form is not particularly limited, and is a solid preparation (powder, powder, granule (granule, fine granule, etc.), pill, pill, tablet, capsule (soft capsule, hard capsule, etc.), dry syrup, Suppositories, etc.), semi-solid preparations (creams, ointments, gels, gummies, film preparations, sheet preparations, etc.), liquids (solutions, suspensions, emulsions, syrups, elixirs, lotions) , Injections, drops, etc.). Also included are sprays such as the powders and / or liquids, aerosols and the like. The capsule may be a liquid-filled capsule or a capsule filled with a solid agent such as a granule. The preparation may be a lyophilized preparation. Furthermore, the preparation of the present invention may be a preparation with controlled drug release rate (sustained release preparation, immediate release preparation). The preparations are oral preparations (eg granules, powders, tablets (sublingual tablets, orally disintegrating tablets, etc.), capsules, syrups, emulsions, suspensions, jellies, gummies, film preparations, etc.). Alternatively, it may be a parenteral preparation (inhalation agent, transdermal absorption agent, eye drop, nasal drop, ear drop etc.). Furthermore, the preparation may be a topical preparation [injection (subcutaneous injection, intravenous injection, intramuscular injection, intraperitoneal injection, etc.), suspension, ointment, patch, cataplasm] Good.

  Examples of the carrier include Japanese Pharmacopoeia (Pharmacopoeia), (1) Pharmaceutical Additive Handbook, Maruzen Co., Ltd., (1989), (2) “Pharmaceutical Additives Encyclopedia 2007” (Pharmaceutical Daily Inc., 2007) Issued in July), (3) Pharmacy, revised 5th edition, Nanedo Co., Ltd. (1997) and (4) Pharmaceutical Additives Standard 2003 (Pharmaceutical Daily Inc., August 2003) It can be selected according to the administration route and the pharmaceutical application.

  In many cases, at least one carrier selected from excipients, binders and disintegrants is used as the carrier for the solid preparation.

  Examples of excipients include sugars such as lactose, glucose, sucrose, mannitol, sorbitol, and xylitol or sugar alcohols; starch such as corn starch; polysaccharides such as crystalline cellulose (including microcrystalline cellulose); Examples thereof include silicon oxide and silicate.

  As a binder, soluble starch such as pregelatinized starch and partially pregelatinized starch; polysaccharides such as gum arabic, dextrin and sodium alginate; polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), carboxyvinyl polymer, polyacrylic acid type Synthetic polymers such as polymers, polylactic acid and polyethylene glycol; methylcellulose (MC), ethylcellulose (EC), carboxymethylcellulose (CMC), sodium carboxymethylcellulose, hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), hydroxypropylmethylcellulose ( Examples thereof include cellulose ethers such as HPMC).

  Examples of the disintegrant include carboxymethyl starch sodium, carmellose, carmellose sodium, carmellose calcium, croscarmellose sodium, crospovidone, and low-substituted hydroxypropylcellulose.

  Among oil carriers, oily carriers include animal and vegetable oils (vegetable oils such as jojoba oil, olive oil, palm oil, and cottonseed oil; animal oils such as squalane) and mineral oils (liquid paraffin, silicone oil, etc.) Etc. can be exemplified. Examples of the aqueous carrier include water (sterilized purified water or distilled water), physiological saline, Ringer's solution, glucose solution, water-soluble organic solvents (e.g., lower aliphatic alcohols such as ethanol and isopropanol), and the like.

The semi-solid preparation carrier may be selected from the solid preparation carrier and / or the liquid carrier. The carrier of the semisolid preparation may contain a lipid. Lipids include waxes (beeswax, carnauba wax, lanolin, paraffin, petrolatum, etc.), higher fatty acids (saturated or unsaturated fatty acids such as stearic acid and oleic acid), higher fatty acid esters (saturated or unsaturated fatty acid alkyl esters). , Esters of saturated or unsaturated fatty acids and polyhydric alcohols (poly C _2-4 alkylene glycol, glycerin, etc.), hardened oils, higher alcohols (saturated or unsaturated fatty alcohols such as stearyl alcohol, oleyl alcohol, etc.) And metal soaps (fatty acid metal salts such as coconut oil fatty acid sodium and calcium stearate).

