Patent Description:
<CIT> discloses a feedback mechanism for a drug delivery device comprising a wedge structure interacting with a spring arm of an element rotating relative to the wedge structure during dose dispensing such that a feedback signal is generated indicating that the set dose has been injected.

It is an object of the present invention to provide an assembly for a drug delivery device having improved properties.

An assembly for a drug delivery device is provided, the assembly comprising a feedback feature. The feedback feature is configured to indicate an end of a dispense operation to a user by giving an audible and/or tactile feedback. The audible feedback may be, for example, an audible click. The tactile feedback may be, for example, an impact on the skin of a user, in particular on a user's finger. For example, the tactile feedback may be a vibration of a part of the assembly. In particular, the feedback may be a well-defined signal. In particular, the feedback may indicate to a user that the actuator may be released and the device may be withdrawn from a user's skin.

The advantage of a feedback feature being configured to indicate the end of a dispense operation is that a clear indication is given to a user when a dispense operation has been completed. Thereby, the use of the drug delivery device may be simplified for a user. Furthermore, the dosing accuracy of a drug delivery device may be increased. In particular, it may be inhibited that a user interrupts a dispense operation, for example by withdrawing the drug delivery device from the skin, before a complete dose has been delivered. Furthermore, such a feedback provides an additional benefit for visually impaired users.

According to one embodiment, the assembly comprises an actuator, which is configured to be operated by a user in order to dispense a dose. A feedback feature may create a feedback when the actuator reaches an end position at the end of a dispense operation. The end position of the actuator may be a most distal position of the actuator. The term "most distal position" may describe a position of a part of the assembly which is closest to a dispensing end of the drug delivery device. In particular, the actuator may be in its end position when it is fully depressed into the drug delivery device. The actuator may be configured as a button. According to one embodiment, the feedback feature may be an integral part of the actuator.

According to one embodiment, the assembly comprises a member which is configured to interact with the feedback feature. The member is configured to axially move when it does not interact with the feedback feature. For example, the member is configured to axially move during an initial phase of a dispense operation. The interaction of the axially moveable member with the feedback feature may cause a feedback. According to another embodiment, the member may be a driver. The driver may be a part of the assembly which is configured to drive a piston rod in order to dispense a dose of medication. In particular, the driver may be engaged with the piston rod. During a dispense operation, the driver may be moved towards a distal end of the device due to a movement of the actuator. According to a further embodiment, the member may be an indicator, for example a number sleeve. According to a further embodiment, the member may be a separate member, for example a sleeve member.

According to one embodiment, the member may axially move with respect to a housing of the drug delivery device between two stops at least during the setting of a dose. During the dispensing of a dose, in particular when the actuator approaches its end position, the member may be temporarily restrained between these two stops. Thereby, the member may be temporarily axially fixed. In particular, the member may be axially fixed when it interacts with the feedback feature, i. when the actuator contacts the feedback feature.

According to one embodiment, the feedback feature is configured to snap through when it is compressed above a certain load. Thereby, a feedback may be given to a user. In particular, the feedback feature is configured to snap through at the end of a dispense operation. In particular, the feedback feature is configured to snap through when the actuator reaches its end position. Initially during compression of the feedback feature, the stiffness of the feedback feature may remain fairly constant. At a certain point, the stiffness of the feedback feature may reduce significantly. Thereby, the force required to cause a further deflection of the feedback feature may decrease. This may cause the snap-through behaviour of the feedback feature.

According to one embodiment, the feedback feature may be configured to be compressed between two parts of the assembly. For example, the feedback feature may be compressed between the actuator and the axially moveable member. Alternatively, the feedback feature could be compressed between the housing and the driver.

According to one embodiment, the feedback feature may comprise the shape of a dome. In particular, the feedback feature may be configured as a snap dome. In particular, the feedback feature may comprise the shape of an arched disk.

According to one embodiment, the feedback feature comprises at least one recess. The recess may be, for example, a concave cut out. Due to the at least one recess, the feedback feature may comprise a sufficient flexibility. Thereby, the feedback feature may be configured to snap through when it is compressed above a certain load. In particular, the size and shape of the recess may influence the force which is necessary to cause the feedback feature to snap through.

