Injection monitoring module

Abstract

An injection monitoring module is adapted and configured to be removably mounted to one end of an injection pen having a body, a dose setting wheel connected to the body, and an injection actuator. The dose setting wheel is rotatable about a central longitudinal axis of the pen injection system during dose setting and is fixed without rotation during injection. The injection monitoring module includes a hollow body including a distal body portion extending around an outer surface of the injection pen body distal to the dose setting wheel, and the distal body portion includes a diameter changing device configured to change the diameter of the injection pen body when the injection monitoring module is mounted on the injection pen body. An inner diameter of a central bore of the distal body portion is dynamically changed from a first value to a second value different from the first value.

Description

Technical Field

[0001] The present invention relates generally to monitoring systems for injectable drug delivery devices, and more particularly to injection monitoring for injection pen systems. Background Art

[0002] Injection monitoring is a well-known area associated with injectable drug delivery devices, for example, in particular for infusion systems. Over time, such monitoring systems have recently been transferred to injection pen systems for delivering drugs, enabling users of such pen injection systems and health care professionals involved in the treatment and follow-up of such patients to more closely monitor their proprietary injection regimens and, in many cases, the actual doses administered in an attempt to lead to better health care outcomes. These developments have been accompanied by an increase in the associated use of software and portable communication devices such as tablet computers or smartphones, which have been programmed to receive information from and interact with the monitoring system in order to provide information to the user or health care professional either instantly or periodically via an appropriate communication unit included in the monitoring system.

[0003] For example, with respect to pen injection systems in particular, one of the challenges is to provide an easy to use, reliable and reasonably safe system that can be adapted to the various different variations of such commercially available pen injection systems, of which there are many. Previous attempts to provide such monitoring systems have generally involved adapting the body of the pen injection system by including therein the electronic components as well as one or more sensors. However, a major disadvantage of such systems is that, once all of the electronic components are integrated together, they tend to make the final product rather large and cumbersome, and therefore more difficult to use from the user's perspective. Furthermore, such improved systems tend to be very specific to a given brand or manufacturer, and therefore have little or no use for other manufacturers. Moreover, in order to overcome the problem of the bulkiness and unwieldy nature of the improved pen injection systems, there has been a trend to attempt to reduce the overall volume of the injection pen body as much as possible through miniaturization of complex electronic components, which in turn brings its own problems, particularly electromagnetic interference between the various components due to the close proximity of the circuits that provide the required or desired integrated functions. Moving the sensors in such a monitoring system farther away from sources of electromagnetic interference would only complicate matters further, potentially leading to erroneous readings or requiring additional systems to compensate for the physical separation of the sensors from other electronic components, such as microcontrollers designed to control and command the various components and manage their interactions.

[0004] The injection pen system in question is well known per se and is typically equipped with a proximally located dose setting wheel and an injection actuator, the dose setting wheel being rotatable about a central longitudinal axis of the pen injection system. The user rotates the wheel to select the dose of medication to be administered. The pen is typically mechanically or electromechanically configured to perform an injection when an injection activator is in an activated state. Such an injection actuator is typically a simple key or button that is in mechanical or electrical contact with a dispensing mechanism located within the pen injection system, and pressing the button causes the injection mechanism to fire and inject the medication contained within the pen injection system. In some pen injector systems, the dose setting wheel is configured to rotate not only during dose setting, but also during injection.

[0005] For example, the PCT application published as WO2021 / 260404 discloses an injection monitoring module adapted and configured to be detachably mounted to the proximal end of an injection pen system for delivering a drug, the injection pen system having a pen body, a proximally located dose setting wheel connected to the body, and an injection actuator, the dose setting wheel being rotatable about a central longitudinal axis of the pen injection system during dose setting and being fixed to prevent rotation during injection. In particular, the injection monitoring module comprises:

[0006] a hollow body adapted and configured to be coaxially mounted about a body of the pen injection system, the hollow body comprising a central longitudinal bore and a central longitudinal axis, the central longitudinal bore having a proximal end and a distal end;

[0007] a magnetic field generating device located on or within the hollow body at a proximal end of the central longitudinal bore;

[0008] an injection monitoring system, including at least one or more magnetic sensors, the injection monitoring system being located at a proximal end of the bore of the hollow body;

[0009] The hollow body further comprises an inner sleeve located within the central longitudinal bore, the inner sleeve being configured to frictionally engage with an outer surface of the dose setting wheel to rotate synchronously with the dose setting wheel about the central longitudinal axis during dose setting without axial translation along the central longitudinal axis; wherein

[0010] The inner cannula is connected to the injection monitoring system; and

[0011] The connection between the inner sleeve and the injection monitoring system is adapted and configured to synchronously rotate the inner sleeve and the injection monitoring system about the central longitudinal axis during dose setting, and to translate the injection monitoring system along the central longitudinal axis but not to rotate the injection monitoring system about the central longitudinal axis during injection and / or expulsion of the drug from the pen injection system.

[0012] As used herein, the terms "pen injection system" and "injection pen system" are used interchangeably to refer to generally hand-held pen-shaped injection systems, which are well known per se and commercially available for the treatment of many different medical indications. These systems are generally designed to be self-injected by a user who needs to be treated for a given medical indication, whereby the drug can be selected from a variety of substances or combinations of substances having therapeutic or biological activity, so that it has become commonplace for patients suffering from or susceptible to such medical indications to carry these devices with them when needed.

[0013] The injection monitoring module is adapted and configured to be removably attached to an injection pen system equipped with a proximally located dose setting wheel and an injection actuator. The dose setting wheel rotates around the central longitudinal axis of the pen injection system to allow the user to set the dose of the drug for injection. The dose setting wheel is usually rotatable in clockwise and counterclockwise directions, which usually correspond to an increase in the selected dose to be administered and a decrease in the selected dose, respectively. The injection actuator is usually a button, usually located proximal to the dose setting wheel, and in most injection pens, at the proximal end of the injection pen system. After the dose has been set, and when the user of the injection system presses the injection actuator in the distal direction, a piston is usually mechanically or electromechanically driven, which is connected to a plunger, so that the drug is discharged from a chamber in the injection pen body through a needle, which is inserted by the user into an appropriate injection site, such as skin, fatty tissue or muscle, depending on the type of drug to be administered. The dose setting wheel is usually (but not necessarily) also coupled to the injection drive mechanism so that it also rotates as the drug injection proceeds. The functionality of such an injection system is well known in the art. However, the monitoring module described in WO2021 / 260404 is mounted on a pen-type injection system in which the dose setting wheel does not normally rotate during the injection / injection phase of operation.

