A subsassembly of a medicament delivery device for providing plunger motion

Abstract

The present disclosure generally relates to medicament delivery devices (1), and particularly concerns a subassembly (48) for proving a plunger rod (26) motion.

Description

[0001] A SUBSASSEMBLY OF A MEDICAMENT DELIVERY DEVICE FOR PROVIDING PLUNGER MOTION

[0002] TECHNICAL FIELD

[0003] The present disclosure generally relates to medicament delivery devices, and particularly concerns a subassembly for providing a plunger motion.

[0004] BACKGROUND

[0005] A number of medical conditions require injections. These days, a number of different injection devices exist, including various types of pen injectors, autoinjectors and infusion devices for large volume injections. Although many of these devices have enabled major improvements in the management of a number of medical conditions, various limitations do still exist in the current technology. In considering these problems, the applicant has appreciated that various developments could be made to help improve the medicament delivery devices on the market today, for example concerning plunger motion for medicament injection which motion is often caused by interaction with a relatively complex rotator.

[0006] SUMMARY

[0007] An object of the present disclosure is to provide a subassembly for a medicament delivery device, which solves, or at least mitigates problems of the prior art.

[0008] According to a first aspect of the present disclosure, there is provided a subassembly of a medicament delivery device, which medicament delivery device extends from a proximal end adapted to face an injection site, to a distal end, along a longitudinal axis, the subassembly comprising: a plunger rod having a longitudinal axis, the plunger rod being axially biased in a proximal direction along the longitudinal axis, the plunger rod comprising a radially outwards extending pin on an exterior surface of the plunger rod, a delivery member cover configured to move along the longitudinal axis, a shield link axially biased in the proximal direction and being configured to engage with the delivery member cover, such that axial movement of the delivery member cover causes corresponding axial movement of the shield link, the shield link being concentrically arranged with and radially outside the plunger rod and, comprising a first radially inwards extending protrusion each having an inclined surface with respect to the longitudinal axis, a cartridge housing comprising a curved guiding element extending in the distal direction and is arranged radially outside the plunger rod and radially inside the shield link, the curved guiding element comprising a set of position surfaces facing in the distal direction and that are located at different axial positions on the cartridge housing, wherein the pin of the plunger rod interacts with the first inwards extending protrusion of the shield link when the delivery member cover is moved in the proximal direction from a first axial position to a second axial position, causing an axial rotation of the plunger rod such that the pin disengages from a first position surface and moves in the proximal direction to a second position surface.

[0009] Embodiments of the present disclosure advantageously provides for moving the plunger rod to different axial positions when the delivery member cover moves along the longitudinal axis without the need for a rotator. In other words, the plunger rod can reach its different axial positions required for an injection by the interaction between the pin of the plunger rod and the inwards extending protrusions of the shield link. Once the plunger rod has rotated as a result of the interaction, the pin lands on a new position surface to hold the plunger rod in the new position, e.g., the second or further position.

[0010] The present disclosure provides for a subassembly that provides the required motion and locking of the plunger rod, without the need for a rotator, which reduces the complexity of the subassembly and consequently of a device comprising the subassembly.

[0011] 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 components 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.

[0012] Further, the term “longitudinal”, “longitudinally”, “axially” or “axial” refer to a direction extending from the proximal end to the distal end, typically along the device or components thereof in the direction of the longest extension of the device and / or component.

[0013] Similarly, the terms “transverse”, “transversal” and “transversally” refer to a direction generally perpendicular to the longitudinal direction.

[0014] Further, the terms “circumference”, “circumferential”, “circumferentially” refer to a circumference or a circumferential direction 301 relative to an axis 102, typically a central axis extending in the direction of the longest extension of the device and / or component. Similarly, “radial” or “radially” refer to a direction 302 extending radially relative to the axis, and “rotation”, “rotational” and “rotationally” refer to rotation relative to the axis.

