Automated injection system

Abstract

The present invention provides an automated injection system for transdermal or intradermal delivery of a medicament or the like that provides a robust and yet greatly simplified manner of operation, the system comprising an elongate housing forming a handle, an array of five microneedles located at one end of the elongate housing, the injection system further comprises an internal reservoir of the medicament to be injected through the microneedle, and an actuator assembly housed within the housing, the actuator assembly being arranged to allow a user to operate the injection system through a simple one-hand grip and press action, to insert the microneedle into the skin and to automatically inject the medicament.

Description

Technical Field

[0001] The present invention relates to an automated injection system, and in particular to an injection system for transdermal or intradermal delivery of a medicament or the like, which injection system provides a robust yet greatly simplified mode of operation and thereby allows reliable self-injection. Background Art

[0002] Chronic diseases and conditions are becoming more and more common, in part due to changes in social behavior and an aging population. The use of biologics (including antibodies, therapeutic proteins, peptides, and cell-based therapies) for therapeutic treatment provides significant advantages in efficacy and selectivity, and their use in the treatment of cancer and cancer-related diseases, rare diseases, neurological disorders, and autoimmune diseases is increasing. However, the specific physicochemical properties of biologics (including high viscosity) mean that it may be challenging to deliver them as active agents into the body, which necessitates intravenous (IV) or subcutaneous administration. The emergence of patient-centric "auto-injector" designs and devices allows users in various chronic disease states to routinely self-administer subcutaneous medications at home, which is advantageous because it eliminates the need to go to a hospital or infusion center.

[0003] However, there are several limitations in existing subcutaneous automatic injectors. In these prior art designs, the medicament is usually administered via a single needle inserted vertically through the skin. Common needle insertion methods involve utilizing the potential energy stored in a spring, such as pushing the needle through the skin with considerable speed and force. In addition to causing potential pain and discomfort to the patient, this action sometimes causes the needle to break. Depending on factors such as the volume and viscosity of the medicament, it may then take a few seconds to a few minutes of "holding time" to administer the automatic injection (and this usually requires a second stored potential energy source). For elderly patients and those with dexterity problems and / or tremor symptoms, it may be challenging to maintain a consistent, stable hand during this injection phase. It is well known that high-viscosity biological agents are associated with long injection and "holding" times. A strategy to reduce injection time and therefore "holding time" is to reduce viscosity while retaining the payload by re-formulating the medicament, but this makes it necessary to have a larger injection volume, thereby placing further requirements on device engineering and affecting the patient's experience.

[0004] The skin as a delivery site for both biologics and vaccines (intradermal delivery) offers unparalleled efficiency (ie, dose sparing) and efficacy (ie, dose-response).

[0005] However, for various reasons, such as the experience of the applicator and the accuracy required to correctly perform the procedure, the location and / or condition of the delivery site, the limited thickness of the skin and the required delivery depth, etc., this form of delivery using the so-called Mantoux technique may be difficult or time-consuming to perform. Therefore, this form of injection is generally not suitable for self-injection. This is especially true for individuals with reduced dexterity, poor eyesight or other physical impairments that may increase the difficulty of performing the routine task of intradermal injections. The use of a single needle to deliver high-viscosity medicaments also poses considerable challenges.

[0006] Therefore, there is a need for an intradermal injection system that is easy to use, reliable and repeatable for self-injection. There is also a need for an injection system that can rapidly deliver vaccines and viscous biologics with reduced injection pressure and that can be easily manipulated by all types of patients.

[0007] Therefore, an object of the present invention is to solve the above-mentioned problems. Summary of the invention

[0008] According to the present invention, an automated injection system is provided, which includes: an elongated shell defining a handle; an actuator assembly, which is disposed within the shell and can be longitudinally displaced relative to the shell; an injection head, which is mounted to the actuator assembly and protrudes from the open lower end of the shell, the injection head including a pair of jaws which can be displaced relative to each other in a direction transverse to the longitudinal axis of the shell in response to the relative longitudinal displacement between the shell and the actuator assembly, each jaw having one or more hollow microneedles protruding therefrom; a reservoir of liquid contained in the shell, the reservoir being connected to one or more fluids in the hollow microneedles; and a dispenser, which can be operated to pressurize the fluid in the reservoir in response to the relative longitudinal displacement between the shell and the actuator assembly so as to dispense the liquid from the one or more hollow microneedles.

[0009] Preferably, the reservoir is defined by a syringe comprising a barrel closed at one end by a piston which can be displaced into the barrel by the dispenser in order to pressurize the fluid.

[0010] Preferably, the dispenser includes a spring biased plunger operatively associated with the piston.

[0011] Preferably, the plunger comprises an abutment and the actuator assembly comprises a latching member, the abutment being releasably retained against the latching member.

[0012] Preferably, the actuator assembly is operable to effect displacement of the latch member out of engagement with the abutment either sequentially before or after completion of relative lateral displacement of the pair of jaws.

[0013] Preferably, the actuator assembly comprises a biasing element arranged to urge the latch member out of engagement with the abutment following relative longitudinal displacement between the housing and the actuator assembly.

[0014] Preferably, the biasing element comprises a guide member fixed to the housing and displaceable against the latch member in response to relative longitudinal displacement between the housing and the actuator assembly so as to urge the latch member out of engagement with the abutment.

[0015] Preferably, one of the jaws and the housing comprises a cam having a profile arranged to effect relative lateral displacement of the pair of jaws in response to relative longitudinal displacement between the housing and the actuator assembly and the other of the jaws and the housing comprises a corresponding follower.

[0016] Preferably, each jaw comprises a cam and the housing comprises a corresponding pair of followers.

[0017] Preferably, the actuator is arranged for rotational displacement in response to relative linear displacement of the housing.

[0018] Preferably, the injection head is operable to convert rotational displacement of the actuator assembly into relative lateral displacement of the pair of jaws.