[0014] The injection monitoring module is adapted and configured to be removably attached to the proximal end of such an injection pen system. The expressions "removably attachable", "removably attached", "removably mounted" or "removably mounted" as may be used in the present specification should be understood to refer to the possibility to attach or mount and subsequently remove the injection monitoring module, for example in case of transferring the injection monitoring module to another pen injection system, or for example if the monitoring module is damaged during use and needs to be replaced. Such attachment and subsequent removability may be achieved by providing a coupling device on the monitoring module, which couples in a releasable manner engages with the proximal end of the pen injection system, for example by friction or elastic engagement, or by other releasable fastening means, such as a clip, a band, a thread and a corresponding fastening ring, etc., which engage with the dose setting wheel or the injection actuator or both.

[0015] The hollow body of the injection monitoring module includes a central longitudinal bore having a proximal end and a distal end, the bore being sized to allow the hollow body to be coaxially mounted to and surround the body of the pen injection system.

[0016] The hollow body further comprises an inner sleeve located within the central longitudinal bore, the inner sleeve being configured to frictionally engage with an outer surface of the dose setting wheel to synchronously rotate about the central longitudinal axis without axially translating along the central longitudinal axis, but to rotate with the dose setting wheel during dose setting, such that if the inner sleeve rotates, the dose setting wheel also rotates in the same direction and to the same or the same rotation angle. In this way, it can be said that the inner sleeve rotates synchronously with the dose setting wheel.

[0017] The hollow body is suitably made of any suitable material, such as a durable polymer or plastic material, such as high density or high impact polypropylene. Advantageously, the hollow body is made of a transparent, translucent or opaque material so that the user can understand and identify any visual cues, such as light emitting diodes, which may also be provided or integrated into the injection monitoring module, wherein such cues may optionally be used to indicate various operating states of the injection monitoring system. Similarly, the inner sleeve is also suitably made of a suitable material, such as a durable polymer or high impact plastic material, such as ABS.

[0018] Furthermore, the inner sleeve is connected or coupled to an injection monitoring system. The connection or coupling between the inner sleeve and the injection monitoring system is adapted and configured to synchronously rotate the inner sleeve and the injection monitoring system around the central longitudinal axis during dose setting, and to translate the injection monitoring system along the central longitudinal axis during injection and / or expulsion of the drug from the pen injection system, but not to rotate the injection monitoring system around the central longitudinal axis. To this end, the connection between the inner sleeve and the injection monitoring system is configured to selectively rotate around the central longitudinal axis and then selectively translate along the longitudinal axis, the two movements being mutually exclusive.

[0019] The hollow body further comprises a distal body portion which extends around and frictionally engages with the outer surface of the body of the injection pen system at a position remote from the dose setting wheel. In this way, the hollow body is held in position on and around the body of the pen injection system distal to the dose setting wheel, so that the dose setting wheel is free to rotate within the bore of the hollow body. Such a friction-elastic configuration may be provided, for example, by a suitable elastomeric coating or deposit on the inner circumferential surface of the hollow body, for example in one or more regions, or as a continuous, contiguous or semi-continuous / contiguous coating deposited on the inner circumferential surface of the hollow body. The purpose of such a friction-elastic coating or deposit is to provide a friction clamp between the distal body portion and the injection pen body so as to maintain the correct positioning of the hollow distal body portion relative to the injection pen body. Suitable types of elastomeric materials capable of providing a corresponding friction engagement are known per se in the art.

[0020] The injection monitoring module also includes an injection monitoring system including at least one or more magnetic sensors, the injection monitoring system being located at a proximal end of the bore of the hollow body.

[0021] Although the device described in WO2021 / 260404 is useful, the applicant has found that some pen-type injection systems on the market are provided with a pen body that is shaped in such a way near the proximal end of the injection pen that the user has difficulty in properly installing the injection monitoring module as described in WO2021 / 260404 on the proximal end of the pen body, or removing it from the proximal end of the pen body, or adjusting its installation position, especially in young, frail or otherwise physically impaired users. For example, such as Connect TM and The injection pen systems of the present invention are provided with a pen body having a portion at a proximal end of the pen body with an increased outer diameter compared to the rest of the injection pen body and compared to the corresponding outer diameters of the dose setting wheel and the activation button, the increased diameter gradually tapering to a smaller outer diameter towards a distal end of the pen body. Summary of the invention

[0022] The Applicant proposes to address the disadvantages of known infusion monitoring modules, such as those described in the preceding paragraphs, through the present invention.

[0023] Therefore, one aspect of the present invention is an injection monitoring module adapted and configured to be detachably mounted to a proximal end of an injection pen system for delivering a drug, the injection pen system having a pen body, a dose setting wheel located proximal to the body and connected to the body, and an injection actuator, the dose setting wheel being rotatable about a central longitudinal axis of the pen injection system during dose setting, wherein the injection monitoring module comprises:

[0024] a hollow body adapted and configured to be coaxially mounted about a body of the pen injection system, the hollow body comprising a central longitudinal bore and a central longitudinal axis, the central longitudinal bore having a proximal end and a distal end;

[0025] a magnetic field generating device located on or within the hollow body at a proximal end of the central longitudinal bore;

[0026] an injection monitoring system, including at least one or more magnetic sensors, the injection monitoring system being located at a proximal end of the bore of the hollow body;

[0027] The hollow body further includes an inner sleeve positioned within the central longitudinal bore, wherein the inner sleeve is configured to frictionally engage an outer surface of the dose setting wheel to synchronously rotate with the dose setting wheel about the central longitudinal axis during dose setting without axial translation along the central longitudinal axis;

[0028] wherein the inner sleeve is connected to the injection monitoring system, and the connection between the inner sleeve and the injection monitoring system is adapted and configured to synchronously rotate the inner sleeve and the injection monitoring system about the central longitudinal axis during dose setting, and to translate the injection monitoring system along the central longitudinal axis during injection and / or expulsion of drug from the pen injection system;

[0029] The hollow body further comprises a distal body portion extending around the outer surface of the body of the injection pen system at a position away from the dose setting wheel, the distal body portion comprising a diameter changing device configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion from a first value to a second value different from the first value.

[0030] According to another aspect, the diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal bore of the distal body portion from a first value to a second value that is smaller than the first value.

[0031] According to another aspect, the diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal bore of the distal body portion from a first value to a second value greater than the first value.

[0032] According to another aspect, the diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion from a first diameter, in which the distal body portion does not frictionally contact the outer surface of the injection pen device when mounted on the injection pen device, to a second diameter smaller than the first diameter, in which the distal body portion frictionally contacts the outer surface of the injection pen device, the frictional contact preventing axial and radial movement of the distal body portion along and around the outer surface of the injection pen device.

