Drug delivery devices and drug delivery assemblies
The drug delivery device addresses early feedback issues by incorporating a delay mechanism to ensure timely audible and tactile confirmation of drug delivery completion, improving user safety and reliability.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- SHL MEDICAL AG
- Filing Date
- 2024-04-12
- Publication Date
- 2026-05-13
AI Technical Summary
Existing drug delivery devices often provide audible feedback too early, indicating drug delivery completion before the process is fully finished due to manufacturing tolerances, leading to potential safety concerns.
A drug delivery device with a delay mechanism that includes a signal member and a delay mechanism, such as a threaded joint or friction-based mechanism, to ensure the audible signal is generated only after the drug delivery is complete, using a drive spring and a delay member to control the timing of the signal.
Ensures accurate and reliable audible, tactile, and/or haptic feedback at the right moment, confirming drug delivery completion, enhancing user safety and confidence.
Smart Images
Figure 2026514978000001_ABST
Abstract
Description
Technical Field
[0001] The present invention is in the field of drug delivery devices. More specifically, the present invention relates to an automated drug delivery device that provides audible, tactile, and / or haptic feedback to a patient using the drug delivery device. The present invention further relates to an assembly comprising such a device, pre-assembled with a drug container.
Background Art
[0002] Drug delivery devices for the automated delivery of drugs by self-administration are well known. In particular, the drug delivery device can be equipped to accommodate a drug container, for example, a drug container having a septum that is pierced immediately before use, or a syringe. Often, the drug delivery device and the drug container are pre-assembled to form a drug delivery assembly for self-administration.
[0003] Such drug delivery devices and drug delivery assemblies should generally be safe to use and easy to handle, and should reliably deliver a predetermined dose of the drug. From this perspective, it can be important for the patient to receive a feedback signal during and / or after delivery of the drug.
[0004] WO 2011 / 123024 discloses a drug delivery device for a syringe as a drug container, the drug delivery device providing audible, tactile, or visual confirmation to the patient when an injection is being made. For this purpose, the drug delivery device comprises a signal generating member that is an elongated U-bracket. The U-bracket can be displaced distally as soon as the plunger rod that displaces the plunger of the syringe reaches an end position. Then, a drive spring that displaces the plunger rod during delivery acts on the U-bracket and moves it distally until it hits the inner surface of the housing, resulting in the desired audible signal.
[0005] In practice, the timing of the audible signal can be a problem. Due to the required tolerance, it is practically impossible to ensure that the drug delivery process is completely finished at the exact moment the U-bracket becomes capable of displacing to generate an audible signal. Therefore, to safely ensure that confirmation is present in any case, the mechanism must be activated slightly before the drug delivery process is completely finished. Consequently, patients often hear the confirmation of drug delivery completion a little early. [Overview of the Initiative]
[0006] Therefore, an object of the present invention is to provide a drug delivery device that solves at least some of the shortcomings of the prior art. In particular, an object of the present invention is to provide a drug delivery device that improves the timing of audible signals.
[0007] These and other objectives are achieved by the present invention as defined in the appended claims, which are to be referenced herein.
[0008] In this disclosure, when the term "distal direction" is used, it refers to the direction away from the dose delivery site during use of the drug delivery device. When the term "distal part / end" is used, it refers to the part / end of the delivery device or its component that is furthest from the dose delivery site during use of the drug delivery device. Correspondingly, when the term "proximal direction" is used, it refers to the direction toward the dose delivery site during use of the drug delivery device. When the term "proximal part / end" is used, it refers to the part / end of the delivery device or its component that is closest to the dose delivery site during use of the drug delivery device.
[0009] Furthermore, the terms “longitudinal,” “longitudinally,” “axially,” and “axial” refer to the direction extending along the device or its components from the proximal end to the distal end, typically the direction of the longest extension of the device and / or components.
[0010] Similarly, the terms "transverse," "transversal," and "transversally" refer to a direction that is generally perpendicular to the longitudinal direction.
[0011] When it is stated that a component moves proximal, distal, axially in the proximal direction, axially in the distal direction, circumferentially, or in equivalent terms, it refers to movement relative to the housing of the injection device unless otherwise specified.
