Improvements in or relating to closed system transfer devices

Abstract

In the field of methods and device for administering medicaments there is a need for improved closed system transfer devices. A closed system transfer device (10) comprises a syringe (12) that has an elongate hollow syringe body (14) within which a plunger (16) is slidably received to define a medicament chamber (18) of varying size depending upon the degree of insertion of the plunger (16) within the syringe body (18). The closed system transfer device (10) also includes a needle assembly (28; 300) which has a needle assembly body (30) to which a hypodermic needle (32) is fixedly secured. The needle assembly body (30) is coupled with the syringe body (14) to retain an interior conduit (40) of the hypodermic needle (32) in fluid communication with the medicament chamber (18). In addition the closed system transfer device (10) also includes a shield assembly (42) that has a shield body (44). The shield body (44) is moveably coupled with the syringe body (14), whereby the shield assembly (14) is selectively operable to envelop the needle (32). The shield body (44) and syringe body (14) include mutually cooperable formations to constrain movement of the shield assembly (42) relative to the syringe (12) through a series of positions (200, 210, 220, 230, 240, 250, 260) corresponding to different operational states of the device (10).

Description

[0001] IMPROVEMENTS IN OR RELATING TO

[0002] CLOSED SYSTEM TRANSFER DEVICES

[0003] This invention relates to a closed system transfer device (CSTD) and to a method of using such a device.

[0004] Closed system transfer devices permit the compounding, transport, and administration of substances, principally medicaments, including potentially hazardous medicaments, while mechanically prohibiting both the transfer of environmental contaminants into the device and the escape of medicament or vapour concentrations thereof outside the device. Such devices specifically intended for medicament transfer are sometimes also known as closed system drug-transfer devices.

[0005] According to a first aspect of the invention there is provided a closed system transfer device comprising: a syringe having an elongate hollow syringe body within which a plunger is slidably received to define a medicament chamber of varying size depending upon the degree of insertion of the plunger within the syringe body; a needle assembly having a needle assembly body to which a hypodermic needle is fixedly secured, the needle assembly body being coupled with the syringe body to retain an interior conduit of the hypodermic needle in fluid communication with the medicament chamber; and a shield assembly having a shield body moveably coupled with the syringe body, whereby the shield assembly is selectively operable to envelop the needle, the shield body and syringe body including mutually cooperable formations to constrain movement of the shield assembly relative to the syringe through a series of positions corresponding to different operational states of the device.

[0006] The provision of shield and syringe bodies which have mutually cooperable formations that constrain relative movement between the shield assembly and the syringe through the aforesaid series of positions which correspond to different operational states of the device, advantageously helps to guide a user of the device through each of the operational states, and thus greatly improves useability of the device while reducing the risk of erroneous operation of the device.

[0007] Optionally the shield body is moveably coupled with the syringe body for linear movement in an axial direction along the length of the syringe body and rotational movement in a circumferential direction around an exterior of the syringe body. Such relative linear and rotational movement can be readily constrained while also providing a necessary distinction between each of the series of positions.

[0008] Preferably the series of positions includes two or more of: a first primary position corresponding to a compounding state of the device in which one or more medicaments can be drawn from a vial into the medicament chamber; a second primary position corresponding to a transport state of the device in which the shield assembly envelops the needle and movement of the shield assembly relative to the syringe is inhibited to prevent exposure of the needle beyond the shield assembly; and a third primary position corresponding to an administration state of the device in which the needle can be inserted into a recipient and some or all of the contents of the medicament chamber injected into the recipient.

[0009] Constraining relative movement between the shield assembly and the syringe to two or more of the first, second and third primary positions indicated, desirably allows a user to be guided through primary operational states of the device, i.e. the most significant and important operational states of the device, and thereby helps to ensure ready and reliable use of the device by such a user.

[0010] The position of the shield assembly relative to the syringe may be selectively restricted to a single one of the first, second or third primary positions.

[0011] Such restriction offers the opportunity to provide a simplified version of the device, limited in its mode of operation.

[0012] The mutually cooperable formations of the shield body and syringe body may be further configured to allow movement between the primary series of positions in only a single sequence.

[0013] Preferably the single sequence comprises the first primary position followed by the third primary position.

[0014] Optionally the single sequence comprises the first primary position followed by the second primary position followed by the third primary position. Such configurations of the mutually cooperable formations and restriction of relative movement through the series of primary positions to only a single sequence, forces a user through an optimal sequence of primary operational states for the device, and so further helps to ensure the device is used correctly by the user.

[0015] Preferably at least two primary positions are interposed by at least one unidirectional mutually cooperable formation.

[0016] The inclusion of at least one such unidirectional mutually cooperable formations desirably provides a respective mechanical barrier to unwanted movement between the respective primary positions in the wrong sequence. Such mechanical barriers, in turn, are both difficult (if not impossible) to overcome without permanently damaging the device, and also provide the option of conveying tactile and / or audible feedback to a user of the device when they have been correctly traversed.

[0017] In a preferred embodiment of the invention the series of positions further includes one or more of: a first secondary position corresponding to a shipping state of the device in which the shield assembly envelops the needle but is moveable towards the first primary position; a second secondary position corresponding to a ready state of the device in which the medicament chamber contains one or more medicaments while the shield assembly envelops the needle but is moveable towards the second primary position; a third secondary position corresponding to an inserted state of the device in which the needle is able to lie within a recipient; and a fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe.

[0018] A benefit of including a first secondary position corresponding to a shipping state of the device is that the needle is desirably enveloped, i.e. suitably encased or shrouded to prevent needlestick injuries during shipping of the device, e.g. from a manufacturer or distributor to an intended user of the device such as a medical operative or other healthcare professional, while the device is also ready for insertion into a medicament vial, e.g. while the shield assembly is also moveable into the first primary position corresponding to a compounding state of the device. Having a second secondary position that corresponds to a ready state of the device in which the medicament chamber contains one or more medicaments while the shield assembly envelops the needle, advantageously ensures enveloping of the needle, i.e. ensures the needle is suitably encased or shrouded to prevent needlestick injuries, while the shield assembly is ready to be moved towards the second primary position, i.e. the device is ready to adopt a transport state to permit safe and mechanically closed transportation of the device, e.g. from a compounding area to a patient administration area.

[0019] The inclusion of a third secondary position corresponding to an inserted state of the device in which the needle is able to lie within a recipient beneficially allows the device to adopt a configuration in which the needle is able to lie within a recipient while the shield assembly is able, continuously, to abut the recipient's body, e.g. during insertion of the needle, and thereby maintain mechanical closure of the device.

[0020] Including a fourth secondary position that corresponds to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe is particularly advantageous since it means that, e.g. following use of the device, i.e. following the injection of one or more medicaments from the medicament chamber into a recipient, the needle is completely and permanently disabled in a safe manner which prevents both needlestick injuries and reuse of the device.

[0021] In another preferred embodiment of the device, in which the series of positions includes the fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe, the shield assembly additionally includes a resiliently biased latch member which is urged into abutment with a tip of the needle when the shield assembly moves into the fourth secondary position relative to the syringe, whereby the mutually cooperable formations of the shield body and syringe body further cooperate with the latch member to inhibit linear movement of the shield assembly relative to the syringe.

[0022] Such inhibition of relative axial movement between the shield assembly and the syringe advantageously retains the shield assembly in an axial position relative to the syringe in which relative rotational movement between the shield assembly and the syringe is also inhibited, and thus the shield assembly becomes immoveable relative to the syringe. The mutually cooperable formations of the shield body and syringe body may be or include a male formation and a female formation.

[0023] Such an arrangement provides ready and reliable mutual cooperation in a form which is also readily manufacturable.

[0024] Optionally the male formation is or includes a resiliently biased pawl member and the female formation is or includes a plurality of slots into which the pawl member is biased

[0025] The inclusion of a pawl member provides a reliable follower element, while having a female formation in the form of a plurality of slots desirably allows for the provision of one or more pathways for the pawl to follow and thereby guide a user of the device through the series of relative positions between the shield assembly and syringe that correspond to respective operational states of the device.

[0026] In another preferred embodiment of the invention the female formation includes a first axially extending slot, a circumferentially extending slot extending from one end of the first axially extending slot, and a second axially extending slot intersected by an end of the circumferentially extending slot opposite the end coincident with the first axially extending slot.

[0027] Preferably one or more of: a first end of the first axially extending slot, being the end from which the circumferentially extending slot extends, defines both the first and second secondary positions; a second end of the first axially extending slot, opposite the first end, defines the first primary position; the second primary position lies along the circumferentially extending slot; a second end of circumferentially extending slot, being the end intersecting the second axially extending slot, defines the third primary position; a first end of the second axially extending slot, being the end nearest to an open end of syringe body, defines the third secondary position; and a second end of the second axially extending slot, being opposite the first end, defines the fourth secondary position.

[0028] The foregoing arrangements desirably allow for mapping of the various primary and secondary positions of the shield assembly relative to the syringe, and thus the ability to guide a user of the device to each of the corresponding operational states of the device.

