Dose detection and drug identification for drug delivery devices

Abstract

A dose detection system for use in conjunction with a drug delivery device is provided. [Solution] The system includes a module including a sensor keyed to the device and operable to detect the relative angular position of a sensed element attached to the drug delivery device. The system determines the type of drug contained in the device and / or the type of device based on the detected angular position of the sensed element. In another aspect, the dose detection system is used in combination with a drug delivery device including a dose setting member that rotates relative to an actuator during dose delivery. The dose detection system includes a sensor and is operable to detect the relative angular position of the sensed element attached to the dose setting member during dose delivery to determine the delivered dose. Related methods are also disclosed.

Description

[Technical field]

[0001] The present disclosure relates to an electronic dose detection system for a drug delivery device, and in particular to an electronic dose detection module adapted for removably mounting to a proximal end portion of the drug delivery device. Alternatively, the dose detection module may be integrated with the drug delivery device. The dose delivery detection system is operable to detect the dose of drug delivered by the drug delivery device and / or the type of drug included in the drug delivery device. [Background technology]

[0002] Patients suffering from various ailments frequently must inject themselves with medication. To allow humans to conveniently and accurately self-administer medication, various devices, popularly known as pen-type injectors or injection pens, have been developed. Generally, these pens are loaded with a cartridge that includes a piston and contains multiple doses of liquid medication. A drive member is movable forward to advance the piston in the cartridge to dispense the contained medication from an outlet at the distal cartridge end, typically through a needle. In disposable or pre-filled pens, after the pen has been utilized to exhaust the supply of medication in the cartridge, the user discards the entire pen and begins using a new, alternative pen. In reusable pens, after the pen has been utilized to exhaust the supply of medication in the cartridge, the pen is disassembled to allow the used cartridge to be replaced with a new cartridge, and the pen is then reassembled for subsequent use.

[0003] Many pen injectors and other drug delivery devices utilize mechanical systems in which members rotate and / or translate relative to one another in a manner proportional to the dose delivered by operation of the device. Thus, the art has endeavored to provide a reliable system for accurately measuring the relative motion of members of a drug delivery device to assess the delivered dose. Such a system may include a sensor secured to a first member of the drug delivery device that detects the relative motion of a sensed component secured to a second member of the device.

[0004] Administration of an appropriate amount of drug requires that the dose delivered by the drug delivery device be accurate. Many pen injectors and other drug delivery devices do not include functionality for automatically detecting and recording the amount of drug delivered by the device during an injection event. In the absence of an automated system, patients must manually track the amount and time of each injection. Thus, a device operable to automatically detect the dose delivered by the drug delivery device during an injection event is needed. Furthermore, such a dose detection device needs to be removable and reusable with multiple delivery devices. In other embodiments, such a dose detection device needs to be integrated with the delivery device.

[0005] Delivering the correct medication is also important. A patient may need to select either a different medication, or a different form of a given medication, depending on the situation. Making a mistake about which medication is in the medication delivery device will result in the medication not being administered properly to the patient and inaccurate recording of the administration of the dose. The likelihood of this occurring is greatly reduced when a dose detection device is used that automatically verifies the type of medication contained in the medication delivery device. Summary of the Invention

[0006] The present disclosure relates to a drug delivery device having a dose detection system and associated control system configured to determine an amount of drug delivered from the drug delivery device based on detection of relative rotation within the drug delivery device. The relative rotation may occur between a dose setting member and an actuator and / or a housing of the drug delivery device. The dose delivery detection system comprises an electronics assembly attached to the actuator and a sensed component attached to or including the dose setting member. The electronics assembly includes a rotation sensor operable with the sensed component to detect rotation of the dose setting member relative to the actuator during dose delivery. The electronics assembly may further include various additional components such as one or more other sensors, memory, a processor, a controller, a battery, etc. The dose delivery detection system and associated electronics assembly may be fully integrated with the pen.

[0007] In another aspect, the dose delivery detection system includes a module that is removably attachable to the drug delivery device. Among other advantages, the attachable and removable dose delivery detection module operates to detect the amount of drug delivered without altering the functionality or operation of the drug delivery device to which it is attached. In some embodiments, it provides redundant sensors to add robustness to the dose detection system. In some embodiments, the detection system records the size of the delivered dose and communicates that information to an external device. Those skilled in the art will recognize other advantages.

[0008] In a further aspect, a dose type detection system is provided that is operable to detect a type of drug delivery device and / or a type of drug contained in the drug delivery device. The dose type detection system comprises a module removably mountable to an actuator member. The module includes a sensor component capable of detecting a sensed component attached to the drug delivery device. The module is keyed for attachment to the drug delivery device at a predefined angular position. The sensor is operable to detect an angular position of the sensed component relative to the sensor to determine a type of drug contained in the drug delivery device.

[0009] In another embodiment, the module includes both a drug delivery system and a drug type detection system to detect both the amount of drug delivered and the type of drug contained in the drug delivery device. Also included is a method for determining the dose delivered and / or the type of drug contained in the drug delivery device. [Brief description of the drawings]

[0010] The features and advantages of the present disclosure will become more apparent to those skilled in the art from the following detailed description considered in conjunction with the accompanying drawings.

[0011] [Figure 1] FIG. 1 is a perspective view of an exemplary drug delivery device in which the dose detection system of the present disclosure is operable. [Diagram 2] 2 is a cross-sectional perspective view of the exemplary drug delivery device of FIG. 1. [Diagram 3] FIG. 2 is a perspective view of a proximal portion of the exemplary drug delivery device of FIG. 1. [Figure 4] FIG. 2 is a partially exploded perspective view of a proximal portion of the exemplary drug delivery device of FIG. 1 together with a dose delivery detection system of the present disclosure. [Diagram 5] FIG. 13 is a side partial cross-sectional schematic view of a dose detection system module according to another exemplary embodiment mounted on a proximal portion of a drug delivery device. [Figure 6]FIG. 13 is a cross-sectional view of a module of a dose delivery detection system according to an exemplary embodiment mounted on a proximal portion of a drug delivery device. [Figure 7] A top view schematic diagram showing a rotational sensor arranged to detect a magnetic sensed element attached to a dose setting member according to an exemplary embodiment. [Figure 8] FIG. 8 is a perspective view of the dose setting member of FIG. 7 including a magnetic detectable element. [Figure 9] FIG. 13 is a perspective view of an alternative embodiment of a magnetic dose delivery detection system. [Figure 10A] 13 illustrates yet another exemplary embodiment of a dose delivery detection system utilizing magnetic sensing. [Figure 10B] 13 illustrates yet another exemplary embodiment of a dose delivery detection system utilizing magnetic sensing. [Figure 11A] 13 illustrates yet another exemplary embodiment of a dose delivery detection system utilizing magnetic sensing. [Figure 11B] 13 illustrates yet another exemplary embodiment of a dose delivery detection system utilizing magnetic sensing. [Figure 12A] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 12B] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 12C] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 12D] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13A] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13B] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13C] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13D] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13E]1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13F] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 13G] 1 illustrates an exemplary embodiment of a dose detection system utilizing inductive sensing. [Figure 14] 1 illustrates an exemplary embodiment of a keying system useful in a dose-type delivery system. [Figure 15] 1 illustrates an exemplary embodiment of a keying system useful in a dose-type delivery system. [Figure 16] 1 illustrates an exemplary embodiment of a keying system useful in a dose-type delivery system. [Figure 17] 1 illustrates an exemplary embodiment of a keying system useful in a dose-type delivery system. [Figure 18] 13 is a cross-sectional view of a module of a dose detection system according to another embodiment shown attached to a proximal portion of a drug delivery device. FIG. [Figure 19] FIG. 1 is a schematic diagram showing an arrangement of sensors and sensed components useful in an exemplary embodiment of a dose detection system. [Figure 20] FIG. 20 is a schematic diagram showing the dose detection system of FIG. 19. [Figure 21] 20 is a graph showing the output response of the dose detection system of FIG. 19. [Figure 22] FIG. 13 is a cross-sectional view of a dose detection system according to another embodiment, in which the sensor and the sensed element are integrated into a drug delivery device. [Figure 23A] 1A-1C are schematic diagrams illustrating exemplary embodiments of a dose detection system utilizing optical sensing of the rotation and / or position of a skirt relative to a sensor component. [Figure 23B] 1A-1C are schematic diagrams illustrating exemplary embodiments of a dose detection system utilizing optical sensing of the rotation and / or position of a skirt relative to a sensor component. [Figure 23C] 1A-1C are schematic diagrams illustrating exemplary embodiments of a dose detection system utilizing optical sensing of the rotation and / or position of a skirt relative to a sensor component. [Figure 24A] 13A-13C are schematic diagrams illustrating another exemplary embodiment of a dose detection system utilizing optical sensing of the rotation and / or position of a flange relative to a sensor component. [Figure 24B] 13A-13C are schematic diagrams illustrating another exemplary embodiment of a dose detection system utilizing optical sensing of the rotation and / or position of a flange relative to a sensor component. [Figure 25A] FIG. 1 illustrates an exemplary embodiment of a dose detection system utilizing capacitive sensing. [Figure 25B] FIG. 1 illustrates an exemplary embodiment of a dose detection system utilizing capacitive sensing. [Figure 25C] FIG. 1 illustrates an exemplary embodiment of a dose detection system utilizing capacitive sensing. [Figure 26] 1 is a cross-sectional view of a further exemplary drug delivery device of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same, it being understood, however, that no limitation of the scope of the invention is intended.

