NZ327092A - Topical medicaments containing nimesulide - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number 327092 New Zealand No 327092 International No. PCT/JP96/00849 TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates 05 10 1995, Complete Specification Filed 01 04 1996 Classification (6) A61K31/18, A61K9/06, A61K47/10,14,16,30,44 Publication date 29 September 1999 Journal No 1444 ::o DRAWINGS NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention External Antnnflamatory Agent Name, address and nationality of applicant(s) as in international application form HELSINN HEALTHCARE SA, a Swiss company of Via Pian Scairolo, 6912 Pazzallo, Switzerland New Zealand No International No 327092 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention Antiflammatory agent for external use Name, address and nationality of applicant(s) as in international application form HELSINN HEALTHCARE SA, a Swiss company of Via Plan Scairolo, 691 2 Pazzallo, Switzerland X ^ rn f• I' ' ) SPECIFICATION ^ 4,, Antiinflammatory agent for external use Field of the Industrial Use The present invention relates to an antiinflammatory agent for external (topical)use comprising mmesulide as an active ingredient In particular, the present invention relates to an antiinflammatory agent for external use comprising nimesulide as an active ingredient and a base component wherein the nimesulide is mixed in a dispersed state in the base component, as well as to a process for preparing.jfcjji=f same Prior Art Non-steroidal antiinflammatory preparations have a disadvantage that, when orally administered, they cause gastrointestinal tract disorders. In order to avoid this disadvantage, various studies have been made to develop antiinflammatory agent for external use and several commercial products have been provided for clinical use However, the antiinflammatory agent for external use hitherto developed have insufficient clinical effects even if they show effects m the basic tests which is one of the non-steroidal antiinflammatory agents, was first synthesized by Riker Co. m the United States and then developed as an oral preparation in Europe by Helsinn Nimesulide (4-mtro-2-phenoxymethanesulfonanilide), - 1Q- Co m Switzerland Being different from the conventional acidic antiinflammatory agents, it is known that nimesulide selectively inhibits PGE2 (C0X2) and this is a new type pharmaceutical agent expected to take effects m clinical use As the Drior art regarding nimesulide, the substance I patent described in U S Patent No 3,480,597 and process patents described m the examined Japanese patent publication (Kokoku) Sho-58-35989, the examined Japanese patent: publication (Kokoku) Sho-58-50984 and the examined Japanese patent publication (Kokoku) Sho-59-44311 may be J cited. However, these prior art references do not have descriptions or working examples regarding the actual pharmaceutical preparations, although they mention dosage forms such as capsule, cream, gel, cape, and the like.

In addition, the laid-open Japanese patent application (Kohyo) Hei-6-502842 based on the international patent application may be cited as a reference relating to the pharmaceutical preparation of nimesulide. This patent is to prepare an inclusion compound of nimesulide with cyclodextrm to make nimesulide water-soluble so as to increase water-solubility and to increase absorption of nimesulide in the gastrointestinal tract Therefore, its object is not the external use. Thus, no reference is known which illustratively discloses use of nimesulide as an INTELLECTUAL PROPERTY OFFICE OF NZ 2 h 3E? 1998 external preparation, and no case is known with respect to the actual external use of nimesulide in a particular dosage form It would be due to the fact that, although nimesulide has pharmacological effects equal to or higher than those of indomethacin which is regarded as a potent antiinflammatory agent, it has several unsolved problems when topically applied as an external preparation That is, (1) nimesulide is hardly soluble and is not easily dissolved in water and various organic solvents. (2) A solvent which has strong solubilizing ability should be mixed to dissolve nimesulide, causing problems such as skin irritation, chapped skin, itch, and flare. (3) Even if nimesulide is dissolved, the resulting pharmaceutical preparation becomes deep yellow and thus its appearance becomes bad. (4) The pharmaceutical preparation applied soils clothes that contact the preparation.

