devices for the local delivery of microdose amounts of one or more active agents , alone or in combination , in one or more dosages , to selected tissue of a patient are described . the devices generally include multiple microwells arranged on or within a support structure . the microwells contain one or more active agents , alone or in combination , in one or more dosages and / or release pharmacokinetics . in an exemplary embodiment , the device has a cylindrical shape , having symmetrical wells on the outside of the device , each well containing one or more drugs , at one or more concentrations , sized to permit placement using a catheter , cannula , or stylet . optionally , the device has a guidewire , and fiber optics , sensors and / or interactive features such as remote accessibility to provide for in situ retrieval of information and modification of device release properties . in the most preferred embodiment , the fiber optics and / or sensors are individually accessible to discrete wells .