[0033] As can be understood from the above, the diameter changing device comprises one or more components, the function of which when operated, actuated or activated is to dynamically change the inner diameter of the central longitudinal hole of the distal body portion. As mentioned in this specification, the inner diameter of the central longitudinal hole is considered to be a diameter defined or definable by the diameter formed by the radially innermost surface portion of the distal body portion. The dynamic change of the inner diameter of the central longitudinal hole of the distal body portion is configured to produce a controlled or controllable reduction in the inner diameter of the central longitudinal hole of the distal body portion, or a controlled or controllable increase, for example, based on the interaction between multiple components of the diameter changing device. For example, when the injection monitoring module is fixed to the outer surface of the injection pen system, more specifically, to the outer surface of the injection pen body, a controlled reduction in the diameter of the inner diameter of the central longitudinal hole of the distal body portion will be appropriate. Similarly, in the opposite sense, a controlled increase in the diameter of the inner diameter of the central longitudinal bore of the distal body portion would be appropriate when releasing or detaching the injection monitoring module from the outer surface of the injection pen system, more specifically, from the outer surface of the injection pen body, or when the injection monitoring module needs to be repositioned.

[0034] Therefore, according to one aspect, the diameter changing device includes a first rotatable outer component and a second non-rotatable inner component, wherein the diameter changing device is configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion by rotation of the first rotatable outer component around and against the second non-rotatable inner component.

[0035] The hollow body including the distal body portion is advantageously made of a suitable material, such as a molded plastic material, for example selected from ABS (acrylonitrile butadiene styrene polymer), PC (polycarbonate polymer), POM (polyoxymethylene monomer) and ABS-PC (acrylonitrile butadiene styrene polycarbonate copolymer), wherein ABS-PC is advantageously preferred. Optionally and advantageously, the hollow body including the distal body portion may be at least partially made of a transparent or translucent material, such as one of the above materials, to facilitate observation of the axial positioning of the injection monitoring module relative to the proximal end of the injection pen system when the injection monitoring module is mounted on the injection pen system.

[0036] According to another aspect, the first rotatable outer part is a rigid outer ring. The rigid outer ring may also be made of one or more of the above-mentioned plastic materials, but preferably and advantageously, is made of a transparent plastic material, such as polycarbonate polymer and / or acrylonitrile butadiene styrene polycarbonate copolymer.

[0037] According to another aspect, the second non-rotatable internal component is suitably configured as a deformable inner ring. For example, when formed as a ring, the non-rotatable internal component is provided with a proximal end and a distal end, and a wall extending from the proximal end to the distal end, the wall defining a hole having an inwardly facing surface defining an inner diameter and an outwardly facing surface defining an outer diameter. The non-rotatable internal component is physically connected to the hollow body at the distal end of the hollow body, for example by welding or bonding, for example by ultrasonic welding, or alternatively by friction surface engagement, for example by a press fit or snap engagement between a proximal-facing end face of the non-rotatable internal component and a distal-facing end face of the hollow body. In this way, when the injection monitoring module is mounted on the pen-type injection system, the non-rotatable component is not allowed to rotate around the body of the pen-type injection system. As described above, the second non-rotatable internal component is deformable. In general, and advantageously, the deformation of the second non-rotatable inner part is configured to operate by reducing the inner diameter of the second non-rotatable inner part due to the application of a radially inwardly directed pressure on the outwardly facing surface of the second non-rotatable inner part. This can be organized in a number of different ways, for example, the second non-rotatable deformable inner part, such as a ring as an example, can be provided with at least one or more cut-out or removed portions of wall material, whereby the cut-out or removed areas are distributed radially around the second non-rotatable deformable inner part, for example distributed at equal and regular intervals around the diameter of the second non-rotatable deformable inner part, and preferably also extend along an axis perpendicular to the inner diameter of the second non-rotatable inner part, for example extending at least a portion of the way along the wall from a first proximal end of the deformable inner part in a distal direction, or alternatively terminating at a position adjacent to the distal end of the non-rotatable inner part. The removal or cut-out portions of material allow the non-rotatable inner part to bend or elastically deform when radial pressure is applied in a radially inward direction on the outwardly facing wall surface of the non-rotatable inner part.

[0038] According to another aspect, the second non-rotatable inner component, e.g. formed as a deformable inner ring, comprises a radially inward surface portion of an elastomeric material. The elastomeric material may be distributed over all or part of the radially inward surface of the second non-rotatable inner component. The elastomeric material is selected to provide a frictional clamping of the radially inward surface of the second non-rotatable inner component when the second non-rotatable inner component is in frictionally engaged contact with an outer surface of the injection pen system, e.g. a pen body, thereby preventing the injection monitoring module from moving along the body of the injection pen system or being moved to an incorrect position along the pen body. Suitable elastomers for this task are thermoplastic elastomers, e.g. SEBS or polystyrene-poly(ethylene butylene)-polystyrene block copolymers, and are known per se in the art.

[0039] According to another aspect, the radially inward surface portion of the resilient material has a first thickness at a first point along a radius of curvature of the inward surface portion and a second thickness different from the first thickness at a second point along the radius of curvature of the inward surface portion. A thickness variation is provided along the radius of curvature of the inward surface portion such that the deformability provided to the second non-rotatable inner component is amplified when a relatively small force is applied to the surface of the outward surface of the second non-rotatable inner component. In this way, a relatively small force applied to the outward surface of the second non-rotatable inner component will have a diameter changing effect that is not only in accordance with the thickness variation of the resilient material along the radius of curvature but also in accordance with the diameter variation of the outward surface of the injection pen body, thereby ensuring a perfect fit of the resilient material to the injection pen body.

[0040] According to another aspect, the first rotatable outer part of the diameter changing device comprises at least one or more radially inward portions, and the one or more radially inward portions are configured to press against and deform the second non-rotatable inner part when the first rotatable outer part rotates around and against the second non-rotatable inner part. It should be understood here that the first rotatable outer part of the diameter changing device is thus configured to generate a force against the second deformable non-rotatable inner part by the presence of the at least one or more radially inward portions, and when the first rotatable outer part rotates, the force causes the second non-rotatable inner part to deform.

[0041] According to another aspect, the at least one or more radially inward portions of the first rotatable outer component are equally spaced from one another around an inner circumference of the first rotatable outer component, the first rotatable outer component being configured to press against the second non-rotatable inner component.

[0042] According to another aspect, the at least one or more radially inward portions of the first rotatable outer member comprises three equally spaced radially inward portions.

[0043] According to another aspect, the radially outward surface of the second non-rotatable inner component of the diameter changing device is configured to accommodate the at least one or more radially inward portions of the first rotatable outer component. It should be understood here that "configured to accommodate" means that the radially outward surface of the second deformable non-rotatable inner component of the diameter changing device is appropriately and suitably adapted, sized, formed, assembled and / or provided with physically defined features that enable the second inner component to accommodate the at least one or more radially inward portions of the first rotatable outer component, or the plurality of radially inward portions of the first rotatable outer component are physically engaged with the radially outward surface of the second deformable non-rotatable inner component, and the latter is appropriately deformed by the physical engagement to change the inner diameter of the second inner component.

