Autoinjector with three-position needle guard

Abstract

An injector includes a housing having a proximal end and a distal end opposite the proximal end. The housing extends along a longitudinal axis. A medicament container is disposed within the housing, the medicament container contains a medicament. A needle is coupled to a proximal end of the medicament container and in fluid communication with the medicament container. A trigger mechanism includes a needle guard retractably coupled to the proximal end of the housing and is movable along the longitudinal axis between an extended position, an intermediate position, and a retracted position. A cap is removably coupled to the proximal end of the housing and the needle guard is in the intermediate position when the cap is coupled to the proximal end of the housing.

Description

TITLE

[0001] Autoinjector with Three-Position Needle GuardCROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 609,481 filed December 13, 2023, titled “Autoinjector with Three-Position Needle Guard”, which is incorporated by reference herein in its entirety.TECHNICAL FIELD

[0003] The present disclosure generally relates to medicament injection devices and, in some embodiments, to a needle-assisted injector with a three-position needle guard.SUMMARY

[0004] In one embodiment, there is an injector including a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis, a medicament container disposed within the housing, the medicament container containing a medicament, a needle coupled to a proximal end of the medicament container and in fluid communication with the medicament container, a trigger mechanism comprising a needle guard retractably coupled to the proximal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position; and a cap removably coupled to the proximal end of the housing, the needle guard is in the intermediate position when the cap is coupled to the proximal end of the housing.

[0005] In some embodiments, the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position In some embodiments, the first length is greater than the second length. In some embodiments, the first length is approximately 21 mm. In some embodiments, the second length is approximately 17 mm.

[0006] In some embodiments, the needle guard is urged distally along the longitudinal axis from the extended position to the intermediate position when the cap is coupled to the housing In some embodiments, the needle guard covers a portion of the needle in the intermediate position. In some embodiments, a needle shield coupled to the needle and configured to cover at least a portion of the needle extends distally through an aperture of the cap when the cap is coupled to the housing. In some embodiments, the needle shield is decoupled from the needle by the cap when the cap is decoupled from the housing. In some embodiments, the needle guard moves from the extendedposition to the retracted position in response to a user pressing the needle guard against an injection site. In some embodiments, the needle guard moves from the retracted position to the extended position when the user removes the injector from the injection site. In some embodiments, the needle guard is moved from the retracted position to the extended position by a biasing member. In some embodiments, the needle guard is prevented from moving relative to the housing when moved from the retracted position to the extended position.

[0007] In some embodiments, the injector further includes a biasing member, the biasing member configured to urge the needle guard distally along the longitudinal axis to the extended position when the cap is not coupled to the housing. In some embodiments, the needle guard covers a full length of the needle in the extended position.

[0008] In some embodiments, the trigger mechanism further includes a ram configured to move a plunger engageable with a distal end thereof relative to the medicament container, a trigger member configured to engage the ram and prevent movement thereof when the needle guard is in the extended position, and an energy source engaging a distal end of the ram, the energy source configured to move the ram distally relative to the housing. In some embodiments, movement of the needle guard from the extended position to the retracted position disengages the trigger member from the ram, thereby allowing the energy source to move the plunger relative to the medicament container to expel the medicament through the needle.

[0009] In another embodiment, there is an injector including a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis, a medicament container disposed within the housing, the medicament container containing a medicament, a needle coupled to a distal end of the medicament container and in fluid communication with the medicament container, a trigger mechanism comprising a needle guard retractably coupled to the distal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position, and a cap removably coupled to the distal end of the housing. In some embodiments, the needle guard is in the intermediate position when the cap is coupled to the distal end of the housing. In some embodiments, the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position. In some embodiments, the first length is greater than the second length. In some embodiments, the needle guard is urged distally along the longitudinal axis from the extended position to the intermediate position when the cap is coupled to the housing.

[0010] In another embodiment, there is a method of delivering a medicament to a subject, the method including providing an injector, the injector including a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis, a medicament container disposed within the housing, the medicament container containing the medicament, a needle coupled to a distal end of the medicament container and in fluid communication with the medicament container, and a trigger mechanism comprising a needle guard retractably coupled to the distal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position, and coupling a cap to the housing thereby moving the needle guard distally along the longitudinal axis from the extended position to the intermediate position.

[0011] In some embodiments, the method of delivering a medicament to a subject further includes removing the cap from the housing thereby allowing a biasing member disposed in the housing to move the needle guard distally along the longitudinal axis from the intermediate position to the extended position, pressing the needle guard against an injection site of the subject, thereby moving the needle guard from the extended position to the retracted position, and removing the injector from the injection site, thereby allowing the biasing member to move the needle guard distally along the longitudinal axis from the retracted position to the extended position. In some embodiments, the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position. In some embodiment, the first length is greater than the second length. In some embodiments, the first length is approximately 21 mm and the second length is approximately 17 mm.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The foregoing summary, as well as the following detailed description of embodiments of the injection device, will be better understood when read in conjunction with the appended drawings of exemplary embodiments. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.