According to one embodiment, the actuator interacts with the feedback feature. In particular, the actuator may interact with the feedback feature during a dispense operation. The feedback feature may be arranged between the actuator and another part of the drug delivery device. When the actuator approaches its end position during a dispense operation, the feedback feature may be clamped between the actuator and the other part. When the actuator is further moved towards the other part, the feedback feature may be compressed by the actuator. In particular, the force on the feedback feature increases when the actuator is further moved towards the other part. In particular, the actuator may exert a force on the feedback feature during a dispense operation. In an alternative embodiment, the feedback feature may be an integral part of the other part.

According to one embodiment, the feedback feature comprises a metal material. According to a further embodiment, the feedback feature may comprise a plastic material. Preferably, the feedback feature comprises a resilient material.

According to one embodiment, the feedback feature comprises an opening, wherein at least one element of the assembly extends through the opening. For example, the actuator may extend through the opening of the feedback feature. As a further example, the driver may extend through the opening of the feedback feature.

According to one embodiment, the feedback feature comprises a first feedback element and a second feedback element. The first feedback element may be configured to interact with the second feedback element. In particular, the first feedback element and the second feedback element may abut each other, in particular when the actuator approaches its end position. In particular, the second feedback element may exert a force on the first feedback element during the dispensing of a dose. Thereby, the first feedback element may be deflected by the second feedback element during a dispense operation. The first feedback element may be, for example, a resilient element. The second feedback element may be, for example, a rigid element. For example, the second feedback element may be a protrusion in a part of the assembly. In particular, the second feedback element may extend along the whole circumference of the part. For example, the second feedback element may be a protrusion which extends along an inner circumference of a body part of the assembly. When the first feedback element and the second feedback element interact with each other, an audible feedback may be created. The first feedback element may be an integral part of a part of the device. For example, the first feedback element may be an integral part of the actuator. Alternatively, the first feedback element may be an integral part of the indicator.

According to one embodiment, the feedback feature comprises at least one resilient arm. In particular, the first feedback element may comprise at least one resilient arm. Preferably, the feedback feature comprises two or more resilient arms. Preferably, the at least one resilient arm extends in a proximal direction. The proximal direction may be a direction away from the dispensing end of the device. In an alternative embodiment, the at least one resilient arm extends in a distal direction. According to one embodiment, the at least one resilient arm may stick out from an element of the assembly in a radial direction. During a dispense operation, the at least one resilient arm may be deflected, in particular in a radial direction. Preferably, the at least one resilient arm is integrally formed with a part of the assembly. Preferably, the at least one arm is attached to, in particular integrally moulded with an injection moulded part of the device.

According to one embodiment, the assembly comprises a rotation member which is configured to rotate during dispensing of a dose. The first feedback element of the feedback feature may be located at the rotation member. The rotation member may be, for example, an indicator, in particular a number sleeve. For example, the feedback feature may be a resilient arm which is attached to the rotation member. In particular, the feedback element may extend along a circumferential direction of the rotation member. Preferably, the feedback feature is configured to be deflected in a radial inward direction.

According to one embodiment, the feedback feature is configured to give a feedback to a user during the dispensing of a dose. In particular, the feedback may indicate that the dispensing is ongoing. As an example, a first feedback element may permanently interact with a second feedback element during a dispense operation. At the end of a dispense operation, the feedback may be increased.

According to one embodiment, the assembly comprises an enhancement feature. The enhancement feature may be configured to enhance a feedback signal. The enhancement feature may be, for example, a protrusion in one part of the assembly. According to one embodiment, the first feedback element is configured to interact with the enhancement feature at the end of the dispense operation. Preferably, the first feedback element does not interact with the enhancement feature prior to the end of the dispense operation. The enhancement feature may be configured to reinforce the interaction of the first feedback element with the second feedback element. The second feedback element may comprise a plurality of protrusions or splines. For example, the enhancement feature may increase the stiffness of the first feedback element. In particular, the enhancement feature may be in contact with the first feedback element at the end of a dispense operation. In particular, the enhancement feature may be in contact with a surface of the first feedback element which is faced towards a longitudinal axis of the device. Thereby, the enhancement feature may limit a deflection of the first feedback element, in particular in a radially inward direction.

