Claims for Patent: 5,681,588

Summary for Patent: 5,681,588

Title:	Delayed release microtablet of .beta.-phenylpropiophenone derivatives
Abstract:	A cylindrical delayed release tablet with a convex or flat upper side and lower side is provided, along with a method for its production and a gelatin capsule containing 3-200 tablets of the same having identical or different release rates, wherein the tablet if made of .beta.-phenylpropiophenone derivatives of the formula I as active ingredient ##STR1## where R is n-propyl or 1,1-dimethylpropyl, and their pharmacologically acceptable salts, wherein the tablet has a height and diameter that are both, independently of one another, 1-3 mm, the active ingredient content is in the range from 81-99.9% of the weight of the microtablet, (but not taking into account the weight of any coating which is present, the active ingredient density is greater than 1, the release of active ingredient in the USP paddle method at 50 rpm is 80% as a maximum after 3 hours and as a minimum after 24 hours, the release rate is virtually independent of the pressure when compressing the tablets, and the tablet contains no release-delaying ancillary substance but can contain 0.1-5% by weight of a lubricant and 0-18.9% by weight of other conventional ancillary substances.
Inventor(s):	Kolter; Karl (Limburgerhof, DE), Fricke; Helmut (Mutterstadt, DE), Buehler; Volker (Karlsruhe, DE), Mueller-Peltzer; Herbert (Heidelberg, DE)
Assignee:	Knoll Aktiengesellschaft (Ludwigshafen, DE)
Application Number:	08/525,749
Patent Claims:	1. A cylindrical delayed release microtablet with a convex or flat upper side and lower side of .beta.-phenylpropiophenone derivatives of the formula I as active ingredient ##STR2## where R is n-propyl or 1,1-dimethylpropyl, and their pharmacologically acceptable salts, wherein a) the height and diameter are, independently of one another, 1-3 mm, b) the active ingredient content is in the range from 81 to 99.9% of the weight of the microtablet, c) the active ingredient density is greater than 1, d) the release of active ingredient in the USP paddle method at 50 rpm is 80% as a maximum after 3 hours and as a minimum after 24 hours, e) the release rate is virtually independent of the pressure when compressing the tablets, and f) the tablet contains no release-delaying ancillary substance but 0.1-5% by weight of a lubricant and 0-18.9% by weight of other conventional ancillary substances. 2. A tablet as claimed in claim 1, which in vivo results in a pronounced plasma level plateau with a PTF<75% and whose bioavailability does not depend on the intake of food. 3. A tablet as claimed in claim 1, wherein the active ingredient is propafenone hydrochloride. 4. A tablet as claimed in claim 1, wherein the height and diameter are approximately the same. 5. A gelatin capsule which contains 3-200 tablets as claimed in claim 1 with identical or different release rates. 6. A process for producing cylindrical delayed release microtablets as claimed in claim 1, which comprises a homogeneous mixture of 81-99.9% by weight of the granulated active ingredient with a particle size below 1 mm, 0.1-5% by weight of a lubricant and 0-18.9% by weight of other conventional ancillary substances which do not delay release being compressed in a cylindrical mold with a height and diameter each of 1-3 mm and being removed from the mold.