[0029] The needle assembly may include an actuator module configured to selectively urge the shield assembly relative to the syringe from the third secondary position corresponding to an inserted state of the device in which the needle is able to lie within a recipient towards the fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe.

[0030] The inclusion of such an actuator module, and the urging it provides of the shield assembly from the third secondary position relative to the syringe towards the fourth secondary position relative to the syringe, advantageously helps to maintain the shield assembly in contact with a recipient's skin, e.g. during withdrawal of the needle following medicament administration, and thereby assists in mechanically prohibiting the escape of any hazardous medicament or vapour which might otherwise exit from the recipient or needle as it is withdrawn.

[0031] Optionally the actuator module includes an actuator valve moveable between a closed position in which a gas is held under pressure in a gas storage volume and an open position in which the gas is released from the gas storage volume to cause urging of the shield assembly from the third secondary position to the fourth secondary position.

[0032] Preferably movement of the actuator valve into the open position arranges the gas storage volume in fluid communication with a vent port to release the gas from the gas storage volume, the vent port in turn being arranged in fluid communication with a collapsible chamber sealingly fixed between the needle assembly and the shield assembly, whereby release of gas from the gas storage volume via the vent port into the collapsible chamber causes expansion of the chamber in an axial direction which thereby urges the shield assembly from the third secondary position towards the fourth secondary position.

[0033] The inclusion of such an actuator valve, and in particular the use of a pressurised gas to urge the shield assembly towards the fourth secondary position, i.e. the locked state of the device, desirably provides a suitable motive force for the shield assembly but one that progressively increases from an initial low level to a higher level so as to apply gentle urging with a degree of elasticity which accommodates potential oscillatory axial movement of the device, e.g. as it is withdrawn from a recipient by a medical operative, while nevertheless maintaining the shield assembly in contact with the recipient's skin. This is in contrast to solely mechanical actuators, such as springs, which typically have a much less forgiving mode of operation since they often transition from a high initial force to a lower one. Such mechanical actuators are also susceptible to mechanical creep over time which renders them less effective, and potentially unreliable, over time

[0034] Additionally, the provision of a progressively increasing motive force reduces the likelihood of any residual medicament being inadvertently displaced from the interior conduit of the device's needle as the shield assembly is urged towards the fourth secondary position, i.e. reduces the risk of medicament "splutter" as the device is transitioned into its locked state, something which has a tendency to otherwise occur in devices, e.g. retractable needle devices, with mechanical actuators that typically cause sudden motion and have much higher acceleration rates.

[0035] The actuator valve of the invention also permits ready tuning of the motive force applied to the shield assembly, both in terms of overall magnitude and rate of application, by modifying the stored enthalpy, i.e. the initial internal energy, of the pressurised gas.

[0036] Preferably the actuator valve is or includes a valve member slidably received within the needle assembly body and formed to define the gas storage volume.

[0037] Such a valve member configuration permits tuning of the gas storage volume size according to the requirements of the device and / or the characteristics of the gas held thereby.

[0038] Preferably the valve member itself defines the gas storage volume.

[0039] Having the valve member itself define the gas storage volume limits the number of sealing formations needed to maintain the sealing integrity of the gas storage volume, and so advantageously provides a commensurate reduction in the risk of leaking occurring via one or more such formations.

[0040] Additionally, a reduction in the number of sealing formations also desirably reduces the magnitude of force required to move, i.e. operate, the valve member against the resistance such sealing formations might otherwise impart. Optionally the valve member includes an exterior support formation having a hollow interior defining the gas storage volume.

[0041] Such an arrangement allows the valve member to provide the aforementioned benefits, while being readily manufacturable and the gas storage volume to be pre-filled once the needle assembly has been assembled.

[0042] The valve member may cooperate with the needle assembly body to define the gas storage volume therebetween.

[0043] Such an arrangement provides further options for tuning of the gas storage volume size.

[0044] In a further preferred embodiment of the invention the valve member includes first and second axially spaced sealing formations between which is formed an annular gas storage volume.

[0045] The provision of an annular gas storage volume provides further size-tuning options while additionally helping to ensure that the gas storage volume can readily be arranged in fluid communication with the or each vent port, e.g. upon movement of the actuator valve, i.e. the valve member, into its open position.

[0046] The actuator module may additionally include an elongate actuator member slidably received within the needle assembly body and fixedly secured to the actuator valve to move the actuator valve from its closed position to its open position, an end of the actuator member defining an abutment formation against which the syringe plunger is able to abut, whereby in the latter stages of insertion of the plunger within the hollow syringe body continued insertion of the plunger drives the actuator member in an axial direction and thereby causes movement of the actuator valve from its closed position towards its open position which, in turn, causes urging of the shield assembly from the third secondary position towards the fourth secondary position.

[0047] Having such an actuator member advantageously converts continued insertion of the plunger within the syringe body into opening of the actuator valve, and thus release of gas from the gas storage volume and the resulting urging of the shield assembly towards the fourth secondary position. Such an actuator member thereby desirably provides the option of harnessing continued operation of the device, e.g. the continued injection of a medicament into a recipient, to affect operation, i.e. opening, of the actuator valve, and thus further assists in ensuring that a correct sequencing of operational states of the device takes place.

[0048] Preferably the needle assembly body is moveably coupled with the syringe body and selective movement of the needle assembly body relative to the syringe body moves the actuator member abutment formation into the medicament chamber of the syringe.

[0049] Such movement of the needle assembly body relative to the syringe body selectively allows the abutment formation to desirably either lie outside the medicament chamber, e.g. while inadvertent or unwanted opening of the actuator valve is to be prevented, or be moved into the medicament chamber, i.e. for opening of the actuator valve to become possible, e.g. when operation of the actuator valve is desired. Such a feature therefore helps to ensure that the actuator valve is only armed, i.e. can only be operated, when desired and therefore helps to ensure safe and correct operation of the device.

[0050] The said selective movement of the needle assembly body relative to the syringe body may additionally move one or both of: (i) a bevelled opening plane lying coplanar with a bevelled opening of the hypodermic needle; and (ii) graduation markings, into alignment with a natural use axis of a flange defined by the syringe body.

[0051] Such alignment of the bevelled opening plane with the natural use axis of the flange beneficially ensures the bevelled opening is optimally orientated relative to the flange, so as to help a user correctly insert the needle into a recipient (in particular for subcutaneous injection) as the device moves between its administration and inserted states.

[0052] In another preferred embodiment of the invention the needle assembly body is helically coupled with the syringe body and constrained to be rotated by the shield body, whereby movement of the shield assembly from at least one of the second secondary position to the second primary position and the second primary position to the third primary position achieves one or more of movement of the actuator member abutment formation into the medicament chamber and movement of the bevelled opening plane and / or the graduation markings into alignment with the natural use axis of the flange.

[0053] Such a configuration advantageously coordinates, in an automatic manner, the sequencing of changes in device operational state with the arming of the actuator valve, and thus helps to ensure that movement of the actuator valve to its open position, and thereby subsequent urging of the shield assembly towards the fourth secondary position, can only take place when such operation is correctly intended.

[0054] Additionally it similarly coordinates, in an automatic manner, the sequencing of changes in device operational state with optimal orientation of the bevelled opening, i.e. chisel tip, of the needle relative to the flange in order to help a user correctly insert the needle into a recipient, and / or a desired orientation of graduation markings on the syringe body for easy reading by a medical operative, other healthcare professional, or any other user.

[0055] According to a second aspect of the invention there is provided a method of using a closed system transfer device according to any preceding claim comprising the step of moving the shield body relative to the syringe body between at least one position corresponding to an operational state of the device and another position corresponding to a different operation state of the device.

[0056] The method of the invention shares the benefit of corresponding features of the device of the invention.

[0057] It will be appreciated that the use of the terms "first" and "second", and the like, in this patent specification is merely intended to help distinguish between similar features, and is not intended to indicate the relative importance of one feature over another feature, unless otherwise specified.

[0058] Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, and the claims and / or the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and all features of any embodiment can be combined in any way and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner.