[0019] Preferably, the or each cam is shaped to permit two stage displacement of the jaws, the first stage being configured to effect relative lateral displacement of the jaws in response to relative longitudinal displacement between the housing and the actuator assembly, and the second stage permitting relative movement between the jaws in the absence of relative longitudinal displacement between the housing and the actuator assembly.

[0020] Preferably, the or each cam is profiled to define a third phase between the first and second phases, the third phase permitting relative longitudinal displacement between the housing and the actuator assembly in the absence of relative lateral displacement of the jaws.

[0021] Preferably, the injection head comprises at least one release member manually operable to reverse the relative lateral displacement between the pair of jaws.

[0022] Preferably, the housing comprises an aperture in the side wall through which the release member is accessible following relative longitudinal displacement between the housing and the actuator assembly.

[0023] Preferably, the injection system comprises a longitudinally displaceable sleeve on the housing, the longitudinally displaceable sleeve being displaceable into engagement with the at least one release member to reverse the relative lateral displacement between the pair of jaws.

[0024] Preferably, the injection system comprises a locking element operable to prevent reversal of the relative longitudinal displacement between the housing and the actuator assembly.

[0025] Preferably, the actuator assembly comprises an elongate frame about which the housing is supported and within which the reservoir is received, the injection head being mounted at one end of the frame.

[0026] Preferably, the hollow microneedles on each jaw are angled toward the hollow microneedles on the other jaw.

[0027] Preferably, the injection system comprises a cap releasably fastenable about the lower end of the housing to enclose the injection head.

[0028] Preferably, the automated injection system comprises a spring arranged to urge the housing longitudinally along the actuator assembly.

[0029] Preferably, the spring comprises a leaf spring disposed between the actuator assembly and the closed end of the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will now be described with reference to the accompanying drawings, in which:

[0031] Figure 1a shows a front elevation view of an embodiment of an automated injection system according to the present invention in an undeployed state;

[0032] Figure 1b shows the automated injection system of FIG. 1 in a deployed state;

[0033] Figure 1c 1 and 2 in a released state;

[0034] Figure 2a It shows that Figure 1a A cross-sectional view of the injection system shown;

[0035] Figure 2b It shows that Figure 1b A cross-sectional view of the injection system shown;

[0036] Figure 2c It shows that Figure 1b The injection system is shown after actuation of the syringe;

[0037] Figure 2d It shows that Figure 1c A cross-sectional view of the injection system shown;

[0038] Figure 3a , Figure 3b and Figure 3c It shows that Figure 1a , Figure 1b and Figure 1c An enlarged view of the injection head of the automated injection system is shown;

[0039] Figure 4a , Figure 4b and Figure 4c An actuation assembly forming part of the automated injection system shown in FIGS. 1 to 3 is shown in partially exploded and assembled views;

[0040] Figure 5 shows a perspective view of the automated injection system of FIGS. 1 to 4 in an undeployed state;

[0041] Figure 6 Figure 1 shows Figure 5 An exploded perspective view of an automated injection system;

[0042] Figure 7a , Figure 7b and Figure 7c Figure 1 shows the formation of Figure 6 Various exploded perspective views of an injection head and a syringe coupling as part of an automated injection system;

[0043] Figure 8a , Figure 8b and Figure 8c It shows that Figure 7a , Figure 7b and Figure 7c Various front elevation views of the visible injection head and syringe coupling;

[0044] Fig. 9 showing a perspective view of an alternative embodiment of an automated injection system according to the present invention in an undeployed state;

[0045] Fig.10 Shows Fig. 9 A perspective view of an alternative embodiment of the invention in a deployed state;

[0046] Fig.11a It shows that Fig. 9 A cross-sectional view of the automated injection system shown;

[0047] Fig.11b It shows that Fig.10 A cross-sectional view of the automated injection system shown;

[0048] Fig.11c Shows Fig. 9 and Fig.10 An automated injection system in a released state;

[0049] Fig.12ashowing a front elevation view of a further alternative embodiment of an automated injection system according to the present invention and in an undeployed state;

[0050] Figure 12b It shows that Fig.12a A cross-sectional view of the automated injection system shown;

[0051] Fig.12c Shows Figure 12b The automated injection system in deployment;

[0052] Fig.13a It shows that Fig.12a and Figure 12b A cross-sectional perspective view of the automated injection system is shown;

[0053] Fig.13b It shows that Fig.13a One half of the housing of the automated injection system is visible in the figure and is in an undeployed state;

[0054] Fig.13c Shows the deployed state Fig.13b Shell;

[0055] Fig.14 A perspective view showing a two-part automated injection system in a partially separated state according to yet another alternative embodiment of the present invention;

[0056] Fig.15 Shows Fig.14 A front elevation view of an injection system;

[0057] Fig.16 Shows Fig.14 and Fig.15 An assembly diagram of the injection system shown;

[0058] Fig.17 shows a front elevation view of another embodiment of an automated injection system according to the present invention in an undeployed state;

[0059] Fig.18 Shows Fig.17 A side elevation view of an automated injection system;

[0060] Fig.19 It shows that Fig.17 and Fig.18 The injection system is shown after a pair of jaws are engaged and the syringe is actuated;

[0061] Fig. 20 Shows Figures 17 to 19 the injection system after the pair of jaws are retracted by telescoping action of the housing of the injection system;

[0062] Fig.21 showing a perspective view of a lower portion of a further alternative embodiment of an automated injection system according to the present invention with a pair of jaws in an undeployed state;

[0063] Fig. 22 Shows Fig.21 A plan view of the lower portion shown;

[0064] Fig.23 Shows Fig.21 and Fig. 22 a plan view from below of the injection system with the pair of jaws in an undeployed state; and

[0065] Fig.24 An automated injection system is shown as in Figure 213 but with a pair of jaws in a deployed state. DETAILED DESCRIPTION

[0066] Referring now to Figures 1 to 8 of the accompanying drawings, there is shown an automated injection system, generally indicated at 10, which is operable to provide a simple and consistent manner of injecting a fluid medicament (not shown) or the like into tissue, particularly for intradermal delivery, and most preferably allowing such injections to be performed using a single hand, and thereby permitting self-injection.

