HK1235711B - Ophthalmic aqueous composition - Google Patents

Description

The present invention relates to an ophthalmic aqueous composition comprising levofloxacin, a salt thereof, or a solvate thereof; phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone; one or at least two isotonic agents; and benzalkonium chloride, wherein the ophthalmic aqueous composition has a sodium chloride content of 0. 5% (w/v) or less, and wherein the ophthalmic aqueous composition has a pH of 6.5 to 8.8.

Levofloxacin is known to inhibit bacterial DNA gyrase and topoisomerase IV to inhibit the DNA synthesis, exhibiting an antibacterial activity. Levofloxacin exhibits a broad antibacterial spectrum and a potent antibacterial action, and has already been widely used in the form of 0.5% (w/v) levofloxacin ophthalmic solution (Cravit(registered trademark) ophthalmic solution 0.5%) . This ophthalmic solution contains levofloxacin as an active ingredient, as well as sodium chloride and a pH adjuster as additives . The ophthalmic solution is adjusted to have a pH of 6.2 to 6.8 and an osmotic pressure ratio of 1.0 to 1.1. The solution has a clear appearance.

Meanwhile, dexamethasone is a synthetic corticosteroid having a potent anti-inflammatory action. Among water-soluble ester derivatives thereof, particularly dexamethasone sodium phosphate has been widely used in the form of 0.1% (w/v) dexamethasone sodium phosphate ophthalmic solution (Orgadrone(registered trademark) ophthalmic solution 0.1%). This ophthalmic solution contains dexamethasone sodium phosphate as an active ingredient, as well as benzalkonium chloride, sodium edetate hydrate, boric acid, borax, and an isotonic agent as additives. The ophthalmic solution is adjusted to have a pH of 7.4 to 8.4 and be iso-osmotic. The solution has a clear appearance.

Generally, in making a drug in the form of an ophthalmic aqueous composition such as an ophthalmic solution, there are many problems to be solved, including drug stability, drug migration, and so on.

Japanese Patent No. 4758893 states that blending levofloxacin at a concentration of 1.0 to 3.0% (w/v) with glycerin at such a concentration (2 to 2.5% (v/v)) as to render the composition substantially iso-osmotic enhances the efficacy of antimicrobial preservation.

Further, SK 500 882 014 U1 describes eye drops containing broad-spectrum antibiotics and local glucocorticoid.

However, there has been no known ophthalmic aqueous composition which contains levofloxacin, a salt thereof, or a solvate thereof and dexamethasone, an ester thereof, or a salt thereof, and which solves the problems with drug stability, drug migration, and so on.

An object of the present invention is to provide an ophthalmic aqueous composition as claimed comprising levofloxacin, a salt thereof, or a solvate thereof; and phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone, the ophthalmic aqueous composition being excellent in drug stability and/or drug migration and having a clear appearance.

The present inventors have earnestly studied the formulations of ophthalmic aqueous compositions containing levofloxacin, a salt thereof, or a solvate thereof; and phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone.

As a result, the inventors have found out that incorporating one or at least two isotonic agents but substantially no sodium chloride makes a clear ophthalmic aqueous composition excellent in stability with suppressed insoluble deposit formation during the storage.

Further, the inventors have found out that adjusting the osmotic pressure ratio of such a composition to a low osmotic pressure, that is, adjusting the osmotic pressure ratio to 0.8 or less, enhances the drug migration of dexamethasone. These findings have led to the completion of the present invention.

Specifically, the present invention relates to the embodiments characterized in the appended claims. Any subject-matter falling outside the scope of the claims is provided for information purposes only.

As described herein, the ophthalmic aqueous composition comprises levofloxacin, a salt thereof, or a solvate thereof; phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone; one or at least two isotonic agents, and benzalkonium chloride, but the ophthalmic aqueous composition is substantially free of sodium chloride. This makes it possible to provide a clear ophthalmic aqueous composition excellent in stability with suppressed insoluble deposit formation during the storage.

Moreover, it is possible to provide a clear ophthalmic aqueous composition with enhanced drug migration of dexamethasone by making the osmotic pressure ratio of the composition to 0.8 or less.