[0059] There now follows a brief description of preferred embodiments of the invention, by way of non-limiting examples, with reference being made to the following figures in which : Figure 1(a) shows an isometric view of a closed system transfer device (CSTD), according to a first embodiment of the invention, arranged in a shipping state;

[0060] Figure 1(b) shows a planar cross-sectional view of the CSTD shown in Figure 1(a);

[0061] Figure 1(c) shows an enlarged view of a portion of Figure 1(b);

[0062] Figure 1(d) shows an axial cross-sectional view through a circumferentially extending slot of a syringe body of a syringe forming a part of the CSTD shown in Figure 1(a)

[0063] Figure 2 shows an isometric view of the syringe forming a part of the CSTD shown in Figure 1(a);

[0064] Figure 3 shows a planar cross-sectional view through the syringe shown in Figure 2;

[0065] Figure 4 shows an axial cross-sectional view through the circumferentially extending slot of the syringe shown in Figure 2;

[0066] Figure 5 shows a first elevational view of the syringe shown in Figure 2;

[0067] Figure 6 shows a second elevational view of the syringe shown in Figure 5 rotated in a clockwise circumferential direction through 120°;

[0068] Figure 7 shows an isometric view of a first needle assembly forming a part of the CSTD shown in Figure 1(a);

[0069] Figure 8 shows a planar cross-sectional view of the first needle assembly shown in Figure 7;

[0070] Figure 9 shows a planar cross-sectional view of the first needle assembly shown in Figure 7 coupled with the syringe shown in Figure 2;

[0071] Figure 10(a) shows a planar cross-sectional view of a shield assembly forming a part of the CSTD shown in Figure 1(a);

[0072] Figure 10(b) shows a first isometric view of the shield assembly shown in Figure 10(a);

[0073] Figure 10(c) shows a second isometric view of the shield assembly shown in Figure 10(a);

[0074] Figure 11(a) shows a first isometric view of a seal formation forming a part of the shield assembly shown in Figure 10(a);

[0075] Figure 11(b) shows a second isometric view of the seal formation shown in Figure 11(a);

[0076] Figure 12 shows an isometric view of a seal member forming a part of the seal formation shown in Figures 11(a) and 11(b);

[0077] Figure 13(a) shows an isometric view of the CSTD shown in Figure 1(a) in a ready state; Figure 13(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 13(a);

[0078] Figure 13(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 13(a);

[0079] Figure 14(a) shows an isometric view of the CSTD shown in Figure 1(a) in a compounding state, prior to compounding;

[0080] Figure 14(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 14(a);

[0081] Figure 14(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 14(a);

[0082] Figure 14(d); shows an isometric view of the CSTD shown in Figure 1(a) in a compounding state, following compounding;

[0083] Figure 14(e) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 14(d);

[0084] Figure 15(a) shows an isometric view of the CSTD shown in Figure 1(a) in a transport state;

[0085] Figure 15(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 15(a);

[0086] Figure 15(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 15(a);

[0087] Figure 16(a) shows an isometric view of the CSTD shown in Figure 1(a) in an administration state;

[0088] Figure 16(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 16(a);

[0089] Figure 16(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 16(a);

[0090] Figure 17(a) shows an isometric view of the CSTD shown in Figure 1(a) in an inserted state, prior to administration;

[0091] Figure 17(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 17(a);

[0092] Figure 17(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 17(a);

[0093] Figure 17(d); shows an isometric view of the CSTD shown in Figure 1(a) in a inserted state, towards the end of administration;

[0094] Figure 17(e) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 17(d);

[0095] Figure 18(a) shows an isometric view of the CSTD shown in Figure 1(a) in a locked state Figure 18(b) shows an enlarged planar cross-sectional view of the CSTD shown in Figure 18(a);

[0096] Figure 18(c) shows an axial cross-sectional view through the circumferentially extending slot of the CSTD shown in Figure 18(a);

[0097] Figure 19(a) shows an isometric view of part of an actuator module forming a part of the CSTD shown in Figure 1(a), in an expanded configuration;

[0098] Figure 19(b) shows the actuator module shown in Figure 19(a) in a contracted configuration;

[0099] Figure 20 shows an axial view of the shield and needle assemblies forming a part of the CSTD shown in Figure 1(a);

[0100] Figure 21 shows an exploded, isometric view of parts of a second needle assembly which may alternatively form a part of the CSTD shown in Figure 1(a);

[0101] Figure 22(a) shows an isometric, partially sectioned view of the second needle assembly shown in Figure 21 with an associated actuator valve in a closed position;

[0102] Figure 22(b) shows an isometric, partially sectioned view of the second needle assembly shown in Figure 21 with an associated actuator valve in an open position;

[0103] Figure 23(a) shows an enlarged planar cross-sectional view of the second needle assembly shown in Figure 21 within a CSTD of the type shown in Figure 1(a), while in an inserted state, towards the end of administration; and

[0104] Figure 23(b) shows an enlarged planar cross-sectional view of the second needle assembly shown in Figure 21 within a CSTD of the type shown in Figure 1(a), while in a locked state.

[0105] A closed system transfer device (CSTD) according to a first embodiment of the invention is designated generally by reference numeral 10, e.g. as shown in Figure 1(a).

[0106] The device 10 includes a syringe 12 which has an elongate, hollow, syringe body 14 within which a plunger 16 is slidably received to define a medicament chamber 18, as shown in Figure 3 for example.

[0107] More particularly, the plunger 16 includes a piston end 20, which together with the hollow syringe body 14 defines the medicament chamber 18, as well as an actuator end 22 that along with a flange 24 at an open, proximal end 26 of the syringe body 14 can be used by a user of the device 10, e.g. a medical operative or other healthcare professional, to selectively insert the plunger 16 into the syringe body 14 or withdraw the plunger 16 within the syringe body 14 in a substantially conventional manner. The size of the medicament chamber 18, and hence the amount of a medicament (not shown in Figure 3), i.e. a drug, medicine or other substance that has a physiological effect when introduced to a human body, stored therein, varies depending upon the degree of insertion of the plunger 16 within the syringe body 14.

[0108] The device 10 also includes a first needle assembly 28, as shown in Figures 7 and 8, which has a needle assembly body 30 to which a hypodermic needle 32 is fixedly secured, e.g. by welding or other securing arrangement in a distal portion 34 of the needle assembly body 30.

[0109] The needle assembly body 30 is coupled, more particularly moveably coupled, and more particularly still in the embodiment shown, helically coupled, with the syringe body 14, e.g. as shown in Figure 9.

[0110] Such helical coupling is achieved via a female helical screw formation 36 formed within the needle assembly body 30, and a complementary male helical screw formation 38 formed on the syringe body 14. Different embodiments of the invention may be coupled in a different manner, however, and a male helical screw formation may be formed instead on the needle assembly body while the female helical screw formation may be formed on the syringe body, for example.

[0111] In any event, coupling of the needle assembly body 30 with the syringe body 14 retains an interior conduit 40 of the needle 32 in fluid communication with the medicament chamber 18.

[0112] In addition to the foregoing, the device 10 further includes a shield assembly 42, e.g. as shown in cross-section in Figure 10(a), which includes an elongate, hollow, shield body 44, as also shown in Figures 10(b) and 10(c).

[0113] The shield assembly 42 further includes a seal formation 46, as shown in Figures 11(a) and 11(b), that is fixedly secured to a distal end 48 of the shield body 44.

[0114] The seal formation 46 includes a seal member 50 which is mounted on a seal support body 52 which, in turn, is fixedly secured to the shield body 44.

[0115] The seal member 50 is formed of a flexible, resilient material, which may be an elastomer or a silicone rubber. The seal member 50 includes an orifice 54 formed therethrough and which, in the embodiment shown is located centrally within the seal member 50. The orifice 54 is self-sealing, i.e. it may be forced open by distorting the seal member 50, e.g. by pushing the needle 32 through the orifice 54, but when the seal member 50 relaxes from such distortion the orifice 54 closes.

[0116] Meanwhile, the seal support body 52 is formed from a substantially rigid material, such as a plastics material. It includes two, identical, tapered tab formations 56 each of which is slidable, during assembly of the shield assembly 42, through a complementary guide channel 58 formed in the shield body 44. Preferably the tab formations 56 and guide channels 58 are circumferentially spaced by 180 ° from one another, although this need not necessarily be the case.

[0117] A complementary securing formation 60, in the form of a resiliently deformable catch 62, is formed in the shield body 44 adjacent to a distal end of each guide channel 58 (only one of which catch 62 being shown, e.g. in Figure 10(b)). Upon sliding engagement of each tapered tab formation 56 with a corresponding catch 62 the seal support body 52 becomes fixedly secured to the shield body 44, i.e. in a snap-fit manner.

[0118] In the embodiment shown the orifice 54 forms a gas-tight seal when closed, and so the distal end 48 of the shield assembly 42 is mechanically closed, i.e. gaseously sealed, by the seal formation 46, subject to forced opening of the orifice 54, e.g. by the needle 32.

[0119] In addition to the foregoing, the shield body 44 is moveably coupled with the syringe body 14 in a manner that allows linear movement of the shield body 44 in an axial direction, i.e. in each of a proximal axial direction Ap and a distal axial direction AD, along the length of the syringe body 14, and also allows rotational movement in a circumferential direction, i.e. in each of a clockwise circumferential direction Ccwand a counter-clockwise circumferential direction Cccw, around an exterior of the syringe body 14.

[0120] More particularly, the hollow shield body 44 is sized to slide over the syringe body 14 in close-fitting alignment.

[0121] Such allowable movement of the shield body 44 relative to the syringe body 14 permits the shield assembly 42 to be selectively operable to envelop the needle 32, i.e. have the mechanically closed, gaseously sealed, distal end 48 of the shield assembly 42 selectively encase or shroud the needle, e.g. as shown in Figures 1(a) to 1(c). Such enveloping of the needle 32 helps to prevent both needlestick injuries and the ingress or egress of substances into / out of the device 10.