[0013] In the drawings:

[0014] Fig. 1 is a perspective view of an injection device in a pre-firing state in accordance with a first exemplary embodiment of the present invention;

[0015] Fig 2 is a front cross-sectional view of the injection device of Fig 1 with the cap removed;

[0016] Fig. 3 is a side cross-sectional view of the injection device of Fig. 1 taken about a plane 90 degrees from the plane of Fig. 2;

[0017] Fig. 4A is a front view of a front housing of the injection device of Fig. 1;

[0018] Fig. 4B is a side view of the front housing of the injection device of Fig. 1;

[0019] Fig. 5 is a perspective view of a medicament container of the injection device of Fig. 1 ;

[0020] Fig. 6 is a perspective view of a needle guard of the injection device of Fig. 1;

[0021] Fig. 7 is a perspective view of a ram of the injection device of Fig. 1;

[0022] Fig. 8 is a perspective view of the trigger mechanism of the injection device of Fig. 1;

[0023] Fig. 9 is a front cross-sectional view of the injection device of Fig. 1 in a fired state;

[0024] Fig. 10 is a side cross-sectional view of the injection device of Fig. 1 in a fired state, taken about a plane 90 degrees from the plane of Fig. 9;

[0025] Fig. 11 is a front cross-sectional view of the injection device of Fig. 1 in a locked-out state;

[0026] Fig. 12 is a side cross-sectional view of the injection device of Fig. 1 in a locked-out state, taken about a plane 90 degrees from the plane of Fig. 11;

[0027] Fig. 13 is a front cross-sectional view of a cap of the injection device of Fig. 1;

[0028] Fig 14 is a front cross-sectional view of an injection device in a pre-firing state in accordance with a second exemplary embodiment of the present invention;

[0029] Fig. 15A is a front partial cross-sectional view of the injection device of Fig. 1 with the cap on and the needle guard in an intermediate position;

[0030] Fig. 15B is a front view of the injection device of Fig. 1 with the cap off and the needle guard in an extended position; and

[0031] Fig. 15C is a front view of the injection device of Fig. 1 with the cap off and the needle guard in a retracted position.DETAILED DESCRIPTION

[0032] Referring to the drawings in detail, wherein like reference numerals indicate like elements throughout, there is shown in Figs. 1-13 an injection device, generally designated 100, in accordance with a first exemplary embodiment of the present invention.

[0033] Fig. 1 shows an exemplary injection device 100 according to a first exemplary embodiment of the present disclosure. It is noted that, in the context of this disclosure, the terms “distal” and “proximal” are used in reference to the position of the injection device 100 relative to a user of the injection device 100 when held by a user. Accordingly, a feature located distal to a second feature would be further from the user (i e , toward an injection end of the injection device 100) and vice versa. A person having ordinary skill in the art will understand that alternative embodiments employing certain features herein may be configured as needle-free jet injectors, needle-assisted jetinjection devices, powered injectors, low-pressure auto-injectors or other mechanized injectors. According to certain embodiments, injection device 100 is a one-time disposable injector. In certain embodiments, injection device 100 may be modified to provide multiple and / or variable dosings upon repeated injections. According to certain embodiments, injection device 100 is a one-time disposable injector with a lock-out feature. For example, injection device 100 may facilitate an injection of medicament stored within injection device 100 and may include a locking feature that prevents a user from attempting to use injection device 100 again after the medicament has been dispensed. In one embodiment, the locking feature is activated upon dispensing of the medicament and not upon use of injection device 100. For example, the locking feature may be activated, thus preventing injection device 100 from a subsequent attempted use by a user, even in the case where the injection device 100 was not actually used by a user for an injection, but where a trigger mechanism 108 was inadvertently activated (e.g., during transport, handling, etc. of the device) and the medicament was dispensed. Operation of injection device 100, including the locking feature, is described in further detail below.

[0034] According to certain embodiments, injection device 100 may deliver any suitable liquid drug or medicament. Further, injection device 100 may allow the injection to be administered by individuals that do not have formal training (e.g., self-administered or administered by another individual family member or other caregiver who may not be a formally trained healthcare provider). Accordingly, injection device 100 may be useful in situations where self-injections / caregiver administered injections would be beneficial, including, but not limited to, drug overdose or alcohol dependence. Further, injection device 100 may be used to inject a wide range of drugs. For example, injection device 100 may be used to inject drugs, water-soluble medicaments, peptides, proteins, depot formulations and oil-soluble medicaments. In one embodiment, the injection device 100 is designed to cause a powerful and smooth expulsion of a medicament, which may be necessary for viscous formulations, including but not limited to biologies. In certain embodiments, the injection device 100 is designed to administer the medicament very rapidly.

[0035] Injection device 100 may include a needle guard with three positions. When a cap is coupled to the injection device, the needle guard 100 may be partially retracted into an intermediate position. An intermediate position may allow for a variety of needles to be used with varying lengths. The ability to use many needles with a single injector can reduce manufacturing costs by allowing the same parts to be used in multiple applications, which can reduce downstream costs to patients and other consumers.

[0036] The injection device 100 includes a housing 102 having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis LA The injection device 100 mayfurther include various components and / or assemblies housed within housing 102. As shown in Figs. 2, 3 and 9-12, these components may include a medicament container 104, a needle 106, and a trigger mechanism 108 Housing 102 may be a single piece component, or alternatively, housing 102 may be a multiple piece assembly coupled together, for example, via a snap-fit connection, a press-fit connection, a threaded engagement, adhesives, welding, or the like.

[0037] In one embodiment, the housing 102 includes a front sub-assembly and a rear subassembly coupled together, for example, via a snap-fit connection, a press-fit connection, a threaded engagement, adhesives, welding, or the like. The front sub-assembly may include a needle guard 110, a biasing member 112, a bushing 114, and a front housing 116. The rear sub-assembly may include a rear cap 118, an energy source 120, a ram 122, the trigger mechanism 108, and a rear housing 124. Providing two sub-assemblies may increase the ability to modulate components in each sub-assembly to allow customization and repeatability in manufacturing.

