WO2012063065A1

WO2012063065A1 - Apparatus and method for attaching a needle to a syringe

Info

Publication number: WO2012063065A1
Application number: PCT/GB2011/052180
Authority: WO
Inventors: Ian Charles Cleathero
Original assignee: The Medical House Limited
Priority date: 2010-11-09
Filing date: 2011-11-09
Publication date: 2012-05-18
Also published as: GB2487178A; GB201018923D0

Abstract

An apparatus for attaching a needle (26) to a syringe (14) disposed in an autoinjector device (10), the apparatus including a needle assembly including a needle connected to a needle hub (28), and a fitting adaptor (22) for releaseably gripping the needle assembly. The apparatus is configured to pass through an open front end of the autoinjector to engage the needle hub with the syringe, and the fitting adaptor is configured to subsequently release the needle assembly leaving the needle assembly engaged with the syringe.

Description

Apparatus and Method for Attaching a Needle to a Syringe

[0001] This invention relates to an apparatus for attaching a syringe needle to a syringe, and more specifically although not exclusively, to an apparatus for attaching a syringe needle to a syringe disposed in an autoinjector device.

BACKGROUND

[0002] Autoinjector devices provide an automated means for performing the operation of at least delivering a dose of medicament to a patient. Many autoinjector devices exist that additionally provide other functions such as automated retraction of the needle after delivery and adjustable dosing. Some autoinjectors are built to accommodate syringes that conform to industry standards so that the device is compatible with existing syringes that do not require modification to operate with the device. An example of an autoinjector device is described in WO-A-2005/070481 (The Medical House pic). The autoinjector described in WO-A-2005/070481 (The Medical House pic) may be used with an "industry- standard" syringe that is provided with a fixed needle mounted thereto. The syringe is installed in the device and the device is actuated to deliver a dose of medicament to the patient.

[0003] Some industry standard syringes, however, are not provided with a needle mounted thereto, and a needle must be attached before a dose of medicament can be delivered. An example of such a type of syringe is a Luer-type syringe which has a tapered front end that receives a needle having a complementary tapered needle hub.

[0004] When considering the use of syringes that are not provided with a needle in autoinjector devices, a needle must be fitted before a dose of medicament can be delivered. This presents at least two problems, namely the difficulty of accessing the syringe when installed in the autoinjector device, and the risk of the user injuring themselves with an exposed needle during installation on the syringe.

[0005] It is an object of at least one embodiment of the present invention to provide an apparatus that overcomes the problems associated with the prior art.

BRIEF SUMMARY OF THE DISCLOSURE

[0006] In accordance with the present invention there is provided an apparatus for attaching a needle to a syringe disposed in an autoinjector device, the apparatus including:

a needle assembly including a needle connected to a needle hub; and a fitting adaptor for releaseably gripping the needle assembly;

wherein the apparatus is configured to pass through an open front end of the autoinjector to engage the needle hub with the syringe, and the fitting adaptor is configured to subsequently release the needle assembly leaving the needle assembly engaged with the syringe.

[0007] Thus, the apparatus may be used to conveniently access the syringe within an autoinjector device and install the needle securely whilst minimising the risk of "needle- stick" injuries to the user.

[0008] In a preferable embodiment, the apparatus further comprises a needle cover for releasably gripping the needle assembly, wherein the needle cover is restrained by the fitting adaptor in an axial direction that is parallel to a longitudinal axis of the fitting adaptor, and the fitting adaptor is capable of releasably gripping the needle assembly via the needle cover. This embodiment is particularly suitable for use with needle assemblies that are provided by their manufacturers inside a needle cover. In a particularly preferable embodiment, the fitting adaptor comprises axial blocking means to axially block and restrain the needle cover relative to the fitting adaptor. Therefore, no additional step is required by the user in order to remove the needle cover since the needle cover remains in place during the installation of the needle assembly on the syringe, and the needle cover is then removed with the fitting adaptor since it is restrained relative thereto.

Preferably, the axial blocking means comprises clips on the fitting adaptor.

[0009] Additionally or alternatively, the needle hub is rotationally restrained relative to the needle cover. The needle hub is preferably rotationally restrained relative to the needle cover by engagement of axial ribs on one of the needle hub and needle cover with complementary grooves on the other of the needle hub and the needle cover. In a further or alternative embodiment, the needle cover is rotationally restrained relative to the fitting adaptor. The needle cover is preferably rotationally restrained relative to the fitting adaptor by engagement of axial ribs on one of the needle cover and the fitting adaptor with complementary grooves on the other of the needle cover and the fitting adaptor.