[0012] According to one aspect of the present invention, a drug delivery device for housing a drug container is provided.
[0013] Drug delivery devices are -Distal cap and, - Plunger rod and, - A signal member having a distal base and a plurality of arms extending proximal from the distal base along a plunger rod, - A drive spring that extends at least partially inside the plunger rod, having a proximal end that abuts against the proximal end bottom of the plunger rod and a distal end that abuts against the distal base of the signal member.
[0014] The signal member, plunger rod, and biasing member are at least partially housed within a cavity in the distal cap, which opens proximally.
[0015] The drive spring is compressed in its initial state, and a gap exists between the distal base of the signal member and the distal end wall of the cavity. The release of the drive spring is, - Move the plunger rod proximal to the distal cap, and apply the plunger rod to the drug container to release the drug from the drug container. - The signal component is moved distally relative to the distal cap.
[0016] The drug delivery device further includes a delay mechanism, the delay mechanism is -A rod extending from the distal end wall to the proximal end of the cavity, passing through the orifice of the distal base of the signal member, -At least in its initial state, the rod section is provided with a delay member housed within a gap.
[0017] If the drug container has a plunger or stopper, the plunger rod may act on the plunger or stopper, for example by moving proximal, to release the drug through the needle, and the needle may belong to the drug delivery device, or, for example, if the drug container is a syringe, it may belong to the drug container.
[0018] The delay mechanism delays the distal movement of the signal member. The delay mechanism prevents the signal member from receiving the acceleration that the drive spring would generate if it could move to the endpoint of its distal movement without any obstacles. Therefore, the delay mechanism means that the distal movement is somehow hindered / decelerated.
[0019] In the first embodiment, the rod comprises a first section having a male thread, and the delay member comprises a female thread that engages with the male thread, and during the release of the drive spring, the distal movement of the signal member rotates the delay member around the first section and moves distally along the rod to the distal end wall to produce an audible signal.
[0020] As the delay member advances, the threaded joint surface between the delay member and the rod rotates the delay member. At this time, the distal movement of the signal member causes the signal member to bias the delay member distally. This delays the distal movement. In this case, it is the delay member that strikes the distal end wall and generates an audible signal.
[0021] The delay mechanism can be configured to act in the first part of the distal movement and not in the second part of the distal movement. In other words, the distal movement can be delayed by the delay mechanism while the signal member travels along the first section of its displacement path, and may not be delayed along the second section thereof. Thus, the delay mechanism may comprise an obstructive means acting along the first section. Along the second section, the distal end wall of the distal cap can accelerate the signal member until it stops the signal member, in particular by means of a drive spring which also causes a proximal movement of the plunger rod, thereby generating an audible signal.
[0022] Thus, the rod may comprise a second section without a thread between the distal end wall and the first section.
[0023] The delay member may be a ring.
[0024] In a second embodiment, the delay member is an enlarged region of a section of the rod and during release of the drive spring, the distal movement of the signal member slides the orifice over the delay member in a manner to cause friction and moves the distal base distally along the rod to the distal end wall to generate an audible signal.
[0025] The enlarged region in this sense may be a widening feature, and thus the outer periphery of the rod perpendicular to the proximal-distal axis may be a feature enlarged compared to other parts. In the second embodiment, there is no substantial rotation of the delay member nor axial displacement of the delay member along the rod. The orifice can be made slightly smaller such that there is significant friction between the delay member and the orifice. Since the orifice is slightly smaller, a (slight) elastic deformation is required to effect the displacement movement. This causes a delay. The orifice sliding over the delay member can cause elastic deformation of the base unit and / or the delay member.
[0026] The delay member may be spherical and the orifice may be circular.
[0027] To increase resiliency, the signal member may optionally include a plurality of slits extending radially outwardly from the orifice.
[0028] Alternatively, the signal member may include a larger orifice (compared to the radial dimension of the delay member), the orifice having at least one inward-facing tang that is required to slide over the delay member during distal movement and that requires some elastic deformation of the tang.
[0029] The following refers to both the first and second embodiments.
