Patent Description:
Many medicament delivery devices, such as injectors, are often developed for self-administration where the user performs the injection. In some medicament delivery devices, a distal end of an injection needle protrudes into the interior of a container. This could be a drawback if the medicament reacts with the material of the injection needle when exposed for a period of time. In that respect, it is desirable to have the distal end of the injection needle outside the container until the injection is to be performed. On the other hand, this then requires that the distal end of the injection needle could be moved fairly easily into the container and also that the distal end of the injection needle is kept in a sterile environment until it is moved into the container.

Some types of medicaments can be stored for a long time and may be filled in containers, such as cartridges, syringes, ampoules, canisters or the like, containing a ready-to-use medicament in liquid state. However, some types of medicaments are a mixture of two substances, typically a medicament agent (such as lyophilized, powdered or concentrated liquid) and a diluent (such as water, dextrose solution or saline solution). These types of medicaments cannot be pre-mixed and stored for a long time because the medicament agent is unstable and will lose its effect quickly due to degradation. Hence, a user has to perform the mixing within a limited time period prior to the delivery of a dose of medicament by operating a medicament delivery device. Furthermore, some types of medicaments are sensitive to fast mixing and thus they must be mixed slowly.

In order to facilitate the mixing, a number of containers for medicament have been developed comprising at least two chambers, known as multi-chamber containers. Multi-chamber containers typically comprise a first chamber containing the medicament agent and at least one second chamber containing the diluent. These chambers may be sealed off with a stopper such that the medicament agents do not become degraded. When the medicament agent is to be mixed shortly before administering and the stopper is moved, redirecting passages are opened between the chambers. The passages allow the mixing of the medicament agent and the diluent. After sufficient mixing, the medicament is ready for delivery. Normally, delivery is performed by using injection devices wherein the multi-chamber container is arranged, more specifically in a container holder. After the mixing is performed, an injection needle having a needle sheath must be attached to the container holder and the. The step of attaching the injection needle to the container holder and thereafter removing the needle sheath is cumbersome and complicated for some users.

<CIT> discloses an injection needle assembly having opposite distal and proximal ends, comprising: a retainer member configured to be connectable to a medicament container; a hub configured to be coaxially displaceable within the retainer member and provided with an injection needle having proximal and distal pointed ends; and a cap member interactively connected to both the hub and to the retainer member.

<CIT> an injection device for manually penetrating a needle arranged to the device and automatically injecting a medicament mixture.

<CIT> discloses a multi-chamber injector wherein the medicaments are mixed by screwing the container holder into the casing and wherein the needle assembly is screwed into the container holder to pierce the sealing membrane of the container.

<CIT> discloses a multi-chamber injector wherein the container holder is screwed into the casing to mix the medicaments.

In the present disclosure, when the term "distal direction" is used, this refers to the direction pointing away from the dose delivery site during use of the medicament delivery device. When the term "distal part/end" is used, this refers to the part/end of the delivery device, or the parts/ends of the members thereof, which under use of the medicament delivery device is/are located furthest away from the dose delivery site. Correspondingly, when the term "proximal direction" is used, this refers to the direction pointing towards the dose delivery site during use of the medicament delivery device. When the term "proximal part/end" is used, this refers to the part/end of the delivery device, or the parts/ends of the members thereof, which under use of the medicament delivery device is/are located closest to the dose delivery site.

Further, the terms "longitudinal", "longitudinally", "axially" and "axial" refer to a direction extending from the proximal end to the distal end and along the device or components thereof, typically in the direction of the longest extension of the device and/or component.

Similarly, the terms "transverse", "transversal" and "transversally" refer to a direction generally perpendicular to the longitudinal direction.

One object of the present disclosure is to provide a container holder assembly for a medicament delivery device and which container assembly is configured to receive a multi-chamber container therein, and which container holder assembly improves usability of the medicament delivery device.

A further object of the present disclosure is to provide a container holder assembly for a medicament delivery device, which container holder assembly has a simple, cheap and/or reliable design.

A still further object of the present disclosure is to provide a container holder assembly for a medicament delivery device, which container holder assembly enables a proximal end of an injection needle to be kept sterile outside a multi-chamber container prior to mixing of at least two substances in the multi-chamber container.

