The present invention relates to a diclofenac sodium oral pharmaceutical containing diclofenac sodium, a nonionic surfactant, a cholic acid derivative as an absorption promoting agent, and a glycerin or a glycol.The oral pharmaceutical has a rapid-acting effect and a good internal absorption even under non-fasting condition. Further, the pharmaceutical can be processed in a hard capsule pharmaceutical by filling it in a hard capsule as such, and has an excellent internal absorption under non-fasting condition, similarly to suppositories.

Description of the Invention

TECHNICAL FIELD

The present invention relates to a rapid-acting diclofenac sodium oral pharmaceutical.

BACKGROUND ART

Diclofenac sodium (Monosodium 2-(2,6-dichloroanilino) phenyl acetate, C.sub.14H.sub.10C.sub.12NNaO.sub.2) is a nonsteroidal drug having analgesic, anti-inflammatory and anti-rheumatic effects which was developed by CIBA-GEIGY AG in Switzerland (now, Novartis Pharma AG) in 1965. This drug has a strong action and a low toxicity compared with indomethacin or the like, and therefore is widely subjected to current clinical use.

The commercially available diclofenac sodium pharmaceuticals include tablets, delayed-release pharmaceuticals and suppositories, etc. Among them, oral pharmaceuticals are formulated for rapid-acting effect. However, it is recommended to avoid taking them on an empty stomach as they have side effects such as stomach discomfort.

However, the absorption of diclofenac sodium oral pharmaceuticals is outstandingly effected on whether or not a meal has been eaten. When they are taken after eating, the initial absorption of diclofenac sodium is outstandingly reduced in the amount and delayed in the rate compared with the case where they are taken on an empty stomach, and in some cases, the maximum absorption is confirmed at several hours to ten and several hours after taking them, and also individual difference is large in the absorption thereof.

Therefore, in case where an rapid-acting effect and certainty are taken seriously, it is the present state that the pharmaceuticals are used in most cases in a form of suppository. However, there are many patients who are reluctant to use the suppositories, and therefore the suppositories can not be used as conveniently as oral pharmaceuticals. Consequently, today there is a strong request for diclofenac sodium oral pharmaceuticals having a rapid-acting effect and certainty similarly to the suppository even in case where it is taken on a non-empty stomach.

It has been already known that in order to increase an internal absorption of a pharmaceutical agent that is slightly soluble in water, the pharmaceutical agent is formulated with a surfactant to increase the solubility of the pharmaceutical agent to water.

As the prior document, Japanese Patent Laid-open No. Sho 63-277617 discloses a medicine composition for oral administration from which micelles are formed, comprising an nonsteroidal anti-inflammatory agent such as diclofenac, and a nonionic surfactant such as polyoxyethylated surfactant, sorbitan fatty acids or the like. In addition, the examples of this document describe a pharmaceutical comprising diclofenac acid and polyoxyethylated castor oil. However, this document does not describe at all the above-mentioned problem on the absorption of diclofenac sodium pharmaceutical under non-fasting condition nor means for solving the problem. Further, this document does not describe as surfactant cholic acid derivatives that are varieties of anionic surfactants.

In addition, Japanese Patent Laid-open No. Hei 8-507515 discloses a particle-suspension of colloidal solid particles in which a pharmaceutical agent being slightly soluble in water is captured with solid particles that are emulsified and stabilized by adding a lipid that is insoluble or slightly soluble in water at room temperature to nonionic surfactant and bile salts containing propylene glycol as dispersant, and this document discloses that the pharmaceutical agent includes diclofenac. However, this document has no concrete disclosure on diclofenac pharmaceuticals. Also, this document does not describe problems to be solved by the present invention nor means for solving the problems similarly to the above-mentioned Japanese Patent Laid-open No. Sho 63-277617.

As mentioned above, although it was known that diclofenac being slightly soluble in water is mixed with surfactants in order to increase solubility and dispersibility, it was not necessary to use surfactants for diclofenac sodium having a higher water-solubility, and therefore the mixing of surfactants has not been considered.

DISCLOSURE OF THE INVENTION

Under the above-mentioned circumstances, the present inventor earnestly investigated and repeatedly considered to make diclofenac sodium oral pharmaceuticals rapid-acting under non-fasting condition by producing pharmaceuticals comprising a variety of substances such as surfactants, absorption promoting agent, melting point modifiers, solubilizing agents and viscosity modifiers, etc. and by using them in a test of kinetics in rat blood under non-fasting condition and in a dissolution test. As the results, the inventor found that diclofenac sodium oral pharmaceuticals have an excellent absorption under non-fasting condition by mixing a nonionic surfactant, a cholic acid derivative represented by deoxycholic acid as absorption promoting agent, and a glycerin or a glycol as melting point modifier (used for lowering melting point) with diclofenac sodium. Consequently, the present invention was completed on the basis of the finding.

That is, the present invention provides a diclofenac sodium oral pharmaceutical characterized by containing diclofenac sodium, a nonionic surfactant, a cholic acid derivative as an absorption promoting agent, and a glycerin or a glycol.

In addition, the present invention provides a diclofenac sodium oral pharmaceutical, which is filled in a hard capsule.

The rapid-acting diclofenac sodium oral pharmaceutical of the present invention is in a liquid state in which mixed compositions are dissolved each other or in a solid state in which the mixed compositions in a liquid state are solidified, and is not in a state of a particle-suspension in which a pharmaceutical agent is captured with carrier solid particles that is disclosed in Japanese Patent Laid-open No. Hei 8-507515.

