CN118678978A - Feedback subassembly for a drug delivery device - Google Patents

Abstract

A subassembly for a drug delivery device (10) is described, the subassembly extending from a proximal end to a distal end in a longitudinal direction (13) along a longitudinal axis (12). The subassembly includes a housing (30, 62) and a plunger rod (70). The plunger rod (70) is at least partially arranged in the housing; and the plunger rod (70) includes a first surface (78) facing the proximal end, and the components of the subassembly other than the plunger rod (70) include a second surface (68) facing the distal end, and the first surface (78) and the second surface (68) are arranged so that when the plunger rod (70) moves toward the proximal end relative to the component during use of the drug delivery device, the first surface (78) and the second surface (68) engage to rotate the plunger rod (70) relative to the component, and then disengage so that the plunger rod (70) rotates back relative to the component. The subassembly includes a torsion spring (90) attached to the plunger rod (70) at one end and to the component at the other end.

Description

Feedback subassembly for a drug delivery device

Technical Field

The present invention relates to a subassembly for a medicament delivery device, in particular a subassembly having a housing and a plunger rod.

Background

Some medicament delivery devices provide feedback to the user during operation, such as with the U-shaped stent described in WO 2011/123024. While such systems may provide effective feedback, applicants have appreciated that it may be useful to provide an alternative feedback mechanism that potentially provides various advantages over existing feedback mechanisms.

Disclosure of Invention

Reference should now be made to the appended claims.

In the present disclosure, when the term "distal direction" is used, this means pointing away from the dose delivery site during use of the medicament delivery device. When the term "distal portion/distal end" is used, this refers to the portion/end of the delivery device or the portion/end of the member of the delivery device that is positioned furthest away from the dose delivery site during use of the medicament delivery device. Accordingly, when the term "proximal direction" is used, this refers to pointing in a direction towards the dose delivery site during use of the medicament delivery device. When the term "proximal portion/proximal end" is used, this refers to the portion/end of the delivery device or the portion/end of the member of the delivery device that is positioned closest to the dose delivery site during use of the medicament delivery device.

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

Similarly, the terms "transverse", "transverse" and "transversely" refer to directions substantially perpendicular to the longitudinal direction.

One aspect relates to a subassembly for a medicament delivery device extending in a longitudinal direction along a longitudinal axis from a proximal end to a distal end, the subassembly comprising: a housing; and a plunger rod at least partially disposed within the housing; wherein the plunger rod comprises a first surface towards the proximal end and the parts of the subassembly other than the plunger rod comprises a second surface towards the distal end, the first and second surfaces being arranged such that, when the plunger rod is moved towards the proximal end relative to the parts during use of the medicament delivery device, the first and second surfaces engage to rotate the plunger rod relative to the parts and then the first and second surfaces disengage such that the plunger rod rotates back relative to the parts (to create feedback), and wherein the subassembly comprises a torsion spring attached to the plunger rod at one end and to the parts at the other end. This may provide feedback to the user of the medicament delivery device, such as audible, visual or tactile feedback.

Optionally, the component is a housing. Optionally, the housing comprises a shell and a rear cover, and the rear cover comprises a second surface.

Optionally, the second surface is located on the protrusion. Optionally, the protrusion extends towards the longitudinal axis. Optionally, the first surface is located on the second protrusion. Optionally, the second protrusion extends away from the longitudinal axis.

Optionally, at least a portion of at least one of the first surface and the second surface is angled with respect to a plane perpendicular to the longitudinal axis.

Optionally, the first surface and/or the second surface comprises a surface (79) parallel to the longitudinal axis.

Optionally, at least a portion of at least one of the first surface and the second surface is angled with respect to a plane perpendicular to the longitudinal axis, the angle being between 10 degrees and 85 degrees, particularly between 30 degrees and 70 degrees, most particularly between 45 degrees and 60 degrees.

Optionally, at least a portion of the first surface is angled with respect to a plane perpendicular to the longitudinal axis. Optionally, the subassembly comprises a feedback surface angled with respect to a plane perpendicular to the longitudinal axis, wherein the feedback surface is spaced apart from the distal end of the first surface in a circumferential direction with respect to the longitudinal axis. Optionally, the feedback surface is parallel to the longitudinal axis.

