End-of-injection signaling assembly for prefilled syringes

Abstract

To provide an injection terminal point signaling assembly for a prefilled syringe.SOLUTION: An injection terminal point signaling assembly includes: an elongated hollow syringe body 2 which has a proximal end 3 and a distal end; an injection needle which can be attached to the distal end of the syringe body; a fixed amount of an injectable material which is introduced to the syringe body; a plunger 8 which is configured and dimensioned to be inserted to the syringe body through the proximal end of the syringe body and a corresponding proximal opening 5; a displaceable electrical contact; and plunger travel lock means. The displaceable electrical contact forms an electrical contact simultaneously with engagement of the plunger travel lock means. The displaceable electrical contact establishes the electrical contact through the translational movement of an electrical contact applicator in a direction different from the injection travel direction from the first non-contact position where the electrical contact is not established to the second contact position where the electrical contact is established.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to pre-filled syringes and related technologies. In particular, the present invention relates to a signaling assembly for a pre-filled syringe that uses near field communication circuitry, commonly abbreviated as NFC. [Background technology]

[0002] Pre-filled syringe is known to those skilled in the art and is commonly used for administering various fixed doses or unit doses of substances, whether they are pharmaceuticals or other substances.For example, pre-filled syringe is generally used for administering drugs such as vaccines for immunization campaigns and programs, or for treating long-term conditions such as diabetes or other disorders that require the administration of fixed, pre-measured and stored doses of drugs, such as the anti-venom used to treat snake or spider bites, or for emergency injections for treating or developing other potentially life-threatening conditions such as acute pain or trauma, myocardial infarction, anaphylaxis, bacterial or toxic shock.Therefore, the use of pre-filled syringe is well known.

[0003] Such syringes generally include: an elongated hollow syringe body having a proximal end and a distal end, the elongated hollow syringe body having a first opening at the proximal end and a collar or flange at the proximal end around the first opening and projecting outside the hollow syringe body; an injection needle attached or attachable to a distal end of the hollow elongate syringe body, the injection needle closing a second opening of the hollow elongate syringe body at said distal end; a controlled amount of injectable material introduced into the hollow body; a plunger configured and dimensioned to be inserted into the hollow elongated syringe body through a proximal end of the hollow elongated syringe body and a corresponding proximal opening, the plunger having a plunger body with a stopper disposed at a distal end of the plunger body and a plunger head disposed at the proximal end of the plunger body; Equipped with.

[0004] One common problem with such prefilled syringes is being able to know when the syringe has actually been used, to avoid attempts at reuse or for tracking purposes, for example to know if and how much of an injectable substance has been administered from the prefilled syringe. To this end, various tracking systems are associated with such prefilled syringes to try to overcome this common problem.

[0005] For example, International Patent Application WO2014089086 describes a method for using an electronic medication device, such as an auto-injector, containing a medication such as epinephrine to treat anaphylactic shock. The device includes a sensor, an ID tag such as RFID, NFC, or other tag for short-range wireless communication such as Bluetooth, memory, a display, a speaker, a processor, and a communication interface. The processor interconnects one or more of the components, and the communication interface includes an interface for communication via Wi-Fi, a mobile carrier network, or satellite. The processor is configured to communicate with at least one remote system, such as a mobile phone, via the communication interface in response to the occurrence of an event, such as the administration of the medication or the expiration date of the medication. The sensor detects activation of the device and includes a frangible element that completes or destroys an electronic circuit when the device is activated. The sensor provides a signal to the ID tag to perform an action in response to use of the auto-injection device, and modifies the memory to indicate that the device has been used, along with a log of the time of use. The ID tag also provides information from the auto-injection device to a wireless reader of an NFC-enabled mobile device, such as a mobile phone. The cell phone uses RFID, NFC, or other wireless communication to read medication information printed on the automatic injection device or stored in the automatic injection device memory.

[0006] Similarly, U.S. patent application published as U.S. Patent No. 2019038840 discloses a prefilled syringe including a complex arrangement of two antennas: a first transmitting antenna configured to transmit a control signal to an external device; control electronics connected to the first transmitting antenna configured to provide instructions to the transmitting antenna to transmit the control signal; and a second bypass antenna positioned and configured to prevent the control electronics from providing instructions to the transmitting antenna when the bypass antenna is in an undisturbed position and enable the control electronics to provide instructions to the transmitting antenna when the bypass antenna is displaced from the undisturbed position. The complex arrangement of the two antennas and control electronics is integrated into the proximal end of the syringe plunger and covered by a push button. The bypass antenna is configured as a physically destructible electrical switch, and electrical contact is severed when the push button is pressed by the syringe user. Pressing the push button irreparably destroys the electrical contact to the bypass antenna, activating the primary antenna circuit and signaling the start of use of the syringe.

[0007] Both of these solutions are more concerned with the security aspect of, on the one hand, whether the pre-filled syringe still contains a usable drug, or, on the other hand, whether the injection device has been tampered with.None of these prior art documents address, or reliably address, the problem of knowing whether the provided unit dose of drug in the pre-filled syringe has been completely expelled or injected.This situation is known as the end point of injection. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2014089086 Brochure [Patent Document 2] U.S. Patent No. 2019038840 Summary of the Invention

[0009] Therefore, one object of the present invention is to provide an injection end point signaling assembly adapted and configured for use with a prefilled syringe as described above, wherein information regarding the injection end point can be signaled only when the syringe plunger not only reaches the end of the maximum distance of the defined possible travel within the hollow body of the syringe, but also ensures that all of the required units of the injectable substance, e.g., drug, initially contained therein are discharged before the injection is expelled from the syringe. Another object of the present invention is to provide such an injection end point signaling assembly, wherein signaling of the injection end point can only be possible when the syringe plunger is prevented from moving away from the end point position, for example, in a direction of travel substantially different from that normally required to expel the injectable substance, e.g., drug, during injection. Therefore, yet another object of the present invention is to provide such an injection end point signaling assembly, wherein both of the above-mentioned objects are simultaneously met.

