Injection device and injection method

Abstract

The wearable medical fluid injection device includes an injection needle movable between a retracted position within the device housing and an injection position extending from the housing. An actuator moves the needle between the retracted and injection positions. A resilient bladder within the housing contains medical fluid for injection through the needle when in the injection position. A delivery termination member is disposed within the housing and biased to move from a first position toward a second position. When in the first position, the delivery termination member cooperates with the actuator to hold the injection needle in the injection position. When in the second position, the delivery termination member enables the actuator to move the injection needle to the retracted position and provides an indication of end of delivery. The injection device also includes an early lockout prevention system.

Description

[Background technology]

[0001] [Priority Claim] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 476,729, filed December 22, 2022, the contents of which are incorporated herein by reference in their entirety.

[0002] [Background technology] This application incorporates by reference the entire specification, drawings, and claims of US Pat. No. 9,925,333 as if they were repeated in full herein.

[0003] Vials are one of the pharmaceutical industry's preferred container closure systems due to their extensive clinical track record and long-term stability across a wide variety of drug products. Drugs, including biologics, are often first introduced commercially in standard containers like vials. Furthermore, the industry has invested heavily in equipment for aseptic vial filling. However, vials require the drug contained in them to be transferred from the vial to an injection device for patient administration. Newer container closure systems, such as prefilled syringes and cartridges, have been introduced, allowing the drug to be transferred directly from the syringe or cartridge to the patient. Injection devices, such as autoinjectors and pens, have been developed to utilize these new forms of container closure. Due to uncertainty regarding long-term drug stability and the large-scale manufacturing resources already in place, the pharmaceutical industry largely favors devices incorporating standard container closure systems, such as vials, prefilled syringes, and cartridges, over devices requiring custom forms of drug containment.

[0004] However, vials, prefilled syringes, and cartridges are not necessarily the optimal containers for medication delivery devices. This is especially true for delivery devices that deliver relatively large volumes of medication (2–20 cc) or high viscosities (greater than 15 cP). Vials, prefilled syringes, and cartridges are almost all glass cylinders, which impose design constraints on force and shape. Standard injection devices and autoinjectors are limited by the viscosity of the medications they can inject and the forces that can be applied to the glass container closure system. New injection devices, including insulin injection pumps, have been developed that use custom-made sealed containers, but these systems are very expensive, cannot generate high forces or pressures, and are usually reusable and / or refillable.

[0005] Due to factors such as stability and time to market, pharmaceuticals, including biologics, are often initially sold in lyophilized or powder form, or in concentrated liquid form. Such medications, packaged in vials in both liquid and powder formulations, may require significant preparation before administration. To facilitate administration of liquid formulations in vials, medications in vials are often packaged with an empty syringe and multiple needles for drawing from the vial and injecting into the patient. For powder formulations, a vial of additional diluent or solution may be provided to allow the powder medication to be reconstituted into an injectable solution.

[0006] The risks associated with preparing and administering these medication forms are significant. These include errors due to potential needlestick injuries during the reconstitution and administration process, improper mixing, and inaccurate administered doses or concentrations. This poses real challenges for both trained caregivers and patients preparing and receiving the medication. Similar risk issues may apply to the transfer of ready-to-inject medications, which require transfer from a vial to an injection device. This transfer involves removing the medication from the vial, measuring the appropriate dose, and injecting it into the patient using an injection device. Failure to completely transfer the entire vial volume necessitates overfilling the vial by approximately 25–30%, with the associated waste. Contamination of the injectable medication can occur due to contamination of the medication by nonsterile ambient air being injected into the vial or improper sterilization technique.

[0007] Thus, there continues to be a need for new and / or improved devices and methods for transferring, mixing, and injecting medication from a source vial or vials into a subject. Summary of the Invention

[0008] The following description is for purposes of example only and not limitation, and the present invention may be utilized in various devices, systems, and methods not illustrated below.

[0009] The present invention relates, in part, to a disposable, single-use device and method for, upon user action, preferably automatically mixing and / or transferring the injectable contents of one or more standard vials to an injection device, preferably simultaneously pressurizing the injection device for subsequent automatic injection into a subject. The contents of the vials can be any suitable injectable solution, and as used herein and in the claims, "injectable solution" includes, without limitation, any type of therapeutic or diagnostic drug, antibiotic, biologic, sedative, sterile water, and other injectable solution, alone or in combination with one or more other injectable solutions, regardless of whether they require reconstitution, concentration adjustment, or other processing prior to injection. While various features of the present subject matter may be described in the context of reconstituting powdered medications for injection, the devices and methods disclosed herein are not limited to that particular application and can also be used with liquid injectable solutions that are ready for injection and simply require transfer from a vial to an injection device. Furthermore, the disclosed devices and methods can be used with injectable solutions that do not require reconstitution or concentration adjustment but require mixing prior to injection (such as when mixing two liquid medications for combination drug therapy) and / or other injection applications.

[0010] The devices and methods described herein may be configured in any suitable detail, but are preferably configured to transfer the contents of a vial to an injection device. The device may also be configured to mix or process the contents of a vial that requires reconstitution or concentration adjustment during the transfer process. The device may also be configured to allow a user to select a dose volume for injection and may further include a lockout feature that requires such selection before the contents of the vial are allowed to communicate with the device or before transfer, mixing, or other processing begins. The device may also be configured to filter the contents to remove particulates or drug particles before transfer to the injection device and may include a sterile filter for filtering displacement air vented into the vial or vials. The device may also include a lockout to prevent a user from removing the injection device before drug transfer or from activating the injection device until the device is removed from the transfer device.

[0011] The present subject matter can include an on-body medical fluid injection device including a housing with a needle movable between a retracted position within the housing and an injection position extending from the housing. An actuator is associated with the needle to move the needle between the retracted and injection positions. A resilient bladder is disposed within the housing to receive medical fluid for injection through the needle when in the injection position. A delivery termination member is also disposed within the housing and is biased to move from a first position to a second position. The delivery termination member engages the bladder when the bladder is substantially filled with medical fluid, thereby preventing the delivery termination member from moving from the first position to the second position, and disengages from the bladder when the bladder is substantially emptied of medical fluid, allowing the delivery termination member to move from the first position to the second position. When in the first position, the delivery termination member cooperates with the actuator to hold the needle in the injection position, and when in the second position, the actuator moves the needle to the retracted position to provide an end-of-delivery indication. The injection device also includes a premature lockout prevention system including an engagement surface of the actuator and an engagement surface of the delivery termination member. The engagement surface of the actuator and the engagement surface of the delivery termination member are aligned when the delivery termination member is in a first position, and engagement between the engagement surface of the actuator and the engagement surface of the delivery termination member limits movement of the engagement surface of the actuator relative to the engagement surface of the delivery termination member. When the delivery termination member is in a second position, the engagement surface of the actuator and the engagement surface of the delivery termination member are misaligned, and the engagement surface of the delivery termination member does not impede movement of the engagement surface of the actuator.

[0012] While the present subject matter includes injection devices of any suitable detailed construction, injection devices that are particularly useful in combination with the devices herein are described in U.S. Patent Application No. 61 / 326,492, filed April 21, 2010; U.S. Patent Application No. 13 / 637,756, filed September 27, 2012; and U.S. Patent Application No. 61 / 704,922, filed September 24, 2012, all of which are incorporated herein by reference. As seen in these applications, the illustrated injection devices use an expandable member, such as a balloon, to automatically expel or inject medication when activated by a user. While long-term storage of medication in such a pressurized member presents design and manufacturing challenges, a particularly beneficial aspect of one embodiment of the present subject matter is that when the injection device is in an unpressurized state (e.g., the balloon is unfilled, unexpanded, and in a low-energy state), the injectable medication is retained in a standard, original vial or vials, extending its shelf life until injection is required. At that point, the injectable agent is preferably automatically transferred from the vial or vials to the injection device by a transfer device (including mixing, diluting, or other related processing, if necessary), which simultaneously fills the injection device (e.g., introducing the injectable agent under pressure, thereby expanding and pressurizing the expandable member or balloon) so that, upon user activation, the injection device is automatically ready to inject into a subject. In this application, the injectable agent remains within the injection device for a very limited period of time, such as a few seconds or minutes, thereby mitigating shelf-life concerns and design or material constraints associated with long-term drug storage.

[0013] According to another aspect of the present subject matter that can be employed in any suitable injection device, the expandable member (e.g., a balloon) can be elongated and configured to gradually contract from one end to the other during injection. While specific configurations vary, arranging the elongated expandable member in a generally planar or three-dimensional spiral configuration allows the expandable member to have a significant length and volume in a relatively compact configuration that can be applied and held against the subject's skin during injection. The injection device can be provided with an observation window that allows a user to observe the expandable member and discern the overall status of the injection by the amount of contraction, and / or the expandable member or observation window can be appropriately graduated to allow the user to determine the volume of injection that has been administered.

[0014] The vial holder, transfer device and injection device, and methods of use thereof, are separate aspects of the present subject matter, each having its own utility and may be claimed separately, but may also be configured and claimed in various combinations or subcombinations, such as a combination of a transfer device and an injection device, or a combination of a vial holder, transfer device and injection device, and / or methods of use thereof. [Brief explanation of the drawings]

[0015] Examples of the subject matter of this patent application are illustrated by way of illustration only and not by way of limitation in the accompanying drawings.

[0016] FIG. 1 is a perspective view of a single vial system including a single vial holder, transfer device and injection device system embodying the present invention.

[0017] FIG. 2 is a perspective view of a dual vial system including a dual vial holder, a transfer device, and an injection device system embodying the present invention.

[0018] FIG. 3 includes a perspective view of a single vial holder including a removable top, a cross-sectional view of a single vial holder including a removable top, and a perspective view of a single vial holder with the removable top and vial cap removed.

[0019] FIG. 4 includes a perspective view of the dual vial holder including the removable top and a cross-sectional view with the removable top and vial cap removed.

[0020] FIG. 5 is a cross-sectional view of FIG. 2 in the region of the vial holder, showing the position of the vial access member relative to the septum of the vial.

[0021] 6 is a cross-sectional view of FIG. 1 in the region of the vial holder showing the vial access member penetrating the septum of the vial.

[0022] FIG. 7 is a perspective view of the transfer device shown in FIG. 1, showing the vial holding portion and the injection device receiving area.

[0023] FIG. 8 is a close-up view of FIG. 5 showing the vial access member piercing the septum of the vial with a collapsible vial access member shield.

[0024] FIG. 9 is a schematic diagram of the dual-vial transfer system of FIG. 2, including a first vial, a second vial, a transfer device with a first variable pressure chamber and a second variable pressure chamber, and an injection device including a fluid path.

[0025] FIG. 10 is a cross-sectional view of FIG. 2 in the pre-launch position.

[0026] FIG. 11 is a schematic diagram of the single vial transfer system of FIG. 1 showing a drug vial, a transfer device with a first variable pressure chamber, and an injection device including a fluid pathway.

[0027] FIG. 12 is a cross-sectional view of FIG.

[0028] FIG. 13 is a schematic diagram of an alternative embodiment of the dual-vial transfer system of FIG. 2, including a first vial, a second vial, a transfer device with a first pressure chamber, and an injection device including a fluid path.

[0029] FIG. 14 is a schematic diagram of an alternative embodiment of the dual-vial transfer system of FIG. 2, including a first vial, a second vial, a transfer device with a first variable pressure chamber and a second variable pressure chamber, and an injection device including a fluid path.

[0030] FIG. 15 is a schematic diagram of an alternative embodiment of the dual vial transfer system of FIG. 2, including a first vial, a second vial, a transfer device with a first pressure chamber, a dual lumen connector, and an injection device including a fluid path.

[0031] FIG. 16 is a cross-sectional view of FIG.

[0032] FIG. 17 is a schematic diagram of an alternative embodiment of the single vial transfer system of FIG. 1, including a drug vial, a transfer device with a first variable pressure chamber, and an injection device including a fluid path with a check valve and a flow restrictor.

[0033] FIG. 18 is a cross-sectional view of FIG.

[0034] FIG. 19 is a cross-sectional view of FIG.

[0035] FIG. 20 is a perspective view of the injection device.

[0036] FIG. 21 is a top view of the filled injection device, showing the delivery indicator in a full state.

[0037] FIG. 22 is a top view of a filled injection device showing the delivery instructions empty.

[0038] FIG. 23 is a perspective view showing the underside of the injection device with the tape and fill port attached.

[0039] FIG. 24 is a perspective view showing the underside of the injection device with the tape removed, exposing the fill and administration ports.

[0040] FIG. 25 is a cross-sectional view of an injection device on a transfer device.

[0041] FIG. 26 is a perspective view of the injection device attached to the skin with the safety mechanism attached.

[0042] FIG. 27 is a perspective view of the injection device attached to the skin with the safety removed and the button in the up position before firing.

[0043] FIG. 28 is a perspective view of the injection device attached to the skin with the safety removed and the button pressed in the firing position.

[0044] FIG. 29 is a cross-sectional view of the injection device attached to the skin with the button in the up position before firing.

[0045] FIG. 30 is a cross-sectional view of the injection device attached to the skin in the first firing state with the button pressed.

[0046] FIG. 31 is a cross-sectional view of the injection device attached to the skin in a dispensing position with the button depressed.

[0047] FIG. 32 is a cross-sectional view of the injection device attached to the skin, showing the end-of-delivery indicator in an unactivated state.

[0048] FIG. 33 is a cross-sectional view of the injection device attached to the skin, showing the end-of-delivery indicator activated.

[0049] FIG. 34 is a cross-sectional view of the injection device attached to the skin in the post-fire state with the button locked.

[0050] FIG. 35 is a perspective view of the injection device removed from the skin with the bandage remaining on the skin.

[0051] FIG. 36 is a perspective view of the injection device in a filled state with the upper housing removed.

[0052] FIG. 37 is a top view of the injection device shown in FIG.

[0053] FIG. 38 is a perspective view of the injection device in an empty state with the upper housing removed.

[0054] FIG. 39 is a top view of the injection device shown in FIG.

[0055] FIG. 40 is a perspective view of the packaged single vial system.

[0056] FIG. 41 is a perspective view of the single vial system with the package open.

[0057] FIG. 42 is a perspective view of a single vial system in a package with the lid removed to expose the contents of the package.

[0058] FIG. 43 is a perspective view of a single vial system with the vial holder removed from the packaging and the vial cap removed.

[0059] FIG. 44 is a perspective view of a single vial system with the vial holder fully inserted into the transfer device.

[0060] FIG. 45 is a perspective view of a dual vial system with a vial holder attached.

[0061] FIG. 46 is a top view of FIG. 45 showing the volume control in a preset state.

[0062] FIG. 47 is a top view of FIG. 45, showing the volume control in the set state.

[0063] FIG. 48 is a perspective view of the dual vial system with the volume control removed and the vial holder pushed into the transfer device to begin the mixing and transfer process.

[0064] FIG. 49 is a perspective view of the dual vial system after the mixing and transfer process, filling of the syringe device, and disengagement of the syringe device removal interlock have been completed.

[0065] FIG. 50 is a perspective view of a single vial system with the injection device filled and removed from the packaging.

[0066] FIG. 51 is a perspective view of the injection device placed on the skin with the safety device in place.

[0067] FIG. 52 is a perspective view of the injection device placed on the skin and with the safety mechanism removed.

[0068] FIG. 53 is a perspective view of the injection device placed on the skin and the button pressed to initiate the injection.

[0069] FIG. 54 is a perspective view of the injection device removed from the skin after injection with the button in the locked position and the bandage remaining on the skin.

[0070] FIG. 55 is a perspective view of an injection device embodying the present invention.

[0071] FIG. 56 is a cross-sectional view of FIG. 55 showing the injection device with the button in the first position.

[0072] Figure 57 is a diagram showing the four stages of needle penetration into tissue: (a) non-contact, (b) boundary displacement, (c) tip insertion, and (d) shaft insertion (van Gerwen, D.J., Experimental Needle-Tissue Interaction, Delft University of Technology, PhD Thesis, 2013, ISBN978-94-6186-238-9, p. 1).

[0073] FIG. 58 is a cross-sectional view of FIG. 55 showing the injection device with the button in the second or dispensing position.

[0074] FIG. 59 is a perspective view of a single vial transfer system fitted with a drug vial and injection device embodying the present invention.

[0075] FIG. 60 is a cross-sectional view of FIG. 59 illustrating an embodiment of the vial retaining area showing the drug vial, vial access member, and extension member in a lowered position.

[0076] FIG. 61 is a cross-sectional view of FIG. 59 showing the vial retaining area showing the drug vial, vial access member, and extension member in the up position.

[0077] FIG. 62 is a cross-sectional view of FIG. 59 with the box and tray removed to show aspects of the pressure chamber and fluid passages.

[0078] FIG. 63 is a cross-sectional view of FIG. 59 showing one embodiment of the vial retaining area showing the drug vial, vial access member and exit opening.

[0079] FIG. 64 is a cross-sectional view of a single vial system including a single vial holder, transfer device, and injection device system.

[0080] FIG. 65 is a schematic diagram of an alternative embodiment of the single vial transfer system of FIG. 64, comprising a drug vial, a transfer device with a first variable pressure chamber, and an injection device including a fluid path with a check valve and a flow restrictor.

[0081] FIG. 66 is a cross-sectional view of FIG. 55 showing the adhesive / device interface and the adhesive / skin interface.

[0082] FIG. 67 is a perspective view of the bottom of the injection device showing the different zones of adhesive.

[0083] FIG. 68 is a cross-sectional view of FIG. 55 showing bulging tissue on the device with permanently attached adhesive.

[0084] FIG. 69 is a cross-sectional view of FIG. 55 showing bulging tissue on a device with adhesive applied in multiple zones.

[0085] FIG. 70 is a perspective view of the top of an alternative injection device.

[0086] FIG. 71 is a cross-sectional view of FIG. 70 showing the disconnect sensor disengaged and the needle locked in the dispense position.

[0087] FIG. 72 is a cross-sectional view of FIG. 70 showing the disconnect sensor engaged and the needle and button retracted to the post-fire position.

[0088] FIG. 73 is a cross-sectional view of FIG. 55 showing the injection device with the button in the first or pause position.

[0089] FIG. 74 is a cross-sectional view of FIG. 55 showing the injection device with the button in the second or dispensing position.

[0090] FIG. 75 is a cross-sectional view of FIG. 55 showing the injection device with the needle retracted and the button in the up or pre-fire position.

[0091] FIG. 76 is a cross-sectional view of FIG. 55 showing the injection device with the button in the second or dispensing position.