Further, the composition is useful against inflammatory diseases of an outer ocular area or an anterior segment or bacterial infections of an outer ocular area or an anterior segment, such as blepharitis, dacryocystitis, stye, conjunctivitis, allergic conjunctivitis, phlyctenular conjunctivitis, spring catarrh, tarsadenitis, keratitis, blepharokeratoconjunctivitis, superior limbic keratoconjunctivitis, filamentary keratitis, epidemic keratoconjunctivitis, corneal ulcer, scleritis, episcleritis, iritis, iridocyclitis, anterior uveitis, and postoperative inflammation.

Levofloxacin is a compound represented by the following chemical structural formula (I).

A salt of levofloxacin is not particularly limited, as long as it is a pharmaceutically acceptable salt. Examples thereof include salts with an inorganic acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, sulfuric acid, or phosphoric acid; salts with an organic acid such as acetic acid, fumaric acid, maleic acid, succinic acid, citric acid, tartaric acid, adipic acid, gluconic acid, glucoheptonic acid, glucuronic acid, terephthalic acid, methanesulfonic acid, lactic acid, hippuric acid, 1,2-ethanedisulfonic acid, isethionic acid, lactobionic acid, oleic acid, pamoic acid, polygalacturonic acid, stearic acid, tannic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, sulfuric acid lauryl ester, methyl sulfate, naphthalenesulfonic acid, or sulfosalicylic acid; quaternary ammonium salts with methyl bromide, methyl iodide, or the like; salts with a halogen ion such as a bromine ion, a chlorine ion, or an iodine ion; salts with an alkali metal such as lithium, sodium, or potassium; salts with an alkaline earth metal such as calcium or magnesium; salts with a metal such as iron or zinc; salts with ammonia; salts with an organic amine such as triethylenediamine, 2-aminoethanol, 2,2-iminobis(ethanol), 1-deoxy-1-(methylamino)-2-D-sorbitol, 2-amino-2-(hydroxymethyl)-1,3-propanediol, procaine, or N,N-bis(phenylmethyl)-1,2-ethanediamine; and the like.

In a case where levofloxacin, a salt thereof, or a solvate thereof undergoes proton tautomerization, the tautomers are also included herein.

A solvate of levofloxacin or a salt thereof is not particularly limited, as long as it is a pharmaceutically acceptable solvate. Examples thereof include hydrates (such as hemihydrates, monohydrates, dihydrates), organic solvates, and the like. Preferable are hydrates (hemihydrates, monohydrates, or dihydrates), and more preferable are hemihydrates.

In a case where levofloxacin, a salt thereof, or a solvate thereof exhibits polymorphism and a polymorphic group (polymorphic system) exists, the polymorphs and the polymorphic group (polymorphic system) are also included herein. Here, the polymorphic group (polymorphic system) means the crystal form in each stage in a case where the crystal form changes according to the conditions in production, crystallization, storage, and the like of the crystal, and to the state (note that this state also includes a state of being prepared into a pharmaceutical preparation), as well as the entire process.

Levofloxacin, a salt thereof, or a solvate thereof can be produced according to the methods described in Japanese Examined Patent Application Publication Nos. Hei 3-27534 and Hei 7-47592 . Additionally, commercially-available levofloxacin hydrochloride (e.g., manufactured by Wako Pure Chemical Industries, Ltd.; distributor code: 121-05943) can also be used.

The content of levofloxacin, a salt thereof, or a solvate thereof is not particularly limited, as long as the content is sufficient to exhibit a desired efficacy. The content can be adjusted as appropriate depending on: the disease to be treated and the symptom; the age and body weight of a patient; the content of phosphate ester of dexamethasone, or of a salt of the phosphate ester of dexamethasone, which is one active ingredient of the ophthalmic aqueous composition described herein; the content of the other additive(s); the osmotic pressure (osmotic pressure ratio) of the ophthalmic aqueous composition; and so forth. The content of levofloxacin, a salt thereof, or a solvate thereof is for example 0.3 to 5% (w/v), preferably 0.3 to 3% (w/v), more preferably 0.3 to 1.5% (w/v), and particularly preferably 0.5 to 1.5% (w/v).