[0015] According to one embodiment, the shield link may comprise a second radially inwards extending protrusion and the pin of the plunger rod may interact with the second radially inwards extending protrusion of the shield link when the delivery member cover is moved further in the proximal direction to a third axial position, causing an axial rotation of the plunger rod such that the pin disengages from the second position surface and moves in the proximal direction to a third position surface. The motion of the plunger rod when the pin moves to the third position surface may advantageously correspond to a priming step where the plunger rod exerts an initial pressure on a medicament container in the cartridge housing. According to one embodiment, the second radially inwards extending protrusion may be located more distally compared to the first inwards extending protrusion.

[0016] According to one embodiment, the shield link may comprise a third radially inwards extending protrusion and the pin of the plunger rod may interact with a third radially inwards extending protrusion of the shield link when the delivery member cover is moved in the distal direction to a fourth axial position, causing an axial rotation of the plunger rod such that the pin disengages from the third position surface and moves in the proximal direction to a fourth position surface. Advantageously, the motion of the plunger rod when the pin disengages from the third position surface and moves in the proximal direction to a fourth position surface may cause the plunger rod to compress a medicament container in the cartridge housing. Thus, the motion of the plunger rod when the pin disengages from the third position surface and moves in the proximal direction to the fourth position surface corresponds to an injection event. The motion of the delivery member cover in the distal direction exposes a medicament delivery member.

[0017] According to one embodiment, the third inwards extending protrusion may be located more distally than the first and the second inwards extending protrusions.

[0018] According to one embodiment, the shield link may comprise a fourth radially inwards extending protrusion comprising a proximally facing inclined surface and a distally facing surface.

[0019] According to one embodiment, the fourth radially inwards extending protrusion may be proximally located with respect to the third radially inwards extending protrusion.

[0020] According to one embodiment, wherein, when the pin is at the fourth position surface, the fourth radially inwards extending lock protrusion may be directly distally located with respect to the pin, wherein an axial distal motion of the shield link may cause the pin to reach interact with the proximally facing inclined surface of the fourth radially inwards extending protrusion, flex and reach the distally facing surface of the fourth radially inwards extending protrusion, which to prevents the shield link from moving distally. Thus, the pin is in a locking position where the delivery member cover is prevented, by the pin, to move distally and expose the medicament delivery member. In this way, sharp injury by the medicament delivery member can be prevented.

[0021] According to one embodiment, the third radially inwards extending protrusion may be oppositely inclined to the first radially inwards extending protrusion and second radially inwards extending protrusions of the needle shield link.

[0022] According to one embodiment, the pin of the plunger rod may reach radially outside the curved guiding element. This facilitates reliable physical contact between the pin and the position surfaces of the guiding element but also between the pin and the inwards extending protrusions of the shield link.

[0023] According to one embodiment, the curved guiding element maybe a sleeve having at least one cut out that defines the set of position surfaces. Hereby, a simple yet robust way of providing the set of position surfaces is provided.

[0024] According to one embodiment, the subassembly may comprise an activation member configured to move from a first activation member position to a second activation member position, wherein in the first activation member position the activation member engages with the needle shield link, preventing the needle shield link to move in the proximal direction, wherein the activation member is configured to disengage from the needle shield link when the activation member is moved to the second activation member position, causing the plunger rod to move axially in the proximal direction and the pin to reach the second position surface.

[0025] According to one embodiment, the activation member may be configured to move from the first activation member position to the second activation member position by rotation. There is further provided a medicament delivery device comprising the subassembly according to any one of the herein disclosed embodiments.

[0026] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / an / the member, apparatus, component, means, etc.” are to be interpreted openly as referring to at least one instance of the member, apparatus, component, means, etc., unless explicitly stated otherwise.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The specific embodiments of the inventive concept will now be described, by way of example, with reference to the accompanying drawings, in which:

[0029] Fig. 1 is a perspective view of a medicament delivery device according to embodiments of the present disclosure;

[0030] Fig. 2 is a cross-section of a medicament delivery device according to embodiments of the present disclosure;

[0031] Fig. 3 is a perspective view of a plunger rod according to embodiments of the present disclosure;