According to one embodiment, the second feedback element is configured as a thread. For example, the second feedback element may comprise a thread in a body part of the assembly. The first feedback element may be a resilient arm, which is for example located at the rotation member and may extend along a circumference direction of the rotation member. During the dispensing of a dose, the first feedback element may interact with the thread of the second feedback element. In particular, the first feedback element may be preloaded due to the interaction with the thread of the second feedback element. For example, the first feedback element may be strained in an axial or radial direction. The second feedback element may further comprise a step. The step may be located at a distal end of the thread. The step may extend in an axial or radial direction. When the first feedback element reaches the step at the end of a dispense operation, the first feedback element may, due to its preload, drop of the step. Thereby, the first feedback element may hit the wall of the body part. Thereby, an audible feedback may be created.

Furthermore, a drug delivery device is provided, the drug delivery device comprising an assembly which is configured as previously described. In particular, the drug delivery device may comprise a feedback feature, which is configured to indicate an end of a dispense operation to a user by giving an audible and/or tactile feedback.

The drug delivery device may be an injection device. The drug delivery device may be a pen-type device. The drug delivery device may be a variable dose device such that a user can select the size of a dose. The drug delivery device may be configured for multiple dose applications. The medication may be delivered to a user by means of a needle. The device may be delivered to a user in a fully assembled condition ready for use. The drug delivery device may be a disposable device. The term "disposable" means that the drug delivery device cannot be reused after an available amount of medication has been delivered from the drug delivery device. The drug delivery device may be configured to deliver a liquid medication. The medication may be, for example, insulin.

The term "medication", as used herein, preferably means a pharmaceutical formulation containing at least one pharmaceutically active compound,.

Hormones are for example hypophysis hormones or hypothalamus hormones or regulatory active peptides and their antagonists as listed in Rote Liste, ed. <NUM>, Chapter <NUM>, such as Gonadotropine (Follitropin, Lutropin, Choriongonadotropin, Menotropin), Somatropine (Somatropin), Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin, Buserelin, Nafarelin, Goserelin.

Antibodies are globular plasma proteins (~<NUM> kDa) that are also known as immunoglobulins which share a basic structure. As they have sugar chains added to amino acid residues, they are glycoproteins. The basic functional unit of each antibody is an immunoglobulin (Ig) monomer (containing only one Ig unit); secreted antibodies can also be dimeric with two Ig units as with IgA, tetrameric with four Ig units like teleost fish IgM, or pentameric with five Ig units, like mammalian IgM.

Further features, refinements and expediencies become apparent from the following description of the exemplary embodiments in connection with the figures.

<FIG> shows a drug delivery device <NUM>. In particular, the drug delivery device <NUM> is an injection device. The drug delivery device <NUM> is a variable dose device such that a user can select the size of a dose. The drug delivery device <NUM> is configured for multiple dose applications. The device can be delivered to a user in a fully assembled condition ready for use. The device has a low part count and is particularly attractive for cost-sensitive device applications.

The drug delivery device <NUM> comprises a housing <NUM>, an inner body <NUM>, an actuator <NUM>, an indicator <NUM>, a driver <NUM>, a piston rod <NUM>, a piston <NUM>, a last dose stop <NUM>, and a cartridge <NUM>. A needle arrangement comprising a needle hub and a needle cover may be provided as additional components.

The housing <NUM> is a generally tubular element. A distal part of the housing <NUM> forms a cartridge holder <NUM> for receiving the cartridge <NUM>.

The inner body <NUM> is a generally tubular element. The inner body <NUM> is received in the housing <NUM> and is permanently fixed therein to prevent any relative movement of the inner body <NUM> with respect to the housing <NUM>. An external thread <NUM> is provided on the outer surface of the inner body <NUM>. At its distal end, the inner body <NUM> comprises a further thread <NUM>.

The actuator <NUM> is configured as a button. The actuator <NUM> is rotationally and axially moveable with respect to the housing <NUM> and the inner body <NUM>. The actuator <NUM> is arranged at a proximal end of the drug delivery device <NUM>. The actuator <NUM> is configured to be operated in order to dispense a dose of medication.