Dexamethasone is a compound represented by the following chemical structural formula (IIa).

Examples of esters of dexamethasone include dexamethasone acetate, dexamethasone propionate, dexamethasone valerate, dexamethasone palmitate, dexamethasone metasulfobenzoate, dexamethasone cipecilate, dexamethasone phosphate, and the like. The ophthalmic aqueous composition of the invention comprises phosphate ester of dexamethasone or a salt of the phosphate ester of dexamethasone.

Examples of salts of dexamethasone, or of salts of an ester of dexamethasone, include salts with an inorganic acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, sulfuric acid, or phosphoric acid; salts with an organic acid such as acetic acid, fumaric acid, maleic acid, succinic acid, citric acid, tartaric acid, adipic acid, gluconic acid, glucoheptonic acid, glucuronic acid, terephthalic acid, methanesulfonic acid, lactic acid, hippuric acid, 1,2-ethanedisulfonic acid, isethionic acid, lactobionic acid, oleic acid, pamoic acid, polygalacturonic acid, stearic acid, tannic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, sulfuric acid lauryl ester, methyl sulfate, naphthalenesulfonic acid, or sulfosalicylic acid; quaternary ammonium salts with methyl bromide, methyl iodide, or the like; salts with a halogen ion such as a bromine ion, a chlorine ion, or an iodine ion; salts with an alkali metal such as lithium, sodium, or potassium; salts with an alkaline earth metal such as calcium or magnesium; salts with a metal such as iron or zinc; salts with ammonia; salts with an organic amine such as triethylenediamine, 2-aminoethanol, 2,2-iminobis(ethanol), 1-deoxy-1-(methylamino)-2-D-sorbitol, 2-amino-2-(hydroxymethyl)-1,3-propanediol, procaine, or N,N-bis(phenylmethyl)-1,2-ethanediamine; and the like.

The ophthalmic aqueous composition of the invention comprises phosphate ester of dexamethasone or a salt of the phosphate ester of dexamethasone. Preferable are salts with an alkali metal, and more preferable is a salt with sodium. Dexamethasone sodium phosphate is a compound represented by the following chemical structural formula (IIb) .

In a case where the phosphate ester of dexamethasone or the salt of the phosphate ester of dexamethasone undergoes proton tautomerization, the tautomers are also included herein.

In a case where a solvate exists in the phosphate ester of dexamethasone or the salt of the phosphate ester of dexamethasone, such solvates are also included herein. The solvate of the phosphate ester of dexamethasone or the salt of the phosphate ester of dexamethasone is not particularly limited, as long as it is a pharmaceutically acceptable solvate. Examples thereof include hydrates (such as hemihydrates, monohydrates, dihydrates), organic solvates, and the like.

In a case where the phosphate ester of dexamethasone or the salt of the phosphate ester of dexamethasone exhibits polymorphism and a polymorphic group (polymorphic system) exists, the polymorphs and the polymorphic group (polymorphic system) are also included herein. Here, the polymorphic group (polymorphic system) means the crystal form in each stage in a case where the crystal form changes according to the conditions in production, crystallization, storage, and the like of the crystal, and to the state (note that this state also includes a state of being prepared into a pharmaceutical preparation), as well as the entire process.

The phosphate ester of dexamethasone or the salt of the phosphate ester of dexamethasone can be produced by a normal method in the field of synthetic organic chemistry. Moreover, commercially-available products can also be used. For example, dexamethasone sodium phosphate manufactured by Wako Pure Chemical Industries, Ltd. (distributor code: 554-74381) can also be used.

Further, the content of phosphate ester of dexamethasone or of a salt of the phosphate ester of dexamethasone is not particularly limited, as long as the content is sufficient to exhibit a desired efficacy. The content can be adjusted as appropriate depending on: the disease to be treated and the symptom; the age and body weight of a patient; the content of levofloxacin, a salt thereof, or a solvate thereof, which is one active ingredient of the ophthalmic aqueous composition described herein; the content of the other additive (s); the osmotic pressure (osmotic pressure ratio) of the ophthalmic aqueous composition; and so forth. The content of phosphate ester of dexamethasone or of a salt of the phosphate ester of dexamethasone is for example 0.01 to 0.3% (w/v), preferably 0.025 to 0.2%, more preferably 0.05 to 0.12% (w/v), and particularly preferably 0.10 to 0.12% (w/v).