[0044] According to another aspect, the radially outward surface of the second non-rotatable inner component of the diameter changing device includes an annular groove configured to receive and frictionally engage the at least one or more radially inward portions of the first rotatable outer component.

[0045] According to another aspect, when rotating, at least one or more radially inward portions of the first rotatable outer component engage and abut against an annular groove of the radially outward surface of the second non-rotatable inner component, and the at least one or more radially inward portions of the first rotatable outer component are moved from a first radial position to a second radial position around the rotation axis of the first rotatable outer component, the second radial position being different from the first radial position, thereby dynamically changing the inner diameter of the second non-rotatable inner component from the first inner diameter to the second inner diameter.

[0046] According to another aspect, the first rotatable outer part comprises an alignment mark, which is positioned or located on the outwardly facing surface of the first rotatable outer part and is configured to move from a first radial position which is not longitudinally aligned with the alignment mark on the outwardly facing surface of the hollow body to a second radial position which is longitudinally aligned with the alignment mark on the outwardly facing surface of the hollow body when the first rotatable outer part is rotated about the rotation axis. The alignment mark on the first rotatable outer part is used to provide visual feedback to the user and indicate when the first rotatable outer part is in the correct position for removing the injection monitoring module from the injection pen body, or to indicate that the injection monitoring module has been correctly positioned and fixed to the pen body, ready for monitoring dose setting and injection operations. The respective alignment mark may be suitably provided, for example, as a suitably shaped protrusion or additional material portion of material on the outwardly facing surface of the respective rotatable outer part and the hollow body, or alternatively as one or more colored areas on the outwardly facing surface, or as a suitable combination of a raised surface and a colored area. For example, when the alignment mark of the first rotatable outer component is longitudinally aligned along the length of the injection monitoring module, i.e., longitudinally aligned with the alignment mark located on the outwardly facing surface of the hollow body, the user knows that the injection monitoring has been properly positioned and secured, ready for use of the pen-type injection system and the injection monitoring module. When the alignment mark of the first rotatable outer component is not longitudinally aligned with the alignment mark located on the outwardly facing surface of the hollow body, the user knows that the injection monitoring module is not yet ready for use, and optionally, may be in a position to be removed or disassembled from the pen-type injection system.

[0047] According to another aspect, alternatively or in addition to providing alignment marks or colored areas, an indication of the correctly reached position for securing the injection monitoring module to the body of the injection pen or being removable or detachable therefrom may be suitably provided to the user by alternative or supplementary position feedback means different from the corresponding alignment marks or colored areas. Thus, the first outer rotatable part and the second inner non-rotatable part may be suitably shaped, configured and dimensioned to provide an alternative or supplementary position feedback, e.g. expressed as a rotational resistance, to the user when the rotation of the first outer rotatable part about the central longitudinal axis reaches the allowed predetermined limit. Each rotational limit of the first rotatable outer part relative to the second inner non-rotatable part and the corresponding rotational resistance corresponds to a position in which the injection monitoring module can be freely removed or detached from the injection pen body or, conversely, corresponds to a position in which the injection monitoring module is securely secured to the injection pen body and cannot perform any axial movement along the injection pen body or any radial or rotational movement around the injection pen body. Alternatively and / or additionally, the alternative or supplemental position feedback means may provide an audible signal, such as a click generated by the physical interaction of the first outer rotatable component against the second inner non-rotatable component, such as a groove provided on one of the respective components of the distal portion and a block on the other respective component, whereby the block is configured to engage and remain in the groove at or substantially adjacent to the point of maximum rotational resistance by elastic deformation. Such an audible signal thus indicates to the user that the respective rotational stop position has been reached. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The present invention will now be described in more detail with reference to examples accompanying the following drawings, in which:

[0049] Figure 1 is a schematic perspective view of an injection monitoring module mounted on an injection pen system ready for use;

[0050] Figure 2 When installed in Figure 1 Schematic cross-sectional view of an injection monitoring module when mounted on an injection pen system.

[0051] Figure 3 yes Figure 1 A schematic exploded perspective view of an injection monitoring module;

[0052] Figure 4 yes Figure 1 and Figure 2 A schematic perspective view of a portion of an injection monitoring module;

[0053] Figure 5 yes Figure 1 and Figure 2 a schematic end view of a portion of a distal portion of an injection monitoring module;

[0054] Figure 6 yes Figure 1 and Figure 2 A schematic perspective view of another portion of the distal portion of the injection monitoring module;

[0055] Fig. 7A yes Figure 1 and Figure 2 a schematic cross-sectional end view of the relative radial positions of components of a distal portion of an injection monitoring module of FIG. 1 , the injection monitoring module being in a first position;

[0056] Figure 7B is based on Fig. 7A A schematic perspective view of an outward surface of a distal portion of an injection monitoring module;

[0057] Fig. 8A yes Figure 1 and Figure 2 a schematic cross-sectional end view of the relative radial positions of components of a distal portion of an injection monitoring module of FIG. 1 , the injection monitoring module being in a second position;

[0058] Figure 8B is based on Fig. 8A Schematic stereoscopic view of the outward surface of the distal portion of the injection monitoring module. DETAILED DESCRIPTION

[0059] Now go to Figure 1 , Figure 2 and Figure 3, showing a schematic stereogram, a cross-sectional diagram and an exploded stereogram of an injection monitoring module (1) according to the present invention. The injection monitoring module (1) is mounted on a handheld injection pen system (2), the handheld injection pen system comprising a pen injection system body (3), the pen injection system body (3) having an outer peripheral surface (4), a pen cover (5) covering the distal end of the pen injection system, a dose setting or dialing wheel (6) located at the proximal end of the pen injection system body (3), and a dialed dose visualization window (7) located distal to the dose setting wheel (6), the dialed dose visualization window showing the dose that has been dialed by the user of the pen injection system. The injection monitoring module (1) according to the present invention is located and adjacent to the proximal end (8) of the injection pen system (2), in particular at least partially surrounding and contacting the outer peripheral surface (4), surrounding and contacting the pen body (3), and extending in the proximal direction beyond the proximal end (8) of the pen body (3), in particular beyond the dose setting wheel (6). Also shown is a central longitudinal axis (9) which passes through the longitudinal axial center of the injection monitoring module (1) and the injection pen system body (3). The injection pen system (2) is provided with an activator button (10) which is located proximal to the dose setting or dialing wheel (6), as can be found in several commercially available injection pen systems. Figure 1 and Figure 2 In the pen injection system shown, the dose setting wheel rotates about the central longitudinal axis (9) during dose setting, but is fixed and does not rotate during injection. Many injection pens that function in this way are currently commercialized, such as FlexTouch Connect TM , and Both are available from Novo Nordisk A / S.