[0010] In one embodiment, the needle hub preferably has a tapered profile for engaging with a complementary front end of the syringe. Preferably, the needle hub has one or more radially extending lugs on an outer surface for engagement with restraining means of the syringe or syringe holder. Alternatively or additionally, the fitting adaptor preferably comprises axial guide ribs on an external surface for engagement with complementary grooves on the autoinjector device to assist alignment of the fitting adaptor when in the autoinjector device. Guidance of the fitting adaptor within the autoinjector device will minimise the risk of the needle assembly being incorrectly installed on the syringe.

[0011] Preferably, the fitting adaptor is configured to grip the needle assembly by frictional forces, where the needle assembly is releaseable from the fitting adaptor when relative axial forces between the needle assembly and fitting adaptor are sufficient to overcome the frictional forces.

[0012] Alternatively, the fitting adaptor preferably includes engagement means on an external surface that are moveable between a first position and a second position; and once the fitting adaptor is inserted into the autoinjector device beyond a predetermined point, in the first position the engagement means prevent removal of the fitting adaptor, and in the second position the engagement means permit removal of the fitting adaptor. In this embodiment, a deliberate action is required to remove the fitting adaptor, ensuring that it is removed at the appropriate time, when the needle assembly is installed on the syringe. Additionally, this embodiment permits a more secure fitting of the needle assembly on the syringe.

[0013] In a particularly preferable embodiment, the fitting adaptor comprises an outer sleeve and an inner sleeve, where the inner sleeve is rotationally mounted in, but axially restrained relative to, the outer sleeve;

the inner sleeve protrudes from an end of the outer sleeve and the engagement means comprise a plurality of radially flexible hooks that radially extend from the protruding part of the inner sleeve;

the first position comprises a radially outward position of the hooks;

the second position comprises a radially inward position of the hooks; and the hooks are moveable from the first position to the second position by rotation of the outer sleeve relative to the inner sleeve.

[0014] Further preferably, one of the plurality of flexible hooks and the outer sleeve comprises an abutment element and rotation of the outer sleeve relative to the inner sleeve causes interference of the abutment element with part of the other of the plurality of flexible hooks and outer sleeve and causes the hooks to move from the first position to the second position. The abutment element preferably comprises an axial rib on each of the hooks, wherein in the first position each axial rib resides in a first groove on an inner surface of the outer sleeve and rotation of the outer sleeve relative to the inner sleeve causes the axial ribs to ride out of the first grooves into the second position. Preferably, the second position each axial rib resides in a second groove, where each of the second grooves is less deep in a radial direction than each of the first grooves. [0015] In accordance with a second aspect of the present invention, there is provided an autoinjector for receiving a needle attached with the apparatus according to the first aspect of the present invention, the autoinjector comprising:

a housing;

a syringe holder inside the housing; and

a syringe disposed within the syringe holder;

wherein the syringe has a tapered forward end for receiving a needle hub of a needle.

[0016] The improved autoinjector is therefore particularly suited for use with a syringe that is provided without a needle but permits safe and easy installation of a needle.

[0017] In a preferable embodiment, the syringe further comprises engagement means for engaging with one or more radially extending lugs on an outer surface of the needle hub. Further preferably, the engagement means comprises a nut disposed around the tapered forward end of the syringe. The forward end of the syringe is preferably provided with a removable seal so that sterility may be maintained before a needle is installed. Preferably, the autoinjector is provided with a seal removal adaptor that is configured to engage with the seal and remove the seal from the forward end of the syringe to facilitate easy removal of the seal.

[0018] In one preferable embodiment, the autoinjector comprises a collar disposed between the syringe and the syringe holder to maintain the syringe in a coaxial position relative to the syringe holder. Preferably, the collar is a discontinuous ring to facilitate easy installation on the syringe during assembly.

[0019] In a particularly preferable embodiment, the engagement means comprise radially flexible arms at a forward end of the syringe holder and are adapted to support the syringe within the syringe holder when a needle hub is engaged on the tapered forward end of the syringe.

[0020] In accordance with a third aspect of the present invention, there is provided a method of attaching a needle to an autoinjector device, including the steps of:

i) providing an autoinjector device according to the second aspect of the present invention;

ii) providing an apparatus according to the first aspect of the present invention; iii) passing the apparatus through an open front end of the autoinjector and engaging the needle hub with the syringe; and

iv) disengaging the fitting adaptor from the needle hub and removing the fitting adaptor from the autoinjector leaving the needle assembly engaged with the syringe.