A still further object of the present disclosure is to provide a container holder assembly for a medicament delivery device, which container holder assembly enables multiple use of an actuator device of the medicament delivery device.

A still further object of the present disclosure is to provide a container holder assembly for a medicament delivery device, which container holder assembly solving several or all of the foregoing objects in combination.

A still further object of the present disclosure is to provide a medicament delivery device comprising a container holder assembly, which medicament delivery device solves one, several or all of the foregoing objects.

Another object of the present disclosure is to provide a container holder assembly adapted to receive a multi-chamber container therein and configured to be connectable to a medicament delivery device such that a mixing of components within the multi-chamber container is achieved by manually moving the container holder assembly into the medicament delivery device, more specifically by rotation/screwing.

According to one aspect, there is provided a container holder assembly for a medicament delivery device, the container holder assembly comprising a container holder and a needle assembly, wherein the container holder comprises a distal tubular body for receiving a multi-chamber container therein, the distal tubular body comprising an external surface and a distal body engaging structure on the external surface configured to movably engage an actuator device of the medicament delivery device in order to releasably connect the container holder to the actuator device; and a proximal tubular part comprising a proximal body engaging structure connected to the needle assembly; wherein the needle assembly comprises a hub having an injection needle with a distal needle end and a proximal needle end, the distal needle end being isolated from the multi-chamber container when the multi-chamber container is received in the distal tubular body.

The container holder assembly according enables a medicament delivery device to be delivered to a user with a pre-assembled needle assembly. The container holder assembly further enables connection to an actuator device prior to a medicament dose expulsion and disconnection from the actuator device after the medicament dose expulsion.

The injection needle may be fixedly held by the hub. The proximal needle end may extend proximally from the hub and the distal needle end may extend distally from the hub. The hub may be configured to be axially displaced relative to the container holder.

The distal tubular body may be elongated along a longitudinal axis of the container holder assembly. The distal tubular body, the proximal tubular part, the hub and/or the injection needle may be substantially coaxial, or coaxial, with the longitudinal axis.

The distal tubular body may be substantially cylindrical, or cylindrical. In this case, an interior length of the distal tubular body may be at least two times, such as at least three time, such as at least five times, an inner diameter of the distal tubular body.

The needle assembly is pre-assembled to the container holder before the multi-chamber container is received in the distal tubular body.

The distal body engaging structure may be an external thread. The external thread may be continuous or discontinuous. With external thread is meant an exterior thread. Thus, the external thread may comprise a protrusion, a recess, or both.

The distal body engaging structure may be configured to threadingly engage a housing part of the medicament delivery device. To this end, the distal body engaging structure may or may not be a thread. As a possible alternative, the distal body engaging structure may comprise one or more protrusions threadingly engaging with a thread in the housing part. However, it is also feasible that the distal body is configured to linearly engage the housing part of the medicament delivery device such that distal body can be linearly moved into the housing part without rotation.

The distal tubular body may comprise at least one engaging body structure arranged to releasably engage at least one engageable device feature in the housing part. Each of the at least one engaging body structure may be a flexible protrusion, such as a flexible tab.

The proximal body engaging structure may be an external thread for threadingly engaging the needle assembly. In addition, the proximal tubular part may comprise a proximal internal engaging structure for threadingly engaging the hub. However, it is also feasible that the proximal body engaging structure may be an external bayonet structure for engaging the needle assembly, and the proximal tubular part may comprise a proximal internal engaging structure for linearly engaging the hub without rotation.

The needle assembly may further comprise a cap. The cap may be arranged to cause axial distal displacement of the hub by manual rotation of the cap. However, it is also feasible that the cap may be arranged to cause axial distal displacement of the hub by a manual linear movement of the cap without roation.

The distal needle end may be arranged to penetrate a membrane arranged at a proximal end of the multi-chamber container by means of the axial distal displacement of the hub. The container holder assembly may further comprise a sterile barrier between the membrane and the hub. The sterile barrier may for example be provided in the proximal tubular part. Also the sterile barrier may be penetrated by the distal needle end by means of the axial distal displacement of the hub.