[0010] These and other objects, as will become apparent from the present specification, are provided by an injection endpoint signaling assembly adapted and configured for use with a pre-filled syringe, the pre-filled syringe comprising: an elongated hollow syringe body having a proximal end and a distal end, the elongated hollow syringe body having a first opening at the proximal end and a collar at the proximal end around the first opening and projecting outside the hollow syringe body; an injection needle attached or attachable to the distal end of the hollow elongate syringe body, the injection needle closing a second opening of the hollow elongate syringe body at the distal end; a quantity of injectable material introduced into the hollow body; a plunger configured and dimensioned to be inserted into the hollow elongated syringe body through a proximal end of the hollow syringe body and a corresponding proximal opening, the plunger having a plunger body with a stopper disposed at a distal end of the plunger body and a plunger head disposed at the proximal end of the plunger body; Equipped with the injection end point assembly is configured to prevent injection end point signaling before the plunger reaches a limit of the injection travel tolerance; The injection endpoint assembly is further configured to enable signaling of the injection endpoint when the plunger reaches a limit of a tolerance range of the injection travel direction and is prevented from moving in a travel direction different from said injection travel direction.

[0011] As used herein, the expression "limits of tolerance in the injection travel direction" should be understood to refer to the maximum allowed, predetermined, and preconfigured travel length of the plunger within a hollow, elongated syringe body along the longitudinal axis of the syringe body. Generally, such maximum limit of tolerance in the injection travel direction is defined by both the length of the syringe body and the stopper located at the distal end of the plunger and in abutting contact with the inner surface of the syringe body at the distal end of the syringe body. When this occurs, little or substantially no injectable material remains within the syringe body. The predetermined or preconfigured limits of tolerance in the injection travel direction of the plunger relative to the injectable material within the syringe are themselves well documented and known to those skilled in the art.

[0012] Furthermore, the injection travel direction should be understood to refer to the direction in which the plunger travels during injection of the injectable substance. Generally, this travel direction is substantially or entirely distal to the distal end of the syringe body to expel the injectable substance, as is commonly known to those skilled in the art, which corresponds to the typical usage parameters of such pre-filled syringes.

[0013] As stated in the above objectives, the injection endpoint assembly is configured to prevent signaling of the injection endpoint before the plunger reaches the limit of the tolerance in the direction of injection travel. This expression should be understood to mean that the injection endpoint assembly is organized such that the establishment of an electrical connection that would allow charge or current to flow within the endpoint assembly is physically prevented until the plunger is moved to the maximum limit of injection travel, or in other words, when injection of the injectable substance must, to all intents and purposes, be completed. Several ways in which this can be achieved are described below as advantageous or preferred objects of the present invention.

[0014] Thus, according to one object, the above can be achieved by providing the end point signaling assembly with a displaceable or movable electrical contact configured to enable signaling of the injection point. Such displaceable electrical contact can take a variety of different forms, such as a simple switch mechanism, a biased or constrained conductive metal strip, or preferably a movable conductive surface. The displaceable or movable electrical contact is generally configured to be movable or displaceable from a first position within the injection end point signaling assembly, where no current can flow in the circuit with which the electrical contact interacts, to a second position within the injection end point signaling assembly, where electrical contact is made and allows charge or current to flow in the circuit with which the electrical contact interacts.

[0015] According to yet another object, preferably, the displaceable, i.e., movable, electrical contact establishes electrical contact via translational movement of the electrical contact applicator in a direction different from the injection travel direction from a first, non-contacting position where electrical contact is not established to a second, contacting position where electrical contact is established. The electrical contact applicator is a means for bringing or applying electrical contact to an electrical gap or electrically isolated region of an electrical circuit disposed within the injection endpoint signaling assembly, thereby closing the circuit and allowing current or charge to flow, for example, when current is applied to the circuit or the circuit is energized to pass current in the circuit.

[0016] According to a further object, preferably, the contact applicator is movable or displaceable via a translational movement substantially parallel to the longitudinal axis of the plunger. Alternatively, the electrical contact applicator can be moved or displaced by a rotational movement about the longitudinal axis of the plunger and / or by a combination of translational and rotational movements. In all of these variations, the displacement movement of the electrical contact applicator is in a different direction than the displacement movement in the injection travel direction, preferably in a direction substantially opposite to the injection travel direction. In most cases, this means that the electrical contact applicator moves in a proximal direction as opposed to a distal direction of the injection travel of the plunger.

[0017] In accordance with still further objects, the electrical contact applicator preferably comprises an electrically conductive surface. Such an electrically conductive surface may usefully comprise an electrically conductive material distributed within or on such surface by any of a variety of techniques known to those skilled in the art, such as, for example, chemically or physically, laminating, embedding, depositing, etching, engraving, doping, etc. In a particularly preferred embodiment, the electrically conductive surface disposed on the electrical contact applicator comprises carbon or metal particles. This electrically conductive surface forms an electrical contact when the applicator is moved into the appropriate position, and when not in the contact position, prevents the establishment of an electrical contact that would allow current or charge to flow within an electrical circuit disposed within the injection endpoint signaling assembly.

[0018] In accordance with yet another object, the contact applicator is located within the plunger head. While the contact applicator may be positioned and configured to function properly in virtually any location, it has been found to be particularly preferred to locate the electrical contact applicator within the plunger head, as this allows for both an overall reduction in size and even simplification of the electrical components included in the endpoint signaling assembly, particularly when circuitry is provided within or adjacent to the plunger head. Furthermore, translational and / or rotational movement of the electrical contact applicator can be limited to correspondingly short distances, improving the overall accuracy and precision of the device and reducing the risk of potential failure to establish sufficiently stable electrical contact.