[0021] In accordance with a fourth aspect of the present invention, there is provided a sterile pack containing the apparatus according to the first aspect of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Embodiments of the invention are further described hereinafter with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of an autoinjector according to an embodiment of the present invention, with a seal removal adaptor connected;

Figure 2 is a cross-sectional view of the front end of the autoinjector of Figure 1 ;

Figure 3 is a cross-sectional view of the front end of the autoinjector of Figure 1 during the removal of the seal and the seal removal adaptor;

Figure 4 is a perspective view of a fitting adaptor according to an embodiment of the present invention;

Figure 5 is a cross sectional view of the fitting adaptor of Figure 4;

Figures 6 and 7 are cross-sectional views of the fitting adaptor of Figure 4 during insertion into the autoinjector of Figure 1 ;

Figures 8 and 9 are cross sectional views of the autoinjector of Figure 1 following the removal of the fitting adaptor of Figure 4;

Figure 10 is a perspective view of an alternative autoinjector according to an embodiment of the present invention, with a seal removal adaptor connected;

Figures 1 1 and 12 are cross-sectional views of the autoinjector of Figure 10 showing the seal and the seal removal adaptor;

Figure 13 is a cross-sectional view of the autoinjector of Figure 10 showing the syringe therein;

Figure 14 is a perspective view of the syringe with collar, locking nut and seal, where the remaining components of the autoinjector are not shown for clarity; Figure 15 is a cross-sectional view of the front end of the autoinjector of Figure 10 during the removal of the seal and the seal removal adaptor;

Figure 16 is a perspective view of a fitting adaptor according to an alternative embodiment of the present invention;

Figure 17 is a perspective view of a sterile blister pack containing the fitting adaptor of Figure 16;

Figure 18 is a cross-sectional view of the fitting adaptor of Figure 16;

Figures 19 to 25 are cross-sectional views of the fitting adaptor of Figure 16 during insertion into the autoinjector of Figure 10 and installation of the needle assembly;

Figure 26 is a cross-sectional view of the autoinjector of Figure 10 following the removal of the fitting adaptor of Figure 16;

Figure 27 is a perspective view of the autoinjector of Figure 10 following removal of the front cap; and

Figure 28 is a perspective view of the autoinjector of Figure 10 held against an injection site for delivery of a dose of medicament.

DETAILED DESCRIPTION

[0023] Figure 1 shows an autoinjector device 10 having an outer housing 12. Protruding from an open front end 12a of the housing 12, is a seal removal adaptor 20. As shown in Figure 2, the seal removal adaptor 20 is connected to a seal 18 via hooks 20b at a rear end of the seal removal adaptor 20. The seal 18 seals a forward end of a syringe 14 disposed within the autoinjector device 10. The syringe 14 is held within the device 10 by a syringe holder 16 which has a pair of radially flexible arms 16a at a front end. When the seal 18 is in place over the front end of the syringe 14, the flexible arms 16a are flexed radially outwards slightly due to the presence of the seal 18, and are therefore biased radially inwardly against the seal 18 keeping the seal 18 in position at the front end of the syringe. At a forward end of the seal removal adaptor 20 there are a plurality of circumferential ribs 20a to improve grip so that a user can grasp the seal removal adaptor 20 and pull it axially forward to remove the seal 18 from the front end of the syringe 14 and withdraw the seal removal adaptor 20 and the seal 18 from the autoinjector device 10. Once the seal 18 is removed (as shown in Figure 3), the flexible arms 16a flex radially inwards to their relaxed position and the unsealed syringe 14 is ready to receive a needle so that the autoinjector can deliver a dose of medicament. [0024] In the position shown in Figure 3, the syringe 14 is supported in the syringe holder 16 at its rear end (not shown). In particular, a finger flange (not shown) of the syringe 14 is resting on the rear end of the syringe holder 16 which has a smaller radius than the radial extent of the finger flange (which may not be circular). The syringe holder 16 has rear clips that limit (but do not prevent) rearward movement of the syringe 14 relative to the syringe holder 16.

[0025] As shown in Figure 2, the forward end of the syringe 14 has a luer-type tapered profile 14a with a central channel 14b running therethrough from the barrel of the syringe 14. Since the front end of the syringe 14 is axially separated from the front open end 12a of the housing 12 of the device 10, a fitting adaptor 22 is used to attach the needle. The fitting adaptor 22, shown in detail in Figures 4 and 5, is a tubular element with a splined forward end 22a, to improve grip, and a plurality of hooks 22b at a rear end. The hooks 22b axially restrain a needle cover 30 which is disposed within the fitting adaptor 22 by engagement with a flanged rear end 30a of the needle cover 30. Disposed in the needle cover 30 is a needle assembly 24 comprising a needle 26 that is connected to a needle hub 28. The needle assembly 24 is held in the needle cover 30, and hence the fitting adaptor 22, by a friction fit between the needle hub 28 and the needle cover 30. The inside of the needle cover 30 comprises axial ribs or splines that engage with

complementary grooves or splines on the outer surface of the needle hub 28 to prevent relative rotation between the needle hub 28 and the needle cover 30. In alternative embodiments, the needle hub 28 may comprise axial ribs or splines on its outer surface that engage with grooves or splines on the inner surface of the needle cover 30.