[0067] The injection system 10 includes an elongated and substantially cylindrical housing 12 which, in use, defines a pistol grip type handle by which the injection system 10 is held and operated, and thus the length and diameter of the housing 12 are sized accordingly to comfortably fit within the hand of a user. The housing 12 may be formed of any suitable material or combination of materials, and may be formed, for example, by injection molding of a plastic. The housing 12 includes a closed upper end 14 and an open lower end 16 from which extends an injection head 18. The injection head 18 includes a pair of opposing jaws 20 from which a plurality of hollow microneedles 22 protrude from a lower surface of each of the jaws, the hollow microneedles being inclined in a direction toward the opposing jaws 20. As described in detail below, the injection system 10 is operable to automatically insert the array of microneedles 22 into the skin or other tissue, and then inject a liquid medicament when the user grasps the housing 12 and presses the injection head 18 against the skin, thereby allowing a simple, one-handed procedure to be performed.

[0068] Refer to Figure 2 and Figure 6 , shows the interior of the injection system 10, which includes an actuator assembly 24 captured within the housing 12 and adapted to be longitudinally displaced relative to the housing 12 to implement various operational automation functions as described below. Figure 6As shown, the housing 12 is preferably manufactured as a clamshell structure, which includes a pair of halves that are snap-fitted or otherwise fastened together to capture the actuator assembly 24 therebetween. A pair of parallel guide rails 25 may be integrally formed within the interior of the housing 12 to guide the actuator assembly 24 during relative longitudinal displacement.

[0069] The actuator assembly 24 includes Figures 4a to 4c 1 and 2, within which is mounted a syringe 28 containing a liquid medicament for injection. The frame 26 is preferably formed of a polymer, but any other suitable material may be used. The injection head 18 is mounted at the lower end of the frame 26 to protrude from the lower end 16 of the housing 12 and is in fluid communication with the syringe 28. As a result, and with reference to both FIG. 1 and FIG. 2, the housing 12 can therefore be moved relative to the actuator assembly 24 and the injection head 18 as shown in FIG. Figure 1a and Figure 2a The undeployed state or condition shown is longitudinally displaced to Figure 1b and Figure 2b The deployed state or condition shown, in which the microneedles 22 are placed in contact with the skin in the non-deployed state, in which the microneedles 22 are inserted into the skin by relative longitudinal displacement between the housing 12 and the actuator assembly 24. As described in detail below, this is achieved by converting the relative longitudinal displacement between the housing 12 and the actuator assembly 24 into a relative displacement between the pair of jaws 20 in a direction transverse to the longitudinal displacement direction. For reference, the injection system 10 is preferably maintained substantially perpendicular to the skin when in use, wherein the longitudinal axis of the housing 12 defines the longitudinal displacement direction, and the jaws 20 will therefore be displaced transverse to this direction, and therefore generally parallel to the surface of the skin. This transverse or lateral displacement acts to insert the tilted microneedles 22 into the skin, wherein the opposing sets of microneedles 22 overlap and act to grasp the skin in between, and thereby hold or anchor the microneedles 22 in place, so as to ensure stability during use, and therefore ensure accurate and consistent injection of liquid medicament. This anchoring action has been described in detail in the earlier international application WO2018 / 069543, and therefore no further explanation is required for this particular aspect of the invention.

[0070] Once the microneedles 22 have been partially or completely anchored in the skin or other tissue, the final longitudinal displacement of the housing 12 toward the skin and relative to the actuator assembly 24 will enable the operation of the injector 28 to inject the liquid agent through the microneedles 22 and into the surrounding tissue, as will be described in detail below. Figure 2c After this, the injection system 10 can be manually operated to release the microneedle 22 from the skin, so that the injection system 10 can be disengaged and withdrawn, as shown in FIG. Figure 1cand Figure 2d This action will be described again in detail below.

[0071] Thus, the primary function of the automated injection system 10 is to allow a single, simple action, i.e., using the housing 12 as a handle to press the injection head 18 against the skin to automatically achieve a plurality of operations that together insert the microneedle 22 into the skin and then inject the fluid from the syringe 28 through the embedded microneedle 22. To achieve the first stage of the injection operation, the pair of jaws 20 are arranged to be displaced transversely or laterally relative to each other in response to the longitudinal displacement of the housing 12 relative to the actuator assembly 24 under downward pressure applied by the user via the housing 12. The pair of jaws 20 interlock with each other, Figure 7a The jaws 20 are shown completely separated from each other prior to assembly with the frame 26. Figure 7b The jaws 20 are shown put together for assembly, while Figure 7c The jaws 20 are shown interlocked and ready to be received and secured to the frame 26 and disposed within the housing 12 during operation. Figure 8a Shows Figure 7c The front elevation view of the arrangement visible in Figure 8b The front elevation view shows the frame 26 pushed down between the jaws 20, and Figure 8c The jaws 20 are shown having been displaced relative to one another in order to be coupled to the frame 26 , as described below.