[0092] FIG. 77 is a perspective view of a single vial transfer device.

[0093] FIG. 78 is a perspective view of the injection device.

[0094] FIG. 79 is a cross-sectional view of FIG. 78 showing the injection device with the button in the second or dispensing position.

[0095] FIG. 80 is a schematic diagram of an alternative embodiment of the single vial transfer system of FIG. 64, comprising a drug vial, a transfer device with a first variable pressure chamber, and an injection device including a fluid path with a check valve and a flow restrictor.

[0096] FIG. 81 is a cross-sectional view of FIG. 77 showing the vial receiving area.

[0097] FIG. 82 is a schematic diagram of a dual-vial transfer system including a first vial, a second vial, a transfer device with a first variable pressure chamber and a second variable pressure chamber, and an injection device including a fluid path.

[0098] FIG. 83 is a perspective view of the injection device with the safety sleeve attached.

[0099] FIG. 84 is a cross-sectional view of FIG. 55 showing the injection device with the button in the second or dispensing position.

[0100] FIG. 85 is a cross-sectional view of FIG. 59 showing one embodiment of the vial holder area showing the drug vial, vial access member, and angle sensor in the open position.

[0101] FIG. 86 is a cross-sectional view of FIG. 59 showing the vial holder area showing the drug vial, vial access member, and angle sensor in the closed position.

[0102] FIG. 87 is a schematic diagram of an alternative embodiment of a single vial transfer system comprising a drug vial, a transfer device with a first variable pressure chamber, and an injection device including a fluid path with a check valve.

[0103] FIG. 88A is a partial cross-sectional view of an injection device featuring an alternative embodiment of an automatic needle retraction mechanism with the elastic bladder filled with medication and the button in the start or pre-fire position.

[0104] FIG. 88B is a partial cross-sectional view of the injection device of FIG. 88A, showing the elastic bladder empty or nearly empty of medication and the button in the dispensing position.

[0105] FIG. 89 is a perspective view of the injection device of FIGS. 88A and 88B in a starting or pre-fire configuration with the safety sleeve deployed.

[0106] FIG. 90 is a perspective view of the injection device of FIG. 89, showing the retainer, elastic bladder, button cap, and button.

[0107] 91 is a perspective view of a leaf spring of the injection device of FIG. 89. FIG.

[0108] 92 is a perspective view of the button, delivery termination member, and leaf spring of the injection device of FIG. 89. FIG.

[0109] 93 is a perspective view of the button, delivery termination member, leaf spring, return spring and cannula of the injection device of FIG. 89. FIG.

[0110] 94 is another perspective view of the button and leaf spring of the injection device of FIG. 89. FIG.

[0111] 95 is another perspective view of the button, delivery termination member, and flat spring of the injection device of FIG. 89. FIG.

[0112] FIG. 96 is a perspective view of the injection device of FIG. 89 in a dispensing configuration.

[0113] 97 is a perspective view of the button and leaf spring of the injection device of FIG. 96. FIG.

[0114] 98 is a perspective view of the button, delivery termination member, leaf spring, return spring and cannula of the injection device of FIG. 96. FIG.

[0115] 99 is a perspective view of the button, leaf spring, and cannula of the injection device of FIG. 96. FIG.

[0116] FIG. 100 is a perspective view of the injection device of FIG. 89 in a suspended configuration.

[0117] 101 is a perspective view of the button, delivery termination member, and cannula of the injection device of FIG. 100. FIG.

[0118] 102 is a perspective view of the button and leaf spring of the injection device of FIG. 100. FIG.

[0119] FIG. 103 is a perspective view of the injection device of FIG. 89 in a post-injection lockout configuration.

[0120] FIG. 104 is a perspective view of the button and leaf spring of the injection device of FIG.

[0121] FIG. 105 is a state diagram illustrating how the injection device of FIGS. 88A-104 operates in response to various user inputs.

[0122] FIG. 106A is a partial cross-sectional view of an injection device featuring an alternative embodiment of an automatic needle retraction mechanism with the elastic bladder filled (not shown) and the button in the start or pre-fire position.

[0123] FIG. 106B is a partial cross-sectional view of the injection device of FIG. 106A with the elastic bladder filled and the button in the injection or dispensing position.

[0124] FIG. 106C is a partial cross-sectional view of the injection device of FIGS. 106A and 106B after dispensing or injection is completed with the elastic bladder empty or nearly empty and the button still in the injecting or dispensing position.

[0125] FIG. 106D is a partial cross-sectional view of the injection device of FIGS. 106A-106C after completion of dispensing or injection with the elastic bladder empty or nearly empty and the button moving toward the post-fire lockout position.

[0126] FIG. 107A is a partial cross-sectional view of an injection device featuring another alternative embodiment of an automatic needle retraction mechanism with the elastic bladder empty and the button in the start or pre-fire position.

[0127] FIG. 107B is a partial cross-sectional view of the injection device of FIG. 105A with the elastic bladder filled and the button in the dispensing position. DETAILED DESCRIPTION OF THE INVENTION

[0128] 1 and 2, as described in more detail below, a disposable, single-use, single-vial transfer and injection system 1 shown in FIG. 1 may include a single-vial holder 2, a transfer device 3, and an injection device 7. A disposable, single-use, dual-vial mixing, transfer, and injection system 4 shown in FIG. 2 may be comprised of a dual-vial holder 5, a transfer device 6, and an injection device 7. As previously mentioned, each of these aspects has distinct utility and may be claimed individually and / or in combination or subcombinations.

[0129] Referring to Figures 3 and 4, the illustrated single vial holder 2 includes a housing 8 including a side wall 9, an end wall 10, and an opening or observation window 11. Alternatively, the material of the vial holder 2 may be transparent to allow visualization of the contents of the vial 12. The housing 8 is shaped to define at least one or more vial-receiving cavities 13 or zones 13 for securely holding a vial 12, as shown in Figure 4. The cavities 13 within the vial holder 5 can be sized to accept standard injection vials 12 of different sizes, such as from 1 mL to 30 mL. The vials 12 can be the same size or different and can contain any desired injection drug 14. In the dual vial holder 5 shown in Figure 4, the vials may include one vial 15 of a powder, lyophilized, or liquid drug and one vial 16 of a liquid or diluent. Vial-retaining portion 5 may have vials pre-packaged and assembled, for example, by a pharmaceutical manufacturer, or vials may be inserted into vial-retaining portion 5 by an end user or a medical professional, such as a pharmacist or nurse. Vial-retaining portion 5 may be provided with appropriate markings and / or features to allow particular vials to be incorporated only into particular cavities 13. For example, a powdered drug vial 15 may be inserted into a particular cavity 13 of vial-retaining portion 5, and a diluent vial 16 may be inserted into another cavity 13 of vial-retaining portion 5. An opening or observation window 11 in vial-retaining portion 5 allows direct observation of the vial contents 14.

[0130] 3 and 4, as a further alternative, the vial holder 5 may be an assembly of individual vial holders 2, each holding a single vial 12. For example, an injection manufacturer may pre-assemble vials 12 into individual vial holders 2, and then, as needed, combine them with the vial holder 2 of another vial 12 at the time of injection. For example, a pharmaceutical manufacturer may provide a lyophilized drug 15 in their vial holder 2 and a diluent 16, such as sterile water or saline, in another vial holder 2. A user or medical professional may then combine the individual vial holders 2, as needed, to form a vial holder assembly 5 for connection to a transfer device 6, shown in FIG. 2.

[0131] Returning to FIG. 3 , vial holder 2 may include a removable cover 17 that normally covers and protects the end of vial 18 during transport and storage. A typical standard commercially available vial 12 is provided with a pierceable septum 19 in the neck of the vial for access to the vial's contents 14, which is covered by a removable vial cap or closure 20. Removable cover 17 may be configured to engage with vial cap 20 such that removal of the cover simultaneously removes vial cap 20, exposing vial septum 19 and allowing access to contents 14 after a disinfectant wipe of septum 19 is deemed necessary by the user. Vial holder 2 may submerge vial 12 therein, such that after vial cap 20 is removed by cover 17, pierceable septum 19 is submerged within vial holder 2 to reduce the possibility of user contamination before inserting vial holder 2 into transfer device 3, as shown in FIG. 1 . This system is applicable to both single vial holder 2 and dual vial holder 5.

[0132] 3, vial holder 2 may include an interlock 27 to prevent vial 12 from being removed after it has been inserted into vial holder 2. This prevents vial 12 from being dropped or accidentally removed during handling.

[0133] 5, the vial holder 5 may be assembled to the transfer device 6 with the vial caps removed and vials 15, 16 installed in the vial holder 5 by the device manufacturer. The exposed vial septum 19 is held adjacent to the vial access members 21, 52 prior to activation. This configuration improves convenience by eliminating the need for the user to remove the vial caps, wipe the vial tops 19, and assemble the vial holder 5 to the transfer device 6 before using the system 4.

[0134] 6, the vial holder 2 may be packaged separately from the transfer device 3. In this case, the user removes the vial cap along with the removable cover 17, wipes the top 19 of the vial (if necessary), and assembles the vial holder 2 into the transfer device 3. As shown in FIG. 6, the vial holder 2 may include a lockout feature 22 that interacts with the transfer device 3 to prevent the vial holder 2 from being accidentally pulled out of the transfer device 3 after activation by the user.

[0135] Referring to FIG. 5, the vial holder 5 is preferably incorporated into the transfer device 6, with the vials 15, 16 positioned in an upside-down vertical position. This allows the liquid 23 in the vial to be in direct communication with the vial access members 21, 52 after the vial holder 5 is inserted. This forces air 24 to be forced out the top of the vial in this orientation. After removing the vial cap and before inserting the vial holder 5, the exposed vial septum 19 can be recessed within the vial holder 5 to prevent contamination and inadvertent contact, as shown in FIG. 4. This configuration is applicable to both single-vial holder and dual-vial holder configurations.

[0136] 6, vial holder 2 is preferably mechanically configured with insertion feature 25 of transfer device 3 to operate like an on / off switch, i.e., to have only two states, open and closed, like a light switch. This prevents a user from pushing vial holder 2 partway into transfer device 3 without vial access member 21 piercing septum 19, allowing communication between contents 14 of vial 12 and transfer device 3. Additionally, vial holder 2 interfaces with interlock 26 within transfer device 3 to lock vial holder 2 in a closed position after vial holder 2 is fully inserted, preventing vial holder 2 from being removed from transfer device 3 after insertion.

[0137] 7, the transfer device 3 includes an outer housing 28 defining a vial holder docking area or first receiving station 29 and an injection device docking station or second receiving station 30 (for a removable injection device). In the illustrated configuration, the vial holder docking station 29 and the injection device docking station 30 are located at opposite ends of the transfer device housing 28.

[0138] Referring to FIG. 7 , the transfer device 3 may have an outer housing 28 integrated into the system's packaging 31. The outer packaging 31 may essentially form the bottom and side walls of the transfer device's outer housing 28. All operational steps for using the system up to the point of removing the injection device may be performed within this packaging 31. This reduces costs and improves ease of use for the user. Additionally, incorporating the entire transfer device 3 into the packaging 31 eliminates user error that may occur if the user needs to remove the transfer device 3 from the packaging 31. The packaging 31 may include a plastic container or tray that houses the system. Additionally, the packaging 31 may include everything within a shipping carton 32 that receives the entire system.

[0139] Referring to FIG. 7, the transfer device 3 includes a vial holder docking area 29 that may include an elongated vial access member or piercing member 21. The access member or piercing member 21 may be configured as a sharp or blunt cannula or needle. Referring to FIG. 8, the vial holder 5 with the attached vial 12 is shown inserted into the vial docking station 29, allowing the vial access member 21 to pierce the vial septum 19 and access the contents 14 of the vial 12. The vial access member 21 may include a foldable closure 33 to maintain sterility of the vial access member 21 and the fluid pathway prior to activation. The foldable closure 33 may also be attached to and seal against the exterior of the vial 12 to maintain sterility prior to activation.

[0140] 8 , the vial access member 21 of the transfer device 3 may include a multi-lumen tube 34 that communicates with the internal fluid pathway 35 of the transfer device 3. The vial access member 21 preferably includes one inlet tube 36 that allows air or fluid to enter the vial 12 and one outlet tube 37 that allows air or fluid to exit the vial 12. The inlet tube 36 and outlet tube 37 may be separate and distinct and communicate with different fluid pathways within the transfer device 3. Because the vial 12 is oriented vertically in an upside-down position, the lumen opening 38 of the vial access member 21 may be positioned such that the inlet tube opening 36 is above the outlet tube opening 37. This orientation allows pressurized air or liquid to be introduced through the upper inlet tube 36 and the vial contents 14 to be expelled through the lower outlet tube 37. Additionally, the outlet opening 37 can be positioned near the bottom of the vial 12, adjacent the septum 19, such that the entire contents 14 of the vial 12 enter the outlet port 37 and are removed from the vial 12.

[0141] 9 and 10, transfer device 6 is configured to perform all of the steps necessary to transfer and (if necessary) reconstitute the injectable agent 14 contained in vials 15, 16, and automatically transfer the mixture to injection device 7, preferably after a user has initiated the process. Transfer device 6 is configured to direct diluent from diluent vial 16 to injectable powder vial 15 and direct injectable agent 14 through transfer device 6 to injection device 7, and preferably includes a propulsion system or systems, such as an electrically (e.g., battery-powered) or mechanically (e.g., spring-powered) actuated pump.

[0142] 9 and 10, the transfer device 6 may also include an arrangement of internal fluid paths 35 necessary to transfer, reconstitute, mix, dilute, or otherwise process the injectable medication 14 from the vials 15, 16 in the vial holder 5 to the injection device 7. The fluid paths 35 may include flexible or rigid conduits or tubes. These fluid paths 35 may also include check valves, filters, flow restrictors, or other means 40 for directing the medication from the vials 15, 16 through the transfer device 6 to the injection device 7.

[0143] 9 and 10, the transfer device 6 may include a variable volume pressure chamber or cylinder having a movable spring-loaded piston therein and in direct communication with the internal fluid pathway 35. The volume of each variable volume chamber may be defined by the diameter of the chamber and the position of the piston within the chamber. The initial volume of the first pressure chamber 41 of the transfer device 6 is preferably set by the manufacturer to a range of 1 to 30 mL. The initial contents of the first pressure chamber 41 preferably include air 45. The piston 43 may be driven by a compression spring 44 within the first pressure chamber 41, the volume of which is defined and set by the manufacturer. The spring-loaded piston 43 may be appropriately sized and configured to generate a static air pressure of 1 to 50 psi within the first pressure chamber 41. The volume of the air 45 is determined by the diameter of the chamber 41 and the position of the stroke of the piston 43 during operation. This pressure is determined by the relative volume of air 45 displaced by the piston 43 and the force exerted by the spring 44. In other words, the force exerted by the spring 44 multiplied by the area of ​​the piston 43 within the chamber 41 determines the static pressure within the chamber 41. The force exerted by the spring 44 at the beginning of its fixed height or stroke can be much higher than the force exerted by the spring 44 at the end of its travel. The spring 44 can be appropriately sized to control the rate at which air 45 is exhausted from the pressure chamber 41, and thus the rate at which fluid is transferred in the transfer device 6. The first pressure chamber 41 is preferably configured to exhaust all of the air 45 within the first pressure chamber 41. Alternatively, a flow restrictor 55 in the output path 35 of the pressure chamber 41 can be used to control the rate at which air 45 is exhausted from the pressure chamber 41.

[0144] 9 and 10, the chamber volume of the second pressure chamber 42 can be set by the manufacturer. Alternatively, the filled chamber volume of the second pressure chamber 42 can be set by the user during use using a dose selector or volume control 48, ranging from 0.5 to 30 mL. The spring-loaded piston 46 within the second pressure chamber 42 can be sized and configured to generate a pressure of 1 to 200 psi within the second pressure chamber 42. The dose selector or volume control 48 allows the user to select a predetermined dose to be injected by the injection device 7 by setting the fill volume of the chamber 42. The dose selector 48 can be configured in any suitable manner. The dose selector 48 can be directly coupled to a pressure plunger assembly chamber 93 that is movable within the pressure chamber 42. A trigger 49 within the pressure plunger assembly 93 releases the piston 46 within the second pressure chamber 42 when the piston reaches a position corresponding to the fill volume setting. The user selects the desired dose position within the second pressure chamber 42 by moving the dose selector 48 to position the pressure chamber plunger assembly 93 so that the filled chamber volume equals the desired injection dose. Alternatively, the position of the pressure plunger assembly 93 is already set by the manufacturer according to the dose to be delivered, and the user can operate the device without making any dose adjustments.

[0145] 9 and 10, a transfer device 6 for a dual vial system 4 that enables mixing and transfer includes a vial holder 5 with a first vial 16 and a second vial 15, a first variable volume pressure chamber 41, a second variable volume dosing pressure chamber 42, a fluid path 35, and a check valve 40 for delivering air from the first pressure chamber 41 to the first vial 16, delivering the contents 23 of the first vial 16 to the second vial 15, delivering the resulting mixture 14 in the second vial 15 to the second pressure chamber 42, and then transferring the mixture 14 in the second vial 15 to an injection device 7.

[0146] Referring to FIG. 8, when the vial holder 5 is fully inserted into the transfer device 6 and the vial access member 21 is subsequently introduced by the user through the septum 19 into the vial chamber 12, the pressure chamber trigger 50 shown in FIG. 10 is released.

[0147] 9 and 10 , when trigger 50 is released, first pressure chamber spring 44 is released, allowing first pressure chamber piston 43 to advance within first pressure chamber 41, forcing air 45 within first pressure chamber 41 through inlet tube 36 of first vial access member 21, through internal passage 35 of transfer device 6, and into first vial 16. As more air 45 is forced out of first pressure chamber 41 through inlet tube 36 and into first vial 16, the air rises to the top of first vial 16 because first vial 16 is positioned vertically within vial holder 5. As the air pressure within first vial 16 increases, fluid 23 within vial 16 is expelled through outlet tube 37 of first vial access member 21 and inlet tube 51 of second vial access member 52. Fluid 23 entering second vial 15 from first vial 16 mixes with contents 54 of second vial 15, which may contain a liquid or powdered medicament, and is expelled through outlet tube 53 of second vial access member 52 into second pressure chamber 42. Similarly, in the reconstitution configuration, advancement plunger 43 in first pressure chamber 41 continues to push the mixture of first fluid 23 and air 45 through first vial 16 and into second vial 15. As air pressure increases above second vial 15, reconstitution mixture 14 at the bottom of second vial 15 is expelled into second pressure chamber 42. A "pop-off" or check valve 40 or other type of valve may be provided in outlet tube 53 of second vial access member 52 to ensure that all of contents 23 of first vial 16 enters second vial 15 before contents 14 of second vial 15 are expelled into second pressure chamber 42. The valve will not open until the pressure corresponding to the plunger 43 has forced substantially all of the air 45 out of the first pressure chamber 41. This ensures that the contents 54 of the second vial 15 are thoroughly mixed with the contents 23 of the first vial 16 before the mixture 14 exits the second vial 15 and enters the second pressure chamber 42. Alternatively, a flow restrictor 55 can be used in the fluid path 35 to slow the transfer and allow for longer mixing times.