The needle assembly may further comprise a needle cover covering the injection needle, the needle cover comprising a distal cover engaging structure engaging the proximal body engaging structure to connect the proximal tubular part to the needle assembly. The needle cover and the cap may be an integral component. Alternatively, the cap may be provided outside the needle cover. In this case, the needle assembly may further comprise a clutch. The cap may cooperate with the needle cover via the clutch such that when the user rotates the cap in one direction, the cap and the needle cover rotate together and move proximally along the longitudinal axis. When the needle cover rotates, the hub rotates in the same direction but also moves distally along the longitudinal axis. In this way, the cap and the needle cover can be removed at the same time as, or slightly after, the distal needle end pierces the membrane of the multi-chamber container by rotation of the cap. The clutch may be a ratcheting freewheel mechanism.

The container holder assembly further comprises a tamper indication member. The tamper indication member is unbroken until the cap is removed from the container holder <NUM>. The tamper indication member breaks to indicate tampering.

According to a further aspect, there is provided a medicament delivery device comprising a container holder assembly according to the present disclosure. The medicament delivery device may be disposable or for multiple use. The medicament delivery device may be an injection device.

The medicament delivery device may further comprise an actuator device having a housing part. In this case, the medicament delivery device may be arranged to cause mixing of at least two substances in the multi-chamber container by manually moving the container holder into the housing part, e.g. by threading engagement. The actuator device may be disposable or for multiple use.

The housing part may comprise at least two engageable device features arranged to be engaged by the engaging body structure at different axial positions of the distal tubular body relative to the housing part. Each engageable device feature may be a recess.

In the following, a container holder assembly for a medicament delivery device and a medicament delivery device comprising a container holder assembly, will be described. The same or similar reference numerals will be used to denote the same or similar structural features.

<FIG> schematically represents a perspective view of a medicament delivery device <NUM>. <FIG> schematically represents a further perspective view of the medicament delivery device <NUM>. With collective reference to <FIG> and <FIG>, the medicament delivery device <NUM> of this example is an injection device. The medicament delivery device <NUM> comprises a container holder assembly <NUM> and an actuator device <NUM>. In <FIG> and <FIG>, a longitudinal axis <NUM> of the medicament delivery device <NUM> is shown.

The container holder assembly <NUM> comprises a container holder <NUM> and a needle assembly <NUM>. The container holder <NUM> is connected to the needle assembly <NUM>. <FIG> and <FIG> illustrate the medicament delivery device <NUM> as received by the user. Thus, the medicament delivery device <NUM> is delivered with the needle assembly <NUM> connected to the container holder <NUM>. The actuator device <NUM> may be for multiple use and the container holder assembly <NUM> may be disposable.

The container holder <NUM> comprises a distal tubular body <NUM> and a proximal tubular part <NUM>. A multi-chamber container (not shown) is accommodated inside the distal tubular body <NUM>. The distal tubular body <NUM> comprises an external surface. On the external surface of the distal tubular body <NUM>, a distal body engaging structure <NUM> is provided. The distal body engaging structure <NUM> is exemplified as an external thread, here a continuous external thread.

The distal tubular body <NUM> of this example further comprises a first indicator <NUM>, a second indicator <NUM> and a third indicator <NUM>, indicated by the numbers "<NUM>", "<NUM>" and "<NUM>", respectively. The first indicator <NUM> and the second indicator <NUM> are arranged on one side of the distal tubular body <NUM>, and the third indicator <NUM> is arranged on an opposite side of the distal tubular body <NUM>. The first indicator <NUM> is arranged distally of the second indicator <NUM> and the third indicator <NUM>, the second indicator <NUM> is arranged between the first indicator <NUM> and the third indicator <NUM>, and the third indicator <NUM> is arranged proximally of the first indicator <NUM> and the second indicator <NUM>.

The container holder <NUM> further comprises two wings <NUM>. In this example, the wings <NUM> are provided on the distal tubular body <NUM>. The wings <NUM> assist the user to rotate the container holder <NUM>.

The needle assembly <NUM> of this example comprises a cap <NUM>. The cap <NUM> is provided around an injection needle (not shown). The cap <NUM> is generally cylindrical.

The container holder assembly <NUM> further comprises a tamper indication member <NUM>. In <FIG> and <FIG>, the tamper indication member <NUM> is unbroken.

When the cap <NUM> is removed from the container holder <NUM>, the tamper indication member <NUM> breaks to indicate tampering.