The indicator <NUM> is a generally tubular element. In particular, the indicator <NUM> is configured as a rotation member <NUM>. In particular, the indicator <NUM> is configured to rotate with respect to the housing <NUM> during the setting and the dispensing of a dose. The indicator <NUM> is arranged concentrically around the inner body <NUM>. In particular, the indicator <NUM> comprises an internal thread <NUM> engaging with the external thread <NUM> of the inner body <NUM>. Thus, the indicator <NUM> is arranged between the inner body <NUM> and the housing <NUM>. A series of numbers is provided, e.g. printed, on the outer surface of the indicator <NUM>. The numbers are arranged on a helical line such that only one number or only a few numbers are visible through a window <NUM> of the housing <NUM>. The numbers indicate the amount of a set dose. At the end of a dose dispense operation, the indicator <NUM> may have returned in its initial position, thereby indicating the end of a dispense operation to a user.

The piston rod <NUM> is configured as a lead screw. In particular, the piston rod <NUM> comprises two counter-handed threads which overlap each other. One of the threads of the piston rod <NUM> engages with the inner thread <NUM> of the inner body <NUM>.

The driver <NUM> is a generally tubular element. An inner surface of the driver <NUM> has an inner thread <NUM> engaging with one of the external threads of the piston rod <NUM>. The driver <NUM> is at least partly located within the inner body <NUM>. A distal region of the driver <NUM> has an external thread <NUM>. The driver <NUM> is configured to rotate and axially move with respect to the housing <NUM> during the setting of a dose. During the dispensing of a dose, the driver <NUM> is axially moveable and rotationally fixed with respect to the housing <NUM>.

The last dose stop <NUM> is provided between the inner body <NUM> and the driver <NUM>. An internal thread of the last dose stop <NUM> engages with the external thread <NUM> of the driver <NUM>. The last dose stop <NUM> is configured to inhibit the setting of a dose which is larger than an amount of medication remaining in the cartridge <NUM>. This is achieved by the last dose stop <NUM> abutting an abutment feature of the driver <NUM> when a dose is set which corresponds to an amount of medication remaining in the cartridge <NUM>. The last dose stop <NUM> is configured as a nut.

In order to set a dose, the actuator <NUM> is rotated by a user. During the setting of a dose, the indicator <NUM> and the driver <NUM> are rotationally fixed with respect to the actuator <NUM>. Thereby, the actuator <NUM>, the indicator <NUM> and the driver <NUM> are rotated out of the housing <NUM>. Thereby, the driver <NUM> is rotated along the piston rod <NUM> in a proximal direction, while the piston rod <NUM> is axially and rotationally fixed with respect to the housing <NUM> during the setting of a dose. The indicator <NUM> is rotated along the thread <NUM> of the inner body <NUM>.

In order to dispense a dose, the actuator <NUM> is operated by a user. In particular, the actuator <NUM> is pushed in a direction towards a dispensing end of the device. During the dispensing of a dose, the actuator <NUM> and the driver <NUM> are rotationally fixed with respect to each other. The indicator <NUM> may rotate with respect to the actuator <NUM> and the driver <NUM> during the dispensing of a dose. Thereby, the indicator <NUM> may rotate back to its initial position and indicate the end of the dispense operation to a user. When the actuator <NUM> is operated, the driver <NUM> is also moved in a direction towards a dispensing end of the device. Thereby, the piston rod <NUM> is axially moved in a distal direction in order to dispense a dose of medication. In particular, the piston rod <NUM> is configured to rotate and axially move during the dispensing of a dose. When the actuator <NUM> has been operated and reached an end position, a feedback is given to a user. In particular, the feedback may indicate the end of a dispense operation. The end position of the actuator <NUM> may be its most distal position. In particular, the actuator <NUM> is in its end position when it is fully depressed.

In <FIG>, different embodiments of a feedback feature are shown, which may indicate an end of a dispense operation to a user. In particular, <FIG> and <FIG> show different assemblies <NUM> for a drug delivery device <NUM> comprising different embodiments of a feedback feature <NUM>. The embodiments are illustrated in the context of a drug delivery device <NUM> as shown in <FIG>, but are not limited thereto. In particular, the feedback feature <NUM> may also be used in a reusable device or in a device having a different drive mechanism.

