Patent ID: 6113938
Filing Date: 2000-09-05
Classification: A61K

Abstract:
A delivery system for controlled delivery of a beneficial agent at a predetermined delivery rate comprising:an implantable capsule having an opening;a beneficial agent reservoir within the capsule for containing the beneficial agent;a membrane plug received in the opening of the capsule and providing a fluid permeable barrier between an interior and an exterior of the capsule, the membrane plug having a plurality of external ribs for engaging an interior surface of the capsule; anda clearance between exterior surfaces of the membrane plug and the interior surfaces of the capsule, wherein the predetermined delivery rate at which the beneficial agent is delivered from the reservoir is achieved by selecting the clearance, wherein the clearance is a difference between an exterior diameter of the external ribs and an interior diameter of the capsule, and the external ribs are between about -1% and about 8% larger than an interior diameter of grooves in the capsule.