[0013] The present disclosure relates to a sensing system for a drug delivery device. In one aspect, the sensing system is for determining a dose delivered by the drug delivery device based on sensing a relative rotational movement between a dose setting member and an actuator of the drug delivery device. The sensed relative angular position or movement correlates with the dose delivered. In a second aspect, the sensing system is for determining the type of drug contained in the drug delivery device. By way of example, the drug delivery device is described in the form of a pen-type injector. However, the drug delivery device may be any device used to set and deliver a dose of a drug, such as an infusion pump, a bolus injector or an automatic injection device. The drug may be any of the types that can be delivered by such a drug delivery device.

[0014] The devices described herein, such as device 10, can further include a drug, for example, in the reservoir or cartridge 20. In another embodiment, a system can include one or more devices, including device 10, and a drug. The term "drug" refers to one or more therapeutic agents, including, but not limited to, insulin, insulin analogs such as insulin lispro or insulin glargine, insulin derivatives, GLP-1 receptor agonists such as dalaglutide or liraglutide, glucagon, glucagon analogs, glucagon derivatives, gastric inhibitory polypeptide (GIP), GIP analogs, GIP derivatives, oxyntomodulin analogs, oxyntomodulin derivatives, therapeutic antibodies, and any therapeutic agent capable of being delivered by the device described above. Drugs as used in the device may be formulated with one or more excipients. The device is operated by the patient, a caregiver, or a medical professional in a manner generally as described above to deliver the drug to a human.

[0015] An exemplary drug delivery device 10 is shown in FIGS. 1-4 as a pen injector configured to inject a drug into a patient through a needle. The pen injector 10 includes a body 11 with an elongated pen housing 12 including a distal portion 14 and a proximal portion 16. The distal portion 14 is received within a pen cap 18. With reference to FIG. 2, the distal portion 14 includes a reservoir or cartridge 20 configured to hold a drug fluid to be dispensed through its distal outlet end during a dispensing operation. The outlet end of the distal portion 14 is equipped with a removable needle assembly 22 including an injection needle 24 surrounded by a removable cover 25. A piston 26 is disposed within the reservoir 20. An injection mechanism disposed within the proximal portion 16 is operable to advance the piston 26 towards the outlet of the reservoir 20 during a dose dispensing operation to force the contained drug through the needle end. The injection mechanism includes a drive member 28 , illustratively in the form of a screw axially movable relative to the housing 12 for advancing a piston 26 through the reservoir 20 .

[0016] The dose setting member 30 is coupled to the housing 12 for setting the dose to be dispensed by the device 10. In the illustrated embodiment, the dose setting member 30 is in the form of a threaded element operable to helically move (i.e. move axially and rotationally simultaneously) relative to the housing 12 during dose setting and dose dispensing. Figures 1 and 2 show the dose setting member 30 fully threaded into the housing 12 at its home or zero dose position. The dose setting member 30 is operable to thread proximally out of the housing 12 until it reaches a fully extended position corresponding to the maximum dose deliverable by the device 10 in a single injection.

[0017] 2-4, the dose setting member 30 includes a cylindrical dose dial member 32 having a helically threaded outer surface that engages a corresponding threaded inner surface of the housing 12 to allow the dose setting member 30 to helically move relative to the housing 12. The dose dial member 32 further includes a helically threaded inner surface that engages a threaded outer surface of a sleeve 34 (FIG. 2) of the device 10. The outer surface of the dial member 32 includes dose indicative markings, such as numbers, viewable through a dose window 36 to indicate the set dose to a user. The dose setting member 30 further includes a tubular flange 38 coupled to the open proximal end of the dial member 32 and axially and rotationally locked to the dial member 32 by a detent 40 received within an opening 41 of the dial member 32. The dose setting member 30 further includes a collar or skirt 42 disposed around the outer periphery of the dial member 32 at its proximal end. The skirt 42 is axially and rotationally locked to the dial member 32 by tabs 44 which are received in slots 46 .

[0018] Thus, the dose setting member 30 may be considered to include any or all of the dose dial member 32, the flange 38, and the skirt 42, as they are all rotationally and axially fixed together. The dose dial member 32 is directly involved in setting the dose and driving the delivery of the medication. The flange 38 is attached to the dose dial member 32 and cooperates with a clutch to selectively couple the dial member 32 to the dose button 56, as described below. The skirt 42 provides a surface on the exterior of the body 11 to allow a user to rotate the dial member 32 to set a dose.

[0019] The skirt 42 illustratively includes a plurality of surface features 48 and annular ridges 49 formed on an outer surface of the skirt 42. The surface features 48 illustratively are longitudinally extending ribs and grooves spaced circumferentially around the outer surface of the skirt 42 to facilitate a user's gripping and rotating the skirt. In an alternative embodiment, the skirt 42 is removed or is integral with the dial member 32, and the user can grip and rotate the dose button 56 and / or the dose dial member 32 for dose setting. In the embodiment of FIG. 4, the user can grip and rotate the radially outer surface of the integral dose button 56, which also includes a plurality of surface features, for dose setting.

[0020] The delivery device 10 includes an actuator 50 having a clutch 52 received within the dial member 32. The clutch 52 includes an axially extending stem 54 at its proximal end. The actuator 50 further includes a dose button 56 disposed proximal to the skirt 42 of the dose setting member 30. In an alternative embodiment, the dose setting member 30 includes an integral dose button 56, shown in FIG. 26. The dose button 56 includes a mounting collar 58 (FIG. 2) centrally located on a distal face of the dose button 56. The collar 58 is attached to the stem 54 of the clutch 52, such as by an interference fit or ultrasonic welding, to axially and rotatably secure the dose button 56 and the clutch 52 together.

[0021] The dose button 56 includes a disk-shaped proximal end surface or face 60 and a distally extending annular wall portion 62 spaced radially inward of the outer periphery of the face 60, forming an annular lip 64 therebetween. The proximal face 60 of the dose button 56 serves as a pressing surface against which a force may be applied manually, i.e., directly by a user, to push the actuator 50 distally. The dose button 56 illustratively includes a centrally located concave portion 66 of the proximal face 60, although the proximal face 60 may alternatively be a flat surface. Similarly, the unitary dose button 56 shown in FIG. 26 may include a centrally located concave portion 66 of the proximal face 60, or alternatively may be a flat surface. A biasing member 68, illustratively a spring, is disposed between a distal surface 70 of the button 56 and a proximal surface 72 of the tubular flange 38 to bias the actuator 50 and the dose setting member 30 axially away from one another. The dose button 56 is depressible by a user to initiate a dose dispensing operation.

[0022] The delivery device 10 is operable in both a dose setting mode and a dose dispensing mode. In a dose setting mode of operation, the dose setting member 30 is dialed (rotated) relative to the housing 12 to set a desired dose to be delivered by the device 10. Dialing in the proximal direction functions to increase the set dose, and dialing in the distal direction functions to decrease the set dose. The dose setting member 30 is adjustable in rotational increments (e.g., clicks) that correspond to a minimum incremental increase or decrease in the set dose during a dose setting operation. For example, one increment or "click" may be equal to one-half or one unit of drug. The set dose is visible to the user via dial indicator markings shown through the dosing window 36. An actuator 50, including a dose button 56 and a clutch 52, moves axially and rotationally with the dose setting member 30 during dialing in the dose setting mode.