The feedback may be an audible or tactile signal at the end of a dispense operation. This may improve the ease of use and the dose accuracy for a user, in particular for a visually impaired user. Furthermore, the signal can be used to indicate the start of a dwell period. At the end of a dispense operation, i. after a user has operated the actuator <NUM>, the dispensing of the full amount of a set dose may be delayed due to a slight deformation of the piston <NUM>. The dwell period is the time between the moment when the actuator <NUM> has reached its end position and the moment when the full amount of a dose has been dispensed. In particular, the dwell period may be the time the piston <NUM> needs after an operation of the actuator <NUM> to relax to its undeformed state.

<FIG> shows a section through a proximal part of a drug delivery device <NUM> according to <FIG> comprising a feedback feature <NUM>. A first feedback element <NUM> of the feedback feature <NUM> is arranged at the actuator <NUM>. The first feedback element <NUM> is integrally formed with the actuator <NUM>. In particular, the actuator <NUM> may be an injection-moulded part, wherein the first feedback element <NUM> may be integrally moulded with the actuator <NUM>. The first feedback element <NUM> comprises at least one, in particular two resilient arms <NUM>, which stick out from the actuator <NUM> in a radial direction. In particular, the resilient arms <NUM> stick out in a direction away from a longitudinal axis <NUM> of the drug delivery device <NUM>. The resilient arms <NUM> may be configured as a snap feature. In particular, the resilient arms <NUM> are configured to snap over a second feedback element <NUM> of the feedback feature <NUM>. The resilient arms <NUM> extend in a proximal direction. In particular, each resilient arm <NUM> has one connection point with a main body of the actuator <NUM> and one free end. The free end is faced towards a proximal end of the device <NUM>. The driver <NUM> comprises a cavity <NUM>, wherein the feedback feature <NUM>, in particular the resilient arms <NUM>, extend through the cavity <NUM>.

When the actuator <NUM> is actuated by a user, the actuator <NUM> and thereby the first feedback element <NUM> is moved in a direction towards a distal end of the device <NUM>. During the movement of the actuator <NUM> towards the distal end of the device <NUM>, the first feedback element <NUM> interacts with the second feedback element <NUM>. The second feedback element <NUM> is configured as a protrusion. The second feedback element <NUM> is located at the inner body <NUM>. The second feedback element <NUM> may be configured as a full ring detent feature. This is beneficial in the case that the actuator <NUM> may have any rotational alignment relative to the inner body <NUM>.

During the movement of the actuator <NUM> towards the distal end of the device <NUM>, the first feedback element <NUM> is deflected in a radial direction towards the longitudinal axis <NUM> of the device <NUM>, i.e. radially inwards. In particular, the resilient arms <NUM> are deflected by the second feedback element <NUM>. When the actuator <NUM> has reached its end position, in particular at the end of a dispense operation, the resilient arms <NUM> lose contact with the second feedback element <NUM> and snap back in a direction away from the longitudinal axis <NUM> of the device <NUM>. Thereby, an audible and/or tactile feedback is created. In an alternative embodiment, the first feedback element <NUM>, in particular the resilient arms <NUM>, may be located on the inner body <NUM>, and the second feedback element <NUM> may be located on the actuator <NUM>.

During the setting of a dose, when the actuator <NUM> is moved in a direction away from the dispensing end of the device <NUM>, the resilient arms <NUM> are again deflected radially inwards by the second feedback element <NUM>. Thereby, the resilient arms <NUM> may slide back over the second feedback element <NUM> such that they are again in a proximal position relative to the second feedback element <NUM>.