[0026] The needle hub 28 has a tapered inner profile 28a for fitting over and engaging with the tapered profile 14a of the forward end of the syringe 14. The needle hub 28 also has a flanged rear end 28b where the flange 28b serves as a lug for engagement with the flexible arms 16a of the syringe holder 16.

[0027] In preferable embodiments, the fitting adaptor 22, needle cover 30 and needle assembly 24 are all provided assembled, as shown in Figures 4 and 5, in a sterile pack, such as a blister pack.

[0028] To fit the needle assembly 24 to the syringe 14, the user passes the assembled fitting adaptor 22, needle cover 30 and needle assembly 24 through the open end 12a of the housing 12 of the autoinjector device 10 towards the front end of the syringe 14 (as shown in Figure 6). As the fitting adaptor passes through the open end 12a of the housing 12 into the device 10, guide ribs 22c on the outer surface of the fitting adaptor 22 guide the adaptor into the autoinjector 10 ensuring an axial and non-rotational movement and maintaining a coaxial position. The guide ribs 22c each have a chamfered rear edge 22d for leading the guide ribs 22c into complementary grooves on an inner surface of the autoinjector 10 to guide the passage of the fitting adaptor 22 therethrough. When the needle hub 28 reaches the forward end of the syringe 14, the lugs (flange) 28b of the needle hub 28 contact a chamfered leading inner surface 16a' of the flexible arms 16a causing the flexible arms 16a to flex radially outwardly. The syringe holder 16 is axially restrained (e.g. by clips (not shown) attached to the finger flange of the syringe 14) so that it does not move axially in response to the flange 28b acting on the flexible arms 16a. The flange 28b of the needle hub 28 continues to move axially rearwardly until it passes the flexible arms 16a allowing them to flex radially inwardly once more to a position that is in axial alignment with and axially forward of the flange 28b. In this position, the flexible arms 16a block the forward axial path of the flange 28b of the needle hub 28. Further rearward axial movement of the fitting adaptor 22, needle cover 30 and needle assembly 24 engages the needle hub 28 with the forward end of the syringe 14. In particular, the engagement arises due to a friction fit between the tapered profile 28a of the inside of the needle hub 28 and the tapered profile 14a of the outer surface of the forward end of the syringe 14, and the flexible arms 16a acting radially inwardly against the needle hub 28 (as shown in Figure 7). Additionally, the tapered inner profile 28a of the needle hub 28 serves to ensure that the needle hub 28 engages centrally on the tapered profile of the syringe 14.

[0029] With the needle assembly 24 engaged on the syringe 14, the fitting adaptor 22 and needle cover 30 may be removed from the device 10. To do this, the user grips the splined forward end 22a (the splines providing extra grip) of the fitting adaptor 22 and pulls the fitting adaptor 22 axially forwardly relative to the autoinjector device 10. Provided the axially forward force applied to the fitting adaptor 22 is greater than the forces retaining the needle hub 28 on the tapered part 14a of the syringe 14, the fitting adaptor 22 and the needle cover 30 (which is axially restrained relative to the fitting adaptor 22 by hooks 22b) can be pulled free of the autoinjector 10 leaving the needle assembly 24 engaged with the syringe 14 (as shown in Figure 8). In this instance, the flexible arms 16a act as restraining means, serving to restrain axial movement of the needle assembly 24 relative to the syringe holder 16 and therefore syringe 14, and retain the needle assembly 24 on the syringe 14. If, for any reason, the needle hub 28 did not properly engage with the syringe 14 (i.e. not be sufficiently restrained by flexible arms 16a), then the needle assembly 24 will be removed from the autoinjector device 10 when the fitting adaptor 22 and needle cover 30 are removed. In this case, the user can repeat the above described steps to correctly install the needle assembly 24 in the autoinjector 10.

[0030] During the installation of the needle assembly 24 on the front end of the syringe 14, the syringe 14 moves axially rearwardly relative to the syringe holder 16. The maximum amount of axial rearward movement of the syringe 14 relative to the syringe holder 16 is determined by the clips at the rear of the syringe holder 16. With the needle assembly 24 in place on the syringe 14, the syringe 14 will be supported in the syringe holder 16 at its forward end by the flexible arms 16a of the syringe holder 16, acting through the needle hub 28 which is securely held on the forward end of the syringe 14. In this position, the syringe 14 will be axially displaced, slightly, relative to the syringe holder 16 such that the finger flange of the syringe 14 is not in contact with rear end of the syringe holder 16. The flexible arms 16a restrain the syringe 14 relative to the syringe holder 16 throughout the entire injection process (e.g. penetration, delivery and retraction).