[0023] The dose dial member 32, flange 38, and skirt 42 are all rotationally fixed to one another and rotate to extend proximally of the drug delivery device 10 during dose setting due to the threaded connection between the dose dial member 32 and the housing 12. During this dose setting operation, the dose button 56 is rotationally fixed relative to the skirt 42 by complementary splines 74 (FIG. 2) of the flange 38 and clutch 52 which are biased together by a biasing member 68. During the course of dose setting, the skirt 42 and dose button 56 move helically from a "start" position to an "end" position relative to the housing 12. This rotation relative to the housing is proportional to the dose being set by operation of the drug delivery device 10.

[0024] Once the desired dose is set, the device 10 is manipulated so that the injection needle 24 is properly inserted, for example, into the user's skin. Operation in the dose dispensing mode is initiated in response to a distal axial force applied to the proximal face 60 of the dose button 56. The axial force is applied directly to the dose button 56 by the user, which causes the actuator 50 to move axially distally relative to the housing 12.

[0025] The axial movement of the actuator 50 compresses the biasing member 68, reducing or closing the gap between the dose button 56 and the tubular flange 38. This relative axial movement separates the clutch 52 and the complementary splines 74 on the flange 38, thereby releasing the actuator 50, e.g., the dose button 56, from its rotationally fixed relationship to the dose setting member 30. Specifically, the dose setting member 30 is rotationally decoupled from the actuator 50, allowing rearward drive rotation of the dose setting member 30 relative to the actuator 50 and the housing 12. The dose dispensing mode of operation may also be initiated by activating a separate switch or trigger mechanism.

[0026] As the actuator 50 continues to be pushed axially without rotation relative to the housing 12, the dial member 32 screws back into the housing 12 as it rotates relative to the dose button 56. Dose markings are visible through the window 36, indicating the amount still remaining to be injected. As the dose setting member 30 is screwed distally, the drive member 28 is advanced distally to force the piston 26 through the reservoir 20 and expel the medication through the needle 24 (FIG. 2).

[0027] During a dose dispensing operation, the amount of drug released from the drug delivery device is proportional to the amount of rotational movement of the dose setting member 30 relative to the actuator 50 as the dial member 32 is screwed back into the housing 12. Injection is completed when the female threads of the dial member 32 reach the distal end of the corresponding male threads of the sleeve 34 (FIG. 2). The device 10 is then again placed in the ready or zero dose position as shown in FIGS. 2 and 3.

[0028] The start and end angular positions of the dose dial member 32, and thus the rotationally fixed flange 38 and skirt 42, relative to the dose button 56 provide an "absolute" change in angular position during dose delivery. Determining whether the relative rotation has exceeded 360° may be determined in a number of ways. By way of example, a full rotation may be determined by also taking into account the incremental movement of the dose setting member 30, which may be measured in any number of ways by a sensing system.

[0029] Further details of the design and operation of the exemplary delivery device 10 can be found in U.S. Patent No. 7,291,132, entitled Medication Dispensing Apparatus with Triple Screw Threads for Mechanical Advantage, the entire disclosure of which is incorporated herein by reference. Another example of a delivery device is an automatic injection device that can be found in U.S. Patent No. 8,734,394, entitled "Automatic Injection Device With Delay Mechanism Including Dual Functioning Biasing Member," the entire disclosure of which is incorporated herein by reference, where such a device is modified with one or more of the various sensor systems described herein to determine the amount of drug delivered from the drug delivery device based on sensing relative rotation within the drug delivery device.

[0030] The dose detection system employs a sensing component and a sensed component attached to a member of a drug delivery device. The term "attached" encompasses any manner of fixing the position of a component to another component or member of a drug delivery device such that they are operable as described herein. For example, the sensing component may be attached to a member of a drug delivery device by being placed directly on the member, received within the member, integrated into the member, or otherwise connected to the member. The connection may include, for example, a connection formed by frictional engagement, spline, snap or press fit, sonic welding, or adhesive.

[0031] The term "directly attached" is used to describe an attachment where two components, or one component application and one member, are physically secured together without the use of an intermediate member other than the attachment component. The attachment component may comprise a fastener, adapter, or other part of the fastening system (such as a compression membrane) that is interposed between the two components to facilitate attachment. A "direct attachment" is distinguished from a connection where components / members are connected by one or more intermediate functional members, such as, for example, the way in which dial member 32 is connected to dose button 56 by clutch 52 in FIG. 2.

[0032] The term "fixed" is used to indicate that the indicated motion may or may not occur. For example, if two members are required to rotate and move together, then a first member is "rotationally fixed" with a second member. In one embodiment, a member may be "fixed" relative to another member functionally, rather than structurally. For example, one member may be pressed against another member such that a frictional engagement between the two members rotationally locks them together, but the two members cannot be fixed together without the pressing of the first member.

[0033] Various sensor systems are contemplated herein. In general, a sensor system includes a sensing component and a sensed component. The term "sensing component" refers to any component capable of detecting the relative position of the sensed component. The sensing component includes a sensing element or "sensor" along with associated electrical components for operating the sensing element. The "sensed component" is any component capable of detecting the position and / or movement of the sensed component relative to the sensing component. In the case of a dose delivery detection system, the sensed component rotates relative to the sensing component, thereby detecting the angular position and / or rotational movement of the sensed component. In the case of a dose type detection system, the sensing component detects the relative angular position of the sensed component. The sensing component can include one or more sensing elements, and the sensed component can include one or more sensed elements. The sensor system can detect the position or movement of the sensed component(s) and provide an output representative of the position(s) or movement(s) of the sensed component(s).

[0034] A sensor system typically detects a characteristic of a sensed parameter that varies in relation to the position of one or more sensed elements within a sensed region. The sensed elements extend into or otherwise influence the sensed region in a manner that directly or indirectly affects the characteristic of the sensed parameter. The relative positions of the sensor and the sensed elements affect the characteristic of the sensed parameter, allowing a controller of the sensor system to determine different positions of the sensed elements.

[0035] A suitable sensor system may include a combination of active and passive components. If the sensing component is operating as an active component, then both components do not need to be connected to other system elements such as a power source or a controller.

[0036] Any of a variety of sensing technologies capable of detecting the relative position of two members may be incorporated, such technologies may include, for example, technologies based on tactile, optical, inductive or electrical measurements.

[0037] Such techniques may include measuring a sensed parameter associated with a field, such as a magnetic field. In one form, a magnetic sensor detects changes in the sensed magnetic field when a magnetic component is moved relative to the sensor. In another embodiment, a sensor system may detect characteristics of and / or changes to the magnetic field when an object is placed in and / or moved through the magnetic field. The field variations change the characteristics of the sensed parameter associated with the position of the sensed element within the sensed region. In such an embodiment, the sensed parameter may be capacitance, conductance, resistance, impedance, voltage, inductance, etc. For example, a magnetoresistive sensor detects distortions in an applied magnetic field that result in a characteristic change in the resistance of an element of the sensor. As another example, a Hall effect sensor detects a change in voltage resulting from distortion of an applied magnetic field.

[0038] In one aspect, the sensor system detects the relative position or movement of the sensed element and therefore the associated member of the drug delivery device. The sensor system generates an output representative of the position(s) or amount of movement of the sensed component. For example, the sensor system may be operable to generate an output from which rotation of the dose setting member during dose delivery can be determined. A controller is operatively connected to each sensor to receive the outputs. In one aspect, the controller is configured to determine from the outputs a dose delivered by operation of the drug delivery device.

[0039] The dose delivery detection system includes detecting relative rotational movement between the two members. The sensor system operates to detect the amount of angular movement from the start of dose injection to the end of dose injection, with the degree of rotation having a known relationship to the dose delivered. For example, a typical relationship for a pen injector is that an angular displacement of 18° of the dose setting member is equal to one unit dose, although other angular relationships are also suitable. The sensor system is operable to determine the total angular displacement of the dose setting member during dose delivery. Thus, an angular displacement of 90° would result in five unit doses being delivered.

[0040] One approach to detecting angular displacement is to count dose increments as the injection progresses. For example, the sensor system can use a repeating pattern of sensed elements such that each repetition is indicative of a predefined degree of rotation angle. Conveniently, the pattern can be established such that each repetition corresponds to a minimum dose increment that can be set with the drug delivery device.

[0041] An alternative approach is to detect the start and stop positions of the relatively moving members and determine the delivered dose as the difference between those positions. In this approach, part of the determination may be for a sensor system to detect the number of full revolutions of the dose setting member. Various methods for this are well within the skill of the art and may include "counting" the number of increments to assess the number of full revolutions.

