Drug Delivery Device with Coated End-Piece

Abstract

A drug delivery device includes a reservoir for containing a medical product, a distally projecting end-piece having an outer surface and a total length measured along a longitudinal axis of said end-piece, said end-piece defining an axial passageway for the transfer of said medical product contained in said reservoir, wherein a gripping surface is provided on a portion of said outer surface, said portion being located in a distal region of said end-piece, the length of said portion representing at most 40%, preferably less than 33%, of the total length of the end-piece. An assembly includes such a drug delivery device and an adaptor intended to be mounted onto the end-piece.

Claims

1. A drug delivery device comprising: a reservoir for containing a medical product, and a distally projecting end-piece having an outer surface and a total length measured along a longitudinal axis of said end-piece, said end-piece defining an axial passageway for a transfer of said medical product contained in said reservoir, wherein a gripping surface is provided on a portion of said outer surface, said portion being located in a distal region of said end-piece, a length of said portion representing at most 40% of the total length of the end-piece.

2. The drug delivery device according to claim 1, wherein a distal edge of said portion is located at least at 0.5 mm from a distal end of the end-piece.

3. The drug delivery device according to claim 1, wherein the end-piece has a frustoconical shape, an outer diameter of the distal end of said end-piece being less than an outer diameter of a proximal end of said end-piece.

4. The drug delivery device according to claim 1, wherein the total length of said end-piece varies from 7.5 mm to 7.8 mm, the length of said portion varies from 2.00 mm to 2.70 mm.

5. The drug delivery device according to claim 4, wherein said length of said portion is around 2.35 mm.

6. The drug delivery device according to claim 1, wherein the gripping surface results from a modification of a surface of a material forming the end-piece.

7. The drug delivery device according to claim 6, wherein the modification is provided by a technique selected from abrasion technique, forming treatment, plasma treatment, laser treatment and combinations thereof, applied on said portion.

8. The drug delivery device according to claim 1, wherein the gripping surface is part of a supplementary piece provided on said portion.

9. The drug delivery device according to claim 8, wherein the gripping surface is an outer surface of an elastomeric sleeve attached or molded to said portion of said end-piece.

10. The drug delivery device according to claim 1, wherein the gripping surface is provided by application of a coating on said portion.

11. The drug delivery device according to claim 10, wherein the coating is a ceramic coating comprising borosilicate-zinc based fits.

12. The drug delivery device according to claim 10, wherein the end-piece is made of glass.

13. The drug delivery device according to claim 1, wherein the end-piece comprises an annular groove located in a proximal region on its outer surface.

14. An assembly comprising a drug delivery device according to claim 1, and an adaptor comprising a collar mountable on said-end-piece.

15. The assembly according to claim 14, wherein the collar is provided with an inner rim engageable in the annular groove, when the adaptor is mounted on the end-piece.

16. The drug delivery device according to claim 1, wherein the length of said portion represents less than 33% of the total length of the end-piece.

17. The drug delivery device according to claim 1, wherein a distal edge of said portion is located at least 1 mm from a distal end of the end-piece.

Description

[0039] The drug delivery device and assembly of the invention will now be further described in reference to the following description and attached drawings in which:

[0040] FIG. 1 is a partial side view of an embodiment of the drug delivery device of the invention,

[0041] FIG. 2 is a partial side view of an adaptor being mounted onto the end-piece of the drug delivery device of FIG. 1,

[0042] FIG. 3 is a partial side view of the assembly of FIG. 2 once the adaptor is mounted onto the end-piece of the drug delivery device,

[0043] FIG. 4 is a partial side view of a connector connected to the assembly of FIG. 3,

[0044] FIG. 5 is a partial side view of another embodiment of an end-piece of the drug delivery device of the invention.

[0045] With reference to FIG. 1 is shown partially a drug delivery device 100 of the invention comprising a reservoir 10 having a distally projecting end-piece 20 aligned on a longitudinal axis A.

[0046] The reservoir 10 is intended to contain a medical product to be delivered to a patient. The reservoir 10 may be formed of any material suitable for storing a product such as a medicine or drug. It may be made of glass or plastic materials. On the example shown, the reservoir 10 has the global shape of a syringe body and comprises a tubular barrel 11. The tubular barrel 11 is open at its proximal end (not shown) for example for receiving a stopper. The end-piece 20 comprises an axial passage way (not visible on the figure) for the transfer of the product contained in the reservoir. For example, the product may be transferred from the reservoir to another medical device, such as a connector to an IV line, etc. . . . .

[0047] On FIG. 1, the end-piece 20 has a frustoconical shape, the outer diameter of its distal end 20a being less than the outer diameter of its proximal end 20b. The end-piece 20 has a distal region 21a and a proximal region 21b.

[0048] For example, the end-piece is a male luer according to a standard, for example ISO594 or ISO11040 and the slope of the cone is 6%. In such a case, the total length L.sub.T of the end-piece may vary from 7.5 mm to 7.8 mm.

[0049] The end-piece may be made of glass or of plastic material.

[0050] In the proximal region of its outer surface, the end-piece 20 comprises an annular groove 24, provided with an axial surface 24a, the function of which will be explained later.

