Manufacture of pellets of xanthine derivatives

US5160469A · kind A · utility

Assignee

• Nordmark Arzneimittel GmbH · DE

Inventors

• Thomas Moest · Moorrege, DE
• Claus H. Pich · Moorrege, DE

Key dates

• Filing date: Sep 7, 1990
• Grant date: Nov 3, 1992
• Expiry date: Sep 7, 2010

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61K31/52
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

A process for the manufacture of pellets which are composed of xanthine derivatives and are predominantly spherical, have a particle size in the range of 0.3 to 4 mm and have a bulk density above 0.5 g/cm.sup.3 by reacting the appropriate xanthine derivative with water or a water/alcohol mixture, entails anhydrous powdered xanthine derivative with an average particle size of from 20 to 200 .mu.m being suspended by stirring at from 40.degree. to 70.degree. C. in a nonsolvent which is immiscible with water and has a boiling point in the range from 60.degree. to 160.degree. C., then adding from 10 to 40% by weight, based on the anhydrous xanthine derivative, of water or a water/alcohol mixture and subsequently allowing to cool to room temperature at from 5.degree. to 20.degree. C. per hour, it being possible to reduce the stirring speed after agglomeration to about 1/3 to 2/3 of the original, and the pellets being separated from the liquid and dried, the pellets being used, possibly with a delayed release coating, as active compound in a drug.