The invention relates to a drug delivery device (1) for dispensing a liquid drug through a needle (7) with a proximal and a distal needle tip (7.1, 7.2), comprising- a body (2, 12),- a needle holder (5, 15) holding the needle (7) relative to the body (2, 12),- a cartridge holder (3, 13) holding a cartridge (4) comprising the liquid drug sealed with a septum (4.1) on a distal end and with a movable stopper (4.2) on a proximal end, and- a cap (8, 18) adapted to cover at least the distal needle tip (7.2) of the needle (7), wherein the cartridge holder (3, 13) is movable relative to the body (2, 12) from a retracted position towards an advanced position, thereby piercing the proximal needle tip (7.1) through the septum (4.1),characterized in that the cap (8, 18) is releasably engaged with the cartridge holder (3, 13), wherein the cap (8, 18) is released from the cartridge holder (3, 13) in its advanced position.
