Drug delivery device with tamper-evident closure means

Abstract

A drug delivery device for administering a dose of a medicament by way of injection is disclosed, the device including a housing to receive a cartridge at least partially filled with a medicament and being sealed with a piston slidably disposed therein, a drive mechanism having a piston rod to be displaced in a distal direction to operably engage with the piston of the cartridge, a dose button operably engaged with the drive mechanism for at least one of preparing or initiating a dose dispensing action of the drive mechanism, and a protective member adapted to impede actuation of the dose button, wherein the protective member is releasably connected to the housing via a breakable seal.

Claims

1. A drug delivery device for administering a dose of a medicament by way of injection, the device comprising: a housing to receive a cartridge at least partially filled with a medicament and being sealed with a piston slidably disposed therein, a drive mechanism having a piston rod to be displaced in a distal direction to operably engage with the piston of the cartridge, a dose button operably engaged with the drive mechanism for at least one of preparing and initiating a dose dispensing action of the drive mechanism, and a protective member adapted to impede actuation of the dose button, wherein the protective member is releasably connected to the housing via a breakable seal, and wherein the protective member comprises a threaded section that mates with a threaded section of the housing such that the protective member is threadedly engaged with the housing in at least an initial configuration, wherein the seal comprises a first ring member and a second ring member, wherein the first ring member is positively engaged or frictionally engaged, integrally joined or firmly bonded to the housing in the initial configuration and the second ring member is positively engaged or frictionally engaged, integrally joined or firmly bonded to the protective member such that the first ring member and the second ring member are concentrically arranged with respect to each other, sharing a center in the initial configuration, and wherein the first ring member comprises a number of ring segments interconnected by predetermined breaking points and being individually connected to the second ring member, and wherein the first ring member disintegrates into the ring segments along the predetermined breaking points when the first ring member becomes subject to at least one of a radially directed force effect and an axially directed force effect.

2. The drug delivery device according to claim 1, wherein the first ring member is positively engaged with the housing and wherein the second ring member is integrally joined or firmly bonded to the protective member.

3. The drug delivery device according to claim 1, wherein the protective member is operably engaged with the housing.

4. The drug delivery device according to claim 3, wherein the protective member comprises a substantially cylindrical geometry.

5. The drug delivery device according to claim 3, wherein the protective member entirely covers the dose button arranged at a proximal end section of the housing in the initial configuration.

6. The drug delivery device according to claim 3, wherein a proximal end face of the protective member comprises a central through opening adapted to receive the dose button when the protective member is displaced into a release configuration in the distal direction relative to the housing.

7. The drug delivery device according to claim 6, wherein the diameter of the central through opening of the protective member is smaller than 10 mm.

8. The drug delivery device according to claim 6, wherein the proximal end face of the protective member flushes with a proximal end face of the dose button when in the initial configuration.

9. The drug delivery device according to claim 1, wherein the dose button is adapted to be depressed in the distal direction for dispensing of a dose of the medicament.

10. The drug delivery device according to claim 1, further comprising a pre-filled cartridge disposed therein.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following preferred embodiments of the invention will be described in greater detail by making reference to the drawings, in which:

(2) FIG. 1 schematically illustrates the outer appearance of a drug delivery device,

(3) FIG. 2 shows a cross section of a proximal end of the drug delivery device provided with a protective member according to a first embodiment,

(4) FIG. 3 shows another embodiment of a protective member releasably attached to the proximal end of the drug delivery device

(5) FIG. 4 depicts a breakable seal as used in the embodiment according to FIG. 3 in an isolated perspective illustration; and

(6) FIG. 5 depicts the breakable seal of FIG. 4 in an initial configuration where the first ring member and the second ring member are concentrically arranged with respect to each other and sharing a center.

DETAILED DESCRIPTION

(7) FIG. 1 schematically illustrates a drug delivery device 10 designed as a pen-type injector. The device 10 comprises a proximal housing component 12 as well as a distal housing component 14, the latter of which being releasably connected to the housing 12, either directly or by way of a cartridge holder section adapted to receive a cartridge comprising the medicament to be dispensed by the drug delivery device 10. Typically, the protective cap 14 protects the cartridge holder section, which is typically to be releasably connected with a needle assembly providing a fluid connection between the inner volume of the cartridge and biological tissue to be treated with said medicament.

(8) The proximal housing section 12 typically comprises a drive mechanism not further illustrated here. The drive mechanism comprises a displaceable piston rod to be operably engaged with a piston of the cartridge in order to expel a pre-defined amount of the liquid medicament from the cartridge. Dose setting and/or dose dispensing can be controlled by way of an actuation means 16 positioned at a proximal end section 15 of the drug delivery device 10.