  In the said pharmaceutical composition (or formulation), a well-known additive can be used suitably according to an administration route, a dosage form, etc. Examples of such additives include lubricants, disintegration aids, emulsifiers, dispersants, suspending agents, solvents, solubilizers, thickeners, pH adjusters, buffers, stabilizers, or preservatives. , Fungicides or antibacterial agents, antistatic agents, flavoring agents or masking agents, coloring agents, flavoring agents or fragrances, cooling agents, antifoaming agents, isotonic agents, soothing agents, and the like. These additives can be used alone or in combination of two or more. Examples of the liquid additive include a pH adjuster, a buffer, a stabilizer, a thickener, and an isotonic agent.

  Examples of pH adjusters include bases (alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates or hydrogen carbonates such as sodium carbonate), acids (organic acids such as acetic acid and citric acid; hydrochloric acid) And inorganic acids).

  Examples of the buffer include boric acid buffers (boric acid, borax, etc.), phosphate buffers (phosphoric acid, sodium hydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, etc.) and the like.

  Examples of the stabilizer include sodium edetate and sodium bisulfite.

  Examples of the thickener include methyl cellulose, carmellose, carmellose sodium, hydroxypropyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, chondroitin sulfate, sodium chondroitin sulfate, and pullulan.

  Isotonic agents include sugars (sorbitol, glucose, mannitol, etc.), polyhydric alcohols (glycerin, polyethylene glycol, propylene glycol, etc.), inorganic salts (sodium chloride, potassium chloride, magnesium chloride, calcium chloride, etc.), etc. It can be illustrated.

  Typical pharmaceutical compositions include solutions, semi-solid preparations and the like, and in particular, ophthalmic liquids (such as eye drops such as aqueous eye drops), ophthalmic semi-solid preparations (such as eye ointments) and the like can be exemplified. .

  The proportion (content) of brimonidine tartrate is, for example, 100 parts by weight or less, preferably 0.01 to 90 parts by weight (eg 0.05 to 80 parts by weight), more preferably about 0.1 to 50 parts by weight (for example, 0.15 to 30 parts by weight). Even if the proportion of brimonidine tartrate is small, it can exert a high pharmacological effect, improve patient compliance, and have few side effects and excellent safety.

  The pharmaceutical composition of the present invention is prepared by a conventional formulation method, for example, a production method described in the 16th revised Japanese Pharmacopeia or this production method, using an active ingredient, a carrier component, and if necessary an additive. Can be prepared by different methods.

Brimonidine tartrate salt of the invention (pharmaceutical composition, adrenergic alpha ₂ receptor agonists, including the prevention and / or therapeutic agent for eye diseases) has low toxicity, is excellent also its safety, human and non-human animals Usually, it is safely administered to mammals (eg, humans, mice, rats, rabbits, dogs, cats, cows, horses, pigs, monkeys, etc.). The dose can be appropriately selected depending on the species, age, weight and condition (general condition, medical condition, presence of complications, etc.), administration time, dosage form, administration method and the like of the administration target. In the present invention, a high therapeutic effect can be obtained even with a small dose. The frequency of administration is not particularly limited, and may be, for example, once a day, or may be multiple times a day (for example, 2 to 3 times) as necessary.

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

[Powder X-ray diffraction spectrum]
The powder X-ray diffraction spectrum was measured using a powder X-ray diffractometer (manufactured by Rigaku Corporation, sample horizontal X-ray diffractometer Ultima IV), source: Cu K (α1), tube voltage: 40 kV, tube current: 40 mA. , Sampling interval: 0.1 °, scan rate 10 ° / min. In the powder X-ray diffraction chart, the diffraction peak was searched by the second derivative method with the peak width threshold being 0.1 °.