[0148] 9 and 10, after reconstitution, the injectable medication 14 flows from the second vial 15 into the second pressure chamber 42, filling the chamber 42 to the extent permitted by the position of the piston 46 selected by the user or manufacturer using the dose indicator 48, i.e., the desired dose. Once the desired volume of the second pressure chamber 42 is achieved, the second pressure chamber trigger 49 releases the spring 47, pushing the piston 46 forward and expelling the selected dose of injectable medication 14 under pressure into the injection device 7. To account for fluid loss in the internal passageway 35 of the transfer device 6, a calibration of the dose displayed on the dose selector 48 with the dose actually received by the user may be necessary. The injection device 7 is now full and ready to be removed from the transfer device 6.

[0149] 11 and 12, an alternative transfer device 3 within a single vial system 1 is provided that does not perform mixing and simply transfers fluid 14 from a single vial 15 to an injection device 7. This alternative transfer device 3 includes a vial holder 2 with a single vial 15, a variable volume pressure chamber 56, a fluid pathway 35, and a check valve 40 that directs contents 14 from the vial 15 to the injection device 7. An inlet tube 36 of the vial access member 21 is vented to the environment 57, allowing air 58 to enter the vial 1. An outlet tube 37 of the vial access member 21 is connected to the pressure chamber 56.

[0150] 11 and 12, when the user fully inserts the vial holder 2 into the transfer device 3, the vial access member 21 is introduced through the septum 19 of the vial 15, providing access to the contents 14 of the vial 15. This causes the release of the pressure chamber trigger 59. The pressure release trigger 59 releases a plunger 60 within the pressure chamber 56, which is connected to a retraction spring 61. The retraction spring 61 forces the plunger 60 to retract, drawing fluid 14 from the vial 15 and filling the pressure chamber 56. The specified amount of fluid 14 drawn by the chamber 56 can be set by the manufacturer by limiting the retraction of the plunger 60. Additionally, the chamber 56 can be configured to withdraw all of the fluid 14 from the vial 15 by retracting the plunger 60 to its maximum travel distance. When plunger 60 reaches a set position within pressure chamber 56, plunger 60 interacts with dispense trigger 62, releasing dispense spring 63 to force liquid 14 out of pressure chamber 56 and into injection device 7. Check valve 40 can be used to prevent fluid 14 from returning to vial 15.

[0151] Referring to FIG. 13 , an alternative transfer device 6 for a dual vial system 4 that enables mixing and transfer includes a vial holder 5 with a first vial 16 and a second vial 15, a variable volume pressure chamber 56, a fluid pathway 35, and a check valve 40 that directs the contents 23 of the first vial 16 to the second vial 15 and the resulting mixture 14 into the pressure chamber 56. The mixture 14 is then returned to the second vial 15 and then transferred to the injection device 7. In this embodiment, the inlet tube 36 of the first vial access member 21 is vented to the environment 57, allowing air 58 to enter the vial 16. The outlet tube 37 of the first vial access member 21 is connected to the inlet tube 51 of the second vial access member 52. The outlet tube 53 of the second vial access member 52 is connected to the variable volume pressure chamber 56. Fluid pathway 35 includes a check valve 40 disposed between first vial access member 21 , second vial access member 52 , and injection device 7 .

[0152] Referring to FIG. 13 , when a user fully inserts the vial holder 5 into the transfer device 6, the vial access members 21, 52 are introduced through the septums 19 of the vials 15, 16, allowing access to the contents 23, 54 of each vial 15, 16. This also initiates the release of the pressure chamber trigger. The pressure chamber trigger releases a plunger 60 connected to a retraction spring within the pressure chamber 56. The retraction spring retracts the plunger 60, drawing fluid 23 from the first vial 16 and filling the second vial 15. This filling also mixes the fluid 23 from the first vial 16 with the contents 54 of the second vial 15. The resulting mixture 14 from the second vial 15 fills the pressure chamber 56 until all of the fluid 23 has been removed from the first vial 16. The rate at which the first vial 16 fills the second vial 15 can be controlled by a check valve 40 or a flow restrictor 55. The amount of fluid 23 withdrawn from the first vial 16 can be set within the chamber 56 by the manufacturer. When the plunger 60 within the chamber 56 reaches a set position within the pressure chamber 56, the plunger 60 interacts with the dispense trigger, releasing the dispense spring and forcing the liquid 14 from the pressure chamber 56 back into the second vial 15. This has the advantage of allowing further mixing of the fluid 23 from the first vial 16 with the contents 14 of the second vial 15. Once all of the fluid 14 from the chamber 56 has been returned to the second vial 15, the solution 14 is transferred to the injection device 7. The volume of the pressure chamber 56 can be set to be larger than the total fluid volume so that additional air 58 is drawn into the pressure chamber 56. This additional air 58 helps ensure that all of the liquid 14 that may have remained in the fluid path 35 is transferred to the injection device 7. A check valve 40 may be used anywhere in the fluid path 35 to prevent the fluid 14 from returning to the first vial 16 while transferring the mixture 14 from the second vial 15 to the injection device 7. A flow restrictor 55 may be used anywhere in the fluid path 35 to control the amount of mixing time in the second vial 15 before transferring the mixture 14 to the injection device 7.

[0153] 14, an alternative transfer device 6 for a dual vial system 4 that enables mixing and transfer includes a vial holder 5 with a first vial 16 and a second vial 15, a first variable volume pressure chamber 56, a second variable volume pressure chamber 42, a fluid path 35, and a check valve 40 that directs the contents 23 of the first vial 16 to the second vial 15 and the resulting mixture 14 to the pressure chamber 56. The mixture 14 is transferred from the first pressure chamber 56 to the second pressure chamber 42 and then to the injection device 7. In this embodiment, the inlet tube 36 of the first vial access member 21 is vented to the environment 57, allowing air 58 to enter the vial 16. The outlet tube 37 of the first vial access member 21 is connected to the inlet tube 51 of the second vial access member 52. An outlet tube 53 of the second vial access member 52 is connected to a first variable volume pressure chamber 56. A fluid path 35 including a check valve 40 also exists between the first vial access member 21, the second vial access member 52, and the second pressure chamber 42 and the injection device 7.

[0154] Referring to FIG. 14 , when a user fully inserts the vial holder 5 into the transfer device 6, the vial access members 21, 52 are introduced through the septums 19 of the vials 15, 16, allowing access to the contents 23, 54 of each vial 15, 16. This also initiates the release of the pressure chamber trigger. The pressure chamber trigger releases a plunger 60 connected to a retraction spring within the pressure chamber 56. The retraction spring retracts the plunger 60, drawing fluid 23 from the first vial 16 and filling the second vial 15. This filling also mixes the fluid 23 from the first vial 16 with the contents 54 of the second vial 15. The resulting mixture 14 from the second vial 15 fills the pressure chamber 56 until all of the fluid 23 has been removed from the first vial 16. The rate at which the first vial 16 fills the second vial 15 can be controlled by a check valve 40 or a flow restrictor 55. The amount of fluid 23 to be drawn from the first vial 16 can be set in the chamber 56 by the manufacturer. When the plunger 60 in the chamber 56 reaches a set position within the pressure chamber 56, the plunger 60 interacts with the dispense trigger, releasing the dispense spring to force the liquid 14 from the pressure chamber 56 back into the second vial 15. Once all of the fluid 14 from the chamber 56 has been returned to the second vial 15, the solution 14 is transferred to the second pressure chamber 42, filling the chamber 42 to the extent permitted by the position of the piston 46 selected by the user or manufacturer using the dose indicator, i.e., to the extent corresponding to the desired dose. When the desired volume of the second pressure chamber 42 is reached, the second pressure chamber trigger releases the second pressure chamber spring, pushing the piston 46 forward and expelling the selected dose of injection medication 14 under pressure into the injection device 7. A check valve 40 may be used anywhere in the fluid path 35 to prevent the fluid 14 from returning to the first vial 16 during transfer of the mixture 14 from the second vial 15 to the second pressure chamber 42 and the injection device 7. A flow restrictor 55 may be used anywhere in the fluid path 35 to control the amount of mixing time in the second vial 15 before transferring the mixture 14 to the second pressure chamber 42.

[0155] 15 , an alternative transfer device 6 for a dual vial system 4 enabling mixing and transfer includes a vial holder 5 with a first vial 16 and a second vial 15, a variable volume pressure chamber 56, a dual lumen connector 94, an inlet fluid path 95, an outlet fluid path 96, and a check valve 40 that directs the contents 23 of the first vial 16 through the inlet line 95 into the pressure chamber 56 while the plunger 60 is retracted within the pressure chamber 56. When the plunger 60 is advanced after being fully retracted within the pressure chamber 56, the fluid contents 23 flow from the pressure chamber 56 into the second vial 15 and mix with the contents 56 of the second vial 15, and the resulting mixture 14 flows into the injection device 7. The check valve 40 in the outlet fluid path 96 prevents the contents 56 of the second vial 15 from being drawn into the pressure chamber 56 during the retraction phase. A check valve 40 in the inlet fluid path 95 prevents the fluid contents 23 in the pressure chamber 56 from returning to the first vial 16 during advancement of the plunger 60. A check valve in the fluid path 35 between the second vial 15 and the injection device 7 prevents the mixture from flowing back from the injection device 7 into the second vial 15. A flow restrictor 55 can be used anywhere in the fluid paths 35, 95, 96 to control the rate of fluid movement. Alternatively, a dual lumen connector 94 can similarly be used in a single vial transfer system 1 to remove and advance fluid in different fluid paths.

[0156] 16 , the pressure chamber of the above-described embodiment can be configured with an outlet port 64 that is offset or off-center compared to a typical injection device to utilize gravity. When the pressure chamber 59 fills with liquid 14 during the transfer process, air 58 may be introduced into the pressure chamber 59 in addition to the liquid 14. During the process of discharging the liquid 14 from the pressure chamber 59, it may be advantageous to control the order in which the air 58 or liquid 14 is discharged from the pressure chamber 59. For example, if the outlet port 64 of the pressure chamber 59 faces downward, during the process of discharging the liquid 14 from the pressure chamber 59, all of the liquid 14 is discharged first, and the remaining air 58 is discharged last, because the air bubbles face the top of the pressure chamber 59. Conversely, if the outlet port 64 faces upward, during the process of discharging the liquid 14 from the pressure chamber 59, all of the air 58 is discharged first, and the remaining liquid 14 is discharged last. This is particularly advantageous if a hydrophobic or hydrophilic filter is used to remove unwanted air 58 from the line when transferring the liquid 14 to the injection device 7.

[0157] The transfer device can employ various devices or procedures to enhance mixing. For example, the transfer device may swirl inject the diluent into the drug-containing vial to enhance mixing, and / or may use or incorporate mixing-enhancing elements such as dynamic or static mixers, such as a mixing ball, augers or propellers, or vibrating injection tubes. These techniques may be used within the second vial or one of the syringes. Additionally, the transfer device may have an intermediate chamber between the outlet tube of the second vial access element and the pressure chamber, enabling the enhanced mixing techniques and procedures described above. The transfer device may also be configured to move the injection vial, for example, by rotating the injection vial, to induce turbulence and enhance mixing. The use of flow restrictors in the air or drug pathways can increase the transfer time and facilitate mixing.

[0158] 16 and 17, another optional feature of the transfer device 3 is a filter 65 in the injection fluid pathway 35 for filtering the injectable agent 14 to remove particles before it is introduced into the injection device 7. The filter 65 may be a membrane, depth filter, or other suitable filtration medium having a pore size or effective pore size small enough to remove undesirable particles, including, but not limited to, undissolved injectable agent 14 in the situation where the injectable agent 14 is reconstituted by the transfer device 3.

[0159] 16 and 17, withdrawal of the injectable agent from the vial 15 may require or be facilitated by the introduction of displacement air 58 into the vial 15. In another aspect of the invention, the transfer device 3 may include a displacement air pathway or vent 66 communicating with the interior of the vial or vials to allow displacement air 58 to enter the vial 15 as the injectable agent 14 is withdrawn. As previously mentioned, the vial access member 29 for piercing the vial septum 19 is provided with an inlet tube 36 and an outlet tube 37, one for the injectable agent 14 flowing from the vial 15 and one for the displacement air 58 entering the vial 15. The displacement air 58 flow path 35 within the transfer device 3 may include a sterilizing filter 65, such as a membrane or depth filter 65 having an actual or effective pore size of about 0.22 μm or less, for filtering the displacement air 58. Such pore size is small enough to prevent pathogens from entering the vial 15 with the displacing air 58, reducing the risk of contamination of the injectable drug 14.

[0160] 16 and 17, the transfer device 3 may include an air removal device 67 in communication with the injectable agent 14 fluid path 35 from the vial 15 to the injection device 7. Such an air removal device 67 may include a bubble trap or other air gap within the injectable agent 14 fluid path 35 to remove air 58 from the injectable agent 14 fluid path 35 before the injectable agent 14 is introduced into the injection device 7. The air removal device 67 may be configured as a hydrophobic filter 65 or a combination of a hydrophobic filter 68 and a hydrophilic filter 69. The hydrophobic filter 68 allows air to escape from the transfer device 3 but does not allow the liquid 14 to pass through. The hydrophilic filter 69 allows the liquid 14 to pass through but does not allow particles or air 58 to pass through. The combination and position of the filter 69 within the fluid path 35 preferably removes all air 58 during the transfer process.

[0161] 18 and 19, the transfer device 6 can have additional features in addition to those described above. One such feature is an interlock 70 between the dose selector 48 and the vial docking station 29. This may be, for example, a mechanical interference member 97 that prevents a user from loading a vial into the docking station 29 until a dose has been selected. Mechanically, the dose selector 48 is coupled to the interference member 97 of the docking station 29. The interference member 97 is normally in an anti-load position and prevents the vial holder 5 from being inserted into the vial holder station 29 unless it is moved to the load-permitting position when the dose member 48 is moved to the dose selection position. Of course, if the injection is to be administered from vials containing a single dose of the injection, or from a single vial for all injections, the transfer device need not include a dose selection feature.

[0162] 18 and 19, the transfer device 6 may include an interlock 71 between the transfer device 6 and the injection device 7 to prevent removal of the injection device before it has been filled and to indicate when the injection device 7 is ready to be removed from the transfer device 6. Mechanically, a locking pin 72 may be coupled to the injection device 7 to prevent removal of the injection device 7 before it has been fully filled by the transfer device 6. The locking pin 72 is part of the transfer device 6 and is in communication with a piston within the pressure chamber 42. When the pressure chamber 42 has expelled all of the injection agent 14, the locking pin 72 is mechanically actuated to disengage from the injection device 7, allowing the user to remove the injection device 7 from the transfer device 6.

[0163] 18, the transfer device 6 may include an interlock between the transfer device 6 and the injection device 7 to control how the injection device 7 is removed from the transfer device 6. Mechanically, a flange or other protrusion 73 on the injection device 7 may mechanically mate with an undercut in the transfer device 6. This configuration allows the injection device 7 to be rotated in one direction relative to the transfer device 6 for removal by the user.

[0164] 18 and 19, the transfer device 6 may include a locking feature that prevents the injection device 7 from being actuated while docked to the transfer device 6. For example, a mechanical interference member, such as a locking pin, arch, or other means 72, may extend from the transfer device 6 to mechanically lock the injection device 7 to the actuator or button in the up position. Alternatively, the mechanical interference member 72 may be a shield that covers the entire injection device 7 to prevent access to the injection device 7 while it is on the transfer device 6. The arch or shield 72 may be part of the transfer device 6 and in communication with the pressure chamber 42. Once the pressure chamber 42 has expelled all of the injection agent 14 into the injection device 7, the arch or shield 72 may mechanically unlock and move away from the injection device 7, allowing a user to access and remove the injection device 7 from the transfer device 6.

[0165] Another optional feature of the transfer device is a quick-release fill port or access member between the transfer device and the injection device, which allows for quick removal of the injection device from the transfer device and prevents the injection device from being reattached to the transfer device. Once the injection device is filled and ready to be removed from the transfer device, the user can remove the injection device. The transfer device's fill tube or access member 83 is spring-loaded so that when the injection device is removed from the transfer device, the fill tube 83 springs back into the transfer device. This allows for quick removal of the tube 83 from the injection device's fill port 81 and prevents inadvertent leaks at the injection device's fill port 81. This also makes the fill tube 83 inaccessible to the user, preventing the injection device from being reattached to the transfer device.

[0166] 18 , the injection device 7 and transfer device 6 are preferably configured to allow for removably attaching the injection device 7. In this embodiment, once the injection fluid 14 is transferred from the second pressure chamber 42 in the transfer device 6 to the injection device 7 and the interlock 71 of the transfer device 6 is released, the injection device 7 is separated from the injection device docking station 30 of the transfer device 6 and is ready to be applied to the subject's skin. As previously mentioned, alternative embodiments described herein include transferring the injectable fluid directly from a single pressure chamber to the injection device.

[0167] 20, injection device 7 can be of any suitable configuration. As previously mentioned, the injection device can advantageously employ one or more features of the injection devices described in U.S. patent application Ser. No. 61 / 326,492, filed April 21, 2010, U.S. patent application Ser. No. 13 / 637,756, filed September 27, 2012, and U.S. patent application Ser. No. 61 / 704,922, filed September 24, 2012, all of which are incorporated herein by reference.

