US-12623023-B2 - Drug delivery device and method to modify a drug delivery device

US12623023B2US 12623023 B2US12623023 B2US 12623023B2US-12623023-B2

Abstract

A drug delivery device is proposed, the drug delivery device comprising: a housing; a drive mechanism; a cartridge containing a drug, the cartridge being retained in a defined position relative to the housing, wherein the drive mechanism is configured to dispense the drug from the cartridge; a cartridge bias system, which comprises at least one resilient member and at least one rigid force transfer body, wherein the at least one rigid force transfer body is movably located within the housing, wherein the cartridge bias system is arranged and configured to exert a force on the cartridge to maintain the cartridge in the defined position, wherein the force is provided by the at least one resilient member, and wherein the at least one rigid force transfer body is operatively connected to the at least one resilient member such that the force is reacted by the at least one rigid force transfer body. Further, a method to modify a drug delivery device is disclosed.

Inventors

David Aubrey Plumptre
Robert VEASEY
Paul Griffin
Rory James Livingston Hawkins
Tom Alexander Earwaker

Assignees

SANOFI

Dates

Publication Date: 20260512
Application Date: 20190715
Priority Date: 20180718

Claims (16)

1 . A drug delivery device, comprising: a housing; a drive mechanism; a cartridge containing a drug, the cartridge being retained in a defined position relative to the housing, wherein the drive mechanism is configured to dispense the drug from the cartridge; and a cartridge bias system, which comprises at least one resilient member and at least one rigid force transfer body, wherein the cartridge bias system is arranged and configured to exert a force on the cartridge to maintain the cartridge in the defined position, wherein the force is provided by the at least one resilient member, wherein the at least one rigid force transfer body is operatively connected to the at least one resilient member such that the force is reacted by the at least one rigid force transfer body, wherein the cartridge is arranged in a cartridge holder which is connected to the housing, and wherein the cartridge bias system extends into the cartridge holder, and wherein the at least one rigid force transfer body is movable within the housing and is configured to be located at a position within the housing according to a length of the cartridge, and wherein a piston rod of the drive mechanism is arranged to travel through the at least one rigid force transfer body, wherein the housing comprises a piston rod guide section which is provided with a piston rod guide feature which cooperates with the piston rod to guide movement of the piston rod relative to the housing, wherein the piston rod guide section is radially offset from an inner surface of the housing, wherein at least a section of the at least one rigid force transfer body is arranged between an outer surface of the piston rod guide section and the inner surface of the housing, and wherein at least an inner surface of the at least the section of the at least one rigid force transfer body faces towards the outer surface of the piston rod guide section.
2 . The drug delivery device of claim 1 , wherein the at least one resilient member has a central opening, wherein an inner diameter of the central opening is greater than an outer diameter of the cartridge.
3 . The drug delivery device of claim 1 , wherein the at least one resilient member of the cartridge bias system comprises two resilient members.
4 . The drug delivery device of claim 3 , wherein the at least one rigid force transfer body is arranged in a load path between the two resilient members.
5 . The drug delivery device of claim 3 , wherein the at least one rigid force transfer body is arranged in a load path between the two resilient members and the cartridge.
6 . The drug delivery device of claim 3 , wherein one of the two resilient members is formed in a unitary body structure with the at least one rigid force transfer body.
7 . The drug delivery device of claim 3 , wherein one of the two resilient members is rigidly secured to the at least one rigid force transfer body.
8 . The drug delivery device of claim 1 , wherein the cartridge bias system has a housing contact area where the cartridge bias system contacts the housing and a cartridge contact area where the cartridge bias system contacts the cartridge, wherein the housing contact area and the cartridge contact area are radially and axially offset.
9 . The drug delivery device of claim 8 , wherein a distal surface of the at least one rigid force transfer body comprises the cartridge contact area.
10 . The drug delivery device of claim 8 , wherein a distal surface of the at least one resilient member comprises the cartridge contact area.
11 . The drug delivery device of claim 8 , wherein a radial distance between the cartridge contact area and the housing contact area is greater than or equal to 0.5 mm and less than or equal to 3.0 mm.
12 . The drug delivery device of claim 8 , wherein a radial distance between the cartridge contact area and the housing contact area is determined by a difference of a diameter of a 3.0 mL cartridge and a diameter of a 1.5 mL cartridge, and wherein an axial extension of the at least one rigid force transfer body is greater than or equal to a difference of a length of the 3.0 mL cartridge and a length of the 1.5 mL cartridge.
13 . The drug delivery device of claim 1 , wherein the drug in the cartridge is a medicament.
14 . The drug delivery device of claim 1 , wherein the outer surface of the piston rod guide section faces towards the inner surface of the housing.
15 . The drug delivery device of claim 1 , wherein the at least the inner surface of the at least the section of the at least one rigid force transfer body is radially separated from the outer surface of the piston rod guide section.
