Claims for Patent: 4,927,640

Summary for Patent: 4,927,640

Title:	Controlled release beads having glass or silicon dioxide core
Abstract:	Controlled release preparation containing a number of insoluble beads applied with one or more pharmaceutically active compounds, a method for the production thereof and the use in a treatment where a controlled release of a pharmaceutically active compound is needed.
Inventor(s):	Dahlinder; Lars-Erik D. (Molndal, SE), Johansson; Mats O. (Goteborg, SE), Sandberg; John A. (Molndal, SE), Sjo (Monlycke, SE)
Assignee:	Aktiebolaget Hassle (Molndal, SE)
Application Number:	06/907,599
Patent Claims:	1. Controlled release beads, each comprising a compact inert core selected from the group consisting of glass and silicon dioxide which is insoluble in water, physiological fluids and liquids commonly used for intraveneous infusion; a layer applied to the surface of the insoluble core consisting essentially of one or more pharmaceutically active compounds selected from among those compounds for which a non-instant drug release is wanted; and a release controllling polymeric membrane covering the active layer. 2. Beads according to claim 1, wherein the core has a size of 0.1-2 mm and the combination of the core and the active layer has a size of 0.2-3.0 mm. 3. Beads according to claim 2, wherein the core has a size of 0.1-0.50 mm and the combination of the core and the active layer has a size of 0.3-1.0 mm. 4. Beads according to claim 1, wherein the core comprises is silicon dioxide. 5. Beads according to claim 1, wherein the core comprises small particles of glass. 6. Process for the preparation of beads for use in controlled release products consisting essentially of (a) dissolving a pharmaceutically active compound in a solvent; (b) applying the dissolved active compound to an insoluble core selected from the group consisting of glass and silicon dioxide having a size of 0.1 to 2.0 mm; (c) drying the insoluble cores to remove the solvent and form beads having a coating of active compound and a size of 0.2 to 3.0 mm; and (d) further coating the beads with a release controlling polymeric membrane. 7. Beads according to claim 1, wherein the pharmaceutically active compound is to be administered orally or parenterally. 8. Beads according to claim 1, wherein the pharmaceutically active compound is used in the cardiovascular, gastrointestinal or chemotherapeutic field. 9. Beads according to claim 1, wherein the pharmaceutically active compound is a salt of an adrenergic beta-blocking agent. 10. Beads according to claim 1, wherein the pharmaceutically active compound is an antibiotic.