[0030] In an initial state, the distal base of the signal member may contact the delay member.
[0031] The rod may extend partially within the drive spring.
[0032] The signal member may have the shape of a U-bracket, and at the proximal end of each arm, the signal member may have a flange-like support portion extending radially outwardly.
[0033] Specifically, the signal member and its operating principle may be of the type described in International Publication No. WO 2011 / 123024.
[0034] In an initial state (prior to distal movement), the signal member may extend along at least a substantial portion of the axial expansion of the plunger rod. For example, if the signal member has a plurality of arms extending from a distal base, the plunger rod may be at least partially received between the arms in the initial state. Thus, the arms extend along different sides of the plunger rod (e.g., both sides if two arms are present).
[0035] The signal member may include outwardly projecting support portions (e.g., one per arm) to ensure that the signal member is not pushed further into the cavity by the drive spring. For example, the support portions may be positioned immediately in the vicinity of the cavity opening and abut against the proximal end of the tubular portion.
[0036] An audible signal may be initiated when the plunger rod exits the space between the arms of the signal member, i.e., when the distal end of the plunger rod passes the proximal end of the signal member. In these embodiments, the position reached when the plunger rod exits the space between the arms of the signal member corresponds to the aforementioned distribution position of the plunger rod. In particular, the arms may be biased radially inward and pressed against the surface of the plunger rod. The arms are able to flex radially inward as soon as the plunger rod exits the space between the arms of the signal member, near the end of the process in which the drug is released. As a result, the outwardly projecting support portion is disengaged from the opening of the tubular portion, thereby allowing the signal member to be pushed further distally into the cavity against the resistance of the drug container, by the drive spring that biases the plunger rod proximal, thereby closing the gap. A delay mechanism then acts to delay this gap-closing displacement.
[0037] The distal cap may have a head portion with a distal end wall and a tubular portion with a cavity.
[0038] The distal cap, for example, together with the housing sleeve (and thus the tubular element of the housing), may form part of the housing of the drug delivery device. In addition to comprising the housing sleeve and / or distal cap, the housing may also comprise a container housing that is housed within the sleeve and provides a sheet for the drug container.
[0039] The drug delivery device may initially include a drive locking member that prevents the plunger rod from moving proximal, and when the drive locking member is activated, it ceases to prevent the movement and extends the drive trap.
[0040] Initial activation may be automatic, as is known from the prior art. For example, a drug delivery device may be equipped with a needle guard to protect the needle (of the drug delivery device or drug container for injecting the drug subcutaneously into the patient) after the proximal cap or the like has been removed immediately before use. Automatic release may occur when the patient presses the drug delivery assembly against the dose delivery site, causing the needle guard to displace distally against the biasing force. For this purpose, the drug delivery device may be equipped with a drive locking member that prevents the plunger rod from moving proximal before release. Release may be caused, for example, by rotation of the drive locking member, such rotation causing the needle guard to displace distally.
[0041] In addition to relating to drug delivery devices, the present invention also relates to drug delivery assemblies comprising drug delivery devices of the types described herein, the drug delivery assemblies being pre-assembled with drug containers, for example, drug containers having a diaphragm that is punctured by the needle of the drug delivery device before use, or with syringes having pre-assembled needles.
