EP0521310B1 — Solid dispersion tablets containing 1,4-dihydropyridine derivatives and process for the preparation thereof

USPTO Abstract

The present invention relates to a pharmaceutical solid dispersion tablet comprising a solid dispersion material (a) which comprises a substantially water-insoluble 1,4-dihydropyridine derivative as pharmaceutical active agent represented by the general formula [I]: <CHEM> wherein Ar is a substituted aryl or benzofurazanyl group, R<1> is a substituted or unsubstituted alkyl group, R<2> is a substituted or unsubstituted alkyl or alkenyl group or a substituted piperidyl group, R<3> and R<4> each independently represent a substituted or unsubstituted alkyl group, and the substituent R<1>OCO- at the 5-position may be replaced by a dialkylphosphonoate or alkylene dioxyphosphoryl group, or a pharmaceutically acceptable acid addition salt thereof and hydroxypropyl cellulose; and a solid dispersion material (b) which comprises said 1,4-dihydropyridine derivative or its pharmaceutically acceptable acid addition salt and hydroxypropyl methyl cellulose phthalate. The present invention also relates to a process for preparing the above solid dispersion tablets.