Thus, there is a situation that the attempt to use nimesulide as the external preparation was abandoned Problems to be Solved bv the Invention The object of the present invention is to obtain an antiinflammatory agent for external use including nimesulide for topical use, which is a nimesulide external preparation showing excellent absorption and having no problem in coloring and skin safety, or at least to provide the public with a useful choice 3 iNTELLhCTiluTROPERTY OFFICE OF NZ 2 9 JUL 1999 RECEIVED Means for Solving the Problems As a result of extensive studies taking the above-described disadvantages of nimesulide as an external preparation into consideration, the present inventors found that the above-described disadvantages are all solved when nimesulide is mixed in a dispersed state m a base t component, and completed the present invention That is, when nimesulide is mixed in a dispersed state in a base component, it surprisingly shows pharmacological effects equal to or higher than those of the pharmaceutical preparation in which nimesulide is mixed in a dissolved J form. In addition, the amount of a solubilizing agent can be reduced and therefore the skin safety is improved Furthermore, it is proved that the coloring of the pharmaceutical preparation does not occur, which is different from the completely dissolved-type pharmaceutical preparation That is, all the above-described problems as the external preparation can be solved In particular, the object of the present invention is achieved by mixing nimesulide as an active ingredient m a dispersed state m a base component which comprises an oily substance, a nomonic surface active agent, a basic substance, water and/or an absorption enhancer. More particularly, 0 1 to 5% by weight of nimesulide as an activ . ingredient in a form of fine particles is dispersed and - 4 - _ I INTELLECTUAL PROPERTY OFFICE | OF NZ I 2 k SEP 1998 I DCPCn/trn > , i ' f * W L J ' mixed in Che base component which further comprises a hydrophilic polymer or a white petrolatum to prepare an external preparation such as cream or ointment Nimesulide as an active ingredient may be used in any form as long as it can be made into a dispersed state m a base component In view of the easiness in grinding of the particles to be dispersed and the cost, the mean particle diameter of nimesulide is 0 01 |im or more On the other hand, in view of the transdermal absorbability and feeling on application (rough feeling) , it is 75 (im or less, i e the particle sizes that pass through a 200-mesh sieve, and more preferably from 0.5 to 50 }im, and further preferably from 1 to 30 Jim.

The antiinflammatory agent for external (topical) use of the present invention may be prepared as follows. For example, the cream agent is prepared by mixing and stirring an oil phase of heat-melted oil components and an aqueous phase in which water-soluble components have been dissolved; adding nimesulide in a form of fine particles, and further carrying out stirring and cooling The ointment is prepared by adding nimesulide m a form or fine particles into the heat-melted oil components with stirring and cooling, and further carrying out stirring and cooling.

The pH of the pharmaceutical preparation may - 5 - ! INTELLECTU^fibpaTr6FF/CE OF NZ 19 JUL 1999 desirably be controlled from 4 to 8, more preferably from 5 to 7, m view of the skin irritation and the transdermal aos orbabi1ity Examples of the base to prepare the antiinflammatory agent for external use of the present invention include a so-called gel cream comprising a hydrophilic polymer, an oily substance, a nonionic surface active agent, a basic substance, and water, a vanishing cream produced from a higher alcohol, a hydrocarbon, a fatty acid ester, a polyhydric alcohol, a base, an antiseptic, water, and the like, a hydrophilic ointment or an absorptive ointment cream t i according to The Japanese Pharmacopeia produced from a white petrolatum, a surface active agent, a higher alcohol, a hydrocarbon, a fatty acid ester, a polyhydric alcohol, an antiseptic, water, an'3 the like, and the FAPG base comprising a higher alcohol, polyhydric alcohol, and the like. As the prescription for the cream agent, a pharmaceutical preparation obtained by mixing 0.1 to 5% by weight of nimesulide in a so-called gel cream base comprising 0 2 to 3% by weight of a hydrophilic polymer, 2 to 20% by weight of an oily substance, 0.5 to 7% by weight of a nonionic surface active agent, 0 01 to 5% by weight of a basic substance, and 50 to 90% by weight of water is the most preferable from the viewpoint of the transdermal absorption As the prescription for the ointment INTELLECTUAL PROPERTY OFFICE OF NZ 2 h SEP 1938 preparation, a pharmaceutical preparation obtained by mixing 0 1 to 5% by weight of nimesulide in a petrolatum ointment comprising 35 to 80% by weight of a white petrolatum, 2 to 2 0% by weight of an oily substance, and 0.5 to 7% by weight of a nonionic surface active agent is the most preferable Then, the base components of the present invention are described m further detail Examples of the hydrophilic polymer include carboxyvmyl polymers (CARBOPOL 940, 941 manufactured by B.F Goodrich Chemical Co., HIBISWAKO 104, 105, manufactured by Wako Pure Chemical Industries, Ltd., and the like), hydroxypropylcellulose (HPC-L, HPC-M manufactured by Nippon Soda Co , Ltd., and the like), polyoxyethylenepolyoxypropylene block polymer (Lutrol F68 manufactured by BASF Co., and the like) These hydrophilic polymers may be used alone or as a mixture of two or more and mixed preferably m an amount of from 0 2 to 3% by weight, more preferably, from 0.5 to 2% by weight in view of the viscosity and stickiness of the cream Examples of the oily substance include fatty acid esters such as diisopropyl adipate, diisopropyl sebacate, diethyl sebacate, medium chain fatty acid triglycerides, medium chain fatty acid propylene glycols, isopropyl myristate, and the like, fatty acids such as stearic acid, oleic acid, myristic acid, and the like; higher alcohols ? 9 JUL 1999 I such as cetanol, stearyl alcohol, cetostearyl alcohol, oleyl alcohol, behenyl alcohol, and the like, hydrocarbons such as white petrolatum, liquid paraffin, scualane, and the like; plant oils and fats such as olive oil, hohoba oil, castor oil, and the like, and other oily substances such as crotamiton, benzyl alcohol, and the like In the case of t the cream preparation, the oily substance is mixed in an amount of from 2 to 20% by weight, preferably from 5 to 15% by weight, m view of the spreadability of cream, transdermal absorption, stickiness, shining, and instability m production of preparations (e.g., liquid separation), and I i the like In the case of the ointment preparation, it is mixed m an amount of from 2 to 20% by weight, preferably from 3 to 7% by weight.