[0042] In general, all terms used in the claims should be interpreted according to their common meanings in the art unless otherwise expressly defined herein. All references to elements, devices, members, components, means, etc., should be openly interpreted as referring to at least one instance of such elements, devices, members, components, means, etc., unless otherwise expressly stated. [Brief explanation of the drawing]
[0043] Herein, embodiments of the present disclosure will be described with reference to the following accompanying drawings, merely as examples. [Figure 1]A diagram of one embodiment of a drug delivery assembly comprising a drug delivery device and a drug container. [Figure 2] Housing sleeve for drug delivery devices. [Figure 3] Needle guard for drug delivery devices. [Figure 4] The drug delivery assembly shown in Figure 1, with the proximal cap and needle cap assembly removed, the housing sleeve and needle guard absent, and the drug container and container housing clearly visible. [Figure 5] A subassembly of a drug delivery assembly comprising a plunger rod, a signaling member, a drive spring which is a biasing member, and a delaying member. [Figure 6] Subassembly of Figure 5 without the plunger rod. [Figure 7] Delay member. [Figure 8] Distal cap for drug delivery assembly. [Figure 9] A partial cross-sectional view of the partial subassembly of Figure 5, assembled with the distal cap, during two different stages at the end of the drug delivery process. [Figure 10] A partial cross-sectional view of the partial subassembly of Figure 5, assembled with the distal cap, during two different stages at the end of the drug delivery process. [Figure 11] A subassembly of an alternative embodiment of a drug delivery assembly, comprising a plunger rod, a signaling member, and a drive spring which is a biasing member. [Figure 12] A cross-sectional view of the subassembly in Figure 11, assembled with the corresponding distal cap. [Modes for carrying out the invention]
[0044] The drug delivery assembly 1 shown in Figure 1 comprises a drug delivery device and a drug container 3. The drug delivery device comprises a base unit having a housing, the housing comprising a housing sleeve 2 and a distal cap 5. The proximal cap 4, together with a needle cap assembly which optionally has at least one needle cap, protects the needle of the drug delivery assembly during transport and (short-term) storage.
[0045] Before use, the proximal cap 4 and needle cap assembly are removed.
[0046] Figure 2 shows the housing sleeve 2. The housing sleeve has a housing window 11 that allows the patient to see the drug container 3 to check its contents.
[0047] Figure 3 illustrates the so-called needle guard 10 (or "needle shield" or "needle cover"). Figure 4 shows the drug delivery assembly from Figure 1 with the proximal cap and needle cap assembly removed, and without the housing sleeve 2 and needle guard 10.
[0048] Therefore, the assembly shown in Figure 4, together with the needle guard 10 and housing sleeve 2, constitutes the drug delivery assembly immediately before use.
[0049] In the depicted embodiment, the base unit of the drug delivery device also includes a container housing 6 for housing a drug container, in addition to the housing sleeve 2 and distal cap 5. The container housing is, for example, transparent or has a window so that the patient can inspect the drug through the housing window 11. The container housing 3 in the depicted embodiment is a syringe equipped with a needle 23. Alternatively, the drug container may be a container equipped with a diaphragm that is punctured by a needle belonging to the drug delivery device before use.
[0050] The drug delivery device further comprises a drive locking member 26 (sometimes called a “rotor”) and a plunger rod, along with further elements which are described in more detail below. The plunger rod, together with further components which move with it where applicable, forms a drive unit.
[0051] As is known in the art, after the proximal cap and needle cap assembly are removed, the needle guard 10 is pushed by the needle guard spring 13 into a proximal position that protects the needle 23 of the drug delivery assembly.
[0052] To activate the system, the patient presses the drug delivery assembly shown in Figures 2-4, with the proximal cap and, if applicable, the needle cap assembly removed, against the dose delivery site, thereby displacing the needle guard 10 distally relative to the housing against the spring force of the needle guard spring 13. As a result, the needle 23 is exposed and can penetrate the patient's skin at the dose delivery site. Simultaneously, the needle guard 10 interacts with the drive lock member 26, causing it to rotate by a specific angle around the mesodistal axis 20 (see Figure 1). This movement releases the drive lock member 26 from the drive unit, allowing the drive unit to move proximal axially (release movement), thereby causing the plunger rod to act on the stopper 31 (or plunger) of the drug container. This activates drug delivery.
[0053] Several possible mechanisms exist in which the movement of an activation member (such as the needle guard 10) relative to the housing can activate drug delivery. The present invention does not depend on the nature of this activation and is therefore not described in further detail herein.
[0054] Figures 5 to 10 illustrate one embodiment from the first set of embodiments, which is a first example of how a delayed signal can be generated after drug delivery.
[0055] Figure 5 shows the plunger rod 41 together with the biasing member (drive spring 43 in this specification), the signal member 60, and the delay member 70.
[0056] Figure 6 shows the elements of Figure 5 without the plunger rod 41. Figure 7 shows a magnified view of the delay member 70. Figure 8 shows the distal cap 5. Figures 9 and 10 show cross-sectional views of the assembled elements of Figure 5 and the distal cap 5 at two different stages at the end of the drug delivery process.