As described herein, an isotonic agent is not particularly limited, as long as it is a pharmaceutically acceptable isotonic agent. Examples thereof include ionic isotonic agents, nonionic isotonic agents, and the like.

Examples of the ionic isotonic agents include inorganic salts and organic salts.

Examples of the inorganic salts include disodium phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, sodium hydrogen sulfite, sodium sulfite, sodium thiosulfate, magnesium sulfate, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, boric acid, borax, and the like.

Examples of the organic salts include potassium acetate, sodium acetate, sodium hydrogen carbonate, sodium carbonate, and the like.

Examples of the nonionic isotonic agents include polyhydric alcohols having two or more alcoholic hydroxy groups in single molecules, and the like.

Specific examples of the polyhydric alcohols include, for example, glycerin, propylene glycol, polyethylene glycol, glucose, trehalose, sucrose, xylitol, sorbitol, and the like. Among these isotonic agents, the nonionic isotonic agents are preferably polyhydric alcohols such as glycerin, propylene glycol, and polyethylene glycol; the ionic isotonic agents are preferably inorganic salts such as boric acid and borax; more preferable are glycerin and borax; particularly preferable is glycerin.

Moreover, one of the isotonic agents described herein may be used alone, or two or more thereof may be used in any combination.

Further, the concentration of the isotonic agent described herein can be adjusted as appropriate in consideration of: the influence on the drug and/or the other additive(s); and the adjustment of the osmotic pressure (osmotic pressure ratio) of the ophthalmic aqueous composition to a particular range. In the case where the isotonic agent described herein is a nonionic isotonic agent, the concentration is for example 10 to 1000 mmol/L, preferably 20 to 500 mmol/L, more preferably 20 to 300 mmol/L, and particularly preferably 20 to 200 mmol/L. In the case of an ionic isotonic agent, the concentration of all ions including cations and anions but not those of the drug is 10 to 1000 (mmol/L), preferably 20 to 500 (mmol/L), more preferably 20 to 300 (mmol/L), and particularly preferably 20 to 200 (mmol/L).

Furthermore, in the case where the isotonic agent described herein is a nonionic isotonic agent or a polyhydric alcohol, particularly glycerin, the content can be adjusted as appropriate in consideration of the influence on the drug, the other additive(s), and/or the osmotic pressure (osmotic pressure ratio) of the ophthalmic aqueous composition. The content of a nonionic isotonic agent or a polyhydric alcohol, particularly glycerin (the molecular weight: 92.09), is for example 0.01 to 10% (w/v), preferably 0.05 to 5% (w/v), more preferably 0.1 to 3.0% (w/v), furthermore preferably 0.3 to 3.0% (w/v), and particularly preferably 0.3 to 1.9% (w/v).

The ophthalmic aqueous composition described herein is substantially free of sodium chloride. Here, the phrase "substantially free of" means that the content does not adversely influence the stability, for example, physical stability, of the ophthalmic aqueous composition. Specifically, the content of sodium chloride is 0.5% (w/v) or less, 0.4% (w/v) or less, or 0.3% (w/v) or less, more preferably 0.27% (w/v) or less, furthermore preferably 0.2% (w/v) or less, still furthermore preferably 0.18% (w/v) or less, and particularly preferably 0.14% (w/v) or less.

The pH of the ophthalmic aqueous composition described herein is of 6.5 to 8.8.

The ophthalmic aqueous composition described herein can be blended as necessary with a base. The base is not particularly limited, as long as it is a pharmaceutically acceptable base. Examples thereof can include sodium hydroxide, potassium hydroxide, monoethanolamine, diethanolamine, triethanolamine, trometamol, meglumine, and the like.

In addition, the ophthalmic aqueous composition described herein can also be blended as necessary with an acid such as an organic acid or an inorganic acid.

Moreover, one of these pH adjusters may be used alone, or two or more thereof may be used in any combination.