[0060] The injection monitoring module (1) comprises a hollow body (11) sized and dimensioned to be coaxially mounted around a body (3) of a pen injection system (2). The hollow body (11) comprises a central longitudinal bore (12) having a proximal end (13) and a distal end (14) and a central longitudinal axis coinciding with the central longitudinal axis (9).

[0061] The hollow body further comprises a distal body portion (15) which, when mounted in a ready-to-use position, surrounds and frictionally engages with an outer surface (4) of a body (3) of an injection pen system (2) at a position on the pen body (3) remote from a dose setting wheel (6). The frictional engagement of the hollow body (11) with the outer surface (4) of the pen body (3) can be achieved by providing an elastic friction material (16) on an inner peripheral surface (17) of the hollow body. The hollow body (11) extends in a proximal direction above and beyond the limit of an actuator button (10) of the pen injection system (2), so that the hole (12) accommodates the dose setting wheel (6) and the actuator button (10), and the dose setting wheel is freely rotatable in the hole (12). The proximal end (13) of the hole corresponds to the proximal end of the hollow body (11).

[0062] The hollow body (11) further comprises a magnetic field generating means (18, 19) located on or within the hollow body (11), located at the proximal end (13) of the central longitudinal hole (12). The magnetic field generating means (18, 19) is suitably provided by a pair of single dipole magnets (18, 19) diametrically opposed to each other, each magnet having a north (N) pole and a south (S) pole, each pair of poles being preferably axially aligned along the central longitudinal axis from NS, with the north pole being located proximally and the south pole being located distally. The dipole magnets (18, 19) may be suitably formed in the shape of a rod, or alternatively in the shape of a disk or ring, or any other suitable shape. The magnets are located in corresponding recesses (20, 21) of suitable size provided in the hollow body (11), the recesses (20, 21) being located at the proximal end (13) of the body (11). Alternatively, the magnetic field generating means may be a single dipole annular magnet located on the peripheral proximal surface of the hollow body (11) at the proximal end (13) of the hollow body or in a corresponding annular groove. As can be understood from the above, the magnetic field generating means does not rotate freely around the central longitudinal axis because when the injection monitoring module is ready for use, the hollow body (11) is mounted on the pen body (3) around the central longitudinal axis (9) in a fixed positional relationship relative to the pen body (3).

[0063] The hollow body (11) further comprises an inner sleeve (22) located within the central longitudinal bore (12), the inner sleeve being configured to frictionally engage with an outer surface of the dose setting wheel (6) to rotate synchronously about the central longitudinal axis (9) without axially translating along the central longitudinal axis, but to rotate synchronously with the dose setting wheel (6) during dose setting.

[0064] Injection monitoring module Figure 3 In this view, the hollow body (11), the distal portion (15) and the corresponding proximal end (13) and distal end (14) are shown. Figure 3It is also shown that the hollow body (11) is shaped to have an inner diameter that gradually widens from the proximal end toward a point (23) adjacent or proximal to the distal end (14) of the distal portion (15). The widening diameter corresponds to the widening of the hole (12), so that the hollow body can be inserted over and around the proximal end of the pen and mounted on the dose setting wheel (6) of the pen, while leaving enough space in the hole to accommodate the inner sleeve (22) so that the latter can engage with the outer surface of the dose setting wheel. Accordingly, the inner sleeve (22) is provided with a suitable contact or engagement surface (24) on an inwardly facing side of the inner sleeve (22), and a corresponding contact or engagement surface (25) is provided on the injection monitoring system housing (26), which extends from the injection monitoring system housing in a distal direction into the aperture (12), the engagement surface (24) and the engagement surface (25) cooperating to form engagement surfaces for frictionally contacting and engaging with an outer surface of the dose setting wheel (6) and the activation button (10), respectively.

[0065] The distal portion (15) is Figure 3 It is mainly shown as a two-part system separated from the hollow body (11), but from Figure 2As can be seen in the figure, when the distal part (15) and the hollow body (11) are mounted on the body (3) of the pen-type injection system (2), the distal part (15) is preassembled with the hollow body (11). During factory assembly of the injection monitoring module, the distal part (15) and the hollow body (11) can be appropriately matched together, for example, by spot welding the proximal facing surface of one of the components of the distal part and the distal facing surface of the hollow body. Alternatively and / or additionally, the hollow body (11) can be provided with a radially outwardly extending distal annular skirt (27) and a distal annular wall (28) at its distal end (14), which extends from the hollow body (11) and terminates in the radially outwardly extending distal annular skirt (27). The distal annular wall (28) has a smaller outer diameter than the outer diameter of the skirt (27). The distal body portion (15) is designed and configured to extend around the outer surface (4) of the injection pen body (3) at a position remote from the dose setting wheel. The distal body portion (15) comprises a diameter changing device configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion from a first value to a second value different from the first value. Thus, the diameter changing device provides a controlled and dynamic reduction or increase of the inner diameter of the hole (12) in the distal body portion (15). In operation, the diameter changing means of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal bore of the distal body portion (15) from a first diameter in which the outwardly facing surface (17) of the distal body portion is not in frictional engagement contact with the outer surface (4) of the injection pen body (3) when mounted on the injection pen device to a second diameter smaller than the first diameter in which the outwardly facing surface (17) of the distal body portion is in frictional engagement contact with the outer surface (4) of the injection pen body (3), the frictional engagement contact preventing axial movement of the distal body portion (15) along the outer surface (4) of the injection pen body (3). As already mentioned elsewhere in this specification, the inner diameter of the central longitudinal bore is considered to be a diameter defined or definable by a diameter formed by a radially innermost surface portion of the distal body portion (15).

[0066] More details on the characteristics of the hollow body (11) are given in Figure 4 , wherein the distal annular wall (28) and the distal annular skirt (27) have been identified and discussed. Figure 4As can be seen in the figure, the hollow body (11) is provided with a plurality of recesses (29a, 29b, 29c, 29d, 29e, 29f) which are located in the distal annular skirt (27) and extend from the distal end (14) through the distal annular wall (28) to the distal end (30) of the annular skirt (27). The recesses (29a-29f) are oriented along and parallel to the central longitudinal axis (9) and are advantageously equally spaced around the circumference formed by the distal annular skirt (27). As will be described below with reference to Figure 6 As described, the recesses (29a-29f) are shaped, sized and configured to accommodate and engage a correspondingly shaped, sized and configured proximal element of a portion of the distal portion (15). As described below, the distal annular skirt is also provided with a proximally facing surface (31), which is sized, shaped and configured to provide a contact surface for a portion of the distal portion (15). The hollow body (11) also includes an alignment mark (33) located on the radially outward surface (32) of the hollow body (11), which extends radially outward from the radially outward surface (32) and along and parallel to the central longitudinal axis (9). As required, the length and height of the alignment mark can be adapted to the target user and / or manufacturing constraints. When the hollow body (11) is mounted on the pen body (3), the alignment mark (33) serves as an indexing and positioning element of the hollow body relative to the dose visualization window (7) of the injection pen body (3), and the dose visualization window (7) is typically provided with dose markings (34, Figure 1 ).