[0168] 20-22, the injection device 7 includes a generally thin, disc-shaped outer housing 74 having an upper surface 75 and a lower surface 76 from which an injection needle or cannula protrudes when activated by a user. The upper surface 75 includes an actuator or button 77 for initiating an injection and a transparent portion 80 of the housing 74 that allows a subject or medical professional to view the expandable member 78 and determine the amount of injectable fluid 79 within the device 7. For example, a user can determine whether an injection has started or ended. Preferably, the expandable member 78 and / or the transparent portion 80 of the housing 74 are graduated, such as by linear markings 127, to allow a patient or medical professional to more precisely visually determine the amount of injectable fluid 79 remaining, e.g., approximately 50% complete or approximately 75% complete. Additionally, the expandable member 78 itself may include or interact with a feature on the outer housing 74 to indicate the amount of injectable fluid 79 remaining. For example, when the injection device 7 is filled with medication 79, the transparent portion 80 may display one color, such as, but not limited to, green. When the injection device 7 is empty of medication 79, the transparent portion 80 displays a different color, such as red. During administration, the transparent portion 80 displays a combination of colors.

[0169] 23-25, the underside 76 of the injection device 7 includes a fill port 81 and an administration port 82. The fill port 81 is an interface that allows a transfer device fill tube 83 to transfer a liquid 79 into the injection device 7. The administration port 82 also includes an internal pathway 84 between the injection agent 79 ejected from the expandable member 78 and a needle 85. The fill port 81 and the dispense port 79 may be in direct fluid communication via an internal pathway 86, or may be combined into a single port.

[0170] 23-25, the injection device may preferably include a fill port 81 including a check valve 87 to prevent pressurized injection agent 79 from leaking from the injection device 7 when the injection device 7 is removed from the transfer device 6 and the fill port 81 is removed from the fill tube 83.

[0171] 23-25, the injection device 7 may also have a fill port 81 configured to accept the insertion of a syringe. The syringe may be configured using a luer fitting or a needle. This configuration of the fill port 81 allows for manual filling of the injection device by the user. The transfer device 6 can still be used, but is not required in this configuration.

[0172] 23-25, the injection device 7 may also have an administration port 82 configured to connect directly to an intravenous cannula via accessory tubing or a standard needle port.

[0173] 23-25, the underside 76 of the injection device 7 carries an adhesive 88 for temporarily securing the injection device 7 to the subject's skin until the injection is completed. Upon removal of the injection device 7, the adhesive tape backing 89 is automatically removed to expose the adhesive surface 88 of the underside 76 of the injection device 7, which can be used to attach the injection device 7 to the patient's skin. Alternatively, the tape backing 89 may be provided with a tab 90 that the user manually removes before attaching the injection device 7 to the skin. Alternatively, the tab may be attached to a surface of the transfer device 4 so that the tape backing is automatically removed when the injection device 7 is removed.

[0174] 23-25, the injection device 7 may have an adhesive tape flange 91 that extends beyond the lower base 76. This flange 91 of the adhesive tape 88 acts as a strain relief between the injection device 7 and the skin surface, reducing the risk of the injection device 7 accidentally detaching from the skin. In other words, similar to a tapered strain relief on a wire entering a connector, the extended adhesive flange 91 acts to distribute the load on both sides of the connection point between the adhesive tape 88 and the lower base 76 of the injection device 7, reducing stress concentrations at the interface of the adhesive tape 88 and the skin.

[0175] 23-25, the injection device 7 can be configured with a tapered underside 98 that presses against the adhesive flange 91 to securely attach the adhesive tape 88 to the skin when the user secures the injection device 7 to the skin without additional user intervention. By taking advantage of the flexibility of the skin when pressing the injection device 7 against the skin, the tapered underside 98 of the injection device 7 effectively presses the flange 91 of the adhesive tape 88 against the skin, but does not adhere to the upper exposed surface of the flange 91 portion because that portion is free of exposed adhesive. This significantly simplifies the method of attaching the adhesive tape 88 because the user does not need to run their finger around the flange 91 to secure the injection device 7 to the skin.

[0176] 23-25, the injection device 7 may have a lower surface 76 that is flexible or compliant rather than rigid, to improve attachment by allowing the injection device 7 to conform to the skin during application.

[0177] 26-28, after the injection device 7 is applied to or adhered to the skin 99, the safety or lockout mechanism is automatically disengaged and the injection device 7 is ready to fire (inject). In other words, the injection device 7 is inactivated (locked out) until it is applied to the skin. Alternatively, the user can manually remove a safety device 100, such as a safety pin, safety sleeve, or collar, to release the injection device and make it ready to fire (inject). Preferably, the injection device 7 cannot be fired until the safety mechanism 100 is disengaged. The safety mechanism 100 can be passive or active and can be manually activated by the user or automatically activated by the injection device 7.

[0178] 26-28, the injection device 7 can use an actuator or button 77 in combination with a visual indicator 101 to define the state of the injection device 7 after removal from the transfer device. For example, if the button 77 is in the up position and the indicator 101 is one color, such as, but not limited to, green, this can indicate that the injection device 7 is ready to begin an injection. Additionally, the button 77 can have a sidewall 102 that is a different color than its top surface 103. When the button 77 is pressed, the user cannot see the sidewall 102 of the button 77. This can indicate that the injection device 7 is in use. The injection device 7 can alert the user when the medication injection is complete. This alert can be displayed in the form of a visual indicator, an audible sound, a mechanical movement, or a combination thereof. The button 77 is ideally designed to provide the user with audible, visual, and tactile feedback when the button 77 "pops" into the lockout position. The injection device 7 may indicate to the user that administration is complete and the full dose has been administered to the patient by having the button 77 in the up position and the indicator window 101 showing that the injection device is empty. For example, if the button 77 is in the up position and the indicator 101 shows a different color, such as red, this may indicate that the injection device 7 has completed an injection.

[0179] 29-31 , the injection device 7 may be provided with an actuator or button 77 that the user presses on the injection device 7 to initiate an injection. The button 77 may be configured as an on / off switch, i.e., having only two states, open and closed, like a light switch. This prevents the user from partially depressing the button 77 and thereby activating the injection device 7. This “light switch” type button 77, when activated, quickly inserts the needle 85 into the skin 99, regardless of the user's operation of the button 77. Alternatively, the button 77 may operate continuously, allowing the user to slowly insert the needle 85 into the skin 99. The button 77 is preferably bonded directly to the needle 85 using an adhesive 104, forming the button 77 and the needle 85.

[0180] Referring to Figures 29-31, upon activation of the button 77, the injection device 7 first advances to a first position or depth, as shown in Figure 30, and then preferably automatically retracts slightly to a second depth, as shown in Figure 31, allowing the needle 85 to move through the skin 99. The first depth, as shown in Figure 30, is achieved by overtravel of the button 77 during activation. The first depth may be controlled by a feature 105 on the button 77 that directly contacts the base 106 of the injection device 7. The final needle depth 85 is suitable for subcutaneous injections. Alternatively, for intradermal injections, the final needle depth 85 may be reduced. Alternatively, for intramuscular injections, the final needle depth 85 may be increased. Once the first depth is reached, the needle 85 retracts to a second depth, as shown in Figure 31. The retraction distance to the second depth ranges from 0.1 to 2 mm. This retraction feature is preferred to prevent the needle 85 from being blocked by tissue during the initial insertion step. Very high pressures may be required to overcome this tissue blockage and prevent delivery of the agent by the injection device 7. Retracting the needle 85 from the first position to the second position creates an open pocket in front of the needle tip 107, reducing pressure and initiating agent flow from the needle 85. This reduced pressure to initiate agent flow from the needle favors the injection device 7 maintaining a relatively constant pressure during injection.

[0181] 29-31, the injection device 7 may include a needle 85 with a side hole 108. As shown in FIG. 31, when the button 77 of the injection device 7 is fully depressed, the needle 85 is fully inserted into the skin 99 through the administration port 82, and the injection device 7 begins dispensing the injection. The side hole 108 and the inner lumen of the needle 85 do not communicate with the fluid channel 86 of the dispensing port 82 until the button 77 is fully depressed. Both the side hole 108 and the needle tip 107 are retained within a septum 109. Because the side hole 108 and the needle tip 107 are retained within the septum 109, the entire medication pathway remains sterile until use. When the button 77 is fully depressed and the needle 85 is in the dispensing position, the side hole 108 of the needle 85 communicates with the fluid channel 86 of the administration port 82, and injection of the liquid begins.

[0182] 29-31, the septum 109 advantageously seals the needle tip 107 and side hole 108 from the injectable material before and after administration. Sealing the needle tip 107 and side hole 108 of the needle 85 at the end of an injection has the particular advantage of preventing the injectable material from dripping from the injection device 7 after administration is complete and / or after removal from the skin surface. It also prevents contaminants from entering the hollow needle before it penetrates the skin. The septum 109 can be made of any suitable material to provide a seal after the needle 85 penetrates it. The material composition of the septum 109 preferably includes silicone. Alternatively, the septum material composition may be a blend of different materials, including, but not limited to, butyl bromide, chlorobutyl, isoprene, polyisoprene, SBR, polybutadiene, EPDM, natural rubber, and silicone. Alternatively, the fluid pathway 86, including the administration port 82, can be a hard plastic that is silicone injection overmolded to create the aforementioned septum.

[0183] 29-31, the septum 109 of the injection port 82 may protrude slightly from the underside of the injection device 7 into the skin surface 99 to apply pressure to the skin surface 99 at the injection site. This pressure applied by the administration port 82 to the skin surface 99 after the needle is retracted may prevent leakage of the injectate from the injection site, commonly referred to as blowback.

[0184] 29-31, the injection device 7 may include a pair of spring tabs 110 that interface with the button 77 to perform a locking function. The spring tabs 110 are biased to lock into undercuts 111 in the button 77 to maintain the button 77 in an initial up or pre-fire position, as shown in FIG. 29. The shape of the undercuts 111 and spring tabs 110 help generate the light switch actuation force described above. This light switch actuation is achieved by movement of the button 77 relative to the spring tabs 110 and the shape of the mating surfaces of the undercuts 111.

[0185] 29-31, the injection device 7 may include a spring tab 112 that interacts with a button 77 in the injection device 7 to perform a locking function, such that when the button 77 is actuated to a first depth and slightly pulled back to a second depth or dispensing position, an undercut feature 113 on the button 77 allows the spring tab 112 to hold the button 77 in the dispensing position until the injection device 7 completes administration.

[0186] 32-33, the injection device 7 may include an end-of-delivery or empty indicator 114 for detecting when all of the fluid 79 has been expelled from the expandable member 78 and the injection device 7 has completed administration. The empty indicator 114 may comprise a slot or other opening 115 that slides over the expandable member 78 at the exit port when the expandable member 78 is in a contracted state after all of the fluid has been expelled. The empty indicator has two states. As shown in FIG. 32, the empty indicator is in a first position, or outwardly biased state, when that section of the expandable member 78 is filled with fluid 79 and is not contained within the slot or opening 115. This first position indicates that the expandable member 78 is not empty when the diameter of the expandable member 78 is greater than a minimum value due to residual fluid 79 contained therein. As shown in FIG. 33, the empty indicator 114 may be in a second position, or inwardly biased state, when the expandable member 78 is partially or completely received within the slot or opening 115. This second position means that the expandable member 78 is empty when at its smallest diameter.

[0187] 32-33, the injection device 7 may include an automatic needle retraction mechanism upon completion of administration. This mechanism includes a direct coupling between the aforementioned spring tab 112, button undercut feature 113, and empty indicator 114. As shown in FIG. 33, when the expandable member 78 is filled with injection 79 and the button 77 is depressed from a first pre-fire position to a second dispensing position, the undercut feature 113 of the button 77 allows the spring tab 112 to hold the button 77 in the dispensing position until the injection device 7 completes dispensing. This spring tab 112 may also be directly coupled to the empty indicator 114, which is naturally in a first or outwardly biased position. The act of depressing the button 77 to the second or dispensing position causes the support feature 116 of the button 77 to bias or pretension the spring tab 112, forcing the empty indicator 114 to the second or inwardly biased position. However, because the expandable member 78 is initially filled with injection material 79 and has a large diameter, the empty indicator 114 cannot move to the second position, or inwardly biased state, as shown in FIG. 32. After the button 77 is pressed, fluid 79 begins to be expelled through the needle and out of the expandable member 78, as previously described. Once the expandable member 78 has expelled all of the fluid 79 and is at its smallest diameter, the empty indicator 114 (under pretension from the spring tab 112) moves to the second position, or inwardly biased state, as shown in FIG. 33. The spring tab 112, which is directly connected to the empty indicator 114, also moves with the empty indicator 114. This movement releases the spring tab 112 from the undercut feature 113 of the button 77, allowing the button 77 (and needle) to move to its final, or post-fire, position after dispensing is complete, as shown in FIG. 34.

[0188] 34, the lockout spring tab 117 interacts with the button 77 of the injection device 7 to perform a locking function, releasing the button 77 once the injection is complete and allowing the button 77 to be pushed up to its final raised or post-fire position by a return spring 118. The height of the button 77 relative to the top of the injection device 7 in the final raised or post-fire position (shown in FIG. 34) may be greater than in the pre-fire position (shown in FIG. 29). The end of the lockout spring tab 117 travels within the outer housing 74 to an outer diameter surface 119 of the button 77, locking the button 77 in the up or post-fire position and preventing it from being actuated again.

[0189] 34, the injection device 7 may include a return spring 118 that interacts with the button 77 to bias the button 77 toward a first, up, or pre-fire position. When the button is depressed to a second depth or dispensing position, the return spring 118 compresses, creating a greater deflection or preload. At the end of the dispensing period, the button 77 unlocks from the second depth or dispensing position (shown in FIG. 31) and moves to a final, or post-fire position after dispensing is completed, as previously described. It is the biasing force of the return spring 118 that pushes the button 77 up to the final, or post-fire position.

[0190] 34-35, upon removal of the injection device 7 from the skin 99, the injection device 7 is preferably locked out to prevent non-destructive access to the needle and reuse of the injection device 7. The injection device 7 may indicate to the user that the full dose has been administered. This indication may be in the form of a visual indicator, an audible sound, a mechanical movement, or a combination thereof.

[0191] 35, when the injection device 7 is removed from the skin 35, the bandage 120 may become detached from the injection device 7 and remain on the skin surface 35. This may be affected by using an adhesive on the bandage that attaches the bandage to the skin stronger than the adhesive that attaches the bandage to the injection device 7. Thus, when the housing is lifted from the skin, the bandage 120 remains over the injection site as described in U.S. Pat. No. 7,637,891 and U.S. patent application Ser. No. 12 / 630,996 (filed Dec. 4, 2009, which are incorporated herein by reference).

[0192] 36-39 , the injection device 7 preferably includes a manifold 121 that is incorporated into both the expandable member 78 and the fill port 81 and administration port 82, providing direct fluid communication between the expandable member 78 and the fill port 81 and administration port 82 of the injection device 7. The manifold 121 has an increased diameter at the end that assembles to the expandable member 78, facilitating the filling and draining of all of the fluid 79 from the expandable member 78, as described above. The manifold 121 preferably includes an internal passageway 122 to allow fluid flow into and out of the expandable member 78. The manifold 121 may be configured with a filter 123 in the injectable fluid path 122 to filter the injectable fluid 79 to remove particles before and after the injectable fluid 79 is introduced into the expandable member 78. The filter 123 can be a membrane, depth filter, or other suitable filtration medium having a pore size or effective pore size small enough to remove undesired particles, including, but not limited to, undissolved injectable agent 79 when the injectable agent 79 is reconstituted by the transfer device. The manifold 121 can also be provided with a filter 123 for removing air. Such an air removal filter 123 can include an air bubble trap or other air gap configuration within the injectable fluid path 122 to remove air from the injectable fluid path 122 before it is introduced into the expandable member 78. The air removal filter 123 can be a hydrophobic filter or a combination of hydrophobic and hydrophilic filters. A hydrophobic filter allows air to escape from the transfer device but does not allow liquid to pass through. A hydrophilic filter allows liquid to pass through but does not allow particulates or air to pass through. The air removal filter 123 may also include a check valve to remove trapped air. Alternatively, the air remover and filter 123 can be located at any point in the fluid pathway from the fill port 81 to the needle 85. For example, the most downstream point in the fluid pathway is the distal end 128 of the expandable member 78. The inner mandrel 124 can be connected to the distal end 128 of the expandable member 78.An air eliminator or filter 123 may be incorporated at this downstream point to allow for the evacuation of trapped air during filling of the injection device 7. Additionally, the mandrel 124 may include slots along its length that communicate with the downstream filter 123 to remove air during the filling process.

[0193] 36-39, the injection device 7 may include an elastic expandable member 78, such as an elastic balloon or bladder. The material composition of the expandable member 78 preferably includes silicone. Alternatively, the material composition of the expandable member 78 may be a mixture of different materials, including, but not limited to, butyl bromide, chlorobutyl, isoprene, polyisoprene, SBR, polybutadiene, EPDM, natural rubber, and silicone. Additionally, the expandable member 78 may be coated to improve surface properties. Examples of coatings include parylene, silicone, Teflon, and fluorine gas treatment. Alternatively, the expandable member 78 may be made of a thermoplastic elastomer.

[0194] 36-39, the injection device 7 may include an elastic expandable member 78 through which the injectable agent 79 is delivered under pressure. This causes the expandable member 78 to expand, and the elasticity of the expandable member 78 creates pressure, tending to expel the injectable agent 79. The pressure chamber of the delivery device (or other pump or pressurizing means used in the delivery device) delivers the injectable agent 79 under pressure to the injection device 7. When the injectable agent 79 is introduced into the expandable member 78 under pressure, the expandable member 78 expands, stretching in both diameter and length. An example is the inflation of an elongated balloon. The volume range of the injection device 7 is 0.5-30 mL. When the elastic expandable member 78 expands, an expulsion pressure ranging from 1-200 psi is applied to the injectable agent 79 contained within the expandable member 78, so that the injection device 7 is automatically ready to administer the injectable agent 79 when the user presses the button to trigger the injection device 7, as described above. Thus, the aforementioned transfer device not only transfers a measured amount of injectable agent 79 to the injection device 7 (mixing, diluting, filtering as necessary), but also simultaneously charges or provides a driving pressure to the injection device 7 (by expanding the elastic expandable member 78) so that, when actuated by the user, the injection device 7 is ready to automatically dispense the injectable agent 79 under the pressure exerted by the elastic expandable member 78.

[0195] This aspect of the transfer device (simultaneous transfer and loading) is particularly beneficial. While the above applications show the injection device 7 in a pre-filled or pre-loaded state to inject the medication 79 when the injection device 7 is activated, the present disclosure contemplates the injection device 7 remaining empty, with the expandable member 78 in a more relaxed, unfilled, or unloaded state, until administration of the injectable medication 79 is required. The injectable medication 79 is then mixed or processed as needed, introduced into the injection device 7, and the expandable member 78 expands to a filled or loaded state. In the present disclosure, the medication is stored in its original sealed container (vial) until use. Because the injectable medication 79 is typically injected within seconds to hours of being transferred from the vial to the injection device 7, shelf life and material compatibility of the medication with materials in the fluid pathway within the injection device 7 are not critical. This significantly reduces the challenges and costs involved in designing the injection device 7 and selecting materials to extend the shelf life of the pre-filled injection device 7.