[0032] Fig. 4 is a cross-section of a subassembly according to embodiments of the present disclosure;

[0033] Fig. 5A is a perspective view of a shield link according to embodiments of the present disclosure;

[0034] Fig. 5B is a cross-section of a shield link according to embodiments of the present disclosure;

[0035] Fig. 5C is a cross-section of a shield link according to embodiments of the present disclosure;

[0036] Fig. 6A is a perspective view of a cartridge housing according to embodiments of the present disclosure Fig. 6B is a cross-section of a cartridge housing according to embodiments of the present disclosure;

[0037] Fig. 7 illustrates a sequence of pin motion as the shield link moves proximally;

[0038] Fig. 8 illustrates a sequence of pin motion as the shield link moves further proximally;

[0039] Fig. 9 illustrates a sequence of pin motion as the shield link moves distally; and

[0040] Fig. io is a cross-section of the subassembly in a locked state

[0041] DETAILED DESCRIPTION

[0042] The inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplifying embodiments are shown. The inventive concept may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Like numbers refer to like members throughout the description.

[0043] Fig. i shows an example of a medicament delivery device i such as an autoinjector according to embodiments of the present disclosure. The medicament delivery device 1 is configured to expel medicament from a medicament container via a medicament delivery member such as a needle, to a user at a dose delivery site. The medicament delivery device i extends from a proximal end la to a distal end ib relative to the axis 102.

[0044] The medicament delivery device 1 comprises a housing 3 with a window 4.

[0045] The housing 3 has a proximal end 3a and a distal end 3b. A delivery member cover 6 is configured to cover a needle and extends out from the proximal end 3a of the housing 3. A cap 7 is arranged to initially protect the needle inside the delivery member cover 6.

[0046] A medicament container is placed inside the housing 3 from which medicament is expelled under the action of a spring-loaded plunger rod.

[0047] At the distal end ib is an activation grip 5 arranged which maybe rotated to unlock the device 1 prior to usage.

[0048] Fig. 2 is a cross-section of the medicament delivery device 1 which comprises the delivery member cover 6 that is engaged with a shield link 8 by an interlock 10. The interlock 10 is configured so that axial motion of the delivery member cover 6 and the shield link 8 is linked. Thus, axial movement of the delivery member cover 6 causes corresponding axial movement of the shield link 8. In this this embodiment, the shield link 8 comprises an outward extending protrusion 12 that snaps into a cavity or hole 14 in the delivery member cover 6. Furthermore, a proximal end surface 18 of the shield link 8 abuts against a distally facing surface 16 of the delivery member cover 6.

[0049] The shield link 8 is axially biased by a spring 20 that is arranged between an outward extending protrusion 22 of the shield link 8 and a proximally facing surface 24 of the housing 3 at the distal end ib. The spring 20 is arranged concentrically with and outside the shield link 8.

[0050] The medicament delivery device 1 further comprises a plunger rod 26 having a longitudinal axis. The plunger rod 26 is axially biased in the proximal direction along the longitudinal axis 102 by a plunger rod spring 28 arranged concentrically with and inside the plunger rod 26.

[0051] The plunger rod 26 is configured to push, under the influence of the plunger rod spring 28, on a stopper 30 inside a medicament container 32 accommodated in a cartridge housing 34. This causes the medicament to be expelled through a medicament delivery member such as a needle 36 at an injection site. The medicament delivery device 1 further comprises an activation member 38. The activation member 38 is linked with the activation handle 5, so that when the activation handle 5 is rotated about the axis 102, the activation member 38 also rotates in the same direction. Prior to the rotation of the activation member 38, the shield link 8 is engaged with the activation member 38. For this, the activation member 38 comprises at least one radially outwards extending protrusion 40 that abuts on the proximal side 42 of a corresponding inward protrusion 44 of the shield link 8, better seen in fig. 4. Rotation of the activation member 38 causes the protrusion 40 of the activation member 38 and the inward protrusion 44 of the shield link 8 to loose contact whereby the shield link 8 and thereby also the delivery member cover 6 are released.

