Drive assembly for a drug delivery device and drug delivery device Drive assembly for a drug delivery device (100), comprising a housing (10) with a proximal end (11) and a distal end (12), a drive member (40), and a piston rod (50). A longitudinal axis (A) extends between the proximal end (11) and the distal end (12). The piston rod (50) is axially moveable relative to the housing (10). The piston rod (50) comprises a guide track (53). The drive member (40) comprises a guide piece (45) being disposed and being movable in the guide track (53). The guide track (53) comprises at least one section (54) which is oblique relative to the longitudinal axis (A) and defining a displacement for dispensing a single pre-set dose of medication during a relative movement between the guide piece (45) and the piston rod (50) when the guide piece (45) cooperates with the oblique section (54) between a distal final area (56) of the oblique section (54) and a proximal final area (58) of the oblique section (54). The pitch of the at least one oblique section (54) decreases from the distal final area (56) to the proximal final area (58). Drug delivery device (100) with a drive assembly, wherein a medication containing cartridge (102) is coupled to the piston rod (50) in a manner to dispense the medication (103).La présente invention concerne un ensemble entraînement pour dispositif dadministration de médicament, et un dispositif dadministration de médicament. Ledit ensemble entraînement pour dispositif dadministration de médicament (100) comprend un boîtier (10) pourvu dune extrémité proximale (11) et dune extrémité distale (12), un élément dentraînement (40), et une tige de piston (50). Un axe longitudinal (A) sétend entre lextrémité proximale (11) et lextrémité distale (12). La tige de piston (50) est mobile axialement par rapport au boîtier (10). Ladite tige de piston (50) comprend une rampe (53). Lélément dentraînement (40) comprend une pièce de guidage (45) disposée, et mobile, dan