[0031] With the needle assembly 24 correctly installed on the front end of the syringe 14, the device 10 may be used to deliver a dose of medicament to a patient. To initiate the injection sequence, the user removes a front cap 13 of the housing 12, exposing a front housing 32 of the device 10, places the front end of the device 10 against an injection site and actuates the device 10 (this could be by sliding the housing 12 axially forwards towards the injection site, or pressing a button, for example). Upon actuation, the insertion phase is initiated where the syringe 14 and needle assembly 24 move axially forwardly relative to the autoinjector 10 to expose the needle 26 (as shown in Figure 9) and penetrate an injection site. During the insertion phase, a drive element (not shown) acts on the syringe 14 to push the syringe 14 and needle assembly 24 axially forwards.

During this phase, the syringe 14 is all the while supported by the syringe holder 16 via the flexible arms 16a and the needle hub 28.

[0032] The flexible arms 16a each have chamfered leading outer surface 16a" as shown in Figure 9. These chamfered leading outer surfaces 16a" guide the flexible arms 16a to follow a path radially inwards of a boss 32a formed within the front housing 32 of the device 10 during the insertion phase. In particular, if the flexible arms 16a are not adequately gripping radially inwardly against the needle hub 28 due to them being stored in a radially outward position (with the seal 18 in place) for a long period of time, the chamfered leading outer surfaces 16a" ride against the boss 32a during the insertion phase forcing the flexible arms to flex radially inwardly against the needle hub 18 reducing the risk of any functional problems. Additionally, if the needle hub 28 was not previously fully engaged on the tapered profile 14a of the syringe 14, the loading of the syringe 14 against the flexible arms 16a via the needle hub 18 during the insertion phase ensure that correct engagement is established.

[0033] An autoinjector 1 10 according to a second embodiment of the present invention is shown in Figure 10. The autoinjector 1 10 has a housing 1 12 having a front open end 1 12a and initially includes a seal removal adaptor 120 which is disposed partially within the autoinjector device 1 10 and partially protruding therefrom through the open end 1 12a. The seal removal adaptor 120 has a plurality of circumferential ribs 120a to assist gripping and removal of the seal removal adaptor 120. As seen in Figures 1 1 and 12, the autoinjector 1 10 has a syringe 1 14 disposed therein that is held within a syringe holder 1 16. The syringe 1 14 has a forward end having a luer-type tapered profile 1 14a which is initially sealed with a seal 1 18. The seal 1 18 is connected to the seal removal adaptor 120 by hooks 120b at the rear end of the seal removal adaptor 120.

[0034] As shown in Figure 13, the syringe 1 14 is supported in the syringe holder 1 16 by a collar 1 19 that surrounds the barrel of the syringe 1 14 at a rear end. The collar 1 19 supports the syringe 1 14 in the syringe holder 1 16 and has two tiers 1 19a, 1 19b as shown in Figures 13 and 14. The first tier 1 19a is axially forwards and radially inwards of the second tier 1 19b. The collar 1 19 also has an axial slit 1 19c to enable the collar 1 19 to be snap fitted around the syringe 1 14 during assembly (i.e. the collar 1 19 is a discontinuous ring). When installed, the collar 1 19 surrounds the syringe 1 14 at its rear end, just axially forwards of a finger flange 1 14c of the syringe 1 14. The first tier 1 19a has a thickness such that, when the collar 1 19 is installed on the syringe 1 14, the first tier 1 19c is radially inward of the syringe holder 1 16 and sits inside the syringe holder 1 16, substantially filling the annulus between the syringe 1 14 and the syringe holder 1 16. In contrast, the second tier 1 19b has a thickness such that, when the collar 1 19 is installed on the syringe 1 14, the second tier 1 19b is radially outward of the syringe holder 1 16 and cannot pass into the annulus between the syringe 1 14 and the syringe holder 1 16. Therefore, the second tier 1 19b acts as a step that allows the collar 1 19 to sit at the rear end of the syringe holder 1 16 maintaining the axial position of the syringe 1 14 and ensuring that the syringe 1 14 is central in the syringe holder 1 16. Clips 1 15 protruding from the rear end of the syringe holder 1 16 limit axial movement of the syringe 1 14 relative to the syringe holder 1 16.

[0035] Disposed around the tapered profile 1 14a of the front end of the syringe 1 14 is a locking nut 1 17. The locking nut 1 17 circumferentially surrounds but is radially spaced from the tapered profile 1 14a of the syringe 1 14. When the seal 1 18 is place over the tapered profile 1 14a of the syringe 1 14, the locking nut 1 17 partially surrounds the seal 1 18, as shown in Figures 13 and 14.

