Drug delivery device safety system

Abstract

A drug delivery device is disclosed that includes a housing, a product container disposed within the housing, a plunger rod partially disposed within the product container, and a thumb pad configured to receive a portion of the plunger rod, wherein the thumb pad and plunger rod are configured to transition from a first state to a second state, wherein in the first state, the plunger rod is prevented from moving in a proximal direction and wherein in the second state, the plunger rod is free to move in the proximal direction.

Description

[Technical field]

[0001] The present disclosure is directed to a safety system for a drug delivery device (e.g., a prefilled syringe) and a method of use thereof. [Background technology]

[0002] Drug delivery devices (e.g., prefilled syringes, auto-injectors, or other suitable drug delivery devices) are routinely used to deliver liquid drug substances. Various safety concerns may arise before, during, and after use of the drug delivery device. To address such concerns, conventional safety devices have been developed. Conventional safety devices may include active safety mechanisms. In such devices, the user is required to actively perform a specific action to trigger the safety mechanism. It may be difficult for a user to properly activate the safety mechanism and at the same time properly utilize the drug delivery device to inject the drug substance into themselves or another person. In contrast to these active safety devices, passive safety devices have been developed that do not require the user to perform any additional and / or separate actions to trigger the safety mechanism during and / or after use of the drug delivery device.

[0003] In passive safety systems, concerns may still exist for user safety and proper use of the drug delivery device. For example, there may be premature drainage of liquid, accidental needle stick before and / or after injection, and / or premature lockout before the end of administration. Passive safety mechanisms should be configured for proper and safe use before, during, and after injection. Summary of the Invention

[0004] The present disclosure describes a drug delivery device comprising a housing, a product container disposed within the housing, a plunger rod partially disposed within the product container, and a thumb pad configured to receive a portion of the plunger rod, wherein the thumb pad and plunger rod are configured to transition from a first state to a second state, wherein in the first state, the plunger rod is prevented from moving in a proximal direction and wherein in the second state, the plunger rod is free to move in the proximal direction.

[0005] Various embodiments of the device may include one or more of the following aspects. The thumb pad may include an extension that projects distally from the thumb pad. The housing has a shoulder, and in a first state, the shoulder may project radially inward to block movement of the product container. In a second state, the extension of the thumb pad may be configured to deflect the shoulder radially outward to allow the product container to move in a proximal direction. The product container and a needle attached to a distal end of the product container may be retracted proximally into the housing such that the needle is located proximate to a distal end of the housing. A distance that the product container retracts proximally into the housing in the second state may be substantially equal to a length of the needle that extends distally from the housing in the first state. A proximal end portion of the plunger rod may include a flange, and the thumb pad may include a recess configured to receive the flange. The plunger rod may abut an inner distal surface of the thumb pad in the second state. An audible feedback may be generated when a portion of the plunger rod abuts an inner distal surface of the thumb pad in the second state. The housing may include a surface configured to deflect a portion of the thumb pad outwardly when transitioning to the second state to release a proximal portion of the plunger rod. The housing may include a notch configured to engage a portion of the thumb pad to couple the thumb pad to the housing in the second state. The plunger rod may include a first portion and a second portion, the first portion having a diameter greater than a diameter of the second portion such that in the first state the first portion is proximate to the second portion and in the second state the second portion is folded inside the first portion. The device may include a rotor configured to be located proximate to a proximal end of the product container in the first state and configured to surround the proximal end of the product container in the second state. The plunger rod may include a first portion and a second portion, a distal end of the second portion coupled to a proximal end of the first portion, and the housing may include a proximal extension, and in a first state, the proximal extension abuts the distal end of the first portion to prevent the product container from moving proximally away from the housing.In the second state, the proximal extension may deflect away from the distal end of the first portion to allow the product container to move proximally away from the housing and into the thumb pad. The proximal end of the housing may include a rear cap configured to surround the proximal end of the product container.

[0006] The present disclosure also describes a drug delivery device comprising a housing, a product container disposed within the housing, a needle extending from a distal end of the product container, a plunger rod for administering the product from the product container, the plunger rod including a first recess at a distal portion of the plunger rod and a second recess at a proximal portion of the plunger rod, a blocking component at a proximal end of the housing, the plunger rod being slidably received within the blocking component, the blocking component including a flexible arm, and a needle cover at least partially disposed within the housing.

[0007] Various embodiments of the device may include one or more of the following aspects: The device is configured to transition from a first state in which the distal end of the needle cover abuts the flexible arm and the flexible arm is aligned with the first recess to a second state in which the flexible arm is deflected radially outward, and to a third state in which the flexible arm is aligned with the second recess and the distal end of the needle cover is located proximal to the flexible arm. The second recess may have a smaller diameter than the first recess. The housing may include a ledge for abutting a portion of the needle cover to prevent proximal movement of the needle cover into the housing. In the first state, the needle cover may extend distally of the housing to cover the needle. In the second state, the proximal end of the needle cover may abut a distal portion of the blocking component. In a first state, the flexible arm may limit movement of the plunger rod, and in a second state, the deflected flexible arm may allow movement of the plunger rod. The device may include an inner rod configured to be secured within the plunger rod. The inner rod may include a distal block that abuts a portion of the plunger rod to prevent the plunger rod from moving in a distal direction. The distal end of the plunger rod may include a flexible arm configured to abut a portion of the inner rod to prevent the plunger rod from moving in a distal direction. The plunger rod may include a flexible section, and in the first state, the distal block may prevent the flexible section from compressing, and in the second state, the distal block may move away from the flexible section to allow the flexible section to compress. The housing may include a finger flange and a button mechanism, and the button mechanism may be configured to abut a portion of the plunger rod in the first state and deflect away from the plunger rod in the second state.

[0008] The present disclosure also describes a drug delivery device comprising a housing, a plunger rod, a needle cover disposed at least partially within the housing, and a rotating component having a track extending along an outer surface of the rotating component, wherein a portion of the plunger rod extends through a central region of the rotating component, the rotating component being located radially inward of a proximal portion of the needle cover, and a protrusion of the needle cover configured to engage the track of the rotating component and move along the track of the rotating component as the device transitions from a first state, to a second state, and to a third state.

[0009] Various embodiments of the device may include one or more of the following aspects: The device further comprises a product container containing a liquid drug substance, and a stopper disposed within the product container, the stopper being moved distally by distal movement of the plunger rod, and in a first state, the protrusion may engage a first end of the track to limit distal movement of the plunger rod. In a second state, the protrusion may engage an intermediate portion of the track to allow distal movement of the plunger rod, and the needle cover may be positioned further proximally within the housing relative to the position of the needle cover in the first state. In a third state, the protrusion may engage a second end of the track, and the needle cover may be positioned further distally within the housing relative to the position of the needle cover in the second state and extend from the distal end of the housing. In the third state, the needle cover may be positioned further distally within the housing relative to the position of the needle cover in the first state, and the needle cover may extend from the distal end of the housing in the first state and the third state.

[0010] The present disclosure also describes a drug delivery device comprising a housing including a flexible tab, a syringe disposed within the housing, a plunger rod including a stopper for administering a product contained within the syringe, a needle cover disposed at least partially within the housing, the needle cover including a notch, and a ring including a ledge, the ring positioned around a proximal end of the syringe, the device configured to transition between a first state, a second state, and a third state, where in the second state the needle cover is located further proximally within the housing compared to the first state and the third state, and the proximal end of the needle cover is configured to push the flexible tab of the housing outward, and the notch of the needle cover engages the ledge of the ring.

[0011] Various embodiments of the device may include one or more of the following aspects: In the third state, the needle cover and the ring may be located distal to the flexible tab, and the flexible tab may limit movement of the needle cover in a proximal direction. In the first state, the needle cover may be located distal to the ring.

[0012] The present disclosure also describes a drug delivery device comprising a housing, a product container disposed within the housing, and a plunger rod partially disposed within the product container, the plunger rod including a first portion and a second portion, the first portion configured to receive the second portion, the first portion and the second portion of the plunger rod configured to transition from a first state to a second state, wherein in the first state, the second portion of the plunger rod is prevented from moving in a proximal direction and wherein in the second state, the second portion of the plunger rod is free to move in the proximal direction.

[0013] Various embodiments of the device may include one or more of the following aspects: The portion may include a thumb pad. The thumb pad may include a recess configured to receive the second portion of the plunger rod. In the second state, the second portion of the plunger rod may move proximally into the first portion of the plunger rod. The plunger rod may include a flexible portion. The second portion of the plunger rod may be removably coupled to the first portion of the plunger rod. [Brief description of the drawings]

[0014] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various examples and, together with the description, serve to explain the principles of the disclosed examples and embodiments. Aspects of the present disclosure may be implemented in conjunction with the embodiments illustrated in the accompanying drawings, which show different aspects of the present disclosure. Where appropriate, reference numerals indicating similar structures, components, materials, and / or elements in different figures are similarly labeled. It is understood that various combinations of structures, components, and / or elements other than those specifically shown are contemplated and are within the scope of the present disclosure.

[0015] Moreover, many embodiments are described and illustrated herein. The present disclosure is not limited to any single aspect or embodiment thereof, nor to any combination and / or permutation of such aspects and / or embodiments. Moreover, each of the aspects of the present disclosure and / or its embodiments can be used alone or in combination with one or more of the other aspects and / or embodiments of the present disclosure. For the sake of brevity, certain permutations and combinations are not separately described and / or illustrated herein. In particular, an embodiment or implementation described herein as "exemplary" should not be construed as being preferred or advantageous over other embodiments or implementations, for example, but rather is intended to reflect or indicate that the embodiment(s) are "exemplary" embodiment(s). [Figure 1A-1B] 1A-1B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Fig. 2A-2F] 2A-2F illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 1A-1B. [Figure 3A-3B] 3A-3B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 4A-4D] 4A-4D illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 3A-3B. [Figure 5A-5D] 5A-5D illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 3A-3B. [Figure 6A-6B] 6A-6B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 7A-7F] 7A-7F illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 6A-6B. [Figure 8A-8B] 8A-8B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 9A-9D] 9A-9D illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 8A-8B. [Figure 10A-10B] 10A-10B illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 8A-8B. [Figure 11] FIG. 11 illustrates an exemplary safety device and its components according to an embodiment of the present disclosure. [Figures 12A-12C] 12A-12C illustrate additional aspects and embodiments of the exemplary safety device of FIG. [Figure 13A-13B] 13A-13B illustrate additional aspects and embodiments of the exemplary safety device of FIG. [Figures 14A-14C] 14A-14C illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 15A-15D]15A-15D illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 14A-14C. [Figure 16A-16B] 16A-16B illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 14A-14C. [Figures 17A-17G] 17A-17G illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 18A-18B] 18A-18B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 19A-19B] 19A-19B illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 18A-18B. [Figures 20A-20C] 20A-20C illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 18A-18B. [Figures 21A-21C] 21A-21C illustrate additional aspects and embodiments of the exemplary safety device of FIGS. 18A-18B. [Fig. 22A-22B] 22A-22B illustrate additional aspects and components of an exemplary safety device according to an embodiment of the present disclosure. [Figure 23A-23B] 23A-23B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figures 24A-24C] 24A-24C illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Diagram 25] FIG. 25 illustrates an exemplary safety device and its components according to an embodiment of the present disclosure. [Figure 26A-26B] 26A-B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 27A-27B] 27A-B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Fig. 28A-28B] 28A-B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Figure 29A-29B] 29A-29B illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Fig. 30A-30D] 30A-30D illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. [Diagram 31] FIG. 31 illustrates an exemplary safety device and its components according to an embodiment of the present disclosure. [Fig. 32A-32F] 32A-32F illustrate an exemplary safety device and its components, according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] As used herein, the terms "comprises," "comprising," "includes," "including," or other similar terms are intended to include a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements can include not only those elements, but also other elements not expressly listed or other elements inherent to such process, method, article, or apparatus. The term "or" is intended to be inclusive and mean that a process, method, article, or apparatus that includes a list of elements may include any combination or all of the elements. The term "exemplary" is used in the sense of "exemplary" rather than "ideal." In addition, terms such as "first," "second," and the like are used herein not to denote any order, quantity, or importance, but rather to distinguish one element or structure from another. Furthermore, the terms "a" and "an" are used herein not to denote a limitation of quantity, but rather to denote the presence of one or more of the referenced items.