[0019] According to another object, the injection endpoint signaling assembly comprises a plunger travel locking means configured to prevent the plunger from moving in a travel direction different from the injection travel direction when the limit of the tolerance of the injection travel direction is reached. The plunger travel locking means is designed and configured to prevent or substantially prevent a user from successfully moving the plunger in a direction different from the injection travel direction, for example, in the direction opposite or opposite to the injection travel direction. Applying excessive force to move the plunger, thereby potentially affecting the signaling provided by the injection endpoint assembly, would cause damage to the pre-filled syringe device to the extent that it would be unable to function again.

[0020] According to yet another object, the displaceable electrical contact makes electrical contact simultaneously when the plunger travel locking means is engaged. In other words, the various components of the injection endpoint assembly are arranged and configured such that the displaceable or movable electrical contact moves to a conductive position within the injection endpoint assembly, for example, within or adjacent the plunger head, simultaneously when the plunger travel locking means is activated or engaged to prevent the direction of travel within the plunger from differing from the direction of injection travel.

[0021] In accordance with yet another object, in a preferred embodiment, the plunger travel locking means comprises at least one radially outwardly projecting tine or a plurality of radially outwardly projecting tines connected to the plunger body. The projecting tines may be formed directly on the plunger body, for example, generally in a proximal region of the plunger body, or, equally preferred, may be indirectly connected to the plunger body via intermediate connection means.

[0022] According to yet another object and further preferred embodiments, the one or more radially outwardly projecting tines are connected to the plunger body via an elastically deformable arm or a corresponding plurality of elastically deformable arms. In such embodiments, the elastically deformable arms are preferably made of the same or similar material as the plunger body itself and can extend proximally from a distally located region of the plunger body toward the proximal end of the plunger body. The arms are elastically deformable or elastic in a generally radial direction, meaning that they can move toward or away from the plunger body in response to a radial force applied to them. This allows the arms to compress when, for example, a radial force is applied from around the outside of the plunger body, where such a radial force acts inward toward the plunger body, such as that applied by a syringe body made of a fairly rigid, inelastic material such as glass or polycarbonate, or other such crystalline or polycrystalline material known in the art, for example, when the plunger body is pushed through the syringe body during injection. The elastic deformation of the arms further allows the arms to move radially outward from the plunger body if a user attempts to reverse the plunger's direction of travel. When the arms connect radially protruding tines to the plunger body, attempts to withdraw the plunger body proximally from the syringe body cause these tines to move radially outward, forming a lock with either the syringe body and / or a region of the injection endpoint assembly configured to receive such tines.

[0023] According to yet another object, the injection endpoint signaling assembly further comprises a displacement means configured to engage with the contact applicator when the plunger moves in the direction of injection travel and to displace the contact applicator in a direction different from said injection travel direction. The displacement means is a means for displacing or moving the electrical contact applicator from a first, electrically non-contacting position to a second, electrically contact-established position. As explained below, various operational alternatives for providing such an arrangement are envisioned, with priority given to reliable and uncomplicated solutions.

[0024] Thus, for yet another purpose, the displacement means is at least partially disposed on or integrated into the collar of the hollow syringe body, for example, the displacement means can be separately fixedly positioned and disposed on the collar of the hollow syringe body, for example, by gluing or fastening the displacement means, or it can be directly integrated as part of the collar, for example during the molding process of the syringe body.

[0025] According to yet another object, the displacement means is preferably located on a syringe backstop removably attached to a collar on the hollow syringe body. The concept of a syringe backstop is described below. A syringe backstop generally enlarges the outwardly protruding collar of the syringe body, which has ergonomically shaped wings. One of the primary purposes of a syringe backstop is to facilitate syringe handling by increasing the area intended to accommodate the user's fingers. This is particularly useful when administering viscous substances or when the tissue into which the substance, e.g., a drug, is being injected creates resistance to the injection of the drug. Syringe backstops also facilitate syringe use by users with reduced mobility by providing a larger surface area for the user to grasp during injection. Most backstops sold today are made of plastic material and manually clip onto an outwardly protruding collar or finger flange on the syringe body, and are therefore typically molded to fit various known collar shapes. Such backstops are generally available under different trade names through companies such as Gerresheimer (Gx® backstops) and Becton Dickinson (BD backstops), to name two.

[0026] As described above, the displacement means may be disposed on the syringe backstop or may be directly integrated into or fixed to the collar of the syringe body, and the displacement means may comprise a raised, arcuate profile. In all variations, the displacement means is generally arranged so as to be elevated above the proximal surface of the collar or the proximal surface of the syringe backstop, thus providing a protruding surface that protrudes proximally from said surface. Preferably, the raised protruding surface is disposed on either the proximal surface of the collar or the proximal surface of the syringe backstop, coaxially about the longitudinal axis of the plunger. The raised profile may have various configurations, e.g., continuous or discontinuous regions of protrusion, and may be located in various geometric or non-geometric arrangements on the proximal surface of the collar or syringe backstop, and may be made of an elastomeric or resilient material, e.g., a silicone elastomer or another polymeric material with suitable elasticity and / or mechanical resistance to compression.

[0027] Preferably, the raised profile has a substantially arcuate shape. The substantially arcuate shape of the material comprising the displacement means may further comprise spurs protruding at regular or irregular intervals from the body of the arcuate material, giving the protruding surface a substantially serpentine appearance when measured along the longitudinal axis from the proximal end of the syringe. The protruding spurs facilitate positioning and rotational orientation of the plunger head about the longitudinal axis when the allowed injection travel limit is reached. Thus, the displacement means protrudes proximally in a fixed relationship with the syringe body collar or backstop. As the plunger head is moved distally during injection travel, it contacts the protruding raised profile of the displacement means as the plunger head begins near the end of its allowed travel distance. By continuing to advance the plunger head to its maximum allowed injection travel distance, the displacement means further engages the plunger head and translates the electrical contact applicator in a direction different from the injection travel direction, preferably parallel to the longitudinal axis of the plunger, from a first, electrically non-contacting position to a second position where electrical contact is established through application of a conductive surface to an insulating region or electrical gap of a circuit located within the plunger head. Closure of the electrical circuit allows current or charge to flow in the circuit, for example, if the circuit includes an energizable communication unit, such as a near field communication unit.

