US-12623025-B2 - Fixed dose injection device

US12623025B2US 12623025 B2US12623025 B2US 12623025B2US-12623025-B2

Abstract

A shield activated drug delivery device for delivering a plurality of fixed doses comprising a housing, a drive mechanism comprising a drive element (180, 280) adapted to rotate and thereby rotate and axially advance a piston rod (109, 209), wherein the drive mechanism is adapted to expel a dose of the plurality of fixed doses, in response to activation. The shield activated drug delivery device further comprises an activation mechanism, and a locking-and-resetting mechanism for releasably locking a shield in an activation position, in response to rotating the shield, and for inducing a rotational movement of the shield, in response to the drive element releasing a releasable lock.

Inventors

Bo Kvolsbjerg

Assignees

NOVO NORDISK A/S

Dates

Publication Date: 20260512
Application Date: 20201209
Priority Date: 20191218

Claims (14)

1 . A shield activated drug delivery device for delivering a plurality of fixed doses, the shield activated drug delivery device comprising: a housing assembly; a drive mechanism comprising a drive element adapted to rotate, in response to activation, and thereby rotate and axially advance a piston rod to expel a dose of the plurality of fixed doses, and wherein the drive element comprises a release structure for releasing a releasable lock during the rotation of the drive element; an activation mechanism adapted for activating the drive mechanism, wherein the activation mechanism, comprises: a shield and a connector operatively connected to the drive mechanism and adapted for connecting the shield with the drive mechanism, whereby the shield can activate the drive mechanism; a locking-and-resetting mechanism, wherein the locking-and-resetting mechanism is adapted (i) for forming the releasable lock between the connector and the shield, in response to rotating the shield from a first angular position, wherein the shield cannot move the connector in an axial direction for activation, to an activation position at a second angular position, wherein the shield can move the connector in the axial direction for activation, and (ii) for inducing a rotational movement of the shield from the activation position, in response to the activation of the drive mechanism whereby, the drive element releases the releasable lock, wherein the locking-and-resetting mechanism comprises: a return spring, a locking-and-resetting structure biased in the distal direction by the return spring, and adapted to engage the shield, whereby the shield is biased in a distal direction, and wherein the locking-and-resetting structure further comprises: a locking portion for releasably engaging a locking portion of the shield, and thereby establishing the releasable lock for locking the shield in the activation position, wherein the shield can move the connector in the axial direction and thereby activate the drive mechanism, and a resetting portion for engaging a resetting portion of the shield, wherein one or more of the resetting portion of the locking-and-resetting structure and the resetting portion of the shield comprises a helical portion for inducing the rotation of the shield under a force of the return spring, and thereby adapted for inducing the rotational movement of the shield, wherein the rotational movement of the shield is to be driven by the return spring, and whereby the shield is adapted to be urged away from the activation position.
2 . The shield activated drug delivery device according to claim 1 , wherein the connector is adapted for activating the drive mechanism during a proximal movement of the connector.
3 . The shield activated drug delivery device according to claim 1 , wherein, when the shield being in the first angular position, the shield is adapted to be prevented from moving the connector in a proximal direction, and thereby prevented from activating the drive mechanism.
4 . The shield activated drug delivery device according to claim 1 , wherein, when the shield being in the second angular position, the shield is further adapted for being changed from a distal position to a proximal position together with the connector, whereby the shield is adapted to move the connector in a proximal direction.
5 . The shield activated drug delivery device according to claim 1 , wherein an axial force transferred from the locking-and-resetting structure to the shield through the helical portion can induce a rotational and a distal movement of the shield.
6 . The shield activated drug delivery device according to claim 1 , wherein the resetting portion of the locking-and-resetting structure is adapted to engage the resetting portion of the shield, in response to rotating the shield from the first angular position to the activation position, whereby the helical portion is configured to induce a proximal movement of the locking-and-resetting structure against the force of the return spring, and whereby the locking portion of the locking-and-resetting structure and the locking portion of the shield of the established releasable lock are pressed against each other, in the activation position.