[0017] The term "distal end" or any variation thereof refers to the portion of the device that is the drug delivery end. Conversely, the term "proximal end" or any variation thereof refers to the portion of the device that is the actuation end. Additionally, the terms "about," "substantially," and "approximately" as used herein generally mean + / - 10% of the stated value.

[0018] Among other things, for simplicity and clarity of explanation, certain aspects of the figures show schematic structures and / or methods of construction of various embodiments. Descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring other features. Elements in the figures are not necessarily drawn to scale, and dimensions of some features may be exaggerated relative to other elements to improve understanding of the illustrative embodiments. For example, those skilled in the art will appreciate that side views are not drawn to scale and should not be viewed as depicting proportional relationships between separate components. Side views are provided to help illustrate the various components of the depicted assemblies and to show their relative positional relationships.

[0019] Reference will now be made in detail to the examples of the present disclosure, which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Various safety concerns may arise with the use of drug delivery devices. Safety issues and concerns may arise before, during, and / or after use, i.e., before, during, and / or after injection of a product, e.g., a liquid medicament, from the drug delivery device. For example, premature ejection of product may occur if the device components are not secured and / or locked in the proper pre-injection position. Exposed needles may cause accidental needle sticks during injection if the device is inadvertently removed from the injection site, and / or after injection if the device is removed from the injection site and discarded. Exposed needles may also adversely affect users with needle phobia and / or anxiety regarding needles. In addition, there may be concerns that the user will insert and / or inject the needle at an incorrect depth into the injection site.

[0020] To address such concerns, conventional safety devices have been developed. Conventional safety devices may include active safety mechanisms. An active safety mechanism refers to a mechanism in which a user is required to actively perform a specific action to trigger the safety mechanism. It may be difficult for a lay user, i.e., a user without medical training, to properly activate an active safety mechanism while simultaneously properly injecting a drug into himself or another person. Furthermore, an active safety mechanism may not have any effect if the user fails to trigger the safety mechanism. To address such issues, passive safety mechanisms have been developed. Devices that include passive safety mechanisms do not require the user to perform any additional and / or separate actions to trigger the safety mechanism before, during, and / or after use of the device. However, other concerns may arise regarding the use of passive drug delivery devices. For example, if the user accidentally removes the device from the injection site, the passive safety mechanism may automatically activate before the administration is completed. In such cases, the user is unable to complete the administration and must obtain another device.

[0021] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to drug delivery devices, and in particular to devices that passively activate a safety mechanism during and / or after injection of a medication from a product container, i.e., a syringe.

[0022] FIG. 1A shows an exterior view of device 10. Device 10 may be configured to hold any commercially known product container 12 (e.g., a syringe or other suitable drug delivery device). Device 10 may include a housing 14, a plunger rod 16, and a thumb pad 20. FIG. 1B shows an interior view of device 10, where housing 14 may be configured to accommodate container 12. In the embodiment shown in FIG. 1B, container 12 may be a syringe, e.g., a prefilled syringe. Housing 14 may include an inwardly protruding shoulder 28. As shown in FIG. 1B, shoulder 28 may be located at a proximal portion of housing 14 and abut a proximal end of container 12 when accommodated within housing 14. Plunger rod 16 may include a stopper 18 for expelling product from container 12 and a flange 26 for coupling to thumb pad 20. With reference to FIG. 1B, the stopper 18 may be positioned at the distal end of the plunger rod 16 and the flange 26 may be positioned at the proximal end of the plunger rod 16.

[0023] As described in detail below, the plunger rod 16 may abut and / or releasably couple to a portion of a syringe within the housing 14, such as the piston of the syringe. In some embodiments, the plunger rod 16, thumb pad 20, and syringe may be locked together during an injection to transmit the user's force on the plunger rod 16 to the piston of the syringe. After an injection is completed, the plunger rod 16 may be separated from the syringe. After the plunger rod 16 is separated from the syringe, the thumb pad 20 may couple to the housing 14 and prevent the thumb pad 20, plunger rod 16, and / or syringe from moving in a proximal direction. As the thumb pad 20 moves distally relative to the housing 14, the spring 13 may move the syringe proximally within the housing 14.

[0024] Various components may be utilized to move the plunger rod 16 and / or syringe and then lock the thumb pad 20, plunger rod 16, and / or syringe within the housing 14. In some embodiments, the thumb pad 20 may include a deflectable tab 22 and a distal extension 24. As shown in FIG. 2B, the deflectable tab 22 may include a recess 23. The recess 23 may be releasably coupled to a flange 26 of the plunger rod 16. In some embodiments, the deflectable tab 22 and the recess 23 may be formed continuously or around a majority of the inner portion of the thumb pad 20. In other words, the deflectable tab 22 and the recess 23 may be formed in the thumb pad 20 to surround the flange 26. In other embodiments, the thumb pad 20 may include two or more deflectable tabs 22 and recesses 23. For example, thumb pad 20 may include two flexible tabs, three flexible tabs, or four flexible tabs, each with a recess 23. In configurations having more than one flexible tab 22 and recess 23, the tabs may be equally spaced from one another. For example, if thumb pad 20 includes four flexible tabs, each of the tabs may be approximately 90 degrees from one another. Additionally, each flexible tab may include a recess 23 for releasably coupling to a portion of flange 26.

[0025] In some embodiments, the thumb pad 20 may include two or more distal extensions 24. For example, the thumb pad 20 may include two, three, four, or more distal extensions 24. In configurations having two or more distal extensions 24, the distal extensions may be equally spaced apart from one another. For example, if the thumb pad 20 includes four distal extensions 24, each of the distal extensions may be approximately 90 degrees from one another. In some embodiments, a single distal extension may extend continuously or at least partially around the thumb pad 20.

[0026] Prior to injection, the plunger rod 16 may be fully extended from the proximal end of the housing 14 (FIG. 1B). In such a configuration, the container 12 (e.g., a filled syringe) and the plunger rod 16 may not be removed from the device 10. Various components may prevent removal of the plunger rod 16 from the device 10. For example, the arm 36a of the thumb pad 20 may lock into the interior of the housing 14 to prevent removal of the plunger rod 16. With reference to FIGS. 2A-2B, to initiate injection of the product from the container 12, the user may press down on the thumb pad 20 to move the thumb pad 20 and the plunger rod 16 distally toward the housing 14. After the product is fully expelled from the container 12 at the end of the injection dose, the thumb pad 20 may abut the proximal end of the housing 14 (FIG. 2B). The proximal end of the housing 14 may include a collar 30 aligned with the flexible tab 22. As shown in FIG. 2B, collar 30 may have a beveled surface configured to abut flexible tab 22 and deflect it outwardly away from flange 26 when an injection dose is completed. Flexible tab 22 may also include a beveled surface configured to abut the beveled surface of collar 30 to facilitate deflection of flexible tab 22. Thumb pad 20, tab 22, and recess 23 may separate from flange 26, releasing plunger rod 16. FIG. 2A also shows arm 36a of thumb pad 20, which is described in more detail below with reference to the lockout feature of device 10.

[0027] Also, as shown in FIG. 2B, when the thumb pad 20 abuts against the housing 14 upon completion of the injection dose, the distal extension 24 of the thumb pad can contact the shoulder 28 of the housing 14 and deflect the shoulder 28 of the housing 14 outwardly away from the plunger rod 16. FIG. 2C shows the distal extension 24 and shoulder 28 before they are moved into contact with each other, and FIG. 2D shows the distal extension 24 of the thumb pad 20 as it begins to contact the shoulder 28. Deflecting the shoulder 28 outwardly away from the plunger rod 16 and the proximal end of the container 12 releases the container 12 and allows movement of the container 12 in a proximal direction. In some embodiments, a spring 13, e.g., a spring shroud, can abut a portion of the container 12 within the housing 14 to push the container 12 in a proximal direction when the container 12 is released from the shoulder 28. For example, the at least partially compressed spring 13 may contact a distal surface of the flange of the container 12, and upon deflecting the shoulder 28 outwardly so that it no longer abuts the container 12, the spring may push the distal surface of the flange of the container 12, and thus the entire container 12, in a proximal direction. The inclusion of a spring may provide a lockout feature to the device 10 to prevent reuse of the device. A spring may surround the container 12 within the housing 14, or one or more springs may be disposed adjacent the container 12 and abut a distal surface of a portion of the container 12.

[0028] FIG 2E shows device 10 prior to lockout of device 10, with thumb pad 20 initially abutting the proximal end of housing 14, and FIG 2F shows device 10 locked out, with plunger rod 16 and flange 26 seated within thumb pad 20 such that flange 26 abuts distal inner wall 32 of thumb pad 20. Once plunger rod 16 and flange 26 are released from recess 23 of flexible tab 22 and the distal end of reservoir 12 is released from shoulder 28, plunger rod 16, flange 26, and reservoir 12 can move proximally toward distal inner wall 32 of thumb pad 20 (FIG 2F).

[0029] In some embodiments, the thumb pad 20 may include one or more arms, for example, arms 36a and 36b, that extend distally into the interior of the housing 14 when the thumb pad 20 is depressed. The distal ends of the arms 36a, 36b may project radially outwardly away from the container 12, and the arms 36a, 36b may be biased radially outwardly. The housing 14 may include a pair of notches 34a, 34b. When the thumb pad 20 abuts the distal end of the housing 14, releasing the flange 26, plunger rod 16, and container 12, the projections on the distal ends of the arms 36a, 36b may align with the notches 34a, 34b and may be deflected outwardly to engage the notches 34a, 34b (FIG. 2E). The engagement of the distal ends of arms 36a, 36b with notches 34a, 34b can maintain thumb pad 20 in place when flange 26 moves proximally against distal inner wall 32 of thumb pad 20 (FIG. 2F), and also functions to lock thumb pad 20 to housing 14, preventing reuse of device 10.

[0030] In some embodiments, multiple arms may extend distally from the thumb pad 20. For example, the thumb pad 20 may include two, three, four, or more arms 36a, 36b. In configurations with more than two arms, the arms may be equally spaced apart from one another. For example, if the thumb pad 20 includes four arms, each arm may be approximately 90 degrees from one another. If the thumb pad 20 includes two arms, the arms may be approximately 180 degrees from one another. Additionally, the housing 14 may include a complementary number of notches aligned with the multiple protrusions on the distal ends of the arms when the thumb pad 20 is in its distal-most position. In some embodiments, a single arm may extend from the thumb pad 20 and the housing 14 may include a single notch aligned with that arm. In some embodiments, the thumb pad 20 may include two arms and the housing 14 may include two notches, one aligned with each arm, and so on. Although the notches 34a, 34b are shown as extending through the wall of the housing 14, it is envisioned that the notches 34a, 34b may be recesses or grooves that may not extend completely through the housing 14. In embodiments in which the notches are grooves, one or more grooves may be located along the arms on the thumb pad 20, or a single groove may extend around the inner wall of the housing 14.

[0031] The embodiment of Figures 1A-2F shows a device with a passive safety mechanism that can be activated when the user is nearing the end of administration, i.e., when a significant amount of product has been completely expelled from the container 12. The passive safety mechanism of Figures 1A-2F can allow the container 12 and needle 2 (Figure 1B) to move proximally into the housing 14 at the end of administration, such that the needle 2 is fully retracted into the housing 14 to prevent accidental needle sticks after injection. The container 12 and needle 2 are not moved proximally into the housing 14 until the injection is completed and the thumb pad 20 is pressed against the proximal end of the housing 14 to release the flange 26 and the container 12. As shown in Figures 1A-1B, only a portion of the needle 2 is visible to the user. This may prevent needle phobia and needle-related anxiety compared to conventional drug delivery devices with exposed needles. Additionally, exposing only a portion of needle 2 may enable use of device 10 without any pre-injection steps, such as pinching the skin to alter the injection depth to compensate for the longer needle length compared to the exposed needle 2 of device 10. Device 10 may be sized such that only a portion of the needle is exposed and the initial position of container 12 within housing 14 is calibrated such that the length of the exposed portion of needle 2 indicates the desired insertion depth of needle 2.