Optionally, at least a portion of the second surface is angled with respect to a plane perpendicular to the longitudinal axis. Optionally, the subassembly comprises a feedback surface angled with respect to a plane perpendicular to the longitudinal axis, wherein the feedback surface is spaced apart from the proximal end of the first surface in a circumferential direction with respect to the longitudinal axis. Optionally, the feedback surface is parallel to the longitudinal axis.

Optionally, the plunger rod comprises a feedback surface. Optionally, the component is rotationally locked relative to the housing.

Optionally, a spring is arranged between the plunger rod and the housing and is configured to move the plunger rod towards the proximal end during medicament delivery. Alternatively, the spring and torsion spring are the same component. Alternatively, the torsion spring is a first spring and the spring is a second spring.

One aspect relates to a medicament delivery device comprising a subassembly as described above. Optionally, the medicament delivery device is an automatic injector.

One aspect relates to a method of generating feedback in a medicament delivery device, the method comprising the following steps in the following order: moving the plunger rod in a proximal direction relative to the other member such that a proximally facing surface of the plunger rod engages a distally facing surface of the other member, thereby rotating the plunger rod in a first direction relative to the other member; further movement of the plunger rod relative to the other member in the proximal direction disengages the proximally facing surface of the plunger rod from the distally facing surface of the other member and subsequently rotates the plunger rod in the second direction, thereby generating feedback. Typically, the first direction and the second direction are opposite directions.

One aspect relates to a subassembly for a medicament delivery device extending in a longitudinal direction along a longitudinal axis from a proximal end to a distal end, the subassembly comprising: a housing; and a plunger rod at least partially disposed within the housing; wherein the plunger rod comprises a first engagement portion and the parts of the sub-assembly other than the plunger rod comprise a second engagement portion, wherein the first engagement portion and the second engagement portion are arranged such that, when the plunger rod moves relative to the parts during use of the medicament delivery device, the first engagement portion engages with the second engagement portion such that the plunger rod rotates relative to the parts, and then the first engagement portion disengages from the second engagement portion such that the plunger rod rotates back relative to the parts. Optionally, the subassembly comprises a torsion spring attached at one end to the plunger rod and at the other end to the component. Optionally, the first engagement portion includes a proximally facing surface. Optionally, the second engagement portion includes a distally facing surface. Optionally, the first engagement portion and/or the second engagement portion is a protrusion.

In general, 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 an/the element, device, component, means, device, etc. are to be interpreted openly as referring to at least one instance of the element, device, component, means, device, etc., unless explicitly stated otherwise.

Drawings

Embodiments of the present disclosure will now be described, by way of example only, with reference to the following drawings.

FIG. 1 illustrates a perspective view of components of an example subassembly.

Fig. 2 shows a close-up of the proximal end of the rear cover of the subassembly of fig. 1.

Fig. 3-6 show side views of another example subassembly at various stages during medicament delivery.

Fig. 7 shows a perspective view of the example torsion spring of fig. 3.

Fig. 8 shows a perspective view of the piston rod of the example of fig. 3.

Fig. 9 and 10 show the protrusion of the piston rod of fig. 1 and 8, respectively. Fig. 11 shows a perspective view of an example auto-injector that may include any of the sub-assemblies depicted in the previous figures.

Fig. 12 to 15 show alternative shapes of the protrusions of the plunger rod and the rear cover.

Detailed Description

Fig. 1 shows separate components of a sub-assembly for a medicament delivery device. The subassembly includes a housing (in this case, the rear cover 62), a plunger rod 70, and a torsion spring 90. The torsion spring 90 is attached at one end to the plunger rod 70 and at the other end to the rear cover 62. In this example, the distal end 91 of the torsion spring 90 is attached in the bore 66 of the rear cap 62 and the proximal end 92 of the torsion spring 90 is attached in a bore (not shown) in the plunger rod 70. Optionally, torsion spring 90 has a straight section at each end, optionally extending directly away from the axis, as shown in fig. 1; this may help attach the spring to other components (in this case, the rear cap 62 and the plunger rod 70).

