A drug delivery device is provided that includes a device body, a number of solid, compressed drug tablets, and a retention frame. The device body includes a drug reservoir lumen and a retention frame lumen. The number of solid, compressed drug tablets are positioned in the drug reservoir lumen, and the retention frame is positioned in the retention frame lumen. The drug tablets may be mini-tablets aligned in the drug reservoir lumen, with an interstice formed between any two adjacent drug tablets facilitating deformation of the device body. Systems and method are also provided for loading a drug delivery device. In one embodiment, the method includes positioning one or more solid drug units upstream of the drug delivery device; and driving the drug units into the drug delivery device with a flow of pressurized gas.