Adaptor for a Needleless Access Device and Method for Connecting Said Device Thereon

Abstract

An adaptor for connecting a drug delivery device to a needleless access device having a straight external thread, including engagement means for mounting said adaptor on the drug delivery device, and an internal thread intended to cooperate with said external thread on a determined length, said internal thread showing on a distal part of said length a first major diameter mating that of said straight external thread, wherein said internal thread shows on a proximal part of said length a second major diameter, where the second major diameter is strictly smaller than the first major diameter, said internal thread further including a tapered portion linking said proximal part to said distal part.

Claims

1. A needleless access device provided with a straight external thread, the needleless access device comprising: an adaptor for connecting a drug delivery device to the needleless access device, the adaptor comprising: a globally tubular body having a proximal region and a distal region, said proximal region being provided with an engagement element for mounting said adaptor on the drug delivery device, said distal region being provided on its inner wall with an internal thread cooperating with said external thread on a determined length of said internal thread, said internal thread having on a distal part of said length, said distal part having a first length, a first major diameter of constant value mating that of said straight external thread, wherein said internal thread has, on a proximal part of said first length, a second major diameter, where the second major diameter is strictly smaller than the first major diameter, wherein said internal thread further comprises a tapered portion linking said proximal part to said distal part, said tapered portion having a second length.

2. The needleless access device according to claim 1, wherein the ratio of the second major diameter to the first major diameter ranges from 0.95 to 0.98.

3. The needleless access device according to claim 1, wherein said proximal part having a third length, the second major diameter having a constant value over the third length.

4. The needleless access device according to claim 1, wherein the ratio of the first length of the distal part to the second length of the tapered portion ranges from 0.9 to 1.1.

5. The needleless access device according to claim 1, wherein said engagement element comprises a proximal inner rim frictionally engageable on the distal tip of the drug delivery device.

6. The needleless access device according to claim 5, wherein the inner rim is radially expandable.

7. The needleless access device according to claim 1, wherein the ratio of the first length of the distal part to the third length of the proximal part ranges from 1.125 to 1.325.

8. The needleless access device according to claim 1, wherein the ratio of the second length of the tapered portion to the third length of the proximal part ranges from 1.125 to 1.325.

9. The needleless access device according to claim 1, wherein the needleless access device further comprises the drug delivery device comprising a distal tip defining an axial passageway for the transfer of a product contained in said drug delivery device, the adaptor being mounted on said distal tip.

10. The needleless access device according to claim 9, wherein the distal tip is made of glass.

11. The needleless access device according to claim 9, wherein the distal tip is conical and distally tapered.

12. An adaptor for connecting a drug delivery device to a needleless access device provided with a straight external thread, the adaptor comprising: a globally tubular body having a proximal region and a distal region, said proximal region being provided with an engagement element for mounting said adaptor on the drug delivery device, said distal region being provided on its inner wall with an internal thread intended to cooperate with said external thread on a determined length of said internal thread so as to connect said needleless access device to said adaptor, said internal thread having on a distal part of said determined length, said distal part having a first length, a first major diameter of constant value mating that of said straight external thread, wherein said internal thread has on a proximal part of said determined length a second major diameter, where the second major diameter is smaller than the first major diameter, wherein said internal thread further comprises a tapered threaded portion linking said proximal part to said distal part, said tapered threaded portion having a second length, the internal thread being configured to increase the friction between the straight external thread and the tapered threaded portion and the proximal part of this internal thread, the proximal part, the tapered threaded portion and the distal part of the internal thread being configured to cooperate simultaneously with the same straight external thread of the needleless access device.

13. The adaptor according to claim 12, wherein the ratio of the second major diameter to the first major diameter ranges from 0.95 to 0.98.

14. The adaptor according to claim 12, wherein said proximal part having a third length, the second major diameter has a constant value over the third length.

15. The adaptor according to claim 12, wherein the ratio of the first length of the distal part to the second length of the tapered portion ranges from 0.9 to 1.1.

16. The adaptor according to claim 12, wherein said engagement element comprises a proximal inner rim frictionally engageable on the distal tip of the drug delivery device.