The osmotic pressure ratio of the ophthalmic aqueous composition described herein means an osmotic pressure ratio of the composition to saline. Note that the value can be measured by a usual method. For example, the measurement is possible according to the method described in the section of osmotic pressure measurement method (Osmolarity Determination) in The Japanese Pharmacopoeia, Fifteenth Edition.

Moreover, the osmotic pressure ratio of the ophthalmic aqueous composition described herein is not particularly limited, as long as it is within a range acceptable to the living body. The osmotic pressure ratio is for example 0.01 to 3.5, preferably 0.01 to 2.0, more preferably 0.1 to 1.5, furthermore preferably 0.3 to 1.2, and particularly preferably 0.3 to 0.8.

Generally, the osmotic pressure ratio of an aqueous composition is influenced greatly to some extent by the contents of a drug and an additive contained in the aqueous composition. As described herein, the osmotic pressure ratio can be adjusted to the above-described ranges by adjusting as appropriate the content of each substance that may influence the osmotic pressure.

Further, the osmotic pressure of the ophthalmic aqueous composition described herein is not particularly limited, as long as it is within a range acceptable to the living body. The osmotic pressure is for example 10 to 1000 mOsm, preferably 30 to 500 mOsm, more preferably 60 to 340 mOsm, furthermore preferably 60 to 260 mOsm, and particularly preferably 60 to 230 mOsm.

The ophthalmic aqueous composition described herein can be further blended with one or at least two thickening agents without particular limitation, as long as the thickening agent(s) are pharmaceutically acceptable.

Examples of the thickening agent described herein include cellulose polymers (such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropylmethyl cellulose), vinyl polymers (such as polyvinylpyrrolidone), sugars (mucopolysaccharides such as hyaluronic acid and salts thereof; polysaccharides such as gellan gum, sodium alginate, dextran, cyclodextrin), oxyalkylene polymers (polyoxyethylene-polyoxypropylene block copolymers), and the like.

The molecular weight of the thickening agent described herein can be selected, for example, from a range of approximately 0.5 × 10⁴ to 100 × 10⁴ as the number average molecular weight.

Moreover, the content of the thickening agent described herein can be adjusted as appropriate in consideration of the influence on the drug, the other additive (s), and/or the osmotic pressure (osmotic pressure ratio). The content of the thickening agent described herein is for example 0.001 to 10% (w/v), preferably 0.01 to 5% (w/v), more preferably 0.03 to 3% (w/v), furthermore preferably 0.05 to 2.5% (w/v), and particularly preferably 0.1 to 2.0% (w/v).

The ophthalmic aqueous composition described herein can be blended as necessary with a nonionic surfactant. The nonionic surfactant is not particularly limited, as long as it is within a pharmaceutically acceptable range. Examples thereof include polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene castor oil derivatives, polyoxyethylene polyoxypropylene glycols, sucrose fatty acid esters, and the like. The polyoxyethylene fatty acid esters include polyoxyl 40 stearate, and the like. The polyoxyethylene sorbitan fatty acid esters include polysorbate 80, polysorbate 60, polysorbate 40, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan trioleate, polysorbate 65, and the like. The polyoxyethylene castor oil derivatives include polyoxyethylene hydrogenated castor oil 10, polyoxyethylene hydrogenated castor oil 40, polyoxyethylene hydrogenated castor oil 50, polyoxyethylene hydrogenated castor oil 60, polyoxyl 5 castor oil, polyoxyl 9 castor oil, polyoxyl 15 castor oil, polyoxyl 35 castor oil, polyoxyl 40 castor oil, and the like. The polyoxyethylene polyoxypropylene glycols include polyoxyethylene (160) polyoxypropylene (30) glycol, polyoxyethylene (42) polyoxypropylene (67) glycol, polyoxyethylene (54) polyoxypropylene (39) glycol, polyoxyethylene (196) polyoxypropylene (67) glycol, polyoxyethylene (20) polyoxypropylene (20) glycol, and the like.

Moreover, one of these nonionic surfactants may be used alone, or two or more thereof may be used in any combination.