[0032] In some embodiments, device 10 may include a feedback mechanism. Device 10 may include a visual feedback mechanism, for example, when thumb pad 20 and housing 14 are locked together and needle 2 is retracted into housing 14 so that needle 2 is not visible by the user when device 10 is pulled away from the injection site. In some examples, device 10 may include an optional opening 40 (FIG. 1B) for viewing container 12 and the movement of plunger rod 16 and stopper 18 within container 12. In some aspects, device 10 may include an audible feedback mechanism, for example, an audible "clicking" sound, when thumb pad 20 and housing 14 interlock and / or flange 26 abuts distal inner wall 32 of thumb pad 20. In some embodiments, device 10 may include tactile feedback, e.g., a snap or vibration, when thumb pad 20 and housing 14 interlock and / or when flange 26 abuts distal inner wall 32 of thumb pad 20.

[0033] Device 10 may be of any suitable size and shape for holding or partially holding product container 12 and / or supporting and holding plunger rod 16 and stopper 18 within product container 12. Thumb pad 20 may be of any suitable size and shape for abutting and locking against apparatus 10. Components of thumb pad 20, including flexible tab 22 and recess 23, may be of any suitable size and shape for receiving flange 26. Notches 34a, 34b may be of any suitable size and shape for receiving arms 36a, 36b.

[0034] In other embodiments, the device 10 may include a rear cap 170 (FIGS. 17A and 17B). As shown in FIG. 17B, the rear cap 170 may be shaped and configured to fit inside the proximal end of the housing 14. The rear cap 170 may have a substantially circular shape. The proximal end of the rear cap 170 may abut the proximal end of the housing 14 such that the rear cap 170 may be secured within the housing 14. With reference to FIG. 17B, the rear cap 170 may include a rear cap recess 172 for receiving a portion of the syringe 12. For example, the proximal portion of the syringe 12 may fit into the rear cap recess 172 of the rear cap 170. The thumb pad 20 of the device 10 may include a flexible tab 22. In some examples, the thumb pad 20 may include a plurality of flexible tabs 22. The flexible tab 22 may include a recess 23 configured to receive the flange 26 of the plunger rod 16. The thumb pad 20 may also include a proximal extension 24. In some examples, the thumb pad 20 may include multiple proximal extensions 24. FIG 17C shows a rotated view of the device 10 of FIG 17B. Referring to FIG 17C, the plunger rod 16 includes multiple ridges 16a and portions of the rear cap 170 may abut against portions of the ridges 16a.

[0035] During use, the user can push the thumb pad 20 in a distal direction toward the housing 14. Similar to the mechanism described with reference to FIGS. 2A and 2B, with reference to FIGS. 17D and 17E, as the thumb pad 20 is pushed toward the housing 14, a portion of the proximal end of the housing 14 can abut against the flexible tab 22. The flexible tab 22 can flex away from the flange 26, allowing the plunger rod 16 and the thumb pad 20 to separate. FIG. 17E shows a rotated view of the device 10 of FIG. 17D. With reference to FIG. 17F, at the end of administration, the distal end of the extension 24 can click into the interior of the housing 14. For example, the housing 14 can include a notch 174 that receives the distal end of the extension 24. When the distal end of extension 24 snaps into notch 174, the distal end of extension 24 can push a portion of rear cap 170 inward toward plunger rod 16, allowing rear cap 170 to move proximally into thumb pad 20. Device 10 may include an actuator, e.g., a spring (not shown), under rear cap 170. The actuator can be configured to push rear cap 170 into thumb pad 20 when a portion of rear cap 170 is pushed inward toward plunger rod 16. FIG. 17G shows a rotated view of device 10 of FIG. 17F.

[0036] 18A and 18B show an alternative embodiment of the device 10. FIG. 18A shows a front external view of the device 10, and FIG. 18B shows a side external view of the device 10. The housing 14 of the device 10 may include a finger flange 15. The finger flange 15 may be located at a proximal end of the housing 14 and extend away from the plunger rod 16. The finger flange 15 may be shaped or configured to be properly held by a user and to be properly operable with a syringe. For example, the finger flange 15 may be designed to meet safety requirements and required needle distance requirements. Referring to FIG. 18B, the housing 14 may include a rear cap 190. In this embodiment, the rear cap 190 may be disposed at a proximal end of the housing 14. The rear cap 190 may include a hook portion 192 extending proximally. As shown in FIG. 18B, the rear cap 190 may include at least two hook portions 192. The hook portion 192 may seat against a recessed portion 180 (shown in detail in FIGS. 19A and 19B ) of the plunger rod 16. The hook portion 192 may hook onto, or seat on, a proximal surface of the recessed portion 180.

[0037] 19A and 19B show cross-sectional views of the device 10 of FIGS. 18A and 18B. FIG. 19A is a front cross-sectional view of the device 10, and FIG. 19B is a side cross-sectional view of the device 10. The cap 20 includes a proximal extension 24, and the housing 14 may include a finger flange 15. As mentioned above, the finger flange 15 includes a rear cap 190, which may include a hook portion 182 that may hook onto a recessed portion 180 of the plunger rod 26. With reference to FIG. 19A, the housing 14 may also include a shoulder 28. Further details of the housing 14 and rear cap 190 are described below.

[0038] 20A-20C show views of the device 10 in a pre-injection state. FIG. 20A shows a quarter cross-sectional view of the device 10, FIG. 20B shows a detailed view of the proximal end of the housing 14 and rear cap 190 from FIG. 20A, and FIG. 20C shows a detailed view of the thumb pad 20 from FIG. 20A. Referring to FIG. 20B, the rear cap 190 and the housing 14 may include attachment means for attaching the rear cap 190 to the housing 14. For example, the rear cap 190 may include a snap 201 and the housing 14 may include an insert (not shown) allowing the rear cap 190 and the housing 14 to snap-fit ​​together. The rear cap 190 may include a tab 203 and the housing 14 may include a housing hook 205. When the rear cap 190 and housing 14 are attached (FIG. 20B), the tab 203 may seat within a portion of the housing 14 and the housing hook 205 may hook onto or seat on a portion of the tab 203. This configuration may serve as an anti-retraction feature to prevent the user from inadvertently pulling the plunger rod 14 out of the rear of the device 10. This configuration may also function as a pre-ejection prevention to prevent loss of drug product before the needle is inserted into the skin. As shown in FIG. 20C, the thumb pad 20 may include a flexible tab 22 and a proximal extension 24. FIG. 20C shows a quarter cross-sectional view of the thumb pad 20 of FIG. 20A. The thumb pad 20 may include multiple flexible tabs 22 and multiple proximal extensions 24. Referring to FIG. 20C, a portion of the flange 26 of the plunger rod 14 abuts a distal surface of the recess 27 of the flexible tab 22. Additionally, a portion of flange 26 may also seat on a proximal surface of ledge 29 of distal extension 24. Figures 21A-21C show device 10 of Figures 18A-20C after an injection, i.e., as it transitions to an end-of-dose state. At the start of an injection, the needle (not shown) of syringe 12 extends distally from housing 14. For example, about 6 mm of the needle may be exposed at the start of an injection.While the user pushes the thumb pad 20 distally toward the housing 14, the plunger rod 16 may also extend distally into the syringe 12, allowing the recess 180 to disengage from the hook portion 192. Referring to FIG. 21B, when the thumb pad 20 abuts the rear cap 190, the flexible tab 22 may flex outwardly away from the flange 26, allowing the flexible tab 22 to separate from the flange 26. When the thumb pad 20 abuts the rear cap 190, the distal extension 24 may abut the shoulder 28, pushing the shoulder 28 outwardly away from the syringe 12. The syringe 12 and plunger rod 16 may then move proximally such that the flange 26 of the plunger rod 16 may abut the distal surface of the thumb pad 20 (FIG. 21C). The needle 70 of the syringe 12 may then be sheathed within the housing 14 (FIG. 21A). This passive end-of-dose lockout mechanism may be actuated by an actuator, such as a spring 13, which may be located around the proximal end of the syringe 12 (FIG. 1B).

[0039] The embodiments of device 10 shown in FIGS. 18A-21C may include one or more additional features, such as a feature for locking thumb pad 20 in place with plunger rod 16 in a post-injection state and an alignment feature between thumb pad 20 and plunger rod 16 to reduce misalignment at the end of an injection. features); an ergonomic design to allow for two-handed operation, i.e., a first hand may hold the syringe for needle insertion at 90 degrees while a second hand presses the plunger rod 16; optimal configuration and sizing of the flexible tab 22, distal extension 24, plunger rod 16, and / or rear cap 190; an indicator of injection completion, e.g., a visual color change or an audible indicator; multiple activation points, e.g., pre-activation points or states, to mitigate potential failure modes; optimal configuration and sizing of the thumb pad 20 to fit the user's hand; an extension of the plunger rod 16 to seat within the piston of the device for improved alignment; and design optimization to reduce the spring force required to minimize plastic creep.

[0040] 3A-5D show another embodiment of the present disclosure in which the needle is covered in a pre-injection state. With reference to FIGS. 3A-3B, the device 50 can be designed to hold any conventional product container 52, e.g., a syringe. The device 50 can include a housing 54, a plunger rod 56, a stopper 60, a blocking component 62, and a needle cover 64. As shown, for example, in FIG. 3B, the plunger rod 56 can include a first recess 58 at a distal region and a second recess 59 at a proximal region. The blocking component 62 can be located at a proximal end of the housing 54. The plunger rod 56 can be slidably coupled to the blocking component 62 such that the plunger rod 56 can slide distally through the blocking component 62. The needle cover 64 can include a proximal end 66 that abuts a flexible arm 63 of the blocking component 62. As shown in FIGS. 3A-3B, the blocking component 62 may include two or more flexible arms 63. For example, the blocking component 62 may include two, three, four, or more flexible arms 63. In configurations with two or more flexible arms, the flexible arms may be equally spaced apart from one another. For example, if the blocking component 62 includes four flexible arms 63, each of the flexible arms may be approximately 90 degrees apart from one another. For example, the blocking component 62 may have a pair of flexible arms 63 that are, for example, approximately 180 degrees apart from one another. Thus, the description herein may be applicable to devices having a variety of numbers of components. In some examples, the needle cover 64 may include a slot 55 (FIGS. 3A-4D) configured to receive a portion of the housing 54. The slot 55 is described further below.

[0041] Figure 3A shows the device 50 prior to use, where the needle cover 64 may be fully extended distally of the housing 54, covering the needle 70 in an initial starting position. Figure 3B shows the device 50 in use, where the needle cover 64 has been depressed and can be moved proximally into the housing 54, for example, by pressing the device 50 against an injection site. The detailed configuration and interaction of the needle cover 64 and blocking component 62 will be further described when use of the device 50 is described.

[0042] In an initial position before use, as shown in FIGS. 4A-4B, the distal end of the flexible arm 63 may fit inside a portion of the first recess 58 of the plunger rod 56. For example, the distal portion of the flexible arm 63 may abut against the inside of a portion of the first recess 58 at contact point A. The distal end 66 of the needle cover 64 may also abut against a portion of the flexible arm 63 at contact point B. In this initial position, significant movement of the plunger rod 56 in either the proximal or distal direction may be prevented before use. For example, as shown in FIGS. 4A-4B, when the plunger rod 56 is pushed distally into the housing 54, the flexible arm 63 is prevented from deflecting outward by the proximal end 66 of the needle cover 64, locking the flexible arm 63 inside the first recess 58 and preventing further movement of the plunger rod 56. As shown in Figures 4C-4D, when the plunger rod 56 is pulled in the proximal direction away from the housing 54, the flexible arm 63 is again prevented from bending outward by the proximal end 66 of the needle cover 64, locking the flexible arm 63 within the first recess 58 and preventing further movement of the plunger rod 56.

[0043] To initiate an injection, the device 50 can be pressed against the injection site to depress the needle cover 64. As the needle cover 64 is moved distally, the proximal end 66 of the needle cover 64 moves proximally out of engagement with the flexible arm 63. This can allow the plunger rod 56 to be pushed distally toward the housing 54 for injection. In other words, as the needle cover 64 moves proximally within the housing 54 and the proximal end 66 moves away from contact point B, the plunger rod 56 can deflect the arm 63 of the blocking component 62, allowing the first recess 58 to move past the flexible arm 63 (FIG. 5A) so that the injection can proceed. As shown in FIG. 5A, the proximal end 66 of the needle cover 64 can move proximally within the housing and abut a portion of the blocking component 62.