[0122] Additionally, the shield body 44 and the syringe body 14 include mutually cooperable formations 64, 66 that constrain movement of the shield assembly 42 relative to the syringe 12 through a series of positions which correspond to different operational states of the device 10.

[0123] More particularly, the shield body 44 includes a male formation 68, and more particularly still a resiliently biased pawl member 70, while the syringe body 14 includes a female formation 72 which includes a plurality of slots into which the pawl member 70 is biased.

[0124] Other embodiments of the invention (not shown) may include different mutually cooperable formations, and in such other embodiments the syringe body may instead include a male formation while the shield body may instead include a female formation.

[0125] Returning to the embodiment shown, the female formation 72 of the syringe body 14 includes: a first axially extending slot 74 which has a first end 76 and a second end 78, opposite the first end 76; a circumferentially extending slot 80 that extends from the first end 76 of the first axially extending slot 74, and which has a first end 82 coincident with the first axially extending slot 74, and a second end 84, opposite the first end 82; and a second axially extending slot 86 that is intersected by the second 84 end of the circumferentially extending slot 80, and which has a first end 88 that is nearest to the open, proximal end 26 of the syringe body 14, and a second end 90, opposite the first end 88 and lying beyond the circumferentially extending slot 80.

[0126] As indicated above, the mutually cooperable formations 64, 66, i.e. the pawl member 70 and combination of first axially extending slot 74, circumferentially extending slot 80, and second axially extending slot 86, into which the pawl member 70 is biased, of the shield body 44 and the syringe body 14 constrain movement of the shield assembly 42 relative to the syringe 12 through a series of positions that correspond to different operational states of the device 10.

[0127] More particularly, the series of relative positions and corresponding operational states of the device 10 are defined as follows. The first end 76 of the first axially extending slot 74 defines, i.e. when the pawl member 70 of the shield body 44 is positioned there, both a first secondary position 230 and a second secondary position 240.

[0128] The first secondary position 230 corresponds to a shipping state of the device 10, e.g. as illustrated in Figures 1(a) to 1(d), in which the shield assembly 42 envelops, i.e. covers and protects, the needle 32 but is moveable towards a first primary position 200 (described below). In the embodiment shown this means that the shield assembly 42 is moveable in an axial direction, and more particularly in a proximal axial direction Ap, relative to the syringe 12, although this need not necessarily be the case.

[0129] Meanwhile the second secondary position 240 is analogous to the first secondary position 230, but instead corresponds to a ready state of the device 10, e.g. as shown in Figures 13(a) to 13(c), in which the medicament chamber 18 contains one or more medicaments 92 (as evidenced by a substantial withdrawal of the plunger 16 within the syringe body 14 as shown, and as will be explained further in the context of use of the device 10), while the shield assembly 42 envelops the needle 32 but is moveable towards a second primary position 210 (described below). In the embodiment shown this means that the shield assembly 42 is moveable in a circumferential direction, and more particularly a clockwise circumferential direction Ccw, relative to the syringe 12, although again this need not necessarily be the case in other embodiments of the invention.

[0130] The second end 78 of the first axially extending slot 74 defines the first primary position 200 mentioned above that corresponds to a compounding state of the device 10, e.g. as shown in Figures 14(a) to 14(e), in which one or more medicaments 92 can be drawn from a vial 94 (shown schematically) into the medicament chamber 18, as will also be explained further in the context of use of the device 10.

[0131] The second primary position 210 mentioned above lies along the circumferentially extending slot 80, more particularly lies midway along the circumferentially extending slot 80, and more particularly still in the embodiment shown is spaced by 60 ° of circumferential rotation from each end 82, 84 of the circumferentially extending slot 80. In other embodiments of the invention (not shown) the second primary position may be positioned differently within the circumferentially extending slot 80. In any event, the second primary position 210 corresponds to a transport state of the device 10, e.g. as shown in Figures 15(a) to 15(c), in which the shield assembly 42 envelops the needle 32 and linear movement, i.e. movement in each of a proximal axial direction Ap and a distal axial direction AD, of the shield assembly 42 relative to the syringe 12 is inhibited to prevent exposure of the needle 32 beyond the shield assembly 42, again as will be explained further in the context of use of the device 10.

[0132] In the meantime, the second end 84 of the circumferentially extending slot 80 defines a third primary position 220 which corresponds to an administration state of the device 10, e.g. as shown in Figures 16(a) to 16(c), in which the needle 32 can be inserted into a recipient, e.g. patient, and some or all of the contents of the medicament chamber 18, i.e. the or each medicament 92 contained therein, can be injected into the recipient, which will also be explained further in the context of use of the device 10.

[0133] The first end 88 of the second axially extending slot 86 defines a third secondary position 250 which corresponds to an inserted state of the device 10, e.g. as shown in Figures 17(a) to 17(e), in which the needle 32 is able to lie within a recipient, as will be explained further in the context of use of the device 10.

[0134] Finally, the second end 90 of the second axially extending slot 86 defines a fourth secondary position 260 which corresponds to a locked state of the device 10, e.g. as shown in Figures 18(a) to 18(c), in which the shield assembly 42 envelops the needle 32 and is immoveable relative to the syringe 12.

[0135] To assist with rendering the shield assembly 42 immoveable relative to the syringe 12, the shield assembly 34, and more particularly the seal formation 46 thereof, additionally includes a resiliently biased latch member 96 which is urged into abutment with a tip 98 of the needle 32 when the shield assembly 42 moves into the fourth secondary position 260 relative to the syringe 12, e.g. as shown in Figure 18(b).

[0136] In such a fourth secondary position 260, the mutually cooperable formations 64, 66 of the shield body 44 and the syringe body 14, i.e. the pawl member 70 and the second end 90 of the second axially extending slot 86, cooperate with the latch member 96 to inhibit linear movement, i.e. movement in each of the proximal axial direction Ap and a distal axial direction AD, of the shield assembly 42 relative to the syringe 12. More particularly, abutment of the latch member 96 with the needle tip 98 inhibits movement of the pawl member 70 in a proximal axial direction Ap along the second axially extending slot 86 while abutment of the pawl member 70 against the second end 90 of the second axially extending slot 86 inhibits separation of the shield assembly 44 from the syringe 12, i.e. inhibits movement of the shield assembly 44 in the distal axial direction AD relative to the syringe 12.

[0137] As a consequence the pawl member 70 is trapped at the second end 90 of the second axially extending slot 86 where it cannot move in either a clockwise or counterclockwise circumferential direction Ccw, Cccw, and thus the shield assembly 42 is completely immovable relative to the syringe 12.

[0138] In the embodiment shown, the latch member 96 is disposed within the seal member 50 of the seal formation 46, e.g. as shown in Figures 10(a) and 12. Resilient biasing of the latch member 96 is provided by a biasing finger 100 protruding adjacent to the orifice 54 of the seal member 50, e.g. as shown in Figure 18(b), although other ways of biasing the latch member 96 are also possible.

[0139] In all the specified positions 200, 210, 220, 230, 240, 250 of the shield assembly 42 relative to the syringe 12, except the fourth secondary position 260 corresponding to the locked state of the device 10, the latch member 96 is displaced against the finger 100 by the needle 32, e.g. as shown in each of Figures 1(b), 1(c), 13(b), 14(b), 14(e), 15(b), 16(b), 17(b), and 17(e), and thus the needle 32 is able to freely move in an axial direction relative to the latch member 96.

[0140] Absent the influence of the needle 32, however, the finger 100 urges the latch member 96 into abutting engagement with the needle tip 98, i.e. as shown in Figure 18(b), and the device 10 thus adopts its locked state.

[0141] The latch member 96 is formed from a substantially rigid material such as a metal or a ceramic, although other materials are possible.

[0142] In addition to the foregoing, the mutually cooperable formations 64, 66 of the shield body 44 and syringe body 14, i.e. the pawl member 70 and the slots 74, 80, 86, are further configured to allow movement between the primary series of positions, i.e. the first, second and third primary positions 200, 210, 220, in only a single sequence, and more particularly in a single sequence comprising the first primary position 200, followed by the second primary position 210, followed by the third primary position 220.

[0143] In the embodiment shown the mutually cooperable formations 64, 66, i.e. the pawl member 70 and the slots 74, 80, 86, achieve such specific sequencing of the first, second and third primary positions 200, 210, 220 by interposing a first unidirectional mutually cooperable formation 102 between the first primary position 200 and the second primary position 210, and interposing a second unidirectional mutually cooperable formation 104 between the second primary position 210 and the third primary position 220, e.g. as shown in Figure 4.

[0144] More particularly, in the embodiment shown the first unidirectional mutually cooperable formation 102 lies between the first end 82 of the circumferentially extending slot 80 and the second primary position 210 (which itself lies within the circumferentially extending slot 80), although in other embodiments of the invention the first unidirectional mutually cooperable formation may lie elsewhere.

