Three-Chambered Autoinjector

Abstract

The present invention relates to a three-chambered autoinjector as well as to the methods of administering medicaments to a human using the three-chambered autoinjector. In certain embodiments, the autoinjector includes a first medicament in liquid form, a second medicament preferably in solid form, and a liquid composition for diluting the second medicament, and utilizes a three-chambered design so as to administer the first medicament and a solution comprising the second medicament and the liquid composition at different injection depths into the body of a human. In an alternative embodiment an autoinjector is provided that delivers medicaments at the same injection depth.

1 . Autoinjector comprising:
 a) a housing having a forward end and a rear end;   b) a rear plunger moveably situated within the housing;   c) a separation assembly moveably situated within the housing, the separation assembly forwardly situated with respect to the rear plunger;   d) a separation plunger moveably situated within the housing, the separation plunger forwardly situated with respect to the separation assembly;   e) a first medicament situated forwardly with respect to the separation plunger, the first medicament in the form of a liquid;   f) a second medicament situated between the separation plunger and the separation assembly;   g) a liquid composition situated between the separation assembly and the rear plunger;   h) a needle having a needle length, a forward end and a rear end, the needle being moveable from a needle storage position in which the needle is situated within the housing to a needle fully extended position in which the needle reaches a maximal extension out of the forward end of the housing; and   i) an activateable power assembly for moving the rear plunger forwardly within the housing.   
     
     
         2 . Autoinjector according to  claim 1 , wherein, after activation of the power assembly, the power assembly causes the separation plunger, the separation assembly, and the rear plunger to move forwardly within the housing and the needle to move from the needle storage position to the needle fully extended position. 
     
     
         3 . Autoinjector according to  claim 1  or  2 , wherein the separation assembly comprises a separation assembly bypass, the separation assembly bypass having a closed position in which the separation assembly bypass prohibits the liquid composition from flowing through the separation assembly and mixing with the second medicament and an open position for allowing the liquid composition to flow through the separation assembly and mix with the second medicament. 
     
     
         4 . Autoinjector according to anyone of  claims 1  to  3 , wherein the housing comprises a punctureable sheath situated over the forward end of the needle so that the needle can puncture through the sheath and extend from the housing after activation of the power assembly. 
     
     
         5 . Autoinjector according to anyone of  claims 1  to  4 , wherein the needle comprises an interior, an exterior, a first opening for allowing the first medicament and a solution comprising the liquid composition and the second medicament to enter into the interior of the needle from the housing, a second opening for allowing the first medicament and the solution to be ejected from the needle, and a passage for allowing the first medicament and the solution to flow through the interior of the needle by entering through the first opening and exiting from the second opening. 
     
     
         6 . Autoinjector according to anyone of  claims 1  to  5 , wherein the autoinjector further comprises a bypass within the housing, the bypass forwardly situated with respect to the separation plunger prior to the activation of the power assembly, the bypass forming a bypass area within the housing for receiving the separation plunger so that when the separation plunger is received in the bypass area, a solution comprising the liquid composition and the second medicament can flow around the separation plunger and into an opening in the needle. 
     
     
         7 . Autoinjector according to anyone of  claims 1  to  6 , wherein the separation plunger rearwardly confines the first medicament. 
     
     
         8 . Autoinjector according to anyone of  claims 1  to  7 , wherein the second medicament is in the form of a solid. 
     
     
         9 . Autoinjector according to  claim 8 , wherein the second medicament is a lyophilized medicament. 
     
     
         10 . Autoinjector according to anyone of  claims 1  to  9 , wherein the liquid composition is an aqueous solution. 
     
     
         11 . Autoinjector having three chambers, the autoinjector comprising:
 a) a housing having a forward end and a rear end;   b) a rear plunger moveably situated within the housing;   c) a separation assembly moveably situated within the housing, the separation assembly forwardly situated with respect to the rear plunger;   d) a separation plunger moveably situated within the housing, the separation plunger forwardly situated with respect to the separation assembly;   e) a first chamber for a liquid composition, the first chamber having a variable volume, the first chamber forwardly confined by the separation assembly and rearwardly confined by the rear plunger;   f) a second chamber for a second medicament, the second chamber having a variable volume, the second chamber forwardly confined by the separation plunger and rearwardly confined by the separation assembly;   g) a third chamber for a first medicament, the third chamber having a variable volume, the third chamber rearwardly confined by the separation plunger;   h) a needle having a needle length, a forward end and a rear end, the needle being moveable from a needle storage position in which the needle is situated within the housing to a needle fully extended position in which the needle reaches a maximal extension out of the forward end of the housing; and   i) an activateable power assembly for moving the rear plunger forwardly within the housing.   
     
     
         12 . Autoinjector according to  claim 11 , wherein, after activation of the power assembly, the power assembly causes i) the rear plunger to move forwardly within the housing so as to decrease the volume of the first chamber; ii) the separation assembly to move forwardly within the housing so as to decrease the volume of the second chamber; iii) the separation plunger to move forwardly within the housing so as to decrease the volume of the third chamber; and iv) the needle to move from the needle storage position to the needle fully extended position. 
     
     
         13 . Autoinjector according to  claim 11  or  12 , wherein the separation assembly comprises a separation assembly bypass for allowing the liquid composition to flow from the first chamber through the separation assembly and into the second chamber. 
     
     
         14 . Autoinjector according to anyone of  claims 11  to  13 , including a first medicament contained in the third chamber, the first medicament in the form of a liquid. 
     
     
         15 . Autoinjector according to anyone of  claims 11  to  14 , including a second medicament contained in the second chamber, the second medicament in the form of a solid. 
     
