Patent Description:
Administering an injection is a process that presents a number of risks and challenges for users and healthcare professionals, both mental and physical. Injection devices typically fall into two categories - manual devices and autoinjectors. In a conventional manual device, manual force is required to drive a medicament through a needle. This is typically done by a plunger which is continuously pressed during the injection. There are numerous disadvantages associated with this approach. For example, if the plunger is released prematurely, the injection will stop and may not deliver an intended dose. Furthermore, the force required to push the plunger may be too high (e.g., if the user is elderly or a child). And, aligning the injection device, administering the injection, and keeping the injection device still during the injection may require dexterity which some patients may not have.

Autoinjector devices aim to make self-injection easier for patients. A conventional autoinjector may provide the force for administering the injection by a spring, and a trigger button or other mechanism may be used to activate the injection. Autoinjectors may be single-use or reusable devices.

<CIT> discloses an autoinjector comprising a housing in which can be mounted a syringe comprising a barrel for holding a volume of medicament, a needle at one end of the barrel in fluid communication with the medicament and a plunger axially-moveable in the barrel to a forwardmost position, the autoinjector further comprising a syringe support means for supporting the barrel at an axial location at or forward of the forwardmost position of the plunger and having a reaction surface for the syringe, whereby in use said reaction surface provides an axial compressive force on said barrel when a forward axial force is applied to the plunger.

There remains a need for an improved syringe carrier for an autoinjector, an improved autoinjector with such an improved syringe carrier and an improved method of assembling the autoinjector.

The present invention is directed to an autoinjector according to claim <NUM>, comprising a syringe carrier and a case adapted to receive the syringe carrier, wherein the syringe carrier comprises:.

The flexible arms return to the relaxed state due to a relative movement of the syringe carrier with respect to the syringe. This relative movement may be caused by an axial force on the syringe carrier.

According to an alternative aspect of the current disclosure, the two or more flexible arms extend straight in a relaxed state. Both embodiments - straight arms or inwardly directed arms - differ in the amount of tensional force in a pre-assembled state, i.e. during outward deflection of the flexible arms during engaging of the flexible arms onto the shaft of the syringe (= pre-stressed state of the flexible arms and pre-assembled state of the syringe within the syringe carrier). In particular, in the pre-stressed state of the arms, the tensional force of the straight arms is smaller than the tensional force of the inwardly directed arms.

The carrier design allows accurate support of the syringe on its datum despite large variations in syringe and needle shield dimensions and in the relative positioning of the needle shield and syringe. In particular, the syringe carrier, namely the inwardly protruded arms, allows a large syringe datum providing a robust support surface with high safety margin. Furthermore, the final assembling is simplified and allows an axial assembly process.

In an exemplary embodiment, the flexible arms extend distally from a carrier front end. In a further exemplary embodiment, the flexible arms are symmetrically arranged around the carrier front end. The flexible arms are radially outwards deflectable and pre-stressed in the pre-assembled position.

In an exemplary embodiment, the flexible arms comprise protrusions inwardly directed onto the syringe and configured to couple with a distal shoulder of the syringe. Preferably, the syringe is a pre-filled syringe having a needle. Alternatively, a medicament container having a needle may be provided.

According to a further embodiment, an outer diameter of the protrusions is smaller than an outer diameter of the protective needle sheath and an outer diameter of a shaft of the syringe. The smaller outer diameter of the protrusions supports and thus prepositions the syringe at an axial position with respect to the syringe carrier and the protective needle sheath.

In an exemplary embodiment, the housing includes a proximal aperture having an outer diameter, in part, smaller than an outer diameter of a proximal syringe flange. When moving the syringe within the syringe carrier, the proximal syringe flange engages and rests onto a carrier rear end of the proximal aperture. Preferably, the proximal aperture has an elliptical or oval form and thus the outer diameter of the proximal aperture may be smaller as well as larger than the circular outer diameter of the proximal syringe flange.

According to another aspect of the current disclosure, there is provided an autoinjector comprising at least a syringe carrier and a case adapted to receive the syringe carrier, wherein the syringe carrier is releasably holdable in the case.

The case is adapted to restrain and support inward deflection of the flexible arms in the mounted position and thus in the relaxed state of the flexible arms when the axial force operates onto the syringe The case comprises at least one inwardly directed edge operating onto the flexible arms wherein the inward deflection of the flexible arms in the mounted position forces the syringe and the protective needle sheath apart when the axial force operates onto the syringe carrier. The design of the syringe carrier and the case are such that a protective needle sheath, e.g. a rigid or a rubber needle sheath, is automatically displaced to a predetermined position during assembly to provide sufficient clearance to support the syringe at the datum.

The case comprises at least one inwardly directed rigid edge, e.g. circumferential-ridged edge or latches, at a distal end in the direction of the protective needle sheath.