<FIG> shows a section through a proximal part of a further embodiment of a drug delivery device <NUM> with a feedback feature <NUM>. The feedback feature <NUM> comprises a first feedback element <NUM> and a second feedback element <NUM>. The first feedback element <NUM> is located at the inner body <NUM>. The first feedback element <NUM> comprises two resilient arms <NUM>. The resilient arms <NUM> stick out from the inner body <NUM> in a radial direction towards the longitudinal axis <NUM> of the drug delivery device <NUM>. The resilient arms <NUM> extend in a proximal direction. The first feedback element <NUM>, in particular the resilient arms <NUM>, interact with the second feedback element <NUM>. The second feedback element <NUM> is located at the driver <NUM>. In particular, the second feedback element <NUM> is configured as a protrusion on the driver <NUM>. Since the driver <NUM> can have any rotational alignment to the inner body <NUM>, the second feedback element <NUM> may be configured as a full ring detent feature.

The operating principle is similar to the embodiment described in <FIG>. During the movement of the actuator <NUM> towards a distal end of the device, the driver <NUM> is also moved towards the distal end of the device. Thereby, the first feedback element <NUM>, in particular the resilient arms <NUM>, are deflected in a radial direction away from the longitudinal axis <NUM> of the device <NUM>, i. radially outwards. When the actuator <NUM> has travelled its full distance, in particular at the end of a dispense operation, the first feedback element <NUM>, in particular the resilient arms <NUM>, lose contact with the second feedback element <NUM> of the driver and snap back in a direction towards the longitudinal axis <NUM> of the device. Thereby, an audible and/or tactile feedback is created. In an alternative embodiment, the first feedback element <NUM>, in particular the resilient arms <NUM>, may be located at the driver <NUM>, and the second feedback element <NUM> may be located at the inner body <NUM>.

During the setting of a dose, when the actuator <NUM> is moved in a direction away from the dispensing end of the device <NUM>, the resilient arms <NUM> are again deflected radially outwards by the second feedback element <NUM>. Thereby, the resilient arms <NUM> may slide back over the second feedback element <NUM> such that they are again in a distal position relative to the second feedback element <NUM>.

<FIG> show a section through a proximal part of a further embodiment of a drug delivery device <NUM> comprising a feedback feature <NUM>. The feedback feature <NUM> comprises a first feedback element <NUM> and a second feedback element <NUM>.

The first feedback element <NUM> is arranged at the indicator <NUM>. The first feedback element <NUM> may be an integral part of the indicator <NUM>. In particular, the first feedback element <NUM> extends along a circumferential direction of the indicator <NUM>. In particular, the first feedback element <NUM> comprises a resilient arm <NUM>. When the indicator <NUM> rotates relative to the actuator <NUM> and the inner body <NUM> during the dispensing of a dose, the first feedback element <NUM>, in particular the resilient arm <NUM>, interacts with a second feedback element (not shown) inside the actuator <NUM> to provide an audible click with each unit dispensed. The second feedback element inside the actuator <NUM> may comprise, for example, teeth or splines. At the inner body <NUM>, an enhancement feature <NUM> is arranged. The enhancement feature <NUM> is configured to interact with the first feedback element <NUM>.

<FIG> shows the interaction of the first feedback element <NUM> and the enhancement feature <NUM>. The enhancement feature <NUM> interacts with the first feedback element <NUM> at the end of a dispense operation. Due to the interaction of the first feedback element <NUM> and the enhancement feature <NUM>, support is provided to the first feedback element <NUM> at least when the final unit of a dose is injected. In particular, the enhancement feature <NUM> interacts with the first feedback element <NUM> such that a deflection of the first feedback element <NUM> in a radially inward direction is limited. Thereby, the stiffness of the first feedback element <NUM> in particular of the resilient arm <NUM>, is increased. Thereby, the interaction of the first feedback element <NUM> and the second feedback element inside the actuator <NUM> is increased. Thereby, a louder or a noticeably different click is produced, signalling to the user the end of a dispense operation.

<FIG> shows a further embodiment of a drug delivery device <NUM> comprising a feedback feature <NUM>. The feedback feature <NUM> is configured as a snap feature. In particular, the feedback feature <NUM> is configured as a snap dome. The feedback feature <NUM> comprises or consists of a metal material. The feedback feature <NUM> comprises an opening <NUM>, wherein the actuator <NUM> extends through the opening.

