The present invention relates to a drug delivery device for dispensing a liquid medicament, comprising: a housing (12) having at least one feeder member (100), a disposable injector (60) comprising an injection needle (65), a flexible tube (64) and an injector fluid coupling (68), wherein the injection needle (65) is in fluid communication with the fluid coupling (68) via the flexible tube (64), a disposable cartridge (70) comprising a reservoir (80) at least partially filled with the liquid medicament and comprising a cartridge fluid coupling (90) in fluid communication with the reservoir (80), wherein the injector (60) and the cartridge (70) are releasably attachable to the housing (12) and arrestable to the housing (12) in an undeployed configuration (4), in which the injector fluid coupling (68) and the cartridge fluid coupling (90) are disconnected, and wherein one of injector (60) and cartridge (70) is displaceable relative to the other one of injector (60) and cartridge (70) from the undeployed configuration (4) into the deployed configuration (6) while attached to the housing (12), wherein when in deployed configuration the injector fluid coupling (68) and the cartridge fluid coupling (90) are in fluid communication.