Disclosed is an alignment device (400) for coupling a liquid drug cartridge (100) with a longitudinal cartridge axis (Z) and a constricted neck portion (110) with a cap (115) and a piercable septum (120) distal from the neck portion (110), the septum (120) being perpendicular to the cartridge axis (Z), with an adapter (200), including an adapter cannula (210) with a longitudinal cannula axis (Z) to pierce the septum (120).The alignment device (400) includes a proximal cartridge engagement structure (410) for axial aligned engagement with a distal end section of cartridge body (105). The alignment device (400) further includes a distal adapter engagement structure (415) for axial aligned engagement with the adapter (200).Thereby, a coupling of the cartridge (100) with the adapter (200) is enabled via the alignment device (400), wherein the adapter (200) and the cartridge (100) are, during the coupling, aligned by the cartridge engagement structure (410) and the adapter engagement structure (415), respectively relative to each other such that the longitudinal cartridge axis (Z) and the longitudinal cannula axis (Z) form a common longitudinal axis.