Examples of the surface active agent include sorbitan fatty acid esters such as sorbitan monostearate, sorbitan sesquistearate, and the like, glycerol fatty acid esters such as glyceryl monostearate, diglyceryl monooleate, and the like, polyoxyethylenesorbitan fatty acid esters such as polyoxyethylene(20)sorbitan monostearate, polyoxyethylene (20) sorbitan monooleate, and the like, polyethylene glycol fatty acid esters such as polyoxyethylene (10) monostearate, polyoxyethylene(10) monolaurate, and the like, polyoxyethylene alkyl ethers such as polyoxyethylene(9) lauryl ether, polyoxyethylene(23) INTELLECTUAL PROPERTY OFFICE OF NZ 2 <i SEP 1998 cetyl ether, and the like, polyoxyethylene alkylphenyl ethers such as polyoxyethylene(10) nonylphenyl ether, polyoxyethylene(10) octylphenyl ether, and the like, and polyoxyethylene hydrogenated castor oil such as polyoxyethylene(10) hydrogenated castor oil, polyoxyethylene(60) hydrogenated castor oil, and the like These surface active agents may be used alone or as a mixture of two or more and mixed in an amount of from 0.5 to 7% by weight, preferably, from 1 to 5% by weight Examples of the basic substance include inorganic or organic bases such as potassium hydroxide, sodium hydroxide, tnethanolamine, diisopropanolamine, monoethanolamine, and the like, and organic bases are preferable from the viewpoint of the transdermal absorption These basic substance may be mixed in an amount of from 0.01 to 5% by weight, preferably from 0.1 to 2% by weight.

In addition, in order to enhance the transdermal absorption of nimesulide, the absorption enhancer may be mixed in the above-described pharmaceutical preparation depending on the type of the pharmaceutical prescription. Examples of the absorption enhancer include organic bases, crotamiton, medium chain fatty acid esters, 1-menthol, benzyl alcohol, and the like. The organic base facilitates the release of nimesulide from the base since it makes nimesulide water-soluble by forming a salt with nimesulide.