7 . The shield activated drug delivery device according to claim 1 , wherein the release structure is adapted to shift the engagement between the shield and the locking-and-resetting structure from the engagement between the locking portion of the locking-and-resetting structure and the locking portion of the shield to the engagement between the resetting portion of the locking-and-resetting structure and the resetting portion of the shield, and thereby release the releasable lock, in response to the release structure inducing a forced rotation between the locking portion of the locking-and-resetting structure and the locking portion of the shield.
8 . The shield activated drug delivery device according to claim 1 , wherein the shield activated drug delivery device is adapted: to be changed from, a non-activation state, wherein the shield is in the first angular position, to an activation state, wherein the shield is in the activation position, in response to turning the shield from the first angular position to the second angular position, wherein, when the shield activated drug delivery device being in the activation state, the releasable lock has been established, the locking portion of the locking-and-resetting structure and the locking portion of the shield are pressed together by the force of the return spring, and the shield is engaged with the connector, to be changed from the activation state to a dosing state, in response to moving the shield from the distal position to the proximal position, wherein, when the shield activated drug delivery device being in the dosing state, the shield is in the activation position, the drive element can rotate or be at an end of dose position, and the release structure can release the releasable lock in response to the rotation of the drive element, or in response to the drive element reaching the end of dose position, and to be changed from the dosing state towards the non-activation state, in response to the resetting portion of the locking-and-resetting structure engaging the resetting portion of the shield and inducing a rotational and distal movement of the shield, wherein the rotation and distal movement is driven by the return spring.
9 . The shield activated drug delivery device according to claim 1 , wherein the locking-and-resetting structure is integral with the connector, wherein the connector further comprises a release structure for being engaged by the release structure of the drive element during rotation of the drive element, wherein the release structure of the drive element is adapted to shift the engagement between the shield and the locking-and-resetting structure from the engagement between the locking portion of the locking-and-resetting structure and the locking portion of the shield to the engagement between the resetting portion of the locking-and-resetting structure and the resetting portion of the shield, and thereby release the releasable lock, in response to the release structure of the drive element engaging the release structure of the connector, and thereby inducing a forced rotation between the locking portion of the locking-and-resetting structure and the locking portion of the shield.
10 . The shield activated drug delivery device according to claim 9 , wherein the connector comprises an activation tab comprising a first transverse portion providing a proximal contact surface adapted for activating the drive element, and an axial portion providing the corresponding release structure for engaging the release structure of the drive element.
11 . The shield activated drug delivery device according to claim 9 , wherein the drive element comprises a tab protruding from an outer surface and providing a transverse portion providing a distally oriented surface portion for engaging the connector, in response to a proximal movement of the connector, and an axial portion providing the release structure of the drive element for engaging the connector and thereby releasing the releasable lock.
12 . The shield activated drug delivery device according to claim 1 , wherein the shield and the connector further comprise an axial portion when the shield being in the activation position, the axial portion of the shield further engages the axial portion of the connector, a relock tube, wherein the locking-and-resetting structure is integral with the relock tube, whereby the relock tube is adapted to engage and force the shield in the distal direction under the force of the return spring, wherein the shield comprises a radially extending guide structure engaging a step-wise helical track of the connector, whereby the force on the relock tube from the return spring is transferred to the connector through the shield, wherein the connector further comprises a corresponding release structure for cooperating with the release structure of the drive element, wherein the release structure of the drive element is adapted to shift the engagement between the shield and the locking-and-resetting structure from engagement between the locking portion of the locking-and-setting structure and the locking portion of the shield to engagement between the resetting portion of the locking-and-resetting structure and the resetting portion of the shield, and thereby release the releasable lock, in response to the release structure of the drive element engages the corresponding release structure of the connector, and thereby inducing a forced rotation of the connector and the shield, whereby relative rotation is induced between the locking portion of the locking-and-resetting structure and the locking portion of the shield.