[0052] Fig. 3 is a perspective view of a plunger rod 26. The plunger rod 26 comprises a radially outwards extending pin 48 on an exterior surface 50 of the plunger rod 26.

[0053] Fig. 4 is a cross-section of a subassembly 46 according to embodiments of the present disclosure. The subassembly 46 comprises the plunger rod 26, the delivery cover member 6, the shield link 8, and the cartridge housing 34.

[0054] The plunger rod 26 comprises the radially outwards extending pin 48 on the exterior surface 50 of the plunger rod. The protrusion 48 extends towards a radially inwards facing surface 52 of the shield link 8.

[0055] The shield link 8 is concentrically arranged with and radially outside the plunger rod 26 and comprises radially inwards extending protrusions 54, 56, 58, 6owhich are better seen in fig. 5B.

[0056] Fig 5A is a perspective view of the shield link 8 where the protrusion 12 for the interlock 10 with the delivery cover member is shown, as well as the outward extending protrusion 22 that support the spring 20 discussed in relation to fig. 2. Furthermore, the shield link 8 comprises the radially inwards extending protrusions 54, 56, 60 on the radially inwards facing surface 52. Figs. 5B-C are cross-sections of the shield link 8 where the radially inwards extending protrusions 54, 56, 58, 60 on the radially inwards facing surface 52 are illustrated.

[0057] Each of the protrusions 54, 56, 58, 6ocomprises a proximally facing surface 54a, 56a, 58a, 6oaand a distally facing surface 54b, 56b, 58b, 60b. The proximally facing surfaces 54a, 56a, 58a and the distally facing surfaces 54b, 56b, 58bare inclined with respect to the longitudinal axis 102.

[0058] Fig. 6A is a perspective view of the cartridge housing 34 and fig. 6B illustrates a cross-section of the cartridge housing 34. The cartridge housing 34 comprises a curved guiding element 64 extending in the distal direction. The curved guiding element 64, also shown in fig. 3, is arranged radially outside the plunger rod 26 and radially inside the shield link 8. The pin 48 of the plunger rod 26 preferably reaches radially outside the curved guiding element 64. Further, the pin 48 reaches sufficiently radially outward to reach the protrusions 54, 56, 58, 60 of the shield link 8.

[0059] The cartridge housing 34 comprising a set of position surfaces 66, 68, 70, 72 facing in the distal direction and that are located at different axial positions along axis 102.

[0060] The curved guiding element 64 may be a sleeve having at least one cut out that defines at least the position surfaces 66, 68, 70. The position surfaces maybe parallel with each other. The curved guiding element 64 maybe a partial sleeve, that is, that does not cover the entire circumference of the otherwise cylindrical shape of the cartridge housing 34.

[0061] Fig. 7 illustrates a sequence of pin 48 motion with respect to the curved guiding element 64 of the cartridge housing 34 when the delivery member cover 6 is initially released by the activation member 38. This release causes the shield link 8 to move proximally as indicated by direction arrow 74.

[0062] When the shield link 8, and the delivery member cover 6 moves proximally from a first axial position to a second axial position, the pin 48 of the plunger rod interacts with a first inwards extending protrusion 54 of the shield link 8. The pin 48 interacts with the inclined proximally facing surface 54a of the first inwards extending protrusion 54 of the shield link 8. Due to the inclination of the surface 54a, the pin 48 is pushed towards the side at which the surface 54a faces, here the pin 48 is moved to the left which causes an axial rotation of the plunger rod 26 so that the pin 48 eventually reaches outside the first position surface 66 and is thus disengaged from the first position surface 66. The plunger rod 26 is axially biased by the plunger rod spring 28, thus, once the pin loses contact with the first position surface 66, the spring 28 causes the plunger 26 to move proximally until the pin 48 reaches the second position surface 68. The positioning of the pin 48 on the second position surface 68 prevents further proximal motion of the plunger rod 26 with respect to the cartridge housing 34.