[0072] When interlocked, the jaws 20 are capable of limited translational displacement relative to each other so as to slide the microneedles 22 on each jaw 20 toward each other, thereby engaging and embedding the microneedles 22 into the skin. Each jaw 20 includes an inner wall 30, which is in face-to-face contact with each other and therefore preferably has a smooth surface finish to allow the jaws 20 to slide against each other with limited friction. The jaws 20 also include upstanding tabs 36 that define an enclosure or space between which the lower end of the frame 26 and a fluid manifold 38 are located, and the fluid manifold 38 is captured between the upper surface 40 of the pair of jaws 20 and the clamping track 42 to secure the injection head 18 to the frame 26 of the actuator assembly 24. As shown from Figure 5As can be appreciated in the drawings, the upstanding tabs 36 provide a visual shield to hide the internal components of the device from the user. The tapered contact surfaces on the fluid manifold 38 and the clamping rails 42 ensure a fluid-tight seal between the fluid manifold 38 and the upper surface 40 of the jaws 20. One or more fluid conduits 32 extend from each upper surface 40, through the jaws 20, to the corresponding microneedle 22. In this way, a fluid path is established from the syringe 28, through the fluid manifold 38 and the jaws 20 to the microneedle 22. An example of such an interface between the pair of jaws 20, the fluid manifold 38 and the syringe 26 is described and illustrated in detail in the applicant's international application PCT / EP2022 / 062653, and therefore no further explanation of the configuration and operation of this aspect of the invention is required.

[0073] Each jaw 20 also includes a cam 44 in the form of a channel formed in an outer surface 46 of the jaw 20, the cam being offset from the inner wall 30 and being located between the pair of jaws 20. Figure 7c The interlocking case shown is arranged to be positioned above and aligned with the lower portion of the opposing jaws 20. The cam 44 is shaped to define a first phase 48 extending both downwardly and laterally outwardly, and a second phase 50 extending laterally from the open lower end of the channel only along the underside of the outer surface 46 of the jaws 20. The housing 12 is provided with a corresponding pair of followers 52 (see FIGS. 3 and Figure 6 ), in the form of a pair of opposed pins 52, each projecting from an inner surface of the housing 12 on opposite sides thereof so as to be captured within a respective cam 44. The follower 52 is positioned on the housing 12 so that, with the injection system 10 in an undeployed state, the follower 52 is seated in the upper end of a channel defining the cam 44, e.g. Figure 3a As shown, this corresponds to Figure 1a and Figure 2a Therefore, it should be understood that during the process of pressing the housing 12 against the skin, the relative longitudinal displacement between the housing 12 and the injection head 18 drives the follower 52 from Figure 2a and Figure 3a The position shown is reached along the cam 44 downwards Figure 2b and Figure 3b Thus, the orientation of the first phase 48 of the cam 44 will cause the corresponding jaw 20 to shift laterally toward the other jaw 20, thereby shifting the microneedle 22 across the skin into which the microneedle 22 is pressed by the pressure being applied by the user to the housing 12. This action causes the angled microneedles 22 to be inserted into the skin, and the overlapping array of microneedles 22 anchors the injection head 18 to the skin to allow uninterrupted injection of liquid medication from the syringe 28.

[0074] The second phase 50 of the cam 44 allows the jaws 20 to be displaced in the opposite direction or away from each other so as to withdraw the microneedle 22 from the skin after the injection of the fluid, details of which will be provided below. Once the follower 52 is moved out of the open lower end of the channel defining the cam 44, the second phase 50 of the action of the cam 44 and the follower 52 is entered, whereby the follower 52 can be displaced laterally relative to the jaw 20, thereby moving along the lower side or lower edge of the outer surface 46. The second phase 50 can include a shallow detent in the lower edge of the outer surface 46 to define a stop or limit to the lateral movement of the jaw 20. It should be understood that the positions of the cam 44 and the follower 52 can be reversed, wherein the cam is formed in the wall of the housing 12 and the follower is provided on the outer surface of the jaw 20. It should also be understood that the second phase 50 of the cam 44 can be formed as a lateral extension of the channel in the outer surface 46, rather than being defined below the outer surface 46. Thus, the term "cam" is intended to refer to one or more elements that define a fixed path along which another element, such as a follower 52, is restricted from traveling in order to impart a desired sequence of motion to a working component, in this case the jaws 20. In this embodiment, the fixed path includes two distinct phases, the first phase 50 being the travel along and within a channel in the cam 44, and the second phase being the travel when the follower 52 exits the channel and is then free to move laterally along the underside of the outer surface 46. However, it should be appreciated that these two phases of motion may be achieved by other mechanically constructed components that act to impart the necessary travel path to the pair of jaws 20. It should also be appreciated that, as described below with respect to alternative embodiments, the second phase of displacement may simply be a reversal of the first phase.

[0075] Turning to the operation of the syringe 28, the frame 26 of the actuator assembly 24 includes a pair of elongated side members 54 which, together with a cross member 56 and the lower end of the frame 26, define an enclosure in which the barrel 58 of the syringe 28 is located and retained. A dispenser or plunger 60 of the syringe 28 extends through the cross member 56 and terminates in an abutment or head 62 which is positioned toward the upper end 14 of the housing 12 when the syringe is filled and ready for use. The elongated side members 54 extend longitudinally beyond the cross member 56 and, although the free ends 64 of the side members 54 are connected by a loop of flexible material forming a leaf spring 66, the free ends 64 of the side members 54 effectively define cantilever arms which are thus elastically deformable away from each other in a transverse or lateral direction as described below. The leaf spring 66 acts against the closed upper end 14 of the housing 12 to maintain the actuator assembly 24 and the housing 12 in an undeployed relative position. The leaf spring 66 has sufficient bias to maintain the housing 12 in the longitudinal position in the absence of external pressure, but is weak enough to be easily overcome by a user grasping the housing 12 and pressing the injection head 18 against the skin to achieve relative longitudinal displacement of the housing 12 and the actuator assembly 24 under the bias of the leaf spring 66. The leaf spring 66 can be formed of any suitable material and can be integrally molded with the side member 54, such as a polymer or the like.

