Devices and methods for precision dose delivery

A drug delivery device having a dose expulsion control mechanism, the drug delivery device comprising:

• a barrel including a proximal end and a distal end;
• a plunger rod extending into an interior of the barrel through an opening at the proximal end of the barrel and along a central longitudinal axis of the drug delivery device, the plunger rod including a depressor and a projection having a longitudinal length defined between a proximal portion and a distal portion, the distal portion including a distally-facing surface, wherein the projection is disposed about, and protrudes in a direction perpendicular to, the central longitudinal axis;
• and
• a flange removably coupled to and contacting the proximal end of the barrel, the flange including a body and a hole, the body having a channel along an outer circumference of the flange,
• wherein in an initial configuration, the distally facing surface of the projection is longitudinally spaced apart from a first proximally-facing surface of the flange by a priming distance and the projection is positioned external from the body of the flange prior to an initial stroke of the plunger rod;
• wherein the flange at least partially defines a first path terminating at the first proximally-facing surface, such that the first proximally-facing surface abuts the distally-facing surface after the plunger rod moves the initial stroke through the first path of the flange by the priming distance, thereby positioning the drug delivery device in a primed configuration, and wherein the channel is defined by a second proximally-facing surface that is longitudinally offset from the first proximally-facing surface by a dose delivery distance, the channel is only configured for one stroke that is inhibited by the flange after the initial stroke that causes the distally-facing surface to abut the first proximally-facing surface;
• wherein the flange defines a second path at least partially defined by sidewalls of the channel, and terminating at a closed end of the channel defined by the second proximally-facing surface, such that the second proximally-facing surface abuts the distally-facing surface after the plunger rod moves a final stroke through the second path of the flange by the dose delivery distance, thereby positioning the drug delivery device in a dosage delivered configuration, in the dosage delivered configuration, the flange is configured to inhibit distal and rotational movement of the plunger rod relative to the barrel with the projection positioned against the closed end of the channel;
• and
• wherein the closed end of the channel is configured to receive the distal portion of the projection with the proximal portion of the projection positioned outside the flange and proximal to the hole of the flange when the drug delivery device is in the dosage delivered configuration, wherein the body has a one-piece construction, and the hole has a circumference that is fully enclosed by the body.

A drug delivery device having a dose expulsion control mechanism, the drug delivery device comprising:

• a barrel including a proximal end and a distal end;
• a plunger rod extending into an interior of the barrel along a central longitudinal axis of the drug delivery device, wherein the plunger rod includes a projection protruding radially outward from the central longitudinal axis, and wherein the projection has a length defined between a proximal portion and a distal portion, and the plunger rod is rotatable about the central longitudinal axis;
• and
• a flange removably coupled to the proximal end of the barrel, the flange including a body and an opening, the body including a channel, a first surface, and a second surface that is distal of the first surface, the opening having a geometry configured to receive the plunger rod and the projection is received through the channel when the projection is in alignment with the second surface, wherein the body has a one-piece construction, and the opening has a circumference that is fully enclosed by the body;
• wherein, the body is only configured for one distally-directed priming stroke and one distally-directed dosing stroke of the plunger rod that is inhibited by the flange, such that 1) in an initial configuration of the drug delivery device, the distal portion of the projection is longitudinally spaced from the first surface by a first distance corresponding to the distally-directed priming stroke of the drug delivery device, and not in longitudinal alignment with the second surface, 2) in a primed configuration of the drug delivery device, the distal portion of the projection contacts the first surface of the flange and is not in longitudinal alignment with the second surface, 3) in a dosage delivery configuration of the drug delivery device, the distal portion of the projection is longitudinally spaced from the second surface by a second distance corresponding to the distally-directed dosing stroke of the drug delivery device, and is in longitudinal alignment with the second surface and not in longitudinal alignment with the first surface, and 4) in a delivered configuration of the drug delivery device, the distal portion of the projection contacts and is in longitudinal alignment with the second surface, the proximal portion of the projection is longitudinally spaced from the first surface and positioned proximal to the opening and outside the flange, and the plunger rod is received within the opening;
• wherein the second surface defines a closed end of the channel, and the flange is configured to inhibit distal movement and rotation of the plunger rod relative to the barrel when the distal portion of the projection is positioned against the closed end of the channel, the distal portion of the projection is at least partially visible from outside of the flange when the drug delivery device is in the initial configuration, the primed configuration, the dosage delivery configuration, and the delivered configuration, the first distance is less than the second distance, and the plunger rod is prevented from moving further distally relative to the flange after the projection contacts the second surface.