[0038] As shown in Figs. 2, 3 and 9-12, in one embodiment, the medicament container 104 is disposed at least partially within the front housing 116 The medicament container 104 may contain a medicament comprising an opioid antagonist or a pharmaceutically acceptable salt thereof. The medicament container 104 may be disposed within a sleeve 126 of the front housing 116 when disposed in the injection device 100. The front housing 116 may be coupled to the distal end of the housing 102 via, for example, a snap-fit connection, a press-fit connection, a threaded engagement, adhesives, welding, or the like. According to certain embodiments, injection device 100 may be configured to inject medicament stored within a prefilled syringe. Prefilled syringes that are manufactured by a blown glass process may have significant dimensional tolerances and unevenness. Accordingly, features of front housing 1 16 may serve to accommodate the shape irregularities and to properly position and locate a prefilled syringe within injection device 100. Other medicament containers such as prefilled syringes manufactured with polymers may also be accommodated.

[0039] Medicament container 104 may include a cylindrical body 166 configured to hold at least 1 mL of medicament. In some embodiments, the cylindrical body 166 may hold at least 1.5 mL, at least 2 mL, at least 2.5 mL, or at least 3 mL. As shown in Fig. 5, a plunger 130 is provided in the medicament container 104. Plunger 130 may be in association with a ram 122 of the rear subassembly, as described in more detail below. During an injection, ram 122 is urged distally along the longitudinal axis LA by an energy source 120 to displace plunger 130 distally through medicament container 104, dispensing the medicament through needle 106. Figs. 2-3 show injection device 100 in a pre-firing state. The operation of injection device 100, including its various stages and positions, is described in further detail below

[0040] A sleeve 126 is configured to hold the medicament container 104, which may include a needle 106 extending from a distal end thereof. The needle 106 may be in fluid communication with the medicament container 104. A bushing 1 14 may be disposed within the sleeve 126 to accommodate a proximal end of the medicament container 104. As shown in Fig. 5, the medicament container 104 may include a rim 164 that engages the bushing 114. The rim 164 may be generally circular and have a circumference greater than that of the cylindrical body 166. The bushing 114 may be fixed relative to the housing 102 thereby preventing the medicament container 104 from moving distally relative to the housing 102 during a firing. In certain embodiments, medicament container 104 may include, for example, a separate glass ampule and a needle, or a pre-filled syringe. In one embodiment, sleeve 126 may include an integral medicament container. The needle 106 may be coupled to the medicament container 104 by threaded communication, snap fit communication, friction fit, or any suitable coupling configuration.

[0041] Additionally, as shown in Figs. 4A-4B, sleeve 126 may include various features, such as projections 128, configured to couple the front housing 1 16 to the housing 102 For example, projections 128 may be concentrically symmetrical and configured to engage openings in housing 102 to the front housing 116 to the housing 102. In one embodiment, projections 128 are disposed on legs 129, which may be concentrically symmetrical and configured to engage with features of the housing 102. Additionally, sleeve 126 may include locking features, such as locking projections 131, disposed on legs 133, which may be concentrically symmetrical, and may be configured to engage with features of needle guard 110 resulting in locking out injection device 100 to prevent a user from attempting to use an already -fired injection device 100, as discussed in more detail below.

[0042] In one embodiment, housing 102 includes openings configured to engage with sleeve 126 to couple and secure sleeve 126 to housing 102 and includes at least one window that may provide a visual indication of whether injection device 100 has been fired. For example, in a pre-firing state, the window may allow a user to see the medicament container 104, along with the stored medicament, and in a fired state, the window shows one or more internal components, such as a portion of trigger mechanism 108 or ram 122, which may be a color specifically selected to alert the user that injection device 100 has been fired, and is, in one embodiment, sufficiently different from other colors visible to a user (in one embodiment, having ordinary eyesight) on injection device 100 prior to firing, so as to be conspicuously different to, or contrast from, any other colors present or significantly present. For example, in one embodiment, the color differs from all the other components of injection device 100 pre-firing, or visible by the user pre-firing, so as to be conspicuous (e.g., introducing an entirely new color family) In one embodiment, the new color appearing after firing is from a non-analogouspart of the color wheel, or may contrast, or may be a complementary color, with respect to the colors visible on injection device 100. In one embodiment, the new color signifies caution, such as red or orange, etc. In one embodiment, the colors visible on injection device 100 in the pre-firing condition, and, in one embodiment, including when cap 136 is on and / or off injection device 100, are grays and blues, for instance. In one embodiment, when injection device 100 is fired, the color red is introduced. In one embodiment, this new color may be introduced after firing but prior to needle guard 110 being locked out in the extended position.

[0043] As shown in Fig. 5, needle 106 may include an injecting tip 106a that is configured to penetrate the skin of a user and a hollow bore 106b that is in fluid communication with medicament container 104 to facilitate delivery of medicament from medicament container 104 to a user during an injection. In one embodiment, the needle 106 may be 22 gauge. In some embodiments, the needle 106 is between 22 and 29 gauge. In some embodiments, the needle 106 may be between 25 and 28 gauge, and, in other embodiments, is around 27 gauge, but alternatively other needle gauges may be used where the other components are cooperatively configured to produce the desired injection In one embodiment, the needle 106 is a 5 / 8” staked needle. In some embodiments, the needle 106 is a staked needle between 1 / 2” and 3 / 4” long. In some embodiments, the needle 106 may be between 9 / 16” and 11 / 16”.

[0044] In some embodiments, thin-walled needles may be used. A thin-walled needle may have the same outer diameter as a staked or “regular wall” needle of the same gauge but allow for flow volume of a needle at least one gauge larger. For example, a 22-gauge thin-walled needle may allow for the same flow volume as a 21 -gauge regular wall needle. A thin-walled needle may have a wall thickness less than 0.05 mm. A thin-walled needle may have a wall thickness less than 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, or 0.09 mm. A thin-walled needle may have a wall thickness between 0.02 mm and 0.09 mm, between 0.03 mm and 0.08 mm, between 0.04 mm and 0.07 mm, and between 0.05 mm and 0.06 mm. In some embodiments, thin-walled needles may be used without risk of bending when injection device 100 is configured to act with manual needle insertion prior to injection.