[0076] The actuator assembly 24 also includes a compression spring 68 disposed about the plunger 60 and captured and compressed between the upper surface of the piston (not shown) of the syringe 28 and the cross member 56, thereby applying a biasing force to the piston to push the plunger 60 into the barrel 58 to push the liquid medicament out of the barrel 58. However, the free end 64 of the side member 54 engages below the head 62 and thereby acts as a latch member that prevents the compression spring 68 from depressing the plunger 60. The actuator assembly 24 includes a pair of guide members in the form of ramps 70 that protrude from the inner wall of the housing 12 adjacent the upper end 14 and are in a certain position to engage the free ends 64 of the side members 54 and displace the free ends laterally and thereby disengage from engagement with the head 62 in response to longitudinal displacement of the housing 12 relative to the actuator assembly 24. In particular, the thin end of each ramp 70 defines the proximal end of the ramp 70 relative to the displacement direction of the housing 12, and the thin end therefore initially contacts the end of the side member 54 adjacent to the free end 64, whereupon further longitudinal displacement of the housing 12 drives the ramp 70 relative to the side member 54 and achieves its lateral displacement. The side member 54 can be elastically deformed to allow such deflection of the free end 64. The side member 54 can be formed, for example, of any suitable polymer or the like. The position and size of the ramp 70 are designed so that the free end 64 is separated from the head 62 only after the pair of jaws 20 has made their full relative displacement, so that the microneedle 22 is fully embedded in the skin and remains stable. It should be understood that the ramp 70 is merely an exemplary form of a mechanical arrangement that can be operated to convert the longitudinal displacement of the housing 12 into a lateral displacement of the side member 54 or otherwise latch the head 62, and any other functional alternatives can be adopted.

[0077] Once the free end 64 has been deformed laterally or sideways away from the head 62, the bias of the spring 68 is free to drive the piston (not shown) downwardly along the barrel 58 of the syringe 28 to force the liquid medicament through the microneedle 22 and into the tissue. Figure 2c The injection system 10 is shown at this stage with the free end 64 deformed outwardly and the plunger 60 depressed so that the spring 68 is uncompressed. The housing 12 is preferably provided with a window 72 adjacent the barrel 58 of the syringe 28 to allow the user to visually confirm that the liquid medicament has been dispensed and thus injected into the skin or other tissue.

[0078] At this point, the injection system 10 has completed the injection of the medicament and should be removed, but the microneedle 22 is still embedded in the skin and must therefore be retracted, after which the injection system 10 can be disengaged. In order to retract the microneedle 22, it is necessary to reverse the relative lateral displacement of the jaws 20. To facilitate this action, the housing 12 is provided with a pair of lateral openings 74 proximal to the lower end 14, each of the openings 74 being positioned to receive a release member in the form of a button 76 protruding from the upright tab 36 of each jaw 20. The openings 74 are elongated in the longitudinal direction so as to accommodate the button 76 during the relative longitudinal displacement between the housing 12 and the injection head 18. In addition, when the jaws 20 are displaced laterally together, the button 76 will be displaced laterally outward to protrude further from the opening 76. The housing 12 may taper inwardly in the area of ​​the opening 76 to define a narrow waist at the upper end of the opening 76 to further expose the button 76 when the housing 12 has been fully pressed against the skin and the injection head 18 has been substantially displaced into the housing 12 through the open lower end 16 .

[0079] Therefore, it should be understood that once the medicament has been injected, the jaws 20 can be displaced back to the undeployed state by the user squeezing the pair of buttons 76 of the housing 12 inwardly, which will force the jaws 20 back to the undeployed position. This action will also withdraw the microneedle 12 from the skin, thereby allowing the injection system 10 to be disengaged. Figure 1c , Figure 2d and Figure 3c The injection system 10 is shown with the button 76 pressed back into the housing 12 and the jaws 20 returned to the undeployed state. The second phase 50 of each of the cams 44 facilitates this lateral displacement of the jaws 20 without requiring any relative longitudinal displacement between the housing 12 and the injection head 18.

[0080] Preferably, the injection system 10 is a disposable product that cannot be accidentally or otherwise reused, and therefore, it is desirable that the housing 12 cannot be displaced back to the undeployed state. Therefore, the actuator assembly 24 includes a locking element 78 that is operable to prevent the reversal of the relative longitudinal displacement between the housing 12 and the actuator assembly 24. The locking element 78 includes an elastically deformable catch 80 that is integrally formed with one of the side members 54 and protrudes laterally therefrom, and a corresponding tab 82 provided on the inner wall of the housing 12. The tab 82 is positioned to contact the catch 80 during the relative longitudinal displacement between the housing 12 and the actuator assembly 24, causing it to deflect and move past the catch. However, the catch 80 and the tab 82 are shaped to prevent movement past each other in the opposite direction, which is shown in the embodiment by defining a ratchet type arrangement. In this way, once the syringe 28 has been actuated and the medicament has been dispensed, the housing 12 is prevented from returning to the undeployed state. This is primarily for safety reasons.

[0081] Reference now Fig. 9 11 , there is shown an automated injection system according to an alternative embodiment of the present invention, generally indicated by 110. In this alternative embodiment, similar components are given similar reference numerals and perform similar functions unless otherwise specified. The injection system 110 includes a hollow housing 112 defining a handle, an injection head 118 located at a lower end 116 of the housing 112, and an actuator assembly 124 located within the housing 112. A syringe 128 of liquid medicine is fixed within the actuator assembly 124 in the same manner as previously described and is in fluid communication with one or more microneedles 122 protruding from a pair of jaws 120 of the injection head 118.

