| PATENT NUMBER | This data is not available for free |
| PATENT GRANT DATE | July 29, 1986 |
| PATENT TITLE |
Compounds having antiinflammatory activity, obtained by complexation of piroxican with .beta.-cyclodextrin, and pharmaceutical compositions containing them |
| PATENT ABSTRACT | New inclusion compounds of 4-hydroxy-2-methyl-N-2-pyridyl-2H-1,2-benzothiazine-3-carboxyamide-1,1-dio xide with .alpha., .beta. or .gamma. cyclodextrins, obtained by reaction of said cyclodextrins and said 4-hydroxy-2-methyl-N-2-pyridyl-2H-1,2-benzothiazine-3-carboxyamide-1,1-dio xide in aqueous or water/organic solutions are described. The ratio between 4-hydroxy-2-methyl-N-2-pyridyl-2H-1,2-benzothiazine-1,1-dioxide and the cyclodextrins is comprised between 1:10 and 1:1; preferably, it is about 1:2.5. The compounds of the invention possess high antiinflammatory and analgesic activities, together with a considerably reduced gastrolesive action |
| PATENT INVENTORS | This data is not available for free |
| PATENT ASSIGNEE | This data is not available for free |
| PATENT FILE DATE | November 13, 1984 |
| PATENT FOREIGN APPLICATION PRIORITY DATA | This data is not available for free |
| PATENT CLAIMS |
We claim: 1. The inclusion complex of piroxicam with .alpha.,.beta.- or .gamma. cyclodextrin, in the ratio between 1:1 and 1:10 of piroxicam and said cyclodextrin respectively. 2. The inclusion complex according to claim 1, wherein the piroxicam/cyclodextrin ratio is 1:2.5. 3. The inclusion complex according to claim 1, wherein the cyclodextrin is .beta.-cyclodextrin. 4. A pharmaceutical composition useful as an analgesic, in unit dosage form comprising an effective amount of the inclusion complex of piroxicam and beta-cyclodextrin wherein said piroxicam and said cyclodextrin are in the ratio between 1:1 and 1:10 respectively and at least one pharmaceutically acceptable carrier. 5. A pharmaceutical composition according to claim 4 in the form of tablets, compresses, sachets, suppositories, suited for oral or rectal administration, containing from 10 to 50 mgs of said inclusion complex per unit dosage. 6. A pharmaceutical composition having antiinflammatory activity for oral or rectal administration, in the form of tablets, capsules, sachets or suppositories containing an effective amount of an inclusion complex of piroxicam and beta-cyclodextrin wherein said piroxicam and said cyclodextrin are in the ratio between 1:1 and 1:10 respectively and at least one pharmaceutically acceptable carrier. 7. A pharmaceutical composition according to claim 6, containing from 10 to 50 mg of said inclusion complex per unit dosage. -------------------------------------------------------------------------------- |
| PATENT DESCRIPTION |
The present invention refers to new compounds obtained by complexation of 4-hydroxy-2-methyl-N-2-pyridyl-2H-1,2-benzothiazine-3-carboxamide-1,1-diox ide (hereinafter referred to as piroxicam) with .alpha.-, .beta.- or .gamma.-type cyclodextrins. Piroxicam is a compound belonging to the class of the Non Steroidal AntiInflammatory drugs (NSAI) which, thanks to its remarkable analgesic and antiphlogistic activity, is effectively employed in the treatment of arthro-rheumatic diseases. On the other hand, piroxicam is responsible of lesive effects on the gastrointestinal mucosa, though at a lower extent with respect to other drugs of the same therapeutical class widely employed in the clinical praxis. In addition, piroxicam is practically insoluble in water, and this may represent a limiting factor for an optimal employment of the substance. It has now been found, and this is the object of the present invention, that piroxicam can advantageously be complexed by inclusion into .alpha.-, .beta.- or .gamma.-type cyclodextrins. The cyclodextrins are natural cyclic compounds consisting of 6(.alpha.), 7(.beta.) or 8(.gamma.) (1.fwdarw.4) D-glucopyranosidic units. The so obtained complex possesses a high solubility, is rapidly absorbed and is better tolerated. In this complex, piroxicam and the cyclodextrins may be present in ratios comprised between 1:1 and 1:10, preferably 1:2.5. The preparation of the compound can be carried out in different ways: (a) piroxicam is directly dissolved in an aqueous solution of the selected cyclodextrin, from which the complex separates by crystallization; (b) piroxicam is dissolved in an organic medium, the organic solution is mixed under stirring with an aqueous solution of the selected cyclodextrin, and the obtained complex is finally separated by crystallization; (c) the compounds are dissolved under stirring in a water/ammonia solution, and the complex is subsequently separated by drying up; (d) the compounds are dissolved under stirring in a hot water/ammonia solution, and the complex is subsequently separated by freeze-drying or atomization in air stream. The compound obtained by this last procedure seems to display more favorable biological properties |
| PATENT EXAMPLES | available on request |
| PATENT PHOTOCOPY | available on request |
|
Want more information ? Interested in the hidden information ? Click here and do your request. |