The actuator device <NUM> comprises a housing part <NUM>. The medicament delivery device <NUM> is configured to cause mixing of at least two substances in the multi-chamber container by manually moving the container holder <NUM> into the housing part <NUM>.

By means of the distal body engaging structure <NUM>, the distal tubular body <NUM> can movable engage the housing part <NUM> and the distal tubular body <NUM> is releasably connected to the housing part <NUM>. Thus, the container holder <NUM> or the entire container holder assembly <NUM> can be entirely separated from the housing part <NUM>. In this example, the distal tubular body <NUM> threadingly engages the housing part <NUM> by means of the distal body engaging structure <NUM>.

The housing part <NUM> of this example is cylindrical. The container holder <NUM> can be at least partly received inside the housing part <NUM>.

The actuator device <NUM> of this example further comprises a housing part <NUM>. Thus, the housing part <NUM> is a proximal housing part and the housing part <NUM> is a distal housing part. In this example, the distal housing part <NUM> is threadingly connected to the proximal housing part <NUM>.

The actuator device <NUM> of this example further comprises a button <NUM>. The button <NUM> is arranged at a distal end of the actuator device <NUM>.

The housing part <NUM> comprises an opening <NUM>. As shown in <FIG>, the first indicator <NUM> is aligned with the opening <NUM> and is visible through the opening <NUM>. Since the first indicator <NUM> is aligned with the opening <NUM>, the container holder <NUM> is in a first position with respect to the housing part <NUM>. The second indicator <NUM> and the third indicator <NUM> can also be aligned with, and visible through, the opening <NUM> when the container holder <NUM> adopts a second position and a third position, respectively, along the longitudinal axis <NUM> with respect to the housing part <NUM>.

The housing part <NUM> further comprises a first engageable device feature here exemplified as a first recess <NUM>, a second engageable device feature here exemplified as a second recess <NUM>, and a third engageable device feature here exemplified as a third recess <NUM>. The distal tubular body <NUM> comprises an engaging body structure, here exemplified as a flexible tab <NUM>. In the illustrated first position of the container holder <NUM>, the flexible tab <NUM> releasably engages the first recess <NUM>. The flexible tab <NUM> further engages the second recess <NUM> and the third recess <NUM> when the container holder <NUM> adopts the second position and the third position, respectively. In this way, the container holder <NUM> can be accurately positioned relative to the housing part <NUM> and the user is provided with tactile and audible feedback when the flexible tab <NUM> engages the respective recess <NUM>, <NUM> and <NUM>.

<FIG> schematically represents a cross-sectional side view of the medicament delivery device <NUM>. In <FIG>, the multi-chamber container <NUM> can be seen. The multi-chamber container <NUM> of this example is a dual-chamber container comprising a proximal stopper <NUM> and a distal stopper <NUM>.

As shown in <FIG>, the needle assembly <NUM> comprises, in addition to the cap <NUM>, a hub <NUM> having an injection needle <NUM>. Also the hub <NUM> and the injection needle <NUM> are concentric with respect to the longitudinal axis <NUM>. The injection needle <NUM> is fixedly held by the hub <NUM>. The needle assembly <NUM> is configured such that manual rotation of the cap <NUM> in one direction is translated to a distal movement of the hub <NUM> along the longitudinal axis <NUM>.

The needle assembly <NUM> of this example further comprises a needle cover <NUM>. The needle cover <NUM> is generally cylindrical and covers the injection needle <NUM>. The needle cover <NUM> is provided radially outside the injection needle <NUM> and the hub <NUM>, and radially inside the cap <NUM> (with respect to the longitudinal axis <NUM>).

The needle assembly <NUM> of this specific example further comprises a clutch <NUM>. The clutch <NUM> is provided between the cap <NUM> and the needle cover <NUM>. The clutch <NUM> transmits rotation of the cap <NUM> in one direction to a rotation of the needle cover <NUM>, the hub <NUM> and the injection needle <NUM>, but does not transmit rotation of the cap <NUM> in an opposite direction to any rotation of the needle cover <NUM>, the hub <NUM> or the injection needle <NUM>.

As shown in <FIG>, the distal tubular body <NUM> is elongated along the longitudinal axis <NUM>. A length of the distal tubular body <NUM> along the longitudinal axis <NUM> is more than five times an interior diameter of the distal tubular body <NUM>.