[0082] To achieve lateral relative displacement of the jaws 120 in response to relative longitudinal displacement of the housing 112 relative to the actuator assembly 124, each jaw 120 includes a cam 144 formed in an upper wall 146, which in this embodiment is located on the same side of the jaw 120 as the corresponding microneedle 122. The cam 144 includes only a first phase 148, which terminates in an aperture 148a, which is oriented to maintain the jaws 120 in a fixed relative position to allow injection of liquid through the microneedles 122. Unlike the first embodiment described above, the jaws 120 do not include any externally accessible release member to allow reversal of the lateral relative displacement of the jaws 120 to remove the microneedles 122 from the skin. Alternatively, the actuator assembly 124 includes a locking element in the form of a resiliently deformable latch 180 formed integrally with the actuator assembly 124 and protruding laterally therefrom, and a corresponding receptacle 182 provided in the wall of the housing 112. The tab 180 is positioned to contact a concave section of the housing 112 surrounding the receptacle 182 and thereby deflect inwardly, thereafter arriving and deflecting outwardly into the receptacle 182 at the end of the relative longitudinal displacement between the housing 112 and the actuator assembly 124. Once captured within the receptacle 182, the latch 180 prevents reversal of relative movement between the housing 112 and the actuator assembly 124. In this way, once the syringe 128 has been actuated and the medicament has been dispensed, the housing 112 is prevented from returning to the undeployed state. However, as Fig.10As can be clearly seen in the figure, the catch 180 is accessible from the outside, allowing the user to press the catch 180 out of the receptacle 182. At this point, the housing 112 is free to displace longitudinally along the actuator assembly 124, and if the user thus releases the downward pressure on the skin, the leaf spring 166 compressed between the closed upper end 114 of the housing 112 and the actuator assembly 124 will act to reverse the longitudinal displacement between the housing 112 and the actuator assembly 124, thereby helping to push the housing 112 upwardly away from the skin. This displacement will therefore reverse the lateral displacement of the pair of jaws 120 to pull the microneedle 122 out of the skin and allow the injection system 110 to be disengaged from the skin. The jaws 120 are each provided with a laterally extending guide rail 184 and a corresponding channel 186, so that when interlocked, the guide rail 184 of one jaw 120 is captured within the channel 186 of the other jaw 120. The rails 184 and channels 186 are sized to facilitate relative lateral displacement of the jaws 120 while providing interconnectivity and stability to the jaws 120 during operation.

[0083] In a modified form of the injection system 110, the plunger 160 of the syringe 128 may be provided with a laterally directed protrusion (not shown) adapted to engage an inwardly directed protrusion (not shown) on the deformable catch 180 at or near the end of the downward stroke of the plunger 128. This interaction causes the elastically deformable catch 180 to disengage from registration with the receptacle 182 in an automated manner. At this point, the housing 112 is free to displace longitudinally along the actuator assembly 124, and if the user thus releases the downward pressure on the skin, the leaf spring 166 compressed between the closed upper end 114 of the housing 112 and the actuator assembly 124 will act to reverse the longitudinal displacement between the housing 112 and the actuator assembly 124, thereby helping to push the housing 112 upwardly away from the skin.

[0084] Referring now to FIGS. 12 and 13 , there is shown an automated injection system, generally indicated by 210, according to yet another alternative embodiment of the present invention. In this alternative embodiment, similar components are given similar reference numerals and, unless otherwise noted, perform similar functions. The injection system 210 includes a hollow housing 212 defining a handle, an injection head 218 located at a lower end 216 of the housing 212, and an actuator assembly 224 located within the housing 212. The injection head 218 operates as previously described and includes a pair of jaws 220 that are laterally displaceable relative to each other in response to relative movement between the actuator assembly 224 and the housing 212. The actuator assembly 224 includes a fixed frame 226 that carries a syringe 228 as previously described, wherein a liquid medicament is dispensed from the jaws 220 in substantially the same manner as described with respect to the previous embodiment. However, unlike the previous embodiments, the frame 226 is fixed relative to the housing 212, and the actuator assembly 224 also includes a pair of actuator plates 224a, each of which is located or captured between the inner wall of the housing 212 and the frame 226 and can be longitudinally displaced relative to the housing 212. This relative longitudinal displacement is most clearly seen Fig.13b and Fig.13c , wherein the visible actuator plate 224a is in an undeployed state and a deployed state, respectively. The actuator plate 224a is fixed to the upper end 214 of the housing 212, and the upper end 214 can be telescopically displaced into the housing 212 to achieve a longitudinal displacement between the actuator assembly 224 and the dispensing head, thereby achieving a relative lateral displacement of the jaws 220.

[0085] Thus, the jaws 220 are each provided with a cam 244 formed therein, with a corresponding follower 252 protruding from a corresponding portion of the respective actuator plate 224a. It will therefore be appreciated that by pressing the upper end 214 into the housing 212, the actuator plate 224a will be longitudinally displaced relative to the housing 212, and as a result, the follower 252 will be driven to move downwardly along the cam 44 to effect relative lateral displacement of the jaws 220. The actuator assembly 224 includes a pair of guide members in the form of ramps 270 protruding from the inner wall of the upper end 214 of the housing 212 and being positioned to engage and displace the free end of the frame 226 in response to longitudinal displacement of the actuator assembly 224 relative to the housing 212, as previously described with respect to the first disclosed embodiment. As previously described, this will release the syringe biased by the spring to inject the liquid medicament. The free end of the frame 226 is preferably provided with a locking element in the form of a notch or groove 288 positioned and sized to receive the butt or upper end of a corresponding ramp 270 once the upper end 214 of the housing 112 has been fully depressed, thereby acting in a ratcheting manner to prevent reverse displacement of the upper end 214 and the actuator plate 224a. After the injection, the jaws 220 can be manually reversed relative to each other to allow the injection system 210 to be disengaged from the skin.