17. The adaptor according to claim 16, wherein the inner rim is radially expandable.

18. The adaptor according to claim 12, wherein the ratio of the first length L1 of the distal part to the third length of the proximal part ranges from 1.125 to 1.325.

19. The adaptor according to claim 12, wherein the ratio of the second length of the tapered portion to the third length of the proximal part ranges from 1.125 to 1.325.

20. A drug delivery device comprising a distal tip defining an axial passageway for the transfer of a product contained in said drug delivery device, wherein the drug delivery device further comprises at least one adaptor according to claim 12 mounted on said distal tip.

21. The drug delivery device according to claim 20, wherein the distal tip is made of glass.

22. The drug delivery device according to claim 20, wherein the distal tip is conical and distally tapered.

23. A method for connecting a needleless access device provided with a straight external thread onto an adaptor according to claim 12, comprising at least the step of screwing said straight external thread into the internal thread of the adaptor on said determined length of said internal thread.

24. A method for connecting a drug delivery device to a needleless access device provided with a straight external thread, comprising the following steps: providing an adaptor according to claim 12, engaging said adaptor on the drug delivery device via the engagement element, and screwing said straight external thread into the internal thread of the adaptor on said determined length of said internal thread.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The invention and the advantages arising therefrom will clearly emerge from the detailed description that is given below with reference to the appended drawings in which:

[0044] FIG. 1 is a cross sectional view of an embodiment of the adaptor of the invention,

[0045] FIG. 2 is a partial enlarged view of the adaptor of FIG. 1,

[0046] FIG. 3 is a cross sectional view showing a step of the connection of a needleless access device onto the adaptor of FIG. 1, and

[0047] FIG. 4 is an exploded perspective view of the connection of a needleless access device to a drug delivery device via the adaptor of FIG. 1.

DESCRIPTION OF THE INVENTION

[0048] With reference to FIG. 1, is shown an adaptor 1 of the disclosure, for connecting a drug delivery device, such as the drug delivery device 100 represented on FIG. 4, to a needleless access device, such as the needleless access device 200 shown on FIGS. 3 and 4.

[0049] The adaptor 1 includes a tubular body 2 having a proximal region 2a and a distal region 2b. As will appear from the description below, the adaptor 1 is intended to be connected to the drug delivery device 100 by its proximal region 2a.

[0050] In this view, the proximal region 2a of the tubular body 2 is provided with an inner annular rim 3 defining a central bore 4. The inner annular rim 3 is radially expandable so as to fit with friction on the distal tip 101 of the drug delivery device 100. On the example shown, the inner annular rim 3 is formed of a plurality of circumferentially distributed tabs 3a (see also FIG. 4), separated from each other by a plurality of spaces 3b, providing said inner rim 3 with the capability of being expanded radially. As appears from FIG. 4, the distal tip 101 is conical. The annular rim 3 forms engagement means for engaging the adaptor 1 to the distal tip 101 of the drug delivery device 100, as the inner face of the tabs 3a is intended to be in contact with an outer surface of the distal tip 101 when the adaptor 1 is engaged on the distal tip 101, so that the tabs 3a may act as retaining means of the adaptor 1 onto the distal tip 101. In other embodiments not shown, the inner rim could show alternative designs as long as these designs provide flexibility to said rim.

[0051] The adaptor 1 may be made of any plastic material providing it with the desired flexibility, such as a material selected from acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polyoxymethylene (POM), polystyrene (PS), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), polyamide (PA), thermoplastic elastomer (TPE) and their combinations.

[0052] The adaptor 1 is intended to be connected to the needleless access device 200 via its distal region 2b.

[0053] The distal region 2b of the tubular body 2 is provided on its inner wall with an internal thread 5 extending on a length L measured along longitudinal axis A of said tubular body 2. The internal thread 5 defines peaks 6 and valleys 7 on said inner wall. The major diameter of an internal thread is classically defined as the diameter defined by the valleys.

[0054] On the example shown, as better visible on FIGS. 1 and 2, the internal thread 5 includes a proximal part 5a having a length L4, a distal part 5b having a length L1 and a tapered portion 5c linking the proximal part 5a to the distal part 5b, the tapered portion 5c having a length L2. L1, L2 and L4 are measured along longitudinal axis A, and the overall length L of the internal thread 5 corresponds to the addition of L, L2 and L4. None of the lengths L, L1, L2 and L4 is equal to 0. For example, L1 may range from 1.9 mm to 2.1 mm, L2 may range from 1.9 mm to 2.1 mm, L4 may range from 2.35 mm to 2.55 mm.