In an exemplary embodiment, the syringe carrier comprises holding clamps on an axial carrier rear end, e.g. opposite to the direction of the protective needle sheath for releasable holding of the syringe carrier in the case. The holding clamps are integrally formed with the syringe carrier, e.g. as tongues. In particular, the holding clamps are outwardly directed. Furthermore, the syringe carrier comprises at least two clamps arranged opposite to each other on a carrier rear end, e.g. on a carrier flange or carrier head.

In an exemplary embodiment, the case comprises at least one inner support to releasably hold the holding clamps. In particular, the inner support may be formed as an inner groove or slot or opening.

In an exemplary embodiment, the case comprises a front case and a rear case.

The front case may be adapted to releasably hold the carrier at its rear end and to fixedly hold the carrier at its front end. Furthermore, the front case is adapted to enclose the autoinjector and to restrain and support the inward deflection of the flexible arms of the carrier in the mounted position.

Furthermore, the rear case is adapted to prevent axial movement of the syringe relative to the case and to close an axial case end opposite to the direction of the protective needle sheath.

In an exemplary embodiment, the autoinjector further comprises a needle shroud telescopically coupled to the case and movable between an extended position relative to the case in which the needle is covered and a retracted position relative to the case in which the needle is exposed, a shroud spring biasing the needle shroud in a distal direction relative to the case, a plunger slidably disposed in the case, and a drive spring to drive the plunger.

In an exemplary embodiment, the case comprises the front case and the rear case which is surrounded by the front case along a longitudinal direction and adapted to close an open proximal end of the front case.

In an exemplary embodiment, the needle shroud includes an inner shroud boss on which an inner case boss of the case abuts.

In an exemplary embodiment, due to an axial force applied to the rear end of the syringe carrier, the holding clamps are released from the case so that the syringe carrier together with the assembled syringe may be moved within the case.

In an exemplary embodiment, the case comprises one or more openings or one or more apertures to allow insertion of at least one assembling tool for applying a force to move the syringe carrier within the case wherein the at least one holding clamp of the syringe carrier from the case is released or to move at least the syringe within the syringe carrier.

The invention is also directed to a method of assembling an autoinjector according to independent claim <NUM>.

The inward deflection of the flexible arms in the mounted and final position displaces the protective needle sheath to allow space to support the syringe at its datum. In this mounted position, the flexible arms of the syringe carrier are held rigidly by the case and thus safely support the syringe.

The flexible arms return to the relaxed state due, in part, to an axial force operating on the syringe carrier, so that the syringe carrier is relatively moved with respect to the case and, finally, in addition with respect to the syringe.

In an exemplary embodiment, for inserting the syringe into the syringe carrier, the syringe is moved into an opened carrier rear end axially forwards until a syringe flange engages the carrier rear end.

When inserting the syringe into the syringe carrier, for example, a back-assembling tool is pushed onto the syringe axially forwards. Furthermore, when the syringe is inserted into the syringe carrier, the flexible arms engage a shaft of the syringe and outwardly deflect and thus are pre-stressed.

For an optional pre-positioning of the syringe within the syringe carrier, the syringe is moved within the fixed carrier axially rearwards until the flexible arms are deflected and snapped back radially inwards and thus relaxed to couple with a distal shoulder of the syringe. When, optionally, pre-positioning the syringe within the syringe carrier, a front-assembling tool is pushed onto the syringe axially rearwards. In particular, the front-assembling tool is pushed onto the protective needle sheath axially rearwards so that the protective needle sheath axially moves together with the syringe in the rearward direction.

In an exemplary embodiment, for releasing the syringe carrier from the case and moving the syringe carrier forwards within in the case, for example, a back-assembling tool is pushed onto the syringe carrier axially forwards so that the carrier moves together with the syringe in a forward direction.

For finally mounting and positioning of the syringe within the syringe carrier, when moving the syringe carrier forwards within the case and reaching the mounted position, the syringe carrier with the syringe is moved forwards until the protective needle sheath of the syringe engages a barb within the cap so that the syringe is fixed and the syringe carrier is further relatively moved with respect to the syringe until the flexible arms move over the distal end of the syringe and return to the relaxed state when reaching the final mounted position. In this final mounted position, the flexible arms engage and displace the protective needle sheath to allow space to support the syringe in its final position and at its datum. Further, in this final mounted position, the case is adapted to restrain and support the inward deflection of the flexible arms forcing the syringe and the protective needle sheath apart.

According to a further aspect of the current disclosure, a method of assembling an autoinjector is provided and comprises the steps of:.

