Devices and methods for precision dose delivery

A drug delivery device, comprising:

• a barrel;
• a plunger disposed within the barrel;
• a plunger rod disposed within the barrel via a proximal opening of the barrel, wherein the plunger rod extends along a longitudinal axis of the barrel, and is coupled to the plunger in a one-piece construction such that the plunger rod and the plunger are formed in a single mold;
• and
• a stop that is configured to move between a first configuration, in which the stop is configured to inhibit translation of the plunger rod distally relative to the barrel once the plunger rod initially translates distally relative to the barrel by a priming distance, to a second configuration in which the stop is configured to permit translation of the plunger rod distally relative to the barrel.

A drug delivery device, comprising:

• a barrel;
• a flange coupled to a proximal end of the barrel, the flange including a body and a hole;
• a plunger disposed within the barrel;
• and
• a plunger rod including a depressor, wherein the plunger rod is disposed within the hole of the flange and the barrel via an opening at the proximal end of the barrel, wherein the plunger rod extends along a longitudinal axis of the barrel, and is formed in a one-piece construction with the plunger;
• a stop that is configured to move between a first configuration, in which the stop is configured to inhibit translation of the plunger rod distally relative to the barrel once the plunger rod initially translates distally relative to the barrel by a priming distance, to a second configuration in which the stop is configured to permit translation of the plunger rod distally relative to the barrel.

A method of dispensing a drug from a drug delivery device, comprising:

• translating a plunger rod of the drug delivery device distally relative to a barrel of the drug delivery device by a predetermined distance until distal translation of the plunger rod is resisted by a stop of the drug delivery device;
• deactivating the stop to cease resistance against the distal translation of the plunger rod relative to the barrel;
• and
• translating the plunger rod distally relative to the barrel to deliver the drug from the drug delivery device.