The ophthalmic aqueous composition described herein can be blended as necessary with a buffer. The buffer is not particularly limited, as long as it is within a pharmaceutically acceptable range. Examples thereof include phosphoric acid or salts thereof, boric acid or salts thereof, citric acid or salts thereof, acetic acid or salts thereof, carbonic acid or salts thereof, tartaric acid or salts thereof, ε-aminocaproic acid, trometamol, and the like. The phosphoric acid salts include sodium phosphate, sodium dihydrogen phosphate, disodium phosphate, potassium phosphate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, and the like. The boric acid salts include borax, sodium borate, potassium borate, and the like. The citric acid salts include sodium citrate, disodium citrate, and the like. The acetic acid salts include sodium acetate, potassium acetate, and the like. The carbonic acid salts include sodium carbonate, sodium hydrogen carbonate, and the like. The tartaric acid salts include sodium tartrate, potassium tartrate, and the like.

Moreover, one of these buffers may be used alone, or two or more thereof may be used in any combination.

The ophthalmic aqueous composition described herein can be blended as necessary with a stabilizer. The stabilizer is not particularly limited, as long as it is within a pharmaceutically acceptable range. Examples thereof include edetic acid, sodium edetate, and the like.

Moreover, one of these stabilizers may be used alone, or two or more thereof may be used in any combination.

The ophthalmic aqueous composition of the invention comprises benzalkonium chloride as a preservative.

Examples of other preservatives include sorbic acid, potassium sorbate, benzethonium chloride, methyl paraoxybenzoate, propyl paraoxybenzoate, chlorobutanol, boric acid, borax, and the like.

Benzalkonium chloride may be used alone or in combination with one or more of the above-mentioned preservatives.

Further, the content of the preservative described herein can be adjusted as appropriate in consideration of the influence on the drug, the other additive (s), and/or the osmotic pressure (osmotic pressure ratio). The content of the preservative described herein is for example 0.001 to 0.02% (w/v), preferably 0.001 to 0 . 01% (w/v), and more preferably 0.001 to 0.005% (w/v) .

Herein, the term "aqueous composition" means a composition having water as a base.

Herein, the term "ophthalmic aqueous composition" means an aqueous composition used in an ophthalmic topical administration. In the "ophthalmic aqueous composition", more than 80% (w/v) of the composition is water, and preferably more than 90% (w/v) of the composition is water.

Examples of the dosage form of the ophthalmic aqueous composition described herein can include an ophthalmic injection and an eye drop, and the dosage form is preferably an eye drop.

The ophthalmic aqueous composition described herein has a sufficient stability for use as a pharmaceutical drug.

The disease against which the ophthalmic aqueous composition described herein is applicable is not particularly limited. Examples thereof can include inflammatory diseases of an outer ocular area or an anterior segment or bacterial infections of an outer ocular area or an anterior segment, such as blepharitis, dacryocystitis, stye, conjunctivitis, allergic conjunctivitis, phlyctenular conjunctivitis, spring catarrh, tarsadenitis, keratitis, blepharokeratoconjunctivitis, superior limbic keratoconjunctivitis, filamentary keratitis, epidemic keratoconjunctivitis, corneal ulcer, scleritis, episcleritis, iritis, iridocyclitis, anterior uveitis, and postoperative inflammation.

The number of administrations of the ophthalmic aqueous composition described herein is not particularly limited, as long as it is sufficient to exhibit a desired efficacy. The number can be selected as appropriate depending on: the disease to be treated and the symptom; and the age and body weight of a patient. For example, the instillation is possible at a dose of 1 to several drops (for example, 1 to 3 drops, preferably 1 drop) once to several times (for example, 1 to 6 times) per day.

As the method for preparing the ophthalmic aqueous composition described herein, the composition can be prepared by generally used methods.

Herein, the term "clear" means that the target composition is transparent when a glass container (such as glass vial, glass ampoule) is filled with the composition and visually checked.

[Examples]

Hereinafter, the results of test examples will be described. However, these examples are for better understanding of the present invention, and are not to limit the scope of the present invention. Examples 1 to 8, and 10 to 16 are not within the scope of the present invention and are included for comparative reasons only. The Comparative Examples 1-3 and Reference Example 1 are also not according to the invention.