[0057] The plunger rod 41 has the shape of a sleeve that is at least partially closed towards the proximal end by a proximal end bottom 45 that is pressed against the stopper 31 of the drug container during discharge. The drive spring 43 extends inside the plunger rod 41, with its proximal end in contact with the proximal end bottom 45.
[0058] The signal member 60 has the shape of a U-bracket, with a distal base 61 and two arms 62 extending proximally from there. At the proximal end of the arms 62, there is a flange-shaped support portion 63 that extends radially outward.
[0059] The distal cap 5 has a head portion 52 with a distal end wall 51. A tubular portion 53 having a cavity 54 that opens proximal is extended distally into the head portion 52, thereby the cavity is demarcated distally by the distal end wall 51 (see Figures 8 and 10). The distal cap further has a rod 56 extending proximal from the distal end wall. In the depicted embodiment, the rod 56 extends into the plunger rod 41 through an orifice in the distal base 61 of the signal member 60, thereby also functioning as a spring guide for the drive spring 43.
[0060] A portion of the rod 56 distal to the distal base 61 has a first section which is a threaded section with a male screw 57, and a second distal section which has a smooth surface and is not threaded.
[0061] The delay member 70 has a female thread 71. Together, the male thread 57 and the female thread 71 form a threaded joint surface between the rod 56 and the delay member. The leads of the male and female threads are relatively high, which allows the delay member 70 to advance rather than self-lock when subjected to axial force.
[0062] The drive spring 43 is in an energy-storing state in its initial configuration before the start of the release movement; that is, the drive spring is under tension by being compressed between the distal base 61 of the signal member 60 and the proximal end bottom 45 of the plunger rod 41. The support portion 63 of the signal member 60 is located proximal to the tubular portion 53 of the distal cap, thereby preventing the proximal end face 55 of the tubular portion from being further displaced distally into the cavity 54 by the spring force of the drive spring 43.
[0063] As soon as the drive locking member 26 (and / or other mechanism) ceases to prevent the plunger rod 41 from moving proximal due to activation by the user, the spring force of the drive spring 43 drives the plunger rod 41 proximal, causing a release movement that acts on the syringe stopper 31, releasing the drug through the needle 23. This proximal movement causes the plunger rod 41 to disengage from the space between the arms 62 of the signaling member 60.
[0064] The arm 62 of the signal member 60 is biased radially inward, thereby pressing the arm against the outer surface of the plunger rod 41. As soon as the distal end portion 46 of the plunger rod 41 passes the end portion 62 of the distal arm, the arm 62 becomes capable of bending inward. This disengages the support portion 63 of the arm from the proximal end face 55. This allows the signal member 60 to move distally by the spring force of the drive spring 43. The delay member 70 is initially in the proximal position, where it is in physical contact with or near the distal base 61. Therefore, after the support portion 63 disengages from the proximal end face 55, the drive spring 43 presses the signal member 60 against the delay member 70, rotating it and causing it to advance distally (see Figure 9). This produces the desired delay. Only after the engagement of the male thread 57 and the female thread 71 is released (see Figure 10), the signal member 60 can be accelerated together with the delay member 70 due to the spring force of the drive spring 43. The acceleration progressing along the second section of the displacement path causes the delay member 70 to strike the distal end wall 51 of the distal cap 5, producing a click that functions as an audible signal. Thus, the audible signal provides audible or acoustic feedback. It should be noted that the audible signal may also provide tactile and / or haptic feedback to the user. Thus, the distal end wall acts as a stopper structure for the signal member 60 via the delay member 70.
[0065] Figures 11 and 12 illustrate elements of one embodiment from the second group illustrating a second embodiment that generates a delayed signal after drug delivery. Figure 11 shows a plunger rod 41 having a drive spring 43 and a signal member 60, and Figure 12 shows a cross-sectional view of these elements assembled with a distal cap 5. Only the differences from the first embodiment are described.