As further shown in <FIG>, the housing part <NUM> comprises a housing engaging structure <NUM>, here exemplified as a relatively short threaded portion at a proximal interior end of the housing part <NUM>. The distal body engaging structure <NUM> threadingly engages the housing engaging structure <NUM>.

<FIG> further shows that the actuator device <NUM> comprises an actuator <NUM>, an actuator sleeve <NUM>, a locking spring <NUM>, a plunger rod <NUM>, a plunger spring <NUM> and a guide rod <NUM>. The plunger spring <NUM> surrounds the guide rod <NUM>. The plunger rod <NUM> surrounds the plunger spring <NUM>. The actuator <NUM>, the actuator sleeve <NUM> and the locking spring <NUM> surround the plunger rod <NUM>. In the first position of the container holder <NUM> illustrated in <FIG>, the actuator sleeve <NUM> surrounds the actuator <NUM>.

<FIG> schematically represents a cross-sectional and partially exploded perspective view of the container holder assembly <NUM>, <FIG> schematically represents a cross-sectional partial side view of the container holder assembly <NUM>, and <FIG> schematically represents a cross-sectional and perspective partial side view of the container holder assembly <NUM>. With collective reference to <FIG>, a proximal needle end <NUM> and a distal needle end <NUM> of the injection needle <NUM> can be seen. The proximal needle end <NUM> extends proximally from the hub <NUM> and the distal needle end <NUM> extends distally from the hub <NUM>.

As shown in <FIG>, the multi-chamber container <NUM> comprises a membrane <NUM> at a proximal end thereof. The multi-chamber container <NUM> is entirely accommodated inside the container holder <NUM>. A major part of the multi-chamber container <NUM> is accommodated inside the distal tubular body <NUM> and a proximal end of the multi-chamber container <NUM> is accommodated inside the proximal tubular part <NUM>. The multi-chamber container <NUM> of this example is attached to the container holder <NUM> by means of a snap-fit connection to the interior of the proximal tubular part <NUM>.

The container holder <NUM> further comprises a sterile barrier <NUM>, here exemplified as a transverse wall. The barrier <NUM> sealingly closes a proximal interior portion of the proximal tubular part <NUM> from a distal interior portion of the proximal tubular part <NUM>.

In <FIG> and <FIG>, it is shown that the distal needle end <NUM> is isolated from the multi-chamber container <NUM> when the multi-chamber container <NUM> is received in the distal tubular body <NUM>. The distal needle end <NUM> is separated from the multi-chamber container <NUM> by means of the membrane <NUM> and the barrier <NUM>.

As shown in <FIG>, the proximal tubular part <NUM> comprises a proximal body engaging structure <NUM>, here exemplified as a proximal external thread. The needle cover <NUM> comprises a distal cover engaging structure <NUM>, here exemplified as a distal interior thread. The needle cover <NUM> is connected to the proximal tubular part <NUM> by means of a threaded engagement between the distal cover engaging structure <NUM> and the proximal body engaging structure <NUM>. In this way, the needle assembly <NUM> is connected to the proximal tubular part <NUM> by means of the proximal body engaging structure <NUM>.

The proximal tubular part <NUM> further comprises a proximal internal engaging structure <NUM>, here exemplified as a proximal internal thread. The hub <NUM> comprises a distal external engaging structure <NUM>, here exemplified as a distal external thread. The hub <NUM> is connected to the proximal tubular part <NUM> by means of a threaded engagement between the distal external engaging structure <NUM> and the proximal internal engaging structure <NUM>.

The hub <NUM> further comprises proximal external grooves <NUM>. The needle cover <NUM> further comprises interior ribs <NUM>. The interior ribs <NUM> extend parallel with the longitudinal axis <NUM>, in this example along more than half of a length of the needle cover <NUM>. The proximal external grooves <NUM> engage a respective interior rib <NUM>. By means of this engagement, rotation of the needle cover <NUM> is transmitted to a rotation of the hub <NUM>. The engagement however enables the hub <NUM> to move along the longitudinal axis <NUM> relative to the needle cover <NUM>.

<FIG> further shows that an arrow <NUM> is provided on the cap <NUM>. The arrow <NUM> indicates a rotational direction of the cap <NUM> in order to remove the cap <NUM>.