[0044] Once the injection is complete, the device 50 may be removed from the injection site and the needle cover 64 may be pulled downward in a distal direction (FIGS. 5B-5C). In some examples, the device 50 may include a spring shroud 53 (FIGS. 3A and 5A-5D) for pulling the needle cover 64 and biasing it in a proximal direction. As shown in FIGS. 5B-5C, the plunger rod 56 is fully pushed into the housing 54. As shown in FIGS. 4A and 4C, the portion of the plunger rod 56 in the second recess 59 is smaller in diameter compared to the portion of the plunger rod 56 in the first recess 58, creating a larger second recess 59 compared to the first recess 58. Thus, when the plunger rod 56 is fully pushed into the housing 54 at the end of the injection, the area between the plunger rod 56 and the flexible arm 63 at the second recess 59 increases (FIG. 5B). This space can allow the distal end 66 of the needle cover 64 to deflect the flexible arm 63 inward toward the plunger rod 56, so that the proximal end 66 can move distally past the flexible arm 63 (FIG. 5C). In some embodiments, there can be a spring shroud 53 around the needle cover 64, and the needle cover 64 can move past the flexible arm 63 using a spring force. Referring to FIG. 5D, once the proximal end 66 has cleared the flexible arm 63, the flexible arm 63 can return to an undeflected position, and the proximal end 66 can be stopped by the flexible arm 63 from moving proximally again. Since the needle cover 64 can no longer move proximally to expose the needle 70, the flexible arm 63 can now act as a lockout mechanism to prevent reuse of the device 50 or accidental needle sticks. In this final, post-injection position of device 50, needle cover 64 may be in a locked out position and proximal end 66 and flexible arm 63 may abut at contact point C (FIG. 5D). Needle cover 64 and proximal end 66 are prevented from further movement with proximal end 66 held between ledge 72 of housing 54 and flexible arm 63. In addition, device 50 will not be reused.

[0045] In some embodiments, the slot 55 of the needle cover 64 may be configured to slidably receive the ledge 72. For example, as the needle cover 64 moves, the ledge 72 can move within the slot 55. The ledge 72 can move distally and / or proximally within the slot 55. As described above, in a post-injection position of the device 50, the proximal end 66 is held between the ledge 72 of the housing 54 and the flexible arm 63, and the ledge 72 can be within the slot 55. As shown in FIG. 3A, the needle cover 64 can include a complementary number of slots aligned with the ledges 72 of the housing 54. In some embodiments, the housing 54 can include a single ledge and the needle cover 64 can include a single slot aligned with the ledge. In some embodiments, the housing 54 can include two ledges and the needle cover 64 can include two slots, one aligned with each ledge. The slot 55 can extend through the needle cover 64. In other embodiments, the slot 55 may be a recess or groove that does not extend completely through the needle cover 64 .

[0046] The embodiment of Figures 3A-5D illustrates a device with a passive safety mechanism that is activated when the user is nearing the end of a dose, i.e., when a significant amount of product has been completely expelled from the container 52. The passive safety mechanism of Figures 3A-5D prevents accidental needle sticks after an injection because the needle cover 64 cannot be depressed until the device 50 is pressed against the injection site, and when the device 50 is removed from the injection site, the needle cover 64 springs back to extend from the distal end of the housing 54 to cover the needle 70.

[0047] In addition, the passive safety mechanism of Figures 3A-5D can prevent premature lockout. For example, some conventional drug delivery devices may automatically lock out when the device is removed from the injection site, even if the product is not fully expelled. With reference to Figures 5C-5D, only when the plunger rod 56 is fully depressed into the housing 54 can the proximal end 66 of the needle cover 64 deflect the flexible arm 63 into the second recess 59, such that the proximal end 66 can move distally beyond the flexible arm 63 to a position adjacent the ledge 72 and abut the flexible arm 63 at contact point C. The plunger rod 56 is only fully depressed at the end of administration, and thus lockout does not occur before the entire dose of product in the container 52 is expelled. If the device 50 is removed from the injection site during injection, i.e., before the plunger rod 56 is fully depressed into the housing 54, the needle cover 64 is not locked out and the device 50 can be returned to the injection site to continue the injection.

[0048] In addition, because the needle 70 is within the needle cover 64 before and after injection, the user cannot see the needle 70 at any time before, during, and / or after the injection. Thus, the needle cover 64 can reduce needle phobia and needle-related anxiety compared to conventional drug delivery devices with exposed needles. In addition, exposing only a portion of the needle 70 can allow the use of the device 50 without any pre-injection steps, such as pinching the skin to change the injection depth, to compensate for the longer needle length compared to the exposed needle 70 of the device 50 (FIG. 3B). The device 50 can be configured, e.g., the container 52 can be positioned within the housing 54 and / or the size of the needle cover 64 can be set, such that the retracted position of the needle cover 64 exposes only a portion of the needle 70, and the length of the exposed portion of the needle 70 indicates the desired insertion depth of the needle 70.

[0049] In some embodiments, the device 50 may include a feedback mechanism. The device 50 may include a visual feedback mechanism, for example, the plunger rod 56 fully depressed into the housing 54 (FIG. 5B) and the needle cover 64 fully extended proximally of the housing 54 with the needle 70 covered. In some examples, the device 50 may include an opening for viewing the container 52 and the movement of the plunger rod 56 and stopper 60 within the container 52. The device 50 may also include an audible feedback mechanism, for example, an audible "click" sound, when the proximal end of the plunger rod 56 and the housing 54 connect. In some aspects, the device 50 may include a tactile feedback, for example, a snap or vibration, when the needle cover 64 moves proximally and abuts the ledge 72 as the injection is completed.

[0050] 6A-6B, a device 80 may be configured to hold any conventional product container 92, such as a syringe. The device 80 may include a housing 74, a plunger rod 76, a stopper 90, a blocking component 82, and a needle cover 84. As shown, for example, in FIG. 6B, the plunger rod 76 may include a first recess 78 at a distal region and a second recess 79 at a proximal region. The blocking component 82 may be located at a proximal end of the housing 74. The plunger rod 76 may be slidably coupled to the blocking component 82 such that the plunger rod 76 may slide through the blocking component 82. As shown in FIGS. 6A-6B, the blocking component 82 may include two or more flexible arms 83. For example, the blocking component 82 may include two, three, four, or more flexible arms 83. In configurations having two or more flexible arms, the flexible arms may be equally spaced apart from one another. For example, if the blocking component 82 includes four flexible arms 63, each of the flexible arms may be approximately 90 degrees apart from one another. For example, the blocking component 82 may have a pair of flexible arms 83 that are, for example, approximately 180 degrees apart from one another. Thus, the description herein may be applicable to devices having a variety of numbers of components.

[0051] FIG 6A shows the device 80 prior to use, with the needle 96 extending distally from the housing 74 and needle cover 84. An optional removable needle shield 94 may be inserted into or over the needle cover 84 and / or housing 74 to cover the needle 96. FIG 6B shows the device 80 prior to use after the needle shield 94 has been removed. In contrast to the embodiment of FIGS. 3A-3B, the needle 96 extends beyond the needle cover 84 in the initial state of the device, so that the needle cover 84 does not need to be depressed prior to use. Once the needle shield 94 is removed, the needle 96 becomes visible to the user prior to injection.

[0052] As shown in FIGS. 7A-7B, in an initial position prior to use, the distal end of the flexible arm 83 may fit into at least a portion of the first recess 78 of the plunger rod 76. For example, the distal portion of the flexible arm 83 may abut a portion of the first recess 78 at contact point E. The proximal end 86 of the needle cover 84 may also abut a portion of the flexible arm 83 at contact point D. In this initial position, prior to use, significant movement of the plunger rod 76 in either the proximal or distal direction may be prevented. For example, when the plunger rod 76 is pushed distally into the housing 74 using normal injection forces, the contact between the flexible arm 83 and the plunger rod 76 at contact point E, as well as the contact between the proximal end 86 of the needle cover 84, may prevent proximal movement of the plunger rod 76. The configuration of flexible arm 83, plunger rod 76 with first recess 78, and proximal end 86 of needle cover 84 may prevent movement of plunger rod 76 in a distal direction unless an increased amount of force is applied, i.e., a force higher than a typical injection force. If plunger rod 76 is pulled proximally away from housing 74, flexible arm 83 may contact an edge of first recess 78 and prevent movement of plunger rod 76 in a distal direction.

[0053] To initiate an injection, the device 80 is pressed against the injection site, allowing the needle 96 to puncture the injection site. The plunger rod 76 can then be pushed distally toward the housing 74 using a force higher than a normal injection force. As the plunger rod 76 is pressed down into the housing 74, the flexible arms 83 will deflect radially outwardly away from the plunger rod 76 and contact point E when subjected to a higher than normal release force, allowing the first recess 78 to move past the flexible arms 83 (FIG. 7C). The higher than normal release force may be, for example, a force greater than about 2 Newtons (N), for example, about 3 N to about 20 N.

[0054] Once the injection is complete, the device 80 is removed from the injection site and the plunger rod 76 is pushed fully down into the housing 74 so that the plunger rod 76 may abut against the housing 74, as shown in FIG. 7D. When the device 80 is removed from the injection site, the needle cover 84 may include a spring shroud 73 (FIG. 6A) for moving the needle cover 84 downward in a distal direction. As shown in FIGS. 6A-6B, the portion of the plunger rod 76 in the second recess 79 is smaller in diameter compared to the portion of the plunger rod 76 in the first recess 78, creating a larger second recess 79 compared to the first recess 78. Thus, when the plunger rod 76 is pushed fully down into the housing 74 at the end of the injection, there is an increased area between the plunger rod 76 and the flexible arm 83 in the second recess 79 (FIG. 7D). This space can allow the proximal end 86 of the needle cover 84 to deflect the flexible arm 83 inward toward the plunger rod 76, so that the proximal end 86 can move distally past the flexible arm 83 (FIG. 7E). In some embodiments, there can be a spring shroud (not shown) around or at the end of the needle cover 84, and the needle cover 84 can move past the flexible arm 83 using a spring force. Referring to FIG. 7E, once the distal end 86 passes the flexible arm 83, it can deflect the flexible arm 83 back to its initial position, and the needle cover 84 can be stopped by the flexible arm 83 from moving proximally again. The flexible arm 83 can now act as a lockout mechanism to prevent reuse of the device 80 or accidental needle sticks, since the needle cover 84 can extend further distally compared to the starting position where the needle cover 84 covers the needle 96. In this final, post-injection position of device 80, needle cover 84 may be extended distally in a locked out position, where needle cover 84 may abut ledge 98 at contact point F to prevent further movement of needle cover 84 in the proximal direction. Proximal end 86 of needle cover 84 may also abut the distal end of flexible arm 83, such that further proximal movement of needle cover 84 and proximal end 86 may be prevented.

[0055] In some examples, the needle cover 84 may include a slot 75 (FIG. 6A) configured to receive a portion of the housing 74. In some embodiments, the slot 75 of the needle cover 84 may be configured to slidably receive a ledge 98. For example, as the needle cover 84 moves, the ledge 98 may move within the slot 75. The ledge 98 may move distally and / or proximally within the slot 75. As described above, in a post-injection position of the device 80, the proximal end 86 is held between the ledge 98 of the housing 74 and the flexible arm 83, and the ledge 98 may be within the slot 75. As shown in FIG. 6A, the needle cover 84 may include a complementary number of slots aligned with the ledges 98 of the housing 74. In some embodiments, the housing 74 may include a single ledge and the needle cover 84 may include a single slot aligned with the ledge. In some embodiments, the housing 74 may include two ledges and the needle cover 84 may include two slots, one aligned with each ledge, etc. The slot 75 may extend through the needle cover 84. In other embodiments, the slot 75 may be a recess or groove that does not extend completely through the needle cover 84.

[0056] The embodiment of Figures 6A-7F shows a device with a passive safety mechanism that can be activated when the user is nearing the end of administration, i.e., when a significant amount of product has been completely expelled from the container 92. The passive safety mechanism of Figures 6A-7F can also prevent premature lockout. For example, some conventional drug delivery devices can automatically lock out when the device is removed from the injection site, even if the product has not been completely expelled. With reference to Figures 7D-7F, only when the plunger rod 76 is fully depressed into the housing 74 can the proximal end 86 of the needle cover 84 deflect the flexible arm 83 into the second recess 79, such that the needle cover 84 can move distally beyond the flexible arm 83 and then abut the ledge 98 at contact point F. When the plunger rod 76 is fully depressed, the entire dose of product in the container 92 can be expelled. If the device 80 is removed from the injection site during injection, i.e., before the plunger rod 76 is fully pushed into the housing 74, the needle cover 84 is not locked out and the device 80 can be replaced at the injection site to continue the injection.

