Implantable drug delivery devices, and kits and methods incorporating them are described. The devices may, for example, be configured for implantation into an ocular region of a subject. The drug delivery devices may comprise multiple, selectively-triggerable drug reservoirs for administration of sequential or concomitant drug regimens. Some variations of devices may comprise one or more reservoirs that may be triggered by an optical stimulus, e.g., light having a wavelength within a certain wavelength range. The devices, methods, and kits may be useful in the treatment chronic ocular conditions, such as age-related macular degeneration.