<FIG> schematically represents a cross-sectional and partially exploded perspective view of the actuator device <NUM>, <FIG> schematically represents a cross-sectional partial side view of the actuator device <NUM>, and <FIG> schematically represents a cross-sectional and perspective partial side view of the actuator device <NUM>. With collective reference to <FIG>, the actuator <NUM> comprises two hooks <NUM>, here provided at a distal end of the actuator <NUM>. The distal housing part <NUM> comprises a stop <NUM>. The stop <NUM> protrudes radially inwards (with respect to the longitudinal axis <NUM>). When the container holder <NUM> is in the first position with respect to the actuator device <NUM>, the actuator <NUM> is locked since the hooks <NUM> engage the stop <NUM>.

The actuator <NUM> of this example further comprises two flexible arms <NUM> projecting proximally. Each flexible arm <NUM> comprises a protrusion <NUM>. The plunger rod <NUM> comprises a circumferential groove <NUM>. When the container holder <NUM> is in the first position with respect to the actuator device <NUM>, the protrusions <NUM> are seated in the groove <NUM> and held in the groove <NUM> by the actuator sleeve <NUM>.

In the following, one exemplifying use of the medicament delivery device <NUM> will be described. The user may receive the medicament delivery device <NUM> with the container holder <NUM> connected to the housing part <NUM>, the needle assembly <NUM> connected to the container holder <NUM>, and a multi-chamber container <NUM> loaded into the distal tubular body <NUM>.

As an alternative, the user may receive the container holder assembly <NUM> comprising the container holder <NUM> and the needle assembly <NUM>, where the needle assembly <NUM> is connected to the container holder <NUM>, and where a multi-chamber container <NUM> is loaded into the distal tubular body <NUM>. In this case, the user may connect the container holder assembly <NUM> to the actuator device <NUM> by manually screwing the container holder <NUM> into the housing part <NUM> to the first position. The user knows when the housing part <NUM> has adopted the first position since the flexible tab <NUM> releasably engages the first recess <NUM> with a clicking sound and since the first indicator <NUM> (number "<NUM>") is visible through the opening <NUM>.

In order to mix different substances contained in the multi-chamber container <NUM>, the container holder <NUM> is manually rotated relatively to the housing part <NUM>, e.g. by means of the wings <NUM>. The container holder <NUM> thereby moves into the housing part <NUM> in a distal direction along the longitudinal axis <NUM>. During movement of the container holder <NUM> from the first position towards the second position, the plunger rod <NUM>, which is static in relation to the housing part <NUM>, eventually shifts the distal stopper <NUM> proximally into the multi-chamber container <NUM> such that medicaments inside the multi-chamber container <NUM> become completely mixed.

The manual rotation continues until the container holder <NUM> has moved from the first position to the second position. The user knows when the housing part <NUM> has adopted the second position and that mixing has been completed since the flexible tab <NUM> releasably engages the second recess <NUM> with a clicking sound and since the second indicator <NUM> (number "<NUM>") is visible through the opening <NUM>.

In order to prime the medicament delivery device <NUM>, the user manually rotates the container holder <NUM> further relative to the housing part <NUM>. As the container holder <NUM> moves from the second position towards the third position, the container holder <NUM> pushes the actuator sleeve <NUM> distally. The distal movement of the actuator sleeve <NUM> forces the hooks <NUM> inwardly away from the stop <NUM> to thereby unlock the actuator <NUM>.

The manual rotation continues until the container holder <NUM> has moved from the second position to the third position. The user knows when the housing part <NUM> has adopted the third position and that priming has been completed since the flexible tab <NUM> releasably engages the third recess <NUM> with a clicking sound and since the third indicator <NUM> (number "<NUM>") is visible through the opening <NUM>.

Either before or after priming, the user grabs and rotates the cap <NUM> in the direction illustrated by arrow <NUM> (<FIG>) about the longitudinal axis <NUM>. The rotation of the cap <NUM> in this direction is transmitted by the clutch <NUM> to a rotation in the same direction of the needle cover <NUM>. As the needle cover <NUM> is rotated, the needle cover <NUM> moves proximally relative to the proximal tubular part <NUM> due to the engagement between the distal cover engaging structure <NUM> and the proximal body engaging structure <NUM>. Due to this relative movement between the needle cover <NUM> and the proximal tubular part <NUM>, the tamper indication member <NUM> breaks.