[Differential scanning calorimetry]
Using a differential scanning calorimeter (Rigaku Co., Ltd., “DSC8230L”), differential heat and thermogravimetry were simultaneously measured under the condition of a heating rate of 5 ° C./min.

[Transmission coefficient]
(1) Cell Culture Caoc-2 cells (passage number: 41 to 43) are seeded on a membrane filter for 24 well plate (pore size: 1 μm) at a density of 1.0 × 10 ⁵ cells / cm ² for 14 days. Cultured.

(2) Measurement of cell membrane permeability The buffer was extracted and warmed to 37 ° C (apical side: Hanks' balanced salt solution (pH 6.5) containing MES at a concentration of 25 mmol / L, basal side: concentration of 25 mmol / L) And replaced with Hanks' balanced salt solution (pH 7.4) containing HEPES for 30 minutes at 37 ° C. A test substance was dissolved in a predetermined amount of 50% DMSO aqueous solution to prepare a 5 mmol / L solution, and then diluted 50-fold with apical buffer to prepare a test substance solution (final concentration: 100 μmol / L). After completion of the pre-incubation, the buffer solution was extracted, the test substance solution was added to the apical side, and 1% DMSO-containing basal buffer was added to the basal side, and incubated at 37 ° C. When a predetermined time (30, 60, 120 minutes) elapsed, 100 μL of a sample was collected from the basal side. The collected sample was measured for the concentration of the test substance in the sample by LC / MS / MS, and the cell membrane permeability coefficient (Pc) was calculated according to the following formula.

Pc (cm / sec) = (dQ / dt) / (C ₀ × S × 60)
dQ / dt: Permeation amount per unit time (nmol / min)
C ₀ : Test substance solution concentration (nmol / mL)
S: Cell culture area (= 0.3 cm ² )
In parallel with the test substance, the cell membrane permeability of the standard substance (propranol) was measured. The integrity of the monolayer used in the test was determined by measuring the cell membrane resistance before and after the test.

  The cell membrane permeability test was repeated 5 times, and statistically significant differences were tested.

  The results are shown in Table 1.

[solubility]
About the compound, 99.5% ethanol solution of each concentration (0.01, 0.05, 0.10, 0.20, 0.30 mg / mL) was prepared, and high performance liquid chromatography (column: ODS, column) A calibration curve was prepared by measuring temperature: 35 ° C., eluent: acetonitrile / 0.1% TFA (12:88), flow rate: 1.00 mL / min, detection: UV 215 nm, injection amount: 10 μL). A test sample was prepared by adding the compound of Comparative Example 1 (crystal: 212 mg, ethanol: 40 mL) and the compound of Example 1 (crystal: 300 mg, ethanol: 30 mL) to 37 ° C. ethanol (purity 99.5%). The suspension was stirred with a magnetic stirrer, sampled after a predetermined time (1, 4, 7, 10, 30, 60, 120, 180, 300, 420 minutes), and the solid content was separated by filtration. The recovered solutions for 1 minute and 4 minutes were diluted 100 times with 99.5% ethanol, and the other recovered solutions were diluted 10 times, and the contents were quantified by high performance liquid chromatography to calculate the solubility.

Comparative Example 1
Brimonidine tartrate bulk (Amatek Chemical Co.ltd.) Was used. The melting point by differential scanning calorimetry was 207-210 ° C.

Example 1 (Amorphous)
Brimonidine tartrate drug substance (50 mg) was dissolved in purified water (2.00 mL) by heating to 40 ° C. This solution was cooled by freezing in an acetone-dry ice bath and freeze-dried at room temperature with a freeze dryer (15 hours) to obtain amorphous brimonidine tartrate (total amount recovered, 50 mg).

  The powder X-ray diffraction spectrum of the amorphous brimonidine tartrate obtained in Example 1 is shown in FIG. Moreover, the spectrum which measured simultaneously the differential heat | fever (DTA) -thermogravimetry (TG) about the amorphous brimonidine tartrate obtained in Example 1 is shown in FIG. Amorphous brimonidine tartrate showed no melting point in differential scanning calorimetry and decomposed at 165 ° C. The DTA curve is a curve indicating endothermic / exothermic reaction during heating (decomposed at 165 ° C.), and the TG curve is a curve indicating weight change during heating.