[0042] The sensor system components can be permanently or removably attached to the drug delivery device. In an exemplary embodiment, at least some of the components of the dose detection system are provided in the form of modules that are removably attached to the drug delivery device. This has the advantage that these sensor components can be used with more than one pen injector.

[0043] In some embodiments, the sensing component is attached to the actuator and the sensed component is attached to the dose setting member. The sensed component may also include the dose setting member or any part thereof. The sensor system detects the relative rotation of the sensed component, and thus the dose setting member, during dose delivery, and the dose delivered by the drug delivery device is then determined. In an exemplary embodiment, a rotation sensor is attached to the actuator and rotationally fixed. The actuator does not rotate relative to the body of the drug delivery device during dose delivery. In this embodiment, the sensed component is attached to the dose setting member, which rotates relative to the actuator and the device body during dose delivery, and rotationally fixed. The sensed component may also include the dose setting member or any part thereof. In an exemplary embodiment, the rotation sensor is not directly attached to the dose setting member, which rotates relative to the actuator and the device body during dose delivery.

[0044] 5, there is shown in schematic form a dose delivery detection system 80 including a module 82 useful in combination with a drug delivery device such as device 10. The module 82 carries a sensor system, shown generally at 84, including a rotation sensor 86 and other associated components such as a processor, memory, battery, etc. The module 82 is provided as a separate component that can be removably attached to the actuator.

[0045] The dose detection module 82 includes a body 88 that is attached to the dose button 56. The body 88 illustratively includes a cylindrical sidewall 90 and a top wall 92 that extends over and seals the sidewall 90. By way of example, in FIG. 5 the top wall 90 is shown generally as having inwardly extending tabs 94 that attach the module 82 to the dose button 56. The dose detection module 82 may alternatively be attached to the dose button 56 via any suitable fastening means, such as a snap or press fit, a threaded interface, etc., provided that in one embodiment the module 82 may be detached from a first drug delivery device and then attached to a second drug delivery device. Attachment may be anywhere on the dose button 56, provided that the dose button 56 may be moved axially any desired amount relative to the dose setting member 30, as discussed herein.

[0046] During dose delivery, the dose setting member 30 is free to rotate relative to the dose button 56 and the module 82. In an exemplary embodiment, the module 82 is rotationally fixed with the dose button 56 and does not rotate during dose delivery. This may be provided structurally, for example, with tabs 94 in FIG. 5, or by engaging opposing splines or other surface features on the module body 88 and the dose button 56 upon axial movement of the module 82 relative to the dose button 56. In another embodiment, pressing the module distally provides sufficient frictional engagement between the module 82 and the dose button 56 to keep them rotationally fixed together during dose delivery.

[0047] The top wall 92 is spaced from the face 60 of the dose button 56, thereby providing a cavity 96 that may contain some or all of the rotation sensor and other components. The cavity 96 may be open at the bottom or may be enclosed by a bottom wall 98 or the like. The bottom wall 98 may be positioned to directly abut the face 60 of the dose button 56. Alternatively, if the bottom wall 98 is present, it may be spaced from the dose button 56 and another contact between the module 82 and the dose button 56 may be used such that axial forces applied to the module 82 are transferred to the dose button 56. In another embodiment, the module 82 may be rotationally secured to the integral dose button 56 as shown in FIG. 26.

[0048] In an alternative embodiment, the module 82 during dose setting is instead attached to the dose setting member 30. For example, the side wall 90 may include a lower wall portion 100 having an inward projection 102 that engages the skirt 42 at a location below the ridge 49. In this approach, the tabs 94 may be omitted and the module 82 effectively engages the proximal face 60 of the dose button 56 and the distal side of the annular ridge 49. In this configuration, the lower wall portion 100 may be provided with surface features that engage with surface features of the skirt 42 to rotationally secure the module 82 to the skirt 42. Rotational forces applied to the housing 82 during dose setting are thereby transferred to the skirt 42 by the coupling of the lower wall portion 100 and the skirt 42.

[0049] To continue dose delivery, the module 82 is rotationally released from the skirt 42. The connection between the lower wall portion 100 and the skirt 42 is configured to disengage upon distal axial movement of the module 82 relative to the skirt 42, thereby allowing the skirt 42 to rotate relative to the module 82 during dose delivery.

[0050] Similarly, the module 82 may be coupled to both the dose button 56 and the skirt 42 during dose setting. This has the advantage of providing an additional coupling surface during rotation of the module in dose setting. The coupling of the module 82 to the skirt 42 is then released prior to dose injection, such as by axial movement of the module 82 relative to the skirt 42 when dose delivery is initiated, thereby allowing the dose setting member 30 to rotate relative to the module 82 during dose delivery.

[0051] In certain embodiments, a rotational sensor 86 is coupled to the sidewall 90 for detecting the sensed component. The bottom wall portion 100 also serves to reduce the possibility that a user's hand may inadvertently apply drag to the dose setting member 30 as it rotates relative to the module 82 and housing 12 during dose delivery. Furthermore, because the dose button 56 is rotationally fixed to the dose setting member 30 during dose setting, the sidewall 90, including the bottom wall portion 100, provides a single continuous surface that may be easily grasped and manipulated by the user during dose setting.

[0052] When the injection process is initiated by depressing the dose detection module 82, the dose button 56 and the dose setting member 30 are rotationally locked together. Moving the module 82, and therefore the dose button 56, a short distance, for example less than 2mm, releases the rotational engagement and allows the dose setting member 30 to rotate relative to the module 82 as the dose is delivered. Regardless of the use of a finger pad or other trigger mechanism, the dose detection system is activated before the dose button 56 has moved a sufficient distance to release the rotational lock between the dose button 56 and the dose setting member 30.

[0053] Illustratively, the dose delivery detection system includes an electronics assembly suitable for operation of the sensor system as described herein. A controller is operably connected to the sensor system to receive outputs from one or more rotation sensors. The controller may include conventional components such as a processor, power supply, memory, microcontroller, etc., contained within a cavity 96 defined by the modular body 88. Alternatively, at least some components may be provided separately, such as by a computer, smartphone, or other device. Means are then provided for operably connecting external controller components to the sensor system at appropriate times, such as by wired or wireless connection.

[0054] The exemplary electronics assembly 120 includes a flexible printed circuit board (FPCB) having multiple electronic components. The electronics assembly includes a sensor system including one or more rotation sensors 86 in operative communication with a processor to receive signals from the sensors representative of the sensed relative rotation. The electronics assembly further includes a microcontroller unit (MCU) with at least one processing core and internal memory. The system includes a battery, illustratively a coin cell battery, for powering the components. The MCU includes control logic operable to perform the operations described herein, including detecting a dose delivered by the drug delivery device 10 based on a detected rotation of the dose setting member relative to the actuator. In one embodiment, the detected rotation is between the skirt 42 and the dose button 56 of the pen injector.

[0055] The MCU is operable to store the detected dose in a local memory (e.g., an internal flash memory or an on-board EEPROM). The MCU is further operable to wirelessly transmit and / or receive a signal representative of the detected dose to a paired remote electronic device, such as a user's smartphone, via Bluetooth Low Energy (BLE) or other suitable short-range or long-range wireless communication protocol. Illustratively, the BLE control logic and the MCU are integrated on the same circuit.

[0056] Much of the sensing electronics is contained within the cavity 96. However, the rotational sensor may be located in a variety of locations to sense relative movement of the sensed component. For example, the rotational sensor may be located within the cavity 96, within the body 88 but outside of the cavity 96, or elsewhere in the body, such as in the bottom wall portion 100. The only requirement is that the rotational sensor be positioned to effectively detect rotational movement of the sensed component during dose delivery. In some embodiments, the rotational sensor is integrated with the device 10.

[0057] One or more sensed elements are attached to the dose setting member 30. In one aspect, the sensed element is attached directly to the skirt 42 of the dose setting member. Alternatively, the sensed element may be attached to any one or more of the dose setting components, including the dial member, the flange, and / or the skirt. The only requirement is that the sensing element(s) is / are positioned such that it is sensed by the rotation sensor during relative rotational movement during dose delivery. In other embodiments, the sensed component comprises the dose setting member 30 or any part thereof.