The case is adapted to restrain the inward deflection of the flexible arms when the syringe carrier reaches the mounted position such that, due to an axial force acting onto the syringe carrier, the case operates onto the flexible arms forcing the syringe and the protective needle sheath apart. The flexible arms engage behind the rear end of the protective needle sheath. The protective needle sheath and the syringe are spaced apart until the flexible arms are restrained and forced radially inwards by the case. At his point, the syringe carrier and the protective needle sheath move as one while the syringe is "left behind" until the flexible arms of the syringe carrier are fully engaged. Optionally, the syringe may be pre-assembled and positioned within the syringe carrier by moving the protective needle sheath rearwards so that the protective needle sheath together with the syringe moves in the rearward direction with respect to the fixed syringe carrier until the flexible arms are inwardly deflected and return to its relaxed state and engage the protective needle sheath.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description.

The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:.

<FIG> is a simplified longitudinal section of an exemplary embodiment of an autoinjector <NUM> according to the present invention after assembly and shows the main assembling parts. <FIG> is a schematic perspective partly cut-away view of the autoinjector <NUM>. <FIG> shows an explosion view of all components of the autoinjector <NUM>. <FIG>, <FIG> show the assembled autoinjector <NUM> in more detail.

The autoinjector <NUM> comprises a case <NUM>. The case <NUM> is designed as a multi-part. In particular, the case <NUM> comprises a front case <NUM> and a rear case <NUM>. The rear case <NUM> is surrounded by the front case <NUM> along a longitudinal direction and adapted to close an open proximal end of the front case <NUM>. The case <NUM> is adapted to hold a syringe <NUM>.

The syringe <NUM> may be a pre-filled syringe or a pre-filled medicament container and has a needle <NUM> arranged at a distal end. The syringe <NUM> may be pre-assembled. Typically, a protective needle sheath <NUM> may be removably coupled to the needle <NUM>. The protective needle sheath <NUM> may be a rubber needle sheath or a rigid needle sheath (which is composed of rubber and a full or partial plastic shell).

A stopper <NUM> is arranged for sealing the syringe <NUM> proximally and for displacing a medicament M contained in the syringe <NUM> through the needle <NUM>. In other exemplary embodiments, the syringe may be a cartridge or a container which includes the medicament M and engages a removable needle (e.g., by threads, snaps, friction, etc.).

In an exemplary embodiment, a cap <NUM> may be removably disposed at a distal end of the case <NUM>. The cap <NUM> may include a grip element <NUM> (e.g., a barb, a hook, a narrowed section, etc.) arranged to engage the protective needle sheath <NUM>, the cap <NUM> and/or a needle shroud <NUM> telescoped within the case <NUM>. The cap <NUM> may comprise grip features <NUM> for facilitating removal of the cap <NUM> (e.g., by twisting and/or pulling the cap <NUM> relative to the case <NUM>).

Furthermore, the cap <NUM> comprises a barb as the grip element <NUM> grasping the protective needle sheath <NUM> in a final mounted position of the syringe <NUM> within the case <NUM>.

In an exemplary embodiment, a shroud spring <NUM> (shown in <FIG> and <FIG>) is arranged to bias the needle shroud <NUM> in a distal direction D against the case <NUM>.

In an exemplary embodiment, a drive spring <NUM> is arranged within the case <NUM>. A plunger <NUM> serves for forwarding a force of the drive spring <NUM> to the stopper <NUM>. In an exemplary embodiment, the plunger <NUM> is hollow and the drive spring <NUM> is arranged within the plunger <NUM> biasing the plunger <NUM> in the distal direction D against the case <NUM>. In another exemplary embodiment, the plunger <NUM> may be solid and the drive spring <NUM> may engage a proximal end of the plunger <NUM>. Likewise, the drive spring <NUM> could be wrapped around the outer diameter of the plunger <NUM> and extend within the syringe <NUM>.

In an exemplary embodiment, a plunger release mechanism <NUM> is arranged for preventing release of the plunger <NUM> prior to retraction of the needle shroud <NUM> relative to the case <NUM> and for releasing the plunger <NUM> once the needle shroud <NUM> is sufficiently retracted.

In an exemplary embodiment, a shroud lock mechanism <NUM> is arranged to prevent retraction of the needle shroud <NUM> relative to the case <NUM> when the cap <NUM> is in place, thereby avoiding unintentional activation of the autoinjector <NUM> (e.g., if dropped, during shipping or packaging, etc.).

The shroud lock mechanism <NUM> may comprise one or more compliant beams <NUM> on the cap <NUM> and a respective number of apertures <NUM> (shown in <FIG>) in the needle shroud <NUM> adapted to receive each of the compliant beams <NUM>. When the cap <NUM> is attached to the autoinjector <NUM>, the compliant beams <NUM> abut a radial stop <NUM> on the case <NUM> which prevents the compliant beams <NUM> from disengaging the apertures <NUM>.