[0145] Similarly, in the embodiment shown the second unidirectional mutually cooperable formation 104 lies between the second primary position 210 and the second end 84 of the circumferentially extending slot 80, although other positioning is also possible.

[0146] Preferably the first primary position 200 and the second primary position 210 are circumferentially spaced from one another along the circumferentially extending slot 80 by a first angle a, which in the embodiment shown is 60° (although this may be any other angle, such as, e.g. 90° or 120°), and the second primary position 210 and the third primary position 220 are circumferentially spaced from one another along the circumferentially extending slot 80 by a second angle , which in the embodiment shown is also 60° (although again this may be any other angle, such as e.g. 90° or 120°).

[0147] Additionally, the first and second unidirectional mutually cooperable formations 102, 104 preferably take the form of respective first and second ratchet teeth 106, 108, each of which is shaped to allow movement of the pawl member 70 in a clockwise circumferential direction Ccw within the circumferentially extending slot 80 but inhibit movement of the pawl member 70 in a counter-clockwise circumferential direction Cccw Other forms of first and second unidirectional mutually cooperable formations are possible, however. In addition, the first needle assembly 28 in the embodiment shown and described hereinabove, includes a first actuator module 110 which is configured to selectively urge the shield assembly 44 relative to the syringe 12 from the third secondary position 250, that corresponds to an inserted state of the device 10, towards the fourth secondary position 260 which corresponds to a locked state of the device 10.

[0148] More particularly, the first actuator module 110 includes a first actuator valve 112 that is moveable between a closed position, e.g. as best shown in Figure 8, in which a gas (not shown) is held under pressure in a first gas storage volume 114, and an open position, e.g. as shown in Figure 18(b), in which the gas storage volume 114 is arranged in fluid communication with first and second mutually opposed vent ports 116, 118 in the needle assembly body 30 to release the gas from the gas storage volume 114. Other embodiments of the invention may include fewer than or more than two vent ports.

[0149] Preferably the gas is a hydrofluoroalkane, such as Solkane®, although this need not necessarily be the case, and other propellants (which may not be a gas) can also be used.

[0150] In the embodiment shown the first actuator valve 112 takes the form of a first valve member 120 that is slidably received within the needle assembly body 30, i.e. within a hollow interior 122 of the needle assembly body 30 through which the needle itself also passes. The first valve member 120 and the needle assembly body 30, i.e. the hollow interior 122 thereof, cooperate with one another to define the first gas storage volume 114 therebetween.

[0151] More particularly still, in the embodiment shown the first valve member 120 includes first and second axially spaced sealing formations 124, 126 between which is formed an annular first gas storage volume 114. The first and second sealing formations 124, 126 themselves have an annular configuration too, and the first sealing formation 124 isolates the first gas storage volume 114 from the first and second vent ports 116, 118 while the actuator valve 112 is in its closed position, e.g. as shown in Figure 8.

[0152] Additionally, the first and second vent ports 116, 118 are, in turn, arranged in fluid communication with a collapsible chamber 128 which, in the embodiment shown takes the form of a tubular bellow 130, although other forms are possible. The collapsible chamber 128, i.e. tubular bellow 130, is sealingly fixed between the first needle assembly 28 and the shield assembly 42, and more particularly is sealingly fixed, i.e. secured in an essentially permanent, gas-tight, manner, between the needle assembly body 30 and the seal support body 52 of the seal formation 46 of the shield assembly 42, as shown in Figures 19(a) and 19(b). Other embodiments of the invention may, however, have different sealingly fixed configurations of collapsible chamber between the needle and shield assemblies.

[0153] The collapsible nature of the chamber 128, i.e. tubular bellow 130, means that it is moveable between various expanded configurations, e.g. as shown in Figure 19(a) and also in each of Figures 1(b), 13(b), 15(b), 16(b) and 18(b), and various contracted configurations in which it has been collapsed to a differing degree, such as is shown in Figure 19(b) and in each of Figures 14(b), 14(e), 17(b) and 17(e).

[0154] Arrangement of the collapsible chamber 128, i.e. tubular bellow 130, in fluid communication with each of the first and second vent ports 116, 118 means that when the first actuator valve 112, i.e. the first valve member 120, moves into its open position the first gas storage volume 114 comes into fluid communication with collapsible chamber 128 whereby gas (not shown) is released from the first gas storage volume 114 into the collapsible chamber 128, i.e. the tubular bellow 130, via the first and second vent ports 116, 118.

[0155] Such release of gas from the first gas storage volume 114 causes expansion of the collapsible chamber 130, i.e. the tubular bellow 130, in an axial direction, and more particularly in a distal axial direction AD relative to the syringe 12. This pushes the seal support body 52 in the same distal axial direction AD and, by virtue of the seal support body 52 being fixedly secured to the shield body 44, urges the shield assembly 42 from the third secondary position 250 towards the fourth secondary position 260, and more particularly drives the shield assembly 42 into the fourth secondary position 260, whereby the device 10 is rendered into its locked state, e.g. as shown in Figures 18(a) to 18(c).

[0156] In addition to the foregoing, the first actuator module 110 also includes an elongate actuator member 132 that is slidably received within the needle assembly body 30 and fixedly secured to the first actuator valve 112, i.e. the first valve member 120 in the embodiment shown, so that it is able to move the first actuator valve 112, i.e. first valve member 120, from its closed position to its open position, i.e. so as to selectively cause a release of the gas from the first gas storage volume 114. More particularly, in the embodiment shown the actuator member 132 takes the form of hollow actuator tube 134 that is sized to slide over the needle 32 which, as described above, is fixedly secured to the needle assembly body 30. The hollow actuator tube 134 may be welded, adhered or otherwise immovably fixed to the first valve member 120. It is also preferably moveably sealed, e.g. by a first ancillary sealing formation 136, relative to the needle assembly body 30. Other forms of actuator member are also possible, however, as are different fixing and sealing arrangements.

[0157] In the aforementioned manner, sliding of the actuator tube 134 over the needle 30 allows for movement of the actuator tube 134, i.e. actuator member 132, within the needle assembly body 30, while securing of the actuator tube 134, i.e. actuator member 132, to the first valve member 120 means that such relative movement of the actuator tube 134 causes the first valve member 120 to also move within the needle assembly body 30.

[0158] Additionally, a proximal end 138 of the actuator tube 134 defines a first abutment formation 140 against which the syringe plunger 16, and more particularly the piston end 20 of the plunger 16, is able to abut.

[0159] The provision of such a first abutment formation 140 means that in the latter stages of insertion of the plunger 16 within the hollow syringe body 14, e.g. as shown in Figure 17(e), continued insertion of the plunger 16 drives the actuator member 132, i.e. the actuator tube 134, in an axial direction, and more particularly in a distal axial direction AD.

[0160] Such distal axial movement of the actuator tube 134 causes movement of the first actuator valve 112, i.e. the valve member 120, from its closed position towards its open position, e.g. as shown in Figure 18(b), which, in turn, releases gas from the first gas storage volume 114 and thereby causes automatic urging of the shield assembly 42 from the third secondary position 250 towards, and ultimately into, the fourth secondary position 260.

[0161] As described above, the needle assembly body 30 is moveably coupled with the syringe body 14 and, more particularly, helically coupled with the syringe body 14.

[0162] In addition to the foregoing, the needle assembly body 30 is constrained to be rotated by the shield body 44. In the embodiment shown this is achieved by providing the needle assembly body 30 with a pair of opposed wing formations 142 (e.g. as shown in Figures 7, 19(a) and 19(b), each of which cooperates with, and is slidable within, a corresponding guide channel 58 in the shield body 44, as shown in Figure 20.

[0163] Such a combination of helical coupling between the needle assembly body 30 and the syringe body 14, and the needle assembly body 30 being forced to rotate with the shield body 44 (via cooperation of the respective wing formations 142 on the needle assembly body 30 with the corresponding guide channels 58 in the shield body 44), means that rotational movement of the shield body 44 relative to the syringe body 14, and in particular rotational movement in the permitted clockwise circumferential direction Ccw, results in linear movement of the needle assembly body 30 relative to the syringe body 14 and, more particularly results in linear movement in a proximal axial direction Ap.

[0164] It follows that the aforementioned combination permits the harnessing of rotational movement of the shield assembly 42 relative to the syringe 12 and the resulting linear movement of the needle assembly body 30 towards the syringe body 14, i.e. selective movement of the needle assembly body 30 relative to the syringe body 14, to move the abutment formation 140 of the actuator member 132, i.e. of the actuator tube 134, from a shrouded position within the syringe body 14, e.g. as shown in Figure 13(b), into an exposed position in the medicament chamber 18 of the syringe body 14, e.g. as shown in Figure 16(b).