[0058] Further exemplary embodiments of the dose delivery detection system 80 are provided in Figures 6-13. The embodiments are shown somewhat diagrammatically since common details have already been provided with respect to Figures 1-5. Generally, each embodiment includes similar components of the dose detection module 82, including a body 88 having a cylindrical upper wall 90 and a top wall 92. Each embodiment also includes a lower wall 100, although it will be understood that variations of these components, including the absence of the lower wall 100, are within the scope of this disclosure. Other components in common with the previous description herein include the electronics assembly 120 contained within a cavity 96 of the module body 88, the dose button 56, the dose setting member 32 and the device housing 12. Additionally, in each embodiment, the dose detection module 82 is shown diagrammatically as being attached to the annular side wall 62 of the dose button 56, although alternative mounting configurations and mounting locations may be used. For example, the dose detection module 82 may be attached to the dose button 56, or in some embodiments, may be releasably attached to the skirt 42. The dose detection module 82 may also be attached to the integrated dose button 56 as shown in FIG.

[0059] Each example also illustrates the use of a particular type of sensor system. However, in some embodiments, the dose detection system includes multiple sensing systems using the same or different sensing technologies. This provides redundancy in case one of the sensing systems fails. It also provides the ability to use a second sensing system to periodically verify that the first sensing system is functioning properly.

[0060] In a particular embodiment, as shown in FIG. 6, a finger pad 110 is attached to the top wall 92 of the module 82. The finger pad 110 is coupled to the top wall 92, which is attached to the upper wall 90. The finger pad 110 includes a ridge 114 that extends radially inward and is received in a circumferential groove 116 in the wall component 92. The groove 116 allows for slight axial movement between the finger pad 110 and the wall component 92. A spring (not shown) typically biases the finger pad 110 upwardly and away from the wall component 92. The finger pad 110 may be rotationally fixed to the wall component 92. Axial movement of the finger pad 110 distally toward the module body 88 when an injection process is initiated may be used to trigger a selected event. One use of the finger pad 110 may be the activation of the drug delivery device electronics upon initial pressing and axial movement of the finger pad 110 against the module body 88 when a dose injection is initiated. For example, this initial axial movement may be used to "wake up" the device, particularly components related to the dose detection system. In one example, the module 82 includes a display for showing information to the user. Such a display may be integrated with the finger pad 110. The MCU includes a display driving software module and control logic operable to receive and process sensed data and display information on said display, such as, for example, dose setting, dispensed dose, status of injection, completion of injection, date and / or time, or time until next injection.

[0061] In the absence of a finger pad, the system electronics can be activated in a variety of other ways. For example, the initial axial movement of the module 82 at the start of dose delivery can be detected directly, such as by contact closure or physical engagement of a switch. It is also known to activate the drug delivery device based on a variety of other actions, such as removal of a pen cap, detecting pen movement using an accelerometer, or setting a dose. In many approaches, the dose detection system is activated prior to the start of dose delivery.

[0062] With reference to Figures 6-8, the dose detection module 82 operates with a magnetic sensing system 84. Two magnetic sensors 130 are located on the bottom wall portion 100 (illustratively on the inner surface of the bottom wall portion 100) on opposite sides of the skirt 42 of the dose setting member 30. For all embodiments, the number and location of the rotation sensor(s) and sensed element(s) may vary. For example, the embodiment of Figures 6-8 may instead include any number of magnetic sensors 130 spaced evenly or unevenly around the skirt 42. The sensed element 132 (Figures 7 and 8) includes a magnetic strip 134 fixed to the skirt 42, shown illustratively on the interior of the skirt 42. In the exemplary embodiment, the strip includes five pairs of north-south magnetic components, e.g., 136 and 138, such that each magnetic portion extends over 36°. The magnetic sensors 130 are spaced 18° apart (Figure 7) and read the digital position of the magnetic strip 132, and thus the skirt 42, in a two-bit Gray code format. For example, when the sensor detects the passage of the N-S magnetic pair, it detects that the skirt 42 has rotated 36°, which corresponds to 2 units of dosage, for example, added (or subtracted).

[0063] Other magnetic patterns including different numbers or positions of magnetic elements may also be used. Additionally, in an alternative embodiment, the sensed component 133 is attached to or integral with the flange 38 of the dose setting member 30, as shown in FIG.

[0064] As previously mentioned, the sensing system 84 is configured to detect the amount of rotation of the sensing element relative to the magnetic sensor 130. This amount of rotation directly correlates to the dose delivered by the device. The relative rotation is determined by detecting movement of the skirt 42 during dose delivery, for example, by identifying the difference between the start and stop positions of the skirt 42, or by "counting" the number of incremental movements of the skirt 42 during delivery of the drug.

[0065] 10-11, an exemplary magnetic sensor system 150 is shown that includes as a sensed element an annular ring-shaped bipolar magnet 152 having a north pole 154 and a south pole 156. The magnet 152 is attached to the flange 38 and therefore rotates with the flange during dose delivery. The magnet 152 may alternatively be attached to the dose dial 32 or other member that is rotationally fixed to the dose setting member.

[0066] The sensor system 150 further includes a sensor 158 including one or more sensing elements 160 operatively connected to sensor electronics (not shown) contained within the module 82. The sensing element 160 of the sensor 158 is shown in FIG. 11A mounted to a printed circuit board 162 which in turn is mounted to the module 82 which is rotationally fixed to the dose button 56. As a result, the magnet 152 rotates relative to the sensing element 160 during dose delivery. The sensing element 160 is operable to detect the relative angular position of the magnet 152. The magnetic sensor system 150 is thereby operative to detect the total rotation of the flange 38 relative to the dose button 56 and therefore relative to the housing 12 during dose delivery.

[0067] In one embodiment, the magnetic sensor system 150 includes four sensing elements 160 spaced equiradially within the module 82. Alternative numbers and locations of sensing elements may be used. For example, in another embodiment shown in FIG. 11B, a single sensing element 160 is used. Additionally, while the sensing element 160 in FIG. 11B is shown as being centered within the module 82, other locations may be used. In the above embodiment, the sensing element 160 is shown mounted within the module 82. Alternatively, the sensing element 160 may be mounted to any portion of the component that is rotationally fixed to the dose button 56 such that the component does not rotate relative to the housing 12 during dose delivery.

[0068] For purposes of illustration, the magnet 152 is shown as a single annular bipolar magnet attached to the flange 38. However, alternative configurations and locations of the magnet 152 are contemplated. For example, the magnet may include multiple poles, such as alternating north and south poles. In one embodiment, the magnet includes a number of pole pairs equal to the number of distinct rotational dose setting positions of the flange 38. The magnet 152 may also include several separate magnet members. In addition, the magnet components may be attached to any portion of a member that is rotationally secured to the flange 38 during dose delivery, such as the skirt 42 or the dose dial member 32.

[0069] The sensor system is alternatively illustrated in Figures 12-13 as an inductive sensor system 170. Sensor system 170 utilizes a sensed element 171 comprising a metal strip 172 attached to skirt 42 as the sensed element. Sensor system 170 further includes a sensor 174 comprising one or more sensing elements 176, such as four independent antennas 178 spaced equiradially around the circumference of skirt 42. These four antennas form two antenna pairs located 180 degrees apart to provide a ratiometric measurement of the angular position of skirt 42.

[0070] The metal band 172 is shaped such that one or more different rotational positions of the skirt 42 relative to the module 82 can be detected. The metal band 172 has a shape that generates a signal that changes as the skirt 42 rotates relative to the antenna 178. Illustratively, Figures 13A-13C show a band pattern, with Figure 13B showing a 90° rotation from the position of Figure 13A and Figure 13C showing a further 90° rotation. This pattern produces a sinusoidal response that is detected as the skirt 42 rotates relative to the module 82, as shown diagrammatically in Figure 12D, with positions a-d correlating with those shown in Figure 12A.

[0071] 13D provides a schematic diagram showing an inductive sensor system 170 integrated into the module 82 and skirt 42 of the pen 10. A metal band 172 is shown attached to the skirt 42. An antenna 178 is operatively connected to the electronics 120 such that the antenna functions to detect the position of the skirt 42 relative to the module 82, and thus relative to the housing 12 of the pen 10, during dose delivery.

[0072] In the embodiment shown in Figures 12-13, the inductive sensor system 170 includes four sensing elements 176 with antennas 178 spaced equiradially within the module 82. Alternative numbers and locations of sensing elements may be used. For example, another embodiment utilizes a single antenna. In the illustrated embodiment, the antenna 178 is shown mounted within the module 82. Alternatively, the antenna(s) may be mounted to any portion of the component that is rotationally fixed to the dose button 56 such that the component does not rotate relative to the housing 12 during dose delivery.