When the cap <NUM> is attached to the autoinjector <NUM>, axial movement of the cap <NUM> in the proximal direction P relative the case <NUM> is limited by a rib <NUM> on the cap <NUM> abutting the case <NUM>. When the cap <NUM> is pulled in the distal direction D relative to the case <NUM>, the compliant beams <NUM> may abut an edge of the aperture <NUM> and deflect to disengage the aperture <NUM>, allowing for removal of the cap <NUM> and the protective needle sheath <NUM> attached thereto. Further, the grip element <NUM> of the cap <NUM> grasps the protective needle sheath <NUM> and allows removal of the protective needle sheath <NUM>, too.

In the shown embodiment, the cap <NUM> is closed at its distal end. Alternatively, the cap may comprise a closable opening for inserting a front assembling tool (an example is shown in <FIG>).

In an exemplary embodiment, the compliant beams <NUM> and/or the apertures <NUM> may be ramped to reduce force necessary to disengage the compliant beams <NUM> from the apertures <NUM>.

The autoinjector <NUM> comprises at least an audible indicator <NUM> (shown in <FIG>) for producing an audible feedback of completion of medicament M delivery. The audible indicator <NUM> is formed for example as a bistable spring and is held in the rear case <NUM>.

The rear case <NUM> is adapted to prevent axial movement of the syringe <NUM> after assembling, in particular during storage, transportation and normal use. In detail, the rear case <NUM> comprises at its front end resilient arms <NUM>. The resilient arms <NUM> are formed as labyrinth arms to damp impact forces.

To allow an accurate support of the syringe <NUM> during and after assembling, the autoinjector <NUM> comprises a syringe carrier <NUM>. The syringe carrier <NUM> is adapted to assemble and hold the syringe <NUM> within the case <NUM> and is further explained in more detail.

In particular, the syringe <NUM> is a <NUM> pre-filled syringe with a rigid protective needle sheath <NUM>. Usually, the syringe <NUM> and the protective needle sheath <NUM> have large variations in dimensions. To allow accurate support of the syringe <NUM> in a mounted position despite these large variations, the design of the syringe carrier <NUM> and the front case <NUM> are adapted to automatically displace and position the protective needle sheath <NUM> to a predetermined position during assembly to provide sufficient clearance to support the syringe <NUM> at its datum in the mounted position.

Therefore, the syringe carrier <NUM> comprises flexible arms <NUM> adapted to mount and position the syringe <NUM> and hold it in a mounted position. The flexible arms <NUM> are protruded inwards in a relaxed state.

The syringe carrier <NUM> comprises a housing <NUM> adapted to receive the syringe <NUM> and at least two flexible arms <NUM> adapted to couple with the syringe <NUM> in the mounted position. The housing <NUM> is formed as a hollow cylinder.

The flexible arms <NUM> are distally extended from an axial carrier front end <NUM> of the housing <NUM> and are protruded inwards in a relaxed state, e.g. are inwardly formed, e.g. angled. The flexible arms <NUM> comprise at its distal ends protrusions <NUM> inwardly directed.

To support the final assembling of the syringe <NUM> into the syringe carrier <NUM>, the at least two flexible arms <NUM> are adapted to couple with the syringe <NUM> in the mounted position in such a manner that the outwardly pre-stressed flexible arms <NUM> return back or snap back radially inwards into the relaxed state in the mounted position. The flexible arms <NUM> return back into the relaxed state due to a relative movement of the syringe carrier with respect to the syringe. This relative movement may be caused by an axial force operating on the syringe carrier <NUM>, e.g. on a carrier rear end <NUM>.

Furthermore, the front case <NUM> is adapted to restrain the inward deflection of the flexible arms <NUM> when the syringe <NUM> is in the mounted position such that an assembled force of the case <NUM> operates onto the flexible arms <NUM>, forcing the syringe <NUM> and the protective needle sheath <NUM> apart so that the syringe <NUM> is secured in the mounted position shown in <FIG> and <FIG>.

The carrier <NUM> comprises a carrier rear end <NUM> opposite to the carrier front end <NUM>. At the carrier rear end <NUM>, the carrier <NUM> comprises a carrier flange <NUM> with holding clamps <NUM> for releasable intermittent holding of the carrier <NUM> relative to the case <NUM>.

The holding clamps <NUM> are integrally formed on the carrier flange <NUM> as tongues. Proximal ends of the holding clamps <NUM> are outwardly directed to engage slots <NUM>. <NUM> of the case <NUM>. In an embodiment, the carrier <NUM> comprises two holding clamps <NUM> arranged opposite to each other. Instead of slots <NUM>. <NUM>, the front case <NUM> may comprise an inner support to releasably hold the holding clamps <NUM>. In particular, the inner support may be formed as an inner groove.

In an exemplary embodiment, the autoinjector <NUM> may be formed from at least two subassemblies, e.g., a control or front subassembly <NUM> and a drive or rear subassembly <NUM>, to allow for flexibility as to the time and location of manufacture of the subassemblies <NUM>, <NUM> and final assembly with the syringe <NUM>.

<FIG> show a perspective view of an exemplary embodiment of a back-assembling tool <NUM> having rigid arms <NUM> and of an optional front-assembling tool <NUM>.