[0045] As shown in Figs. 2-3, in one embodiment, injection device 100 includes a needle guard 110 slidably mounted at least partially within the distal end of housing 102. The needle guard 110 may be configured to engage trigger mechanism 108 to actuate firing of injection device 100. As shown in Figs. 2, 3 and 9-12, in one embodiment, needle guard 110 is slidably movable relative to housing 102 between an extended (e.g., a distal, protective) position and a retracted (e.g., proximal) position, respectively In the extended position, needle guard 110, in one embodiment, covers needle106, and in the retracted position, needle 106 is not covered by needle guard 110 and is thereby exposed. For example, Figs. 2-3 show needle guard 110 in the extended position, and Figs. 9-10 show needle guard 1 10 in the retracted position. As shown in Figs. 2-3, in one embodiment, needle guard 110 is resiliently biased toward the extended position via the biasing member 112, which may be disposed, for example, between a distal surface of front housing 116 and an interior surface of a distal end of needle guard 110. In some embodiments, the biasing member 112 includes a compression spring; however, other suitable energy sources may be used, such as an elastomer or compressed-gas spring, or a gas generator, or other suitable energy storage members.

[0046] As shown in Figs. 9-10, when the needle guard 110 is in the retracted position, the needle 106 extends from the housing 102 a length X. Length X may be at least 5 mm. In some embodiments, length X is at least 2 mm, at least 3 mm, at least 4 mm, at least 6 mm, at least 7 mm, at least 8 mm, at least 9 mm or at least 10 mm. In some embodiments, length X is between 2 mm and 10 mm, between 3 mm and 9 mm, between 4 mm and 8 mm, or between 5 mm and 7 mm.

[0047] Injection device 100 may be configured to deliver the volume of medicament subcutaneously to the user. In some embodiments, injection device 100 may be configured to deliver the volume of medicament intramuscularly to the user. Length X may be determined based on the specific application of the injection device 100. For example, length X may be greater for intramuscular delivery than subcutaneous.

[0048] As shown in Fig. 6, in an embodiment, needle guard 110 includes a distal portion 132 and legs 134 extending proximally from the distal portion 132. In an embodiment, the distal portion 132 of needle guard 110 includes a skin-contacting member at a distal surface thereof. The distal portion 132 may be shaped generally the same as the housing 102. Distal portion 132 includes an opening (not shown) through which needle 106 can pass.

[0049] Needle guard 110 may further include projections 132a, as shown in Fig. 6. Projections 132a may engage engagement features 138 of cap 136, as shown in Fig. 13, so that needle guard 110 cannot be proximally displaced when engaged with engagement features 138 of cap 136. In an embodiment, the needle guard 1 10 includes a stop surface 140. The stop surface 140 may be configured to abut an inside surface of the front housing 116 so as to limit the proximal displacement of needle guard 110. For example, as needle guard 110 is proximally displaced under a force applied by a user during an injection, stop surface 140 will come into contact with an inside surface of the front housing 116 so that needle guard 110 cannot be further proximally displaced. The distance between the skin-contacting member and the stop surface 140 may be adjusted during manufacture to adjust the length X that the needle 106 extends from the housing 102

[0050] In one embodiment, legs 134 of needle guard 110 are configured to be received in openings of front housing 116. Further, legs 134 may include ridges 142 configured to engage grooves of front housing 1 16, not shown, to facilitate alignment and guiding of legs 134 as needle guard 1 10 is axially displaced. As shown in Fig. 6, legs 134 also include firing-initiation members, such as camming surfaces 144 at a proximal end of legs 134. In an embodiment, legs 134 and camming surface 144 may be concentrically symmetrical. Camming surfaces 144 are configured to engage and displace trigger mechanism 108 to initiate a firing of injection device 100. The proximate ends of legs 134 may also be sloped to facilitate legs 134 engaging trigger mechanism 108 when needle guard 110 is displaced from the extended position to the retracted position.

[0051] Needle guard 110 may extend from the front housing 116 a length Y. Length Y may be sufficient to cover needle 106 in the extended position. In some embodiments, the needle guard 110 may remain in the extended position when the cap 136 is coupled to the front housing 116. As shown in Figs. 4A-4B, the front housing 116 may include projections 146 extending from a distal end thereof, angled so as to allow the cap 136 to be rotationally tightened thereto In some embodiments, the cap 136 may be snap fit or friction fit to the front housing 116.

[0052] In some embodiments, the cap 136 may force the needle guard 110 from the extended position toward the retracted position into an intermediate position when the cap 136 is coupled to the front housing 116 without initiating a firing of the injection device 100. A needle shield (e.g., needle shield 243 in Fig. 14) coupled to the needle 106 may be configured to cover at least a portion of the needle 106. The needle shield may extend distally through an aperture of the cap 136 when the cap 136 is coupled to the housing. The intermediate position may reduce the length of the injection device 100, or may be necessary due to the needle 106 length requiring the needle guard 1 10 to be longer than the cap 136 can accommodate. The intermediate position may allow the injection device 100 to accommodate a variety of needles while maintaining the same footprint. The needle guard 110 may cover a portion of the needle 106 in the intermediate position. The needle guard 110 may partially expose the needle 106 within the cap 136 when the cap 136 is fixed to the front housing 116. This intermediate position may also be referred to as the storing position of the needle guard 110.