[0067] In the embodiment shown in the figure, and Figure 3 , 5, 6, 7 and 8, the diameter changing means of the distal body portion (15) comprises a first rotatable outer member (15A) and a second non-rotatable inner member (15B), the inner diameter of the central longitudinal hole (12) in the distal body portion (15A / 15B) being dynamically changeable by the rotation of the first rotatable outer member (15A) around and against the second non-rotatable inner member (15B). The first rotatable outer member (15A) is typically shaped, dimensioned and configured as a rigid ring (35), the rigid ring (35) having an outward surface (36) and an outward surface (37). The outward surface (36) may be provided with optional gripping means, such as at least one or more or more ridges (38) extending radially outwardly from the outward surface (36) and aligned parallel to the longitudinal axis (9) to allow a user to grip the rigid outer ring with a hand or fingers and rotate it around the longitudinal axis (9). At the proximal end (39) of the rigid outer ring (35), the ring (35) is provided with a radially inwardly projecting shoulder (40) having a distally facing surface (41). When the distal portion (15) is assembled with the hollow body (11), the distally facing surface (41) of the projecting shoulder (40) is located on the proximal facing surface (31) of the distal annular skirt (27) and is slidably engaged with the surface in a face-to-face engagement, so that the rigid outer ring (35) can rotate about the longitudinal axis (9) while being supported by the proximal facing surface (31) of the distal annular skirt (27). The rigid outer ring (35) is also provided with at least one (see Figure 1 ) or Figure 5 As shown, a plurality of radially inwardly and radially inwardly extending portions (42a, 42b, 42c) are provided, each portion (42a, 42b, 42c) defining a respective inwardly facing surface (43a, 43b, 43c) facing the hole (12). Figure 5As shown, there are three radially inward portions (42a, 42b, 42c) and corresponding inward surfaces (43a, 43b, 43c), but less than three or more than three may be provided as required. Each radially inward and radially inwardly extending portion (42a, 42b, 42c) and corresponding inward surface (43a, 43b, 43c) is formed, dimensioned and configured to press against and deform the second non-rotatable inner member (15B) when the rigid outer ring (35) rotates around and against the second non-rotatable inner member (15B). It should therefore be understood that the inwardly facing and radially inwardly extending facing portions (42a, 42b, 42c) and corresponding inward surfaces (43a, 43b, 43c) generate a force to abut against the second deformable non-rotatable inner member (15B), and when the rigid outer ring (35) rotates, the force causes the second non-rotatable inner member (15B) to deform. Advantageously, each inwardly and radially inwardly extending portion (42a, 42b, 42c) is equally spaced around the circumference of the inwardly facing surface (37) of the rigid outer ring. Figure 5 It can also be seen that each inwardly and radially inwardly extending portion (42a, 42b, 42c) has a distally facing surface (44a, 44b, 44c) in which a seat groove (45a, 45b, 45c) is formed or arranged, for example, the seat groove (45a, 45b, 45c) is defined by a pair of parallel extending material ridges (46, 47), and the material ridges (46, 47) extend from the distally facing surface (44a, 44b, 44c) in the distal direction. The rigid outer ring (35) is also provided with an alignment mark (48) on the outward surface (36) of the ring (35), which is used to show the alignment or misalignment of the rigid outer ring (35) with the alignment mark (33) of the hollow body (11), and the misalignment between the two marks (33, 48) parallel to the longitudinal axis (9) of the injection monitoring module indicates that the injection monitoring module (1) is not firmly mounted on the pen body (3) and there is a possibility of removing the injection monitoring module (1) from the injection pen (2), while the alignment of the two marks (33, 48) parallel to the longitudinal axis (9) of the injection monitoring module (1) indicates that the injection monitoring module (1) is firmly mounted on the injection pen body (3) and is ready for monitoring injection.

[0068] like Figure 6As shown, the second non-rotatable inner component (15B) is configured as a deformable inner ring (49). The deformable inner ring (49) has a proximal end (50) and a distal end (52), wherein the proximal end (50) has a proximally facing surface (51), and the distal end (52) has a wall (53) extending from the proximal end (50) to the distal end (52), wherein the wall (53) defines a hole (54), and the hole (54) has an inward surface (55) and an outward surface (56), wherein the inward surface (55) defines an inner diameter, and the outward surface (56) defines an outer diameter. The deformable inner ring (49) is physically connected to the hollow body (11) at the distal end (14) of the hollow body (11) via a series of one or more noses (57a, 57b, 57c, 57d, 57e, 57f) extending in the proximal direction and protruding beyond the proximal end (50) and the proximal facing surface (51). The noses (57a-57f) are respectively engaged with the recesses (29a-29f) by elastic frictional engagement and / or welded (e.g., by ultrasonic welding) or adhered to the recesses (29a-29f). The proximal end (50) and the nose (57a-57f) may also be shaped to have a truncated conical surface (58) that gradually widens in the distal direction from the proximal end (50) to facilitate insertion into, reception by, and engagement with the recesses (29a-29f). In this way, when the injection monitoring module (1) is mounted on the pen body (3), the non-rotatable deformable inner ring is prevented from rotating around the injection pen body (3). As described above, the inner ring (49) is deformable. The deformation of the inner ring (49) is achieved by providing at least one of the wall (53) materials or as Figure 6 The plurality of cut-away or removed portions (59a, 59b, 59c) shown are assisted by the cut-away or removed areas (59a, 59b, 59c) being radially distributed around the deformable inner ring (49), for example distributed at equal and regular intervals around the circumference of the inner ring (49). The cut-away portions (59a, 59b, 59c) preferably also extend along an axis perpendicular to the inner diameter of the inner ring (49), for example extending at least a portion in the distal direction along the wall (53) from the proximal end (50) of the deformable inner member, or alternatively terminating at a position adjacent to the distal end (52) of the non-rotatable inner ring (49). The removal or cut-away portions (59a, 59b, 59c) of the wall (53) material allow the non-rotatable inner ring to flex or elastically deform when radial pressure is applied in a radially inward direction against the outwardly facing wall surface (56) of the non-rotatable inner ring, and allow the non-rotatable inner ring to flex radially outward again to a default position when such radial pressure is removed or reduced.

[0069] As described above, the deformable inner ring (49) comprises a radially inward surface (55) provided with a portion of an elastomeric material and at least partially covering the inward surface (55). The elastomeric material may be distributed over all or part of the radially inward surface (55) of the second non-rotatable inner ring (49). The elastomeric material is selected to provide a friction grip to the radially inward surface (55) when the non-rotatable inner ring (49) is in frictional engagement contact with the outer surface (4) of the injection pen body (3), thereby preventing the injection monitoring module (1) from moving along the body (3) or being moved into an incorrect position. Suitable elastomers for this task are thermoplastic elastomers, such as SEBS or polystyrene-poly(ethylene butylene)-polystyrene block copolymers, and are known per se in the art.

