Implant cannula having an implant and a method for securing implants in an injection cannula

Abstract

The application provides an injection cannula having an implant which is detachably secured in the cannula. The application also provides a method for detachably securing an implant in an injection cannula.

Claims

1. A method for detachably securing an implant in an injection cannula comprising (a) introducing a physiologically tolerable material into an injection cannula, wherein the physiologically tolerable material comprises a curable polymer material, (b) distributing the physiologically tolerable material in the injection cannula when the physiologically tolerable material is flowable, (c) curing the physiologically tolerable material, and (d) introducing an implant into the injection cannula comprising the cured physiologically tolerable material, wherein the implant is in a form of a cylindrical rod comprising a plastic and active ingredient matrix and steps (a)-(d) are carried out prior to implantation into a patient.

2. The method of claim 1, wherein a portion of the physiologically tolerable material introduced into the injection cannula is removed from the injection cannula before introducing the implant into the injection cannula.

3. The method of claim 2, wherein the portion of the physiologically tolerable material is removed from the injection cannula before curing the physiologically tolerable material.

4. The method of claim 2, wherein the portion of the physiologically tolerable material is removed from the injection cannula after curing the physiologically tolerable material.

5. The method of claim 1, wherein the injection cannula has a lateral opening.

6. The method of claim 5, wherein the implant is detachably secured in a region of the lateral opening of the injection cannula.

7. The method of claim 6, wherein the physiologically tolerable material is introduced into the injection cannula through the lateral opening of the injection cannula.

8. The method of claim 1, wherein the implant comprises goserelin, leuprorelin, anastrozole, risperidone or octreotide.

9. The method of claim 1, wherein the implant comprises polymers or copolymers of lactic acid and/or glycolic acid.

10. An injection cannula comprising: an implant in the form of a cylindrical rod comprising a plastic and active ingredient matrix; wherein prior to implantation into a patient, the implant is detachably secured in the injection cannula by a physiologically tolerable material that is introduced into the injection cannula, the physiologically tolerable material comprises a curable polymer material, wherein prior to implantation into the patient, the physiologically tolerable material is distributed in the injection cannula when the physiologically tolerable material is flowable, wherein prior to implantation into the patient, the physiologically tolerable material is cured, and wherein prior to implantation into the patient, the implant is introduced into the injection cannula when the physiologically tolerable material is cured.

11. The injection cannula of claim 10, further comprising a lateral opening.

12. The injection cannula of claim 11, wherein the implant is detachably secured in the injection cannula via the physiologically tolerable material and wherein said implant is secured on an inner wall of the injection cannula that is opposite to the lateral opening of the injection cannula.

13. The injection cannula of claim 10 wherein the injection cannula is a customary injection cannula.

14. The injection cannula of claim 13 wherein the injection cannula comprises special steel.

15. The injection cannula of claim 14 wherein the injection cannula has a siliconized surface.

16. The injection cannula of claim 10, wherein the implant is detachably secured in the injection cannula over at least part of at least one longitudinal side of the injection cannula with the physiologically tolerable material.

17. The injection cannula of claim 16, wherein the implant is detachably secured in the injection cannula over up to 50% of the surface area of the at least one longitudinal side.

18. The injection cannula of claim 16, wherein the implant is detachably secured in the injection cannula over at least one point on the surface of at least one longitudinal side.

19. The injection cannula of claim 10, wherein the physiologically tolerable material has a layer thickness of from 0.1 to 1.2 mm.

20. The injection cannula of claim 11, wherein the implant is arranged in a region of the lateral opening of the injection cannula.

21. The injection cannula of claim 10, wherein the implant comprises goserelin, leuprorelin, anastrozole, risperidone or octreotide.

22. The injection cannula of claim 10, wherein the implant comprises polymers or copolymers of lactic acid and/or glycolic acid.

23. The injection cannula of claim 10, wherein the implant does not include any material identical to the physiologically tolerable material.

Description

EXAMPLES

(1) The following materials were used in the examples:

(2) Injection cannula: special steel, silicone-coated, length 32 mm, internal diameter 1.4 mm, external diameter 1.6 mm with a lateral opening having a diameter of 1.2 mm at a distance of 26 mm from the tip of the cannula and a luer-lock connecting system, for example obtainable from the company SFM.

(3) Implant: 151.5 mm made of 79.5%, by weight, poly-lactide-co-glycolide 50:50 and 20.5%, by weight, goserelin.

(4) Semi-solid material: a mixture of polyethylene glycol which was prepared as follows: 1.23 g of PEG 400 and 1.23 g of PEG 1000 were melted together, with stirring, at 80 C. and, with further stirring, allowed to cool to room temperature. An ointment-like mass is formed. The production of PEG ointments by mixing various kinds of PEG is known to the person skilled in the art.

(5) Curable polymer material: silicone rubber RTV-1, for example obtainable from the company Wacker Chemie under the brand name Elastosil E41.

(6) Stylet: made of special steel, diameter 1.0 mm, for example obtainable from the company SFM.

(7) Application system: see Example 6.

Example 1

(8) A droplet of curable polymer material was introduced into an injection cannula in the region between the lateral opening and the luer-lock connecting system (above the opening or in the portion of the cannula remote from the tip). The curable polymer material was then distributed in the cannula using a stylet. The amount of polymer material introduced was determined as 10 mg by differential weighing. The polymer material was cured overnight. An implant was then introduced into the cannula from the luer-lock side and displaced using a stylet until it was located in the region of the lateral opening (visual inspection).

(9) The implant could not be removed from the cannula by vigorous shaking. Using an application system it was possible to expel (inject) the implant out of the cannula without problems, the expelled implant exhibiting no traces of silicone.

Example 2

(10) Example 1 was repeated with the same result, but the amount of polymer material introduced was determined as 13 mg.

Example 3

(11) A droplet of semi-solid material was introduced into an injection cannula in the region between the lateral opening and the tip of the cannula. The amount of semi-solid material introduced was determined as 4.2 mg by differential weighing. An implant was then introduced into the cannula from the luer-lock side. It was not necessary to use a filling aid (stylet).

(12) Vigorous shaking did not cause the implant to drop out of the cannula. Using an application system it was possible to expel (inject) the implant out of the cannula without problems, 4.1 mg of the semi-solid material being detected on the expelled implant by differential weighing.

Example 4

(13) Example 3 was repeated with the same result, but the amount of semi-solid material introduced was determined as 5.6 mg, of which 5.0 mg were detected on the expelled implant.

Example 5

(14) Example 3 was repeated with the same result, but the amount of semi-solid material introduced was reduced to 0.8 mg, of which 0.8 mg was detected on the expelled implant.

Example 6

(15) A commercially available syringe (5 ml) was provided with a 0.940 mm cannula, the tip of which (bevel point) was removed with pincers in order to obtain a flat end, and filled with curable polymer material. Using this syringe a droplet of approximately 1 l of the polymer material was introduced into an injection cannula on the inner wall of the cannula opposite from the lateral opening. The amount of polymer material introduced was determined as 1 mg by differential weighing. The polymer material was cured overnight. An implant was then introduced into the cannula from the luer-lock side and displaced using a stylet until it was located in the region of the lateral opening (visual inspection).

(16) The implant could not be dislodged from the cannula by vigorous shaking. Using an application system it was possible to expel (inject) the implant out of the cannula without problems, the expelled implant exhibiting no traces of silicone on the surface.