[0063] Fig. 8 illustrates a sequence of pin 48 motion with respect to the curved guiding element 64 of the cartridge housing 34 when the delivery member cover 6 is moved further proximally to a third axial position. This motion causes the shield link 8 to move further proximally as indicated by direction arrow 74. This step may be due to removal of the cap 7 which moves the delivery member cover 6 proximally to cover the needle 36 to prevent sharp injury. During this step a priming action of the device 1 occurs which means that the plunger rod 26 exerts an initial force on the medicament in the medicament container 32 via the stopper 30 to e.g., expel air from the medicament container 32.

[0064] The plunger rod pin 48 is initially in contact with the second position surface 68 as described with reference to fig. 6. When the shield link 8 moves further in the proximal direction 74, the pin 48 of the plunger rod 26 interacts with a second inwards extending protrusion 56 of the shield link 8. The pin 48 interacts with the inclined proximally facing surface 56a. The surface 56a is inclined in the same direction as the surface 54a of the first inwards extending protrusion 54 of the shield link 8. Due to the inclination of the surface 56a, the pin 48 is pushed towards the side at which the surface 56a faces. In fig. 8, the pin 48 is moved to the left which causes an axial rotation of the plunger rod 26. Due to the rotation of the plunger rod 26, the pin 48 eventually reaches outside the second position surface 68 and is thus disengaged from the second position surface 68. As above, the plunger rod 26 is axially biased by the plunger rod spring 28, thus, once the pin 48 loses contact with the second position surface 68, the spring 28 cause the plunger 26 to move proximally until the pin 48 reaches the third position surface 70. The positioning of the pin 48 on the third position surface 70 prevents further proximal motion of the plunger rod 26 with respect to the cartridge housing 34.

[0065] The shield link 8 moves proximally during these two first steps, and to allow sequentially motion of the plunger rod. The second inwards extending protrusion 56 is located more distally compared to the first inwards extending protrusion 54 of the shield link 8. Thus, the motion of the plunger rod 26 during the first step cause the pin 48 to move axially to a location that is proximal in relation to the second inwards extending protrusion 56. When the pin 48 rests on the second position surface 68, the pin 48 is proximally located in relation to the second inwards extending protrusion 56.

[0066] Turning to fig. 9 where the shield link 8 is moved distally indicated by arrow 76. The distal motion 76 is due to a distal motion of the delivery member cover 6 from its extended position where it covers the needle, to a withdrawn position where the needle is exposed. The delivery member cover 6 is moved to a fourth axial position. This may be due to the device 1 being compressed against the skin of a user for an injection event.

[0067] During the distal motion 76 of the shield link 8, the pin 48 which initially is at the third position surface 70 interacts with the third inwards extending protrusion 58 of the shield link 8 when the delivery member cover 6 is moved in the distal direction to the fourth axial position. When the pin 48 rests on the third position surface 70, it is distally located with respect to the third inwards extending protrusion 58 of the shield link 8. That is, there is sufficient space between the second inwards extending protrusion 56 and the third inwards extending protrusion 58 for the pin to travel to a position distal of the third inwards extending protrusion 58 when the pin 48 moves from the second position surface 68 to the third position surface 70.

[0068] The distal motion 76 of the shield link 8 causes the pin 48 to interact with the distally facing surface 58b of the third inwards extending protrusion 58.

[0069] The distally facing surface 58b is inclined which causes the pin to be pushed to the left in fig. 9, whereby an axial rotation of the plunger rod 26 is caused such that the pin 48 disengages from the third position surface 70 and moves in the proximal direction with respect to the cartridge housing 34 to a fourth position surface 72. The third inwards extending protrusion 58 is located more distally than the first 54 and the second 56 inwards extending protrusions. Furthermore, the distal surface 58b of the third inwards extending protrusion 58 is oppositely inclined to surface 54a of the first 54 inwards extending protrusions and to the surface 56a of the second 56 inwards extending protrusions of the shield link 8.

[0070] The motion of the plunger rod 26 when the pin 48 disengages from the third position surface 70 and moves in the proximal direction towards the fourth position surface 72 causes the plunger rod 26 to compress the medicament container 32 in the cartridge housing 34 when injection occurs.