[0036] The primary function of the collar 1 19 is to maintain the syringe 1 14 in a coaxial position relative to the syringe holder 1 16. This is particularly important in this

embodiment, since the syringe holder 1 16 is formed such that the syringe 1 14 is not a close fit therein. The reason that the syringe holder 1 16 has a slightly larger diameter in the embodiment described with reference to Figures 10 to 28 compared with the embodiment of Figures 1 to 9 is that it must be large enough to allow the assembly of the syringe 1 14 with the locking nut 1 17 therein, through the rear end of the syringe holder 1 16.

[0037] The seal 1 18 is removed from the syringe 1 14 by axially pulling the seal removal adaptor 120 forwardly through the open end 1 12a of the housing 1 12, as shown in Figure 15. During this process, a cap 1 13 of the housing 1 12 remains in place which prevents the device being actuated until removed. Once the seal 1 18 is removed, the syringe 1 14 is ready to receive a needle so that the device 1 10 can be prepared to deliver a dose of medicament.

[0038] A fitting adaptor 122 (shown in detail in Figures 16 and 18) is used to fit a needle to the syringe 1 14 which is located within the housing 12 of the device 10. As shown in Figure 16, the fitting adaptor 122 comprises an outer sleeve 122a and an inner sleeve 123a disposed within the outer sleeve 122a. The outer sleeve 122a has a splined forward end 122c (to improve grip), and a pair of hooks 122b extending axially rearwardly from a rear end. As shown more clearly in the cross sectional view of Figure 18, the rear hooks 122b axially restrain a needle cover 130 within the fitting adaptor 122. In particular, the needle cover 130 is disposed over a needle assembly 124 that comprises a needle 126 and a needle hub 128 that is held in the needle cover 130 by a friction fit. The needle hub 128 has a tapered luer-type inner profile 128a that is complementary to the tapered profile 1 14a of the syringe 1 14, and a flanged rear end 128b that serves as a lug for establishing a connection with the syringe 1 14. The needle cover 130 has a flanged rear end 130a that is held by the hooks 122b of the outer sleeve 122 to axially restrain the needle cover 130 relative to the fitting adaptor 122. The inner sleeve 123a is disposed within the outer sleeve 122a around the needle cover 130 and comprises a pair of radially flexible legs 123b. At a forward end of the inner sleeve 123a is a discontinuous spigot 123c that abuts against stops 122d formed on the inside of the outer sleeve 122a. The abutment between the stops 122d and the spigot 123c limits axial movement of the inner sleeve 123a relative to the outer sleeve 122a and limits (but does not entirely prevent) relative rotation therebetween.

[0039] In preferable embodiments, the fitting adaptor 122, needle assembly 124 and needle cover 130 are provided pre-assembled in a sterile pack, such as a blister pack. An example of a sterile blister pack 200 containing the pre-assembled fitting adaptor 122, needle assembly 124 and needle cover 130 is shown in Figure 17. The blister pack 200 comprises a body 204 for containing the pre-assembled components and a peelable lid 202 that is capable of being sealed so as to maintain sterility and is capable of being peeled by hand so as to facilitate easy removal of the pre-assembled components. [0040] To install the needle assembly 124 onto the syringe 1 14, the needle assembly 124 with the fitting assembly 122 and needle cover 130 are passed through the open front end 1 12a of the housing 1 12 of the device 1 10 as indicated by the arrow in Figure 19. In preferable embodiments, the fitting assembly 122 is a close fit inside the autoinjector device 1 10 so that it is guided towards the syringe 1 14. Alternatively or additionally, one of the fitting adaptor 122 and the autoinjector 1 10 has axial guiding ribs that cooperate with axial grooves on the other of the fitting adaptor 122 and autoinjector 1 10 to guide the fitting adaptor 122 within the autoinjector 1 10. During the insertion, the flexible legs 123b of the inner sleeve 123a are forced radially inwardly by interference with the inside of a front housing of the autoinjector device 1 10 that is disposed within the cap 1 13 of the housing 1 12. Continued insertion of the fitting assembly 122, needle assembly 124 and needle cover 130 allows the flexible legs 123b to relax and flex radially outwardly once they are axially rearward of a boss 132a of the front housing 132. With the flexible legs 123b flexed radially outwardly axially rearward of the boss 132a of the front housing 132, axial removal of the fitting adaptor 1 12 is prevented. Further rearward axial motion locates the needle hub 128 onto the tapered profile 1 14a of the syringe 1 14. Once located on the syringe 1 14, the needle assembly 124 is held in place by a friction fit between the tapered inner profile 128a of the needle hub 128 and the tapered profile 1 14a of the syringe 1 14, and a friction fit between the lug 128b of the needle hub 128 and the locking nut 1 17. Further views of the needle assembly 124 fully located on the syringe 1 14 are shown in Figures 21 and 22.