[0057] Furthermore, because a portion of the needle 96 is within the needle cover 84, the user can only see a portion of the needle 96 at any time before and / or during the injection. The needle cover 84 can extend from the proximal end of the housing 74 to cover the needle 96 after the injection, so that the user cannot see any portion of the needle 96 when the administration is completed. Thus, the needle cover 84 can reduce needle phobia and needle-related anxiety compared to conventional drug delivery devices with exposed needles. In addition, by exposing only a portion of the needle 96, the device 80 can be used without any pre-injection steps, such as pinching the skin to change the injection depth, to compensate for the longer needle length compared to the exposed needle 96 of the device 80 (FIG. 6B). The device 80 can be configured, for example, the container 92 can be positioned within the housing 74 and / or the size of the needle cover 84 can be set, such that the needle cover 84 exposes only a portion of the needle 96, and the length of the exposed portion of the needle 96 indicates the desired insertion depth of the needle 96.

[0058] 7C, the safety mechanism may also prevent pre-excretion of the product. As discussed above, the force applied to the plunger rod 76 by the flexible arm 83 and the proximal end 86 of the needle cover 84 prevents movement of the plunger rod 76 until an initial "break" force, i.e., a force greater than a normal injection force, occurs to overcome the force between the flexible arm 83, the proximal end 86 and the plunger rod 76. This "break" force may be adjusted as desired for a particular drug product, and may be high enough to prevent the drug product from being expelled too quickly, but low enough so that the user does not have difficulty initiating the injection.

[0059] In some embodiments, the device 80 may include a feedback mechanism. The device 80 may include a visual feedback mechanism, for example, the plunger rod 76 fully depressed into the housing 74 (FIG. 7B) and the needle cover 84 fully extended distally into the housing 74 with the needle 96 covered. In some examples, the device 80 may include an opening for viewing the receptacle 92 and the movement of the plunger rod 76 and stopper 90 within the receptacle 92. The device 80 may also include an audible feedback mechanism, for example, an audible "click" sound, when the proximal end of the plunger rod 76 abuts the housing 74 or when the needle cover 84 is pushed distally from the housing 74. In some aspects, the device 80 may include a tactile feedback, for example, a snap or vibration, when the needle cover 84 moves distally and abuts the ledge 98 as the injection is completed.

[0060] 14A-14C show another embodiment of the present disclosure that is similar to that described above with reference to FIGS. 3A-7F. Where appropriate, features are designated with similar reference numerals as described above. Any features and components that correspond to features and components of FIGS. 3A-7F may be understood to be similarly configured. FIG. 14A shows an exterior perspective view of device 140, FIG. 14B shows an exterior front view of device 140, and FIG. 14C shows an exterior side view of device 140. Device 140 may include plunger rod 56, housing 54, and needle cap 148. Housing 54 may include finger flange 142 and rear cap 144. Finger flange 142 may have any suitable size and / or configuration that allows for appropriate use. For example, a user may utilize two hands to operate device 140. Device 140 may be held in one hand of the user and plunger rod 56 may be pushed distally toward finger flange 142 with the user's other hand. 14A-14C, rear cap 144 may include a collar 146. Collar 146 may extend proximally away from finger flange 142. Collar 146 may be of any suitable size and / or configuration to surround a portion of plunger rod 56. In some embodiments, collar 146 may have a generally circular shape.

[0061] 15A-15D show cross-sectional views of the interior of device 140. FIGS. 15A and 15B show cross-sectional views of a quarter portion of device 140. With reference to FIG. 15A, device 140 may include needle cover 64, syringe 52, spring shroud 53, needle cap 232, and needle shield 94. The configuration of needle cap 232 and needle shield 94 is described in detail herein, for example, with respect to FIGS. 22A and 22B. With reference to FIG. 15B, device 50 may include various features for coupling finger flange 142 and rear cap 144 together. For example, finger flange 142 may include snap 155, and rear cap 144 may include insert 156. Snap 155 and insert 156 may be engaged, i.e., snap-fit ​​together, to couple rear cap 144 to finger flange 142. The rear cap 144 may also include a rear cap hook 157 for abutting a ledge portion 158 of the housing 14 .

[0062] 15B-15D, the device 50 is shown in a pre-injection state. The rear cap 144 may include a blocking component 160. The blocking component 160 may correspond to the blocking component 62 described above. The plunger rod 56 may include a recess 170 and be slidably coupled to the blocking component 62 such that the plunger rod 56 may slide in both distal and proximal directions. The blocking component 62 may include a flexible arm 63 extending in a distal direction. As shown in FIG. 15B, the blocking component 62 may include two or more flexible arms 63. For example, the blocking component 62 may include two, three, four, or more flexible arms 63. In configurations having two or more flexible arms 63, the flexible arms 63 may be equally spaced apart from one another. For example, if the blocking component 62 includes four flexible arms 63, each of the flexible arms 63 may be approximately 90 degrees from one another.

[0063] In the pre-injection state, one or more of the flexible arms 63 can abut a portion of the plunger rod 56. For example, one or more of the flexible arms 63 can abut a recess 170 of the plunger rod 56 (FIG. 15B). The needle cover 64 can include an opening 172 for receiving a portion of one or more of the flexible arms 63. In the pre-injection state, the first flexible arm 63a can abut the plunger rod 56 such that a portion of the first flexible arm 63a can fit within the opening 172 (FIG. 15C). The second flexible arm 63 can abut the recess 170 (FIG. 15D). In this initial position, significant movement of the plunger rod 56 in either the proximal or distal direction can be prevented prior to use. For example, if the plunger rod 56 is pushed distally into the housing 54, the first flexible arm 63a is prevented from deflecting outward by the distal end of the needle cover 64, locking the flexible arm 63 within the opening 172 and preventing further movement of the plunger rod 56. If the plunger rod 56 is pulled proximally away from the housing 54, the second flexible arm 63b may be prevented from deflecting outward as the second flexible arm 63b abuts the recess 170.

[0064] To begin an injection, the device 140 can be pressed against the injection site to depress the needle cover 64. As the plunger rod 56 is pushed distally into the housing 54, it can deflect the second flexible arm 63b of the blocking component 62, allowing the plunger rod 56 to move distally within the syringe 52 so that the injection can proceed. Once the injection is complete, the device 140 can be removed from the injection site, or the needle cover 64 can be automatically pulled distally to cover the needle 70 (FIG. 16B). In some examples, the spring shroud 53 can pull the needle cover 64 distally. During an injection, as the plunger rod 56 moves distally within the housing 54, the first flexible arm 63a deflects inwardly toward the plunger rod 56, allowing the first flexible arm 63a to separate from the opening 172. 16A, at the end of an injection, when the first flexible arm 63a is positioned proximally relative to the needle cover 64, the first flexible arm 63a can return to an undeflected position and the needle cover 64 can be prevented from moving in a proximal direction. Since the needle cover 64 cannot move distally to expose the needle 70, the first flexible arm 63a can act as a lockout mechanism to prevent reuse of the device 140 or accidental needle sticks. In this final post-injection position of the device 140, the needle cover 64 can be in a locked out position and the proximal end of the needle cover 64 and the first flexible arm 63a can abut one another. At this stage, the device 140 does not have to be reused.

[0065] 14A-16B may include one or more additional features, such as optimal configuration and sizing of flexible arm 62; ergonomic design to allow for two-handed operation, i.e., a first hand may hold the syringe for needle insertion at 90 degrees while a second hand presses down on plunger rod 56; an indicator of injection completion, such as a visual color change or an audible indicator; multiple activation points, such as pre-activation points or states, to mitigate potential failure modes; an extension of plunger rod 56 to seat within the piston of the device to improve alignment of plunger rod 56 before and / or during use; and design optimization to reduce the spring force required to minimize plastic creep.

[0066] Another embodiment of the present disclosure is shown in Figures 8A-10B. Figure 8A shows an exterior view of device 100, and Figure 8B shows a cross-sectional view of the device. Device 100 may be configured to hold any suitable commercially known product container 104 (e.g., a syringe or other suitable drug delivery device). With reference to Figure 8B, device 100 may include a housing 106, a needle cover 108, a plunger rod 110, a stopper 112, and a rotating component 114, e.g., a cam.

[0067] Prior to injection, the needle cover 108 may extend distally from the housing 106 to cover the needle 118. To initiate an injection, the device 100 may be pressed against the injection site. The device 100 may include a spring (not shown), for example, around or at the end of the needle cover 108. An exemplary actuator, for example, a spring 124, is shown diagrammatically in FIGS. 9A-9D for illustrative purposes. The upper region of each of FIGS. 9A-9D shows a cross-section of the plunger rod 110, the rotating component 114, and the protrusion 116 of the needle cover 108 interacting with the track 120 of the rotating component 114. The lower region of each of FIGS. 9A-9D shows a side view of the movement of the protrusion 116 of the needle cover 108 along the track 120 of the rotating component 114 corresponding to the cross-sectional view of that figure.

[0068] As shown in FIGS. 9A-9D, the rotating component 114 may include a track 120, or groove, for receiving the protrusion 116 of the needle cover 108. In an initial position (FIG. 9A), the actuator 124 may be uncompressed, the needle cover 108 may extend distally over the needle 118, and the plunger rod 110 may be locked in place relative to the rotating component 114. This may prevent the plunger rod 110 from being pushed distally into the housing 106 until the needle cover 108 has been pushed proximally to expose the needle 118. To initiate an injection, the plunger rod 110 may be twisted relative to the rotating component 114, allowing the plunger rod 110 to move from a locked position to an unlocked position. The needle cover 108 may be pushed proximally into the housing 106, for example, by the user pressing the device 100 against an injection site, which may rotate the rotating component 114 and compress the actuator 124 during injection (FIG. 9B). The plunger rod 110 may be locked in place, i.e., prevented from moving, until the needle cover 108 is retracted proximally into the housing 106. Such a configuration may prevent premature expulsion of product. During injection, the needle cover 108 may be held in a retracted position due to the location of the protrusion 116 on the needle cover 108 in the track 120 of the rotating component 114 (FIG. 9B). This may act as a signal to the user that the device 100 is still in use. In this retracted position, the needle cover 108 may also control the insertion depth of the needle 118, as the distal end of the needle cover 108 prevents deeper insertion of the needle 118 when the distal end of the needle cover 108 contacts the injection site. Once the injection is complete, the plunger rod 110 may pivot the rotating component 114, releasing the needle cover 108 (FIG. 9C), and the actuator 124 may push the needle cover 108 back to the locked out position, where the needle cover 108 extends distally from the housing 106 (FIG. 9D), covering the needle 118, once the injection is complete.As can be seen in FIG. 9D, in the locked out position, when the injection is completed, the protrusion 116 on the needle cover 108 can engage a notch at the end of the track 120 on the rotating component 114, thereby preventing the needle cover 108 from being pushed proximally again into the housing 106, thereby preventing reuse of the device 100.

[0069] In some embodiments, in the locked out position, the needle cover 108 may be pushed further distally than the initial position of the needle cover 108. For example, FIG. 10A shows the initial position of the needle cover 108 before injection, and FIG. 10B shows the locked out position of the needle cover 108 at the end of administration. Portion 122 shows an additional portion of the needle cover 108 that is exposed at the end of injection, but not at the beginning of injection. In some embodiments, the height of the track 120 that rotates the component 114 is higher at the end compared to the beginning of the track 120. For example, the beginning of the track 120 (shown to the left of the rotating component 114 in FIGS. 9A-9D) may start from a central region of the rotating component 114, continue to an upper region of the rotating component 114, and then the end of the track 120 (shown to the right of the rotating component 114 in FIGS. 9A-9D) may be located at a lower region of the rotating component 114. Thus, the height of the end of the track 120 is higher than the height of the beginning portion of the track 120. This increased height at the end of the track 120 may allow the needle cover 108 to extend further in its locked out position than in its original position (FIG. 10B).