[0055] The distal part 5b of the internal thread 5 defines a major diameter D1 while the proximal part 5a of the internal thread defines a major diameter D2. As appears from FIGS. 1 and 2, D2 is strictly less than D1. As shown on FIGS. 1 and 2, the value of the major diameter of the tapered portion 5c of the internal thread 5 varies from that of D1 to that of D2. D2 has a constant value over the length L4. The proximal part 5a of the internal thread 5 is therefore a straight internal thread on length L4.

[0056] With reference to FIG. 3, D1 is the major diameter of the internal thread 5 which is intended to mate the major diameter D3 of the straight external thread 201 provided on the needleless access device 200. Indeed, D1 is identical to D3, so that the straight external thread 201 and the distal part 5b of the internal thread 5 of the adaptor 1 cooperate by regular screwing for threaded engagement. D1 has a constant value over the length L1. The distal part 5b of the internal thread 5 is therefore a straight internal thread on length L1. In the present application, “Straight external thread” means a ridge wrapped around a cylinder in the form of a helix. In particular, the height of the ridge and the diameter of the cylinder are both constant values. In the present application, “straight internal thread” means a ridge located on the inner wall of a tube in the form of a helix. In particular, the height of the ridge and the inner diameter of the tube are both constant values.

[0057] In the example shown on FIG. 3, the straight external thread 201 defines peaks 202 and valleys 203. The major diameter D3 of the external thread 201 is the diameter defined by the peaks 202 and it is constant over the whole length L3 of the external thread 201. The length L3 of the external thread 201 corresponds globally to the length L of the internal thread 5 of the adaptor 1.

[0058] The needleless access device 200 of FIGS. 3 and 4 is shown partially. The straight external thread 201 forms the proximal end of the needleless access device 200. The needleless access device 200 may be any device intended to be connected to the adaptor 1, either for allowing the transfer of a product from the drug delivery device to another medical device free of needle, such as a pocket drip, a vial, an IV (Intra Venous) line, an IM (Intra Muscular) line, a catheter, or on the contrary for safely closing the filled drug delivery device before its use and for preventing any contamination, like for example a closure cap in the storage position of the drug delivery device.

[0059] Since D2 is smaller than D1, the proximal part 5a of the internal thread 5 does not have the correct dimensions for a conventional threaded engagement with the straight external thread 201, the consequences of which will clearly appear later in the description. Preferably, the ratio of D2 to D1 ranges from 0.95 to 0.98.

[0060] Preferably, the ratio of the length L1 of the distal part 5b of the internal thread 5 to the length L2 of the tapered portion 5c measured along the direction of the longitudinal axis A of said tubular body 2 ranges from 0.9 to 1.1, preferably is about 1. In embodiments, the ratio of the length L1 of the distal part 5b to the length L4 of the proximal part 5a ranges from 1.125 to 1.325, preferably is about 1.225. In embodiments, the ratio of the length L2 of the tapered portion 5c to the length L4 of the proximal part 5a ranges from 1.125 to 1.325, preferably is about 1.225.

[0061] As shown on FIG. 4, the adaptor 1 of FIGS. 1-3 is intended to connect the drug delivery device 100 to the needleless access device 200. The connection of the needleless access device 200 to the drug delivery device 100 will now be described with reference to FIGS. 1-4.

[0062] The drug delivery device 100 and the adaptor 1 are aligned and have a common longitudinal axis A. The distal tip 101 of the drug delivery device is conical, distally tapered and it defines an axial passageway 102 for the transfer of a product (not shown) contained therein. The axial passageway 102 is open at its distal end. In embodiments not shown, the outer surface of the distal tip 101 may be provided with an annular groove, or alternatively an annular ridge.

[0063] The distal tip 101 may be made of plastic or glass material. In embodiments, the distal tip 101 is made of glass material. In another embodiment, the distal tip 101, as well as the drug delivery device 100, is made of plastic material selected from crystal clear polymer (CCP), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polystyrene (PS), polypropylene (PP), polyethylene (PE), polyamide (PA) and their combinations.