[0196] 36-39, the present invention can utilize the features of the injection device 7 described in the patent applications incorporated herein by reference. However, the expandable member 78 used in the injection device 7 herein may also preferably take the form of an elongated balloon or bladder arranged, for example, in a planar or three-dimensional spiral, as shown. As previously described, the injection device 7 includes a circular outer housing 74 having a helical slot or recess 125 formed therein. The elongated balloon or bladder 78 resides within the slot 125, with one end communicating directly or indirectly with the injection needle 85 via a fluid pathway 122 and the other end communicating directly or indirectly with the dosage indicator 101. The elongated helical configuration allows the balloon or bladder 78 to have sufficient volume to accommodate the desired amount of injection agent 79 while also contributing to the low-profile configuration of the injection device 7. In other words, the use of a relatively long expandable member 78 with a large length-to-diameter ratio allows very high pressures and volumes to be achieved with minimal force. Additionally, by varying the fill length, the volume of the expandable member 78 can be varied without significantly altering the pressure / volume curve of the expandable member 78 .

[0197] Referring to FIGS. 36-39, one alternative embodiment described in U.S. Patent Application No. 61 / 704,922, filed September 24, 2012, that may be employed in the present invention is the use of an insert, plug, or mandrel 124 within the expandable member 78, which pre-stresses the expandable member 78 to a slightly expanded position when unfilled, and then, as the expandable member 78 expels the injectable agent 79, contracts or collapses the expandable member 78 to a still stretched or stressed state, as shown in FIGS. 38 and 39, thereby maintaining pressure on the fluid within. This further ensures that all or substantially all of the injectable agent 79 is completely expelled from the injection device 7. If desired, the mandrel or shaft 124 can be a fluid-filled expandable member, allowing the size of the mandrel 124 to be variable. Alternatively, the expandable member 78 can have a sufficiently small internal volume (small diameter) when unstressed that substantially all of the injectable agent 79 is expelled without the need for an internal mandrel or shaft 124. Additionally, the expandable member 78 can be flattened / stretched by wrapping it around a surface within the injection device, such as a cylindrical wall 134. The prestress created in the expandable member 78 acts to expel any residual fluid volume remaining therein.

[0198] As mentioned above, there are several different ways to cause the expandable member 78 to expand and / or contract in an arcuate manner. Returning to FIG. 34 , one method is to design the expandable member 78 with a thicker wall cross-section 126 in one region around its periphery, causing the expandable member 78 to expand in a circular fashion. Alternatively, a separate element 126 can be attached along the length of the expandable member 78, effectively reinforcing the expandable member 78 in that portion of its circumference where it expands in an arcuate fashion. Returning to FIG. 36 , another method is to use internal features, such as slots or recesses 125 in the housing 74 of the injection device 7, to guide the expandable member 78 along a circular or spiral path. These features 125 can interact with the expandable member 78 in a variety of ways, but the simplest method is for the contours of the expandable member to be constrained by the slots 125 in the housing 74 of the injection device 7. Friction between the expandable member 78 and the inner surface 125 of the housing 74 can be reduced by lubricating the outer surface of the expandable member 78 or by inserting the expandable member 78 within a low spring constant spring that limits both friction and outer diameter without constraining the length of the expandable member 78.

[0199] 36-39, the elongate expandable member 78 may be preferably configured to expand along an arc at a given tube diameter without the aid of walls or guides within the injection device. Referring back to FIG. 34, looking at the cross section of the elongate expandable member 78, thicker wall regions 126 can be added to a small portion of the circumference of the expandable member 78 to cause the elongate expandable member 78 to expand in an arc as described above. As the arc-shaped expandable member 78 expands in length due to increased internal pressure and volume, the thicker sections 126 will deflect less than the thinner sections.

[0200] 36, the arcuate expandable member 78 expands longitudinally in an arcuate shape, with its thicker wall thickness regions 126, or areas of less deflection, facing inward in a circle. Increasing the wall thickness 126 of the expandable member 78 within a small circumferential region 126 effectively continues to decrease the radius of the arc of the expandable member 78. Increasing the wall thickness 126 can be accomplished by molding or extruding it into the arcuate expandable member 78, or by adhering a strip of material to one side 126 of the expandable member so that that portion of the wall 126 stretches at a slower rate, thereby causing the expandable member 78 to expand in an arcuate shape as described above.

[0201] Referring to FIG. 37 , the distal end of the expandable member 78 can be fitted with an indicator 101 or other element that is constrained to follow a guide path within the inner surface 125 of the housing 74. Alternatively, the expandable member 78 can be pre-stretched and flattened around a circular diameter inside the injection device 7, such as the wall 134, to prevent the length of the expandable member from changing. Alternatively, the expandable member can be stretched into a circular shape within the injection device 7 prior to filling using a straight or curved mandrel 124 that is longer than the unstressed expandable member. Alternatively, the mandrel 124 can be used as a visual indicator of the state of the injection device 7 and the progress of the injection. The mandrel 124 can be colored to be easily visible through the housing.

[0202] Referring to FIGS. 36-39 , an injection agent 79 is injected into the expandable member 78 by a transfer device, causing the expandable member 78 to expand to a specific outer diameter controlled by the configuration of the inner surface 125 of the housing 74. In this manner, the entire length of the expandable member 78 can be filled with a known volume of agent, and the outer diameter at each longitudinal position along the expandable member 78 is known. To encourage complete emptying of the expandable member 78 and allow for easy and accurate measurement of the fluid 79 within the expandable member, it is desirable to fill and empty the expandable member 78 in a controlled manner from one end to the other along its length. To facilitate visual determination of how much fluid 79 is remaining within the expandable member 78, graduations indicating the volume remaining in the expandable member 78 can be printed on the expandable member 78, similar to a syringe. As previously mentioned, referring to FIGS. 21-22 , the expandable member 78 and housing 74 are transparent, allowing the user to view the agent 74 and the volume remaining within the injection device 7. Alternatively, graduations 127 may be printed on the housing 74 to indicate the volume remaining in the expandable member 78 .

[0203] 36-39 , in accordance with one embodiment of the present invention described above, the injectable agent 79 is preferably gradually discharged from the distal end 128 of the elongate expandable member 78 toward the proximal end 129. The proximal end 129 of the expandable member is closest to the administration needle 82 or cannula. This allows the user to visually confirm or estimate the status of the injection, with the aid of the injection housing 74, window 80, or scale 127 on the expandable member 78, or alone. The gradual discharge can be achieved in a variety of ways. For example, the injectable agent 79 is discharged from the expandable member 78 at the manifold 121 of the proximal exit port 130, preferably located at the proximal end 129 of the elongate expandable member (e.g., a balloon or bladder). The wall thickness of the expandable member 78 may vary uniformly or in gradual increments along its length from the distal end 128 to the proximal end 129. Due to the constraint of the walls of the helical channel 125 in which the expandable member 78 resides, the expandable member 78 will expand with the injectable agent 79 to a substantially uniform diameter along its length. However, the thicker walls of the expandable member 78 at the distal end 128 will exert a greater contractile force on the injectable agent 79 than the thinner walls at the proximal end 129, causing the expandable member 78 to collapse or contract in diameter first during ejection of the injectable agent 79. The expandable member 78 will then gradually contract from the distal end 128 to the proximal end 129 as the walls become thinner along its length in that direction. Because the thickness of the expandable member 78 preferably increases substantially uniformly from the proximal end 129 to the distal or closed end 128, the contractile force as the walls of the expandable member 78 are expanded will increase substantially uniformly along the length of the elongated expandable member 78 from the proximal port end 129 to the distal or closed end 128. Thus, as the injection agent 79 is injected into the subject, the expandable member 78 gradually reduces in diameter and length. This reduction in diameter and length is preferably visible to the user, as described above. The distal end 128 of the elongate expandable member may allow for connection of a movable indicator component 101 within the injection device 7 that tracks the contraction in length of the elongate expandable member 78. This indicator 101 is preferably visible to the user through the outer housing 74 to indicate the status of the injection device 7 and the progress of the injection.Alternatively, the expandable member 78 can be constructed with a constant wall thickness and prestressed during manufacture to fill from the proximal end 129 to the distal end 128 and biased to progressively contract or empty as described above from the distal end 128 to the proximal end 129.

[0204] 36-39 , the elongated expandable member 78 of the injection device 7 can be configured to have a section 130 of the expandable member 7 adjacent the proximal exit port end 130 that fills first and contracts last during the filling and ejection of the injectable agent 79 from the injection device 7. In other words, when filling the injection device 7 with a transfer device, it is advantageous to first load the injectable agent into the proximal-most exit port 130 of the expandable member 79. Furthermore, when dispensing the injectable agent 79 from the injection device 7, it is advantageous to have the last volume of the remaining injectable agent 79 received within the proximal-most exit port 130 of the expandable member 79. This configuration has several advantages. The proximal end section 130 of the expandable member 78 can have a thin wall that allows it to remain expanded at a lower pressure than the remainder of the expandable member 78. This ensures that the section 130 of the expandable member 78 remains expanded until all of the injectable agent 79 has been ejected from the remainder of the expandable member 78. As previously mentioned, this section 130 can be directly coupled to an empty indicator to indicate full or empty. Additionally, as previously mentioned, this section 130 can be mechanically coupled to an empty indicator to automatically retract the button 77 and needle 82 when the syringe 79 is fully expelled.

[0205] 36-39 , instead of or in addition to varying the wall thickness 126 of the expandable member 78, the cross-sectional size of the elongated inner mandrel or shaft 124 within the expandable member 78 may gradually decrease (linearly or in steps) along the length of the expandable member 78 from the proximal end (exit port end) 129 to the distal end (closed end) 128 of the expandable member 78. Additionally, the manifold 121 that allows the expandable member 78 to be attached to the injection device 7 may also be configured with a larger diameter section 130 at the proximal end 129 of the expandable member 78. The larger diameter section 130 of the mandrel 124 or manifold 121 at the proximal end exit port 129 of the expandable member 78 ensures that the expandable member 78 is filled with the injectable agent 79 initially in this region 129. In other words, the expandable member 78 is held at approximately the fill diameter at the proximal end exit port 129 by the larger diameter section 130 of the mandrel 120 or manifold 121. When the fluid 79 first begins to fill the expandable member 78, the fluid 79 first reaches the fill diameter at the larger diameter section 130 and then gradually fills along the length of the expandable member 78 from the proximal end 129 to the distal end 128, as previously described.

[0206] 36-39 , as previously described, during dispensing of injectable material 79 from expandable member 78, the diameter of the distal end of expandable member 78 continuously and progressively contracts (similar to deflating an elongated balloon) from distal end 128 toward proximal end 129 until all fluid is expelled from expandable member 78. A larger diameter section 130 of mandrel 124 or manifold 121 at proximal end outlet port 129 of expandable member 78 provides the same advantage during dispensing of injectable material 79 (as previously described with respect to filling). This larger diameter section 130 ensures that any final fluid 79 remaining within expandable member 78 is contained within this region 130 and expelled therefrom. As previously described, this section 130 can be directly coupled to an empty indicator to provide a full / empty indication as well as automatically withdrawing button 77 and needle 82 when injectable material 79 is fully expelled.

[0207] Operation and Method 40-42, sterile injection devices 7 are mounted in transfer device 3 in covered tray 132, and separately packaged vial holders 2 containing filled vials are provided in carton 131. The user places carton 131 on a clean, flat surface. The user opens lid 133 of carton 131, exposing transfer device 3 and vial holder assembly 2. The user removes cover 132 from transfer device tray 3, exposing transfer device 3 and injection device 7. The user is instructed to leave transfer device 3 in carton 131 and, if directed, remove only injection device 7.

[0208] 43-44, during use, a user removes the vial holder assembly 2 from the carton 131. Next, the user removes the vial cap from the vial using the attached cap remover. The user inserts the vial holder 2 into the transfer device 3. The user activates the system 1 by pushing the vial holder 2 with the attached vial 16 into the transfer device 3. In the illustrated embodiment, this accomplishes three things: first, it locks the vial holder 2 with the attached vial 16 into a lower position within the transfer device 3; second, it automatically initiates fluid communication between the contents 23 of the vial 16 and the transfer device 3 by introducing an access member through the vial's septum; and third, it initiates the mixing and transfer sequence of the transfer device 3 (if necessary). This sequence of events occurs automatically and requires no additional input from the user to proceed.

[0209] Referring to Figures 45-47, a dual-vial system 4 requiring mixing may allow the user to adjust the dose delivered. The dose selector 48 is moved from the initial position shown in Figure 46 to the final delivery volume position shown in Figure 47. At this point, the vial holder 5 can be freely depressed by the user to begin mixing and transfer. First, the diluent is transferred from the diluent vial and injected into the powdered lyophilized injection vial. The fluid is introduced into the powder vial, and any powder is removed as the fluid is transferred from the vial. Mixing of the diluent and powder may be completed entirely within the powder vial or within the transfer device. Static or dynamic mixing elements may be incorporated into the transfer device or introduced into the powder vial by the transfer device to ensure proper mixing of the powdered drug or other injectable and diluent. Mixing may take several minutes to complete. Mixing is performed in as gentle a manner as possible to minimize air bubbles / foaming and shear stress within the mixture. Mixing is performed to ensure the powder is thoroughly mixed and free of particles. In-line filters, valves, or other means may be used to remove particles and air. The transfer device may have an indicator to show when mixing is in progress.

[0210] 45-47, in dual vial system 5, the reconstitution solution is mixed in a powder vial or transfer device 6, and a set volume of solution, specified by the manufacturer or set by the user, is automatically transferred to a pressure dosing chamber. This set volume is then automatically transferred to an injection device 7. The volume of tubing, conduits, valves, and other fluid pathways between the vial and transfer device 6 is minimized to allow for the transfer of a maximum percentage of the medication to the injection device 7.

[0211] 48-50, once the required dose volume has been delivered to the injection device 7, the injection device 7 may have a transparent area or other indicator 80, 101 that allows the user to visually inspect the mixed solution to ensure complete mixing. Ideally, the user should be able to see the total volume of medication in the injection device 7. An indicator 101, such as a relative fill gauge, may also be provided to indicate that the correct dose has been delivered to the injection device 7. Once mixing and transfer to the injection device 7 is complete, the injection device 7 is unlocked and can be removed from the transfer device 3, 6, or injection device docking station. The injection device 7 may indicate to the user that it is ready by having the button 77 in the up or ready position and the indicator window 80, 101 showing that the injection device is full.

[0212] 50, the user can remove the injection device 7 from the delivery device 3 by twisting or pulling the injection device 7 from the delivery device 3. Upon removing the injection device 7, the adhesive tape backing is automatically removed, exposing the adhesive surface at the bottom of the injection device, which can be used to adhere the device to the patient's skin. Alternatively, the tape backing has a tab that the user can manually pull to remove it before applying the device to the skin.

[0213] 51, the user attaches the injection device 7 to the skin 99. The injection device 7 may be provided with an adhesive at the bottom to adhere to the surface of the skin 99 for hands-free operation. The adhesive may extend beyond the contours of the injection device to allow the user to securely tape it to the skin. Alternatively, the user may hold the injection device 7 against the skin 99 during the injection.

[0214] Referring to Figures 51-53, the user removes the safety device 100 and presses the button 77 on the injection device 7 to begin the injection. When the button 77 on the injection device 7 is fully depressed, the button locks into place, the needle is fully inserted into the patient's body, and the injection device 7 begins administering the injected medication. The injection device 7 can alert the user that medication injection has begun. This alert can be in the form of a visual indicator, an audible sound, a mechanical movement, or a combination thereof. The injection time can range from a few seconds to several hours. The injection device 7 can indicate to the user that an injection is in progress by locking the button 77 in the down position and displaying the indicator window 101 to indicate that the injection device 7 is not full. The injection device 7 preferably includes a transparent portion 80 that allows the user to easily determine the amount of medication remaining in the injection device 7.

[0215] Referring to Figure 54, the user is alerted when the medication injection is complete. This alert can be in the form of a visual indicator, an audible sound, a mechanical movement, or a combination thereof. The injection device 7 can notify the user that the injection is complete by moving the button 77 to the locked position, accompanied by a tactile and audible sound, and displaying the indicator window 101 indicating that the injection device is empty. At the end of administration, the needle automatically retracts to the locked position within the injection device 7.

[0216] 54, when the injection device 7 is removed from the skin 99, the bandage 120 may detach from the injection device 7 and remain on the skin surface 99. Upon removal from the skin 99, the injection device 7 is preferably locked out to prevent non-destructive access to the needle and reuse of the injection device 7. The injection device 7 may indicate to the user that the full dose has been administered. This indication may be in the form of a visual indicator, an audible sound, a mechanical movement, or a combination thereof.

[0217] In accordance with a further aspect of the present invention, when performing an injection using a syringe and needle intended for injection under the skin, it is desirable to know whether the needle is properly placed within the skin or improperly placed within a blood vessel. Users administering intradermal (ID), subcutaneous (SC), or intramuscular (IM) injections typically aspirate the syringe by pulling back on the plunger to release pressure within the syringe and checking to see if visible blood enters the syringe through the needle. Visible blood indicates that the tip of the needle is within a blood vessel. Many injectable medications intended for subcutaneous injection are labeled not to be injected into a blood vessel. Using a syringe and needle to aspirate blood is a common technique and can be performed by anyone with sufficient training. However, with the increasing use of medications in automatic injection devices, the ability to manually aspirate these types of systems is nonexistent. Once the injection device is placed against the skin and the needle is fired, there is no way for the user to know whether the needle is properly placed within the skin or improperly placed within a blood vessel. Therefore, a need exists for an apparatus and method for aspirating blood within an automatic injection device.