[0053] As shown in Figs. 15A-15B, the length Y may extend a first length Y1 in the extended position and may extend a second length Y2 in the intermediate position. The first length Y1 may be greater than the second length Y2. As shown in Fig. 15B, the length Y1 may be approximately 21 mm in the extended position. In some embodiments, the length Y1 is approximately 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, or 26 mm in the extended position In some embodiments, the length Y1 is between 15 mm - 26 mm, between 16 mm - 25 mm,between 17 mm - 24 mm, between 18 mm - 23 mm, between 19 mm - 22 mm, or between 20 mm - 21 mm in the extended position. As shown in Fig. 15 A, the length Y2 may be approximately 17 mm in the intermediate position. In some embodiments, the length Y2 is approximately 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, or 27 mm in the intermediate position. In some embodiments, the length Y2 is between 3 mm - 27 mm, between 4 mm - 26 mm, between 5 mm - 25 mm, between 6 mm - 24 mm, between 7 mm - 23 mm, between 8 mm - 22 mm, between 9 mm - 21 mm, between 10 mm - 20 mm, between 1 1 mm - 19 mm, between 12 mm - 18 mm, between 13 mm - 17 mm, or between 14 mm - 16 mm in the intermediate position. As shown in Fig. 15C, the length Y3 may be approximately 4 mm in the retracted position. In some embodiments, the length Y3 is approximately 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm or 5 mm in the retracted position. In some embodiments, the length Y3 is at least 0.1 mm, at least 0.2 mm, at least 0.3 mm, at least 0.4 mm, at least 0.5 mm, at least 1 mm, at least 2 mm, at least 3 mm, at least 4 mm or at least 5 mm in the retracted position In some embodiments, the length Y3 is between 0.1 - 5 mm, between 0.2 - 4 mm, between 0.3 - 3 mm, between 0.4 - 2 mm, or between 0.5 - 1 mm in the retracted position.

[0054] As shown in Figs. 11-12, the injection device 100 may be in a “locked-out” state when the needle guard 110 moves from the retracted position to the extended position following a firing. For example, the “locked-out” state can be observed after the user has removed injection device 100 from the injection site. In the retracted position, nothing is restraining needle guard 110 against the force of biasing member 112, and accordingly, needle guard 110 is distally displaced from the retracted position to the extended position under the force of biasing member 1 12, thereby covering needle 106. As needle guard 110 moves distally from the retracted position to the extended position under the force of biasing member 112, projections 146, which are flexed in a radially outward direction, engage the proximal surface of the front housing 116 and a proximal surface of opening 148 of the ram 122 to further prevent movement thereof. As shown in Fig. 11, the association of projections 146 with the proximal surface of opening 148 of the ram 122 prevents needle guard 110 from being displaced proximally, and the association of projections 146 with the proximal surface of the front housing 116 prevents needle guard 110 from being displaced distally. Thus, needle guard 110 is in a locked position, thereby locking-out injection device 100 such that needle 106 is covered and needle guard 110 is locked in place so that a user cannot attempt a subsequent injection. Afterwards, the user may affix cap 136 back onto the distal end of injection device 100.

[0055] Advantageously, in one embodiment, this “locked-out” state is not dependent on displacement of needle guard 110, but rather, is dependent on dispensing of the medicament stored in medicament container 104 and / or movement of ram 122 For example, injection device 100 becomes locked out in situations where the medicament is inadvertently dispensed, even if needle guard 110 has not been displaced. Injection device 100 may become locked out in any instance where energy source 120 is activated and ram 122 is distally displaced, causing ram rod 158 to displace plunger 130, thereby dispensing the medicament in the medicament container 104 through the needle 106.

[0056] As shown in Fig. 3, in one embodiment, a rear cap 118 includes a ram holding member 156. Ram holding member 156 may be a proj ection extending distally from a proximal surface of the rear cap 118. The ram holding member 156 may be configured to engage a trigger engagement member 154 of ram 122. For example, as shown in Fig. 3, in one embodiment, ram holding member 156 may be a bell-shaped projection, and may engage with a complementary shaped feature (e.g., trigger engagement member 154) of ram 122. In one embodiment, ram holding member 156 and the trigger engagement member 154 of ram 122 may include a circular cross-section

[0057] As shown in Fig. 7, ram 122 may be a generally cylindrical member. Ram 122 may include at least one opening extending therethrough to accommodate and receive features of the other components of the injection device 100. For example, ram 122 may include openings 148 at a distal end thereof, shaped and sized to receive the legs 134 of needle guard 110. Opening 148 may allow legs 134 of needle guard 110 to slide relative to the ram 122 when the needle guard 1 10 moves between the extended position to the retracted position. Although shown as a single piece, ram 122 may be a multiple-piece assembly that may be coupled together, for example, via a snap-fit connection, a press- fit connection, a threaded engagement, adhesives, welding, or other suitable couplings. Ram 122 may preferably include various features that may be configured to facilitate firing of injection device 100 to dispense the medicament stored in medicament container 104.

[0058] Ram 122 may further include openings 150 at a proximal end thereof, shaped and sized to receive the legs 152 of the trigger mechanism 108. Opening 150 may allow legs 152 of trigger mechanism 108 to slide relative to the ram 122 when the trigger mechanism 108 moves proximally when engaged by the needle guard 110 moving from the extended position to the retracted position.

[0059] As shown in Fig. 7, the ram 122 may include trigger engagement members 154 extending proximally therefrom. Although the trigger engagement member 154 is shown as projections, alternative implementations are contemplated such as an elongated tab, a thinned tab, a recess, a protrusion, a bulge, a thread, etc., that may engage a ram holding member 156 of the rear cap 1 18. As discussed above, ram holding member 156 may be a bulb extending distally from the rear cap 118within the housing 102 such that trigger engagement members 154 prevent the ram 122 from moving distally when engaged. In some embodiments, there may be one trigger engagement member 154, and in some embodiments, there may be more than one trigger engagement member 154 spaced circumferentially around the ram 122.