(9) As indicated in FIGS. 1 and 2, the actuation means is surrounded and enclosed by a sleeve-like protective member 18. As illustrated in FIG. 2 in detail, the protective member 18 is threadedly engaged with the distal portion of the housing 12 by way of mutually corresponding threaded sections 34, 36. Moreover, in its initial configuration as depicted in FIG. 2, the sleeve-like protective member 18 comprises a radially inwardly directed flange portion 28 at its proximal end face which substantially flushes with a proximal end face of the actuation means 15, which, in the present embodiment comprises a dose button 16, that is adapted to be depressed in distal direction 32.

(10) In other words, the protective member 18 comprises a central through opening 29 with respect to a central axis 11. The size of the through opening 29 matches with the radial dimensions of the dose button 16.

(11) When transferring the protective member 18 in distal direction 32 towards a release configuration, which is indicated in FIG. 1, the actuation means 16 may protrude from the protective member 18. In such release configuration, the dose button 16 may be ready to be rotated or depressed according to the particular mechanical implementation of the drive mechanism.

(12) As further illustrated in FIG. 2, the seal 20 comprises at least a first ring member 22 positively engaged with the housing component 12. The ring member 22 is arranged in a circumferential recess or groove 26. Moreover, the first ring member 22 is integrally formed with the cylindrical sleeve of the protective member 18, which serves as a second ring member. First and second ring members 22, 18 are integrally formed by way of structurally weakened interconnecting portion 24.

(13) As soon as the protective member 18, hence the second ring member, is rotated with respect to the housing 12 it may experience a downward directed axial displacement in distal direction. As a consequence, the structurally weakened interconnection portion 24 may tear apart and the cylindrical portion 18 of the protective member may cover the first ring member 22, which stays in the circumferential recess 26. Even in case that the protective member 18 is returned to its initial configuration as illustrated in FIG. 2, an end-user may observe the broken seal 20, thus indicating, that the drug delivery device has already been in use.

(14) A distally directed displacement of the protective member 18 relative to the housing component 12 is stopped when the radially inwardly extending flange portion 28 of the protective member 18 gets in contact with the proximal end face 30 of the housing component 12, which serves as a stop face. When getting in contact with the stop face 30, the protective element 18 is still threadedly engaged with the housing component 12 and may therefore remain attached thereto.

(15) FIG. 3 illustrates an alternative embodiment, wherein a protective cap 38 is also threadedly engaged with a proximal end section of a housing 12 by way of mutually corresponding threads 54, 56. Here, the protective member 38 comprises a radially inwardly pointing shoulder portion 48 which is adapted to but against a proximal end face of the housing 12. The protective member 38 comprises a cupped geometry and has a closed bottom structure 50 entirely covering the actuation means 16 disposed underneath.

(16) In contrast to the embodiment according to FIG. 2, the protective member 38 is intended to be removed from the housing 12 by initiating an unscrewing motion.

(17) Hence, the protective member 38 is intended to be displaced in proximal direction 52 in order to give access to the dose button 16. The protective member 38 is mechanically engaged with the housing 12 by way another type of seal 40 being separately illustrated in FIG. 4.

(18) The seal 40 comprises a first ring member 42 and a second ring member 44. In the embodiment according to FIG. 3, the second ring member 44 is integrally formed or positively engaged with a distal end section of the sleeve-like protective member 38. The second ring member 42 in turn is positively engaged with the housing component 12. As illustrated in FIG. 4, the first ring member 42′ shown in a split-open configuration comprises three ring segments 43, which in an initial configuration are interconnected with their end sections 47, 49 facing towards each other. Each of the segments 43 of the first ring member 42′ is individually connected to the second ring member 44 by a joint 45.

(19) As indicated in FIGS. 3 and 4, the ring segments 43 comprise a somewhat triangular but open shape. With their free end section facing radially inwardly and in proximal direction 52, the ring segments 43 of the first ring member 42 positively engage with a groove or recess 46 provided at the outer circumference of the housing 12. In particular, the recess is designed as a kind of undercut 46.

(20) When the protective sleeve 38 is displaced in proximal direction 52 relative to the housing 12, a respective proximally directed force effect is transferred to the second ring member 44 and to the first ring member 42. As soon as the applied force exceeds a predefined threshold, predetermined breaking points or perforated and weakened structures interconnecting the three ring segments 43 of the first ring member 42 will start to tear apart the first ring member 42. Once the first ring member 42 is disintegrated into the various ring segments 43 as illustrated in FIG. 4, a clear indication is given, that the drug delivery device has been used.