[0218] 55-56, the injection device 7 may have a needle 85 with a side hole 108 that operatively engages a button 77 that is slidable within a septum 109 that advances into the skin 99. The button 77 may include a viewing window 160 on the button top 103 that is in fluid communication with the proximal end 161 of the needle 85. The button top 103 may include a cavity 162 that can collect blood 159 and be visible to the user through the button window 160. The cavity 162 may include a central hole 163 that allows fluid communication with the proximal end 161 of the needle 85 via a needle lumen 165. An outer wall 164 of the cavity 162 is formed by the button top 103. Additionally, a portion of the outer wall 164 may include a hydrophobic filter 166. In this configuration, the proximal end 161 of the needle 85 is at atmospheric pressure. As the fluid 14 or blood 159 moves up the internal lumen 165 of the needle 85, it exits the proximal end 161 of the needle 85 and fills the cavity 162. The air 167 within the cavity 162 is easily expelled through the hydrophobic filter 166, until all of the air 167 is expelled from the cavity 162 and the cavity 162 is filled with the fluid 14 or blood 159. At this point, the flow of the fluid 14 or blood 159 stops because the fluid 14 or blood 159 cannot pass through the hydrophobic filter 166, and can be easily viewed by the user through the window 160 in the button top 103.

[0219] 56, when the button 77 is actuated (or depressed), the needle 85 and button 77 move to a first position or depth as shown in FIG. 56. At this first position or depth, the side hole 108 is covered by the septum 109, and therefore the internal lumen 165 of the needle 85 is not in communication with the fluid channel 86 of the administration port 82. When the needle tip 107 is within the blood vessel 158 at the first position or depth, pressure within the blood vessel 158 forces blood 159 up through the internal lumen 165 and into the proximal end 161 of the needle 85, filling the cavity 162 with blood 159. This blood 159 is visible through the button window 160 in the top 103 of the button 77, providing a method for determining whether the needle 85 of the injection device 7 is within the blood vessel 158.

[0220] Referring to Figure 57, needle insertion into tissue can generally be divided into four stages. These include non-contact, boundary displacement, tip insertion, and shaft insertion. During boundary displacement, the tissue boundary in the contact area deflects under the load applied by the needle tip, but the needle tip does not penetrate the tissue. As the needle tip begins to penetrate the skin, the skin boundary moves along the needle tip to the point of maximum boundary displacement in the contact area. After the needle tip penetrates the skin, the shaft inserts into the tissue. Even after tip and shaft insertion, the skin surface boundary in the contact area does not return to its original non-contact state but remains displaced by a distance x. The boundary displacement x is a function of several parameters, including the needle diameter, needle tip shape, needle shaft friction, needle insertion speed, and physical properties of the skin. The skin boundary displacement x in the contact area affects the amount of skin penetration by the needle and is an important characteristic of needle-based injection devices because it reduces the actual needle penetration depth by the amount of boundary displacement x. If a boundary displacement x can be intentionally induced by stretching or preloading the skin at the contact site before needle tip insertion, no additional boundary displacement occurs due to the needle tip or shaft during insertion, allowing for predictable needle tip depth definition. The advantage of this intentional displacement is that the needle penetration depth into the tissue is unaffected by changes in boundary displacement x. Without intentionally inducing a boundary displacement at the skin surface before needle tip insertion, the naturally occurring boundary displacement x shown in Figure 57 would cause a portion of the needle length (depending on the parameters mentioned above) to extend beyond the skin, making the actual needle penetration depth into the skin unknown. On the other hand, if a maximum boundary displacement is induced at the contact site, the actual needle penetration depth is unaffected by changes in the aforementioned parameters, such as needle diameter, needle tip shape, needle shaft friction, needle insertion speed, and skin physical properties.

[0221] 58 , the injection device 7 may have a skin boundary displacement extension or structure, such as a lower surface 76 including an extension 138, at or around the administration port 82, or as part of the administration port 82. When the injection device 7 is attached to the skin 99, the extension 138 protrudes from the surface of the skin 99, resulting in a displacement of the skin 99 at this contact area 139. Actuating the button 77 from the pre-fire state to the first position causes the needle 85 to exit the injection device 7 and advance through the administration port 82 and / or extension 138 into the skin 99, initiating administration of the medication. For the reasons discussed above, as the needle 85 advances from the injection device 7, the tip of the needle 107 does not cause additional boundary displacement 141 (already intentionally induced by the extension 138) in the skin 99 at the contact area 139. Thus, the actual needle penetration depth 140 into the skin 99 is better characterized and controlled.

[0222] Referring to FIG. 60, the vial access member 21 of the transfer device 3 may be configured with multiple lumens, such as a multi-lumen tube 34, that communicate with the internal fluid pathway 35 of the transfer device 3. The vial access member 21 preferably includes one inlet tube 36 that allows air or fluid to enter the vial 12 and one outlet tube 37 that allows air or fluid to exit the vial 12. The lumen openings 38 of the vial access member 21 can be positioned such that the inlet tube opening 36 is above the outlet tube opening 37 when the vial is mounted in an inverted position, as shown in FIG. 59, for example. This orientation allows air or liquid to be introduced through the upper inlet tube 36 and the vial contents 14 to exit through the lower outlet tube 37. Additionally, the outlet opening 37 can be positioned near the bottom of the lower end of the vial 12, adjacent to the septum 19, so that the entire contents 14 of the vial 12 can enter the outlet port 37 and be removed from the vial 12. Once the vial 12 is placed in the vial holder docking area 29 of the transfer device 3, the vial access member 21 gains access to the contents 14 of the vial 12. As the transfer device 3 begins to withdraw the contents 14 from the vial 12 through the outlet tube 37, a pressure drop 154 ​​is created within the vial 12. This pressure drop 154 ​​draws displacement air 58 into the vial 12 through the inlet opening 37 of the vial access member 21, replacing the fluid 14 being withdrawn. In some cases, depending on the amount of injectable solution 14 in the vial 12, the liquid level 153 within the vial 12 may be above the vial access member 21, specifically above the inlet tube opening 37. As the air 58 is drawn into the vial 12 through the inlet opening 37, bubbles 155 are generated within the fluid 14. Due to buoyancy, the air bubbles 155 move to the top of the vial 12 along with the existing air 58. For some injectable solutions 14, introducing air bubbles 155 into the solution is undesirable. This results in more bubbling, frothing or foaming within the liquid 14 .

[0223] Referring to FIG. 61 , the extension member 156 can be slidable within the inlet opening 36 of the vial access member 21. The outer diameter of the extension member 156 can be configured to fit snugly against the inner diameter of the inlet opening 36. The extension member 156 can have an inner diameter that allows air 58 to pass through. When a pressure drop 154 ​​within the vial 12 draws air 58 into the vial 12 through the inlet vent 36, the air 58 initially pushes against the extension member 156 like a piston within the inlet opening 36. The extension member 156 has a sufficient length so that it will not escape through the inlet opening 36. The extension member 156 continues to slide through the inlet opening 36 until its end stops at the top 157 of the vial 12, which is well above the liquid level in the vial 153. The top of the inverted vial 12 acts as a stopper for the extension member 156. The tip of the extension member 156 may be tapered so as not to impede flow through its inner diameter when it contacts the top of the inverted vial 12. Air 58 continues to travel through the inner diameter of the extension member 156 until all of the fluid 14 within the vial 12 has been withdrawn from the vial 12 through the outlet tube 37. As previously mentioned, the outer diameter of the extension member 156 fits snugly against the inner diameter of the inlet opening 36, preventing air from leaking between these interfaces. The extension member 156 prevents air 58 from becoming trapped in the liquid 14 within the vial 12 and creating bubbles 155.

[0224] Referring to FIG. 62 , the pressure chamber 59 may be configured with an inlet port 168 used to introduce the fluid 14 and air 58 into the chamber. Additionally, the pressure chamber 59 may be provided with an outlet port 64 for evacuating the fluid 14 and / or air 58 from the chamber 59. These ports 168, 64 may be positioned off-center of the pressure chamber 59 to help control the order in which the fluid 14 and air 58 are introduced into and / or evacuated from the pressure chamber 59. As previously mentioned, the outlet port 64 of the pressure chamber 59 may be positioned downwardly from the inlet port so that, during the process of evacuating the liquid 14 from the pressure chamber 59, all of the liquid 14 is evacuated first, followed by the remaining air 58, with the air in the chamber 59 being directed toward the top of the pressure chamber 59. Additionally, as shown in FIG. 62 , the outlet port shape 169 may be configured to be non-circular so that the entire liquid contents 14 in the pressure chamber 59 enters the outlet port 64 and is removed from the pressure chamber 59 before the air 58 is removed from the pressure chamber 59. Additionally, as shown in FIG. 62, a portion 170 of the outlet port 64 may be located below a surface 171 of the pressure chamber 59. This may act as a trap to further facilitate the entire liquid contents 14 within the pressure chamber 59 entering the outlet port 64 and being removed from the pressure chamber 59 before the air 58 is removed from the pressure chamber 59.

[0225] 63, when liquid 14 is removed from vial 12 using vial access member 21, only fluid 14 is removed through outlet opening 37 until liquid level 153 drops to the top of outlet opening 137. At this point, a mixture of liquid 14 and air 58 is removed. Referring to FIG. 63, vial access member 21 further has outlet opening 37 configured in a non-circular manner to reduce the height of the opening and increase the width of the opening, thereby allowing more of the liquid contents 14 of vial 12 to enter outlet port 37 and be removed from vial 12 before air 58 is removed from vial 12.

[0226] Referring to Figures 64 and 65, a combination of hydrophobic and hydrophilic filters 68 and 69 in the fluid pathway 35 between the vial 15 and the injection device 7 preferably allows for filtration of the medication 14 and removal of air 58 during the transfer process. These filters may be separate components or may be combined into one component. Each filter may be constructed from a variety of materials, such as mixed cellulose ester (MCE), polyvinylidene difluoride (PVDF), polytetrafluoroethylene (PTFE), nylon, or polyethersulfone (PES). The pore size of each filter ranges from 0.22 to 3 µm. Each filter may have a coating to render it hydrophilic or hydrophobic.

[0227] When administering injections intended to be administered subcutaneously, a common reaction is swelling at the injection site. This reaction is particularly pronounced at a single subcutaneous site when the injection volume is large or the injection rate is fast. When these injections are administered using a syringe and needle or an administration set, swelling at the injection site does not affect the injection device. However, as medications are increasingly delivered in automatic injection devices that are attached to the body during injection, swelling at the injection site makes it difficult to secure the automatic injection device to the body. In particular, if the injection device adhesive is not properly designed, a lump or bump formed by the injection solution on the skin surface can cause the automatic injection device to become dislodged from the injection site. Therefore, there is a need for an automatic injection device with an adhesive properly designed to withstand swelling at the injection site without compromising the adhesion of the device to the patient.

[0228] Referring to Figure 66, there are two interfaces involved in adhering the injection device 7 to the skin 99. The first is the adhesive / device interface 173 and the second is the adhesive / skin interface 174.

[0229] 67, the adhesive 88 may be configured on the injection device 7 to have at least two zones. A first zone 175 includes a permanent bond between the adhesive 88 and the injection device 7 using mechanical or chemical means and is preferably located within the circumference of the injection device 7. A second zone 176 may be configured to be removable or unattached from the injection device 7 and is preferably located adjacent to and outside (e.g., radially outward from) zone 1.

[0230] Referring to Figure 68, if the adhesive 88 were fully adhered to the bottom 76 of the device 7, during a tissue swelling 177 event, the adhesive 88 at the adhesive / skin interface 174 would begin to peel away from the skin 99 because this interface 174 is weaker than the adhesive / device interface 173. This is demonstrated by the bulging surface in Figure 68. As a result, the injection device 7 could detach from the skin surface 99 and fall off the patient's body.

[0231] 67 and 69 , instead of permanently attaching the adhesive 88 to the bottom 76 of the injection device 7 as shown in FIG. 68 , the adhesive 88 can be configured on the injection device 7 to have the zones 175, 176 described above. In this configuration, upon a tissue swelling event 177, the adhesive 88 in the two zones 176 separates from the injection device 7 and firmly adheres to the surface of the skin 99 at the adhesive / skin interface 174. This allows the peeling edge 178 to transfer from the adhesive / skin interface 174 to the adhesive / device interface 173, effectively providing strain relief at the adhesive / skin interface. The adhesive / device interface 173 may be designed to be stronger and prevent the injection device 7 from separating from the skin surface 99.

[0232] When using an autoinjector to self-inject, protecting the user from accidental needlestick injuries is a beneficial requirement for the device. Typically, the needle retracts into the device before and after use, preventing the user from accessing the needle. However, during injection, the needle extends outside the device. If the autoinjector is worn on the body and accidentally becomes detached from the user during an injection, the needle may become exposed and pose a needlestick hazard to the user. Therefore, there is a need for an autoinjector with a skin detachment sensor that automatically retracts the needle if the device becomes detached from the skin during an injection.

[0233] 70-72, the skin detachment sensor 179 operatively engages a flexible latch 181 on the button 77 and is slidable within the lower housing 180 of the injection device 7. Referring to FIG. 71, when the injection device 7 is attached to the skin surface 99, the skin detachment sensor 179 is depressed to a first or up position 182 within the injection device 7. When the button 77 is actuated to the fired state or the second or dispensing position (exposing the needle 85), the flexible latch 181 is forced to a locked position 187 by the skin detachment sensor 179 below the latch board 183. The latch board 183 depresses the button 77 with a latch board surface 184, holding the button 77 in the fired or dispensing position until dispensing is complete. At the end of dispensing, the latch board 183 moves away from the latch board surface 184 on the button 77, retracting the button 77 and needle 85 to the post-fire position so that the needle 85 is received within the injection device 7. 72, if the injection device 7 is disengaged from the skin surface 99 during an injection, the skin disengagement sensor 179 extends from the injection device 7 to a second or lower position 185. This causes the flexible latch 181 to spring back to the unlocked position and disengage from the latch board 183. This causes the button 77 and needle 85 to retract to a post-fire position where the needle 85 is received within the injection device 7.

[0234] When using an injection device and needle to self-inject, a user may need to temporarily stop or pause the injection due to acute pain or inflammation at the injection site. Pausing the flow of injectable medication to the injection site by removing pressure from the injection device's plunger rod allows more time for the injected fluid bolus to diffuse into the surrounding tissue, reducing local pressure and the associated pain and irritation, thereby helping to reduce pain at the injection site. However, as more medications are being loaded into automatic injection devices, the ability to manually pause these automatic systems does not exist. Once the automatic injection device is placed against the skin and the cannula is inserted, there is no way to pause the injection due to pain or inflammation at the injection site. Therefore, a need exists for a user to be able to pause an automatic injection system.

[0235] 73-74, when button 77 is actuated, needle 85 and button 77 move to a first position or depth, as shown in FIG. 73. At this first position or depth, side hole 108 is covered by septum 109, and thus, internal lumen 165 of needle 85 is not in communication with fluid channel 86 of administration port 82. Button 77 may be intentionally held at this first position or depth to prevent injectable agent 14 from flowing from fluid channel 86 into side hole 108 of needle 85 and onto skin 99. As shown in FIG. 74, when button 77 is released, needle 85 and button 77 return to a second, or dispensing, position, exposing side hole 108 to fluid channel 86 and allowing injectable agent 14 to flow from fluid channel 86 into side hole 108 of needle 85 and onto skin 99 until the injection is completed. This operation of pressing button 77 to the first position or depth can be performed as many times as necessary throughout the injection.

[0236] 75-76, the actuation force 186 of the button 77 is the transitional load applied to the button 77 required to displace the button 77 and needle 85 from the pre-fire position to the fired or dispensing position. Until this transitional load is met, the force 186 applied to the button 77 is transferred directly to the injection device 7. Specifically, this load 186 is transferred to the adhesive / skin interface 174 and / or the adhesive / device interface 173, thereby firmly securing the injection device 7 to the skin surface 99 prior to actuation of the injection device 7.

[0237] Referring to FIG. 77 , there may be an indicator window 172 on the transfer device 3 that indicates the progress of transfer and / or mixing of the fluid 14. This indicator window 172 may be configured in the base of the transfer device 3 and may track the movement of the plunger 93 in the pressure chamber 56 within the transfer device 3. The indicator window 172 may be configured with a scale or other means for tracking the movement of the plunger 93. Alternatively, the plunger 93 may be configured with a different color to make the movement of the plunger 93 easier to track through the indicator window 172. The indicator window 172 and plunger 93 in combination may indicate the progress of the evacuation of the fluid 14 from the vial 12 and the filling of the chamber 56. The indicator window 172 and plunger 93 in combination may also provide the progress of the movement of the fluid 14 from the chamber 56 to the injection device 7.

[0238] 78-79, the arcuate expandable member 78 is arranged in an arcuate shape and / or preferably expands longitudinally in an arcuate shape. In the illustrated embodiment, the arcuate shape is induced by providing a region of less elasticity, e.g., a thicker or relatively thicker wall thickness zone 126, which results in less deflection of the expandable member in that zone and the resulting expanded arcuate shape. This thicker wall thickness zone 126 can be configured in any shape that allows the expandable member 78 to assume an arcuate shape upon expansion. A preferred configuration for the thicker wall thickness zone 126 is to minimize the circumferential thickness or attachment 150 at the wall of the expandable member 78 and maximize the radial thickness or protrusion 151 away from the expandable member 78. This not only encourages the expandable member 78 to expand in an arcuate shape, but also maximizes the amount of material along the circumference that is not affected by the thicker wall thickness zone 126 upon expansion. To force the expandable member 78 into an arc, the ends of the radial projections 152 may be configured with additional features, including but not limited to a T-shape.

[0239] 80 , the volume of the pressure chamber 56 can be set to be greater than the total fluid volume 14 in the vial 15, thereby drawing additional air 58 from the vial 15 into the chamber 56. This additional air 58 can help ensure that all of the liquid 14 is removed from the vial 15 and can also help remove or clear any residual liquid 14 in the fluid pathway 35 between the vial 15 and the chamber 56. Furthermore, during transfer of the liquid 14 from the chamber 56 to the injection device 7, the additional air can help remove or clear any residual liquid 14 in the fluid pathway 35 between the chamber 56 and the injection device 7.

[0240] Referring to FIG. 81 , the transfer device 3 includes a vial holder docking area 29 that may include an elongated vial access member or piercing member 21. The vial holder docking area 29 may include a vial access protector 136. The vial access protector 136 is locked and held in a first position on the vial access member 21 by locking fingers 137 within the vial holder docking area 29 prior to insertion of the vial 12 or vial holder, covering the vial access member 21 and preventing a user from accidentally piercing the vial access member 21. When the vial 12 or vial holder is inserted into the vial holder docking area 29, the vial 12 or vial holder moves the locking fingers 137, unlocking the vial access protector 136. Once unlocked, the vial access protector 136 becomes slidable and movable within the vial holder docking area 29 along with the vial 12 or vial holder.