[0086] Reference now Figures 14 to 16 , shows an automated injection system according to a further alternative embodiment of the present invention, generally indicated by 310. In this alternative embodiment, similar components are given similar reference numerals and perform similar functions unless otherwise specified. Unlike the previous two embodiments, the injection system 310 is intended to be at least partially reusable and includes a hollow housing 312 in which an actuator assembly 324 is removably located, the actuator assembly carrying an injection head 318 that operates substantially as described above. A syringe 328 of liquid medicament is fixed within the actuator assembly 324 and is in fluid communication with one or more microneedles 322 protruding from a pair of jaws 320 of the injection head 318. However, the housing 312 is provided with one or more motors (not shown) and an associated power source (not shown), such as a battery or the like, which are operable to achieve lateral displacement of the jaws 320 to insert the microneedles 322 and depress the plunger of the syringe 328. As a result, the jaws 320 remain longitudinally fixed relative to the housing 312 and thus are only relatively longitudinally displaced relative to the actuator assembly 324 , and in particular the syringe 328 .

[0087] The housing 312 includes a first control or button 390 that can be depressed to activate a motor (not shown) to effect lateral displacement of the jaws 320 to insert the microneedle 322. The injection system 310 can then automatically depress the plunger of the syringe 328 using a suitable motor (not shown) again to inject the medicament. Once the medicament has been injected, the injection system 310 can automatically reverse the lateral displacement of the jaws 320, such as by operating one or more micro switches or sensors (not shown), to retract the microneedle 322 and allow the injection system 310 to be disengaged from the injection site. The injection system 310 preferably includes a second button 392 that, when depressed, allows the actuator assembly 324 and the injection head 318 to be released from the housing 312 to be replaced with the actuator 324 of the syringe 328 containing fresh medicament. The housing 312 may include embedded circuitry (not shown) and suitable components to facilitate wireless communication with a cell phone-based app, a cloud-based server, or both to automatically record injection performance and frequency, thereby enabling assessment of patient compliance and / or injection performance issues.

[0088] Reference now Figures 17 to 20 , an automated injection system according to another alternative embodiment of the present invention is shown, generally indicated by 410. In this embodiment, similar components are given similar reference numerals and perform similar functions unless otherwise specified. The injection system 410 includes a hollow housing 412 defining a handle, an injection head 418 located at the lower end 416 of the housing 412, and an actuator assembly (not shown) located within the housing 412. The injection head 418 is operated by the action of the first phase as previously described, and includes a pair of jaws 420 that can be laterally displaced relative to each other in response to relative movement between the actuator assembly (not shown) and the housing 412. The actuator assembly includes a fixed frame that carries a syringe as previously described, wherein the liquid medicament is dispensed from a microneedle protruding from the jaws 420 in substantially the same manner as described with respect to the previous embodiment.

[0089] Unlike the previous embodiments, the housing 412 includes an outer sleeve 412a that surrounds the main housing 412 and can be telescopically displaced a fixed distance in the longitudinal direction on the main housing. The shape and size of the sleeve 412a are designed to be grasped by a user to achieve operation of the injection system 410 as described above, and the sleeve extends over a considerable length of the main housing 412. The sleeve 412a is located and mechanically fixed in a first position relative to the housing 412, which is Fig.17 , Fig.18 and Fig.19 During the initial translational displacement of the pair of jaws 420, the sleeve 412a is fixed in this first or upper position, thereby inserting the microneedle into the skin, as shown in FIG. Fig.19 As shown. Once the medicament has been injected from the microneedle, the sleeve 412a is automatically mechanically released to permit longitudinal telescopic displacement to a second or lower position relative to the housing 412. This movement is performed in the direction toward the jaws 420 and continues for a fixed distance, and will therefore be affected by the user continuing to press the sleeve 412a against the skin, which will cause the sleeve 412a to move downward along the housing 412.

[0090] The injection system 410 includes a release member in the form of a pair of buttons 476, each of which is connected to or formed integrally with a corresponding one of the jaws 420 within the housing 412 and is located within the housing 412 until the jaws 420 are displaced laterally, at which time the release member is released. Fig.19 It can be seen that the buttons 476 protrude outwardly through the housing on opposite sides of the housing 412. Each button 476 has a tapered profile, the width of which increases in the direction toward the clamping jaw 420. Fig.19 It can be seen that in the raised or first position, the buttons 476 have been laterally moved out of the housing 412, with the thin upper end of each of the buttons 476 just below the lower edge or rim of the sleeve 412a. Then, as the sleeve 412a is displaced downwardly relative to the housing 412, its lower edge contacts the buttons 476, wherein the continued downward displacement of the sleeve 412a forces each of the buttons back to the inside of the housing 412, thereby causing the jaws 420 to be correspondingly displaced laterally or transversely back to the undeployed position. This will then disengage the microneedle from the skin and allow the injection system 410 to be removed and preferably discarded. The sleeve 412a is preferably mechanically prevented from returning to the upper or first position, thereby preventing reuse of the injection system 410.

[0091] Reference now Figure 21 to Figure 24 , an automated injection system according to another alternative embodiment of the present invention is shown, generally indicated by 510. In this embodiment, similar components are given similar reference numerals and perform similar functions unless otherwise specified. The injection system 510 includes a hollow housing 512 defining a handle, an injection head 518 located at the lower end 516 of the housing 512, and an actuator assembly 524 located within the housing 512. The injection head 518 includes a pair of jaws 520 that can be laterally displaced relative to each other in response to relative movement between the actuator assembly 524 and the housing 512. The actuator assembly 524 also houses a syringe 528 as previously described, wherein a liquid medicament is dispensed from a microneedle protruding from the jaws 520.

[0092] Unlike the previous embodiments, the actuator assembly 524 is tubular in form and is rotatable in response to relative longitudinal displacement between the housing 512 and the actuator assembly 524, which is achieved by the user placing the injection head 518 against the skin and pressing down using the housing 512 as a handle, as described above with reference to the previous embodiments. The housing 512 includes a pair of opposing catches 515 that protrude from the inner surface of the housing 512 and are captured in corresponding helical grooves 517 formed in the outer surface of the actuator assembly 524. Thus, the linear relative displacement is converted into a rotational displacement of the actuator assembly 524. It should be understood that the positions of the catches 515 and the helical grooves 517 can be reversed.