[0066] In contrast to the first embodiment, the second embodiment does not have a dedicated delay member in the drug delivery device. Rather, the rod 56 of the distal cap 5 has an enlarged region 58, which, in the initial configuration, is located just distal to the distal base 61 before the support portion 63 of the signaling member 60 is disengaged from the proximal end face 55 of the distal cap 5. The orifice 64 of the distal base 61 through which the rod 56 extends is slightly smaller than the enlarged region 58.
[0067] Similar to Embodiment 1, the mechanism described above allows the signal member 60 to move distally by the spring force of the drive spring 43 as soon as the drive unit reaches the distribution position relative to the base unit. However, the expansion region 58 interferes with this distal movement. The distal base 61 of the signal member can slide over the expansion region only due to small elastic deformation of the signal member 60 (and / or potentially the expansion region 58) around the orifice 64, while the distal base 61 interacts with the expansion region 58 to generate sufficient friction to substantially delay the movement, but not to result in a complete interference fit.
[0068] After the distal base 61 slides over the enlarged area 58, the signal member 60 can move freely distally. During this movement of the distal base 61 along the second distal section of the rod 56, the signal member 60 is accelerated until the distal base 61 strikes the distal end wall 51 of the distal cap 5, producing a click that serves as a (delayed) audible signal.
[0069] Various other embodiments can be envisioned.
[0070] For example, in one embodiment of the first group of embodiments, the threaded joint surface does not require either a female thread (e.g., of a delay member) or a male thread (e.g., of a rod), as in the illustrated embodiment. Rather, it may suffice for either a female thread or a male thread to be present, but the cooperating element simply comprises at least one projection that engages with the female / male thread along the first section.
[0071] Furthermore, not all elements described herein are necessarily separate parts. For example, the container housing and housing sleeve, and / or the housing sleeve and distal cap, can be integrated as a single component.
[0072] Instead of being integrated with the distal cap 5, the rod, which also functions as a spring guide, can be a separate component.
[0073] Furthermore, the biasing member that stores energy for release movement is not necessarily a drive spring. For example, it could be a gas cartridge or another simple energy storage unit that can move the drive unit to release the drug.
[0074] The drug delivery devices described herein can be used for the treatment and / or prevention of one or more of many different types of diseases. Exemplary diseases include, but are not limited to, rheumatoid arthritis, inflammatory bowel disease (e.g., Crohn's disease and ulcerative colitis), hypercholesterolemia, diabetes (e.g., type 2 diabetes), psoriasis, migraine, multiple sclerosis, anemia, lupus, atopic dermatitis, asthma, nasal polyps, acute hypoglycemia, obesity, anaphylaxis, and allergies. Exemplary types of drugs that may be included in the drug delivery devices described herein include, but are not limited to, antibodies, proteins, fusion proteins, peptide bodies, polypeptides, PEGylated proteins, protein fragments, protein analogs, protein variants, protein precursors, and / or protein derivatives. Examples of drugs that may be included in the drug delivery devices described herein include etanercept (rheumatoid arthritis, inflammatory bowel disease (e.g., Crohn's disease and ulcerative colitis)), evolocumab (hypercholesterolemia), exenatide (type 2 diabetes), secukinumab (psoriasis), erenumab (migraine), alirocumab (rheumatoid arthritis), methotrexate (ametopterin) (rheumatoid arthritis), tocilizumab (rheumatoid arthritis), interferon beta-1a (multiple sclerosis), sumatriptan (migraine), and adalimumab (rheumatoid arthritis). Examples include, but are not limited to, the related disorders listed in parentheses. Pharmaceutical formulations, such as any of the drugs described herein, including but not limited to, darbepoetin alfa (anemia), belimumab (lupus), pegylated interferon beta-1a' (multiple sclerosis), sarilumab (rheumatoid arthritis), semaglutide (type 2 diabetes, obesity), dupilumab (atopic dermatitis, asthma, nasal polyps, allergies), glucagon (acute hypoglycemia), epinephrine (anaphylaxis), insulin (diabetes), atropine, and vedolizumab (inflammatory bowel disease (e.g., Crohn's disease and ulcerative colitis)). Pharmaceutical formulations, including but not limited to any of the drugs described herein, such as pharmaceutical formulations comprising the drugs listed herein (or pharmaceutically acceptable salts thereof) and pharmaceutically acceptable carriers, are also intended for use in the drug delivery devices described herein.A pharmaceutical formulation containing any of the drugs listed herein (or pharmaceutically acceptable salts thereof) may contain one or more other active ingredients, or may contain only one active ingredient.