[0041] In order to remove the fitting adaptor 122 and the needle cover 130, a release mechanism must be actuated. In particular, the flexible legs 123b must be flexed radially inwardly to pass out of the autoinjector 1 10 through the boss 132a of the front housing 132. As shown in Figure 23, each flexible leg 123b (only one flexible leg 123b is shown) has an axial rib 123c that is initially disposed in a complementary first groove 122e on the inner surface of the outer sleeve 122a. In this position, the flexible legs 123b are flexed radially outwards so that they cannot pass axially through the boss 132a. In order to release the fitting adaptor 122 and needle cover 130 from the autoinjector 1 10, the user must rotate the outer sleeve 122a (indicated by arrow R1 in Figure 20) relative to the inner sleeve 123a. As the torque applied to the outer sleeve 122a increases, the axial ribs 123c on the flexible legs 123b disengage from the first grooves 122e and rotate about 15°. The extent of rotation of the inner sleeve 123a relative to the outer sleeve 122a is limited by the abutment between the stops 122d of the outer sleeve 122a and the spigot 123c of the inner sleeve 123a. Once fully rotated by the amount permitted by the stops 122d, the ribs 123c and flexible legs 123b will be compressed radially inwards by interference with the outer sleeve 122a. In the embodiment shown in the Figures, in this position, the ribs 123c are each disposed in a second groove 122f of the outer sleeve 122a that is shallower than the first grooves 122e in a radial direction. The presence of the second grooves 122f reduces the risk of the inner sleeve 123a rotating back to its initial position relative to the outer sleeve 122a. In alternative embodiments, the second grooves 122f will not be present and the ribs 123c will simply interfere with the inner surface of the outer sleeve 122a causing the flexible legs 123b to flex radially inwardly.

[0042] In the rotated position shown in Figures 24 and 25, the fitting adaptor 122 may be removed from the autoinjector device 1 10 by pulling axially forwardly. Since the flexible legs 123b are flexed radially inwardly, they can pass through the boss 132a of the front housing 132. The boss has a radially inwardly sloping top edge 132b that leads the flexible legs 123b radially inwardly further to facilitate removal. Since hooks 122b of the outer sleeve 122a prevent relative axial movement between the outer sleeve 122a and the needle cover 130, the removal of the fitting adaptor 122 causes removal of the needle cover 130 also, leaving the needle assembly 124 fixed to the syringe (as shown in Figure 26).

[0043] With the needle assembly 124 attached, the autoinjector 1 10 is ready to use by first removing the front cap 1 13 (as shown in Figure 27), placing the front end of the autoinjector 1 10 against the injection site 300 (as shown in Figure 28) and pressing the actuation button 400. In alternative embodiments, the device 1 10 may be actuated by alternative means, other than button 400.

[0044] Throughout the description and claims of this specification, the word "axial" and variations thereof mean parallel to a central longitudinal axis of the autoinjector device. Terms such as "radial" and "circumferential" are relative to the central longitudinal axis. Additionally, terms such as "front", "forward" and "forwardly" are in reference to the end of the autoinjector that the injection is delivered from (i.e. the end closest to the injection site during delivery). Similarly, terms such as "back", "rear" and "rearwardly" are in reference to the end of the autoinjector device that is opposite to the above-defined front end.

[0045] Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to", and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0046] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0047] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

Claims

1. An apparatus for attaching a needle to a syringe disposed in an autoinjector

device, the apparatus including:

a needle assembly including a needle connected to a needle hub; and a fitting adaptor for releaseably gripping the needle assembly; wherein the apparatus is configured to pass through an open front end of the autoinjector to engage the needle hub with the syringe, and the fitting adaptor is configured to subsequently release the needle assembly leaving the needle assembly engaged with the syringe.

2. An apparatus according to claim 1 , further comprising a needle cover for

releasably gripping the needle assembly, wherein the needle cover is restrained by the fitting adaptor in an axial direction that is parallel to a longitudinal axis of the fitting adaptor, and the fitting adaptor is capable of releasably gripping the needle assembly via the needle cover.

3. An apparatus according to claim 2, wherein the fitting adaptor comprises axial blocking means to axially block and restrain the needle cover relative to the fitting adaptor.

4. An apparatus according to claim 3, wherein the axial blocking means comprises clips on the fitting adaptor.

5. An apparatus according to any of claims 2 to 4, wherein the needle hub is

rotationally restrained relative to the needle cover.