The plunger rod 70 comprises a proximally facing surface (first surface) towards the proximal end and the parts of the subassembly other than the plunger rod, in this case the housing and more particularly the rear cover 62, comprise a distally facing surface (second surface) towards the distal end. In the example shown in fig. 1, the proximally facing surface is a surface 78 of a protrusion 76, wherein the protrusion extends from the outer surface of the plunger rod 70. As seen in fig. 2 (which shows a close-up of the proximal end of the rear cover 62), the distally facing surface is a surface 68 of a protrusion 67, which extends from the inner surface of the rear cover 62. Optionally, as shown in fig. 2, a second protrusion 95 may be provided on the rear cover; this may help prevent over-rotation of the plunger rod.

During use of the medicament delivery device comprising the sub-assembly, the plunger rod moves relative to the component (in this case the rear cap) causing the proximally facing surface and the distally facing surface to engage to rotate the plunger rod relative to the component, which in turn subsequently disengages such that the plunger rod rotates back relative to the component, which may produce feedback (e.g., audible, visual and/or tactile feedback).

Fig. 3-8 illustrate a second example subassembly. In this example, the protrusion 76 is of a different shape and a different shape torsion spring 90 is used, but in other respects the example is substantially the same as the example of fig. 1 and 2.

Fig. 11 shows an example of an automatic injector 10 that may include any of the sub-assemblies depicted in the figures. For reference, a longitudinal axis 12, an axial direction 13, a proximal end 14, a distal end 15, a circumferential direction 16 and a radial direction 17 are shown. The automatic injector comprises: a housing comprising a shell 30 (with optional window 32) and a rear cover 62; and a needle shield 40 (more generally, a medicament delivery member shield). Typical auto-injectors also include a power unit for driving the plunger rod. For example, the power unit may use a power source (such as a spring, a battery, or compressed gas) to provide power. The rear cover 62 may be part of a power unit and may house a power source. A medicament container such as a syringe or cartridge will be provided and a medicament delivery member such as a needle or jet injector will be provided. Although not required, the power unit will typically be locked until the device is activated for use, for example by rotating the rotator 58 shown in the drawings by the medicament delivery member sheath (e.g., needle sheath 40) or another component such as a button. A medicament delivery container carrier, such as a syringe carrier, may also be provided, however the medicament delivery container may be supported by one or more other components, such as by a housing. Although an automatic injector is described, the sub-assembly may also be used more generally with other injectors or other medicament delivery devices (including non-automatic medicament delivery devices such as pen injectors), and thus components such as the back cover, power unit, rotator, and medicament delivery member sheath are optional.

The particular structure, shape, and attachment points of the torsion springs shown in the examples are optional and may vary, e.g., the torsion springs are attached in grooves rather than holes (e.g., holes 66 in fig. 1), or by glue.

Alternatively, the spring and torsion spring of the power unit may be the same spring, or alternatively may be two separate springs. In examples where they are the same spring, energy may be stored for drug delivery by compressing the spring and energy may be stored by twisting the spring as described above to provide feedback.

The method of operation of the sub-assembly will now be described in more detail with reference to a second example sub-assembly depicted in fig. 3-8. In fig. 3, the plunger rod 70 has been released and is moving towards the proximal end of the medicament delivery device (i.e. in a proximal direction with respect to the rear cap). Since the respective surfaces 67, 76 of the plunger rod and the rear cover have not yet engaged each other, the plunger rod has not yet been rotated relative to the rear cover.

In fig. 4, the respective surfaces of the plunger rod and the rear cap have now engaged each other and the plunger rod has begun to rotate relative to the rear cap. Since the torsion spring is attached to the rear cap at one end and to the plunger rod at the other end, the torsion spring is elastically deformed by the rotation of the plunger rod with respect to the rear cap, thereby transferring some energy from the power source driving the plunger rod to the torsion spring.

In fig. 5, the plunger rod has now been rotated to its maximum extent relative to the rear cover. As the plunger rod continues to move in the proximal direction relative to the back cover, the plunger rod disengages from the back cover, which allows the energy accumulated in the torsion spring to rotate the plunger rod in the opposite direction back to the position shown in fig. 6. This rotation may be rapid, allowing feedback (in particular an audible click) to be generated due to impact with another component.

