A drive-control system for an injection device for delivering a settable dose of a pharmaceutical substance contained in a cartridge, the system comprising a tubular housing body having a longitudinal axis (A-A), a proximal end and a distal end connectable to the cartridge enclosure, the system further comprising a helical spring contained in the housing body and a piston rod extending along the longitudinal axis (A-A) and moveable towards said distal end and blocked in translation towards the proximal end, wherein the housing body further contains (i) a control sleeve on which the spring is mounted, the control sleeve being rotatable around the axis (A-A), and (ii) a setting sleeve translatable along the axis (A-A), wherein - the control sleeve is threadably connected at its distal end to the setting sleeve; - the setting sleeve is engaged with the internal wall of the housing body in a way preventing rotation of the setting sleeve in relation to the housing body, - the setting sleeve is engaged with the piston rod by at least one series of ratchet teeth (6.1) on the piston rod directed towards the proximal end of the housing body and at least one resilient pawl (11.3) on the setting sleeve engaging the ratchet teeth (6.1) of the piston rod, in a way enabling the translation of the setting sleeve towards the proximal end of the housing body and blocking the translation of the setting sleeve in the opposite direction in relation to the piston rod; - a blocking member is provided on the distal end of the housing body, the blocking member being engaged with the piston rod by the at least one series of ratchet teeth (6.1) and at least one resilient pawl (12.1) on the blocking member engaging the ratchet teeth (6.1) of the piston rod so as to block the translation of the piston rod 6 in the proximal direction, whereby - rotation of the control sleeve in a first direction causes compression of the spring and translation of the setting sleeve towards the proximal end of the housing body, and extension of the spring causes translation of the setting sleeve towards the distal end of the housing body, rotation of the control sleeve in a second direction and translation of the piston rod towards the outside of the housing body, - the control sleeve is threadably connected at its distal end to the setting sleeve; - the setting sleeve is engaged with the internal wall of the housing body in a way preventing rotation of the setting sleeve in relation to the housing body, - the setting sleeve is engaged with the piston rod by at least one series of ratchet teeth (6.1) on the piston rod directed towards the proximal end of the housing body and at least one resilient pawl (11.3) on the setting sleeve engaging the ratchet teeth (6.1) of the piston rod, in a way enabling the translation of the setting sleeve towards the proximal end of the housing body and blocking the translation of the setting sleeve in the opposite direction in relation to the piston rod; - a blocking member is provided on the distal end of the housing body, the blocking member being engaged with the piston rod by the at least one series of ratchet teeth (6.1) and at least one resilient pawl (12.1) on the blocking member engaging the ratchet teeth (6.1) of the piston rod so as to block the translation of the piston rod 6 in the proximal direction, whereby - rotation of the control sleeve in a first direction causes compression of the spring and translation of the setting sleeve towards the proximal end of the housing body, and extension of the spring causes translation of the setting sleeve towards the distal end of the housing body, rotation of the control sleeve in a second direction and translation of the piston rod towards the outside of the housing body,