  Table 1 shows the permeability coefficient and solubility results for brimonidine tartrate obtained in Example 1 and Comparative Example 1.

  As is clear from Table 1, in the Examples, the permeability coefficient is significantly large (p <0.05) and the cell membrane permeability is excellent and the solubility in ethanol is excellent as compared with the Comparative Example. Moreover, since the amorphous of Example 1 has a permeability coefficient larger than that of propranol of Reference Example 1, it can improve the human gastrointestinal absorption rate (BBRC, 175 (3), 880 1991). When the cell membrane, particularly the corneal permeability, is improved, the dose can be reduced and the burden on the patient can be reduced. Moreover, since it is excellent in solubility in ethanol used as a solubilizer or solubilizer, it can be dissolved with a small amount of ethanol. Therefore, irritation | stimulation to the skin, mucous membrane, etc. by ethanol can be reduced and a patient's burden can be reduced.

Formulation Example 1
According to the following prescription, the amorphous brimonidine tartrate obtained in Example 1 and the carrier component are mixed, the mixture is granulated by a dry granulation method, and the granulated product is granulated, thereby producing granules. Got.

[Prescription]
Brimonidine tartrate 10mg
Crystalline cellulose 780mg
Sodium carboxymethyl starch 100mg
Glycerin fatty acid ester 100mg
Talc 10mg
Total amount 1000mg
Formulation Example 2
The granules obtained in Formulation Example 1 were filled into No. 0 capsules to obtain capsules.

Formulation Example 3
According to the following prescription, the granule obtained in Preparation Example 2 and the carrier component were mixed and tableted to obtain a tablet.

[Prescription]
100 mg of granules obtained in Formulation Example 2
Crystalline cellulose 172mg
Glycerin fatty acid ester 20mg
Talc 4mg
Light anhydrous silicic acid 4mg
Total amount 300mg
Formulation Example 4
According to the following formulation, the amorphous brimonidine tartrate obtained in Example 1 and an additive are added to sterilized purified water. An eye drop was obtained by aseptically filling a container that had been washed and sterilized.

Brimonidine tartrate 0.1g
Anhydrous sodium dihydrogen phosphate 0.56g
Sodium monohydrogen phosphate 0.28g
Sodium chloride 0.26g
Benzalkonium chloride 0.005g
Sterile purified water was added to make a total volume of 100 mL.

Formulation Example 5
According to the following prescription, the amorphous brimonidine tartrate obtained in Example 1 and the base are added, adjusted to a predetermined viscosity, and aseptically filled into a container that has been washed and sterilized in an aseptic environment. Obtained.

0.1 g brimonidine tartrate obtained in the examples
80g white petrolatum
Liquid paraffin 19.9g
Total amount 100g

  The amorphous brimonidine tartrate of the present invention is useful as a prophylactic and / or therapeutic agent for various diseases because it has excellent bioavailability such as cell membrane permeability and can be easily transferred to living tissue. In particular, the present invention is useful as a prophylactic and / or therapeutic agent for eye diseases (such as glaucoma and ocular hypertension).

Claims (6)

  Amorphous brimonidine tartrate.   The amorphous brimonidine tartrate according to claim 1, having a decomposition point at a temperature of 163 to 167 ° C.   A method for producing a pharmaceutical composition by mixing the amorphous brimonidine tartrate according to claim 1 or 2 and a pharmacologically acceptable carrier.   The method according to claim 3, wherein the pharmaceutical composition is a prophylactic and / or therapeutic agent for ocular diseases. Pharmaceutical composition, glaucoma and I prophylactic and / or therapeutic agent der of at least one disease selected from ocular hypertension, claim 3 or 4 The method according Ru aqueous eye drop der.   The method for producing amorphous brimonidine tartrate according to claim 1 or 2, comprising a step of dissolving brimonidine tartrate bulk in water and spray drying or freeze drying the solution.

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