If the autoinjector <NUM> comprises a cap <NUM> with a closed distal end, the syringe <NUM> is only assembled within the case <NUM> and the syringe carrier <NUM> by the back-assembling tool <NUM>.

Optionally, if the cap <NUM> comprises a closable opening, a front-assembling tool <NUM> having rigid arms <NUM> may be provided to pre-position the syringe <NUM> into a final position within the syringe carrier <NUM>.

<FIG> is a perspective exploded view of an exemplary embodiment of a front subassembly <NUM> of an autoinjector <NUM>.

In an exemplary embodiment, the front subassembly <NUM> comprises at least the front case <NUM>, the needle shroud <NUM> and the syringe carrier <NUM> into which the syringe <NUM> is to be assembled.

The needle shroud <NUM> and the syringe carrier <NUM> are mounted into the front case <NUM>. In particular, the syringe carrier <NUM> is stable due to clamp connection of the holding clamps <NUM> within slots <NUM>. <NUM> of the front case <NUM> at its rear end.

For assembling the syringe <NUM> into the syringe carrier <NUM> and thus into the front case <NUM>, the case <NUM> comprises one or more apertures to allow insertion of the assembling tool <NUM> for applying a force onto the syringe <NUM> to insert it within the syringe carrier <NUM> and further for applying a force onto the syringe carrier <NUM> to release the at least one holding clamp <NUM> of the syringe carrier <NUM> from the case <NUM> and to move the syringe carrier <NUM> together with the syringe <NUM> with respect to the case <NUM>.

As shown in <FIG>, the case <NUM>, in particular the front case <NUM> is provided in which the syringe carrier <NUM> is pre-assembled and mounted. The syringe <NUM> with the needle <NUM> encapsulated by the removable protective needle sheath <NUM> is inserted and pre-positioned axially into the syringe carrier <NUM> as described in more detail below.

To assemble the front subassembly <NUM>, the syringe carrier <NUM> is axially inserted into the front case <NUM> from a proximal end P until holding clamps <NUM> of the syringe carrier <NUM> engage retaining slots <NUM>. <NUM> in the front case <NUM>, so that the syringe carrier <NUM> is fixed and stable in the front case <NUM>.

Additionally, the shroud spring <NUM> is inserted into the needle shroud <NUM> (shown in <FIG>, not shown in <FIG>) and the needle shroud <NUM> with the shroud spring <NUM> is inserted into a distal end <NUM>. <NUM> of the front case <NUM>. The cap <NUM> together with the barb (grip element <NUM>) is arranged over the distal end of the needle shroud <NUM>.

After the syringe carrier <NUM> is fixed in the front case <NUM>, the syringe <NUM> may be inserted into the front subassembly <NUM>, namely into the syringe carrier <NUM> from its carrier rear end <NUM> as described above.

For inserting the syringe <NUM> into the syringe carrier <NUM>, the syringe <NUM> is moved into the opened carrier rear end <NUM> axially forwards until the syringe flange <NUM> engages the carrier rear end <NUM> as it is shown by arrow F1 in <FIG>. When inserting the syringe <NUM> into the syringe carrier <NUM>, e.g. the back-assembling tool <NUM> is pushed onto the syringe <NUM> axially forwards.

When the syringe <NUM> is inserted into the syringe carrier <NUM>, the flexible arms <NUM> engage a shaft of the syringe <NUM> and outwardly deflect and thus are pre-stressed (shown in <FIG>).

<FIG> shows in detail the front subassembly <NUM> with the mounted syringe carrier <NUM> together with the mounted syringe <NUM> in an intermediate assembling position.

As the protective needle sheath <NUM> is usually larger than the syringe diameter, the syringe <NUM> cannot be assembled into the front case <NUM> through the needle shroud <NUM>. To overcome this problem, the syringe carrier <NUM> is provided. Hence the housing <NUM> of the syringe carrier <NUM> comprises an inner diameter larger than the outer diameter of a shaft of the syringe <NUM>. Furthermore, the housing <NUM> includes a proximal aperture having an outer diameter, in part, smaller than an outer diameter of the proximal syringe flange <NUM>.

The syringe <NUM> is inserted and moved into the opened carrier rear end <NUM> of the syringe carrier <NUM> axially forwards until the syringe flange <NUM> engages the carrier rear end <NUM>, in particular a proximal shoulder <NUM>. <NUM> of the carrier flange <NUM>. Alternatively, the syringe flange <NUM> engages a distal shoulder of the carrier flange <NUM>.

In this corresponding intermediate assembling position of the front subassembly <NUM> with the assembled syringe carrier <NUM> and the syringe <NUM>, the holding clamps <NUM> are held in the slots <NUM>. <NUM> and the flexible arms <NUM> of the syringe carrier <NUM> sit on the barrel or shaft of the syringe <NUM> and outwardly deflect and thus are pre-stressed.