Examples of the organic base include dusopropanolamine, meglumine, triethanolamine, and 1— (2 — hydroxy ethyl) pyrrolidine, and dusopropanolamine and l-(2- hydroxyetnyl)pyrrolidine are the most preferable The absorption enhancer is mixed m an ->jat of from 0 1 to 20% by weight, preferably from 0 2 to 10% by weight, alone or as a mixture of two or more The above-described basic substance and the organic base as an absorption enhancer act also as a pH controlling agent of the preparation That is, when pH of the pharmaceutical preparation is too low (eg, 3 or less) , the J high acidity makes skin irritation strong When pH is too high (e.g., 9 or more), the transdermal absorbability of the medical agent is reduced, skin irritation becomes strong, and the pharmaceutical preparation colors yellow.

Accordingly, the pH of the pharmaceutical preparation is controlled preferably in the range of from 4 to 8 by the amount of the above-described basic substance or the absorption enhancer to be mixed In addition to the above-described components, animal oils and fats, waxes, hydrocarbons, antiseptics, wetting agents, and the like may be added and mixed.

Examples of the animal oil and fat include beef tallow, pork tallow, horse oil, and the like. Examples of the wax include microcrystalline wax, montan wax, bees wax, and the INTELLECTUAL PROPERTY OFFICE OF NZ 2 "i SEP 1998 like. Examples of the hydrocarbon include paraffin, ceresine, and the like. Examples of the antiseptic include methylparaben, propylparaben, butylparaben, and the like. Examples of the wetting agent include polyhydric alcohols such as glycerol, 1,3-butylene glycol, propylene glycol, dipropylene glycol, and the like These additives may be I the mixed m amounts generally employed for cream and ointment preparations The present invention is illustrated m greater detail with reference to the following Examples.

Example 1 Component % by weight (1) Nimesulide (Particle Diameter 5 to 20 jim) 3 (2) Carboxyvmyl Polymer 1 (3) Diisopropyl Sebacate (4) Isopropyl Myristate (5) Crotamiton 3 (6) Polyoxyethylene (20) sorbitan Monostearate (7) Me thy lparaben 0.1 (8) Propylparaben 0.1 (9) Diisopropanolamine 0.5 (10) Purified Water 72 3 100 0 The components (3), (4), (5), (6), and (8) were melted by heating at 75°C A solution which had been separately prepared by dissolving the component (7) in about 90% of the component (10) at 75°C was added, and the mixture was INTELLECTUAL PROPERTY OFFICE 6F NZ 1 k SEP 1998 stirred to effect emulsification The component (2) was gradually added at 50°C and the mixture was thoroughly stirred Then, the component (1) was gradually added and dispersed by stirring Then, a solution which had been prepared by dissolving the component (9) m the remaining component (10) v-as added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide Example 2 ' Component % by weight (1) Nimesulide (Particle Diameter 20 to 4 0 ^m) 3 (2) Carboxyvinyl Polymer * 1 (3) Diisopropyl Sebacate (4) Isopropyl Myristate (5) Crotamiton 3 (6) Polyoxyethylene(20)sorbitan Monostearate (7) Methylparaben 0.1 (8) Propylparaben 0.1 (9) Dusopropanolamine 0 5 (10) Purified Water 72.3 100.0 The components (3), (4), (5), (6), and (8) were melted by heating at 75°C. A solution which had been separately prepared by dissolving the component (7) in about 90% of the component (10) at 75°C was added, and the mixture was stirred to effect emulsification. The component (2) was gradually added at 50°C and the mixture was thoroughly stirred. Then, the component (1) was gradually added and INTELLECTUAL PROPERTY OFFICE OF NZ 2 'i SEP 1998 dispersed by stirring. Then, a solution which had been prepared by dissolving the component (9) m the remaining component (10) was added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide Example 3 Component % by weight (1) Nimesulide (Particle Diameter. 5 to 20 Jim) 3 (2) Carboxyvinyl Polymer 1 (3) Diethyl Sebacate (4) Middle-length Fatty Acid Triglyceride 8 (5) Crotamiton 3 (6) Polyoxyethylene(20)sorbitan Monostearate (7) Me thylparaben 0.1 (8) Propylparaben 0.1 (9) 1-(2-Hydroxyethyl)pyrrolidine 0.5 (10) Purified Water 74.3 100.0 The components (3), (4), (5), (6), and (8) were melted I by heating at 75°C. A solution which had been separately prepared by dissolving the component (7) in about 90% of the component (10) at 75°C was added, and the mixture was stirred to effect emulsification The component (2) was gradually added at 50°C and the mixture was thoroughly stirred Then, the component (1) was gradually added and dispersed by stirring Then, a solution which had been prepared by dissolving the component (9) m the remaining component (10) was added, and the mixture was stirred until ^ INTELLECTUAL PROPER QfNUt OF NZ 2 h SEP 1998 orr Fi\/pn U ' the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide Example 4 Component % by weight (1) Nimesulide (Particle Diameter- 5 to 20 ^Lm) (2) Carboxyvinyl Polymer 1 (3) Diethyl Sebacate (4) Middle-length Fatty Acid Triglyceride 8 (5) Crotamiton 3 (6) Polyoxyethylene(20)sorbitan Monostearate (7) Methylparaben 0.1 (8) Propylparaben 0.1 (9) 1-(2-Hydroxyethyl)pyrrolidine 0 5 (10) Purified Water 72.3 J 100.0 The components (3), (4), (5), (6), and (8) were melted by heating at 75°C. A solution which had been separately prepared by dissolving the component (7) m about 90% of the component (10) at 75°C was added, and the mixture was stirred to effect emulsification. The component (2) was gradually added at 50°C and the mixture was thoroughly stirred. Then, the component (1) was gradually added and dispersed by stirring Then, a solution which had been prepared by dissolving the component (9) in the remaining component (10) was added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide.