The specific structure of the engagement portion of the plunger rod and the corresponding engagement portion of the rear cover will now be discussed in more detail. In the example of the figures, two different options are given, both with a protrusion on the plunger rod and a corresponding protrusion on the rear cover. In these cases, the protrusion on the plunger rod may be considered as an engagement portion of the plunger rod and the protrusion of the rear cover may be considered as an engagement portion of the rear cover. Further alternative structures of the engagement portion will be described later.

In the first example shown in fig. 1 and 2, a protrusion 76 having the shape shown in fig. 9 is provided. The protrusion includes a surface 78 (rotating surface), a surface 79 (retaining surface), and a surface 80 (striking surface). Surface 78 is adjacent to surface 79 such that during use, surface 68 of projection 67 moves directly from abutment with surface 78 to abutment with surface 79. The other surface 80 is spaced apart from the surface 79 (the other surface being offset in the circumferential direction). This gap between surface 79 and surface 80 allows protrusion 76 to accelerate relative to protrusion 67, thereby allowing feedback (particularly audible feedback) from the impact of protrusion 67 with surface 80. Surface 78 is a proximally facing surface and is angled relative to the longitudinal axis-this angle allows projection 67 to engage projection 76 to rotate the plunger rod relative to the rear cap. The surface 79 is optional, but the inclusion of the surface 79 or varying the length of the surface 79 may be used to adjust the timing at which energy accumulated in the torsion spring is released during use of the device. The surface 79 is parallel to the longitudinal axis, but this is optional. The surface 80 is parallel to the longitudinal axis, but this is optional.

In the second example shown in fig. 3 to 8, a protrusion 76 having the shape shown in fig. 10 is provided. The protrusion 76 includes a surface 78 and a surface 79 (but slightly different in size) as shown in fig. 9. The protrusion does not include the surface 80 of fig. 9; alternatively, a surface for the projection 67 to strike may be provided on the other component. More generally, the surface for the projection 67 to strike is also optional, as the feedback may alternatively be tactile or visual, such as the projection 76 being visible through a window in the housing after the projection 76 has passed the surface 79.

Although the examples herein provide surfaces on the protrusions that engage each other, this is optional. For example, one of these surfaces may be located on the protrusion while the other surface is a wall of a groove (e.g., a spiral groove), or one or more of these surfaces may be formed by a discontinuity (such as a step).

In the example shown herein, the engagement portions (surfaces that engage each other) are located on the rear cover 62 and the plunger rod 70. The engagement portion may be located on another component, such as another portion of the housing (e.g., the housing), the syringe carrier, or the rotator, rather than on the rear cover. The rotator in the medicament delivery device is typically rotatable relative to other components, such as the housing and the plunger rod, only at certain moments during use of the medicament delivery device, and rotation is limited at other moments, e.g. during medicament delivery. Therefore, when considering the rotation state of the rotator, the rotator may be used to accommodate the engagement portion.

In the example shown herein, the plunger rod 70 is held in place within the rear cap 62 before use by the arms 64 of the rear cap 62 interacting with the apertures 75 of the plunger rod 70 (see fig. 1), but other mechanisms for holding the plunger rod in place before use may also be provided.

Various other modifications may be made to the example protrusions shown in fig. 9 and 10. For example, the protrusion of fig. 9 or the protrusion of fig. 10 may be replaced by a protrusion having a shape as shown in one of fig. 12 to 14. Also shown in this context is a projection 67 of the housing (e.g. rear cover). In fig. 12 to 14, the projection 67 of the housing is circular. In general, the protrusions 67 may have various shapes including circular, triangular, square, or irregular shapes.

In the example provided above, the projection 67 of the rear cap has a surface parallel to the longitudinal axis (surface 68) and a surface perpendicular to the longitudinal axis, and the surface 78 of the plunger rod is the only surface angled with respect to the longitudinal axis. The two engagement portions are switchable such that the projection 76 is provided on the rear cover and the projection 67 is provided on the rear cover. An example of the angled surface being located on the housing (e.g., rear cap) rather than on the plunger rod is shown in fig. 15. In this example, the angle of surface 68 is the same as the angle of surface 78 of the plunger rod in the example of fig. 12-14, but surface 68 is inclined toward the distal end rather than toward the proximal end. In this example, the protrusion 76 of the plunger rod is circular, but may be of various other shapes including triangular, square or irregular. A surface 69 (strike surface) is also optionally provided, similar to the surface 80 of the other depicted examples, but facing in a distal direction instead of a proximal direction.