[Test Example 1] Physical Stability Test

Whether the appearance of the ophthalmic aqueous composition described herein changed or not during the storage was visually checked to evaluate the physical stability.

(Sample Preparation) Example 1:

According to the formulation shown in Table 1, an ophthalmic solution of Example 1 was prepared. Specifically, 0 . 5 g of levofloxacin hemihydrate, 0.1 g of dexamethasone sodium phosphate, and 2.5 g of glycerin were dissolved in purified water. A sodium hydroxide solution was added thereto to adjust the pH to 7.0. The whole amount was made 100 mL.

Examples 2 to 9, Comparative Examples 1 to 3, and Reference Example 1:

According to the formulations shown in Table 1, ophthalmic solutions of Examples 2 to 9, Comparative Examples 1 to 3, and Reference Example 1 were prepared in the same manner as in Example 1.

(Test Method)

A colorless, transparent plastic container (5 mL) was filled with one of the ophthalmic solutions of Examples 1 to 9, Comparative Examples 1 to 3, and Reference Example 1. Whether the appearance changed or not was visually checked immediately after the preparation or after the storage at room temperature or 60°C for 7 days, to evaluate the physical stability. O indicates a case where no insoluble deposit was observed, resulting in a clear solution. X indicates a case where an insoluble deposit was observed, resulting in an unclear solution.

(Test Result)

Table 1 shows the test result.

The result in Test Example 1 showed that the ophthalmic aqueous compositions were clear solutions with suppressed insoluble deposit formation, the ophthalmic aqueous compositions each containing: levofloxacin, a salt thereof, or a solvate thereof; phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone; an isotonic agent; and substantially no sodium chloride.

[Test Example 2] Thermal Stability Test

The thermal stabilities of levofloxacin hemihydrate and dexamethasone sodium phosphate in the ophthalmic aqueous compositions described herein were examined.

(Sample Preparation) Example 4:

According to the formulation shown in Table 1, an ophthalmic solution of Example 4 was prepared in the same manner as in Test Example 1.

(Test Method)

The ophthalmic solution of Example 4 was stored at 40°C for two weeks and one month or at 25°C for one month. Then, the contents of levofloxacin and dexamethasone sodium phosphate in the ophthalmic solution were quantified by using high-performance liquid chromatography (HPLC) to calculate the residual ratios.

(Test Result)

Table 2 shows the test result. Table 2

		Example 4
Storage conditions		40°C, 2 weeks	40°C, 1 month	25°C, 1 month
residual ratio (%)	levofloxacin hemihydrate	101	101	101
	dexamethasone sodium phosphate	100	100	100

As is apparent from Table 2, the ophthalmic solution of Example 4 exhibited a stable result after two weeks and one month at 40°C or after one month at 25°C. Note that, before and after the test, no insoluble deposit was observed, and the ophthalmic solution was a clear solution.

[Test Example 3] Drug Migration Test

The migration of dexamethasone in aqueous humor was examined using the ophthalmic aqueous compositions described herein.

(Sample Preparation) Examples 4, 9 to 16:

According to the formulations shown in Table 3, ophthalmic solutions of Examples 4, 9 to 16 were prepared in the same manner as in Test Example 1.

(Test Method)

The dexamethasone concentration in the aqueous humor was measured by the LC-MS/MS method when the ophthalmic solutions of Examples 4, 9 to 16 were each instilled into eyes of JW male white rabbits once.

(Administration Method and Measurement Method)

1. 1) With MICROMAN, 50 µL of one of the ophthalmic solutions was instilled onto the corneas.
2. 2) While the rabbits were each put in a holder for a predeterminedperiod under non-anesthesia, a pentobarbital preparation (product name: Somnopentyl injection) was injected into the auricular vein for euthanasia.
3. 3) After the eyeballs were washed with a saline, the aqueous humor was collected.
4. 4) A pretreatment was performed using 50 µL of the collected aqueous humor per eye, and the dexamethasone concentration in the aqueous humor was then measured by the LC-MS/MS method.