As it is shown in <FIG> and <FIG>, afterwards, for final positioning the syringe <NUM> within the syringe carrier <NUM>, an axial force according to arrow F2 is then applied to the syringe carrier <NUM> so that the holding clamps <NUM> are released from the slots <NUM>. <NUM> and the syringe carrier <NUM> together with the syringe <NUM> are moved within the case <NUM> into the distal direction D. The axial force F2 applied to the syringe carrier <NUM> is smaller than a holding force, e.g. friction force, between the syringe carrier <NUM> and the syringe <NUM>, e.g. between their contacting surfaces. Furthermore, the axial force F2 is greater than the retention force of the holding clamps <NUM> on the front case <NUM>.

As it is shown in <FIG> and <FIG>, for example, the back-assembling tool <NUM> is pushed onto the syringe carrier <NUM> axially forwards so that the syringe carrier <NUM> is released from the case <NUM> and moves together with the syringe <NUM> in a forward direction. As best seen in <FIG>, the arms <NUM> of the back-assembling tool <NUM> are attached to the syringe carrier <NUM>. The carrier rear end <NUM> comprises an elliptical or oval form and has an outer diameter, in part, larger than the outer diameter of the syringe flange <NUM>.

Due to the axial force according to the arrow F2 acting on the syringe carrier <NUM>, the holding clamps <NUM> are released from the slots <NUM>. <NUM> so that the carrier <NUM> together with the syringe <NUM> is moved forwardly.

When acting an axial force F2 on the syringe carrier <NUM>, the syringe carrier <NUM> with the syringe <NUM> is moved forwards within the case <NUM> and reaching the mounted position until the protective needle sheath <NUM> of the syringe <NUM> engages the barb (grip element <NUM>) within the cap <NUM> so that the syringe <NUM> is stopped and fixed and the syringe carrier <NUM> is further relatively moved with respect to the syringe <NUM> within the case <NUM> until the flexible arms <NUM> move over the distal end of the syringe <NUM> and return to the relaxed state when reaching the final mounted position. In this final mounted position, the flexible arms <NUM> engage and displace the protective needle sheath <NUM> to allow space to support the syringe <NUM> in its final position and at its datum. Furthermore, in this final mounted position, the case <NUM> is adapted to restrain and support the inward deflection of the flexible arms <NUM> forcing the syringe <NUM> and the protective needle sheath <NUM> apart.

In particular, the barb <NUM> comprises for example extended arms (not further shown) attached to a shoulder of the protective needle sheath <NUM> when the protective needle sheath <NUM> is axially moved within the cap <NUM> during forward movement of the syringe carrier <NUM> and the syringe <NUM> within the case <NUM> so that a further movement of the syringe <NUM> is stopped. Due to further axial force F2 on the syringe carrier <NUM> and the attachment of the fixed barb <NUM> onto the protective needle sheath <NUM>, the syringe carrier <NUM> is relatively moved with respect to the syringe <NUM> axially forwards until the flexible arms <NUM> are deflected radially inwards to couple the distal shoulder of the syringe <NUM>.

Furthermore, the front case <NUM> is adapted to further inwardly deflect the flexible arms <NUM> of the syringe carrier <NUM> according to arrow F3 so that the syringe <NUM> and the protective needle sheath <NUM> are forced apart according to arrow F3 when the syringe <NUM> reaches its mounted position shown in <FIG> and <FIG>.

In particular, the front case <NUM> comprises an edge <NUM>. The edge <NUM>. <NUM> is inwardly directed and is formed as an inner circumferential rigid edge.

During assembling and providing the axial force F2 onto the syringe carrier <NUM>, the flexible arms <NUM> are returned back in the relaxed state and further inwardly deflected and restrained in the relaxed state by the edge <NUM>. <NUM> according to arrow F3 so that the protective needle sheath <NUM> is displaced according to arrows F4 to allow space between the syringe <NUM> and the protective needle sheath <NUM> to support and finally position the syringe <NUM> in its mounted position.

As shown in <FIG>, in the final mounted position, the flexible arms <NUM> of the syringe carrier <NUM> are rigidly held and stable by the edge <NUM>. <NUM> of the front case <NUM> to safely support and position the syringe <NUM>.

<FIG> shows the syringe carrier <NUM> in more detail. The syringe carrier <NUM> additionally comprises support elements <NUM> to align and position the syringe <NUM> and the syringe carrier <NUM> with respect to the front case <NUM>. The support elements <NUM> are formed as axial ribs symmetrically arranged on the syringe carrier <NUM>. The ribs are extended from the proximal end of the carrier flange <NUM> along the longitudinal axis. The ribs may be shaped as a "T" or "I".

The length of the syringe carrier <NUM> may be smaller than the length of the syringe <NUM> to be assembled.