[0060] As shown in Figs. 2, 3 and 9-12, ram 122 may also include a ram rod 158 extending distally along the longitudinal axis LA from a proximal end thereof. Ram rod 158 may extend from a generally central portion of the proximal end of the ram 122. Ram rod 158 may extend beyond the length of the ram 122 into the medicament container 104 to engage the plunger 130. The plunger may include a receiver 160, shaped and sized to accommodate the distal end of the ram rod 158. The receiver 160 may ensure that the ram rod 158 engages a center portion of the plunger 130. In some embodiments, the ram rod 158 is coupled to the plunger 130. The ram rod 158 may move the plunger 130 relative to the medicament container 104 when the injection device 100 is fired.

[0061] As shown in Figs. 2-3, injection device 100, in certain embodiments, includes trigger mechanism 108 In one embodiment, ram 122 is slidably mounted within housing 102 and is engaged by energy source 120. Energy source 120 may engage a distal end of the ram 122 In an embodiment, energy source 120 includes a compression spring; however, other suitable energy sources may be used, such as an elastomer or compressed-gas spring, or a gas generator, or other suitable energy storage members In Figs. 2-3, ram 122 is in a pre-firing proximal -most position. During an injection, ram 122 is urged distally by energy released by energy source 120. Once an injection is completed, ram 122 is disposed in a distal-most position. In this distal position, needle guard 110 is locked out and extends over needle tip 106a so that a user cannot attempt a subsequent injection and the needle guard 1 10 may function as sharps protection.

[0062] While injection device 100 may deliver an injection of about 0.5 mL per injection, other volumes may be injected in alternative embodiments. In certain embodiments, injection device 100 may deliver an injection of about 1 ml per injection, about 1.5 ml per injection, about 2 ml per injection, about 2.5 ml per injection, about 3 ml per injection, or about 3.5 ml per injection. In certain embodiments, injection device 100 may deliver an injection of greater than 0.5 mL per injection, greater than 1 mL per injection, greater than 1.5 mL per injection, greater than 2 mL per injection, greater than 2.5 mL per inj ection, greater than 3 mL per inj ection, or greater than 3.5 mL per inj ection. In other embodiments, injection device 100 may deliver an injection in a range of about 0.2 mL to about 3 mL, in a range of about 0.5 mL to about 2.75 mL, in a range of about 0.75 mL to about 2.5 mL, in a range of about 1 mL to about 2.25 mL, in a range of about 1.25 mL to about 2 mL, or in a range of about 1 5 mL to about 1 75 mL

[0063] In one embodiment, injection device 100 may inject 0.5 ml of a medicament dissolved in an aqueous solution in about 0.1 sec., about 0.2 sec., about 0.3 sec., about 0.4 sec., about 0.5 sec., about 0.6 sec., about 0.7 sec., about 0.8 sec., about 0.9 sec , about 1 .0 sec., or any range determinable from the preceding times (for example, about 0.5 sec. to about 1.0 sec. or about 0.4 sec. to about 0.6 sec.). In one embodiment, injection device 100 may inject the medicament at a flow rate of at least2.5 mL / sec. The flow rate may be at least 3 mL / sec., at least 3.5 mL / sec., at least 4 mL / sec., at least4.5 mL / sec., at least 5 mL / sec., or at least 5.5 mL / sec. The flow rate may be between 2.5 mL / sec. to5.5 mL / sec., between 3 mL / sec. to 5 mL / sec., or between 3.5 mL / sec. to 4.5 mL / sec.

[0064] To initiate firing of the injection device 100, movement of the needle guard 110 from the extended position to the retracted position causes the trigger engagement member 154 to disengage from the ram 122, thereby allowing the energy source 120 to move the plunger 130 relative to the medicament container 104 to expel the medicament through the needle 106. As shown in Fig. 3, blocking portions 162 of trigger mechanism 108 may prevent trigger engagement member 154 of the ram 122 from moving axially when the needle guard 110 is in the extended position Blocking portions may have an interior position shaped to receive the trigger engagement member 154 to prevent rotation thereof relative to the trigger mechanism 108. During proximal movement of the needle guard 110 and distal movement of the trigger mechanism 108, the blocking portions 162 may move relative to the ram 122 and no longer engage trigger engagement member 154. When the blocking portions 162 no longer prevent radial movement of the trigger engagement member 154, the distal force produced by the energy source 120 on the ram 122 causes the trigger engagement member 154 to flex radially outward around the ram holding member 156. The ram 122 is thereby free to move relative to the housing 102 and causes the ram rod 158 to move the plunger 130 relative to the medicament container 104. As shown in Figs. 9-10, during a firing, the ram 122 forces the ram rod 158 to eject the volume of medicament contained in the medicament container 104.

