Drug delivery devices, systems, and methods

1. A drug delivery device, comprising:

an elongate member defining a fluid passage and an opening in fluid communication with the fluid passage;

an introducer needle disposable within the elongate member for insertion of the elongate member into a patient's skin; and

a projection extending radially from the elongate member,

wherein a portion of the elongate member extending axially from the projection to a distal end of the elongate member has a length sufficient to allow the distal end of the elongate member to reach subdermal tissue of a patient when the elongate member is inserted into the patient and the projection is in contact with an outer surface of skin of the patient, and the opening is positioned at a location along the elongate member such that the opening is disposed within a dermis of the patient when the elongate member is inserted into the patient and the projection is in contact with the outer surface of the skin of the patient; and

wherein a portion of the elongate member between the opening and the distal end of the elongate member comprises a self-sealing material to seal the distal end of the elongate member subsequent to removal of the introducer needle.

2. The drug delivery device of claim 1 , wherein the portion of the elongate member extending axially from the projection to a distal end of the elongate member has a length of at least about four millimeters, and the opening is positioned at a location that is axially spaced from the projection by no more than about 2.5 millimeters.

3. The drug delivery device of claim 2 , wherein the portion of the elongate member extending axially from the projection to the distal end of the elongate member has a length of at least about five millimeters.

4. The drug delivery device of claim 1 , wherein the portion of the elongate member extending axially from the projection to the distal end of the elongate member has a length of about four millimeters to about nine millimeters.

5. The drug delivery device of claim 1 , wherein the opening is positioned at a location that is axially spaced from the projection by about 0.3 millimeter to about 2.5 millimeters.

6. The drug delivery device of claim 1 , wherein the self-sealing material comprises a polymeric material.

7. The drug delivery device of claim 1 , further comprising at least one feature extending radially from the portion of the elongate member between the opening and the distal end of the elongate member.

8. The drug delivery device of claim 7 , wherein the feature comprises a barb.

9. The drug delivery device of claim 1 , wherein the passage terminates proximal to the distal end of the elongate member.

10. The drug delivery device of claim 9 , wherein the passage terminates at the opening.

11. The drug delivery device of claim 1 , wherein the elongate member has a sharp distal tip.

12. The drug delivery device of claim 11 , wherein the sharp distal tip is not in fluid communication with the passage.

13. The drug delivery device of claim 1 , wherein the elongate member defines a plurality of openings in fluid communication with the passage, and the plurality of openings are positioned at locations along the elongate member such that the openings are disposed within the dermis of the patient when the elongate member is inserted into the patient and the projection is in contact with the outer surface of the skin of the patient.

14. The drug delivery device of claim 13 , wherein the plurality of openings are circumferentially spaced around the elongate member.

15. The drug delivery device of claim 13 , wherein the plurality of openings are axially spaced along the elongate member.

16. A drug delivery device, comprising:

an elongate member defining a fluid passage and an opening in fluid communication with the fluid passage;

an introducer needle disposable within the elongate member for insertion of the elongate member into a patient's skin; and

a projection extending radially from the elongate member,

wherein a portion of the elongate member extending axially from the projection to a distal end of the elongate member has a length sufficient to allow the distal end of the elongate member to reach subdermal tissue of a patient when the elongate member is inserted into the patient and the projection is in contact with an outer surface of skin of the patient, and the opening is positioned at a location along the elongate member such that the opening is disposed within a dermis of the patient when the elongate member is inserted into the patient and the projection is in contact with the outer surface of the skin of the patient; and

wherein a portion of the elongate member between the opening and the distal end of the elongate member comprises a valve to seal the distal end of the elongate member subsequent to removal of the introducer needle.

17. A drug delivery device, comprising:

an elongate member having a fluid passage;

an introducer needle insertable within the elongate member to assist in insertion of the elongate member into a patient's skin; and

a projection that extends radially from the elongate member and that contacts the skin and limits the depth of the insertion of the distal end of the elongate member to the level of subdermal tissue;

wherein the elongate member has an opening along the fluid passage that is located at a dermis level of the tissue while the projection is contacting the skin; and

wherein the device further comprises a valve disposed in the elongate member between the distal end and the opening of the elongate member.