6. An apparatus according to claim 5, wherein the needle hub is rotationally

restrained relative to the needle cover by engagement of axial ribs on one of the needle hub and needle cover with complementary grooves on the other of the needle hub and the needle cover.

7. An apparatus according to any of claims 2 to 6, wherein the needle cover is rotationally restrained relative to the fitting adaptor.

8. An apparatus according to claim 7, wherein the needle cover is rotationally

restrained relative to the fitting adaptor by engagement of axial ribs on one of the needle cover and the fitting adaptor with complementary grooves on the other of the needle cover and the fitting adaptor.

9. An apparatus according to any preceding claim, wherein the needle hub has a tapered profile for engaging with a complementary front end of the syringe.

10. An apparatus according to any preceding claim, wherein the needle hub has one or more radially extending lugs on an outer surface for engagement with restraining means of the syringe or syringe holder.

1 1 . An apparatus according to any preceding claim, wherein the fitting adaptor

comprises axial guide ribs on an external surface for engagement with

complementary grooves on the autoinjector device to assist alignment of the fitting adaptor when in the autoinjector device.

12. An apparatus according to any preceding claim, wherein the fitting adaptor is

configured to grip the needle assembly by frictional forces, where the needle assembly is releaseable from the fitting adaptor when relative axial forces between the needle assembly and fitting adaptor are sufficient to overcome the frictional forces.

13. An apparatus according to any of claims 1 to 1 1 , wherein the fitting adaptor

includes engagement means on an external surface that are moveable between a first position and a second position; and once the fitting adaptor is inserted into the autoinjector device beyond a predetermined point, in the first position the engagement means prevent removal of the fitting adaptor, and in the second position the engagement means permit removal of the fitting adaptor.

14. An apparatus according to claim 13, wherein:

the fitting adaptor comprises an outer sleeve and an inner sleeve, where the inner sleeve is rotationally mounted in, but axially restrained relative to, the outer sleeve;

the first position comprises a radially outward position of the hooks;

15. An apparatus according to claim 14, wherein one of the plurality of flexible hooks and the outer sleeve comprises an abutment element and rotation of the outer sleeve relative to the inner sleeve causes interference of the abutment element with part of the other of the plurality of flexible hooks and outer sleeve and causes the hooks to move from the first position to the second position.

16. An apparatus according to claim 15, wherein the abutment element comprises an axial rib on each of the hooks, wherein in the first position each axial rib resides in a first groove on an inner surface of the outer sleeve and rotation of the outer sleeve relative to the inner sleeve causes the axial ribs to ride out of the first grooves into the second position.

17. An apparatus according to claim 16, wherein in the second position each axial rib resides in a second groove, where each of the second grooves is less deep in a radial direction than each of the first grooves.

18. An apparatus for attaching a needle to a syringe disposed in an autoinjector device substantially as hereinbefore described with reference to the accompanying drawings.

19. A sterile pack containing the apparatus of any preceding claim.

20. An autoinjector for receiving a needle attached with the apparatus of any of claims 1 to 18, the autoinjector comprising:

a housing;

a syringe holder inside the housing; and

a syringe disposed within the syringe holder;

21 . An autoinjector according to claim 20, wherein the syringe further comprises

engagement means for engaging with one or more radially extending lugs on an outer surface of the needle hub.

22. An autoinjector according to claim 21 , wherein the engagement means comprises a nut disposed around the tapered forward end of the syringe.

23. An autoinjector according to any of claims 20 to 22, wherein the forward end of the syringe is provided with a removable seal.

24. An autoinjector according to claim 22, provided with a seal removal adaptor that is configured to engage with the seal and remove the seal from the forward end of the syringe.

25. An autoinjector according to any of claims 20 to 24, further comprising a collar disposed between the syringe and the syringe holder to maintain the syringe in coaxial position relative to the syringe holder.

26. An autoinjector according to claim 25, wherein the collar is a discontinuous ring.

27. An autoinjector according to claim 21 , wherein the engagement means comprise radially flexible arms at a forward end of the syringe holder and are adapted to support the syringe within the syringe holder when a needle hub is engaged on the tapered forward end of the syringe.

28. An autoinjector for receiving a needle substantially as hereinbefore described with reference to the accompanying drawings.

29. A method of attaching a needle to an autoinjector device, including the steps of: i) providing an autoinjector device according to any of claims 20 to 28; ii) providing an apparatus according to any of claims 1 to 18;

iii) passing the apparatus through an open front end of the autoinjector and engaging the needle hub with the syringe; and

30. A method of attaching a needle to an autoinjector device substantially as

hereinbefore described with reference to the accompanying drawings.