[0075] Various modifications to the embodiments described are possible and will be conceived by those skilled in the art without departing from the present invention as defined by the following claims.
Claims
1. A drug delivery device for housing a drug container (3) that extends along the proximal-distal axis (20), - Distal cap (5), - Plunger rod (41), - A signal member (60) having a distal base (61) and a plurality of arms (62) extending proximal from the distal base along the plunger rod (41), - A drive spring (43) that extends at least partially inside the plunger rod (41), having a proximal end that abuts against the proximal end bottom (45) of the plunger rod (41) and a distal end that abuts against the distal base (61) of the signal member (60), The signal member (60), the plunger rod (41), and the biasing member (43) are at least partially housed within the cavity (54) of the distal cap (5), the cavity (54) opening proximally, the drive spring (43) is compressed in the initial state, a gap exists between the distal base (61) of the signal member (60) and the distal end wall (51) of the cavity (54), the release of the drive spring (43) causes the plunger rod (41) to move proximally relative to the distal cap (5), causing the plunger rod (41) to act on the drug container (3) to release the drug from the drug container, and causing the signal member (60) to move distally relative to the distal cap (5), The drug delivery device is a delay mechanism, - A rod (56) extends from the distal end wall (51) to the proximal side of the cavity (54) through the orifice (64) of the distal base (61) of the signal member (60), A drug delivery device characterized by comprising a delay mechanism, at least in the initial state, comprising delay members (70, 58) housed in the gap around a section of the rod (56).
2. The drug delivery device according to claim 1, wherein the rod (56) comprises a first section having a male screw (57), the delay member (70) comprises a female screw (71) that engages with the male screw (57), and during the release of the drive spring (43), the distal movement of the signal member (60) causes the delay member (70) to rotate around the first section and move distally along the rod (56) to the distal end wall (51) to generate an audible signal.
3. The drug delivery device according to claim 2, wherein the rod (56) has a second section without threads between the distal end wall (51) and the first section.
4. The drug delivery device according to any one of claims 1 to 3, wherein the delay member (70) is a ring.
5. The drug delivery device according to claim 1, wherein the delay member (58) is an enlarged region of the section of the rod (56), and during the release of the drive spring (43), the distal movement of the signal member (60) causes the orifice (64) to slide on the delay member (58) in a manner that generates friction, causing the distal base to move distally along the rod (56) to the distal end wall (51) to generate an audible signal.
6. The drug delivery device according to claim 5, wherein the delay member (58) is spherical and the orifice (64) is circular.
7. The drug delivery device according to claim 5 or 6, wherein the signal member (60) has a plurality of slits extending radially outward from the orifice (64).
8. The drug delivery device according to any one of claims 1 to 7, wherein in the initial state, the distal base (61) of the signal member (60) is in contact with the delay members (70, 58).
9. The drug delivery device according to any one of claims 1 to 8, wherein the rod (56) partially extends inside the drive spring (43).
10. The drug delivery device according to any one of claims 1 to 9, wherein the signal member (60) has the shape of a U-bracket, and at the proximal end of each arm (62), the signal member (60) has a flange-shaped support portion (63) that extends radially outward.
11. The drug delivery device according to any one of claims 1 to 10, wherein the distal cap (5) has a head portion having the distal end wall (51) and a tubular portion (53) having the cavity (54).
12. A drug delivery device according to any one of claims 1 to 11, comprising a drive locking member (26) that prevents the plunger rod (41) from moving proximal in the initial state, and when the drive locking member is activated, it stops preventing the movement and extends the drive trap.
13. A drug delivery assembly (1) comprising a drug delivery device according to any one of claims 1 to 12, and further comprising a drug container (3) assembled together with the drug delivery device.