[0065] As shown in Fig. 13, in one embodiment, injection device 100 includes a cap 136. The cap 136 may be removably affixable to a distal end of housing 102. In one embodiment, the cap 136 may be removably affixable to the distal end of front housing 116. For example, cap 136 may be removably affixed to the distal end of housing 102 via a threaded engagement, and rear cap 118 may include features (e.g., projections) configured to engage a portion of the proximal end of housing 102 (e.g., openings) to couple rear cap 118 to housing 102. The cap 136 may include a barrel 139 extending along the longitudinal axis LA shaped and sized to receive the needle 106 therein. The barrel 139 may extend at least partially along a length of the cap 136. A proximal end of the barrel 139 may be open to receive the needle 106 and / or a portion of the medicament container 104 A distalend of the barrel 139 may be closed to prevent the needle 106 from being exposed while the cap 136 is coupled to the housing 102. The barrel 139 may include an engagement lip 141 extending radially inward therefrom. The engagement lip 141 may extend around a circumference of the barrel 139 In one embodiment, the barrel 139 may include more than one engagement lip 141 spaced circumferentially apart. The engagement lip 141 may be configured to engage a needle shield 243 covering the needle 106, as shown in Fig. 14. In one embodiment, the distal end of the cap 136 may be open and shaped to allow the needle shield 243 to extend therethrough. Removal of the cap 136 may remove the needle shield 243 from the needle 106 to prepare for an injection.

[0066] When affixed to injection device 100, the cap 136 may ensure that an injection is not triggered by an inadvertent application of a force to needle guard 110. In one embodiment, the cap 136 includes two engagement features 138. As shown in Fig. 13, the cap 136 may include engagement features 138. Engagement features 138 may be threads configured to threadedly engage other features of injection device 100. For example, engagement feature 138 may be configured to secure cap 136 to the distal end of housing 102 or be configured to threadedly engage a distal portion of front housing 116. In one embodiment, engagement feature 138 may be configured to threadedly engage features (e.g., threads) of needle guard 110 to prevent proximal displacement of needle guard 1 10.

[0067] In another aspect of the present disclosure, a method of delivering a medicament to a subject is provided. The method may include providing an injector 100. The injector 100 may include a housing 102 having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis LA. The injector 100 may include a medicament container 104 disposed within the housing 102. The medicament container 104 may include the medicament. The injector 100 may include a needle 106 coupled to a distal end of the medicament container 104 and in fluid communication with the medicament container 104.

[0068] In some embodiments, the injector 100 may include a trigger mechanism 108. The trigger mechanism 108 may include a needle guard 110 retractably coupled to the distal end of the housing 102. The needle guard 110 may be movable along the longitudinal axis LA between an extended position, an intermediate position and a retracted position. In some embodiments, the method may include coupling a cap 136 to the housing 102, thereby moving the needle guard 110 proximally along the longitudinal axis LA from the extended position to the intermediate position.

[0069] In some embodiments, the method may include removing the cap 136 from the housing 102, thereby allowing a biasing member 112 disposed in the housing 102 to move the needle guard 110 distally along the longitudinal axis LA from the intermediate position to the extended position. The method may include pressing the needle guard 110 against an injection site of a user withsufficient force to move the needle guard 110 from the extended position to the retracted position. The method may include removing the injector 100 from the injection site, thereby allowing the biasing member 1 12 to move the needle guard 1 10 distally along the longitudinal axis from the retracted position to the extended position. In this distal position, needle guard 110 is locked-out and extends over needle tip 106a so that a user cannot attempt a subsequent injection and the needle guard 110 may function as sharps protection. The extended position may be the same as the locked-out position described above.

[0070] In some embodiments, the needle guard 110 extends from the housing 102 a first length in the extended position and a second length in the intermediate position. The first length may be greater than the second length. The first length may be approximately 21 mm. The second length may be approximately 17 mm.

[0071] Fig. 14 illustrates a second exemplary embodiment of an injection device, generally designated 200, having a pin-like safety mechanism 268. The injection device 200 may be an autoinjector, needle-free jet injector, needle-assisted jet injection device, powered injector, low-pressure auto-injector or other mechanized injector.

[0072] The injection device 200 includes a housing 202 having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis LA. The injection device 200 may further include various components and / or assemblies housed within housing 202. As shown in Fig. 14, these components may include a medicament container 204, a needle 206, and a trigger mechanism 208. Housing 202 may be a single piece component, or alternatively, housing 102 may be a multiple piece assembly coupled together, for example, via a snap-fit connection, a press-fit connection, a threaded engagement, adhesives, welding, or the like.

[0073] In one embodiment, the housing 202 includes a front sub-assembly and a rear subassembly coupled together, for example, via a snap-fit connection, a press-fit connection, a threaded engagement, adhesives, welding, or the like. The front sub-assembly may include a needle guard 210, a biasing member 212, a bushing 214, and a front housing 216. The rear sub-assembly may include a rear cap 218, an energy source 220, a ram 222, the trigger mechanism 208, and a rear housing 224. Providing two sub-assemblies may increase the ability to modulate components in each sub-assembly to allow customization and repeatability in manufacturing. A cap 236 may be releasably coupled to the front housing 216, and may receive a needle shield 243 therein.

[0074] In one embodiment, the pin-like safety mechanism 268 is used to keep a high-force spring compressed during assembly of the injection device 200. The pin-like safety mechanism 268 may limit the movement of internal components of the injection device 200 by compressing the energysource 220 to prevent premature or unintended actuation. Once the injection device 200 has been fully assembled, as shown in Fig. 14, the pin-like safety mechanism 268 can be removed without triggering the device. The pin-like safety mechanism 268 may be used during assembly of the rear sub-assembly, during transportation and handling, and during any other time prior to final assembly of the injection device 200.

[0075] The term “about” or “approximately” is used herein to provide literal support for the exact number that it precedes, as well as a number that is near to or approximately the number that the term precedes. In determining whether a number is near to or approximately a specifically recited number, the near or approximating unrecited number may be a number, which, in the context in which it is presented, provides the substantial equivalent of the specifically recited number. It should be appreciated that all numerical values and ranges disclosed herein are approximate values and ranges, whether “about” is used in conjunction therewith. It should also be appreciated that the term “about,” as used herein, in conjunction with a numeral refers to a value that may be ±0.01% (inclusive), ±0 1% (inclusive), ±0 5% (inclusive), ±1% (inclusive) of that numeral, ±2% (inclusive) of that numeral, ±3% (inclusive) of that numeral, ±5% (inclusive) of that numeral, ±10% (inclusive) of that numeral, or ±15% (inclusive) of that numeral. It should further be appreciated that when a numerical range is disclosed herein, any numerical value falling within the range is also specifically disclosed.