[0064] In a first step, the adaptor 1 is engaged on the distal tip 101 of the drug delivery device 100 by means of its radially expandable inner rim 3. This step is rendered easy to perform due to the distally tapered shape of the distal tip 101 and to the capability of the inner rim 3 to expand radially. In an embodiment not shown, the engagement of the adaptor and its correct positioning is possible thanks to its appropriate fitting with an annular groove located on the distal tip of the drug delivery device. In other embodiments not shown, the adaptor may be maintained in the proximal part of the distal tip of the drug delivery device thanks to an annular ridge.

[0065] With reference to FIG. 4, the adaptor 1 is then secured on the distal tip 101 of the drug delivery device 100 by friction fitting of the inner rim 3 on the distal tip 101. In particular, the tabs 3a of the inner rim 3 exert a radial inward force on the outer face of the distal tip 101 and they limit the rotation and the translation of the adaptor 1 with respect to the distal tip 101.

[0066] The user then seizes the needleless access device 200 and screws the straight external thread 201 into the internal thread 5 of the adaptor 1. He first screws the straight external thread 201 in the distal part 5b of the internal thread 5 by regular and conventional screwing, as D1 and D3 mate and as the distal part 5b of the internal thread 5 defines a straight internal thread. Then as the tapered portion 5c and the proximal part 5a of the internal thread 5 have different diameters, in particular less than the value of D1, the major diameter of the internal thread 5 on the length L2 of the tapered portion 5c and on the length of the proximal part 5a does not perfectly mate the major diameter D3 of the straight external thread 201 anymore. This difference leads to an increase of the friction between the straight external thread 201 and the tapered portion 5c and proximal part 5a of the internal thread 5 without preventing the complete screwing of the straight external thread 201 in the adaptor 1. Indeed, the screwing remains possible up to the proximal end of the internal thread 5 of the adaptor 1 and the user does not need to increase significantly the torque he exerts in order to obtain a greater friction between the external thread 201 and the internal thread 5. As a consequence, the risks that the adaptor 1 rotates with respect to the distal tip 101 at the time the needleless access device 200 is screwed into the adaptor 1 are greatly limited.

[0067] Then, the user continues screwing the needleless access device 200 into the adaptor 1 on the whole length L of the internal thread 5 until the proximal end of the needleless access device 200 reaches the proximal end of the proximal part of the internal thread 5.

[0068] Surprisingly, the decrease of the major diameter of the internal thread 5 in its proximal part, and for example in its tapered portion, allows a better friction force of the straight external thread of the needleless access device into the adaptor of the invention, and a more stable resulting connection, without having to exert a higher torque for screwing the needleless access device into the adaptor and without preventing the external thread 201 of the needleless access device to be screwed up to the proximal end of the internal thread 5 of the adaptor 1.

[0069] In particular, when the ratio of D2 to D1 ranges from 0.95 to 0.98, the screwing is soft and progressive. Preferably, the ratio of the length L1 of the distal part to the length L2 of the tapered portion ranges from 0.9 to 1.1, preferably is about 1. The resulting connection is particularly stable and secure.

[0070] The risks that the needleless access device 200 screwed into the adaptor 1 of the invention be spontaneously disconnected are therefore greatly limited, even when the distal tip is made of glass or when the needleless access device includes spring biased piece providing high counter forces against the connection. The adaptor of the invention therefore allows a reproducible and safe connection of a needleless access device on said adaptor allowing a secured and reliable passage of fluid from the drug delivery device and the needleless access device. Further, the adaptor of the invention may be compatible with lots of available connectors of the market.

[0071] In addition, the decrease of the major diameter of the internal thread 5 in the proximal part of said internal thread 5 provides for a thicker wall of the proximal part of the tubular body 2, thereby increasing the resistance of said body 2 at the time the needleless access device 200 is screwed therein. Therefore, the adaptor is more resistant.

[0072] The adaptor of the invention allows the reliable connection of a needleless access device on the distal tip of a drug delivery device. The risks that the needleless access device unscrews spontaneously and accidently from the adaptor of the invention are very limited.