[0028] According to yet another object, the plunger travel locking means comprises at least one pair of cooperating opposing abutment surfaces, each of which includes a respective ridge of material, e.g., a raised annular portion of material which may be the same material as the material of the element or member to which it belongs, or the ridge of material may be added to the element in question, e.g., by gluing, welding, various other standard bonding methods, remolding, etc.

[0029] According to yet another object, the first cooperating abutment surface is located on an inner surface of the protruding wall of the syringe backstop, and the second cooperating abutment surface is located on an outer surface of the plunger head, preferably a plunger head cap that substantially covers the plunger head, as described in more detail below.

[0030] According to another object, the infusion endpoint assembly further comprises a wireless communication unit, such wireless communication units being known per se and often including one or more known technologies implementing various known communication protocols.

[0031] Exemplary wireless technologies are those covered by or implement standards such as IEEE 802.11a, b, g, n, ac, ax, also known as "Wi-Fi", cellular radio frequency communication protocols such as GSM, CDMA, GPRS, 3G, EDGE, 4G, W-CDMA, CDMA2000, HSPDA, LTE, 5G, low-power short-range wireless communications such as ZigBee, Bluetooth, TransferJet, IrDA, RFID, wireless USB, DSRC, near field communication (NFC), etc.

[0032] Therefore, according to yet another object, the wireless communication unit is a near-field communication (NFC) circuit. Near-field communication (NFC) technology, a derivative or evolution of RFID technology, is well known to those skilled in the art. It is described in detail in the international standards ISO / IEC 14443 and ISO / IEC 18000-3, the former of which defines the functionality of ID cards used to store information such as that found on NFC ID tags, and the latter of which defines RFID communications used by NFC-enabled devices. As indicated in the previous sentence, the basis of NFC is to be found in radio frequency identification, or RFID, technology, which provides appropriately equipped hardware for powering and communicating with unpowered, i.e., non-energized, passive electronic tags using radio waves.

[0033] Thus, the NFC circuit used in the present invention comprises a passive ID tag that stores a set of information such as, for example, the type of injectable substance, unit dose, concentration, expiry date, and any other useful or necessary information that can be suitably stored within the limitations of such an NFC ID tag. The NFC circuit also comprises appropriate and corresponding communication components that typically allow the NFC circuit to exchange said information with another NFC-enabled device, such as a smartphone, when energized. An antenna is also provided, forming part of the NFC circuit, to capture radio waves at a given functional frequency of the NFC protocol and thereby energize the circuit.

[0034] According to another object, preferably, the near-field communication circuit is located within the plunger head. Preferably, the near-field communication circuit can be energized only when electrical contact is established. From the above description of the functions of the NFC circuit and the contact applicator, it can be easily understood that the contact applicator is configured so that no energized charge can flow within the NFC circuit unless the contact applicator establishes electrical contact within the communication unit, thereby preventing signaling, communication, or exchange of NFC ID tag information with other NFC-enabled devices. In this manner, the communication unit of the assembly according to the present invention remains inactive or disabled until the contact applicator is in the appropriate position and electrically closes the NFC circuit. For example, if the contact applicator has a conductive surface, the NFC circuit can communicate data only when the conductive surface of the contact applicator is positioned to electrically close the circuit, e.g., by surface-to-surface contact of the conductive surface with a gap or insulating area provided in the NFC circuit, thereby allowing charge to flow within the NFC circuit when the NFC circuit is energized. In all other circumstances, the switch remains open, and therefore no charge can flow within the NFC circuitry, and therefore, even if it were to accidentally become energized, no information from the ID tag could be communicated by the NFC circuitry to the NFC-enabled device.

[0035] According to another object, the injection endpoint signaling assembly further comprises a tamper-proof means configured to prevent tampering with the plunger head when electrical contact is established and when the plunger reaches the limit of its tolerance for injection travel direction. In most commercially available pre-filled syringes, the plunger head protrudes beyond the syringe body collar or backstop, if present, even when the injection is complete. This provides an opportunity for a user to attempt to forcibly reverse the normal plunger travel direction by pulling on the head or by applying proximal traction in the proximal direction. Therefore, the assembly is provided with a tamper-proof means to prevent such a scenario.

[0036] According to one object, the tamper-proofing means comprises a proximally protruding wall located radially outward of the displacement means about the longitudinal axis of the plunger. Preferably, the protruding wall has a proximal end that lies adjacent to or substantially flush with the proximal face of the plunger head when the plunger has traveled its allowable distance or injection travel length. Substantial alignment of the proximal end of the protruding wall with the proximal face of the plunger head prevents a user from exerting such proximal traction, whether accidental or intentional, and further prevents any rotation of the plunger head in a misguided attempt to detach it from the remainder of the syringe. Even more preferably, the proximal face of the plunger head is rounded at its periphery, further reducing the likelihood that a user will attempt to disassemble the endpoint signaling assembly.

[0037] According to another object, the plunger head extends radially outward from the plunger rod at its proximal end and is defined by a substantially circular plunger head plate having an annular wall extending proximally from a periphery of said plunger head plate to form a proximal well having a proximal opening, the height of the annular wall being sufficient to fully accommodate and position an electrical contact applicator and enable movement, for example, from an electrically non-contacting position to an electrical contacting position.