[0241] Referring to FIG. 82 , a flow restrictor 55 can be used within the fluid pathway 35 to control and / or delay transfer time and / or extend mixing time. Small lumen tubing can be used at any point in the flow path 35 to restrict flow and extend mixing / transfer times up to an hour or more. One way to control and / or delay transfer time and / or increase mixing time between the second pressure chamber 42 and the injection device 7 is to use a multi-lumen fluid pathway 142 between the second pressure chamber 42 and the injection device 7. Each lumen 143, 144 of the fluid pathway 142 is attached to specific locations 145, 146 on the second pressure chamber 42, preferably spaced along the piston travel, and has an inner diameter 147, 148 sized to provide a specific flow rate through that lumen 143, 144 based on the pressure within the second pressure chamber 42. Initially, as the second pressure chamber piston 46 begins to advance within the chamber 42, the fluid mixture 14 is dispensed through all lumens 143, 144 of the fluid pathway 142 and into the injection device 7. When the piston passes the connection point 145 between the lumen 143 and the pressure chamber 42, fluid flow through that lumen 143 stops, and the fluid 14 is forced out through the remaining lumens 144. Multiple lumens and connection points can be located along the pressure chamber. The resulting lumen 144 resulting from the fluid flow 14 can be sized to have a very small inner diameter 148. Therefore, the flow rate will be very small, and it will take a long time to transfer the fluid 14 from the chamber 42 to the injection device 7. This transfer delay can increase the mixing time.

[0242] Referring to FIG. 83, a safety device such as a safety pin or safety sleeve 100 can be configured to allow it to be removed from the injection device 7 in any direction, freeing the injection device 7 and making it ready for firing (injection).

[0243] Referring to FIG. 84, the injection device 7 includes a needle 85 with a side hole 108 that allows fluid communication between the fluid channel 86 and the skin 99 when the button 77 is fully depressed within the injection device 7. This initiates administration of the injection agent 14. The inner diameter 165 of the needle 85 is important in controlling the rate of dispensing from the injection device 7. Referring to the Hagen-Poiseuille equation for fluid flowing through a pipe, the flow rate through the pipe is directly proportional to the fourth power of the pipe's radius. Therefore, small changes in the inner diameter 165 of the needle 85 result in large changes in flow through the needle 85, especially as the inner diameter 165 decreases. The needles 85 of the injection device 7 range from 21G to 34G (stub wire gauge system) in various wall thickness configurations. This range corresponds to an inner diameter 165 range of 0.021 inches to 0.003 inches, recognizing that there may be manufacturing variations or tolerances in the needle inner diameter 165 for a particular needle size. This is based on the needle size, with variations in inner diameter of up to ±0.00075 inches. To limit the range of inner diameter 165 and resulting flow rate variations within any given needle size, the needle 85 can be modified before assembly into the injection device 7. This modification involves crimping, flattening, or rolling the needle 85 from round to non-round over a portion of its length to a new, defined effective inner diameter 165. This has the advantage of allowing for specific delivery rate control from the injection device 7.

[0244] Referring to Figures 85-86, the lumen opening 38 of the vial access member 21 can be oriented to allow pressurized air or liquid to be introduced through the upper inlet tube 36 and the vial contents 14 to be discharged through the lower outlet tube 37. Additionally, the outlet opening 37 can be positioned near the bottom of the inverted vial 12, adjacent to the septum 19, so that the entire contents 14 of the vial 12 enter the outlet port 37 and are removed from the vial 12. The preferred sequence for removing the contents 14 from the vial 12 is to first remove all of the fluid 14 within the vial 12, and then remove the air 58 from the vial 12. This is achieved in this embodiment when the transfer device 3 is oriented as shown in Figures 85-86. Based on the configuration of the vial access member 21 within the vial 12, this sequence of removal of all of the fluid 23 and air 58 is achieved by the transfer device 3 at an angle of ±45 degrees from horizontal. Beyond this angle, air 58 may be introduced before or during the removal of the fluid 14 from the vial 12. An angle sensor 149 may be positioned within or around the vial access member 21 to sense the angle of the transfer device 3. It may be in direct communication with one or both of the lumen openings 38 and / or with each or both of the inlet tube 37 and outlet tube 36. In the current embodiment shown in FIG. 85, when the transfer device 3 is angled less than 45 degrees, the sensor 149 allows fluid communication between the outlet port 37 and the fluid pathway 35. As shown in FIG. 86, when the transfer device 3 is tilted to an angle greater than 45 degrees, the sensor 149 may rotate or move to a new position, blocking fluid communication between the outlet port 37 and the fluid pathway 35.

[0245] 87, an alternative transfer device 3 in a single vial system is provided that does not perform mixing and simply transfers fluid 14 from a single vial 12 to an injection device 7. This alternative transfer device 3 includes a vial 12, a variable volume pressure chamber 56, and a fluid pathway 35 that directs the contents 14 from the vial 12 to the injection device 7. The inlet tube 36 of the vial access member 21 is connected to the variable volume pressure chamber 56 via the fluid pathway 35. The outlet tube 37 of the vial access member 21 is connected to the injection device 7 via the fluid pathway pressure chamber 56.

[0246] Referring to FIG. 87, when a vial 12 is fully inserted into the transfer device 3 by a user, the vial access member 21 is introduced through the septum 19 of the vial 12, allowing access to the contents 14 of the vial 12. This initiates the release of the pressure chamber trigger 59. The plunger 60 is in a retracted position, and the pressure chamber 56 is filled with air 135. The pressure release trigger 59 releases the plunger 60 in the pressure chamber 56, which is connected to the dispense spring 63. The dispense spring 63 advances the plunger 60, forcing the air 135 out of the pressure chamber 56 through the inlet tube 36 and into the single vial 12. The air 135 entering the vial 12 forces the fluid 14 out of the vial 12 through the outlet tube 37 and into the injection device 7. This continues until all of the fluid 14 has been forced out of the vial 12 and into the injection device 7. A check valve 40 can be used to prevent the fluid 14 from returning to the vial 12 or the fluid 14 from returning to the pressure chamber 56.

[0247] An injection device including an alternative embodiment of an automatic needle retraction mechanism is shown in Figures 88A and 88B. As shown in Figures 88A and 88B, the injection device, generally designated 200, like the previous embodiment, includes a resilient bladder 202 that expands to receive and store medical fluid for injection into a patient. With the exception of the automatic needle retraction mechanism described below, the injection device features the same structure and operates in the same manner as described in the previous embodiment.

[0248] As described below, the injection device may include a post-injection lockout feature that prevents the button cap 214 from being depressed after an injection, thereby preventing deployment of the injection cannula after the injection is completed.

[0249] As shown in FIGS. 88A and 88B , a delivery termination member, generally designated 204, includes an open-end slot 206 and a latch tab 208. A button, generally designated 210, includes a button undercut 212 and is provided with a button cap 214. As shown in FIG. 88A and as previously described, the elastic bladder 202 expands when filled with injectable medication. The expansion of the bladder forces and holds the delivery termination member 204 radially inward to the position shown in FIG. 88A . When the delivery termination member 204 is in the position shown in FIG. 88A , the undercut 212 is positioned vertically above the latch tab 208. As explained in more detail below, this provides the injection device with premature lockout prevention, ensuring that the device will not lock out the button 210 if the button is only partially depressed.

[0250] As described in the previous embodiment, the button cap 214, and therefore the button 210, of the injection device 200 is pressed against the biasing force of the coil return compression spring to extend and deploy the injection cannula from the bottom of the injection device housing 218. As described in more detail below, when the button cap 214 is pressed, the button undercut 212 moves downwardly past the latch tab 208, causing the two structures to engage if the button cap 214 is released before being fully depressed to the dispensing position.

[0251] When the button cap 214 is pressed, posts formed on the button 210 engage the leaf spring 216, which urges the delivery termination member 204 radially outward against the expanded bladder.

[0252] When the button cap (and therefore undercut 212) is further depressed downward by the user to the dispense position, the button undercut 212 disengages from the latch tab 208. A mechanism, described below, holds the button 210 in the dispense position when the user releases the button cap 214 and automatically releases the button once the dispense, i.e., injection, is complete. While in the dispense position, the button 210 can be further depressed downward to a pause position, in which the flow of medication from the elastic bladder 202 to the injection cannula is interrupted, as described above. This flow resumes when the button cap is released and, as a result, lifted back to the dispense position by the return spring.

[0253] As medical fluid flows from the elastic bladder of the injection device through the cannula of the injection device and into the patient's body, the diameter of the bladder decreases. As shown in FIG. 88B, when the fluid in the bladder is empty or nearly empty and the injection is complete, the bladder is sized to be received within the slot 206 of the delivery termination member. As a result, the delivery termination member 204 moves radially outward to the position shown in FIG. 88B under the bias of the leaf spring 216. As explained in more detail below, this releases the button 210 from the dispense position and allows it to rise under the bias of the return spring and move toward the post-dispense position as shown in FIG. 88B. As shown in FIG. 88B, the radial outward movement of the delivery termination member also moves the latch tab 208 out of vertical alignment with the button undercut 212, allowing the button 210 to fully rise to the post-dispense position. As the button 210 rises under the bias of the return spring, the injection cannula is retracted into the housing 218 of the injection device.

[0254] Described below are embodiments of the internal components of an injection device that can provide the automatic needle retraction mechanism, premature lockout prevention, and post-injection lockout features summarized above with reference to Figures 88A and 88B.

[0255] Start or pre-launch configuration Figure 89 shows the injection device 200 prior to injection, with the safety sleeve 219 (described above with reference to Figure 83) attached. The injection device button cap 214 is in the start or pre-fire position. The injection device housing 218 includes a retainer 220 and a lid 221 secured together.

[0256] As shown in Figure 90, the button 210 of the injection device is disposed within the boss portion 223 of the holder 220. The elastic bladder 202, which is empty in Figure 90, encases a portion of the outside of the boss portion 223.

[0257] A leaf spring, generally designated 222 in Figure 91, is disposed within the injection device holder. The leaf spring includes a leaf spring, generally designated 216, lockout spring arms 224a-224c, and hook spring arms 226a and 226b. Leaf spring 216 includes a distal end 228, an angled foot tab 232, and an angled biasing tab 234.

[0258] The leaf spring 222 may be formed from metal, although alternative resilient materials such as plastic may be used. Additionally, although three lockout spring arms and two hook spring arms are shown, a different number of each may be used.

[0259] An assembled view of the button 210, leaf spring 222, and delivery termination member 204 with a filled bladder (when the injection device is in the starting or pre-fire configuration) is shown in Figure 92. The latch tab 208 is vertically spaced from the undercut 212 of the button 210. Additionally, the upper portions of the lockout spring arms 224c and 224b slidingly engage the inner surfaces of corresponding lockout blocks 242c and 242b of the button 210. As can be seen in Figure 94, the upper portion of the lockout spring arm 224a similarly engages the button lockout block 242a.

[0260] 93, a return spring 244, preferably a compression coil spring, is positioned between the upper inner surface of button 210 and the retaining portion of the housing, causing button 210 to be forced upward, away from the retaining portion and leaf spring 222, and into a slightly compressed state as shown in FIG.

[0261] As seen in the previous embodiment, the injection cannula 246 is attached to the button 210 and moves downward with the button. As shown in Figure 89, the sharp tip of the injection cannula 246 is safely stored within the housing of the injection device.

[0262] 93, when button 210 is in the start or pre-fire position, hook spring arm 226b engages a step 250b formed on the inner surface of button 210. Hook spring arm 226b is biased at its upper or distal end away from step 250b, but remains engaged with the step due to the upward pressure exerted on button 210 (and step 250b) by return spring 244. Hook spring arm 226a has the same function but features a differently shaped step (which may be part of a continuous step) formed on the inner surface of button 210. As a result, button cap 214 is held in the start or pre-fire position shown in FIGS. 89 and 90 before being depressed to initiate an injection.

[0263] As shown in FIG. 92 , distal end 228 of leaf spring passes through window 254 formed in delivery termination member 204 and is biased to press delivery termination member 204 into the position shown. As shown in FIG. 94 , button 210 is provided with a biasing post 256 that is positioned over biasing tab 234 of leaf spring 216. As a result, when button 210 is depressed downward into the dispensing position (described below), biasing post 256 engages biasing tab 234, thereby further urging distal end 228 of leaf spring in the direction of arrow 258 in FIG. 94 . As a result, distal end 228 of leaf spring acts against window 254, forcing delivery termination member 204 ( FIG. 92 ) radially outward.

[0264] 95, button 210 is also provided with a foot member 262 that is positioned above foot tab 232 of leaf spring 216. This provides a mechanism for locking button 210 in the injection position during injection. When button 210 is depressed to the dispense position described below, foot member 262 engages and clears (i.e., snaps past) foot tab 232. As a result, foot member 262 is positioned below foot tab 232, which prevents the foot member from lifting from the dispense position.

[0265] 88A, the injection device is prepared for dosing / injection by filling the elastic bladder 202 with a fluid medication and securing the bottom of the housing 218 to the patient's skin 272. As a result, the delivery termination member 204 is moved to the position shown in FIG. 88A (and FIG. 92), with the latch tab 208 positioned vertically below the button undercut 212.

[0266] Resume and Dispense Configuration 96, the injection device 200 is placed in the dispensing configuration by removing the safety sleeve 219 (FIG. 89) and then depressing the button cap 214 to the position shown in FIG. 96, which extends the cannula 246 from the bottom of the injection device into the patient and into the injection or dispensing position. As previously mentioned, this places the elastic bladder in fluid communication with the bore of the cannula 246, and the elastic force of the bladder injects the fluid medicament into the patient.

[0267] When the button cap 214 is pushed downward to the position shown in Figure 96, the button 210 moves downward into the injection device housing against the flat spring 222. As a result, as previously described and shown in Figure 97, the biasing post 256 engages the biasing tab 234 of the leaf spring, urging the delivery termination member 204 further toward the radially outward position shown in Figures 88B, 90, 92, and 93. However, as shown in Figure 88A, the expanded elastic bladder 202 prevents the delivery termination member from moving to such a position.

[0268] Furthermore, as shown in FIG. 98 , when the button 210 moves downward, the undercut 212 of the button 210 passes over the latch tab 208 of the delivery end member 204, thereby activating the premature lockout prevention feature of the injection device. More specifically, if the user releases their finger from the button cap 214 after the premature lockout prevention feature has been activated but before the button 210 is fully depressed to the dispensing position, as shown in FIG. 98 , the return spring causes the button to rise, and the undercut 212 of the button 210 engages with the latch tab 208 on the end of the delivery end member 204, placing the button in the resume position shown in FIG. 98 . From this resume position, the button can be fully depressed to the dispensing position, as shown in FIG. 99 .

[0269] As previously mentioned, foot 262 (FIG. 95) of button 210 passes over foot tab 232 of leaf spring 216 as it moves to the position shown in FIG. 99, thereby holding button 210 in the dispense position. When the button is in the dispense position, the undercut of the button is positioned vertically below and spaced from the latch tab of the delivery termination member.

[0270] As the injection nears completion, the elastic bladder shrinks to a size that can be received within the open-end slot (206 in FIGS. 88A and 88B ) of the delivery termination member 204. When this occurs, the biasing force of the leaf spring 216 causes the delivery termination member to move radially outward, as shown in FIG. 88B , causing the latch tab 208 to slide away from the undercut 212 of the button 210. As shown in FIGS. 88A and 88B , the button 210 includes a guide wall 213 disposed adjacent the undercut 212. When the button is in the dispensing position of FIG. 99 , the vertical spacing between the undercut 212 of the button and the latch tab 208 of the delivery termination member is sufficient to allow the latch tab 208 to move over the top of the guide wall 213 as the latch tab moves radially outward to the position shown in FIG. 88B .

[0271] 99, when the delivery termination member is moved radially outward due to the bias of the leaf spring 216, the foot tab 232 of the leaf spring 216 disengages from the foot 262 of the button. As a result, the bias of the return spring 244 (FIG. 93) causes the button 210 to rise to the position shown in FIGS. 88B, 89, and 90, completing the administration of the medication and returning the cannula to the housing of the injection device. As the button 210 rises, the latch tab 208 of the delivery termination member 204 moves vertically upward along the side of the guide wall 213 opposite the side adjacent to the button undercut 212. This reduces the risk of the undercut 212 accidentally engaging the latch tab 208 when the button is raised.

[0272] Pause configuration As mentioned above, it may be desirable to pause an injection after (or before) starting the injection. The injection device can be placed in the pause configuration by depressing the button cap 214 to the position shown in FIG. 100. In this position, the button cap 214 is pressed further into the injection device housing 218 than when the device is in the dispense configuration (FIG. 96). When this occurs, referring to FIG. 101, the undercut 212 of the button 210 moves downward against the biasing force of the return spring 244, further away from the latch tab 208 of the delivery termination member 204 (FIG. 93). Additionally, as shown in FIG. 102, the foot 262 of the cap 210 moves further downward from the leaf spring 216 and foot tab 232.

[0273] When the user wishes to exit the pause mode or pause configuration and resume dispensing / injection, pressure is removed from the button cap 214, causing the biasing force of the return spring to lift the button cap 214 from the position shown in FIG. 100 to the position shown in FIG. 96. As a result, the button foot 262 lifts from the position of FIG. 102 and returns to the position of FIG. 99, re-engaging with the foot tab 232.

[0274] Post-launch lockout configuration 93, when the button 210 is depressed to reconfigure the injection device from the start or pre-fire configuration to the dispense or pause configuration, the button shoulder 250b moves downward and away from the hook spring arm 226b during the button's initial downward movement. As a result, the hook spring arm 226b swings back away from the inner surface of the button 210, and therefore away from the shoulder 250b, so that the hook spring arm 226b does not engage the shoulder 250b when the button 210 is raised after the injection beyond the start or pre-fire position to the post-fire lockout or post-dispense position. The same is true for the hook spring arm 226a. As a result, after the injection, the biasing force of the return spring 244 (FIG. 93) causes the button 210, and thus the button cap 214, to rise above the start or pre-fire position to the post-dispense or post-fire lockout position shown in FIG. 103.

[0275] Figure 104 shows the position of button 210 relative to leaf spring 222 when the button is in the post-fire, locked-out position of Figure 103. As shown in Figure 104, lockout spring arm 224c includes an inwardly angled lockout portion 274c at its upper or distal end, and lockout spring arm 224b similarly includes a lockout portion 274b. As shown in Figure 91, lockout spring arm 224a similarly includes an inwardly angled lockout portion 274a.