[0071] The shield link 8 comprises the fourth inwards extending protrusion 60 which serves as a lock element 60. The lock element 60 has a proximally facing inclined surface 60a and a distally facing surface 60b. The lock element 60 is proximally located with respect to the third inwards extending protrusion 58.

[0072] The rotation of the plunger rod 26 cause by interaction between the pin 48 and the third inwards extending protrusion 58 cause the pin to reach the fourth position surface 72 which is located directly under, or directly proximal to, the lock element 60. In this position, the pin 48 faces the proximally facing inclined surface 60a of the lock element 60. Turning to fig io which illustrates a locked state of the subassembly 46. After an injection, the delivery member cover moves to its extended position to again cover the needle. This causes the shield link 8 to move proximally. Thus, the pin 48 approaches and interacts with the inclined surface 60a of the lock element 60. The pin 48 flexes due to the interaction with the inclined surface 60a so that it reaches distally of the lock element 60 and thus faces its distally facing surface 60b. Alternatively, the lock element 60 flexes instead of the pin 48.

[0073] A normal axis of the distally facing surface 60b maybe parallel with the longitudinal axis 102, or is inclined so that the pin 48 cannot escape from being distal the distally facing surface 60b if the shield link 8 is moved distally. In other words, when the pin 48 is at the fourth position surface 72, with the radially inwards extending lock element 60 proximally located with respect to the pin 48, the delivery member cover 6 is locked and cannot move distally and expose the needle 36. The pin 48 comprises a distally facing inclined surface 48b which interacts with the inclined surface 60a of the protrusion 60 to facilitate the flexing of the pin 48. Further, the planar proximally facing surface 48a of the pin 48 preferable lay flat against the planar distally facing surface 60b of the protrusion 60. The pin 48 and the lock element 60 constitute a snap lock between the shield link 8 and the plunger rod 26.

[0074] Embodiments of the present disclosure maybe applied to various medicament delivery devices. In one possible implementation, the medicament delivery maybe an autoinjector.

[0075] A medicament delivery device (such as an autoinjector) may generally include various other components. For example, a sensor unit which may recognize medicament delivery events, such as the needle inserted into an attachment portion of e.g., a pad, injection started, and medicament delivery operation ends, a memory unit which is configured to store the recorded data during the medicament delivery operation, a connectivity unit configured to transmit the stored data to a smart device or the network directly, a processing unit configured to control the entire system and processes the data before transmitting it, and / or user interface units that are configured to provide feedback to the patient, such as status LEDs, haptic, and / or audio feedback.

[0076] When the medicament delivery device is placed into the attachment portion, the sensors inside of the pad are configured to recognize the event and give feedback to the patient via haptic / visual or audio elements.

[0077] When the medicament delivery finishes, the sensors are configured to recognize the event and give feedback to the patient again. Further, the collected data is stored in the memory unit and may be transmitted to the smart device / network via the connectivity unit after the medicament delivery event finishes.

[0078] The sensor can be one of or the combination of the following: a mechanical switch, a Hall-effect sensor, an accelerometer.

[0079] The mechanical switch, hall-effect sensor, or accelerometer can be used for detection of the insertion of a needle into an injection port.

[0080] The accelerometer can be used for detecting medicament delivery events.

[0081] Possible wireless communication methods include Bluetooth and Cellular Networks.

[0082] Bluetooth connectivity requires a smart device to transmit the stored data to the network and it requires a pairing action between the pad and the smart device before being able to use the supporting pad in case of 2-way connection. But it’s a cheaper alternative and it requires less space on PCB. A i-way connection does not require pairing.

[0083] The cellular network does not require any pairing process, it can be used as a plug-n-play device, no prior setup is needed, but it’s more expensive and it requires more space on PCB. Depending on the requirements of the product any of those two technologies can be used.