INTELLECTUAL PROPERTY OFFICE OF NZ 2 4 SEP 1938 RECEIVFD Example 5 Cc orient % by weight (1) Nimesulide (Particle Diameter 0 5 to 10 Jim) (2) Carboxyvinyl Polymer (3) Diisopropyl Adipate (4) Isopropyl Myristate (5) 1-Menthol (6) Polyoxyethylene(20)sorbitan Monostearate 3 1 5 2 5 I (7) Methylparaben (8) Propylparaben (9) Dusopropanolamine (10) Purified Water 0 1 0.1 0.5 73 3 100.0 The components (3), (4), (5), (6), and (8) were melted by heating at 75°C A solution which had been separately prepared by dissolving the component (7) m about 90% of the component (10) at 75°C was added, and the mixture was stirred to effect emulsification The component (2) was gradually added at 50°C and the mixture was thoroughly stirred Then, the component (1) was gradually added and dispersed by stirring. Then, a solution which had been prepared by dissolving the component (9) m the remaining component (10) was added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide INTELLECTUAL PROPERTY OFFICE OF NZ 2 k SEP 1998 RECEIVED Example 6 Component % by weight (1) Nimesulide (Particle Diameter 0 5 Co 10 jim) (2) Stearic Acid (3) Diisopropyl Adipate (4) CeCanol (5) Middle-length Fatcy Acid Triglyceride (6) Polyoxyethylene(23) Cecyl Ether 3 5 7 3 1 5 1 0.5 * (7) Sorbitan Monostearate (8) 1,3-BuCylene Glycol (9) Dusopropanolamine (10) Sodium Benzoate (11) Purified Water 0.1 69 4 100 0 The components (2), (3), (4), (5), (6), and (7) were melted by heating at 75°C. A solution which had been separately prepared by dissolving the components (8) , (9) , and (10) in the component (11) at 75°C was added, and the \ mixture was stirred to effect emulsification The component (1) was gradually added at 50°C or lower, and the mixture was stirred until the mixture became homogenous to obtam an antiinflammatory cream preparation containing nimesulide. - 16 INTELLECTUAL PROPERTY OFFICE OF NZ 2 4 SEP 1998 Example 7 Component % by weight (1) Nimesulide (Particle Diameter 0 5 to 10 }im) 3 (2) Crotamiton 3 (3) Diethyl Sebacate 5 (4) Microcrystallme Wax 10 (5) Middle-length Fatty Acid Triglyceride 7 (6) Propylene Glycol Fatty Acid Ester 10 (7) Behenyl Alcohol 4 (8) Dusopropanolamine 0 2 (9) Dipropylene glycol 7 (10) Propylene Glycol Monostearate 7 (11) White Petrolatum 43.8 100.0 The components (2), (3), (4), (5), (6), (7), (8), (9), (10), and (11) were melted by heating at 80°C. The component (1) was gradually added at 50°C and dispersed by stirring to obtain an antiinflammatory ointment preparation containing nimesulide.