     
         16 . Autoinjector according to anyone of  claims 11  to  15 , including a liquid composition contained in the first chamber. 
     
     
         17 . Method of administering a first medicament at a first depth and a second medicament at a second depth into the body of a human using an autoinjector, the method comprising the steps of
 a) providing an autoinjector comprising
 i) a housing having a forward end and a rear end; 
 ii) a rear plunger moveably situated within the housing; 
 iii) a separation assembly moveably situated within the housing, the separation assembly forwardly situated with respect to the rear plunger; 
 iv) a separation plunger moveably situated within the housing, the separation plunger forwardly situated with respect to the separation assembly; 
 v) a first medicament situated forwardly with respect to the separation plunger, the first medicament in the form of a liquid; 
 vi) a second medicament situated between the separation plunger and the separation assembly; 
 vii) a liquid composition situated between the separation assembly and the rear plunger; 
 viii) a needle having a needle length, a forward end and a rear end, the needle being moveable from a needle storage position in which the needle is situated within the housing to a needle fully extended position in which the needle reaches a maximal extension out of the forward end of the housing; and 
 ix) an activateable power assembly; 
   b) positioning the autoinjector on the body of the human;   c) activating the power assembly of the autoinjector.   
     
     
         18 . Method according to  claim 17 , wherein the second medicament is in the form of a solid. 
     
     
         19 . Method according to  claim 18 , wherein:
 the separation assembly comprises a separation assembly bypass, the separation assembly bypass having a closed position in which the separation assembly bypass prohibits the liquid composition from flowing through the separation assembly and mixing with the second medicament and an open position for allowing the liquid composition to flow through the separation assembly and mix with the second medicament; and further comprising:   after step (c), opening the separation assembly bypass and flowing the liquid composition through the separation assembly to dissolve the second medicament.   
     
     
         20 . Method according to anyone of  claims 17  to  19 , further comprising:
 moving the separation plunger and the needle forwardly within the housing in response to pressure applied on the separation plunger by the liquid composition. 
 
     
     
         21 . Method according to anyone of  claims 17  to  20 , wherein the needle comprises an interior, an exterior, a first opening for allowing the first medicament and a solution comprising the liquid composition and the second medicament to enter into the interior of the needle from the housing, a second opening for allowing the first medicament and the solution to be ejected from the needle, and a passage for allowing the first medicament and the solution to flow through the interior of the needle by entering through the first opening and exiting from the second opening; the method further comprising:
 after step (c), moving the needle from the needle storage position to the needle fully extended position; and 
 ejecting the first medicament through the second opening in the needle and into the body of the human as the needle moves from the needle storage position to the needle fully extended position. 
 
     
     
         22 . Method according to anyone of  claims 17  to  21 , wherein the needle comprises an interior, an exterior, a first opening for allowing the first medicament and a solution comprising the liquid composition and the second medicament to enter into the interior of the needle from the housing, a second opening for allowing the first medicament and the solution to be ejected from the needle, and a passage for allowing the first medicament and the solution to flow through the interior of the needle by entering through the first opening and exiting from the second opening, and
 wherein the autoinjector further comprises a bypass within the housing, the bypass forwardly situated with respect to the separation plunger prior to the activation of the power assembly, the bypass forming a bypass area within the housing for receiving the separation plunger so that when the separation plunger is received in the bypass area, a solution comprising the liquid composition and the second medicament can flow around the separation plunger and into the first opening in the needle; the method further comprising: 
 after the separation plunger moves into the bypass area, flowing the solution into the first opening in the needle, through the passage in the needle and ejecting the solution from the second opening in the needle into the body of the human. 
 
     
     
         23 . Method according to  claim 22 , further comprising:
 moving the rear plunger and the separation assembly forwardly within the housing as the solution flows through the passage in the needle.   
     
     
         24 . Method according to  claim 23 , wherein the second medicament is in the form of a solid, the method further comprising:
 during the forward movement of the rear plunger, dissolving the second medicament in the liquid composition.   
     
     
         25 . Method according to  claim 23  or  24 , further comprising:
 ceasing the forward movement of the separation assembly within the housing and ceasing the flow of the solution through the passage in the needle. 
 
     
     
         26 . Method according to anyone of  claims 17  to  25 , further comprising
 after step (c), moving the needle from the needle storage position to the needle fully extended position. 
 
     
     
         27 . Method according to  claim 26 , further comprising:
 during the movement of the needle from the needle storage position to the needle fully extended position, delivering the first medicament into the body of the human; and   after the movement of the needle to the needle fully extended position, delivering a solution comprising the liquid composition and the second medicament into the body of the human.   
     
     
         28 . Autoinjector comprising a liquid medicament, a solid medicament and a liquid composition, the autoinjector comprising:
 a) an external housing having a forward end and a rear end;   b) an internal medicament housing moveably received in the external housing;   c) a rear plunger moveably situated within the internal medicament housing;   d) a first separation assembly moveably situated within the internal medicament housing, the first separation assembly forwardly situated with respect to the rear plunger;   e) a second separation assembly moveably situated within the internal medicament housing, the second separation assembly forwardly situated with respect to the first separation assembly;   f) a first medicament situated forwardly with respect to the second separation assembly, the first medicament in the form of a liquid;   g) a second medicament situated between the second separation assembly and the first separation assembly, the second medicament in the form of a solid;   h) a liquid composition situated between the first separation assembly and the rear plunger;   i) a needle having a needle length, a forward end and a rear end, the needle being attached to a forward end of the internal medicament housing; and   j) an activateable power assembly for moving the rear plunger forwardly within the internal medicament housing.