Described are implantable devices having reservoirs for the sustained release of therapeutic agents. The devices are configured to be at least partially implanted in an eye and include a retention structure and a penetrable element coupled to and extending within at least a portion of the proximal end region of the device. The device includes a porous drug release element is positioned in fluid communication with an outlet of the device and a reservoir having a volume configured to contain one or more therapeutic agents in fluid communication with the outlet through the porous drug release element. The device is at least partially inserted along an axis of insertion.