[0070] The resilient material has a first thickness (t1) at a first point (r1) along the radius of curvature of the inwardly facing surface (55), and a second thickness (t2) different from the first thickness (t1) at a second point (r2) along the radius of curvature of the inwardly facing surface (55). The thickness variation is provided along the radius of curvature of the inwardly facing surface (55) so that the deformability provided to the non-rotatable inner ring (49) is amplified when a relatively small force is applied to the outwardly facing surface (56) of the wall (53) of the non-rotatable inner ring. In this way, a relatively small force applied to the outwardly facing surface (56) of the wall (53) of the non-rotatable inner ring will have a diameter changing effect that varies not only according to the thickness of the resilient material along the radius of curvature, but also according to the diameter of the outwardly facing surface (4) of the injection pen body (3), thereby ensuring that the resilient material is tightly attached to the injection pen body (3).

[0071] The deformable and non-rotatable inner ring (49) is also provided with at least one seat block (61a, 61b, 61c), for example located near the distal end (52) on the outward surface (56) of the wall (53) of the inner ring (49). The seat block is shaped, dimensioned and configured to fit in a groove (45a, 45b, 45c) provided on the distally facing surface (44a, 44b, 44c) of the inwardly facing and radially inwardly extending portion (42a, 42b, 42c) and is used to temporarily hold the inwardly facing and radially inwardly extending portion (42a, 42b, 42c) at a given radial position about the central longitudinal axis (9) when no rotational force is applied to the rigid outer ring (35).

[0072] The inner deformable and non-rotatable ring (49) is also provided with rotation stops (62a, 62b, 62c). The rotation stops extend from near the proximal end (50) in the direction of the distal end (52), such as extending distally to the frustoconical surface (58) of the proximal end. The rotation stops (62a, 62b, 62c) also extend radially outwardly, thereby defining a raised transverse bar extending on the outward surface (56). Each rotation stop (62a, 62b, 62c) together with adjacent rotation stops (62a, 62b, 62c) defines an arc of permitted movement of the inwardly and radially inwardly extending portion (42a, 42b, 42c) of the outer ring (35) about the axis (9). The stops are positioned around the circumference of the outwardly facing surface (56) of the wall (53) of the inner ring so that the corresponding positions of the inwardly facing and radially inwardly extending portions (42a, 42b, 42c) of the outer ring (35) exert a minimum or maximum radial force on the outwardly facing surface (56) of the deformable inner ring so that the ring is in a minimum radial compression state or a maximum radial compression state, respectively. In other words, the rotation stops (62a, 62b, 62c) and the corresponding proximal and distal ends (50, 52) of the inner deformable and non-rotatable ring (49) define an annular groove that is divided into a series of arcuate portions that allow rotational movement of the inwardly facing and radially inwardly extending portions (42a, 42b, 42c) of the outer ring (35).

[0073] Now we will refer to Fig. 7A , Figure 7B , Fig. 8A and Figure 8B Describe the function of the distal segment. Fig. 7A An end cross-sectional view of the injection monitoring module (1) around the pen body (3) in a first, unsecured position is shown, and the relative radial positions of the various elements of the rotatable rigid outer ring (35) and the non-rotatable deformable inner ring are shown. Figure 7B A perspective view of an injection monitoring module (1) mounted on an injection pen body (3) but not fixed is shown. The lack of alignment between the alignment mark (33) of the hollow body (11) and the alignment mark (48) located on the outer surface (36) of the outer ring (35) indicates that the mounting is not fixed. In these relative positions, the alignment mark (33) of the hollow body (11) and the alignment mark (48) located on the outer surface (36) of the outer ring (35) are not aligned. Fig. 7A It can be seen that the inward and radially inwardly extending portions (42a, 42b, 42c) of the outer ring (35) do not radially engage, depress or press against the inner ring (49), or if they do engage, have minimal inward radial force. For example, it can be seen that the inward and radially inwardly extending portion (42c) is in rotational abutment with the rotation stop (62c), but in this position it does not exert any radially inward force on the outwardly facing surface (56) of the inner ring (49), nor on the reduced thickness portion t1 at radial point r1. Fig. 7A The arrow on the left indicates the direction of the rotational force or action applied by the user on the outer ring (35) when the user wishes to fix the distal part (15) and the injection module (1) as a whole to the injection pen body (3). In the figure, the rotation is counterclockwise, but the distal part can be configured to act in the opposite direction, that is, by applying a clockwise rotational force or action on the outer ring (35). When the user rotates the outer ring in the counterclockwise direction, the inwardly and radially inwardly extending portions (42a, 42b, 42c) rotate in the counterclockwise direction. In doing so, they follow the arc of the groove defined between the rotation stop (62a, 62b, 62c) and the outward surface (56) of the wall (53), and press against and abut against the outward surface (56) of the wall (53), moving to contact and press against the portion t2 of increased thickness at the radial point r2. Due to the multiple cut-out or removed portions (59a, 59b, 59c) of the wall (53), the wall (53) is deformed simultaneously under radial inward pressure, thereby reducing the inner diameter. The reduction in the inner diameter of the hole causes the resilient portion located on the inwardly facing surface (55) of the inner ring to form an elastic and frictionally engaged contact with the outwardly facing surface (4) of the pen body, thereby fixing the distal portion to the pen body (3).

[0074] Fig. 8A and Figure 8B The fastened or fixed installation of the injection module (1) is shown with its distal portion in a correctly aligned position on the pen body (3), and the relative radial positions of the elements of the distal portion (15) are shown. Fig. 8A In the figure, it can be seen that the inwardly facing and radially inwardly extending portions (42a, 42b, 42c) of the outer ring (35) are pressed down on the outer surface (56) of the inner ring (49) at a position (r2) about the axis (9) at which the thickness of the elastomer is at a maximum (t2). In addition, the inwardly and radially inwardly extending portions (42a, 42b, 42c) of the outer ring are in rotational abutment with the rotational stops (62a, 62b, 62c) and additionally seat simultaneously on the seats (61a, 61b, 61c) of the inner ring by means of these seats engaging in grooves (45a, 45b, 45c) provided on the inwardly and radially inwardly extending portions (42a, 42b, 42c) of the outer ring. Figure 8BIn these relative positions, the user is informed that the injection monitoring module is securely mounted on the pen body due to the visible alignment between the alignment mark (33) of the hollow body (11) and the alignment mark of the outer ring (35) of the distal portion (15). In addition, when the outer ring is rotated to the rotation stop position, the movement of the inwardly and radially inwardly extending portions (42a, 42b, 42c) and grooves (45a, 45b, 45c) of the outer ring against the seats (61a, 61b, 61c) of the inner ring provides physical or tactile feedback to the user. The user feels this physical or tactile feedback when the ridges (46, 47) defining the grooves (45a, 45b, 45c) are pushed against the seats (61a, 61b, 61c), wherein the ridges (46, 47) elastically deform to allow the seats to elastically engage in the grooves (45a, 45b, 45c), thereby generating an audible signal, such as a click. The clicking sound is therefore a form of feedback which indicates to the user that the distal portion of the injection monitoring module is securely fixed to the injection pen body, or that the distal portion of the injection monitoring module can be removed from the injection pen body when the block (61a, 61b, 61c) engages in the groove (45a, 45b, 45c) in the opposite rotational stop position. Thus, in order to remove the injection monitoring module (1) from the pen body (3), the outer ring is rotated in the opposite direction, i.e. in the example shown, in a clockwise direction, to release or eliminate the inward radial force of the outer ring pressing down on the inner ring, allowing the inner ring to return to its default nominal size.