[0084] Such processing units or processing circuitry may comprise a logic circuit or control unit including a microprocessor, microcontroller, programmable digital signal processor or another programmable device. The processing circuitry may also, or instead, each include an application specific integrated circuit, a programmable gate array or programmable array logic, a programmable logic device, or a digital signal processor. Where the processing circuitry includes a programmable device such as the microprocessor, microcontroller or programmable digital signal processor mentioned above, the processor may further include computer executable code that controls operation of the programmable device.

[0085] The medicament delivery devices described herein can be used for the treatment and / or prophylaxis of one or more of many different types of disorders. Exemplary disorders include, but are not limited to: rheumatoid arthritis, inflammatory bowel diseases (e.g. Crohn’s disease and ulcerative colitis), hypercholesterolaemia, diabetes (e.g. type 2 diabetes), psoriasis, migraines, multiple sclerosis, anaemia, lupus, atopic dermatitis, asthma, nasal polyps, acute hypoglycaemia, obesity, anaphylaxis and allergies. Exemplary types of drugs that could be included in the medicament delivery devices described herein include, but are not limited to, antibodies, proteins, fusion proteins, peptibodies, polypeptides, pegylated proteins, protein fragments, protein analogues, protein variants, protein precursors, and / or protein derivatives. Exemplary drugs that could be included in the medicament delivery devices described herein include, but are not limited to (with non-limiting examples of relevant disorders in brackets): etanercept (rheumatoid arthritis, inflammatory bowel diseases (e.g. Crohn’s disease and ulcerative colitis)), evolocumab (hypercholesterolaemia), exenatide (type 2 diabetes), secukinumab (psoriasis), erenumab (migraines), alirocumab (rheumatoid arthritis), methotrexate (amethopterin) (rheumatoid arthritis), tocilizumab (rheumatoid arthritis), interferon beta-ia (multiple sclerosis), sumatriptan (migraines), adalimumab (rheumatoid arthritis), darbepoetin alfa (anaemia), belimumab (lupus), peginterferon beta-ia' (multiple sclerosis), sarilumab (rheumatoid arthritis), semaglutide (type 2 diabetes, obesity), dupilumab (atopic dermatitis, asthma, nasal polyps, allergies), glucagon (acute hypoglycaemia), epinephrine (anaphylaxis), insulin (diabetes), atropine and vedolizumab (inflammatory bowel diseases (e.g. Crohn’s disease and ulcerative colitis)). Pharmaceutical formulations including, but not limited to, any drug described herein are also contemplated for use in the medicament delivery devices described herein, for example pharmaceutical formulations comprising a drug as listed herein (or a pharmaceutically acceptable salt of the drug) and a pharmaceutically acceptable carrier. Pharmaceutical formulations comprising a drug as listed herein (or a pharmaceutically acceptable salt of the drug) may include one or more other active ingredients, or maybe the only active ingredient present.

[0086] The inventive concept has mainly been described above with reference to a few examples. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended claims. In particular, whilst various distinct embodiments have been described with reference to the drawings, it will be appreciated that components of these distinct embodiments may be interchanged to provide further embodiments.

Claims

CLAIMS i. A subassembly (46) for a medicament delivery device (1), which medicament delivery device (1) extends from a proximal end (la) adapted to face an injection site, to a distal end (ib), along a longitudinal axis (102), the subassembly (46) comprising:- a plunger rod (26) having a longitudinal axis, the plunger rod being axially biased in a proximal direction along the longitudinal axis, the plunger rod (26) comprising a radially outwards extending pin (48) on an exterior surface (50) of the plunger rod (26),- a delivery member cover (6) configured to move along the longitudinal axis,- a shield link (8) axially biased in the proximal direction and being configured to engage with the delivery member cover (6), such that axial movement of the delivery member cover (6) causes corresponding axial movement of the shield link (8), the shield link (8) being concentrically arranged with and radially outside the plunger rod (26) and comprising a first radially inwards extending protrusion (54) having an inclined surface with respect to the longitudinal axis,- a cartridge housing (34) comprising a curved guiding element (64) extending in the distal direction and arranged radially outside the plunger rod (26) and radially inside the shield link (8), the curved guiding element (64) comprising a set of position surfaces (66, 68, 70, 72) facing in the distal direction and that are located at different axial positions on the cartridge housing (34), wherein the pin (48) of the plunger rod (26) interacts with the first radially inwards extending protrusion (54) when the delivery member cover (6) is moved in the proximal direction from a first axial position to a second axial position, causing an axial rotation of the plunger rod (26) such that thepin (48) disengages from a first position surface (66) and moves in the proximal direction to a second position surface (68).