[0165] More particularly, in the embodiment shown movement of the shield assembly 42 from the second secondary position 240 to the second primary position 210 moves the needle assembly body 30 in the proximal axial direction Ap towards the syringe body 14 by a first amount, and hence moves the actuator member abutment formation 140 into the medicament chamber 18 by a corresponding first amount, e.g. as shown in the transition between Figures 13(b) and 15(b), and movement of the shield assembly 42 from the second primary position 210 to the third primary position 220 moves the needle assembly body 30 in the proximal axial direction Ap towards the syringe body 14 by a second amount that is essentially equal to the first amount (by virtue of the first and second angles a, also being equal), and hence moves the abutment formation 140 into the medicament chamber 18 by a further corresponding second amount, e.g. as shown in the transition between Figures 15(b) and 16(b).

[0166] In other embodiments of the invention (not shown) movement of the abutment formation 140 into the medicament chamber 18 to a desired extent may be achieved by a different degree of relative rotational movement rotational movement between the shield assembly 42 and the syringe 12, or indeed by only a single one of the aforementioned moves from the second secondary position 240 to the second primary position 210, and from the second primary position 210 to the third primary position 220, e.g. as may be occasioned by altering the nature of the coupling between the needle assembly body 30 and the syringe body 14.

[0167] Further, in the embodiment shown, such movement of the abutment formation 140 into the medicament chamber 18 is facilitated by the sliding movement of the actuator member 132 relative to the needle assembly body 30 having a greater degree of frictional resistance, e.g. as is provided by frictional engagement of the valve member 12, and more particularly the first and second sealing formations 124, 126 thereof, with the hollow interior 122 of the needle assembly body 30, than the frictional resistance arising between the actuator member 132 and the syringe body 14, e.g. as is provided by much lighter frictional engagement between a second ancillary sealing formation 144 and the actuator member 132.

[0168] In addition to the foregoing, the pair of opposed wing formations 142 of the needle assembly body 30 are arranged in a coplanar manner, i.e. within the same bevelled opening plane PBO, with a bevelled opening 148 in the needle 32, i.e. the chisel tip of the needle 32, e.g. as best shown in Figure 7.

[0169] As a consequence, the aforementioned forced rotation of the needle assembly body 30 by the shield body 44, i.e. via cooperation of the respective wing formations 142 on the needle assembly body 30 with the corresponding guide channels 58 in the shield body 44, additionally means that means that rotational movement of the shield body 44 relative to the syringe body 14, and in particular rotational movement in the permitted clockwise circumferential direction Ccw, results also in rotational movement of the bevelled opening plane PBO, and hence the bevelled opening 148 itself, in the same said clockwise circumferential direction Ccw relative to the syringe body 14.

[0170] In this manner, planar orientation of the bevelled opening 148, i.e. of the bevelled opening plane PBO, relative to the syringe body 14, and more particularly relative to a natural use axis ANU of the flange 24 defined by the syringe body 14 (which essentially bisects the flange 24, as best shown in Figure 4) is constrained in a desired manner.

[0171] More particularly still, rotational movement in the clockwise circumferential direction

[0172] Ccw of the shield assembly 42 from the second secondary position 240 to the second primary position 210, e.g. as shown in the transition between Figures 13(c) and 15(c), and then from the second primary position 210 to the third primary position 220, e.g. as shown in the transition between Figures 15(c) and 16(c), moves the bevelled opening plane PBO into alignment with the natural use axis ANU of the flange 24, i.e. as shown in Figure 16(c).

[0173] Such alignment of the bevelled opening plane PBO with the natural use axis ANU of the flange 24 is beneficial because it ensures the bevelled opening 148, i.e. chisel tip, is optimally orientated relative to the flange 24, so as to help a user correctly insert the needle 32 into a recipient as the device 10 moves between its administration and inserted states, i.e. ensures the bevelled opening 148 is optimally orientated relative to the flange 24 when the device 10 is in each of its administration state (as shown in Figure 16(c)) and its inserted state (as shown in Figure 17(c)).

[0174] Additionally, such alignment provides the option of predetermining the orientation of graduation markings (not shown) on the syringe body 14, e.g. as may be created by an overprint, so as to ensure that the graduation markings are presented, e.g. upwards in use, for easy reading by a medical operative or other healthcare professional, e.g. when giving a subcutaneous injection.

[0175] In use the device 10 is configured to operate in the following sequence.

[0176] With reference to Figures 1(a) to 1(d) in particular, following manufacture and assembly of the device 10 it is arranged with the shield assembly 42 in the first secondary position 230 relative to the syringe 12, such that it adopts the desired shipping state, i.e. with the needle 32 safely enveloped by the shield assembly 42.

[0177] Optionally the plunger 16 is inserted completely within the syringe body 14, e.g. so as to reduce the risk of becoming damaged during shipping of the device 10 to a user. However, as shown in Figure 1(c), the needle assembly body 30 is spaced distally from the syringe body 14 to a pre-set greatest extent, such that the abutment formation 140 of the actuator member 132 lies in its a shrouded position within the syringe body 14. The plunger 16 therefore cannot act upon the abutment formation 140, and inadvertent, unwanted activation of the actuator module 110 (and subsequent automatic release of gas from the gas storage volume 114) is prevented at this stage in the operating sequence of the device 10. Following shipping of the device 10, and when use of the device 10 to administer a medicament is desired, the shield assembly 42 may be moved into the first primary position 200 relative to the syringe 12, as shown in Figures 14(a) to 14(e), e.g. by sliding the pawl member 70 from the first end 76 of the first axially extending slot 74 to the second end 78 thereof.

[0178] Such sliding of the pawl member 70 within the first axially extending slot 74 takes place while the shield assembly 42, and more particularly the seal formation 46 and associated seal member 50 thereof, is held (as shown schematically) in contact with the vial 94, and more specifically the septum (not shown) of such a vial, or vials, from which the or each medicament 92 is to be drawn. The needle 32 is therefore never exposed to the outside environment, and the device 10 is able to adopt the compounding state shown without external contaminants entering the mechanically closed system of the device 10.

[0179] In such a compounding state the plunger 16 is withdrawn within the syringe body 14 so as to draw a desired amount of medicament into the medicament chamber 18, i.e. as shown in the corresponding transition from Figures 14(a) and 14(b) to Figures 14(d) and 14(e).

[0180] Once the aforementioned medicament draw is completed, the shield assembly 42 is moved into the second secondary position 240 relative to the syringe 12, as shown in Figures 13(a) to 13(c), e.g. by sliding the pawl member 70 back from the second end 78 of the first axially extending slot 74 to the first end 76 thereof.

[0181] Such sliding of the pawl member 70 within the first axially extending slot 74 again takes place while the shield assembly 42, and more particularly the seal formation 46 and associated seal member 50 thereof, is held in contact with the vial 94 such that during extension of the shield assembly 42 over the needle 32 as the needle 32 is withdrawn from the vial 94, exposure of the needle 32 to the outside environment is similarly avoided.

[0182] The device 10 thereby adopts its ready state in which the shield assembly 42 envelops the needle 32 and is "ready" to be moved into its second primary position 210 relative to the syringe 12, to thereby adopt its transport state, as shown in Figures 15(a) to 15(c). Such movement into the second primary position 210 is achieved by sliding the pawl member 70 from the first end 82 of the circumferentially extending slot 80, over the first unidirectional mutually cooperable formation 102, i.e. over the first ratchet tooth 106, and into a detent 146 formed between the first and second ratchet teeth 106, 108, e.g. as shown most clearly in Figure 15(c).

[0183] The shape of the first ratchet tooth 106 prevents the pawl member 70 from moving back along the circumferentially extending slot 80, and thus the shield assembly 42 in a counter-clockwise circumferential direction Cccw, which thereby prevents a user from incorrectly moving from the second primary position 210 back to the first primary position 200.

[0184] Meanwhile, location of the pawl member 70 in the circumferentially extending slot 80 prevents linear movement of the shield assembly 42 in each of the proximal and distal axial directions Ap, AD relative to the syringe 12, and so inadvertent retraction of the shield assembly 42 from enveloping the needle 32 is similarly prevented.

[0185] Such temporary "locking" of the shield assembly 42 axially relative to the syringe 12 beneficially means that while in its transport state the device 10 is ideally suited to being moved, e.g. from a medicament compounding area to a recipient administration area, such as a bedside or other healthcare setting.

[0186] It is noted also that movement of the shield assembly 42 into the second primary position 210 additionally moves the abutment formation 140 of the actuator member 132 into the medicament chamber 18 of the syringe body 14 by the pre-set first amount, as best shown in Figure 15(b).

[0187] Following transportation of the device 10, e.g. to the aforementioned recipient administration area, the shield assembly 42 is moved into its third primary position 220 relative to the syringe 12, as shown in Figures 16(a) to 16(c), e.g. by sliding the pawl member 70 from the detent 146 in the circumferentially extending slot 80, over the second unidirectional mutually cooperable formation 104, i.e. over the second ratchet tooth 108, to the second end 84 of the circumferentially extending slot 80, e.g. as shown most clearly in Figure 16(c). The device 10 is thereby in its administration state.