Claims

1. An injection monitoring module adapted and configured to be removably mounted to a proximal end of an injection pen system for delivering a drug, the injection pen system having a pen body, a proximally located dose setting wheel connected to the body, and an injection actuator, the dose setting wheel being rotatable about a central longitudinal axis of the injection pen system during dose setting and being fixed against rotation during injection, wherein the injection monitoring module comprises: a hollow body adapted and configured to be coaxially mounted about the body of the injection pen system, the hollow body comprising a central longitudinal bore and a central longitudinal axis, the central longitudinal bore having a proximal end and a distal end; a magnetic field generating device located on or within said hollow body at said proximal end of said central longitudinal bore; an injection monitoring system, including at least one or more magnetic sensors, the injection monitoring system being located at a proximal end of the bore of the hollow body; The hollow body further comprises an inner sleeve located within the central longitudinal bore, the inner sleeve being configured to frictionally engage an outer surface of the dose setting wheel to rotate synchronously with the dose setting wheel about the central longitudinal axis during dose setting without axial translation along the central longitudinal axis; wherein the inner sleeve is connected to the injection monitoring system, and the connection between the inner sleeve and the injection monitoring system is adapted and configured to synchronously rotate the inner sleeve and the injection monitoring system about the central longitudinal axis during dose setting, and to translate the injection monitoring system along the central longitudinal axis but not to rotate the injection monitoring system about the central longitudinal axis during injection and / or expulsion of drug from the injection pen system; Wherein, the hollow body further comprises a distal body portion extending around the outer surface of the body of the injection pen system at a position away from the dose setting wheel, the distal body portion comprising a diameter changing device configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion from a first value to a second value different from the first value.

2. The injection monitoring module according to claim 1, wherein: The diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal bore of the distal body portion from a first value to a second value that is smaller than the first value.

3. The injection monitoring module according to claim 1, wherein: The diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal bore of the distal body portion from a first value to a second value greater than the first value.

4. The injection monitoring module according to claim 1, wherein: The diameter changing device of the distal body portion is configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion from a first diameter, in which the distal body portion does not frictionally contact the outer surface of the injection pen device when mounted on the injection pen device, to a second diameter smaller than the first diameter, in which the distal body portion frictionally contacts the outer surface of the injection pen device, the frictional contact preventing the distal body portion from axially moving along the outer surface of the injection pen device.

5. The injection monitoring module according to claim 1, wherein: The diameter changing device of the distal body portion includes a first rotatable outer component and a second non-rotatable inner component, wherein the diameter changing device is configured to dynamically change the inner diameter of the central longitudinal hole of the distal body portion by rotation of the first rotatable outer component around and against the second non-rotatable inner component.

6. The injection monitoring module according to claim 1, wherein: The first rotatable outer member is a rigid outer ring.

7. The injection monitoring module according to claim 1, wherein: The second non-rotatable inner component is a deformable inner ring.

8. The injection monitoring module according to claim 7, wherein: The deformable inner ring includes a radially inwardly facing surface portion of an elastomeric material.

9. The injection monitoring module according to claim 8, wherein: The radially inward surface portion of the resilient material has a first thickness at a first point along a radius of curvature of the inward surface portion and has a second thickness different from the first thickness at a second point along the radius of curvature of the inward surface portion.

10. The injection monitoring module according to claim 5, wherein: The first rotatable outer component includes at least one or more radially inward portions, and the one or more radially inward portions are configured to press against a radially outward surface of the second non-rotatable inner component and deform the inner component when the first rotatable outer component rotates around and against the second non-rotatable inner component.

11. The injection monitoring module according to claim 10, wherein: The at least one or more radially inward portions of the first rotatable outer component are equally spaced from one another around an inner circumference of the first rotatable outer component and are configured to press against the radially outward surface of the second non-rotatable inner component.

12. The injection monitoring module according to claim 10 or 11, wherein: The at least one or more radially inward portions of the first rotatable outer member comprises three radially inward portions equidistantly spaced from one another.

13. The injection monitoring module according to claim 10, wherein: The radially outward surface of the second non-rotatable inner component of the diameter changing device is configured to receive the at least one or more radially inward portions of the first rotatable outer component.

14. The injection monitoring module according to claim 10, wherein: The radially outward surface of the second non-rotatable inner component of the diameter changing device includes an annular groove configured to receive and frictionally engage with the at least one or more radially inward portions of the first rotatable outer component.

15. The injection monitoring module according to claim 14, wherein: When rotating, the at least one or more radially inward portions of the first rotatable outer component engage and abut against the annular groove of the radially outward surface of the second non-rotatable inner component, and cause the at least one or more radially inward portions of the first rotatable outer component to move around the rotation axis of the first rotatable outer component from a first radial position to a second radial position different from the first radial position, thereby dynamically changing the inner diameter of the second non-rotatable inner component from the first inner diameter to the second inner diameter.

16. The injection monitoring module according to claim 5, wherein: The first rotatable outer component includes an alignment mark located on an outward surface of the first rotatable outer component, the alignment mark being configured to move from a first radial position that is not longitudinally aligned with the alignment mark located on the outward surface of the hollow body to a second radial position that is longitudinally aligned with the alignment mark located on the outward surface of the hollow body when the first rotatable outer component rotates about a rotation axis.

17. The injection monitoring module according to claim 5, wherein: The distal portion includes a position feedback device configured to provide position feedback regarding rotation of the first rotatable outer member relative to the second non-rotatable inner member about the central longitudinal axis.

18. The injection monitoring module according to claim 17, wherein: The position feedback device is configured to generate a region of increased resistance to rotation or stopped rotation of the first rotatable outer component relative to the second non-rotatable inner component.

19. The injection monitoring module according to claim 17, wherein: The position feedback device is configured to generate an audible signal, such as a click, to indicate that a rotational stop position of the first rotatable outer part relative to the second non-rotatable inner part has been reached.

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