(Test Result)

Table 3 shows the dexamethasone concentrations (Cmax, average values of four or six eyes) in the aqueous humor. Table 3

(Unit: g/100 mL)
Example
9	10	11	4	12	13	14	15	16
levofloxacin hemihydrate	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5
dexamethason e sodium pho sphate	0.1	0.1	0.1	0.1	0.1	0.1	0.1	0.1	0.1
glycerin	1.3	2.3	2.3	1.3	0.46	2.3	0.5	0.5	-
borax	-	-	-	-	-	-	-	-	1.0
hydroxyethyl cellulose	-	-	-	-	-	0.2	-	-	-
gellan gum	-	-	-	-	-	-	0.6	-	-
sodium algin ate	-	-	-	-	-	-	-	0.3	-
benzalkonium chloride	0.005	-	-	-	-	-	-	-	-
trometamol	-	-	-	-	-	-	q.s.	-	-
sodium hydro xide	q.s.	q.s.	q.s.	q.s.	q.s.	q.s.	-	q.s.	q.s.
purified wat er	q.s.	q.s.	q.s.	q.s.	q.s.	q.s.	q.s.	q.s.	q.s.
pH	8.0	8.8	8.3	8.0	8.3	8.3	8.3	8.3	8.3
osmotic pres sure ( mOsm)	165	289	283	170	74	283	93	83	185
osmotic pres sure ratio	0.6	1.0	1.0	0.6	0.3	1.0	0.3	0.3	0.6
dexamethason e concentrat ion Cmax (ng /mL) in aque ous humor	73.5	62.7	64.8	76.8	76.4	106.5	82.9	83.7	96.1

As shown in Table 3, the ophthalmic solutions of Examples 4, 9 to 16 exhibited high dexamethasone mobilities in the aqueous humor.

The ophthalmic aqueous composition described herein is a clear solution excellent in drug stability and drug migration. Moreover, the composition is useful against inflammatory diseases of an outer ocular area or an anterior segment or bacterial infections of an outer ocular area or an anterior segment.

Claims (12)

1. An ophthalmic aqueous composition comprising levofloxacin, a salt thereof, or a solvate thereof; phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone; one or at least two isotonic agents; and benzalkonium chloride, wherein the ophthalmic aqueous composition has a sodium chloride content of 0.5% (w/v) or less, and wherein the ophthalmic aqueous composition has a pH of 6.5 to 8.8.
2. The ophthalmic aqueous composition according to claim 1, wherein the ophthalmic aqueous composition further comprises a buffer and/or a pH adjuster.
3. The ophthalmic aqueous composition according to claim 1 or 2, wherein the ophthalmic aqueous composition has an osmotic pressure ratio of the composition to saline of 1.2 or less.
4. The ophthalmic aqueous composition according to claim 1 or 2, comprising the isotonic agent(s) at such a concentration as to adjust the osmotic pressure of the ophthalmic aqueous composition to a range of 60 to 340 mOsm.
5. The ophthalmic aqueous composition according to claim 1, wherein the isotonic agent(s) are a nonionic isotonic agent or an ionic isotonic agent.
6. The ophthalmic aqueous composition according to claim 5, wherein the nonionic isotonic agent is a polyhydric alcohol.
7. The ophthalmic aqueous composition according to claim 6, wherein the polyhydric alcohol is one or at least two selected from the group consisting of glycerin, propylene glycol, and polyethylene glycol.
8. The ophthalmic aqueous composition according to claim 5, wherein the ionic isotonic agent is selected from the group consisting of inorganic salts and organic salts.
9. The ophthalmic aqueous composition according to claim 5, wherein the ionic isotonic agent is an inorganic salt.
10. The ophthalmic aqueous composition according to claim 9, wherein the inorganic salt is boric acid or borax.
11. The ophthalmic aqueous composition according to claim 1, wherein the concentration of levofloxacin, a salt thereof, or a solvate thereof is 0.5% to 1.5% (w/v); the concentration of the phosphate ester of dexamethasone, or a salt of the phosphate ester of dexamethasone is 0.025% to 0.2% (w/v); the concentration of the benzalkonium chloride is 0.001% to 0.02% (w/v); and the ophthalmic aqueous composition has an osmotic pressure ratio of the composition to saline of 0.3 to 1.2.
12. The ophthalmic aqueous composition according to any one of claims 1 to 11, which is an eye drop.