[0073] For purposes of illustration, the metal band 172 is shown as a single cylindrical band attached to the outside of the skirt 42. However, alternative configurations and locations of the metal band 172 are contemplated. For example, the metal band may include multiple individual metal elements. In one embodiment, the metal band includes a number of elements equal to the number of individual rotational dose setting positions of the skirt 42. The metal band in alternative examples may be attached to any portion of a component that is rotationally fixed to the skirt 42 during dose delivery, such as the flange 38 or the dial member 32. The metal band may include a metal element attached to a rotating member on the inside or outside of the member, or may be incorporated into such a member by metal particles incorporated into the component or by overmolding the component with the metal band.

[0074] The antenna 178 is shown diagrammatically in FIG. 12A and structurally as being circular in FIG. 13D and FIG. 13E. An alternative configuration of the antenna is shown diagrammatically in FIG. 13F and FIG. 13G. Shown in FIG. 13F is an "elongated antenna" 180 with a rectangular central portion 182 and semicircular ends 184. FIG. 13F shows the position of the antenna 180 relative to the metal strip 186. This position corresponds to a pen injector at rest with no axial displacement of the module as in the case of delivering a dose. In FIG. 13G, the antenna 180 is in a position corresponding to the module being pressed to cause delivery of a dose. The module, and therefore the antenna 180, is displaced downwards relative to the metal strip 186 in FIG. 13G. It is clear that the elongated antenna 180 may provide a more uniform detection of the metal strip 186 since there is a more constant area of ​​the central portion 182 overlapping with the metal strip.

[0075] In one aspect, a modular dose detection system is disclosed. The use of a removably attached module is particularly suited for use with a drug delivery device in which both the actuator and the dose setting member include portions that are external to the drug device housing. These external portions allow for direct attachment of a sensing component to the actuator, such as a dose button, and direct attachment of a sensed component to a dose setting member, such as a dose skirt, flange, or dial member, as described herein. In this regard, a "dose button" refers more generally to a component of a drug delivery device that includes a portion located outside the device housing and includes an exposed surface available for a user to use to deliver a set dose. Similarly, a dose "skirt" refers more generally to a component of a drug delivery device that is located outside the device housing and thus has an exposed portion available for a user to grip and rotate the component to set a dose. As disclosed herein, the dose skirt rotates relative to the dose button during dose delivery. Also, the dose skirt can be rotationally fixed to the dose button during dose setting, such that either the dose skirt or the dose button can be rotated to set a dose. In alternative embodiments, the delivery device may not include a dose skirt and the user may grasp and rotate the actuator (e.g. a dose button) to set the dose. In some embodiments, with the dose detection module attached to the actuator and / or dose skirt, the dose detection module can be rotated, thereby rotating the dose setting member of the delivery device to set the dose to be delivered.

[0076] A further feature of the present disclosure is that the sensing system of dose detection system 80 may be built into the drug delivery device from the start as an integrated system rather than as an add-on module.

[0077] The above provides a discussion of various structures and methods for sensing the relative rotation of the dose setting member with respect to the actuator during dose delivery. In certain embodiments of a drug delivery device, the actuator moves in a spiral manner relative to the pen body during dose setting. For illustrative purposes, the present disclosure describes a dose detection system for such a spirally moving actuator. However, one skilled in the art will understand that the principles and physical operation of the disclosed dose detection system may be used in combination with an actuator that rotates but does not translate during dose delivery. It will also be understood that the dose detection system is operable with medical delivery devices of other configurations, provided that the device includes an actuator that rotates with respect to the dose setting member during dose injection.

[0078] The detection system may also be used with a module for identifying (specifying) characteristics of the drug administered by the pen injector. Pen injectors are used with a wide variety of drugs and even with different types of a given drug. For example, insulin is available in different forms depending on the intended purpose. Types of insulin include fast-acting, short-acting, intermediate-acting and long-acting. In another perspective, the type of drug refers to which drug is involved, e.g. insulin vs. non-insulin drugs, and / or the concentration of the drug. It is important not to confuse the types of drugs as the consequences may be serious.

[0079] Certain parameters can be correlated based on the type of drug. Using insulin as an example, there are known limitations on the appropriate amount of dosage based on factors such as what type of insulin is involved and how the type of insulin correlates with the timing of administration. In another aspect, it is necessary to know what type of drug has been administered in order to accurately monitor and evaluate a treatment regimen. In one aspect, a sensor system is provided that can identify the type of drug administered.

[0080] To determine the drug type, a module is provided that detects the unique identification of the type of drug contained in the drug delivery device. When the module is attached to the drug delivery device, such as a pen-type injector, the module detects the type of drug and stores it in memory. The module can then evaluate the drug setting or delivery taking into account the type of drug in the pen, as well as previous administration history and other information.

[0081] 14, the pen injector 10 includes a sensor system 200 comprising a sensed component 202 and a sensing component 204. The sensor system 200 is operable to distinguish different angular orientations of the sensed component 202 relative to the pen injector 10. The sensor system 200 may be of any type as previously described, whereby a particular angular position can be identified.

[0082] 14 shows the pen injector 10 including the housing 12, the dose dial member 32, the flange 38, the clutch 52, the dose button 56 and the module 82. The sensed component 202 includes one or more sensed elements 206 attached to the pen injector 10 in a uniquely identifiable manner. By way of example, the sensed element 206 is shown attached to the skirt 42 and always having the same orientation relative to the skirt 42. The skirt 42 is rotatable relative to the housing 12, but has a uniquely identifiable position relative to the housing 12 when in an "initial zero position" prior to any medication being dispensed from the pen injector. Similarly, the sensed element 206 can be attached to other rotatable members of the pen that have a uniquely identifiable position for an appropriate period of time, such as during attachment of the module 82 to the pen injector 10. In this regard, the sensed element 206 may alternatively be attached to the flange 38 or the dial member 32, for example.

[0083] The skirt 42 includes a slot 208 extending axially outside the cylindrical skirt wall 210 (FIG. 15). The angular position of the slot 208 relative to the angular position of the sensed element 206 is predefined to correspond to a selected type of medication. With reference to FIG. 15, the slot 208 is shown in the 9 o'clock position where the skirt 42 is in its initial zero dose position. This position of the slot 208 is assigned to represent a particular type of medication. Alternatively, the slot 208 is located at a different angular position of the initial zero dose position, such as the 3 o'clock position in FIG. 15. This position is then assigned to represent a second type of medication. Thus, detection of the position of the sensed element 206 relative to the slot 208 is useful for identifying the medication type contained in the pen injector 10.

[0084] The module 82 includes a lower wall 212 that includes an inner surface 214 (FIG. 16). A tab 216 extends radially inward of the inner surface 214 and is configured to be received within the slot 208. This is shown diagrammatically in FIG. 15. The tab 216 may be a simple protrusion on the inner surface or may be provided as an arm capable of bending radially outward. To mount the module 82 to the device 10, the tab 216 is aligned with the slot 208 and then the module is advanced toward the device. The tab 216 is configured to ensure proper alignment with the slot 208 by having a blunt leading end 218. This is provided such that the tab 216 needs to be received within the slot 208 rather than improperly climbing over another location on the skirt.

[0085] Figure 14 shows the module during installation with the tab 216 received within the slot 208. In Figure 17, the module 82 has been advanced to its installed position with the tab 216 moved out of the slot 208. In this position, the module 82 may be secured to the dose button 56, for example, by the protrusion 220, as previously described. Locating the tab 216 outside the slot 208 allows for relative rotation between the skirt 42 and the module 82 after installation.

[0086] Identification of the drug type results from a predefined orientation of the sensed element relative to the slot 208. In the embodiment of Figures 14-17, this means that the sensed element is selectively positioned on the skirt 42 to represent the drug type. That way, whenever the tab 216 is aligned with the slot 208, the sensor system is operable to identify the relative angular relationship of the sensed element(s) to the module and derive the drug type therefrom. This detection occurs whenever the tab and slot are aligned. This alignment is required when the module is mounted on the skirt, so it is convenient to detect the position at this point. This may be caused by triggering the sensor system in any suitable manner, such as a proximity sensor, a sliding contact, a spring-loaded switch, or manual activation at the beginning of installation of the module.