[0070] The embodiment of Figures 8A-10B shows a device with a passive safety mechanism that can be activated when the user is nearing the end of administration, i.e., when a sufficient amount of product has been completely expelled from the container 104. The passive safety mechanism of Figures 8A-10B can push the needle cover 108 proximally to an extended lockout position to allow the plunger rod 110 to rotate the rotating component 114 when the end of administration is near. In that locked out position, the needle cover 108 cannot retract back into the housing 106. In such a locked out position, prior to injection, the needle cover 108 can cover the needle 118 to prevent accidental needle sticks after injection. This can also reduce needle phobia and needle-related anxiety compared to conventional drug delivery devices with exposed needles. In addition, the needle cover 108 can allow for a controlled needle insertion depth. In other words, exposing only a portion of the needle 118 during injection may allow the device 100 to be used without any pre-injection steps, such as pinching the skin to alter the injection depth, to compensate for the longer needle length compared to the exposed needle 118 of the device 100. The device 100 may be configured, e.g., the container 104 may be positioned within the housing 106 and / or the needle cover 108 may be sized such that the needle cover 108 exposes only a portion of the needle 118, and the length of the exposed portion of the needle 118 indicates the desired insertion depth of the needle 118. As described above, during injection, the needle cover 108 may be held in the retracted position (FIG. 9B) due to the position of the protrusion 116 on the needle cover 108 within the track 120 of the rotating component 114. This may prevent the passive safety mechanism from being activated before the end of the administration. Furthermore, if the device 100 is accidentally or intentionally removed from the injection site, the passive safety mechanism is not activated because the needle cover 108 is retained within the track 120. When the device 100 is reapplied to the injection site and the plunger rod 110 is depressed, the injection can be resumed.

[0071] In some embodiments, the device 100 may include a feedback mechanism. The device 100 may include a visual feedback mechanism, for example, the plunger rod 110 abutting the housing 106, the needle cover 108 extending fully distally from the housing 106, and / or the distal extension portion 122 of the housing 106 (FIG. 10B). In some examples, the needle cover 108 may have, for example, a first color, pattern, or texture, and the extension portion 122 may have a second color, pattern, or texture to indicate that the device 100 is in a locked out position, the device has been used, and a dose has been expelled. In some examples, the device 100 may include an opening 102 for viewing the container 104 and the movement of the plunger rod 110 and / or stopper 112 within the container 104. The device 100 may also include an audible feedback mechanism, e.g., an audible "click" sound, when the plunger rod 110 abuts the housing 106 and / or the needle cover 108 moves distally at the end of administration. In some embodiments, the device 100 may include tactile feedback, e.g., a snap or vibration, when the needle cover 108 moves distally at the end of an injection.

[0072] Device 100 may be of any suitable size and shape for holding or partially holding container 104 and / or for supporting and holding any of the components described herein. Any of the components of device 100 may be of a suitable size and / or shape for configuring relative to and cooperating with other components as designed. For example, rotating component 114 may be of any suitable size and / or shape for slidably coupling to plunger rod 110. In another example, needle cover 108 and / or protrusion 116 may be of any suitable size and / or shape to fit within track 120 of rotating component 114.

[0073] Another embodiment of the present disclosure is shown in Figures 11-13B. Figure 11 shows an exterior view of a device 200. The device 200 can be designed to hold any suitable commercial product container 202 (e.g., a syringe or other suitable drug delivery device). With reference to Figure 11, the device 200 can include a housing 204, a plunger rod 206, a needle cover 208, and a stopper 230. A proximal region of the housing 204 can include one or more flexible housing tabs 212. The housing 204 can also include a cap 210 located within a proximal portion of the housing 204. The device 200 can include a lockout ring 214 slidably coupled to a proximal end of the container 202. In some embodiments, the housing 204 can include two or more flexible housing tabs 212. For example, the housing 204 can include two, three, four, or more flexible housing tabs 212. In configurations having two or more flexible housing tabs 212, the flexible housing tabs 212 may be equally spaced from one another. For example, if the housing 204 includes four flexible housing tabs 212, each of the flexible housing tabs 212 may be approximately 90 degrees from one another. If the housing 204 includes two flexible housing tabs 212, each of the flexible housing tabs 212 may be approximately 180 degrees from one another.

[0074] As shown in FIG. 11, the needle cover 208 may be extended and cover the needle 220 prior to use. In an initial position (FIG. 12A), the flexible housing tab 212 may abut a portion of the lockout ring 214, which may be located proximate to the proximal end 216 of the needle cover 208. The needle cover may be biased distally, for example, by a spring, and pushed back proximally within the housing 204 for use. To initiate an injection, the needle cover 208 is pushed proximally into the housing 204, for example, by pushing the device 200 against an injection site. As the needle cover 208 is moved proximally, the proximal end 216 of the needle cover 208 may hook onto a ledge 224 of the lockout ring 214 (FIG. 12B). The movement of the proximal end 216 of the needle cover 208 relative to the lockout ring 214 is shown in further detail in FIGS. 13A-B. In some examples, the proximal end 216 may include a notch 222 for engaging with the ledge 224. In some embodiments, the needle cover 208 may include a plurality of notches 222, e.g., a pair of notches, and the lockout ring 214 may include a plurality of ledges 224, e.g., a pair of ledges. The number of ledges and notches may correspond to one another such that each ledge may engage with each notch. Although the lockout ring 214 is shown as including one or more ledges 224 and the proximal end 216 of the needle cover 208 is shown as including one or more notches 222, the two mating regions may be reversed, i.e., the lockout ring 214 may include one or more notches 222 and the needle cover 208 may include one or more ledges 224. Additionally, the ledges 224 and notches 222 may represent any suitable plurality of mating portions.

[0075] For example, when the needle cover 208 is pushed proximally into the housing 204 by pressing the device 200 against the injection site, the plunger rod 206 is pushed distally into the housing 204, allowing product to be expelled from the container 202 to the injection site.

[0076] Movement of the proximal end 216 of the needle cover 108 into the interior of the housing 204 can deflect the flexible tab 212 outwardly away from the plunger rod 206 during an injection, as shown by the arrows pointing radially outward in FIG. 12B. When the device 200 is removed from the injection site, e.g., when an injection is completed, the needle cover 208 along with the lockout ring 214 may be biased to retract downwardly to its initial position, e.g., using the spring force of a spring shroud (not shown) around the needle cover 208. The needle cover 208 and lockout ring 214, which are interconnected via the notch 222 and ledge 224, move downwardly over the flexible tab 212, allowing the flexible tab 212 to deflect back to its initial position (FIG. 12C). As shown in FIG. 12C, the proximal end of the lockout ring 214 can abut the distal end of the flexible tab 212. In this final, end-of-dose position, the needle cover 208 is in a locked-out position and the needle cover 208 may be prevented from returning proximally into the interior of the housing 204 by the flexible tab 212 blocking its path.

[0077] The embodiment of Figures 11-13B shows a device with a passive safety mechanism that can be activated at any time when the device 200 is removed from the injection site, whether or not the entire dose has been expelled from the container 202. The passive safety mechanism can be activated when the needle cover 208 is pushed proximally into the housing 204 to initiate the injection. Because the needle cover 208 is biased in a distal direction, the safety mechanism can be activated when the force pushing the needle cover 208 into the housing 204 is removed (e.g., by removing the device 200 from the user's skin). Such a passive safety mechanism can be useful for users concerned about needle safety. For example, if a user accidentally drops the device 200 during use, the passive safety mechanism can push the needle cover 208 out to prevent an accidental needle stick. Additionally, the needle 220 can be covered and hidden from view by the needle cover 208 before, during, and after injection. This can reduce needle phobia and needle-related anxiety compared to conventional drug delivery devices with exposed needles. In addition, the needle cover 108 may allow for a controlled needle insertion depth. In other words, exposing only a portion of the needle 220 during injection may allow the use of the device 200 without any pre-injection steps, such as pinching the skin to alter the injection depth, to compensate for the longer needle length compared to the exposed needle 220 of the device 200. The device 200 may be configured, e.g., the container 202 may be positioned within the housing 204 and / or the needle cover 208 may be sized, such that the needle cover 208 exposes only a portion of the needle 220, and the length of the exposed portion of the needle 220 indicates a desired insertion depth of the needle 220.

[0078] In some embodiments, the device 200 may include a feedback mechanism. The device 200 may include a visual feedback mechanism, e.g., the plunger rod 206 abutting the housing 204, the needle cover 208 fully extended distally from the housing 204. In some examples, the device 100 may include an opening for viewing the container 202 and the movement of the plunger rod 206 and / or the stopper 230 within the container 202. The device 200 may also include an audible feedback mechanism, e.g., an audible "click" sound, when the plunger rod 206 abuts the housing 204, when the needle cover 208 extends distally, and / or when the flexible tab 212 relaxes back to its initial neutral position (FIG. 12C). In some aspects, the device 200 may include a tactile feedback, e.g., a snap or vibration, when the needle cover 208 moves distally.

[0079] Device 200 may be of any suitable size and shape for holding or partially holding product container 202 and / or for supporting and holding any of the components described herein. Any of the components of device 200 may be of any suitable size and / or shape and may be configured to cooperate with other components as designed. For example, needle cover 208, proximal end 216, notch 222, lockout ring 214, and ledge 224 may be of any suitable size and / or shape that allows notch 222 to lock onto ledge 224.

[0080] 22A and 22B show an embodiment of a needle shield 94 and a needle cap 232 that may be used with any of the devices disclosed herein. The needle shield 94 may be attached to a needle cover (not shown) and may extend distally to completely surround the needle 96. As shown in FIGS. 22A and 22B, the needle shield 94 may extend distally such that the needle shield 94 may abut a portion of the needle cap 232. The needle cap 232 may include a clip 221. In other embodiments, the needle cap 232 may include multiple clips 221. The clip 221 may be shaped or configured to attach to or latch onto a ledge 223 of the needle shield 94. The needle cap 232 shown in FIGS. 22A and 22B shows the arms 95 of the needle shield 94. In other embodiments, the needle shield 94 may include multiple arms 95 and gaps between each arm 95. In some embodiments, the needle cap 232 may include at least two clips, at least three clips, or at least four clips. With reference to FIG. 22B, the first clip 221a may be attached to the first ledge 223a and abut the first arm 95 of the needle shield 94. The second clip 221b may be attached to the second ledge 223b. When the user pulls the needle cap 232 distally away from the housing 14, the needle shield 94 may simultaneously exit the housing 14, exposing the needle 86.

[0081] Additional concepts and features that may be used with or in any of the devices disclosed herein are described below. The following concepts and features may correspond to concepts and features described throughout this disclosure.

[0082] 23A and 23B show a plunger rod 235 that may be utilized in any of the embodiments described herein. The plunger rod 235 may include a first portion 236 and a second portion 237. As shown in FIG. 23A, the second portion 237 may have a width that is less than the width of the first portion 236. With reference to FIG. 23B, the second portion 237 may be folded, i.e., inserted, into the first portion 236 as the plunger rod 235 moves distally toward the housing 238 to dispense the medication from the syringe 12. In other embodiments, the first portion 236 may have a width that is less than the width of the second portion 237 such that the first portion 236 is folded into the second portion 237 as the plunger rod 235 moves distally toward the housing 238. The plunger rod 235 may be referred to as a telescoping plunger rod. As shown in Figures 23A and 23B, as plunger rod 235 collapses, the length of plunger rod 235 decreases from a first length (Figure 23A) to a second length (23B).