And, the pharmaceutical of the present invention can be processed in an oral pharmaceutical by filling it in a hard capsule as such. The material of this hard capsule is preferably hydroxypropylmethylcellulose (HPMC). The rapid-acting diclofenac sodium oral pharmaceutical of the present invention can be also filled in a soft capsule, processed in an oral liquid by dissolving it in water or the like, pulverized by mixing it with a pulverization agent, granulated or processed in tablets. Further, these pharmaceuticals can be combined with a delayed-release pharmaceutical.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, each component of the oral pharmaceutical to be mixed along with the active ingredient in the present invention, diclofenac sodium will be described in further detail.

The nonionic surfactant used for the diclofenac sodium oral pharmaceutical of the present invention is a surfactant having little toxicity in oral administration, and can be used in a combination of two or more. Examples of the nonionic surfactant include saturated polyglycolated glycerides, polyoxyethylene sorbitan fatty acid esters (polysorbates) and polyglycerin fatty acid esters, polyoxyethylene glycerin fatty acid ester deoxycholic acids, sucrose fatty acid esters, lecithin derivatives, propyleneglycol fatty acid esters, glycerin fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbit fatty acid esters, polyoxyethylene lanolin/lanolin alcohol/bees wax derivatives, polyoxyethylene castor oil/hardened castor oil, polyoxyethylene sterol/hydrogenated sterol polyethyleneglycol fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene phenyl ethers, polyoxyethylene alkyl phenyl formaldehyde condensation products, and polyoxyethylene polyoxypropylene glycol, and the like. Among them, nonionic surfactants having a relatively high HLB value (HLB=10 to 20) are preferable.

The cholic acids derivatives as the absorption promoting agent used for the diclofenac sodium oral pharmaceutical of the present invention includes for example lithocholic acid, deoxycholic acid, glycodeoxycholic acid, taurodeoxycholic acid, chenodeoxycholic acid, glycochenodeoxycholic acid, taurochenodeoxycholic acid, ursodeoxycholic acid, glycoursodeoxycholic acid, tauroursodeoxycholic acid, cholic acid, glycocholic acid, taurocholic acid, ursocholic acid, glycoursocholic acid, tauroursocholic acid and the salts thereof such as sodium salt or potassium salt, etc. These cholic acid derivatives may be used in a combination of two or more.

The melting point modifiers used for the diclofenac sodium oral pharmaceutical of the present invention includes for example glycerin, polyethyleneglycols, propyleneglycols or a combination of two or more selected from these compounds. These melting point modifiers are used also as solubilizing agents.

The formulating ratio of the pharmaceuticals is as follows. The nonionic surfactant can be added in an amount of 0.05 to 20 parts by weight, preferably 1 to 5 parts by weight based on 1 part by weight of diclofenac sodium. In addition, the absorption promoting agent and melting point modifier may be added in an appropriate amount according to need, preferably based on 1 part by weight of diclofenac sodium, the absorption promoting agent is added in an amount of 0.01 to 5 parts by weight, preferably 0.05 to 0.5 part by weight, and the melting point modifier is added in an amount of 0.1 to 10 parts by weight, preferably 1.0 to 5.0 parts by weight.

A preferable formulation example for the pharmaceutical of the present invention comprises diclofenac sodium, and saturated polyglycolated glyceride (for example Gelucire 44/14 (trade name) manufactured by Gattefosse in France) or polyoxyethylene sorbitan fatty acid ester (for example, NIKKOL TS-10 (trade name), Polysorbate 60, manufactured by Nikko Chemicals Co., Ltd.) as nonionic surfactant, deoxycholic acid as absorption promoting agent and propylene glycol as melting point modifier. More preferable formulation example for the pharmaceutical comprises diclofenac sodium, and deoxycholic acid, hexaglyceryl monolaurate (for example NIKKOL Hexaglyn 1-L (trade name), manufactured by Nikko Chemicals Co., Ltd.) and propylene glycol, preferably in a weight ratio of 1:0.1:3.5:1.8.

The diclofenac sodium oral pharmaceuticals were prepared by using the surfactants, absorption promoting agents and melting point modifiers as mentioned above. The pharmaceuticals showed the most excellent initial kinetics in rat blood (non-fasting) and a high dissolution rate in the first fluid of Disintegration Test specified in The Japanese Pharmacopoeia.

Further, the diclofenac sodium oral pharmaceuticals of the present invention may contain other solubilizing agents, viscosity modifiers and excipients which are commonly used for pharmaceuticals, if necessary.
 

Claim 1 of 8 Claims

1. An oral pharmaceutical comprising a diclofenac sodium, a nonionic surfactant, a cholic acid derivative as an absorption promoting agent, and a glycerin or a glycol, wherein the cholic acid derivative is selected from the group consisting of lithocholic acid, deoxycholic acid, glycodeoxycholic acid, taurodeoxycholic acid, chenodeoxycholic acid, glycochenodeoxycholic acid, taurochenodeoxycholic acid, ursodeoxycholic acid, glycoursodeoxycholic acid, tauroursodeoxycholic acid, cholic acid, glycocholic acid, taurocholic acid, ursocholic acid, glycoursocholic acid, tauroursocholic acid and the salts thereof, wherein the pharmaceutical is in a liquid state in which the diclofenac sodium, the nonionic surfactant, the cholic acid derivative, and the glycerin or the glycol are dissolved.

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