Example 8 (A dispersed-type cream preparation in which the active ingredient has the particle diameter of 7 6 to 180 Jim) Component % by weight (1) Nimesulide (Particle Diameter 75 to 180 Jim) 3 (2) Carboxyvinyl Polymer 1 (3) Isopropyl Myristate 15 j(4) Polyoxyethylene(20)sorbitan Monostearate 5 (5) Methylparaben 0 1 (6) Propylparaben 0 1 (7) Propylene Glycol 3 (8) Diethanolamine 0 5 (9) Purified Water 72 3 100.0 The components (3), (4) j and (6) were melted by heating at 75°C. A solution which had been separately prepared by dissolving the component (6) and (7) m about 90% of the component (9) at 75°C was added, and the mixture was stirred to effect emulsification. The component (2) was gradually added at 50°C and the mixture was thoroughly stirred. Then, the component (1) was gradually added and dispersed by stirring. Then, a solution which had been prepared by dissolving the component (8) in the remaining component (9) was added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide.

Reference Example (A cream preparation m which the active ingredient is dissolved) Component % by weight (1) Nimesulide (2) Carboxyvinyl Polymer (3) Isopropyl Myristate (4) Polyoxyethylene(2 0)sorbitan Monostearate (5) Methylparaben (6) Propylparaben (7) 1,3-Butylene Glycol (8) Diethanolamine (9) Purified Water 3 1 15 5 0 1 0.1 3 6 66.8 100.0 The components (3) , (4) , and (6) were melted by heating at 75°C A solution which had been separately prepared by dissolving the components (5) and (7) m about 90% of the component (9) at 75°C was added, and the mixture was stirred to effect emulsp-fication. The component (2) was gradually added at 50°C and the mixture was thoroughly stirred to dissolve the component (2) Then, the component (1) was gradually added and mixed by stirring. Then, a solution which had been prepared by dissolving the component (8) m the remaining component (9) was added, and the mixture was stirred until the mixture became homogenous to obtain an antiinflammatory cream preparation containing nimesulide.

INTELLECTUAL PROPERTY OFFICE OF NZ 19 2 "i SEP 1998 RECEIVED Test: Example 1. Suppression test of carrageenm-induced rat foot edema The antiinflammatory activity of the cream preparations of Examples 1, 2, 5, 7, and 8 and Reference Example as well as a commercially available lndomethacin-contaming cream preparation were examined based on the suppression of carrageenin-mduced rat foot edema.

Test Method The test substance was applied on a right foot sole of male Wister rats each weighing 132 to 150 g, and the right foot sole was fixed by covering with wrapping film. When the drug was applied, the animal was shackled with a plastic neck shackle and put into an individual cage m order to avoid oral ingestion of the drug. After 4 hours from the application of the drug, the drug was completely removed with absorbent cotton containing slightly warm water. Immediately, a physiological saline containing 1% carrageenm (0 1 ml) was subcutaneously injected at foot sole. After 3 hours, the foot volume was measured, and the edematization ratio was calculated based on the foot volume before injection of prophlogistic substance. The test results are shown in Table 1 - 20 intellectual property OFFICE OF NZ 2 4 SEP 1998 RECEIVED Table 1 J Sample (administered amount 100 mg/site) Number of animals Edematization ratio (%) (after 3 hours) Control 8 77.6 Cream preparation of Example 1 8 38 9 Cream preparation of Example 2 8 1 Cream preparation of Example 5 8 45.6 Cream preparation of Example 7 8 50 6 Cream preparation of Example 8 8 64 6 Cream preparation of Reference Example 8 53 .1 Commercially available mdomethacin cream preparation 8 68.6 From the results an Table 1, at is clear that the pharmaceutical preparations of Examples 1, 2, 5, 7, and 8 showed superior antiinflammatory effect in comparison with the commercially available mdomethacin cream preparation, which is equal or higher even m comparison with the cream preparation of Reference Example containing nimesulide in a dissolved state Test Example 2 Coloring test The cream preparations of the present invention and the cream preparation of the Reference Example were prepared and spread on a cotton cloth, and the degree of coloring was observed The test results are shown in Table 2 MhutUTUAl PHUHtHIY OFFICE OF HZ rr,LE 2 4 Slip jggs I