[0038] According to another object, a communication unit including an NFC circuit can be usefully integrated, for example, into a small printed circuit board of a size and dimensions suitable for fitting comfortably within or being integrated into a proximal plunger head cap. The proximal plunger head cap closes the well opening, for example, via a threaded joint that cooperatively engages with a suitably configured thread on the inner surface of a peripheral annular wall forming the well of the plunger head. Integration of the NFC circuit into the proximal cap can be achieved, for example, by appropriate molding around the NFC circuit, which is then inserted into the well in the plunger head using, for example, threads as described, or a snap-fit ​​or push-fit coupling between the cap and the well, with the cap having a peripheral annular wall that protrudes proximally from the cap and extends distally beyond the location of the plunger head plate. In other words, in such a configuration, the distally extending annular wall of the plunger head cap has a height greater than the height of the annular wall forming the plunger head well, and is adapted to abut against the proximal surface of the syringe backstop via the distal abutment surface of the distally extending peripheral annular wall when the allowed injection travel distance is reached.

[0039] Briefly, the injection endpoint assembly is designed to function as follows.

[0040] The plunger head cap, located above the hollow syringe body bore, houses a communication unit with the NFC circuit. This circuit is initially in an inactive state due to an electrical isolation or gap in the circuit. As a result, communication cannot be established between the injection endpoint assembly and the alignment device, and data cannot be passed from the NFC circuit until the electrical isolation or gap is overcome, re-establishing electrical contact and allowing charge to pass through the re-established circuit. Therefore, even if an NFC-enabled device approaches the plunger head, or vice versa, when the syringe approaches a compatible NFC-enabled device such as a smartphone, energizing the NFC circuit does not activate it. Therefore, if the circuit is open until electrical contact is established via the positioning of the contact applicator, communication of the information stored in the passive ID tag cannot occur.

[0041] When the prefilled syringe is used, the plunger head is pressed through the cap in a known manner, causing the plunger rod to move along the longitudinal axis of the hollow syringe body, injecting or expelling the injectable substance contained therein. When the plunger reaches the end of a predetermined allowed travel distance, the plunger head is locked in an injection end position by a resilient or resiliently deformable arm and radially protruding tines.

[0042] At the same time, when the plunger head contacts the displacement means, the displacement means engages and translates the electrical contact applicator proximally, so that when the plunger is in the locked position, the contact applicator is in electrical contact, closing a circuit and allowing charge or current to flow. Thus, if the NFC circuit is currently energized by another NFC-enabled device, such as by swiping a smartphone over the plunger head of the prefilled syringe, or vice versa, by swiping the plunger head of the prefilled syringe over a smartphone, communication of the information stored in the ID tag can occur, thereby signaling or otherwise indicating that the endpoint of the injection has been achieved.

[0043] In addition to the above-mentioned other objects, there is also provided a kit of parts adapted and configured to be used with the pre-filled syringe described herein, the kit of parts comprising the injection end point signaling assembly described and provided in the present application.Such a kit of parts allows the end point signaling assembly described herein to be adapted to multiple different pre-filled syringes according to any given manufacturer's specifications.

[0044] The present invention will now be further described in connection with the drawings, which are provided for the purpose of illustrating various embodiments of the invention. [Brief explanation of the drawings]

[0045] [Figure 1] 1 is a schematic perspective view of a pre-filled syringe equipped with an injection endpoint signaling assembly according to the present invention; FIG. [Figure 2] 2 is a schematic, partially cutaway view of the proximal end of the pre-filled syringe and injection endpoint signaling assembly according to FIG. 1. FIG. [Figure 3] 2 is a schematic cross-sectional view of the endpoint signaling assembly according to FIG. 1 attached to a pre-filled syringe in an initial ready-to-use position. [Figure 4] 1 is a schematic cross-sectional view of an injection endpoint signaling assembly according to the present invention at the start of injection; [Figure 5] 5 is a schematic enlarged cross-sectional view of the proximal end of the endpoint signaling assembly of FIG. 4. FIG. [Figure 6] 1 is a schematic cross-sectional view of an end-of-infusion signaling assembly according to the present invention at the end of the infusion; [Figure 7] 7 is a schematic enlarged cross-sectional view of the proximal end of the endpoint signaling assembly of FIG. 6. FIG. [Figure 8] 10 is a schematic cross-sectional view of an alternative locking means for an injection end-point signaling assembly according to the present invention in a position at the start of injection; FIG. [Figure 9] 10 is a schematic cross-sectional view of an alternative locking means for an end-of-injection signaling assembly according to the present invention in an end-of-injection position; FIG. [Figure 10] 10 is a diagram illustrating an alternative locking means for the injection endpoint signaling assembly of FIG. 8 at the start of injection. [Figure 11] 10 is a diagram illustrating an alternative locking means for the injection endpoint signaling assembly of FIG. 9 at the end of injection. DETAILED DESCRIPTION OF THE INVENTION

[0046] Referring now to the drawings, a prefilled syringe (1) is shown in Figures 1 and 3. The prefilled syringe (1) has an elongated, hollow syringe body (2) having a proximal end (3) and a distal end (4), with a first opening (5) at the proximal end (3) and a collar (6) or flange that projects outward from the hollow syringe body (2) at the proximal end (3) around the first opening (5). An injection needle (not shown), typically covered by a needle cap (not shown), is attached to the distal end (4) of the hollow, elongated syringe body (2) and closes a second, distal opening (7) of the hollow, elongated syringe body (2) at the distal end (4). A controlled amount of injectable material (not shown), such as a liquid or foam medication, is introduced into the hollow body (2) during assembly of the syringe components.

[0047] The plunger (8) is configured and dimensioned to be inserted into the hollow elongated syringe body (2) through the proximal end (3) and corresponding proximal opening (5) of the hollow syringe body (2), and the plunger (8) has a plunger body or rod (9) with a stopper (10) disposed at the distal end (11) of the plunger body (9). The stopper (10) may be connected to the plunger body (9) in a known manner, for example, by providing a threaded projection (12) at the distal end (11) of the plunger body (9) and a corresponding threaded bore (13) inside the stopper (10) at the proximal end (14). The plunger body (9) further has a plunger head (15) disposed at the proximal end (16) of said plunger body (9). The plunger (8) and syringe body (2) are substantially longitudinally aligned along a central longitudinal axis (17) of the syringe body (2).