[0276] As previously mentioned, button 210 includes lockout blocks 242a, 242b, and 242c that correspond to lockout spring arms 224a, 224b, and 224c, respectively. Lockout blocks 242b and 242c are shown schematically in FIG. 104, while lockout block 242a is shown in FIG. 94. As shown in FIG. 104, the bottom of lockout block 242b includes a notch 276b, and the bottom of lockout block 242c similarly includes a notch 276c. When the button is in the post-fire, locked-out position, notches 276b and 276c align with lockout portions 274b and 274c of lockout spring arms 224b and 224c. As a result, if a user attempts to depress the button cap 214, and therefore the button 210, from the post-fire, locked-out position shown in FIG. 103, notches 276b and 276c engage lockout portions 274b and 274c of the lockout spring arm, preventing downward movement of the button. The same structure and function apply to lockout spring arm 224a (FIG. 91) and lockout block 242a (FIG. 94). As a result, cap button 214 and button 210 are locked in the position shown in FIG. 104, with the cannula remaining safely retracted and enclosed within the injection device housing 218. A lockout is thus provided, which prevents the cannula from extending from the injection device housing and becoming exposed after an injection.

[0277] The premature lockout prevention feature described above for the injection device prevents post-fire lockout by causing hook spring arms 226a and 226b (FIGS. 92-95) to swing away from corresponding shoulders on the inner surface of button 210 when the button is depressed downward from the pre-fire or start position, but not fully down to the dispense position. The injection device state diagram shown in FIG. 105 is helpful in understanding the function and interaction of the post-fire lockout and premature lockout prevention features of the injection device of FIGS. 88A-104.

[0278] As shown in FIG. 105, the injector is in a start or pre-fire state at 280 (FIG. 89). In normal operation, the user presses the injector button until the injector enters the dispense state 284 (FIG. 96), as indicated by line 282a. Alternatively, the user can depress the injector button to move past the dispense state directly to the pause state 286 (FIG. 100), as indicated by line 282b. The user can cycle between the dispense state 284 and the pause state 286 by pressing and releasing the injector button while there is injectable material in the injector bladder, as indicated by lines 287a and 287b. When the injector bladder is empty or nearly empty of injectable material and the injection is complete, as indicated by line 288, the injector transitions to a post-fire lockout state 289 (FIG. 104).

[0279] Continuing to refer to FIG. 105, as indicated by arrows 290a and 290b, very limited depression of the injection device button may occur before the premature lockout prevention feature is activated. When the injection device button is pressed beyond line 278, as represented by lines 292a and 292b, the premature lockout prevention feature is activated as described above. More specifically, line 278 in FIG. 105 corresponds to the undercut 212 of the button 210 snapping past the latch tab 208 of the delivery termination member 204 when the injection device button is pressed downward (with reference to FIG. 98).

[0280] Line 279 in FIG. 105 corresponds to the state where hook spring arms 226a and 226b (FIGS. 92-95) disengage from button 210, activating the post-fire lockout feature. Line 292a represents the injector button being pressed after the premature lockout prevention feature has been activated, but before the post-fire lockout feature has been activated. Releasing the injector button at this point, as shown by line 292a, will raise the button to the resume state 293 (FIG. 98). As shown by line 292c, slightly depressing the injector button from the resume state (not enough to activate the post-fire lockout feature) will return the button to the resume state 293 upon release. As shown by line 292D, pressing the injector button from the resume state will activate the post-fire lockout feature, but not enough to place the injector in the dispense state 284, returning the button to the resume state 293.

[0281] As shown by line 292b in Fig. 105, if the injector button is depressed from the start or pre-fire state 280 to the extent necessary to activate the premature lockout prevention feature, but is released before placing the injector in the dispense state 284, the button will rise to the resume state 293 (Fig. 98). Without the premature lockout prevention feature, lines 292a and 292b would lead to the post-fire lockout state 289 (Fig. 104) rather than the resume state 293, thereby preventing the injector from prematurely locking out. You will be locked out.

[0282] An injection device showing a slight variation of the embodiment described above with reference to Figures 88A-105 is shown in Figures 106A-106D.

[0283] An injection device, generally designated 400, is shown in a starting or pre-fire configuration in Figure 106A. Except for minor differences discussed below, injection device 400 includes the same components and functions as those described above for the embodiment of Figures 88A-105. A delivery termination member, generally designated 404, includes an open-end slot 406 and a latch tab 408. Injection device 400 also includes a button, generally designated 410, which includes a button undercut 412 and is provided with a button cap 414.

[0284] As shown in FIG. 106B, the elastic bladder 402 (not shown in FIG. 106A) expands as it is filled with injection material. The expansion of the bladder forces the delivery termination member 404 to be forced radially inward and held in the position shown in FIGS. 106A and 106B. When the delivery termination member 404 is in the position shown in FIG. 106A, the undercut 412 is positioned vertically above the latch tab 408. Similar to the embodiment described above with reference to FIGS. 88A-105, this provides the injection device 400 with premature lockout prevention, ensuring that the device will not lock out the button 410 if the button is only partially depressed. More specifically, the button cap 414, and therefore the button 410, of the injection device 400 is pressed against the biasing force of the coil return compression spring, extending and deploying the injection cannula from the bottom of the injection device housing. When the button cap 414 is pressed, the button undercut 412 moves downward (clicks past) the latch tab 408, causing the two structures to interlock if the button cap 414 is released before being fully depressed into the dispensing position shown in FIG. 106B.

[0285] As in the embodiment of Figures 88A-106, when the button cap 414 is pressed, a post formed on the button 410 engages a leaf spring (not shown), which presses the delivery termination member 404 radially outward against the expanded bladder.

[0286] When the button cap (and undercut 412) is further depressed downward by the user to the dispensing position shown in FIG. 106B, the button undercut 412 disengages from the latch tab 408. A mechanism such as that described with reference to the embodiment of FIGS. 88A-105 holds the button 410 in the dispensing position when the user releases the button cap 414 and automatically releases the button once dispensing, i.e., injection, is complete. While in the dispensing position, the button 410 can be further depressed downward to a pause position, in which medication flow from the elastic bladder 402 to the injection cannula is interrupted, as described above. This flow resumes when the button cap is released and, as a result, lifted back to the dispensing position by the return spring.

[0287] As medical fluid flows from the elastic bladder of the injection device through the cannula of the injection device and into the patient's body, the diameter of the bladder 402 decreases. As shown in FIG. 106C, when the fluid in the bladder 402 is empty or nearly empty and the injection is complete, the bladder is sized to fit within the slot 406 of the delivery termination member 404. As a result, the bias of the leaf spring causes the delivery termination member 404 to move radially outward to the position shown in FIG. 106C. The radial outward movement of the delivery termination member disengages the latch tab 408 from its vertical position with the button undercut 412, allowing it to unimpede the movement of the button 410 as it fully ascends to the post-fire lockout position.

[0288] 106A, 106C, and 106D, button 410 includes a guide wall 413 disposed adjacent to undercut 412. When the button is in the dispensing position of FIG. 106B, the vertical spacing between the button's undercut 412 and the delivery termination member's latch tab 408 is sufficient to allow latch tab 408 to move over the top of guide wall 413 as latch tab 408 moves radially outward to the position shown in FIG. 106C.

[0289] The radial outward movement of the delivery termination member also releases the button 410 from the dispensing position, causing it to rise under the bias of the return spring and move toward the post-fire locked-out position, as shown in Figure 106D. As the button 410 rises under the bias of the return spring, the injection cannula is retracted into the housing of the injection device.

[0290] 106D, when the button 410 is raised after dispensing, the latch tab 408 of the delivery termination member 404 moves vertically upward along the side of the guide wall 413 opposite the side adjacent to the button undercut 412. This reduces the risk of the undercut 412 accidentally engaging the latch tab 408 when the button is raised.

[0291] An injection device including another alternative embodiment of an automatic needle retraction mechanism is shown in Figures 107A and 107B. As shown in Figures 107A and 107B, the delivery termination member has been omitted for ease of illustration, but the injection device, portions of which are generally designated 300, includes a housing 302 having a cap 304 and a retainer 306 secured together. As with the previous embodiment, the injection device 300 includes a resilient bladder 310 that expands to receive and store medical fluid for injection into a patient. Figure 107A shows the bladder 310 in an empty (or nearly empty) state, while Figure 107B shows the bladder 310 in a full (or nearly full) state.

[0292] With the exception of the automatic needle retraction mechanism described below, the injection device 300 features the same structure and operates in the same manner as described in the previous embodiment.

[0293] 107A and 107B, has a proximal end 312 secured to the bottom inner surface of the housing retainer 306 and a distal end with a hook 314. The latch arm can be integrally molded with the retainer or formed as a separate piece and attached to the retainer.

[0294] The injection device 300 of Figures 107A and 107B may be provided with a delivery termination member that features the same function and general structure as the empty indicator or delivery termination member 114 of Figures 32 and 33 and / or the delivery termination member 204 of Figures 88A and 88B, except that the injection device button foot 262 and foot tab 232 associated with the delivery termination member of Figures 91 and 95 are missing from the delivery termination member of injection device 300.

[0295] As will be explained in more detail below, when the bladder 310 is filled (or nearly filled) with medical fluid, the delivery end member of the injection device 300 engages the latch arm 308 and pushes the hook 314 inward, as indicated by arrow 316 in FIG. 107B, from the position shown in FIG. 107A to the position shown in FIG. 107B.

[0296] 107A and 107B, injection device 300 includes a button 320 that moves between a start or pre-fire position, shown in FIG. 107A, and a dispense position, shown in FIG. 107B. Button 320 includes an undercut 322. As explained in more detail below and shown in FIG. 107B, when bladder 310 is full (or nearly full) and button 320 is pressed into the dispense position shown in FIG. 107B, undercut 322 moves to snap under hook 314 of latch arm 308. As a result, the button, and therefore injection device 300, is locked in the dispense configuration unless injection is paused.

[0297] The injection device 300 is shown in Figure 107A before filling the bladder 310 with fluid, or during the initial introduction of fluid into the bladder 310. As a result, the delivery termination members are in a radially outward position and do not press inward against the latch arm hooks 314. The latch arms are in the position shown in Figure 107A.

[0298] In Figure 107B, the bladder 310 has been filled with medication fluid, causing the delivery termination member to be moved radially inward (against the biasing force of the leaf spring, as in the embodiments of Figures 32-33 and 88A-104) and disposing the latch arm 308, and therefore the hook 314, in the position shown in Figure 107B. The injection device's button 320 has also been pressed, causing the injection device 300 to dispense fluid (i.e., perform an injection). Because the button is pressed and in the dispensing position, the button's undercut 322 is positioned below and engages the latch arm 308's hook 314. As a result, the injection device 300 is locked in the dispensing configuration.

[0299] However, as with the previous embodiment, the user can press the button further inward relative to the injection device housing from the dispense position to move the injection device from the dispense configuration to the pause configuration, suspending the injection. When the user releases the button, the injection device returns to the dispense configuration shown in Figure 107B to complete the injection.

[0300] As in the previous embodiment, as medical fluid flows from the elastic bladder of the injection device through the cannula of the injection device and into the patient, the diameter of the bladder decreases. When the liquid in the bladder is empty or nearly empty, the diameter of the bladder is sized to fit within the slot (such as 206 in FIGS. 88A and 88B ) in the delivery termination member. When this occurs, as in the previous embodiment, the delivery termination member 324 moves radially outward due to the bias of the leaf spring described above. This causes the latch arm 208 to return to the position shown in FIG. 107A , disengaging the latch arm hook 314 from the undercut 322 of the button 320. Thus, the bias of the return spring causes the button 320 to rise to the position shown in FIG. 107A (as in the previous embodiment), and the injection cannula is withdrawn from the patient and retracted into the injection device housing 302.

[0301] The injection device 300 may also include a post-injection lockout feature as described above with respect to the embodiment of Figures 88A-104, which prevents the button 320 from being pressed after an injection and prevents the cannula from being deployed after an injection.

[0302] The present invention has been described with reference to specific embodiments for purposes of illustration only, and not limitation. It is to be understood that the scope of the present invention is not limited solely to the illustrated embodiments or their equivalents, but applies broadly to different embodiments of construction and use, some of which will be readily apparent upon reading this specification, and others of which will become apparent only after some degree of research and / or development.

Claims

1. A wearable medical fluid injection device, comprising: Housing and an injection needle movable between a retracted position within the housing and an injection position extending from the housing; an actuator associated with the needle for moving the needle between the retracted position and the injection position; a resilient bladder within the housing for containing medical fluid for injection through the needle when the needle is in the injection position; a delivery termination member biased to move from a first position toward a second position within the housing; The delivery termination member (i) configured to engage the bladder when the bladder is substantially filled with medical fluid, such that the bladder prevents the delivery termination member from moving from the first position to the second position; (ii) configured to disengage from the bladder when substantially emptied of medical fluid, allowing the delivery termination member to move from the first position to the second position; the end-of-delivery member is operatively associated with the actuator such that, when in the first position, the end-of-delivery member holds the needle in the injection position and, when in the second position, the actuator allows the actuator to move the needle to the retracted position to provide an end-of-delivery indication; a premature lockout prevention system including an engagement surface of the actuator and an engagement surface of the delivery termination member, the engagement surface of the actuator and the engagement surface of the delivery termination member comprising: (i) when the delivery termination member is in the first position, engagement between an engagement surface of the actuator and an engagement surface of the delivery termination member is aligned to limit movement of the engagement surface of the actuator relative to the engagement surface of the delivery termination member; (ii) an injection device, wherein when the delivery termination member is in the second position, the engagement surface of the delivery termination member is misaligned so as not to interfere with the movement of the engagement surface of the actuator.

2. The actuator is a button mounted within the housing, the button being movable between a raised position corresponding to the retracted position of the needle and a depressed position corresponding to the injection position of the needle; a return spring configured to bias the button to the raised position; The injection device of claim 1 , wherein the actuator engagement surface is attached to the button.

3. 3. The injection device of claim 2, wherein the actuator engagement surface is an undercut formed in the button.

4. The injection device of claim 2 , wherein the end-of-delivery member includes a latch tab that includes an engagement surface of the end-of-delivery member.

5. 3. The injection device of claim 2, wherein the actuator engagement surface is an undercut formed in the button, and the delivery termination member includes a latch tab that includes the delivery termination member engagement surface.

6. 3. The injection device of claim 2, further comprising a leaf spring configured to bias the delivery end member from the first position toward the second position, wherein the button is configured (i) to engage with the leaf spring when the delivery end member is in the first position and the button is in the depressed position, and (ii) to disengage from the leaf spring and move the button to the raised position when the delivery end member is in the second position.

7. 7. The injection device of claim 6, wherein the delivery termination member comprises a slot configured to slide over the bladder when it is substantially empty of medical fluid.

8. 8. The injection device of claim 7, wherein the bladder includes an exit port, and the slot of the delivery termination member is configured to slide over a portion of the bladder adjacent the exit port when the bladder is substantially emptied of medication liquid.

9. The injection device of claim 7 , wherein the slot has an open end.

10. 7. The injection device of claim 6, wherein the button comprises a post configured to engage with the leaf spring such that when the button is in a depressed position, the leaf spring biases the delivery end member toward the second position.

11. 3. The injection device of claim 2, wherein the button moves between the raised position and the depressed position in a direction substantially perpendicular to a direction of movement of the delivery termination member when the delivery termination member moves between the first position and the second position.

12. 12. The injection device of claim 11, further comprising a foot tab operatively connected to the delivery termination member, wherein the button includes a foot, and the foot tab and the foot are configured such that (i) the foot engages the foot tab when the delivery termination member is in the first position and the button is in the depressed position, and (ii) the button disengages from the foot tab when the delivery termination member is in the second position so that the button is moved to the raised position by the return spring.

13. 3. The injection device of claim 2, wherein the button is further movable relative to the housing to a post-injection lockout position in which the injection needle is further retracted into the housing, the button comprising a lockout block and further comprising a lockout spring arm fixed within the housing, the lockout spring arm configured to engage with the lockout block when the button is raised to the post-injection lockout position.

14. 14. The injection device of claim 13, wherein the button includes a shoulder and further comprises a hook spring arm secured within the housing, the hook spring arm configured to engage the shoulder when the button is in a raised position so as to prevent the button from moving to the post-injection lockout position before moving to the depressed position.

15. the delivery termination member includes a latch tab as an engagement surface of the delivery termination member, and the button includes an undercut as an engagement surface of the actuator; 3. The injection device of claim 2, further comprising a latch arm fixed within the housing, the latch arm having a hook, and the latch arm, the hook, and the delivery termination member are configured such that (i) when the delivery termination member is in the first position and the button is in a depressed position, the latch arm engages with the delivery termination member and the hook engages with the undercut, and (ii) when the delivery termination member is in the second position, the hook disengages from the undercut and the button is moved to the raised position by the return spring.

16. 16. The injection device of claim 15, wherein the button is further movable relative to the housing to a post-injection lockout position in which the injection needle is further retracted into the housing, the button comprising a lockout block and further comprising a lockout spring arm fixed within the housing, the lockout spring arm configured to engage with the lockout block when the button is raised to the post-injection lockout position.

17. 17. The injection device of claim 16, wherein the button comprises a shoulder and further comprises a hook spring arm secured within the housing, the hook spring arm configured to engage the shoulder when the button is in a raised position so as to prevent the button from moving to the post-injection lockout position before moving to the depressed position.

18. 16. The injection device of claim 15, further comprising a leaf spring configured to bias the delivery end member from the first position toward the second position, wherein the button is configured (i) to engage with the leaf spring when the delivery end member is in the first position and the button is in a depressed position, and (ii) to disengage from the leaf spring when the delivery end member is in the second position, causing the button to move to the raised position.

19. 20. The injection device of claim 18, wherein the delivery termination member comprises a slot configured to slide over the bladder when it is substantially empty of medical fluid.

20. 20. The injection device of claim 19, wherein the bladder includes an exit port, and the slot of the delivery termination member is configured to slide over a portion of the bladder adjacent the exit port when the bladder is substantially emptied of medical fluid.

21. 21. The injection device of claim 20, wherein the slot has an open end.

22. 20. The injection device of claim 19, wherein the slot has an open end.

23. 20. The injection device of claim 18, wherein the button comprises a post configured to engage with the leaf spring such that when the button is in the depressed position, the leaf spring biases the delivery end member toward the second position.

24. 16. The injection device of claim 15, wherein the button moves between the raised position and the depressed position in a direction substantially perpendicular to a direction of movement of the delivery termination member when the delivery termination member moves between the first position and the second position.

Images