[0051] In embodiments not shown, the outer surface of the end-piece is free of any annular groove or relief.

[0052] On a portion 22 of the outer surface of its distal region 21a, the end-piece 20 is provided with a gripping surface, under the form of a coating 23 on the example shown. The coating 23 is capable of increasing the roughness of the outer surface of the end-piece 20.

[0053] For example, the coating is a ceramic coating comprising borosilicate-zinc based frits. Such a coating confers additional roughness to the outer surface of the end-piece. Any coating composition which, when cured or dried, increases the roughness of the surface of the end-piece so that the force required to remove the connector from the end-piece, on which it is removably connected by a frictional interference fit, is greater than the force required to remove the connector from an identically sized end-piece without the coating, may be contemplated in the present invention. Examples of coating compositions are mixtures of borosilicate and zinc based frits.

[0054] The coating may be obtained by deposition of the ceramic solution onto the outer surface of the end-piece by means of a wheel soaking in suspension in the solution. A pre-defined layer of ceramic coating in the range of no more than 150 μm width, for example ranging from 10 to 150 μm width, is deposited onto the outer surface of the end-piece. Then, the drug delivery device is put in an annealing oven. The ceramic coating is dried cured.

[0055] The coating may be uniform in nature. It may be applied onto the outer surface of the end-piece under the form of a specific pattern, said pattern being present on the wheel. The pattern may include any design that allows increasing the roughness of the outer surface of the end-piece as described above.

[0056] In other embodiments not shown, the gripping surface, formed of the coating 23 in the example of the figures, may result from a modification of the surface of the material forming the end-piece, such as glass or plastic materials. For example, the modification may be provided by a technique selected from abrasion technique, plasma treatment, laser treatment and combinations thereof, applied on said portion. Alternatively or in combination, the gripping surface may be part of a supplementary piece provided on said portion. For example, the gripping surface may be the outer surface of an elastomeric sleeve attached, molded or co-molded, to said portion of said end-piece, depending on the nature, i.e. glass or plastic, of said portion.

[0057] With reference to FIG. 1, the coating 23 is located in the distal region 21a of the outer surface of the end-piece 20. In addition, the length L.sub.C of the portion 22 measured along the longitudinal axis A represents at most 40%, preferably less than 33%, of the total length L.sub.T of the end-piece also measured along longitudinal axis A.

[0058] The distal edge 22a of the portion 22 on which the coating 23 extends may be located at around 0.5 mm, preferably at 1 mm, from the distal end 20a of the end-piece 20. As appears on FIG. 1, the distal edge 22a is proximally spaced with respect to the distal end 20a of the end-piece 20.

[0059] For example, the total length L.sub.T of the end-piece 20, measured from its proximal end 20b to its distal end 20a, along the longitudinal axis A, may vary from 7.5 to 7.8 mm. In such a case, the length L.sub.C of the portion 22 on which the coating extends may for example vary from 2.00 to 2.70 mm. For example, this length L.sub.C may be 2.35 mm. In such a case, the portion on which the coating 23 extends represents around 30-32% of the total length L.sub.T.

[0060] On FIG. 1, the coating has the shape of an annular band and said coating 23 extends on the totality of the portion 22, as the surface of the portion 22 is common with the surface of the coating 23. With reference to FIG. 5, is shown another embodiment of an end-piece of a drug delivery device of the invention. The references designating the same elements as in FIG. 1 have been maintained. On the embodiment of FIG. 5, the coating 123 has the shape of a band forming waves. The surface of the portion 122 on which the coating 123 extends is therefore greater than the surface of the coating. Anyway, the length L.sub.C of the portion 122 still represents at most 40% of the total length of the end-piece.

[0061] With reference to FIG. 2, is shown the mounting of an adaptor 30 on the end-piece 20. The adaptor 30 comprises a collar 31 provided at its proximal end with an inner rim 32 having an axial surface 32a. As will be clear from the description below, the adaptor 30 is intended to be fixed onto the end-piece 20 by frictional interference fit between the inner rim 32 and the annular groove 24 of the end-piece 20.

[0062] The inner surface of the collar 31 is provided with an inner thread 33, the function of which will be explained later. The mounting of the adaptor 30 onto the end-piece 20 is facilitated by the appropriate location of the coating 23 on the end-piece 20 and also by the small length Lc of the coated part of the end-piece, said length Lc representing namely less than 40%, preferably less than 33%, of the total length L.sub.T of the end-piece. In particular, as shown on this FIG. 2, it is possible to slide the adaptor 30 over the end-piece 20 while avoiding that the inner rim 32 of the adaptor contacts the coating 23. Neither the coating 23 nor the axial surface 32a of the inner rim 32 of the adaptor 30 are damaged by mutual contact, since such mutual contact does not take place.

[0063] In particular, because of the location of the distal edge 22a of the portion 22 on which the coating 23 extends, at least 0.5 mm, preferably 1 mm, away from the distal end 20a of the end-piece 20 in the proximal direction, the risk that the adaptor 30 contacts the coating 23 when said adaptor 30 is approached towards the end-piece 20 is very limited. In addition, thanks to this configuration, no particles are generated and contamination is therefore avoided.