[0048] The plunger head (15) has a substantially circular plate (18) extending radially outward from the proximal end (16) of the plunger body (9). A peripheral annular wall (19) is disposed on the plate (18) and extends proximally therefrom to form a well (20). The well is closed at its proximal end by a communication unit (21) comprising an NFC circuit, shown in the figures as a disk disposed at the proximal end of the peripheral annular wall (19) of the well (20).

[0049] A plunger cap or cover (22) closes the well (20) and covers both the well (20) and the communication circuitry (21), and the plunger cap (22) is provided with mating means (23A, 23B) to prevent the cap (22) from falling off or becoming detached from the well (20), such as a push-fit or snap-fit ​​coupling consisting of an annular groove (23A) on the inner surface of the distally projecting annular wall (24) of the cap (22) and a corresponding mating annular ridge (23B) on the outer surface of the peripheral annular wall (19) projecting from the plate (18) of the well (20).

[0050] The injection endpoint assembly further includes a backstop (25) disposed on the flange or collar (6) of the syringe body (2). Most commercially available backstops (25) include a disk-shaped body having a central opening adapted to receive the syringe body and configured to allow clip-fit ​​or push-fit of the backstop body onto the collar (6). To this end, the backstop typically includes a corresponding seating groove (26) and a shaped shoulder or other protrusion that allows the backstop (25) to properly fit onto a variety of differently shaped collars (6) depending on the type of syringe to which it is attached. In this example, the backstop (25) further includes a substantially annular peripheral wall (27) extending proximally from the backstop body and terminating at a proximal end (28), which is intended to function as a tamper-evident means, as described in more detail herein.

[0051] Also visible in Figures 1, 2, and 3 is the proximal surface (29) of the backstop (25) to which is attached or integral, e.g., by deposition or molding, a displacement means (30), illustrated here as a distally projecting raised profile (30). The raised profile (30) is substantially arcuate in shape about the central opening of the backstop body and, therefore, radially disposed about the longitudinal axis (17). The raised profile of the displacement means (30) in the illustrated example is substantially continuous, and may have spars (31A, 31B, 31C) projecting outwardly from the raised profile, giving the displacement means an overall serpentine shape.

[0052] The displacement means (30) serves the primary function of displacing an electrical contact applicator (32) disposed within the well (20) formed by the plate (18) and the peripheral annular wall (19). The electrical contact applicator (32) is a movable, preferably translatable, member, such as a disk or plate (33), coaxially aligned with the longitudinal axis (17). The disk (33) is attached to a central rod (34) aligned with the longitudinal axis (17), which is slidably disposed within a bore (35) extending proximally from the bottom of the plate (18) into the body (9) of the plunger (8). The dimensions of the rod (34) and bore (35) are configured such that the rod cannot slide freely within the bore; rather, the rod (34) must be constrained to move by the application of a force to allow it to slide within the bore (35). Central rod (34) also extends proximally above the proximal face of disc (33) to provide at least one proximal electrical contact surface (36), which may include a conductive layer, such as a layer of deposited carbon, or a conductive metal in elemental form or matrix of conductive material, deposited on or integral with the proximal face. If desired or appropriate, at least one alternative or additional electrical contact surface may optionally be provided at one or more peripheral locations radially positioned from central electrical contact surface (36) on corresponding protrusions extending proximally from disc (33).

[0053] In the first position, when the prefilled syringe is ready for use as in FIG. 3 or at the beginning of an injection as shown in FIGS. 4 and 5, the electrical contact applicator (32) is in a first, electrical contact-free position seated against the bottom of the well, with the rod (34) extending substantially into the bore (35) so that the distal end of the rod nearly contacts the proximal-facing surface of the distal end of the bore (35). Seating of the applicator (32) may be further provided by a protrusion (37) extending distally from the disk (33) through an opening (38) in the plate (18) in radially spaced relation to the rod (34). In this position, the distally facing protrusion (37) extending from the disk (33) is aligned with the raised profile of the displacement means (30) but is physically spaced from the displacement means.

[0054] The communication unit (21), which generally comprises a disk-shaped circuit board, a passive NFC circuit including an ID tag included on the circuit board, and antennas spirally distributed around the NFC circuit and positioned around the periphery of the circuit board, also has an electrical gap or insulating region on the distal surface of the circuit board, e.g., at a central location on the circuit board, axially aligned with both the longitudinal axis (17) and the electrical contact surface (36), or alternatively and / or additionally, on the periphery of the circuit board and aligned with alternative and / or additional electrical contact surfaces on proximally facing protrusions extending from the disk (33). In this initial, ready-to-use position shown in FIG. 3, or at the beginning of an injection shown in FIGS. 4 and 5, the circuit remains open, preventing charge or current flow in the circuit even in the presence of applied RF current, such as in the approach of a properly equipped smartphone with NFC circuitry.

[0055] Figures 3, 4, and 5 further illustrate the presence of a plunger travel locking means (39) on the plunger (9). The plunger travel locking means (39) comprises at least one radially outwardly projecting tine (40) or multiple radially outwardly projecting tines connected to the plunger body (9). The projecting tines can be formed directly on the plunger body, for example, in a generally proximal region of the plunger body, or, equally preferably, can be indirectly connected to the plunger body via an intermediate connecting means, such as an arm (41) as shown in the figures. The arm (41) is elastically deformable. In such an embodiment, the elastically deformable arm can be made of the same or similar material as the plunger body itself and can extend proximally from a distally located region, such as a shoulder (42) on the plunger body (9), toward the proximal end of the plunger body. The arms are generally radially elastically deformable or resilient, meaning that they can move toward or away from the plunger body in response to a radial force applied to them. As shown in Figures 4 and 5, at the start of an injection, the plunger body (9) is forced into the syringe body bore, and the relatively rigid walls of the syringe body compress the arms (41) radially inward toward the plunger body (9). Furthermore, the tines (40) contact proximally facing, inwardly angled surfaces (43) on the disk body of the backstop (25), which protrude at least partially beyond the collar (6) into the syringe body bore, forming a locking shoulder (44). This situation is particularly shown in Figure 5.