2. The subassembly (46) of claim 1, wherein the shield link (8) comprises a second radially inwards extending protrusion (56) and the pin (48) of the plunger rod (26) interacts with the second radially inwards extending protrusion (56) when the delivery member cover (6) is moved further in the proximal direction to a third axial position, causing an axial rotation of the plunger rod (26) such that the pin (48) disengages from the second position surface (68) and moves in the proximal direction to a third position surface (70).

3. The subassembly (46) of claim 2, wherein the second radially inwards extending protrusion (56) is located more distally compared to the first inwards extending protrusion (54).

4. The subassembly (46) of any one of claims 2-3, wherein the shield link (8) comprises a third radially inwards extending protrusion (58) and the pin (48) of the plunger rod (26) interacts with the third radially inwards extending protrusion (58) when the delivery member cover (6) is moved in the distal direction to a fourth axial position, causing an axial rotation of the plunger rod (26) such that the pin (48) disengages from the third position surface (70) and moves in the proximal direction to a fourth position surface (72).

5. The subassembly of claim 4, wherein the third radially inwards extending protrusion (58) is located more distally than the first radially inwards extending protrusion (54) and the second radially inwards extending protrusion (56).

6. The subassembly (46) of any one of claims 4-5, wherein the motion of the plunger rod (26) when the pin (48) disengages from the third position surface (70) and moves in the proximal direction to the fourth position surface (72) causes the plunger rod (26) to compress a medicament container (30) in the cartridge housing (34).

7. The subassembly (46) of any one of claims 4-6, wherein the shield link (8) comprises a fourth radially inwards extending protrusion (60) comprising a proximally facing inclined surface (60a) and a distally facing surface (60b).

8. The subassembly (46) of claim 7, wherein the fourth radially inwards extending protrusion (62) is proximally located with respect to the third radially inwards extending protrusion (58).

9. The subassembly (46) of any one of claims 7-8, wherein, when the pin (48) is at the fourth position surface (72), the radially inwards extending lock protrusion (60) is directly distally located with respect to the pin (48), wherein an axial distal motion of the shield link cause the pin to reach interact with the proximally facing inclined surface (60a) of the fourth radially inwards extending protrusion (60), flex and reach the distally facing surface (60b) of the fourth radially inwards extending protrusion (60), which to prevents the shield link from moving distally.

10. The subassembly (46) of any one of claims 4-9, wherein the third radially inwards extending protrusion (58) is oppositely inclined to the first radially inwards extending protrusion (54) and second radially inwards extending protrusion (56).

11. The subassembly (46) according to any one of the preceding claims, wherein the pin (48) of the plunger rod (26) reaches radially outside the curved guiding element (64).

12. The subassembly (46) according to any one of the preceding claims, wherein the curved guiding element (64) is a sleeve having at least one cut out that defines at least one of the set of position surfaces (66, 68, 70, 72).

13. The subassembly (46) according to any of the preceding claims, comprising an activation member (38) configured to move from a first activation member position to a second activation member position, wherein in the first activation member position the activation member (38) engageswith the shield link (8), preventing the shield link (8) from moving in the proximal direction, wherein the activation member (38) is configured to disengage from the shield link (8) when the activation member (38) is moved to the second activation member position, causing the plunger rod (26) to move axially in the proximal direction and the pin (48) to reach the second position surface (68).

14. The subassembly (46) according claim 13, wherein the activation member (38) is configured to move from the first activation member position to the second activation member position by rotation.

15. A medicament delivery device (1) comprising the subassembly (46) according to any one of the preceding claims.

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