It is conceivable to provide two protrusions 76 on the plunger rod and two corresponding protrusions 67 on the rear cover. Typically, the two protrusions 76 will be opposite each other with respect to the longitudinal axis and the two protrusions 67 will also be opposite each other with respect to the longitudinal axis, but this is optional and different spacings may also be used. Alternatively, one, three or more protrusions 76 may be provided, optionally equally spaced about the axis. Typically, one protrusion 67 on the rear cover is provided for each protrusion 76 on the plunger rod.

Typically, at least one of the protrusion on the rear cap and the protrusion on the plunger rod comprises a surface (such as surface 78) that is angled with respect to a plane perpendicular to the longitudinal axis, i.e. a surface that extends in a direction having an angle of more than 0 degrees and less than 90 degrees (e.g. between 10 degrees and 85 degrees) with respect to a plane perpendicular to the longitudinal axis. Preferably, the angle is between 30 and 70 degrees, or between 45 and 60 degrees. The examples of surfaces 78 shown in the figures all have a constant angle, but the angle may also vary, for example may be curved when viewed from the angle shown in fig. 9 (i.e. perpendicular to the longitudinal axis, which is behind the protrusions). As shown in fig. 14, the surface 78 may also have two sections at different angles.

In the example of fig. 3-8, the protrusion 76 includes a surface 79 perpendicular to the axis in addition to the proximally facing surface 78. The surface 79 is optional but may be used to adjust the timing of the feedback.

The particular shape of the rear cover 62 shown in the figures may vary and various other optional rear cover features are shown, such as a power unit transfer lock arm 63, a pre-actuation lock arm 64, and a syringe support arm 65, but are not described in detail as they are not directly related to providing feedback. In the depicted examples, the plunger rod is shown within the rear cap (i.e., the plunger rod is at least partially disposed within the housing-in these examples, at least partially disposed within the rear cap of the housing), the protrusion of the plunger rod extends from the outer surface of the plunger rod and the protrusion of the rear cap extends from the inner surface of the rear cap, although this could be reversed, the protrusion of the plunger rod being located on the inner surface of the plunger rod and the protrusion of the rear cap extending from the outer surface of the rear cap (e.g., from the outer surface of the tubular extension of the rear cap that extends within the distal end of the plunger rod).

In such applications, it is primarily envisaged that feedback will be provided at the beginning or end of delivery, but the timing of the feedback may be adjusted by adjusting the relative positions of the features described above. Alternatively, multiple feedback instances may be provided, for example selected from the group consisting of start of delivery feedback, end of delivery feedback, and "continuous" feedback during delivery (i.e., multiple closely spaced clicks provide multiple feedback instances). The two (or more) feedback examples may be achieved by two (or more) protrusions located at different axial positions on the plunger rod. For example, the feedback may be audible, tactile, and/or visual.

The drug delivery devices described herein may be used to treat and/or prevent one or more of many different types of diseases. Exemplary diseases include, but are not limited to: rheumatoid arthritis, inflammatory bowel disease (e.g., crohn's disease and ulcerative colitis), hypercholesterolemia, diabetes (e.g., type 2 diabetes), psoriasis, migraine, multiple sclerosis, anemia, lupus, atopic dermatitis, asthma, nasal polyps, acute hypoglycemia, obesity, allergic reactions, and allergies. Exemplary drugs that may be included in the drug delivery devices described herein include, but are not limited to (non-limiting examples of related diseases in parentheses): etanercept (rheumatoid arthritis, inflammatory bowel disease (e.g., crohn's disease and ulcerative colitis)), allo You Shan anti (hypercholesterolemia), exenatide (type 2 diabetes), secukinumab (psoriasis), exenatide You Shan anti (migraine), alcuzumab (rheumatoid arthritis), methotrexate (amethopterin) (rheumatoid arthritis), tozuelan (rheumatoid arthritis), interferon beta-ia (multiple sclerosis), sumatriptan (migraine), adalimumab (rheumatoid arthritis), dapoxetine alpha (anemia), belimumab (lupus), polyethylene glycol interferon beta-ia ' (multiple sclerosis), sha Lilu mab (rheumatoid arthritis), cable Ma Lutai (type 2 diabetes, obesity), doluzumab (atopic dermatitis, asthma, nasal polyps, allergies), glucagon (acute hypoglycemia), insulin (allergic reaction), atropine (diabetes), and polyahlamygdalin (Crohn's disease), and polyahlungin (colitis). Pharmaceutical formulations including, but not limited to, any of the drugs described herein are also contemplated for use in the drug delivery devices described herein, e.g., pharmaceutical formulations comprising a drug (or a pharmaceutically acceptable salt of a drug) and a pharmaceutically acceptable carrier as set forth herein. Pharmaceutical formulations comprising a drug (or a pharmaceutically acceptable salt of a drug) as listed herein may include one or more other active ingredients, or may be the only active ingredient present.