[0188] The shape of the second ratchet tooth 108 similarly prevents the pawl member 70 from moving back along the circumferentially extending slot 80, and thus the shield assembly 42 in a counter-clockwise circumferential direction Cccw, which thereby prevents a user from incorrectly moving from the third primary position 220 back to the second primary position 210.

[0189] Also, movement of the shield assembly 42 into the third primary position 220 additionally moves the abutment formation 140 of the actuator member 132 further into the medicament chamber 18 of the syringe body 14 by the pre-set second amount, as best shown in Figure 16(b). Additionally, such movement completes alignment of the bevelled opening plane PBO with the natural use axis ANU of the flange 24 defined by the syringe body 14, as shown in Figure 16(c), such that the bevelled opening 148 of the needle 32 (not shown in Figure 16(c)) is optimally orientated relative to the flange 24.

[0190] Administration of the medicament may then be started by moving the shield assembly 42 into the third secondary position 250 relative to the syringe 12, as shown in Figures 17(a) to 17(e). This is done by sliding the pawl member 70 from the second end 84 of the circumferentially extending slot 80 to the first end 88 of the second axially extending slot 86, as shown in in Figure 17(c).

[0191] Such sliding of the pawl member 70 within the second axially extending slot 86 takes place while the shield assembly 42, and more particularly the seal formation 46 and associated seal member 50 thereof, is held in contact with a recipient's body (not shown), e.g. a recipient's skin. As a consequence, it is possible to insert the needle 32 into a recipient, and thereby have the device 10 adopt its inserted state, without the needle 32 ever becoming exposed to the outside environment, and thus there being no opportunity for external contaminants to enter the mechanically closed system of the device 10.

[0192] In such an inserted state the plunger 16 may be inserted further into the syringe body 14 so as to inject a desired amount of medicament into a recipient, i.e. as shown in the corresponding transition of the plunger 16 from Figures 17(a) and 17(b) to Figures 17(d) and 17(e).

[0193] As the plunger 16 approaches its furthest insertion into the syringe body 14, as shown in Figures 17(d) and 17(e), it comes into abutting engagement with the abutment formation 140 of the actuator member 132, and continued insertion of the plunger 16 drives the actuator member in the distal axial direction AD, and thereby moves the actuator valve 112, i.e. the valve member 120, towards and into its open position, e.g. as shown in Figure 18(b).

[0194] As described above, movement of the valve member 120 into its open position releases gas from the gas storage volume 114 of the actuator module 110 and causes automatic urging of the shield assembly 42 from the third secondary position 250 towards the fourth secondary position 260.

[0195] Such urging of the shield assembly 42 permits the shield assembly 42, and more particularly the seal formation 46 and associated seal member 50 thereof, to be gently maintained in contact with a recipient's body while the needle 32 is withdrawn from the recipient's body. Consequently it is possible to carry out such withdrawal of the needle 32 without the needle 32 ever becoming exposed to the outside environment, and thus there being no opportunity for external contaminants to enter the mechanically closed system of the device 10, or for there to be any the escape of recipient blood, medicament, or vapour concentrations outside the device 10.

[0196] Following complete withdrawal of the needle, e.g. from a recipient's body, the continued urging of the shield assembly 14 provided by the release of gas into the collapsible chamber 128, i.e. into the tubular bellows 130, drives the pawl member 70 further along the second axially extending slot 86 from the first end 88 thereof completely to the second end 90 thereof, and thus moves the shield assembly 42 into its fourth and final secondary position 260, as shown in Figures 18(a) and 18(b).

[0197] During such movement of the shield assembly 42 into the fourth and final secondary position 260, the latch member 96 is urged into abutment with the tip 98 of the needle 32 and, as described hereinabove, the shield assembly 42 is rendered completely immovable relative to the syringe 12.

[0198] The device 10 thereby adopts its final, locked state in which the needle 32 cannot be exposed and the device 10 cannot be re-used, without being irreparably damaged.

[0199] Figure 21 shows an exploded, isometric view of parts of a second needle assembly 300 which may, as an alternative, be included instead of the first needle assembly 28 in the first device 10 described hereinabove, so as to form a CSTD (not completely shown) according to a second embodiment of the invention. Like features of the second embodiment device, where shown, are designated using the same reference numerals as those in the first device 10. The second needle assembly 300 includes a second actuator module 302 which is similarly configured to selectively urge a corresponding shield assembly relative to a corresponding syringe (not shown) from a corresponding third secondary position, that correlates to an inserted state of the second device, towards a corresponding fourth secondary position which correlates to a locked state of the second device.

[0200] More particularly, the second actuator module 302 includes a second actuator valve 304 that is moveable between a closed position, e.g. as shown in Figures 22(a) and 23(a), in which a gas (not shown) is held under pressure in a second gas storage volume 306, and an open position, e.g. as shown in Figures 22(b) and 23(b), in which the second gas storage volume 306 is arranged in fluid communication with a vent conduit 308 to release the gas from the second gas storage volume 306 and into an interior of a corresponding collapsible container 128 which is coupled to the corresponding shield assembly.

[0201] The vent conduit 308 is, as shown, defined by a hollow conduit member 310 that is fixedly secured, e.g. by welding or other securing arrangement, in a corresponding distal portion 34 of a corresponding needle assembly body 30 of the second needle assembly 300. More particularly, the vent conduit 308 extends between the hollow conduit member 310 and a corresponding hypodermic needle 32 that lies within the conduit member 310 and is similarly fixedly secured at the distal portion 34 of the needle assembly body 30.

[0202] Additionally, the hollow conduit member 310 has an opening 312 formed therein to define an inlet aperture 314 to the vent conduit 308.

[0203] The needle assembly body 30 of the second needle assembly 300 preferably is again coupled, and more particularly moveably coupled, and more particularly still, helically coupled, with a corresponding syringe body of the second CSTD device.

[0204] Such coupling of the needle assembly body 30 with the syringe body similarly retains an interior conduit 40 of the needle 32 in fluid communication with a corresponding medicament chamber within the syringe body.

[0205] Meanwhile, the second actuator valve 304 is different to the first actuator valve 112 described hereinabove in connection with the first device 10, in that while the second actuator valve 304 takes the form of a second valve member 316 that is moveably received within the needle assembly body 30, i.e. within the hollow interior 122 thereof, it is the second valve member 316 itself that defines the second gas storage volume 308.

[0206] More particularly, the second valve member 316 includes an exterior support formation 318 which has a hollow interior 320 that defines the second gas storage volume 306.

[0207] As best shown in Figures 22(a) and 22(b), the exterior support formation 318 is formed from an elongate, hollow, central body 322, preferably of circular cross-section (although other cross-sectional profiles are also possible), to which are secured first and second end caps 324, 326. Preferably the second end cap 326 is integrally formed with the central body 322, and the first end cap 324 is bonded to the central body 322 using a UV-cure adhesive (not shown), although other ways of securing are also possible.

[0208] In other embodiments of the invention (not shown) the first and second end caps may instead extend towards one another and be secured to one another so as to remove the need for the central body.

[0209] In any event, the first end cap 324 incorporates a third sealing formation 328 and the second end cap 326 incorporates a fourth sealing formation 330, both of which sealingly cooperate with the first vent conduit 308, i.e. with the conduit member 310 defining the first vent conduit 308, to maintain the sealing integrity of the second gas storage volume 306.

[0210] The exterior support formation 318 and the first and second end caps 324, 326 of the second valve member 316 thereby combine to create a substantially annular second gas storage volume 306, although other shapes of second gas storage volume are also possible.

[0211] Preferably each of the third and fourth sealing formations 328, 330 is formed from (or includes an element (e.g. an O-ring or skin) formed from) a relatively soft, resiliently deformable material (such as a natural or synthetic elastomer), while the exterior support formation 318, e.g. the central body 322 and each end cap 324, 326, is formed from or includes a harder, less deformable material. For example, one or both of the third and fourth sealing formations 328, 330 may be overmoulded in a thermoplastic elastomer, i.e. created as an additional layer of thermoplastic elastomer material, on the corresponding end cap 324, 326. Additionally, the third and fourth sealing formations 324, 326 are moveable, and more particularly slidable, relative to the vent conduit 308 (while maintaining sealing integrity), such that the second valve member 316 is moveable within the needle assembly body 30, and more particularly is able to run in slight clearance within the hollow, substantially annular interior 122 of the needle assembly body 30, although similarly this need not necessarily be the case and other shapes of interior, as well as only partially hollow interiors are also possible.

[0212] In this manner the second valve member 316 is moveable between a closed position, as shown in Figures 22(a) and 23(a), in which a gas (or other propellant - not shown) is held under pressure in the second gas storage volume 306, and an open position, as shown in Figures 22(b) and 23(b), in which the gas is released from the second gas storage volume 306 to cause shrouding, i.e. complete enveloping or encasing, of the needle 30 by the shield assembly.

[0213] To facilitate such movement of the second valve member 316 similarly defines a second abutment formation 332 against which a corresponding syringe plunger 16 is, in use, able to abut in order to move the second valve member 316 from its closed position towards its open position.