Furthermore, as the needle cover <NUM> is rotated, the hub <NUM> is rotated in the same direction due to the engagement between the interior ribs <NUM> and the proximal external grooves <NUM>. As the hub <NUM> is rotated, the hub <NUM> travels distally along the longitudinal axis <NUM> due to the engagement between the distal external engaging structure <NUM> and the proximal internal engaging structure <NUM>. As the hub <NUM> travels distally, the distal needle end <NUM> pierces the barrier <NUM> and the membrane <NUM>.

When the cap <NUM> is rotated further, the needle cover <NUM> eventually disengages completely from the proximal tubular part <NUM>. The cap <NUM>, the clutch <NUM> and the needle cover <NUM> can then be removed to expose the proximal needle end <NUM>.

The proximal needle end <NUM> of the injection needle <NUM> then pierces an injection site of a user. When the user pushes the button <NUM>, the button <NUM> pushes the plunger rod <NUM> and forces the plunger rod <NUM> proximally. Since the protrusions <NUM> of the flexible arms <NUM> are engaged in the groove <NUM> of the plunger rod <NUM>, the actuator is moved proximally by the plunger rod <NUM>. When the flexible arms <NUM> pass the proximal end of the actuator sleeve <NUM>, the plunger rod <NUM> is released and thereby delivers the medicament through the injection needle <NUM>. Thus, by pressing the button <NUM>, the medicament is automatically expelled into the injection site.

When the medicament has been expelled from the multi-chamber container <NUM>, the plunger spring <NUM> forces the actuator distally against the button <NUM> and thereby produces an audible and tactile feedback to the user indicating injection completion. The container holder <NUM> may then be screwed out from the housing part <NUM> until the container holder <NUM> is disconnected from the actuator device <NUM>. The container holder <NUM> and the empty multi-chamber container <NUM> can then be discarded and the actuator device <NUM> can be loaded with a new container holder assembly <NUM> comprising a new container holder <NUM> holding a full multi-chamber container <NUM> and being connected to a new needle assembly <NUM>.

Claim 1:
A medicament delivery device (<NUM>) comprising an actuator device (<NUM>) and a container holder assembly (<NUM>), the actuator device (<NUM>) comprising a housing part (<NUM>), the container holder assembly (<NUM>) comprising a container holder (<NUM>) and a needle assembly (<NUM>), wherein the container holder (<NUM>) comprises:
- a distal tubular body (<NUM>) for receiving a multi-chamber container (<NUM>) therein, the distal tubular body (<NUM>) comprising an external surface and a distal body engaging structure (<NUM>) on the external surface configured to movably engage the housing part (<NUM>) in order to releasably connect the container holder (<NUM>) to the actuator device (<NUM>), the container holder (<NUM>) being manually rotatable relatively to the housing part (<NUM>) and thereby moveable into the housing part (<NUM>) in distal direction from a first position towards at least a second position, a movement from the first position to the second position causing the medicament inside the multi-chamber container (<NUM>) to mix; and
- a proximal tubular part (<NUM>) comprising a proximal body engaging structure (<NUM>) connected to the needle assembly (<NUM>),
wherein the needle assembly (<NUM>) is pre-assembled to the container holder (<NUM>) before the multi-chamber container (<NUM>) is received in the distal tubular body (<NUM>);
wherein the needle assembly (<NUM>) comprises:
- a hub (<NUM>) having an injection needle (<NUM>) with a distal needle end (<NUM>) and a proximal needle end (<NUM>), the distal needle end (<NUM>) being isolated from the multi-chamber container (<NUM>) when the multi-chamber container (<NUM>) is received in the distal tubular body (<NUM>), the distal needle end (<NUM>) being separated from the multi-chamber container (<NUM>) by means of a membrane (<NUM>) and a barrier (<NUM>)
- a cap (<NUM>) removably attached to the container holder (<NUM>), a manual rotation of the cap (<NUM>) causing the hub (<NUM>) to move distally, thereby causing the distal needle end (<NUM>) to pierce the membrane (<NUM>) and the barrier (<NUM>).