Implant devices for intravesical administration and local drug delivery. The device has a body which includes a hollow tube formed of a biocompatible material; at least one reservoir in the tube which contains a drug; and one or more apertures through which the drug can be released. The device is configured for minimally invasive insertion into a body cavity, such as the bladder. The hollow tube may be elastomeric to permit the device to be elastically deformed from its initial shape into an elongated shape for passage through a catheter, where following such passage the device can return to or toward its initial shape to facilitate retention of the device in the body cavity. The body may have a narrow, elongated shape effective to permit insertion of the drug delivery device through a catheter without necessarily deforming the body, yet include flexible projections which effect retention within the body cavity.