[0087] Once the module is installed and the drug type is identified, the pen injector is ready for use. If desired, the module 82 can be removed from the pen injector and available for use in another pen injector. During operation, dose delivery rotates the skirt 42 relative to the module 82 so that at the end of dose delivery the tab and slot are not aligned. This does not affect the operation of the pen injector as the tab is axially displaced from the slot 208 and therefore may be in any angular position relative to the skirt 42. However, to facilitate removal of the module 82, the tab 216 includes a tapered rear end 222. This allows the tab 216 to easily overcome the outer surface 210 of the skirt 42 regardless of the angular position of the skirt. Drug type identification has been described using a tab and slot alignment mechanism. However, other alignment structures or systems are contemplated.

[0088] This drug type detection is useful for a variety of sensor systems that are operable to detect a predefined angular position of the sensed element relative to the alignment feature. These sensor systems include those previously disclosed herein. It is a further aspect that this drug type determination is easily combined with a sensor system to detect the delivered dosage. The two systems may operate independently or in concert with one another.

[0089] In certain embodiments, the sensor system used to detect dose delivery is also used to identify drug type. For example, Figures 10-11 and associated text describe a magnetic sensor system including a sensing element 160 and a magnet 152 to determine the dose delivered. The magnet 152 has a unique configuration such that the sensor system can detect a particular angular position of the magnet 152 relative to the sensing element. Thus, this same sensor system can be used in combination with alignment features, as described with respect to Figures 14-17, to identify the drug type contained in the pen injector. The inductive sensor system of Figures 12-13 is another example of a sensor system useful for determining both drug type and dose delivery.

[0090] 18-21, an alternative drug and / or pen type detection system 230 is provided. In this embodiment, a sensor system 230 is provided in association with a module 232. The module 232 is removably attached to the pen injector 10 in the same keyed manner as described with respect to the module 82 in the embodiment of FIGS. 14-17. The sensor system 230 comprises a sensed component 234 and a sensor 236. The sensor system 230 is operable to identify different angular orientations of the sensed component 234 relative to the pen injector 10. The drug and / or pen type identification results from a predefined orientation of the sensed element(s), as previously described. The sensor system is operable to identify the relative angular relationship of the sensed element to the module and derive the drug and / or pen type therefrom.

[0091] The angular position of the sensed component 234 is detected based on a unique angular profile of the sensed component. The term "unique angular profile" refers to the fact that one or more sensed elements 238 that comprise the sensed component 234 are in any predefined angular position used by the system. Also for This is used to identify a configuration of the sensed component that allows the angular position of the sensed component to be uniquely identified. A sensed component having such a unique angular profile is shown in Figures 19-21. Figure 19 illustrates generally one embodiment of a sensed component 234 and its relationship to a sensor 236. The sensed component 234 includes a single sensed element 238 formed in a generally circular pattern.

[0092] The sensor 236 is shown in FIG. 20 as including opposing pairs of induction coil antennas 246 and 248 arranged at equal radii around the axis of rotation 242 of the actuator 244. The antennas represent A+ / A- and B+ / B- pairs. The sensed component 234 is configured to rotate about the axis of rotation 242 and is positioned as shown in FIG. 20. An AC current flows through the pairs of antennas 246 and 248, generating four separate and independent AC magnetic fields.

[0093] As the sensed element 234 passes the antenna pair, the magnetic field of each antenna induces circulating currents (eddy currents) in the surface of the metal in the sensed element 234. This eddy current generates its own magnetic field, which opposes the original magnetic field generated by the antenna. As the metal of the sensed element 234 moves closer to the antenna coil, it blocks a larger portion of the electromagnetic field produced by that coil and blocks a smaller portion of the electromagnetic field of the other antenna. This means that the eddy currents increase as more of the electromagnetic field flux lines are blocked and decrease as less flux lines are blocked from the other coil. This change in eddy currents in each antenna changes the effective inductance of each individual antenna. The system can measure these changes in the inductance of each antenna 246 and 248 over time and use that data from the opposing coils 246 and 248 to offset undesirable variations due to temperature or mechanical tolerances. The result is two continuously changing waveforms that are 90 degrees out of phase, as shown in FIG. 21.

[0094] The corresponding levels of the two output signals can then be correlated to various rotational positions of the sensed component 234 relative to the sensor 236 enabling orthogonal rotational sensing. The system provides response data A and data B from A and B antenna pairs 246 and 248, respectively. The sensor system 230 is shown in the "0 position" in FIG. 20. From the shape and signal output of the sensed component 234, it is apparent that each relative rotational position of the sensed component 234 has a unique response signature and therefore the sensed component has a unique angular profile about the axis of rotation 242 of the actuator 244.

[0095] The output signal is processed and decoded to generate a unique signature for the sensed element 234 at a given position. Such processing may include signal processing to repeatedly sample the output or to convert the analog signal shown in FIG. 21 into separate digital square waves, also 90 degrees out of phase. A lookup table can be used to compare the current position information with previous position information to decode the direction of movement. For example, if the last decoded values ​​for output signals A and B were 00, respectively, and the current value is 01, then the sensed element is said to have moved half a step in the clockwise direction. The number of degrees of a given "step" is determined by the sampling rate of the analog signal. Increasing the sampling rate increases the rotational resolution as smaller changes in angular position are detected. However, to detect the type of drug or device, it is sufficient if the sensed component produces a unique signal output for any angular position that correlates to the type of drug or device, or any other information being detected.

[0096] The sensor system 230 is configured to detect one or more angular positions of the sensed component 234 relative to the sensor 236. The controller 250 is operable to respond to the one or more detected angular positions thereby to determine information regarding the drug delivery device 10.

[0097] In this exemplary embodiment, the module 232 is attached to the actuator 244 in a keyed relationship to place the module 232, and therefore the sensor 236, in a predetermined angular position relative to the actuator 244. This keyed relationship may be provided in the same manner as in the embodiment of Figures 14-17, for example, by having a slot 208 in the skirt 42 receive a tab 216 (Figure 18) of the module 232.

[0098] The predefined angular positions of the module 232 correlate with the type of drug delivery device 10 and / or the type of drug included in the drug delivery device 10. For example, the 0° position shown in FIG. 20 may indicate that the pen injector is a pen with a particular dosing capability, and the 90° position may indicate that the dosing is fast acting insulin. The 180° position may indicate, for example, that the drug delivery device is a pen injector containing a quantity of fast acting insulin. The correlation may be stored in a memory carried by the module 232. The controller is configured to determine an angular position of the sensed component 234 relative to a sensor 236 included in the module 232 and derive correlation information regarding the drug delivery device.

[0099] In another exemplary embodiment, the sensor system 230 is operable to determine the amount of drug delivered by the drug delivery device. According to this embodiment, the drug delivery device includes a dose setting member that rotates relative to the body of the drug delivery device during dose delivery. The actuator is axially and rotatably fixed to the dose setting member in a first mode of operation during dose setting. The actuator is non-rotatable relative to the device body in a second mode of operation during dose delivery. The sensor system 230 detects the rotation of the sensed component relative to the module during dose delivery and the controller derives the amount of drug delivered.

[0100] In a further embodiment, the sensor system of the drug delivery device is operable to determine both information about the drug delivery device itself and information about the amount of drug delivered by the drug delivery device. In this embodiment, the module 232 is attached to the drug delivery device, and the sensor system 230 detects the angular position of the sensed component 234 relative to the module 232. This position is correlated with the type of drug delivery device, the type of drug contained in the drug delivery device, or any other desired information. The drug is then delivered using the drug delivery device. During delivery, the sensor system 230 detects the rotation of the sensed component 234 relative to the sensor 236 as an indication of the amount of drug delivered.

[0101] 18, further exemplary details of a drug delivery system 252 are provided. The system 252 in FIG. 18 comprises a drug delivery device 10 including a device body 11, a dose dial member 32, a flange 38, a skirt 42, a clutch 52 and a dose button 56. The module 232 may be attached to the dose button 56 by a protrusion 220 extending inwardly from the module 232. In an initial attachment, the module 232 is oriented relative to the skirt 42 by having the tab 216 received within the slot 208. In this orientation, the position of the sensed component 234 relative to the sensor 236 correlates with the type of drug and / or the type of drug delivery device, as previously described.

[0102] For dose delivery, the module 232 and dose button 56 are advanced distally relative to the skirt 42 to the position of Figure 21. In this position, the skirt 42, dose dial member 32 and flange 38 move together while rotating relative to the dose button 56 as a dose of medication is delivered.