[0064] For example, the inner diameter of the inner rim 32 is greater than the greatest outer diameter of the portion 22 so that contact between the inner rim 32 and the outer surface of the portion 22 is avoided when the adaptor is being mounted on the end-piece, and potential damage likely to occur from such a contact is therefore prevented. In particular, emission of particles which could result from the contact between the inner rim 32 and the outer surface of the portion 22 at the time the adaptor is being mounted on the end-piece is avoided. The quality of the drug delivery device therefore remains high.

[0065] With reference to FIG. 3, the adaptor 30 has been fully mounted onto the end-piece 20. The inner rim 32 of the adaptor 30 is now engaged into the annular groove 24 of the end-piece 20, with its axial surface 32a in contact with the axial surface 24a of said groove 24. The adaptor 30 is therefore fixed onto the end-piece 20 by friction forces present between the axial surface 32a of the inner rim 32 and the axial surface 24a of the annular groove 24. In particular, because the axial surface 32a of the inner rim 32 has not been in contact with the coating 23 during the mounting of the adaptor 30 onto the end-piece 20, the adaptor 30 does not lose its capability of remaining in friction fit with the end-piece. The fixation of the adaptor 30 on the end-piece 20 is therefore reliable. A connector may then be threaded into the adaptor safely.

[0066] With reference to FIG. 4, is shown a connector 40, under the form of the proximal end of an Intra venous line, which has been threaded into the adaptor 30.

[0067] The connector 40 comprises a female luer 41 having an inner surface 42. On its outer surface 43, the female luer 41 is provided with an outer thread 44 capable of cooperating with the inner thread 33 of the adaptor 30.

[0068] Because the adaptor 30 is well fixed to the end-piece 20 thanks to the friction forces between the end-piece 20 and the adaptor 30 as described above, the threading of the connector 40 into the adaptor 30 is facilitated. Besides, the coating 23 is in tight contact with the inner surface 42 of the female luer of the connector 40. This tight contact between the coating 23 of the end-piece 20 and the inner surface 42 of the female luer 41 provides additional friction forces between the adaptor 30 and the end-piece 20, thereby enhancing the reliability of the connection there between. In particular, when the connector 40 is threaded into the adaptor 30, the presence of the coating 23 increases the resistance of the adaptor 30 to the torque provided by the user in view of threading the connector 40 into the adaptor 30. As a consequence, the adaptor 30 remains immobile and does not rotate with respect to the end-piece 20, contrarily to what may happen with the end-pieces of the prior art free of any gripping surface. The threading of the connector 40 into the adaptor 30 is therefore not only facilitated but also more reliable and secure.

[0069] A test measuring the pull out force (POF) of a drug delivery device of the invention and of a drug delivery device of the prior art has been completed. The drug delivery device of the invention is provided with the end-piece of FIG. 1, in which the gripping surface is a ceramic coating comprising borosilicate-zinc based frits. The end-piece is a frustoconical tip having a 6% taper, made of glass. An adaptor such as the adaptor 30 of FIG. 2 is mounted on the frustoconical tip.

[0070] The comparative drug delivery device is provided with a standard frustoconical tip having a 6% taper, made of glass, free of any gripping surface. An adaptor such as the adaptor 30 of FIG. 2 is mounted on the frustoconical tip.

[0071] The Pull Out Force test consists in connecting a connector by threading the connector into the adaptor mounted on the frustoconical tip by applying a torque of 12 Ncm by automatic torque-meter combined with an axial force of 20N and then measuring the force to remove the adaptor from the frustoconical tip by pulling the connector while the drug delivery device is fixed.

[0072] The median value of the force in Newton necessary for achieving the aim of the Pull Out Force test with the drug delivery device of the invention was 135 N, whereas that required for the comparative drug delivery device was 58 N. These results show that the reliability of the connection between the end-piece and the connector is increased in the drug delivery device compared to a drug delivery device of the prior art.

[0073] A test measuring the torque for disconnecting a connector from a drug delivery device of the invention and from a drug delivery device of the prior art has been completed. The drug delivery device of the invention and the comparative drug delivery device are identical to those described above for the Pull Out Force test.

[0074] The Torque test consists in first connecting a connector by threading the connector into the adaptor mounted on the frustoconical tip by applying a torque of 12 Ncm by automatic torque-meter combined with an axial force of 20 N. Then, an unscrewing torque of 2 Ncm is applied on the connector during 10 seconds, and the potential disconnection is checked. The unscrewing torque is then increased until disconnection of the connector.

[0075] The median value of the torque necessary for achieving the aim of the test with the drug delivery device of the invention was 23 Ncm while that required for the comparative drug delivery device was 14 Ncm. These results show that the reliability of the connection between the end-piece and the connector is increased in the drug delivery device compared to a drug delivery device of the prior art.

[0076] The drug delivery device of the invention allows increasing the reliability of a connection between the end-piece of such a drug delivery device and a connector, especially in the case when such drug delivery device is intended to be used in combination with an adaptor such as a luer lock adaptor.