Drug delivery device

• US 6,641,561 B1
• Filed: 07/03/2001
• Issued: 11/04/2003
• Est. Priority Date: 10/10/2000
• Status: Expired due to Term

• Current Assignee: Meridian Medical Technologies Incorporated
• Original Assignee: Meridian Medical Technologies Incorporated
• Inventors: Hill, Robert L., Griffiths, Steven, Wilmot, John G.
• Primary Examiner(s): Kennedy, Sharon
• Assistant Examiner(s): Han, Mark K.
• Application Number:
  US09/897,422
• Time in Patent Office: 854 Days
• Field of Search: 604/131, 604/134, 604/135, 604/136, 604/139, 604/190, 604/191, 604/192, 604/82, 604/89, 604/90, 604/91
• US Class Current: 604/136
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 2005/287 by displacing occluding plugs
• CPC Class Codes: A61M 5/2033 Spring-loaded one-shot injectors with or without automatic needle insertion multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287
• CPC Class Codes: A61M 5/2066 comprising means for injection of two or more media, e.g. by mixing
• CPC Class Codes: A61M 5/286 upon internal pressure increase, e.g. pierced or burst A61M5/283 takes precedence
• CPC Class Codes: A61M 5/3145 Filters incorporated in syringes
• CPC Class Codes: A61M 5/34 Constructions for connecting the needle , e.g. to syringe nozzle or needle hub connecting catheter tubes to hubs A61M25/0014
• CPC Class Codes: A61M 5/343 Connection of needle cannula to needle hub, or directly to syringe nozzle without a needle hub A61M5/322 takes precedence

Abstract

The present invention is directed to a drug delivery device. The device includes an interior chamber and a seal structure. In accordance with the present invention, the interior chamber may include a first, liquid medicament compartment and a second medicament compartment. The seal structure is conditionable to permit fluid to pass therethrough upon pressurization of the fluid. The seal structure preferably includes a sealing member which moves from a first sealed position into a second by-pass position upon pressurization of the liquid injection solution in the wet compartment of the housing assembly. Such by-pass movement of the sealing member enables the liquid injection solution to flow through the seal structure into the second ingredient compartment and mix for injection.

Claims

1. An automatic injection device containing a pre-loaded charge of medicament for automatically self-administering the medicament upon actuation thereof, the device comprising:

a housing assembly having an interior chamber, the interior chamber including a dry compartment containing a dry medicament component, and a wet compartment containing a liquid component to be mixed with the dry component;

a seal structure between the dry compartment and the wet compartment, the seal structure being initially in a sealing condition that maintains the dry component sealed from the wet component, the seal structure including at least one flow path formed therein, the seal structure being converted to a mixing condition as a result of activation of the device;

a fluid distributing member disposed between the liquid component and the dry medicament component;

a needle assembly that dispenses the charge of medicament from the housing;

an activation assembly carried by the housing and including a stored energy source, wherein activation of the activation assembly releases the stored energy from the stored energy source, and wherein the release of the stored energy causes a) the seal structure to be converted from the sealing condition to the mixing condition and thereby permit the liquid component to pass through the at least one flow path from the wet compartment to the dry compartment, b) the liquid component to be forced through the fluid distributing member and distributed to the dry component and facilitate mixing and dissolution of the dry medicament component in the liquid component, and c) force the mixed liquid and dry components through the needle assembly.

2. An automatic injection device according to claim 1, wherein said seal structure includes an outer seal member and an inner seal plug movable with respect to said outer seal member from a sealing position which seals the wet compartment from the dry compartment and a mixing position allowing contents of the dry and wet compartments to mix.

3. The automatic injection device according to claim 2, wherein the inner side wall of the outer seal member includes grooves which enable flow of the liquid injection solution around the seal plug and through the seal structure when said seal plug is moved to the mixing position.

4. The automatic injection device according to claim 2, wherein the outer seal member of the seal structure comprises an external sealing member and an internal rigid body configured so as to securingly engage each other.

5. The automatic injection device according to claim 4, wherein the internal rigid body is formed from two rigid members which are annularly welded or bonded together.

6. The automatic injection device according to claim 5, wherein the seal structure further includes a filter or membrane assembly which is clamped between the two rigid members of the internal rigid body, whereby the filter or membrane assembly creates a laminar fluid flow as the liquid injection solution passes from through the seal structure from the wet compartment to the dry compartment.

7. The automatic injection device according to claim 1, wherein the needle assembly comprises a membrane adjacent the dry compartment, wherein the membrane prevents undissolved dry medicament from entering the needle assembly.

8. The automatic injection device according to claim 1, wherein the interior chamber has an open-mouth configuration at the end of the dry compartment adjacent the needle assembly.

9. An automatic injection device according to claim 1, wherein the fluid distributing member includes a filter or membrane assembly which creates a laminar fluid flow as the liquid injection solution passes through the seal structure from the wet compartment to the dry compartment;

wherein the needle assembly comprises a membrane adjacent the dry compartment, wherein the membrane prevents undissolved dry medicament from entering the needle assembly.

10. An automatic injection device according to claim 1, wherein the fluid distributing member comprises a filter.

11. An automatic injection device according to claim 10, wherein the filter creates a laminar fluid flow as the liquid solution passes through the seal structure.

12. An automatic injection device according to claim 1, wherein the seal structure comprises a sealing assembly and a plug member carried by the sealing assembly.