16 . An arrangement comprising: a first drug delivery device comprising: a housing, a first drive mechanism, a first cartridge containing a drug, the first cartridge being retained in a defined position relative to the housing, wherein the first drive mechanism is configured to dispense the drug from the first cartridge, and a first cartridge bias system, which comprises at least one resilient member and at least one rigid force transfer body, wherein the first cartridge bias system is arranged and configured to exert a force on the first cartridge to maintain the first cartridge in the defined position, wherein the force is provided by the at least one resilient member, wherein the at least one rigid force transfer body is operatively connected to the at least one resilient member such that the force is reacted by the at least one rigid force transfer body, wherein the first cartridge is arranged in a first cartridge holder which is connected to the housing, wherein the first cartridge bias system extends into the first cartridge holder, and wherein the at least one rigid force transfer body is movable within the housing and is configured to be located at a position within the housing according to a length of the first cartridge, and wherein a piston rod of the first drive mechanism is arranged to travel through the at least one rigid force transfer body, wherein the housing comprises a piston rod guide section which is provided with a piston rod guide feature which cooperates with the piston rod to guide movement of the piston rod relative to the housing, wherein the piston rod guide section is radially offset from an inner surface of the housing, wherein at least a section of the at least one rigid force transfer body is arranged between an outer surface of the piston rod guide section and the inner surface of the housing, and wherein at least an inner surface of the at least one the section of the at least one rigid force transfer body faces towards the outer surface of the piston rod guide section; and a second drug delivery device comprising a second cartridge, a second cartridge bias system, and a second drive mechanism, wherein the first cartridge and the second cartridge have different lengths and/or diameters, wherein the at least one rigid force transfer body of the first cartridge bias system compensates or is suitable to compensate differences in the different lengths and/or diameters of the first cartridge and the second cartridge.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application is the national stage entry of International Patent Application No. PCT/EP2019/068975, filed on Jul. 15, 2019, and claims priority to Application No. EP 18305980.7, filed on Jul. 18, 2018, the disclosures of which are incorporated herein by reference. TECHNICAL FIELD The present disclosure relates to a drug delivery device, in particular to an injection device, such as a pen-type drug delivery device and/or a pen-type injector. Furthermore, the present disclosure relates to an arrangement comprising two drug delivery devices. Also, the disclosure relates to a method of modifying a drug delivery device. BACKGROUND Often, in drug delivery devices a cartridge bias member such as a spring is provided which biases the cartridge to maintain the cartridge in a defined position relative to other elements of the device. This may ensure that accurate doses are delivered from the drug delivery device as the cartridge can be immobilized and does not move during setting and/or delivery of a dose. The cartridge bias member may be provided to account for manufacturing tolerances which cause small variations in the length of cartridges within the range of manufacturing tolerances, although the cartridges nominally should have the same lengths. SUMMARY Certain aspects provide improvements relating to cartridge bias system or arrangement which are used to bias cartridges in drug delivery devices. An aspect of the present disclosure relates to a drug delivery device. The drug delivery device comprises a housing. The housing may have a tubular shape, for example. The housing may be a sleeve. The drug delivery device further comprises a drive mechanism. The drive mechanism may be movably retained in the housing. The drive mechanism may comprise a piston rod, for example. The piston rod may be movable in the distal direction relative to the housing to dispense drug. The drug delivery device further comprises a cartridge which contains a drug or medicament, particularly an amount sufficient for a plurality of, preferably user-settable, doses. The cartridge may comprise a bung which may be driven distally with respect to a cartridge body of the cartridge in order to dispense drug or medicament which is retained in the cartridge, such as liquid drug or medicament, from the cartridge. The cartridge is expediently retained in a defined position relative to the housing. The drive mechanism may be configured to dispense drug from the cartridge. For example, distal movement of the piston rod may be transferred to the bung such that the bung is moved relative to the cartridge body in the distal direction. The drug delivery device further comprises a cartridge bias system. The cartridge bias system comprises at least one resilient member, such as only one resilient member or a plurality of resilient members such as two resilient members, and at least one rigid force transfer body, such as only one force transfer body or a plurality of force transfer bodies. The rigid force transfer body is preferably rigid at least against deformations in the axial direction. Accordingly, the rigid force transfer body may be used to transfer axial forces within the drug delivery device. The rigid force transfer body is movably retained in the housing. The force transfer body may be rotationally locked relative to the housing but axially movable relative to the housing. Alternatively, the force transfer body may be rotationally and axially movable relative to the housing. The axial movement of the force transfer body relative to the housing is preferably constrained, for example by a distal stop, which limits distal movement of the force transfer body relative to the housing, and/or a proximal stop, which limits proximal movement of the force transfer body relative to the housing. When the body abuts the respective stop further movement may be prevented in the distal or proximal direction. The cartridge bias system of the drug delivery device is arranged and configured to exert a force on the cartridge to maintain the cartridge in the defined position. The force is preferably provided by the resilient member. The force may be a distally directed force. The rigid force transfer body may be operatively connected to the resilient member and/or the cartridge such that the force is reacted by the force transfer body and/or transferred to the cartridge via the force transfer body. In other words, the rigid force transfer body may be arranged in the load path between the resilient member and the cartridge. For example, the rigid force transfer body may be arranged between the resilient member and the cartridge. The resilient member may be arranged proximally with respect to the force transfer body. The rigid force transfer body may be arranged proximally with respect to the cartridge. The cartridge bias system may be retained in the housing. Providing the rigid force transfer body in addition to the