[0103] The sensed component 234 as shown includes a single sensed element provided as a metal band 254. As described with respect to Figures 19-21, the metal band 254 has a unique angular profile surrounding the axis of rotation 242. By way of example, the sensed element 238 is shown attached to the dose dial member 32. The dose dial member 32 is rotatable relative to the device body 11, but has a unique identifiable position relative to the device body 11 when in an "initial zero position" before any drug is dispensed from the drug delivery device. Similarly, the sensed element 238 can be attached to other rotatable members of the drug delivery device that have a unique identifiable position for an appropriate period of time, such as during mounting of the module 232 to the drug delivery device 10. In this regard, the sensed component 234 may alternatively be attached to, for example, the flange 38 or skirt 42.

[0104] The exemplary sensor system 230 is also useful as an integrated system in a drug delivery device, rather than being provided as a removable module. Referring to FIG. 22, a drug delivery device 310 is shown that is substantially similar to the device 10 of FIGS. 1-4. The drug delivery device 310 includes a device body 11 and a dose setting member 30 that includes a dose dial member 32, a flange 38, and a skirt 42. These components are configured to function as previously described. The actuator 50 includes a clutch 52 and a dose button 56 attached thereto. During dose setting, the dose button 56 is rotationally fixed to the dose setting member 30. To deliver a dose, this rotational fixation is released and the dose setting member 30 rotates relative to the dose button 56 in proportion to the dose delivered.

[0105] The drug delivery device 310 differs from the device 10 of Figures 1-4 in that it includes a dose detection system 312 comprising a sensed component 314 and a sensor 316. The sensor 316 is integrated into the dose button 56. The dose button 56 includes a bottom wall 318, a peripheral wall 320, and a top wall 322, which together form a compartment 324. The sensor 316 includes one or more sensor elements 326 supported within the compartment 324. Similarly, the integrated dose button 56 shown in Figure 26 can include an integrated sensor 316 and a compartment 324.

[0106] An electronics assembly 328 is also received within compartment 324 and operatively connected to sensor element 326. Electronics assembly 328 further includes a controller 330. Controller 328 is coupled to sensor element 320 to receive the sensor output and thereby determine information regarding the drug delivery device and / or its contents.

[0107] A sensed component 314 is attached to the dose setting member 30. With respect to the embodiment of Figures 18-21, the sensed component 314 comprises a metal strip or other sensed element having a unique angular profile. Although the sensed component 314 is shown attached to the dose dial member 32, it may be attached to other components of the dose setting member 30. A sensor 316 is positioned and configured to detect the relative angular position of the sensed component 314.

[0108] This embodiment differs from Figures 18-21 in that components of the dose detection system 312 are integrated into the drug delivery device 310. The sensing operation otherwise proceeds as described above, with the dose detection system operating to detect the type of drug delivery device, the type of drug, and / or the dose delivered by the drug delivery device, etc. In yet another alternative, the sensed component 314 is integrated into the drug delivery device 310, but the sensor 316 is included in a removable module as described above.

[0109] 23A-23C, an alternative embodiment using optical sensing is shown. As previously described, the module 82 is attached to the drug delivery device 10, which includes the dose button 56 and the skirt 42. The sensed element includes one or more detectable marks 350 applied to the top surface 352 of the skirt 42. The marks may include, for example, spots of visible or invisible ink applied to the skirt 42. The sensor system includes a camera assembly 354 mounted within the compartment 96. The camera assembly 354 is positioned to track the detectable mark(s) through rotation of the skirt 42 relative to the module 82, and includes suitable optics therefor.

[0110] In a similar embodiment, also using optical sensing, shown in Figs. 24A-B, a module 82 is provided that is attached to the drug delivery device 10. The sensed component includes one or more detectable marks 360 affixed to a top surface 368 of the flange 38. A camera assembly 364 is positioned to track the detectable mark(s) 360 through the rotation of the flange 38 relative to the module 82 and includes suitable optics therefor. For example, the camera assembly 364 may include a lens 366 that is positioned in alignment with a window (not shown) in the dose button 56 and, optionally, a notch 370 formed in the tab 94 of the side wall 90. To facilitate monitoring of the rotation of the flange 38, the detectable marks 360 may be provided in various patterns. It should be understood that any of the embodiments of Figs. 23 and 24 may be alternatively or additionally used to detect the absolute relative position of a skirt or flange based on the inclusion of unique detectable marks around the perimeter of the skirt or flange.

[0111] The sensor system is alternatively illustrated in Figures 25A-25C as a capacitive sensor system 380. The sensor system 380 utilizes a sensed element 382 comprising a metal strip 384 attached to the skirt 42. The sensor system 380 further includes a sensor 386 comprising one or more sensing elements, e.g., antennas or armatures 388, mounted on the sidewall 90 opposite the metal strip 384. The metal strip covers, e.g., half the circumference of the skirt 42, and forms a capacitive coupling between each pair of armatures as it rotates on the Z-axis. The two armature pairs, 180° apart, form two sensors in quadrature, providing a ratiometric measurement of the skirt's angular position.

[0112] Metal band 384 is shaped to detect the rotational position of skirt 42 relative to module 82. Metal band 384 has a shape that produces a signal that changes as skirt 42 rotates relative to antenna 384. The shape of metal band 384 and the position of the armature produce a sinusoidal response as skirt 42 rotates. A shield 390 on the outside of module wall 90 is connected to equipment ground 392 to isolate the sensor during operation.

[0113] For illustrative purposes, the metal band 384 is shown as a single cylindrical band that extends partway around the interior of the skirt 42. However, alternative configurations and locations of the metal band 384 are contemplated. For example, the metal band may include multiple different metal elements. The metal band in alternative examples may be attached to any portion of a component that is rotationally fixed to the skirt 42 during dose delivery, such as the flange 38 or the dial member 32. The metal band may include a metal element attached to the rotating member on the inside or outside of the member, or may be incorporated into such a member by metal particles incorporated into the component or by overmolding the component with the metal band. In the embodiment shown in FIG. 26, the dose button 56 of the device 10 shown is an integral part that combines both the skirt 42 and the dose button 56 of FIGS. 1-4. In this embodiment, the flange 38 is attached to the dose dial member 32 and cooperates with the clutch 52 to selectively couple the dose dial member 32 to the integral dose button 56. The radially outer surface of the integral dose button 56 presents a surface to the exterior of the body 11 for use in rotating the dial member 32 .

[0114] The dose detection system has been described using a particular design of a drug delivery device, such as a pen injector, as an example. However, the exemplary dose detection system may also be used with alternative drug delivery devices and with other sensing configurations that are operable in the manner described herein. Any of the devices described herein may include any one or more of the drugs described herein, such as within a cartridge of the device.

Claims

1. 1. A drug delivery system comprising: a drug delivery device having a housing, a dose setting member attached to said housing and rotatable relative to said housing during dose setting and / or dose delivery, and a sensed component rotationally fixed to said dose setting member; an actuator that is rotationally fixed to the dose setting member during dose setting; during dose delivery when an axial force is applied to the actuator, the actuator is not rotationally coupled to said dose setting member; The drug delivery system also includes an electronics assembly attached to the actuator, the electronics assembly comprising a processor and a plurality of rotation sensors operatively connected to the processor; said rotational sensors are rotationally fixed to said sensed component during dose setting, thereby rotating with said sensed component about an axis of rotation during dose setting and rotating relative to said sensed component during dose delivery, said rotational sensors being equiradially spaced in a ring-like pattern about said axis of rotation; the rotational sensors are configured to detect a characteristic of a sensed parameter of the sensed component corresponding to an angular position and / or angular movement of the sensed component relative to the rotational sensors during dose delivery to generate an output signal, and the processor is configured to receive the output signal for determining data representative of a delivered dose based on the output signal; A drug delivery system in which the sensed component has a unique angular profile for indicating a signal level change in output response as a function of the angular position of the sensed component, and this angular profile enables the angular position of the sensed component relative to the rotational sensor to be uniquely identified by the rotational sensor for any given angular position.

2. The drug delivery system of claim 1 , wherein the rotational sensor is a capacitive sensor, an inductive sensor, a magnetic sensor, or an optical sensor.

3. The drug delivery system of claim 1 , wherein the sensed component comprises one or more metallic elements.

4. The drug delivery system of claim 1 , wherein the sensed component is a metal band.

5. The drug delivery system of claim 4 , wherein the metal band extends around the axis of rotation and has a variable width.

6. The drug delivery system of claim 5 , wherein the metal band is formed to cover half of the circumference of the dose setting member.

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