Claims (9)

Table 2 Sample Appearance at tne time of preparation Coloring of cloth Cream preparation of Example 1 Slightly yellowish white cream Almost no coloring Cream preparation of Example 2 Slightly yellowish white cream Almost no coloring Cream preparation of Reference Example Yellow cream Colored yellow As is clear from Table 2, the cloth was colored in the case of the cream preparation of Reference Example containing nimesulide in a dissolved state but the cream preparations of Examples 1 and 2 according to the present invention showed almost no coloring Effect of the Invention The antiinflammatory agent for external use of the present invention m which nimesulide is mixed m a dispersed state has pharmacological effects equal to or higher than those of the dissolved-type preparation, has no skin irritation, is safe, and does not soil the skin and clothes since it is not colored. Accordingly, the present invention is extremely useful as an agent m the field of dermatology for treating eczema, dermatitis, and the like, and as an antiinflammatory external preparation in the field of orthosis for treating chronic articular rheumatism, osteoarthritis, shoulder joint periarthritis, peritendinitis, myalgia, and tumentia and pain after injury - 22 INTELLECTUAL PROPERTY OFFICE OF NZ 2« »;EP I99S ' ' CLAIMS

1 An antiinflammatory agent for topical application comprising nimesulide as an active ingredient m the form of fine particles of mean diameter 0 01 to 75 jim and a base component, wherein said nimesulide is mixed in a dispersed state in said base component

2 The antiinflammatory agent for topical application as claimed in claim 1, wherein nimesulide is mixed in an amount of from 0 1 to 5% by weight

3 The antiinflammatory agent for topical application as claimed in claim 1, which has pH of from 4 to 8.

4 The antiinflammatory agent for topical application as claimed m claim 1, wherein said base component comprises a hydrophilic polymer, a white petrolatum, an oily substance, a nonionic surface active agent, water, a basic substance and/or an absorption enhancer

5 . The antiinflammatory agent for topical application as claimed in claim 4, wherein said absorption enhancer is an organic base, crotamiton, a medium chain fatty acid estei; 2-menthol, and/or benzyl alcohol.

6 . The antiinflammatory agent for topical application as claimed m claim 5, wherein said organic base is dusopropanolamine, meglumine, triethanolamme, and/or l-(2-hydroxyethyl) pyrrolidine

7 . The antiinflammatory agent for topical application as claimed in any of claims 1 to 6, wherein the dosage form is a cream preparation

8. The antiinflammatory agent for topical application as - 23 - »7 O " ' claimed in claim 7, wherein nimesulide in an amount of 0 1 to 5% by weight is mixed in a gel-like cream base comprising a hydrophilic polymer in an amount of from 0 2 to 3% by weight, an oily substance in an amount of from 2 to 20% by weight, a nonionic surface active agent in an amount of from 0.5 to 7% by weight, a basic substance m an amount of from 0.01 to 5% by weight, and water in an amount of from 50 to 90% by weight.

9 . The antiinflammatory agent for topical application as claimed in any of claims 1 to 7, wherein the dosage form is an ointment preparation. 10 The antiinflammatory agent for topical application as claimed m claim 9, wherein nimesulide in an amount of 0.1 to 5% by weight is mixed in a petrolatum ointment base component comprising a white petrolatum in an amount of from 35 to 80% by weight, an oily substance m an amount of from 2 to 20% by weight, and a nonionic surface active agent in an amount of from 0.5 to 7% by weight. 11 A process for producing an antiinflammatory agent for external use, which comprises gradually adding nimesulide as an active ingredient m a form of fine particles of mean diameter 0 01 |im to 75 |im, into a base component, and dispersing nimesulide by stirring. 12 The process as claimed in claim 11, wherein an oil component melted by heating is used as the base component 13 The process as claimed in claim 11, wherein an oil phase of heat-melted oil components and an aqueous ~y 11< ' ' phase in which water-soluble components have been dissolved are mixed by stirring and used a base component 14 An antiinflammatory agent as defined in claim 1 for external use compnsing nimesulide as an active ingredient and a base component, substantially as herein described with reference to any example thereof end of claims - 2S - OF HZ 2 9 JUL 1999