[0076] It will be appreciated by those skilled in the art that changes could be made to the exemplary embodiments shown and described above without departing from the broad inventive concepts thereof. It is to be understood that the embodiments and claims disclosed herein are not limited in their application to the details of construction and arrangement of the components set forth in the description and illustrated in the drawings. Rather, the description and the drawings provide examples of the embodiments envisioned. The embodiments and claims disclosed herein are further capable of other embodiments and of being practiced and carried out in various ways.

[0077] Specific features of the exemplary embodiments may or may not be part of the claimed invention, and various features of the disclosed embodiments may be combined. Unless specifically set forth herein, the terms “a”, “an” and “the” are not limited to one element but instead should be read as meaning “at least one”. Finally, unless specifically set forth herein, a disclosed or claimed method should not be limited to the performance of its steps in the order written, and one skilled in the art can readily appreciate that the steps may be performed in any practical order.

Claims

CLAIMSWhat is claimed is:

1. An injector, comprising: a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis; a medicament container disposed within the housing, the medicament container containing a medicament; a needle coupled to a proximal end of the medicament container and in fluid communication with the medicament container; a trigger mechanism comprising a needle guard retractably coupled to the proximal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position; and a cap removably coupled to the proximal end of the housing, wherein the needle guard is in the intermediate position when the cap is coupled to the proximal end of the housing.

2. The injector of claim 1, wherein the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position.

3. The injector of claim 2, wherein the first length is greater than the second length.

4. The injector of claim 3, wherein the first length is approximately 21 mm.

5. The injector of claim 3, wherein the second length is approximately 17 mm.

6. The injector of claim 1, wherein the needle guard is urged distally along the longitudinal axis from the extended position to the intermediate position when the cap is coupled to the housing.

7. The injector of claim 6, wherein the needle guard covers a portion of the needle in the intermediate position.

8. The injector of claim 6, wherein a needle shield coupled to the needle and configured to cover at least a portion of the needle extends distally through an aperture of the cap when the cap is coupled to the housing.

9. The injector of claim 8, wherein the needle shield is decoupled from the needle by the cap when the cap is decoupled from the housing.

10. The injector of claim 1, wherein the needle guard moves from the extended position to the retracted position in response to a user pressing the needle guard against an injection site.11 . The injector of claim 10, wherein the needle guard moves from the retracted position to the extended position when the user removes the injector from the injection site.12 The injector of claim 11, wherein the needle guard is moved from the retracted position to the extended position by a biasing member.

13. The injector of claim 11, wherein the needle guard is prevented from moving relative to the housing when moved from the retracted position to the extended position.

14. The injector of claim 1 further comprising: a biasing member, the biasing member configured to urge the needle guard distally along the longitudinal axis to the extended position when the cap is not coupled to the housing.

15. The injector of claim 14, wherein the needle guard covers a full length of the needle in the extended position.

16. The injector of claim 1, the trigger mechanism further comprising: a ram configured to move a plunger engageable with a distal end thereof relative to the medicament container; a trigger member configured to engage the ram and prevent movement thereof when the needle guard is in the extended position; andan energy source engaging a distal end of the ram, the energy source configured to move the ram distally relative to the housing.

17. The injector of claim 16, wherein movement of the needle guard from the extended position to the retracted position disengages the trigger member from the ram, thereby allowing the energy source to move the plunger relative to the medicament container to expel the medicament through the needle.

18. An injector, comprising: a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis; a medicament container disposed within the housing, the medicament container containing a medicament; a needle coupled to a distal end of the medicament container and in fluid communication with the medicament container; a trigger mechanism comprising a needle guard retractably coupled to the distal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position; and a cap removably coupled to the distal end of the housing, wherein the needle guard is in the intermediate position when the cap is coupled to the distal end of the housing, wherein the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position, wherein the first length is greater than the second length, and wherein the needle guard is urged distally along the longitudinal axis from the extended position to the intermediate position when the cap is coupled to the housing.

19. A method of delivering a medicament to a subject, the method comprising: providing an injector, the injector comprising: a housing having a proximal end and a distal end opposite the proximal end extending along a longitudinal axis;a medicament container disposed within the housing, the medicament container containing the medicament; a needle coupled to a distal end of the medicament container and in fluid communication with the medicament container; and a trigger mechanism comprising a needle guard retractably coupled to the distal end of the housing and movable along the longitudinal axis between an extended position, an intermediate position and a retracted position; coupling a cap to the housing thereby moving the needle guard distally along the longitudinal axis from the extended position to the intermediate position.

20. The method of claim 19, further comprising: removing the cap from the housing thereby allowing a biasing member disposed in the housing to move the needle guard distally along the longitudinal axis from the intermediate position to the extended position; pressing the needle guard against an injection site of the subject, thereby moving the needle guard from the extended position to the retracted position; removing the injector from the injection site, thereby allowing the biasing member to move the needle guard distally along the longitudinal axis from the retracted position to the extended position.

21. The method of claim 19, wherein the needle guard extends from the housing a first length in the extended position and a second length in the intermediate position, and wherein the first length is greater than the second length.

22. The method of claim 21, wherein the first length is approximately 21 mm and the second length is approximately 17 mm.

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