Various modifications to the described embodiments are possible and will occur to those skilled in the art without departing from the invention as defined by the appended claims.

Claims (15)

1. A sub-assembly for a medicament delivery device (10), the sub-assembly extending in a longitudinal direction (13) along a longitudinal axis (12) from a proximal end to a distal end, the sub-assembly comprising:

A housing (30,62); and

-A plunger rod (70) arranged at least partially within the housing;

Wherein the plunger rod (70) comprises a first surface (78) facing the proximal end and the parts of the subassembly other than the plunger rod (70) comprise a second surface (68) facing the distal end, the first surface (78) and the second surface (68) being arranged such that, during use of the medicament delivery device, when the plunger rod (70) moves relative to the parts towards the proximal end, the first surface (78) and the second surface (68) engage to rotate the plunger rod (70) relative to the parts and then the first surface and the second surface disengage such that the plunger rod (70) rotates back relative to the parts, and

Wherein the subassembly comprises a torsion spring (90) attached at one end to the plunger rod (70) and at the other end to the component.

2. The subassembly of claim 1, wherein the component is the housing (30,62).

3. The subassembly of claim 1 or2, wherein the housing comprises an outer shell (30) and a rear cover (62), and the rear cover (62) comprises the second surface (68).

4. The subassembly of any preceding claim, wherein at least a portion of at least one of the first surface (78) and the second surface (68) is angled with respect to a plane perpendicular to the longitudinal axis (12).

5. The subassembly of claim 4, wherein at least a portion of at least one of the first surface (78) and the second surface (68) is at an angle between 10 degrees and 85 degrees relative to a plane perpendicular to the longitudinal axis (12).

6. The subassembly of claim 4 or 5, wherein at least a portion of the first surface (78) is angled with respect to a plane perpendicular to the longitudinal axis (12).

7. The subassembly of claim 6, wherein the subassembly comprises a feedback surface (80) that is angled with respect to a plane perpendicular to the longitudinal axis (12), wherein the feedback surface (80) is spaced apart from a distal end of the first surface (78) in a circumferential direction (16) with respect to the longitudinal axis (12).

8. The subassembly of any of claims 4 to 7, wherein at least a portion of the second surface (68) is angled relative to a plane perpendicular to the longitudinal axis (12).

9. The subassembly of claim 8, wherein the subassembly comprises a feedback surface (80) that is angled with respect to a plane perpendicular to the longitudinal axis (12), wherein the feedback surface (80) is spaced apart from a proximal end of the first surface (78) in a circumferential direction (16) with respect to the longitudinal axis (12).

10. The subassembly of claim 7 or 9, wherein the plunger rod (70) comprises the feedback surface (80).

11. A sub-assembly according to any preceding claim, wherein the component is rotationally locked relative to the housing (30,62).

12. The subassembly of any preceding claim, wherein a spring is disposed between the plunger rod and the housing, and the spring is configured to move the plunger rod toward the proximal end during medicament delivery.

13. The subassembly of claim 12, wherein the spring and the torsion spring (90) are the same component.

14. The subassembly of claim 12, wherein the torsion spring (90) is a first spring and the spring is a second spring.

15. A medicament delivery device (10) comprising the sub-assembly of any preceding claim.