Drug Delivery Device with End-Of-Dose Detection

A drug delivery device, comprising:

• a syringe comprising a barrel having a proximal end, a distal end having a cooperating surface, a needle arranged at the distal end, and a sidewall arranged between the proximal end and the distal end defining an interior configured to hold a composition;
• a plunger rod received at least partially within the interior of the syringe, the plunger rod comprising a proximal end, a distal end, and a stopper arranged at the distal end;
• a displaceable needle shield;
• a spring having a compressed configuration and an expanded configuration, the spring configured to displace the needle shield from a first, proximal position in which the displaceable needle shield does not surround the needle of the syringe to a second, distal position in which the displaceable needle shield at least partially surrounds the needle of the syringe;
• and
• a reusable sensor assembly coupled to the needle shield, the reusable sensor assembly comprising:
• a housing defining an interior, the housing having at least one opening therein and being coupleable to a drug delivery device;
• a mechanical switch received at least partially within the interior and having an active configuration and an inactive configuration thus allowing the sensor assembly to be reused, the mechanical switch configured to interact with the cooperating surface on the drug delivery device;
• and
• a communication device in electrical communication with the mechanical switch,
• wherein the mechanical switch is configured to be moveable from the active configuration back to the inactive configuration.