A feedback feature <NUM> being configured as a snap dome is shown in <FIG>. In particular, the feedback feature <NUM> is configured as an arched disc. Furthermore, the feedback feature <NUM> comprises at least one recess <NUM>. The recess <NUM> is configured as a concave cavity. In particular, the feedback feature <NUM> comprises four recesses <NUM>. Due to the cavities, the snap dome possesses a sufficient flexibility. The feedback feature <NUM> is configured to snap through when it is compressed above a certain load. Thereby, the feedback feature <NUM> creates an audible click and/or a tactile feedback at the end of a dispense operation.

In an alternative embodiment as shown in <FIG>, the feedback feature <NUM> is configured without any recess. Thereby, the feedback feature <NUM> may comprise a high stiffness. Thereby, the feedback signal may be more distinct. In particular, the feedback feature <NUM> is configured as an arched ring. In particular, the feedback feature <NUM> comprises an opening.

As illustrated in <FIG>, the feedback feature <NUM> is operated by an axially moveable member <NUM>. In particular, the axially moveable member <NUM> is a sleeve member <NUM> which is arranged between the actuator <NUM> and the indicator <NUM>. The sleeve member <NUM> can move axially relative to the actuator <NUM> between two stops <NUM>, <NUM> when it does not interact with the feedback feature <NUM>. The feedback feature <NUM> pushes apart the actuator <NUM> and the sleeve member <NUM> to preload the sleeve member <NUM> against one of these stops <NUM>, <NUM>. In particular, one stop <NUM> is provided by the housing <NUM> and the other stop <NUM> is provided by the actuator <NUM>. When the actuator <NUM> approaches its end position, the sleeve member <NUM> contacts the stop <NUM> at the housing <NUM>. When the actuator <NUM> is further moved towards its end position, the feedback feature <NUM> is compressed. Thereby, the feedback feature <NUM> is caused to snap, thereby creating an audible click. In particular, a clear audible and tactile feedback is provided for a user at the end of a dispense operation.

When the load which is exerted on the feedback feature <NUM> by the sleeve member <NUM> is released during the setting of a dose, the feedback feature <NUM> snaps back into its uncompressed shape. Thereby, the feedback feature <NUM> may push the actuator <NUM> to an extended position.

<FIG> shows a section through a proximal part of a further embodiment of a drug delivery device <NUM> comprising a feedback feature <NUM>. The embodiment shown in <FIG> is similar to the embodiment shown in <FIG>, apart from that the embodiment shown in <FIG> does not comprise a sleeve member <NUM>. The feedback feature <NUM> directly interacts with the actuator <NUM> and the housing <NUM>. In particular, the housing <NUM> comprises a collar <NUM>. The collar <NUM> is configured to interact with the feedback feature <NUM>. In particular, the feedback feature <NUM> is compressed between the collar <NUM> of the housing <NUM> and the actuator <NUM> when the actuator <NUM> approaches the housing <NUM> during the dispensing of a dose.

<FIG> shows a proximal part of a different embodiment of a drug delivery device <NUM> comprising a feedback feature <NUM>. The embodiment shown in <FIG> is similar to the embodiment shown in <FIG>, apart from that the feedback feature <NUM> is integrated into the axially moveable member <NUM>, which is configured as a sleeve member <NUM>. In particular, the sleeve member <NUM> may be an injection-moulded part, and the feedback feature <NUM> may be integrally moulded with the sleeve member <NUM>. The feedback feature <NUM> may be configured as a plastic dome or a series of resilient arms. The resilient arms may be arched, such that they form a dome with slots. The operating principle is the same as in the embodiment shown in <FIG>, with the feedback feature <NUM> snapping through, thereby creating an audible and/or tactile feedback for a user at the end of a dispense operation.

<FIG> shows a section through a proximal part of a further embodiment of the drug delivery device <NUM> comprising a feedback feature <NUM>. The feedback feature <NUM> is arranged between the indicator <NUM> and the housing <NUM>. In particular, the feedback feature <NUM> is positioned inside a cavity in the housing <NUM>. The feedback feature <NUM> is configured as a snap dome with a relatively large diameter. The actuator <NUM>, the driver <NUM>, the inner body <NUM> and a part of the housing <NUM> extend through the opening.