13. An automatic injection device according to claim 12, wherein the sealing assembly has an outer periphery that forms a peripheral seal with an interior wall of the interior chamber, and wherein said plug member is spaced radially inward from the peripheral seal that seals the at least one flow path formed in the seal structure.

14. An automatic injection device according to claim 1, wherein the activation assembly includes a pre-compressed spring.

15. An automatic injection device according to claim 1, wherein the seal structure and the distributing member are integrated into a single assembly.

16. An automatic injection device according to claim 1, wherein the needle assembly is disposed toward a forward end of the housing assembly and the activation assembly is disposed toward a rearward end of the housing assembly, wherein the dry medicament component is disposed forwardly of the liquid component.

17. An automatic injection device according to claim 16, wherein the activation assembly includes a pre-compressed spring that urges a collet rod forwardly through the housing, and wherein forward movement of the collet rod creates sufficient pressure on the liquid component to cause the liquid component to force the seal structure into the mixing condition.

18. An automatic injection device according to claim 17, wherein the seal structure is movable forwardly with respect to the housing as the collet rod is moved forwardly.

19. An automatic injection device according to claim 16, further comprising a dry medicament support structure disposed between the dry medicament component and the needle assembly.

20. An automatic injection device according to claim 1, wherein the seal structure incorporates a burstable membrane.

21. An automatic injection device containing a pre-loaded charge of medicament for automatically self-administering the medicament upon actuation thereof, the device comprising:

a housing assembly having an interior chamber, the interior chamber including a dry compartment containing a dry medicament component, and a wet compartment containing a liquid component to be mixed with the dry component;

a seal structure between the dry compartment and the wet compartment, the seal structure being initially in a sealing condition that maintains the dry component sealed from the wet component, the seal structure being converted to a mixing condition as a result of activation of the device;

the seal structure having a periphery that forms a peripheral seal slidably disposed with respect to an adjacent surface of the interior chamber, the seal structure having an inner seal member spaced radially inward from the peripheral seal that seals at least one flow path formed in the seal structure prior to activation of the device, the inner seal member being convertible from a sealing condition to a mixing condition to enable fluid to flow through the at least one flow path in the seal structure from the wet compartment to the dry compartment;

a needle assembly that dispenses the charge of medicament from the housing;

an activation assembly carried by the housing and including a stored energy source, wherein activation of the activation assembly releases the stored energy from the stored energy source, and wherein the release of the stored energy causes a) the seal structure to be converted from the sealing condition to the mixing condition and thereby permit the liquid component to pass through the at least one flow path, b) force the mixed liquid and dry components through the needle assembly.

22. An automatic injection device according to claim 21, wherein the seal structure incorporates a burstable membrane.

23. An automatic injection device according to claim 21, wherein the inner seal member is a movable plug.

24. An automatic injection device according to claim 21, further comprising a fluid distributing member disposed between the liquid component and the dry medicament component.

25. An automatic injection device according to claim 24, wherein the fluid distributing member comprises a filter.

26. An automatic injection device according to claim 24, wherein the fluid distributing member moves from an initial position spaced rearwardly from the needle assembly to a final position disposed closer to the needle assembly relative to the initial position.

27. An automatic injection device according to claim 21, wherein the seal structure moves from an initial position spaced rearwardly from the needle assembly to a final position disposed closer to the needle assembly relative to the initial position.

28. An automatic injection device according to claim 21, wherein the activation assembly includes a pre-compressed spring.

29. An automatic injection device according to claim 21, wherein the seal structure and the distributing member are integrated into a single assembly.

30. The automatic injection device according to claim 21, wherein the needle assembly comprises a membrane adjacent the dry compartment, wherein the membrane prevents undissolved dry medicament from entering the needle assembly.

31. The automatic injection device according to claim 21, wherein the interior chamber has an open-mouth configuration at the end of the dry compartment adjacent the needle assembly.

32. An automatic injection device according to claim 21, wherein the seal structure further includes a filter or membrane assembly which creates a laminar fluid flow as the liquid injection solution passes through the seal structure from the wet compartment to the dry compartment;

wherein the needle assembly comprises a membrane adjacent the dry compartment, wherein the membrane prevents undissolved dry medicament from entering the needle assembly.

33. A method of administering a pre-loaded charge of medicament, comprising:

providing an automatic injection device having a housing assembly, wherein the housing assembly includes an interior chamber having a dry compartment containing a dry medicament component, and a wet compartment containing a liquid component to be mixed with the dry component, the injection device further includes a seal structure between the dry compartment and the wet compartment, the seal structure being initially in a sealing condition that maintains the dry component sealed from the wet component, the seal structure being converted to a mixing condition as a result of activation of the device, a fluid distributing member disposed between the liquid component and the dry medicament component, a needle assembly that dispenses the charge of medicament from the housing, and an actuating assembly having stored energy source;

locating the automatic injection device at a desired location on a recipient; and

actuating the activation assembly carried by the housing to release the stored energy from the stored energy source such that the release of the stored energy causes a) the seal structure to be converted from the sealing condition to the mixing condition and thereby permit the liquid component to pass there through, b) the liquid component to be forced through the fluid distributing member and distributed to the dry component and facilitate mixing and dissolution of the dry medicament component in the liquid component, and c) force the mixed liquid and dry components through the needle assembly.