[0056] 6 and 7 show the relative positions of the components of the end-of-injection signaling assembly at the end of injection. As further injection pressure is applied, the plunger body (6) moves distally, and the resistance of the inwardly sloping shoulder (43) combined with the elastic deformation of the arm (41) causes the tines (40) to move radially inward through the deformation of the arm, thereby forcing the tines onto the inwardly sloping surface (43) of the locking shoulder (44) and into the bore of the syringe body. The tines (40) thus come into frictional contact with the inner wall of the syringe body.

[0057] The frictional contact between the tines 40 and the inner wall of the syringe body is generally sufficient to prevent withdrawal of the plunger body 9 if a retraction force on the plunger body 9 is applied in a direction opposite to the injection direction. However, to ensure that this cannot occur, a locking shoulder 44 formed by an inwardly inclined surface 43 that protrudes at least partially into the syringe body bore actively prevents the plunger from being withdrawn when the tines 40 abut against the protruding area of ​​the locking shoulder 44; the natural tendency of the resiliently deformable arms 41 to move the tines 40 radially outward only serves to enhance the locking effect. Thus, at the end of an injection, the assembly is essentially prevented or locked from moving in a direction different from the injection travel direction.

[0058] As the plunger body moves distally during injection, plate (18) of plunger body (9) simultaneously moves toward the raised profile of displacement means (30). With further injection travel, protrusion (37) extending distally through opening (38) comes into abutting contact with the raised profile of displacement means (30). Continued distal movement of the plunger exerts a force sufficient to overcome the resistance to the sizing effort of rod (34) and bore (35), causing protrusion (37), fixedly connected to disk (33) of electrical contact applicator (32), to move or translate the contact applicator from a first, non-contacting position in a direction opposite to the direction of injection travel toward a second position where an electrical connection is established in the communication circuit. When the plunger reaches the maximum extent of its allowable injection travel, the disc (33) is moved in the opposite direction by the interaction of the distal projection (37) with the raised profile of the displacement means (30), which is sufficient to bring the conductive contact surface (36) into contact with an electrically insulating region or gap in the circuit, thereby closing that circuit.

[0059] Thus, in this second position, both electrical contacts are established in circuit, and the endpoint signaling assembly is locked in place, preventing accidental or intentional displacement of both the plunger (8) and the electrical contact applicator (32). By closing the circuit, the passive NFC circuit can function when energized by an appropriate external radio frequency, such as when an NFC-enabled device, e.g., a smartphone or tablet or other NFC reader, is brought sufficiently close to the plunger head (15), or vice versa, when the plunger head (15) of a now-empty syringe is brought close to such an NFC-enabled device. Energizing the passive NFC circuit in this manner enables signaling, allowing data stored in the NFC circuit's ID tag to be read, thereby properly signaling the injection endpoint to the NFC-enabled device.

[0060] As is apparent from the various figures, the distally projecting annular wall (24) of the plunger head cap (21) extends distally beyond the level or position of the plunger head plate (18). This extra distance is provided in the injection end-point signaling assembly and is particularly suitable for use in the alternative embodiments of the locking means shown in Figures 8, 9, 10 and 11. Like reference numerals are provided to indicate like objects in Figures 1 through 7.

[0061] Figures 8 and 10 depict the injection endpoint signaling assembly at the start of injection. Figures 9 and 11 depict the injection endpoint signaling assembly at the end of injection when the maximum allowable injection travel distance has been reached. Referring now to Figures 8 and 10, the most notable difference between the embodiments described with reference to Figures 1 through 7 is the absence of radially protruding tines and resiliently deformable arms on the plunger body. In the embodiment depicted by Figures 8 through 11, the plunger travel locking means is provided by at least a pair of opposing abutment surfaces located elsewhere, specifically a first abutment surface (45) on the inner surface (46) of the proximally protruding backstop wall (27). This first abutment surface is usefully provided via a ridge or raised portion of material, preferably the same material from which the proximally protruding wall of the backstop is formed, but may alternatively be a ridge of suitable resiliently deformable or elastic material added to said inner surface by, for example, welding, gluing, remolding, etc. In Figures 8 and 10, the ridge portion is located at or adjacent the distal end (47) of the distally projecting peripheral annular wall (24) of the cap (22). A second, opposing abutment surface (48) is provided on the outer surface of the cap (22), usefully via a ridge or raised portion of material that is preferably the same as the material from which the cap peripheral and distally projecting walls are made, but may alternatively be a ridge portion of suitable resiliently deformable or elastic material added to said outer surface, for example by welding, bonding, remolding, etc. In Figures 8 and 10, the second abutment surface (48) is located above the first abutment surface (45), but has a distally facing surface of the ridge portion in abutting contact with a proximally facing surface of the ridge portion of the first surface; this configuration prevents the cap from moving in a distal direction without the application of an appropriate force to move the cap in that direction.

