Claims for Patent: 6,746,429

Summary for Patent: 6,746,429

Title:	Needle assisted jet injector
Abstract:	A needle assisted jet injector and method for jet injecting medicament are disclosed. In one embodiment of the injector, the needle is retractably located within an injector nozzle assembly. Upon activation of the force generating source, a portion of the needle extends past the nozzle assembly and penetrates the outer layer of skin to deliver the medicament via jet injection to a deeper region. After activation, the needle retracts back into the nozzle assembly. In another embodiment, the needle is fixed to the end of the nozzle assembly. In both embodiments, the length of the portion of the needle that penetrates the skin is less than 5 mm.
Inventor(s):	Sadowski; Peter L. (Woodbury, MN), DeBoer; David M. (Brighton, MI), Berman; Claude L. (Ypsilanti, MI), Lesch, Jr.; Paul R. (Lexington, MN), Holland; Margaret L. (Rochester, NY)
Assignee:	Antares Pharma, Inc. (Minneapolis, MN)
Application Number:	09/779,603
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,746,429
Patent Claims:	1. A jet injection device comprising: a housing having distal and proximal ends; a fluid chamber having a seal at one end and located within said housing for holding at least about 0.02 ml to 3 ml of a medicament; an injection-assisting needle having an injecting end and a piercing end and coupled to the distal end of said housing and moveable between a medicament storing position and a medicament delivering position wherein said needle is isolated from said fluid chamber when said needle is in said medicament storing position and said piercing end punctures the seal to provide a fluid pathway from the fluid chamber through the needle when said needle is in said medicament delivering position, wherein the needle has a tip with a length of approximately 1-5 mm; a plunger movable within the fluid chamber; a force generating source capable of providing sufficient force on the plunger to eject an amount up to about 3 ml of the medicament from the fluid chamber in less than 2.75 seconds; a needle guard located at the distal end of said housing for concealing said needle, the needle guard being moveable between a protecting position and an injecting position; and an activation element operatively associated with the needle guard; wherein the needle is located within the needle guard prior to activation of the force generating source so that retraction of the needle guard exposes the injecting end of said needle to an insertion point and activation of the force generating source moves the plunger to expel medicament from said fluid chamber and thereby eject the amount of the medicament through the injecting end of said needle and past the needle insertion point to an injection site in less than 2.75 seconds, the needle insertion point being located at the injecting end of the needle, and the injection site being distal to the injecting end of the needle, and wherein the medicament is ejected at a pressure between around 100 and 1000 p.s.i. and at a rate of at least 0.40 ml/sec. 2. The injection device of claim 1, wherein retraction of the needle guard from the protecting position to the injecting position activates the force generating source and the force generating source provides sufficient force to eject an amount of about 1 to 2 ml of the medicament in less than about 2.5 seconds. 3. The injection device of claim 2, further comprising a locking element associated with the needle guard for locking the needle guard in the protecting position after activation of the injection device and after return of said needle guard to the protecting position. 4. The injection device of claim 1, wherein the activation element comprises: an inner housing located inside the housing and having trigger projections for maintaining the plunger in an idle position; and a latch located inside the housing and circumferentially surrounding the inner housing, the latch being moveable between a firing position and an armed position; wherein retraction of the needle guard to the injecting position urges the latch toward the firing position, thereby releasing the trigger projections from the plunger and activating the injection device. 5. The injection device of claim 1, further comprising an elastomeric element acting upon the needle guard and urging the needle guard toward the protecting position; wherein the elastomeric element returns the needle guard to the protecting position after the medicament has been ejected from the needle, thereby substantially re-enclosing the needle. 6. The injection device of claim 1, wherein the needle is mounted on a needle holder operatively associated with the needle and the distal end of the housing, such that rotation of the needle holder places the needle in fluid communication with the fluid chamber. 7. The injection device of claim 1, further comprising a removable safety cup operatively associated with the distal end of the injection device such that rotation of the safety cap imparts rotation on the needle. 8. A jet injection device comprising: a housing having distal and proximal ends; a fluid chamber within the housing for holding at least about 0.02 ml to 3 ml of a medicament; an injection-assisting needle disposed at the distal end of the housing, having an injecting end, and having an association with the fluid chamber to provide a fluid pathway from the fluid chamber through the needle; a plunger movable within the fluid chamber; and a force generating source capable of providing sufficient force on the plunger to eject an amount up to about 3 ml of the medicament from the fluid chamber in less than 2.75 seconds; wherein the injecting end of the needle has a position with a tip having a length of approximately 1-5 mm exposed from the housing for insertion into a patient to an insertion point, and activation of the force generating source moves the plunger to expel medicament from the fluid chamber and thereby eject the amount of the medicament by a pressure between around 100 and 1000 p.s.i. through the injecting end and past the insertion point to an injection site in less than 2.75 seconds, the needle insertion point being located at the injecting end of the needle, and the injection site being distal to the injecting end of the needle. 9. The injection device of claim 8, wherein at least a portion of the housing is made of a transparent or translucent material for allowing viewing of the fluid chamber, and the medicament is ejected at a pressure between around 100 to 500 p.s.i. and at a rate of about 0.50 ml/sec so that about 1 ml of the medicament is ejected in about 2 seconds. 10. The injection device of claim 8, further comprising a needle guard located at the distal end of the housing for concealing the needle, the needle guard being moveable between: a protecting position, in which the needle is disposed within the guard prior to activation, and an injecting position, in which the tip of the needle is exposed for insertion to the insertion point. 11. The injection device of claim 10, further comprising an activation element operatively associated with the needle guard such that the activation element activates the force generating source upon retraction of the needle guard from the protecting position to the injection position. 12. The injection device of claim 8, wherein the force generating source is configured to move the plunger to expel medicament from the fluid chamber at a rate of at least 0.40 ml/sec. 13. The injection device of claim 8, wherein said pressure is within the fluid chamber to expel the medicament. 14. The injection device of claim 1, wherein said fluid chamber comprises: an ampule having a distal end, a proximal end and an opening in each of the distal and proximal ends; a pierceable seal associated with the opening in the distal end; and a stopper located in the proximal end of the ampule for maintaining the medicament inside the ampule. 15. The injection device of claim 14, wherein activation of the force generating source moves the pierceable seal towards the injection assisting needle to pierce the seal and moves the stopper to eject medicament from the injection assisting needle.