[0093] Although the dispensing head 518 is coupled to the actuator assembly 524, it does not rotate with the actuator assembly, but rather remains aligned with the housing as the dispensing head 518 moves through the open end 516 of the housing 512. The actuator assembly 524 includes a pair of longitudinally extending pins or followers 550 projecting from the lower end of the actuator assembly 524, each of which is seated in an elongated, substantially radially extending cam or slot 544 formed in a corresponding jaw 520. During downward pressure on the housing 512 by the user, the followers 550 are moved from the housing 512 together with the actuator assembly 524. Fig.23 The first or undeployed position is shown facing Fig.24 The relative movement between the follower 550 and the cam or slot 544 effects lateral displacement of the jaws 520 relative to each other. The actuator assembly 524 can be configured such that actuation of the first phase causes rotation in a first direction to displace the jaws 520 from an undeployed state to a deployed state, i.e., from Fig.23 The situation shown is shifted to Fig.24 The second phase of action can cause the actuator assembly 524 to rotate in the opposite direction to return the jaws to the undeployed state after dispensing the medicament, thereby allowing the injection system 510 to be removed from the skin.

[0094] Thus, the actuator assembly 524 is configured to convert the linear displacement of the housing 512 into a rotational displacement of the actuator assembly 524 relative to the housing 512. This rotational displacement can then be converted into a linear lateral displacement of the pair of jaws 520 to engage the microneedle in a first direction and disengage the microneedle in an opposite second direction. The rotational displacement of the actuator assembly 524 can also be used to achieve actuation of the syringe to dispense a medicament therefrom.

[0095] Thus, the injection system 10; 110; 210; 310; 410; 510 of the present invention provides a way to achieve intradermal injections that is simple, reliable, repeatable, and, due to the use of microneedles, substantially painless for the user.

Claims

1. An automated injection system, comprising: an elongated housing defining a handle; an actuator assembly disposed within the housing and longitudinally displaceable relative to the housing; an injection head mounted to the actuator assembly and projecting from an open lower end of the housing, the injection head comprising a pair of jaws displaceable relative to each other in a direction transverse to a longitudinal axis of the housing in response to relative longitudinal displacement between the housing and the actuator assembly, each jaw having one or more hollow microneedles projecting therefrom; a reservoir of a liquid contained within the housing, the reservoir being in fluid communication with one or more of the hollow microneedles; and a dispenser operable to pressurize the fluid in the reservoir in response to the relative longitudinal displacement between the housing and the actuator assembly to dispense the liquid from the one or more hollow microneedles.

2. An automated injection system as described in claim 1, wherein the reservoir is defined by a syringe, the syringe comprising a cylinder closed at one end by a piston, the piston being displaceable into the cylinder by the dispenser in order to pressurize the fluid.

3. An automated injection system as described in claim 2, wherein the dispenser includes a spring-biased plunger operatively associated with the piston.

4. The automated injection system of claim 3, wherein the plunger includes an abutment and the actuator assembly includes a latch member, the abutment being releasably retained against the latch member.

5. An automated injection system as described in claim 4, wherein the actuator assembly is operable to effect displacement of the latch member out of engagement with the abutment before or after completion of relative lateral displacement of the pair of jaws.

6. An automated injection system as described in claim 5, wherein the actuator assembly includes a biasing element, which is arranged to push the latch member out of engagement with the adjacent portion sequentially with the relative longitudinal displacement between the housing and the actuator assembly and / or after the relative longitudinal displacement.

7. An automated injection system as described in claim 6, wherein the biasing element includes a guide member, which is fixed to the housing and is capable of shifting against the latch member in response to the relative longitudinal displacement between the housing and the actuator assembly so as to push the latch member out of engagement with the adjacent portion.

8. An automated injection system as described in any of the preceding claims, wherein one of the jaws and the housing includes a cam and the other of the jaws and the housing includes a corresponding follower, the cam having a profile arranged to achieve the relative lateral displacement of the pair of jaws in response to the relative longitudinal displacement between the housing and the actuator assembly.

9. An automated injection system as described in claim 8, wherein each jaw includes a cam and the housing includes a corresponding pair of followers.

10. An automated injection system as claimed in any preceding claim, wherein the actuator is arranged for rotational displacement in response to relative linear displacement of the housing.

11. The automated injection system of claim 19, wherein the injection head is operable to convert the rotational displacement of the actuator assembly into the relative lateral displacement of the pair of jaws.

12. An automated injection system as claimed in any preceding claim, wherein the injection head comprises at least one release member manually operable to reverse the relative lateral displacement between the pair of jaws.

13. The automated injection system of claim 12, wherein the housing includes an aperture in a side wall through which the release member is accessible following the relative longitudinal displacement between the housing and the actuator assembly.

14. An automated injection system as described in claim 12 or 13, comprising a longitudinally displaceable sleeve on the housing, the longitudinally displaceable sleeve being displaceable into engagement with the at least one release member to reverse the relative lateral displacement between the pair of jaws.

15. An automated injection system as claimed in any preceding claim, comprising a locking element operable to prevent reversal of the relative longitudinal displacement between the housing and the actuator assembly.

16. An automated injection system as claimed in any preceding claim, wherein the actuator assembly comprises an elongated frame about which the housing is supported and within which the reservoir is housed, the injection head being mounted at one end of the frame.

17. The automated injection system of any preceding claim, wherein the hollow microneedle on each jaw is angled toward the hollow microneedle on the other jaw.

18. An automated injection system as claimed in any preceding claim, comprising a cap releasably securable about the lower end of the housing to enclose the injection head.

19. An automated injection system as claimed in any preceding claim, comprising a spring arranged to urge the housing longitudinally along the actuator assembly.

20. The automated injection system of claim 19, wherein the spring comprises a leaf spring disposed between the actuator assembly and the closed end of the housing.

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