[0062] During injection, a force is applied to the cap (22) in a proximal direction. If this force is applied sufficiently, for example, when a user presses the cap, the distal abutment surface of the ridged portion of the second abutment surface (48) overcomes the resistance opposed by the first abutment surface (45) and moves past the ridged portion of the first abutment surface, allowing injection travel. When injection is completed, the plunger and corresponding plunger head have reached the maximum allowable limit or distance of injection travel. As shown in FIGS. 9 and 11 , in this position, the second abutment surface (48) is located proximal to the first abutment surface. Furthermore, the proximal surface of the ridged portion of the second abutment surface (48) is in abutting contact with the distal surface of the ridged portion of the first abutment surface (45). The abutment surfaces prevent the plunger and cap from moving in a direction opposite to the injection travel direction, thereby locking the endpoint signaling assembly. The electrical contact applicator is moved in the same manner as described for Figures 1-7, meaning that at the end of injection, the electrical contacts close a gap or electrical insulation in the communication circuit, allowing signaling to occur by energizing the circuit by way of a suitably mounted energization device, such as a smartphone. Additionally, cap (22) has a proximal surface (49) adjacent to or flush with proximal end (28) of proximally projecting backstop wall (29) and may include rounded corners (50), which together act as a tamper-evident means to prevent attempts to grasp the plunger cap and apply proximal traction thereon.

Claims

1. 1. An injection endpoint signaling assembly adapted and configured for use with a pre-filled syringe, the pre-filled syringe comprising: an elongated hollow syringe body having a proximal end and a distal end, the syringe body having a first opening at the proximal end and a collar at the proximal end around the first opening and projecting outside the syringe body; an injection needle attached or attachable to the distal end of the syringe body, the injection needle closing a second opening of the syringe body at the distal end; a quantity of injectable material introduced into the syringe body; a plunger configured and dimensioned to be inserted into the syringe body through the proximal end and a corresponding proximal opening of the syringe body, the plunger comprising a plunger body having a stopper disposed at a distal end and a plunger head disposed at a proximal end; Equipped with said infusion endpoint signaling assembly comprising: a displaceable electrical contact configured to prevent signaling of an end of injection before the plunger reaches a limit of tolerance in the direction of injection travel and to enable signaling of an end of injection when the plunger reaches the limit of tolerance in the direction of injection travel; plunger travel locking means configured to prevent the plunger from moving in a travel direction different from the injection travel direction when the limit of the tolerance in the injection travel direction is reached; the displaceable electrical contact forms electrical contact simultaneously when the plunger travel locking means is engaged; An injection endpoint signaling assembly, wherein the displaceable electrical contact establishes electrical contact via translational movement of an electrical contact applicator in a direction different from the injection travel direction from a first non-contact position in which no electrical contact is established to a second contact position in which electrical contact is established.

2. 2. The injection endpoint signaling assembly of claim 1, wherein the plunger travel locking means comprises at least one radially outwardly projecting tine or a plurality of radially outwardly projecting tines connected to the plunger body.

3. 3. The injection endpoint signaling assembly of claim 2, wherein the one or more radially outwardly protruding tines are connected to the plunger body via an elastically deformable arm or a corresponding plurality of elastically deformable arms.

4. 4. An injection endpoint signaling assembly according to claim 2 or 3, wherein the plunger travel locking means comprises at least one pair of cooperating opposing abutment surfaces.

5. 5. The injection endpoint signaling assembly of claim 4, wherein the at least one pair of cooperating opposing abutment surfaces each comprise a ridged portion of material.

6. 2. The injection endpoint signaling assembly of claim 1, wherein the electrical contact applicator is displaceable via translational movement substantially parallel to a longitudinal axis of the plunger.

7. The injection endpoint signaling assembly of claim 1 , wherein the electrical contact applicator comprises a conductive surface.

8. The injection endpoint signaling assembly of claim 1 , wherein the electrical contact applicator is disposed within the plunger head.

9. 2. The injection endpoint signaling assembly of claim 1, further comprising a displacement means configured to engage with the electrical contact applicator when the plunger moves in the direction of the injection travel and to displace the electrical contact applicator in a direction different from the injection travel direction.

10. 10. The injection endpoint signaling assembly of claim 9, wherein the displacement means is at least partially disposed on or integrated into the collar of the syringe body.

11. 10. The injection endpoint signaling assembly of claim 9, further comprising a syringe backstop removably attached to the collar of the syringe body.

12. 12. The injection endpoint signaling assembly of claim 11, wherein the displacement means is disposed on the syringe backstop that is removably attached to the collar of the syringe body.

13. 10. The injection endpoint signaling assembly of claim 9, wherein the displacement means comprises a raised arcuate profile.

14. The displacement means comprising a raised arcuate profile; 13. The injection endpoint signaling assembly of claim 12, wherein the raised arcuate profile is disposed coaxially about the longitudinal axis of the plunger on either the proximal surface of the collar or the proximal surface of the syringe backstop.

15. An injection endpoint signaling assembly according to any one of claims 10 to 14, further comprising interference prevention means configured to prevent interference with the plunger head when electrical contact is established and when the plunger reaches the limit of the tolerance in the injection travel direction.

16. An injection endpoint signaling assembly as described in claim 15, which is dependent on claim 14, wherein the interference prevention means is located radially outside the displacement means around the longitudinal axis of the plunger and comprises a protruding wall protruding in the proximal direction.

17. 17. The injection endpoint signaling assembly of claim 16, wherein the protruding wall has a proximal end located adjacent to or substantially flush with a proximal face of the plunger head.

18. 17. The injection endpoint signaling assembly of claim 16, wherein a first cooperating abutment surface is disposed on an inner surface of the protruding wall of the syringe backstop, and a second cooperating abutment surface is disposed on an outer surface of the plunger head.

19. An injection endpoint signaling assembly according to any one of claims 1 to 18, wherein the injection endpoint signaling assembly comprises a wireless communication unit, the wireless communication unit being a near field communication (NFC) circuit and being disposed within the plunger head.

20. 20. The injection endpoint signaling assembly of claim 19, wherein the near field communication circuitry can be energized only when electrical contact is established.

21. 21. A kit of parts adapted and configured for use with a pre-filled syringe, comprising an injection endpoint signaling assembly according to any one of claims 1 to 20.

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