<FIG> show the carrier front end <NUM> in more detail. The flexible arms <NUM> are deflected and protruded radially inwards in a relaxed position. To finally position the syringe <NUM> with respect to the protective needle sheath <NUM>, the inner diameter of the protrusions <NUM> is smaller than an outer diameter of the protective needle sheath <NUM> and an outer diameter of a shaft of the syringe <NUM>.

In summary, <FIG> shows a longitudinal section of the autoinjector <NUM> according to the present invention after final assembly, wherein the rear subassembly <NUM> (also called drive subassembly) is mounted onto the front subassembly <NUM>.

In an exemplary embodiment, the rear subassembly <NUM> comprises the plunger <NUM>, the drive spring <NUM> and the rear case <NUM>. Those of skill in the art will understand that if the viscosity or volume, for example, of the medicament M in the syringe <NUM> is changed, only parts of the rear subassembly <NUM> may need to be changed. To assemble the rear subassembly <NUM>, the drive spring <NUM> is inserted into the plunger <NUM> and the plunger <NUM> is inserted in the rear case <NUM> in the proximal direction P, thereby compressing the drive spring <NUM>. Once the plunger <NUM> and the drive spring <NUM> reach a compressed position, it is rotated by an angle, e.g. approximately <NUM>° relative to the rear case <NUM>, to engage the plunger <NUM> to the rear case <NUM>. In an exemplary embodiment, the rear case <NUM> may have a cam surface to engage the plunger <NUM> to induce this rotation prior to the plunger <NUM> and the drive spring <NUM> reaching the compressed position.

In an exemplary embodiment, after the final assembly of the rear subassembly <NUM> to the front subassembly <NUM>, the autoinjector <NUM> may be kept in temperature controlled environment (e.g., cold chain storage) to, for example, reduce creep in highly stressed components, e.g. under load from the drive spring <NUM>.

In an exemplary embodiment, a force required to press the needle shroud <NUM> may be approximately <NUM> N to <NUM> N. Likewise, the mechanism may work with a higher force.

In an exemplary embodiment, the syringe <NUM> used in the autoinjector <NUM> may be a syringe capable of containing approximately <NUM> of the medicament M. In another exemplary embodiment, the syringe <NUM> used in the autoinjector <NUM> may be a syringe capable of containing approximately <NUM> of the medicament M.

The autoinjector <NUM> according to the present invention may have an increased shelf-life compared to conventional autoinjectors, because, for example, only the plunger <NUM> is subjected to the relatively high force of the drive spring <NUM>.

The autoinjector <NUM> according to the present invention may be used as a platform as the drive spring <NUM> can be changed to alter a force applied to the plunger <NUM>, e.g. for delivering medicaments with different viscosities drugs or reconstituted medicaments, or changing a time required to inject a dose of the medicament.

The cap <NUM> is suitable for being applied with any kind of injection device or autoinjector.

<FIG> and <FIG> show an option for an assembling method of the front subassembly <NUM>. In this embodiment, the cap <NUM> comprises an opening through which a front-assembling tool <NUM> may be inserted for pre-positioning the syringe <NUM> within the syringe carrier <NUM>.

For pre-positioning the syringe <NUM> within the syringe carrier <NUM>, an axial force according to arrow F5 is applied to the syringe <NUM> from the distal end D. In particular, an axial force is applied to the protective needle sheath <NUM> of the syringe <NUM>. As the syringe carrier <NUM> is fixed in the case <NUM>, the protective needle sheath <NUM> together with the syringe <NUM> is moved backwards relative to the carrier <NUM> until the flexible arms <NUM>, in particular the protrusions <NUM> of the carrier <NUM>, are inwardly deflected and couple with the distal shoulder of the syringe <NUM> and come into contact with the protective needle sheath <NUM> as it is shown in <FIG>.

The axial forces according to arrow F1 - for syringe insertion - can be provided by the back-assembling tool <NUM>.

The axial force according to arrow F5 for pre-positioning the syringe <NUM> within the syringe carrier <NUM> is opposite to the axial force of arrow F1 for syringe insertion and can be applied as a separate assembly step, e.g. by pushing the front-assembling tool <NUM> onto the protective needle sheath <NUM> as it is shown in <FIG>.

The front-assembling tool <NUM> comprises extended arms <NUM> attached to a shoulder of the protective needle sheath <NUM> when the front-assembling tool <NUM> is pushed onto the protective needle sheath <NUM> axially rearwards so that the syringe <NUM> is moved within the fixed syringe carrier <NUM> axially rearwards, too, until the flexible arms <NUM> are deflected radially inwards to couple with the distal shoulder of the syringe <NUM>.

For final positioning of the syringe <NUM> within the syringe carrier <NUM>, the syringe carrier <NUM> is released from the case <NUM> and moves forwards within in the case <NUM> due to the axial force F2 shown in <FIG> and as described above for the other embodiment in more detail.