13 . The shield activated drug delivery device according to claim 12 , wherein the relock tube is slidably arranged in the axial direction, and rotationally locked to the housing assembly.
14 . The shield activated drug delivery device according to claim 1 , wherein the shield activated drug delivery device is adapted for sequentially delivering the plurality of fixed doses by operating the shield.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 35 U.S.C. § 371 National Stage application of International Application PCT/EP2020/085205 (published as WO 2021/122192), filed Dec. 9, 2020, which claims priority to European Patent Application 19217339.1, filed Dec. 18, 2019 and to European Patent Application 19217333.4, filed Dec. 18, 2019; the contents of which are incorporated herein by reference. The present invention relates to a drug delivery device for delivering a plurality of fixed doses. In an aspect the invention relates to a shield activated drug delivery device for delivering a plurality of fixed doses. In a further aspect the invention relates to such a drug delivery device, wherein a mechanism prevents unintentional activation to avoid unintended double dosing. In a further aspect the invention relates to such a drug delivery device, wherein an initialization mechanism ensures initialization of the device. BACKGROUND OF THE INVENTION Drug delivery devices for self-administration of different liquid drug formulation presently exist in various shapes and sizes. Some are adapted for connecting to an infusion set, and some are connectable or integrated with an injection needle. The latter type is referred to as injection devices. Some are durable devices comprising a cartridge with a drug reservoir, wherein the cartridge can be changed. Others are disposable devices that are discarded when the cartridge is empty. Disposable devices can be either multi-dose devices, in which the user can set the desired dose size prior to each injection, or single dose devices, capable of administering only a single dose of a given size. The latter exists with so-called “Shield activation”, where the cannula is covered by a shield in the front of the device that releases the dose when pressed. The cannula is then exposed only to enter the skin, when the user presses the device against the skin, and thereby depresses the shield, and releases the dose. These injection devices are disposed after a single injection. Fixed dose devices are preferable to some users, since they may not feel comfortable with or be capable of operating the device to adjust the correct dose each time. When devices for instance are used by children or older people, simplicity and ease of use is important to avoid user error leading to over- or under dosing. In other cases, the treatment regimen prescribes a fixed dose of e.g. a GLP-1 type of drug. However, the device itself is responsible for a considerably part of the costs of the unit, not to mention the amount of materials used and thus necessary to dispose. It would therefore be desirable to make a fixed dose device capable of delivering multiple doses of a fixed volume. In existing multi-dose devices, the motor consists of a spring being wound up when adjusting the dose. One solution is to make a normal multi-dose device where the maximum dose size is limited, so it is only possible to dial up to the fixed dose size. This would however introduce a risk that the user does not dial up sufficiently and thus gets a smaller dose than expected, this problem has been solved in WO2020089167 filed by Novo Nordisk, wherein a ratchet tube is locked to the housing until the full dose has been set and the drive mechanism has been released. Another fixed dose device is disclosed in WO2019/09179 filed by Sanofi-Aventis. The disclosure relates to an injection device with a longitudinally displaceable dose tracker, providing an automated dose setting in accordance to a preselected size of a dose. The disclosed injection device comprises an elongated housing 10 extending along a longitudinal axis (z), a piston rod 20, 120 to operably engage with a piston 7 of a cartridge 6 filled with the medicament. The injection device further comprises a dose tracker 60, 150, 250, 350, 450, 550 selectively operably engageable with the piston rod 20, 120, wherein the dose tracker is proximally displaceable relative to the housing 10 from an initial position (i), see FIG. 25, towards at least a first activation position (a), see FIG. 26, for setting of the dose and wherein the dose tracker is distally displaceable relative to the housing (10) from the activation position (a) towards the initial position (i) for dispensing of the dose. The injection device comprises a spring 80, 144 to urge the dose tracker in the proximal direction. The injection device further comprises an interlock 84, 184, 284, 584 to lock the dose tracker in the initial position (i), and a release member 100, 101, 190, 290, 590 to release the interlock 84, 184, 284. For example, if the release member 190 is activated in order to liberate or to release the dose tracker 150 the dose tracker 150 starts to rotate relative to the housing under the action of the relaxing spring 144. An alternative fixed dose device wherein the size of the fixed dose can be selected is disclosed in WO 2017/106221 filed by Merch Sharp & Dohme Corp. However, enab