[0214] Prior to use of the second device to inject medicament into a recipient, the second valve member 316 lies in its closed position, as shown in Figures 22(a) and 23(a), and the gas (not shown) remains held under pressure in the second gas storage volume 306.

[0215] During the dispensing of medicament from the second device, the device's plunger 16 is brought into abutment with the second abutment formation 332 of the second valve member 316, such that continued further movement of the plunger 16 in the distal axial direction AD additionally begins to move the second valve member 316 relative to the needle assembly body 30 and towards its open position.

[0216] Such initial movement of the second valve member 316 towards its open position causes movement of the second valve member 316 relative to the conduit member 310, and more particularly causes the second valve member 316 to slide over the conduit member 310. Further movement of the plunger in the distal axial direction AD thereafter moves the second valve member 316 into its open position, as shown in Figures 22(b) and 23(b). This arranges the second gas storage volume 306 in fluid communication with the vent conduit 308, i.e. via the inlet aperture 314 formed in the conduit member 310, such that the gas (not shown) is released from the second gas storage volume 306 and is directed to flow into the vent conduit 308 in the distal axial direction AD, e.g. so as to act upon the collapsible container 128 to cause expansion of the container 128, and thereby cause automatic urging of the shield assembly from the corresponding third secondary position towards, and ultimately into, the corresponding fourth secondary position in which the needle 30 is shrouded by the shield assembly.

Claims

CLAIMS:

1. A closed system transfer device comprising: a syringe having an elongate hollow syringe body within which a plunger is slidably received to define a medicament chamber of varying size depending upon the degree of insertion of the plunger within the syringe body; a needle assembly having a needle assembly body to which a hypodermic needle is fixedly secured, the needle assembly body being coupled with the syringe body to retain an interior conduit of the hypodermic needle in fluid communication with the medicament chamber; and a shield assembly having a shield body moveably coupled with the syringe body, whereby the shield assembly is selectively operable to envelop the needle, the shield body and syringe body including mutually cooperable formations to constrain movement of the shield assembly relative to the syringe through a series of positions corresponding to different operational states of the device.

2. A closed system transfer device according to Claim 1 wherein the shield body is moveably coupled with the syringe body for linear movement in an axial direction along the length of the syringe body and rotational movement in a circumferential direction around an exterior of the syringe body.

3. A closed system transfer device according to Claim 1 or Claim 2 wherein the series of positions includes two or more of: a first primary position corresponding to a compounding state of the device in which one or more medicaments can be drawn from a vial into the medicament chamber; a second primary position corresponding to a transport state of the device in which the shield assembly envelops the needle and movement of the shield assembly relative to the syringe is inhibited to prevent exposure of the needle beyond the shield assembly; and a third primary position corresponding to an administration state of the device in which the needle can be inserted into a recipient and some or all of the contents of the medicament chamber injected into the recipient.

4. A closed system transfer device according to Claim 3 wherein the position of the shield assembly relative to the syringe is selectively restricted to a single one of the first, second or third primary positions.

5. A closed system transfer device according to Claim 3 wherein the mutually cooperable formations of the shield body and syringe body are further configured to allow movement between the primary series of positions in only a single sequence.

6. A closed system transfer device according to Claim 5 wherein the single sequence comprises the first primary position followed by the third primary position.

7. A closed system transfer device according to Claim 6 wherein the single sequence comprises the first primary position followed by the second primary position followed by the third primary position.

8. A closed system drug-transfer device according to any of Claims 5 to 7 wherein at least two primary positions are interposed by at least one unidirectional mutually cooperable formation.

9. A closed system transfer device according to any of Claims 3 to 8 wherein the series of positions further includes one or more of: a first secondary position corresponding to a shipping state of the device in which the shield assembly envelops the needle but is moveable towards the first primary position; a second secondary position corresponding to a ready state of the device in which the medicament chamber contains one or more medicaments while the shield assembly envelops the needle but is moveable towards the second primary position; a third secondary position corresponding to an inserted state of the device in which the needle is able to lie within a recipient; and a fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe.

10. A closed system transfer device according to Claim 9 in which the series of positions includes the fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe, wherein the shield assembly additionally includes a resiliently biased latch member which is urged into abutment with a tip of the needle when the shield assembly moves into the fourth secondary position relative to the syringe, whereby the mutually cooperable formations of the shield body and syringe body further cooperate with the latch member to inhibit linear movement of the shield assembly relative to the syringe.

11. A closed system transfer device according to any preceding claim wherein the mutually cooperable formations of the shield body and syringe body are or include a male formation and a female formation.

12. A closed system transfer device according to Claim 11 wherein the male formation is or includes a resiliently biased pawl member and the female formation is or includes a plurality of slots into which the pawl member is biased.

13. A closed system transfer device according to Claim 12 wherein the female formation includes a first axially extending slot, a circumferentially extending slot extending from one end of the first axially extending slot, and a second axially extending slot intersected by an end of the circumferentially extending slot opposite the end coincident with the first axially extending slot.

14. A closed system transfer device according to Claim 13 wherein one or more of: a first end of the first axially extending slot, being the end from which the circumferentially extending slot extends, defines both the first and second secondary positions; a second end of the first axially extending slot, opposite the first end, defines the first primary position; the second primary position lies along the circumferentially extending slot; a second end of circumferentially extending slot, being the end intersecting the second axially extending slot, defines the third primary position; a first end of the second axially extending slot, being the end nearest to an open end of syringe body, defines the third secondary position; and a second end of the second axially extending slot, being opposite the first end, defines the fourth secondary position.

15. A closed system transfer device according to Claim 9 or any claim depending therefrom wherein the needle assembly includes an actuator module configured to selectively urge the shield assembly relative to the syringe from the third secondary position corresponding to an inserted state of the device in which the needle is able to lie within a recipient towards the fourth secondary position corresponding to a locked state of the device in which the shield assembly envelops the needle and is immoveable relative to the syringe.

16. A closed system transfer device according to Claim 15 wherein the actuator module includes an actuator valve moveable between a closed position in which a gasis held under pressure in a gas storage volume and an open position in which the gas is released from the gas storage volume to cause urging of the shield assembly from the third secondary position towards the fourth secondary position.

17. A closed system transfer device according to Claim 16 wherein movement of the actuator valve into the open position arranges the gas storage volume in fluid communication with a vent port to release the gas from the gas storage volume, the vent port in turn being arranged in fluid communication with a collapsible chamber sealingly fixed between the needle assembly and the shield assembly, whereby release of gas from the gas storage volume via the vent port into the collapsible chamber causes expansion of the chamber in an axial direction which thereby urges the shield assembly from the third secondary position towards the fourth secondary position.

18. A closed system transfer device according to Claim 16 or Claim 17 wherein the actuator valve is or includes a valve member slidably received within the needle assembly body and formed to define the gas storage volume.

19. A closed system transfer device according to Claim 18 wherein the valve member itself defines the gas storage volume.

20. A closed system transfer device according to Claim 19 wherein the valve member includes an exterior support formation having a hollow interior defining the gas storage volume.21 A closed system transfer device according to Claim 18 wherein the valve member cooperates with the needle assembly body to define the gas storage volume therebetween.

22. A closed system transfer device according to Claim 21 wherein the valve member includes first and second axially spaced sealing formations between which is formed an annular gas storage volume.

23. A closed system transfer device according to any of Claims 16 to 22 wherein the actuator module additionally includes an elongate actuator member slidably received within the needle assembly body and fixedly secured to the actuator valve to move the actuator valve from its closed position to its open position, an end of the actuator member defining an abutment formation against which the syringe plunger is able to abut, whereby in the latter stages of insertion of the plunger within the hollowsyringe body continued insertion of the plunger drives the actuator member in an axial direction and thereby causes movement of the actuator valve from its closed position towards its open position which, in turn, causes urging of the shield assembly from the third secondary position towards the fourth secondary position.

24. A closed system transfer device according to Claim 23 wherein the needle assembly body is moveably coupled with the syringe body and selective movement of the needle assembly body relative to the syringe body moves the actuator member abutment formation into the medicament chamber of the syringe body.

25. A closed system transfer device according to Claim 24 wherein the said selective movement of the needle assembly body relative to the syringe body additionally moves one or both of: (i) a bevelled opening plane lying coplanar with a bevelled opening of the hypodermic needle; and (ii) graduation markings, into alignment with a natural use axis of a flange defined by the syringe body.

26. A closed system transfer device according to Claim 24 or Claim 25 wherein the needle assembly body is helically coupled with the syringe body and constrained to be rotated by the shield body, whereby movement of the shield assembly from at least one of the second secondary position to the second primary position and the second primary position to the third primary position achieves one or more of movement of the actuator member abutment formation into the medicament chamber and movement of the bevelled opening plane and / or the graduation markings into alignment with the natural use axis of the flange.

27. A method of using a closed system transfer device according to any preceding claim comprising the step of moving the shield body relative to the syringe body between at least one position corresponding to an operational state of the device and another position corresponding to a different operation state of the device.

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