[0083] 24A-24C show an embodiment of the present disclosure. The device 240 may include a thumb pad 241, a plunger rod 242, a housing 243, a syringe 244, a spring shroud 245, a rotor 246, and a needle 249. In a pre-injection state, the rotor 246 may be located proximate to the proximal end of the syringe 244, as shown in FIG. 24A. Referring to FIG. 24C, the rotor 246 may include an opening 246a shaped and configured to surround a portion of the plunger rod 242. In some examples, the opening 246a may have a circular shape such that a portion of the plunger rod 242 may slide distally through the rotor 246. The rotor 246 may also include a plurality of notches 246b. The plurality of notches 246b may have a shape, size, and configuration corresponding to the proximal end of the syringe 244. For example, the plurality of notches 246b may correspond to the flange 247 of the syringe 244. In a pre-injection state, the rotor 246 may be located proximate the proximal end of the syringe 12 such that the notches 246b are spaced from the flange 247. The spring shroud 245 may surround the proximal end of the syringe 244 such that the syringe 244 is spring-loaded and held down by the rotor 246 (FIG. 24A). To initiate an injection, the user may depress the thumb pad 241 distally toward the housing 243. During an injection, as the plunger rod 242 moves distally into the housing 243 and the syringe 244, the plunger rod 242 may rotate such that the notches 246b rotate toward the flange 247. At the end of administration, as shown in FIG. 24B, the syringe 244 moves proximally into the housing 243 and into the rotor 246, and the needle 249 may be housed within the distal end of the housing 243. In some embodiments, the rotor 246 and the syringe 244 may not be coupled together and may then move proximally toward the proximal end of the housing 243. Any suitable syringe 244 may be used with the device 240.For example, syringe 244 may be a cyclo-olefin-polymer syringe or a glass cut flange syringe.

[0084] FIG. 25 illustrates one embodiment of the present disclosure. The device 250 may include a housing 251, a syringe 252, and a thumb pad 253. The device 250 may also include a telescoping plunger rod including a first portion 254 and a second portion 255. The telescoping plunger rod may correspond to the plunger rod 235 shown in FIGS. 23A and 23B. As shown in FIG. 25, the first portion 254 may include a plurality of ledges 254a, and the second portion 255 may include a plurality of notches 255a. The plurality of ledges 254a may fit within the notches 255a to couple the first portion 254 to the second portion 255. At the end of administration, the thumb pad 253 may abut against the flange portion 251b of the housing 251. The housing 251 may include a plurality of proximal extensions 251a. 25, when thumb pad 253 abuts flange portion 251b at the end of administration, first portion 254 and second portion 255 may also abut proximal extensions 251a. When first portion 254 and second portion 255 abut proximal extensions 251a, ledges 254a may push proximal extensions 251a, deflecting them outwardly and away from syringe 252. Spring shroud 258 may then retract syringe 252 and / or second portion 254 proximally into thumb pad 253 and retract a needle at the distal end of the syringe (not shown) into housing 251. In some embodiments, thumb pad 253 and housing 251 may include attachment features that lock thumb pad 253 and housing 251 together at the end of administration.

[0085] 26A and 26B show an embodiment of the present disclosure. The device 260 may include a housing 261, a syringe 262, and a plunger rod 263. The device 260 may also include an inner rod 264 extending through the plunger rod 263. As shown in FIG. 26A, the inner rod 264 may include a button 264a extending proximally from a thumb pad 263a of the plunger rod 263. In a pre-injection state, the multiple flexible arms 263b of the plunger rod 263 may abut against a distal portion of the inner rod 264, preventing the plunger rod 263 from moving, and thus preventing pre-ejection of the contents of the syringe 262. A spring 269 may be included in the plunger rod 263. To initiate an injection, a user may press the button 264a and push the thumb pad 263a distally toward the housing 261 against the spring 269. Depressing button 264a can move inner rod 264 distally toward housing 261. Referring to FIG 26B, as inner rod 264 moves distally into housing 261, flexible arms 263b are then deflected inwardly into recesses 264b. With flexible arms 263b deflected into recesses 264b, plunger rod 263 is free to move distally to administer the contents of syringe 262.

[0086] 27A and 27B show a device 270 that is similar to the device 260 of FIGS. 26A and 26B. The device 270 may include a housing 271, a syringe 272, and a plunger rod 273. The device 270 may also include an inner rod 274. As shown in FIG. 27A, the inner rod 274 may include a button 274a extending proximally from a thumb pad 273a of the plunger rod 273. In a pre-injection state, the multiple flexible arms 273b of the plunger rod 273 may abut against a distal portion of the inner rod 274, preventing the plunger rod 273 from moving, and thus preventing pre-ejection of the contents of the syringe 272. A spring 279 may be included in the plunger rod 273. To initiate an injection, a user may press the button 274a and push the thumb pad 273a distally toward the housing 271 against the spring 279. Depressing button 274a can move inner rod 274 distally toward housing 271. Referring to FIG 27B, as inner rod 274 moves distally into housing 271, flexible arms 273b are then deflected inwardly into recesses 274b. With flexible arms 273b deflected into recesses 274b, plunger rod 273 is free to move distally to administer the contents of syringe 272.

[0087] 28A and 28B show another embodiment according to the present disclosure. The device 280 may include a housing 281, a syringe 282, and a plunger rod 283. As shown in FIG. 28A and 28B, the housing 281 may include a flange 281a. The housing 281 may also include a trigger 284. FIG. 28A and 28B show an internal view of the device 280. The trigger 284 may extend through the interior of the housing 281, for example, through the flange 281a. With reference to FIG. 28A, a portion of the trigger 284 may extend distally from the flange 281a. The flange 281a may include a plurality of slots 284a. The slots 284a may move the trigger 284 within the flange 281a. In a pre-injection state, as shown in FIG. 28A, a portion of the trigger 284 abuts the plunger rod 283 and prevents pre-ejection of the contents of the syringe 282. To initiate an injection, a user may press thumb pad 283a distally toward housing 281 while squeezing a portion of trigger 284 extending distally from flange 281a. For example, a user may push a portion of trigger 284 proximally into flange 281a. When a portion of trigger 284 is squeezed, a plurality of slots 284a may guide trigger 284 away from plunger rod 283, allowing plunger rod 283 to move distally into housing 281 (FIG. 28B).

[0088] 29A and 29B show another embodiment according to the present disclosure. The device 290 may include a housing 291, a syringe 292, a plunger rod 293, and an internal rod 294. As shown in FIG. 29A, the device 290 may include a blocking component 300. The blocking component 300 may correspond to the blocking components 62 and 82 as described herein. The blocking component 300 may include a plurality of flexible arms 302. The plurality of flexible arms 302 may correspond to the plurality of flexible arms 63 and 83 as described herein. The internal rod 294 may include a button 294a extending proximally from a thumb pad 293a of the plunger rod 293. The internal rod 294 may also include a distal block 294b. In the pre-injection state, as shown in FIG. 29A, the distal block 294b can be positioned above the spring 295 and within the flexible portion 293b of the plunger rod 293. The distal block 294b can abut the flexible portion 293b and prevent the movement of the multiple flexible arms 302. This pre-injection state can prevent pre-ejection of contents from the syringe 292. To initiate an injection, the user can push the button 294a distally into the interior of the plunger rod 293. Pushing the button 294a can move the interior rod 294 and the distal block 294b distally against the spring 295 toward the syringe 292. As shown in FIG. 29B, the distal block 294b is moved distally away from the flexible portion 293b of the plunger rod 293. The multiple flexible arms 302 may then bend inwardly toward the flexible portion 293b, allowing the plunger rod 293 to then move distally into the housing 291 and syringe 292, expelling the contents of the syringe 292.

[0089] 30A-30 show another embodiment according to the present disclosure. The device 400 may include a housing 402, a syringe 404, a plunger rod 406, a rear cap 408, and a spring 410 surrounding a proximal portion of the syringe 404. As shown in FIG. 30A, the proximal portion of the housing 402 may include a plurality of recesses 403a, 403b, and the rear cap 408 may include a plurality of distal arms 409a, 409b. The recesses 403, 403b may be configured to receive the distal arms 409a, 409b. To couple the rear cap 408 to the housing 402, the first distal arm 409a may hook within the recess 403a, and the second distal arm 409b may hook within the recess 403b. The syringe 404 may also include a syringe flange 405. As shown in FIG. 30A, the syringe flange 405 can be located between a portion of the finger flange 408 and a portion of the housing 402. For example, a proximal end of the syringe flange 405 can abut a distal inner surface of the finger flange 405, and a distal end of the syringe flange 405 can abut a proximal end of the housing 402. With reference to FIGS. 30A and 30C, the plunger rod 406 can include a first portion 407a and a second portion 407b. The first portion 407a can have a first diameter and the second portion 407b can have a second diameter. The first diameter can be greater than the second diameter. In other examples, the first diameter can be less than the second diameter. In some examples, the plunger rod has a first width and a second width, and the first width is greater than the second width. In other examples, the first width can be less than the second width. 30C, the plunger rod 406 includes a third portion 407c, the diameter of which is greater than the diameter of the second portion 407b. The finger flange 408 may be of any suitable size, shape, and / or configuration that surrounds a portion of the plunger rod 406.

[0090] Referring to FIG. 30B, the finger flange 408 may include a first component 412a and a second component 412b. The first component 412a may include a first hook 414a, and the second component 412b may include a second hook 414b. As shown in FIG. 30B, the first hook 414a and the second hook 414b may abut and / or surround a portion of the plunger rod 406. In a pre-injection state, as shown in FIGS. 30A and 30B, the finger flange 408 may surround the first portion 407a of the plunger rod 406. The finger flange 408 may also include a spring (not shown) configured to separate the first component 412a and the second component 412b (FIG. 30B). Movement of the finger flange 408 may be prevented by a spring and engagement of the first and second hooks 414a, 414b with the first portion 407a of the plunger rod 406. To initiate an injection, a user may depress the plunger rod 406 on a thumb pad (not shown) in a distal direction toward the housing 402. During an injection, the plunger rod 406 may be positioned within the housing 402 such that the second portion 407b of the plunger rod 406 is received within the finger flange 408. In embodiments in which the second portion 407b may have a diameter smaller than that of the first portion 407a, the hooks 414a, 414b may not abut a portion of the plunger rod 406. For example, as shown in FIG. 30D, there may be a space between the finger flange 408 and the plunger rod 406, allowing the plunger rod 406 to move distally into the interior of the housing 402 and the syringe 404 and expel the contents from the syringe 404. At the end of administration, as shown in FIG 30A, the user may maintain depression of the thumb pad, allowing the plunger rod 406 to partially retract rearward, i.e., proximally, from the housing 402. The spring 410 is then released, allowing the syringe 404 to move proximally toward the distal surface of the finger flange 408.

[0091] 31 and 32A-32F show another embodiment according to the present disclosure. The features and mechanisms described with respect to FIG. 31 and 32a-32F may be used and combined with the features of device 400 as described above and shown in FIG. 30A-30D. FIGS. 31, 32A, 32B, 32E, and 32F show a top view of device 500. Device 500 may include a housing (not shown), a finger flange 502, a thumb pad 504, and a slider 506. Thumb pad 504 may include a plurality of clips 508a, 508b. Slider 506 may include an opening 510 for receiving a plunger rod (not shown). Clips 508a, 508b may couple thumb pad 504 to the plunger rod in opening 510. The plunger rod utilized in device 500 and with the features of device 500 described herein may include various geometric features, e.g., multiple recesses as shown in FIG. 19B. Referring to FIGS. 31, 32A, 32B, 32E, and 32F, to initiate an injection, a user may push the plunger rod distally. During an injection, as described above with respect to device 400 of FIGS. 30A-30D, as the geometry of the plunger rod changes, e.g., in diameter and / or width, a spring may push slider 506, e.g., to the right. As slider 506 is displaced, ramps 512a, 512b of slider 506 may push clips 508a, 508b. Ramps 512a, 512b may have a width greater than a portion of slider 506 that is initially located between clips 508a, 508b. Ramps 512a, 512b can press against clips 508a, 508b, deflecting clips 508a, 508b outward. This unlocks thumb pad 504 from the plunger rod and simultaneously allows a syringe (not shown) to move proximally, deflecting clips 508a, 508b outward and locking them into a locked out position inside the housing. Figure 31 is a top view of device 500 at the end of administration. Figures 32A-32D show slider 506 including recess 520.The recess 520 may be shaped as a C-block, i.e., to have a C-shape. The recess 520 may interact with portions of the housing to prevent the slider and / or the syringe from moving in a proximal direction. These features may eliminate the need for the user to apply extra force at the end of an injection to activate a safety mechanism that locks out the syringe. The spring 514 may be located on the side of the slider 506 that includes the ramps 512a, 512b. The spring 514 may release its stored energy and push the syringe proximally as the thumb pad 504 and plunger rod separate from each other.

