Patent ID: 7488316

Claim:
An implantable medical device for the storage and controlled release of a drug formulation comprising: a body portion; at least one reservoir located in at least one surface of the body portion and having a plurality of discrete release openings; at least one drug formulation, which comprises at least one drug, disposed within the at least one reservoir; a release-modifying agent disposed within the at least one reservoir and/or within a second reservoir which is separate from the at least one reservoir in which the drug formulation is disposed, wherein the release-modifying agent is selected from the group consisting of a non-volatile, monoprotic organic acid; a non-volatile, polyprotic organic acid; a non-volatile, mono-functional base; and a non-volatile, poly-functional base; one or more reservoir caps closing off the plurality of discrete release openings of the at least one reservoir; at least one reservoir cap support between at least two of the release openings which extends over the at least one drug formulation, wherein said one or more reservoir caps are in part supported by the at least one reservoir cap support; and electrical circuits, a power source, and a controller for disintegrating said reservoir caps to permit release of the drug formulation from the at least one reservoir.