When the indicator <NUM> approaches its end-of-dispense position, it makes contact with the feedback feature <NUM> and compresses the feedback feature <NUM>, thereby causing it to undergo snap-through buckling. Thereby, an audible and/or tactile feedback is created to indicate the end of a dispense operation to a user.

<FIG> shows a section through a proximal part of a further embodiment of a drug delivery device <NUM> comprising a feedback feature <NUM>. The embodiment shown in <FIG> is similar to the embodiment shown in <FIG>, apart from that the feedback feature <NUM> is arranged between the driver <NUM> and the inner body <NUM>. The feedback feature <NUM> is arranged on a protrusion <NUM> of the inner body <NUM>. When the driver <NUM> approaches its end-of-dispense position, it makes contact with the feedback feature <NUM> and compresses the feedback feature <NUM>, thereby causing the feedback feature <NUM> to snap through. Thereby, an audible and/or tactile feedback is created, indicating the end of a dispense operation to a user.

<FIG> shows the actuator <NUM>, the indicator <NUM> and the inner body <NUM> of a drug delivery device <NUM> according to <FIG>. The indicator <NUM> comprises a first feedback element <NUM>, which is configured as a resilient arm <NUM>. The first feedback element <NUM> extends along a circumferential direction of the indicator <NUM>. The feedback feature <NUM>, in particular the resilient arm <NUM>, is arranged at a distal end of the indicator <NUM>. A thread <NUM>, which is configured to interact with the feedback feature <NUM>, is formed on the inner body <NUM>. A second feedback element <NUM> is formed in the thread <NUM>. The second feedback element <NUM> is configured as a step <NUM> in the thread <NUM>. At the end of a dispense operation, the resilient arm <NUM> passes over the step <NUM>. When the resilient arm <NUM> passes over the step <NUM>, it is preloaded in an axial direction. In particular, the resilient arm <NUM> is preloaded in a direction towards the proximal end of the device <NUM>. This preload could be retained throughout the travel of the indicator <NUM>. Alternatively, the thread pitch could alter such that the resilient arm <NUM> is preloaded near to the end of the dispense operation. As a result of this preload, the resilient arm <NUM> accelerates rapidly as it drops off the step <NUM>. Thereby, the resilient arm <NUM> strikes the thread wall <NUM> near the bottom of the step <NUM>. Thereby, and audible and/or tactile signal is created, which indicates the end of a dispense operation to a user. <FIG> shows a section of the inner body <NUM> showing the step <NUM> in the thread <NUM> in more detail.

<FIG> shows the actuator <NUM>, the indicator <NUM> and the inner body <NUM> of a drug delivery device <NUM> according to <FIG>. The embodiment according to <FIG> is similar to the embodiment shown in <FIG>. The indicator <NUM> also comprises a first feedback element <NUM> comprising a resilient arm <NUM>, which is configured to interact with a thread <NUM> formed on the inner body <NUM>. In the embodiment shown in <FIG>, the resilient arm <NUM> is configured to be preloaded radially outwards by the floor of the thread <NUM>. This preload could be retained throughout the travel of the indicator <NUM>. Alternatively, the preload could be generated when the indicator <NUM> is approaching its end of dispense position. In particular, the floor of the thread <NUM> could be raised such that the resilient arm <NUM> is preloaded near the end of the dispense operation. In the embodiment shown in <FIG>, the second feedback element <NUM>, or the step <NUM>, respectively, is radial, causing the resilient arm <NUM> to accelerate radially inwards and hit the inner body <NUM>.

Claim 1:
An assembly for a drug delivery device (<NUM>), the assembly (<NUM>) comprising a feedback feature (<NUM>) being configured to indicate an end of a dispense operation to a user by giving and audible and/or tactile feedback, the assembly comprising an actuator (<NUM>) which is configured to be operated in order to dispense a dose, and wherein the feedback feature (<NUM>) creates a feedback when the actuator (<NUM>) reaches an end position at the end of a dispense operation, wherein the assembly comprises a rotation member (<NUM>) which is configured to rotate during the dispense of a dose, wherein the feedback feature (<NUM>) comprises a first feedback element (<NUM>) which is located at the rotation member (<NUM>).