<FIG> shows an alternative embodiment for a syringe carrier <NUM>. According to this alternative embodiment, the two or more flexible arms <NUM> extend straightly in the relaxed state.

The assembling method is the same for this syringe carrier <NUM> with straight extended flexible arms <NUM>. The straight extended flexible arms <NUM> differ in a different, in particular smaller amount of tensional force in their pre-stressed state, i.e. during outward deflection when the flexible arms <NUM> engage the shaft of the syringe <NUM> in the pre-assembled state of the syringe <NUM> within the syringe carrier <NUM> (see <FIG>).

Without limitation, a drug delivery device may be an injection device (e.g., syringe, pen injector, auto injector, large-volume device, pump, perfusion system, or other device configured for intraocular, subcutaneous, intramuscular, or intravascular delivery), skin patch (e.g., osmotic, chemical, micro-needle), inhaler (e.g., nasal or pulmonary), implantable (e.g., coated stent, capsule), or feeding systems for the gastro-intestinal tract.

Exemplary insulin derivatives are, for example, B29-N-myristoyl-des(B30) human insulin; B29-N-palmitoyl-des(B30) human insulin; B29-N-myristoyl human insulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29 human insulin; B28-N-palmitoyl-LysB28ProB29 human insulin; B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N-palmitoyl- ThrB29LysB30 human insulin; B29-N-(N-palmitoyl-gamma-glutamyl)-des(B30) human insulin; B29-N-(N-lithocholyl-gamma-glutamyl)-des(B30) human insulin; B29-N-(ω-carboxyheptadecanoyl)-des(B30) human insulin and B29-N-(ω-carboxyheptadecanoyl) human insulin. Exemplary GLP-<NUM>, GLP-<NUM> analogues and GLP-<NUM> receptor agonists are, for example: Lixisenatide / AVE0010 / ZP10 / Lyxumia, Exenatide / Exendin-<NUM> / Byetta / Bydureon / ITCA <NUM> / AC-<NUM> (a <NUM> amino acid peptide which is produced by the salivary glands of the Gila monster), Liraglutide / Victoza, Semaglutide, Taspoglutide, Syncria / Albiglutide, Dulaglutide, rExendin-<NUM>, CJC-<NUM>-PC, PB-<NUM>, TTP-<NUM>, Langlenatide / HM-11260C, CM-<NUM>, GLP-<NUM> Eligen, ORMD-<NUM>, NN-<NUM>, NN-<NUM>, NN-<NUM>, Nodexen, Viador-GLP-<NUM>, CVX-<NUM>, ZYOG-<NUM>, ZYD-<NUM>, GSK-<NUM>, DA-<NUM>, MAR-<NUM>, MAR709, ZP-<NUM>, ZP-<NUM>, TT-<NUM>, BHM-<NUM>. MOD-<NUM>, CAM-<NUM>, DA-<NUM>, ARI-<NUM>, ARI-<NUM>, Exenatide-XTEN and Glucagon-Xten.

Basic salts are e.g. salts having a cation selected from an alkali or alkaline earth metal, e.g. Na+, or K+, or Ca2+, or an ammonium ion N+(R1)(R2)(R3)(R4), wherein R1 to R4 independently of each other mean: hydrogen, an optionally substituted C1-C6-alkyl group, an optionally substituted C2-C6-alkenyl group, an optionally substituted C6-C10-aryl group, or an optionally substituted C6-C10-heteroaryl group.

Claim 1:
An autoinjector (<NUM>) comprising:
- a syringe carrier (<NUM>) and
- a case (<NUM>) adapted to receive the syringe carrier (<NUM>),
wherein the syringe carrier (<NUM>) is releasably holdable in the case (<NUM>), and
wherein the syringe carrier (<NUM>) comprises:
- a housing (<NUM>) adapted to receive a syringe (<NUM>) having a needle (<NUM>) encapsulated by a removable protective needle sheath (<NUM>), and
- two or more flexible arms (<NUM>) protruding inwards in a relaxed state and adapted to couple with a distal shoulder of the syringe (<NUM>) in a mounted position, wherein the flexible arms (<NUM>) are adapted to deflect radially outwards in a pre-assembled position of the syringe (<NUM>) in the syringe carrier (<NUM>), wherein in the mounted position the flexible arms (<NUM>) are allowed to return into the relaxed state due, in part, to an axial force (F2) operating on the syringe carrier (<NUM>),
characterised in that
the case (<NUM>) comprises at least one inwardly directed edge (<NUM>.<NUM>), and wherein the at least one inwardly directed edge (<NUM>.<NUM>) of the case (<NUM>) is adapted to further inwardly deflect the flexible arms (<NUM>) in the mounted position when the axial force (F2) operates onto the syringe carrier (<NUM>), forcing the syringe (<NUM>) and the protective needle sheath apart.