[0092] The components of the device herein may be made of any suitable material, and each component may be made of the same or different material as the other components. For example, one or more components may be made of a material including a polymer, such as plastic. In some embodiments, one or more components may include a number of different materials, such as glass, plexiglass, any other suitable polymer or copolymer, plastic, or rubber. In some embodiments, a portion of the product container configured to contain the formulated drug substance may be made of a transparent or translucent material. In some embodiments, the components of the device may be made of materials each having similar or different hardness. In some embodiments, the components may include an elastic material. For example, components that may be flexible or flexible may be made of a material that has some degree of flexibility, for example, to allow bending. One or more of the materials listed above (e.g., plastic, rubber, polymer, or copolymer) may have such properties.

[0093] The above description and examples are illustrative and are not intended to be limiting. Numerous modifications and / or alterations may be made by one of ordinary skill in the art without departing from the intended scope of the present invention. For example, as has been referenced, aspects of the above-described embodiments may be used in any suitable combination with one another. In addition, parts of the above-described embodiments may be removed without departing from the scope of the present invention. Furthermore, modifications may be made to adapt a particular situation or aspect to the teachings of the various embodiments without departing from such scope. Many other embodiments will be apparent to those of ordinary skill in the art upon reviewing the above description.

[0094] Implementations of the present disclosure may include the following features. Item 1. A drug delivery device comprising: Housing and a product container disposed within the housing; a plunger rod partially disposed within the product container; a thumb pad configured to receive a portion of the plunger rod; A drug delivery device, wherein the thumb pad and the plunger rod are configured to transition from a first state to a second state, wherein in the first state, the plunger rod is prevented from moving in a proximal direction and in the second state, the plunger rod is free to move in a proximal direction.

[0095] Item 2. The drug delivery device of item 1, wherein the thumb pad includes an extension projecting distally from the thumb pad. Item 3. The drug delivery device of item 2, wherein the housing has a shoulder, and in the first condition, the shoulder protrudes radially inward to inhibit movement of the product container.

[0096] Item 4. The drug delivery device of item 3, wherein in the second condition, the extension of the thumb pad is configured to deflect the shoulder radially outwardly to allow the product container to move in a proximal direction.

[0097] Item 5. The drug delivery device of item 4, wherein the product container and a needle attached to a distal end of the product container are retracted in the proximal direction into the housing such that the needle is located proximate the distal end of the housing.

[0098] Item 6. The drug delivery device of item 5, wherein a distance that the product container is proximally retracted into the housing in the second state is substantially equal to a length that the needle extends distally from the housing in the first state.

[0099] Item 7. The drug delivery device of item 1, wherein the proximal end portion of the plunger rod includes a flange and the thumb pad includes a recess configured to receive the flange.

[0100] Item 8. The drug delivery device of item 1, wherein the plunger rod abuts an inner distal surface of the thumb pad in the second state. Item 9. The drug delivery device of item 1, wherein in the second state, audible feedback is generated when a portion of the plunger rod abuts an inner distal surface of the thumb pad.

[0101] Item 10. The drug delivery device of item 1, wherein the housing includes a surface configured to deflect a portion of the thumb pad outwardly to release a proximal portion of the plunger rod when transitioning to the second state.

[0102] Item 11. The drug delivery device of item 1, wherein the housing includes a notch configured to engage a portion of the thumb pad to couple the thumb pad to the housing in the second state.

[0103] Item 12. The plunger rod includes a first portion and a second portion, 2. The drug delivery device of claim 1, wherein in a first state, the first portion is adjacent to the second portion and in a second state, the first portion has a diameter larger than a diameter of the second portion such that the second portion is folded inside the first portion.

[0104] Item 13. The drug delivery device of item 1, further comprising a rotor configured to be located proximate to a proximal end of the product container in a first state and configured to surround the proximal end of the product container in a second state.

[0105] Item 14. The drug delivery device of item 1, wherein the plunger rod includes a first portion and a second portion, a distal end of the second portion is coupled to a proximal end of the first portion, and the housing includes a proximal extension, and in a first state, the proximal extension abuts the distal end of the first portion to prevent the product container from moving proximally away from the housing.

[0106] Item 15. The drug delivery device of item 14, wherein in a second condition, the proximal extension is deflected away from the distal end of the first portion to allow the product container to move proximally away from the housing and into the interior of the thumb pad.

[0107] Item 16. The drug delivery device of item 1, wherein the proximal end of the housing includes a rear cap configured to surround the proximal end of the product container. Item 17. A drug delivery device comprising: Housing and a product container disposed within the housing; a needle extending from a distal end of the product container; a plunger rod for dispensing a product from the product container, the plunger rod including a first recess at a distal portion of the plunger rod and a second recess at a proximal portion of the plunger rod; a blocking component at a proximal end of the housing, the plunger rod being slidably received within the blocking component, the blocking component including a flexible arm; and and a needle cover at least partially disposed within the housing.

[0108] Item 18. The drug delivery device comprises: Item 18. The drug delivery device of item 17, configured to transition from a first state in which a proximal end of the needle cover abuts the flexible arm and the flexible arm is aligned with the first recess, to a second state in which the flexible arm is deflected radially outward, and to a third state in which the flexible arm is aligned with the second recess and the proximal end of the needle cover is located distal to the flexible arm.

[0109] Item 19. The drug delivery device of item 17, wherein the second recess has a smaller diameter than the first recess. Item 20. The drug delivery device of item 17, wherein the housing includes a ledge for abutting a portion of the needle cover to prevent proximal movement of the needle cover into the interior of the housing.

[0110] Item 21. The drug delivery device of item 18, wherein in the first condition, the needle cover extends distally of the housing to cover the needle. Item 22. The drug delivery device of item 18, wherein in the second state, the proximal end of the needle cover abuts a distal portion of the blocking component.

[0111] Item 23. The drug delivery device of item 18, wherein in the first state, the flexible arm restricts movement of the plunger rod, and in the second state, the deflected flexible arm allows movement of the plunger rod.

[0112] Item 24. The drug delivery device of item 17, further comprising an inner rod configured to be secured within the plunger rod. Item 25. The drug delivery device of item 24, wherein the inner rod includes a distal block configured to abut a portion of the plunger rod to prevent the plunger rod from moving in a distal direction.

[0113] Item 26. The drug delivery device of item 25, wherein a distal end of the plunger rod includes a flexible arm configured to abut a portion of the inner rod to prevent the plunger rod from moving in a distal direction.

[0114] Item 27. The drug delivery device of item 25, wherein the plunger rod includes a flexible portion, and in a first state, the distal block prevents the flexible portion from compressing, and in a second state, the distal block moves away from the flexible portion and allows the flexible portion to compress.

[0115] Item 28. The drug delivery device of item 17, wherein the housing includes a finger flange and a button mechanism configured to abut a portion of the plunger rod in a first state and to deflect away from the plunger rod in a second state.

[0116] Item 29. A drug delivery device comprising: Housing and A plunger rod; a needle cover disposed at least partially within the housing; a rotating component having a track extending along an outer surface of the rotating component; A drug delivery device, wherein a portion of the plunger rod extends through a central region of the rotating component, the rotating component being located radially inward of a proximal portion of the needle cover, and a protrusion of the needle cover is configured to engage the track of the rotating component and move along the track of the rotating component as the drug delivery device transitions from a first state, to a second state, and to a third state.

[0117] Item 30. A product container for containing a liquid drug; a stopper disposed within the product container, the stopper being moved distally by distal movement of the plunger rod; 30. The drug delivery device of claim 29, wherein in the first state, the protrusion engages a first end of the track and distal movement of the plunger rod is restricted.

[0118] Item 31. The drug delivery device of item 30, wherein in the second state, the protrusion engages an intermediate portion of the track to permit distal movement of the plunger rod and the needle cover is positioned further proximally within the housing relative to a position of the needle cover in the first state.

[0119] Item 32. The drug delivery device of item 31, wherein in the third state, the protrusion engages a second end of the track and the needle cover is located further distally within the housing and extends from a distal end of the housing relative to a position of the needle cover in the second state.

[0120] Item 33. The drug delivery device of item 32, wherein in the third state, the needle cover is located further distally within the housing relative to the position of the needle cover in the first state, and the needle cover extends from the distal end of the housing in the first state and in the third state.

[0121] Item 34. A drug delivery device comprising: a housing including a flexible tab; a syringe disposed within the housing; a plunger rod including a stopper for administering a product contained within the syringe; a needle cover at least partially disposed within the housing, the needle cover including a notch; a ring including a ledge positioned about a proximal end of the syringe; the drug delivery device is configured to transition between a first state, a second state, and a third state; In the second state, the needle cover is positioned further proximally within the housing compared to the first state and the third state, the proximal end of the needle cover is configured to push the flexible tab of the housing outward, and the notch of the needle cover engages with the ledge of the ring, a drug delivery device.

[0122] Item 35. The drug delivery device of item 34, wherein in the third state, the needle cover and the ring are located distal to the flexible tab, and the flexible tab limits movement of the needle cover in a proximal direction.

[0123] Item 36. The drug delivery device of item 35, wherein in the first state, the needle cover is located distal to the ring. Item 37. A drug delivery device comprising: Housing and a product container disposed within the housing; a plunger rod partially disposed within the product container, the plunger rod including a first portion and a second portion, the first portion configured to receive the second portion; A drug delivery device, wherein the first and second portions of the plunger rod are configured to transition from a first state to a second state, wherein in the first state, the second portion of the plunger rod is prevented from moving in a proximal direction and wherein in the second state, the second portion of the plunger rod is free to move in a proximal direction.

[0124] Item 38. The drug delivery device of item 37, wherein the first portion includes a thumb pad. Item 39. The drug delivery device of item 38, wherein the thumb pad includes a recess configured to receive the second portion of the plunger rod.

[0125] Item 40. The drug delivery device of item 37, wherein in the second state, the second portion of the plunger rod moves proximally into the first portion of the plunger rod.

[0126] Item 41. The drug delivery device of item 37, wherein the plunger rod includes a flexible portion. Item 42. The drug delivery device of item 37, wherein the second portion of the plunger rod is removably coupled to the first portion of the plunger rod.

Claims

1. 1. A drug delivery device comprising: Housing and a product container disposed within the housing; a needle extending from a distal end of the product container; a plunger rod for dispensing product from the product container, the plunger rod including a first recess in a distal portion of the plunger rod and a second recess in a proximal portion of the plunger rod; a blocking component at a proximal end of the housing, the plunger rod being slidably received within the blocking component, the blocking component including flexible arms configured to be received in the first recess and the second recess of the plunger rod; a needle cover disposed at least partially within the housing and surrounding the product container to restrict proximal movement of the plunger rod.

2. The drug delivery device comprises:

2. The drug delivery device of claim 1, configured to transition from a first state in which the proximal end of the needle cover abuts the flexible arm and the flexible arm is aligned with the first recess, to a second state in which the flexible arm is deflected radially outward, and to a third state in which the flexible arm is aligned with the second recess and the proximal end of the needle cover is located distal to the flexible arm.

3. The drug delivery device of claim 1 , wherein the second recess has a smaller diameter than the first recess.

4. The drug delivery device of claim 1 , wherein the housing includes a ledge for abutting a portion of the needle cover to prevent proximal movement of the needle cover into the housing.

5. The drug delivery device of claim 2 , wherein in the first state, the needle cover extends distally of the housing to cover the needle.

6. The drug delivery device of claim 2 , wherein in the second state, the proximal end of the needle cover abuts a distal portion of the blocking component.

7. 3. The drug delivery device of claim 2, wherein in the first state, the flexible arm restricts movement of the plunger rod, and in the second state, the bent flexible arm allows movement of the plunger rod.

8. The drug delivery device of claim 1 , further comprising an inner rod configured to be secured within the plunger rod.

9. 9. The drug delivery device of claim 8, wherein the inner rod includes a distal block configured to abut a portion of the plunger rod to prevent the plunger rod from moving in a distal direction.

10. 10. The drug delivery device of claim 9, wherein the distal end of the plunger rod includes a flexible arm configured to abut a portion of the inner rod to prevent the plunger rod from moving distally.

11. 10. The drug delivery device of claim 9, wherein the plunger rod includes a flexible portion, and in a first state, the distal block prevents the flexible portion from compressing, and in a second state, the distal block moves away from the flexible portion, allowing the flexible portion to compress.

12. 2. The drug delivery device of claim 1, wherein the housing includes a finger flange and a button mechanism configured to abut a portion of the plunger rod in a first state and to bend away from the plunger rod in a second state.

Images