Patent ID: 7438701

Claim:
A method for delivery of an agent to a delivery site in a subject, the method comprising the steps of: (a) implanting at the delivery site at least a distal portion of a device, the device comprising: an elongate body comprising a proximal end defining an inlet, and a distal end defining an outlet, the elongate body defining a lumen in the elongate body, said lumen extending between the proximal and distal ends; and a diffuser element operatively associated with the elongate body so as to define a diffusion space, wherein the elongate body distal end outlet is disposed in and in fluid communication with the diffusion space, wherein the diffuser element is drug-permeable and water-permeable so as to provide for dilution of a drug in the diffusion space and movement of drug out of the device; and (b) introducing into the elongate body inlet a drug at a first concentration, wherein said drug moves through the elongate body lumen, out the elongate body outlet, and into the diffusion space, and further wherein water from the environment outside the device passes into the diffusion space through the diffuser element to dilute drug in the diffusion space to a second concentration, and wherein said diluted drug diffuses out through the diffuser element to exit the device at the delivery site in the subject.