Transdermal medicament patch and active electrode for same

• US 20080305154A1
• Filed: 06/08/2007
• Published: 12/11/2008
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: ActivaTek Inc. (North Coast Medical, Inc.)
• Original Assignee: ActivaTek Inc. (North Coast Medical, Inc.)
• Inventors: Yanaki, Jamal S.
• Granted Patent: US 8,197,844 B2
• Time in Patent Office: Days
• US Class Current: 424/449
• CPC Class Codes: A61F 13/00051 Accessories for dressings
• CPC Class Codes: A61F 13/02 Adhesive bandages or dressings
• CPC Class Codes: A61F 2013/00285 medication confinement
• CPC Class Codes: A61F 2013/00417 pierced by needle
• CPC Class Codes: A61F 2013/00442 using electrodes
• CPC Class Codes: A61F 2013/00489 for bracing or strapping
• CPC Class Codes: A61F 2013/00646 Medication patches, e.g. transcutaneous
• CPC Class Codes: A61F 2013/00906 for transcutaneous or transdermal drugs application
• CPC Class Codes: A61F 2013/00919 for physical therapy, e.g. cold or magnetic
• CPC Class Codes: A61F 2013/00948 Ph, e.g. acid
• CPC Class Codes: A61F 2013/00961 electrical conductivity
• CPC Class Codes: A61N 1/30 Apparatus for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body, or cataphoresis

Abstract

A transdermal medicament patch includes a biocompatible substrate having a therapeutic face on one side configured for disposition against the skin of a patient, a biocompatible adhesive on the therapeutic face, a planar medicament matrix covering a portion of the therapeutic face, and a release liner covering the portion of therapeutic that is not obscured by the medicament matrix. An aperture formed through the release sheet affords direct access by medicament to the entire surface of the medicament matrix opposite from the therapeutic face of the substrate. An active electrode positioned between the medicament matrix and the therapeutic face of the substrate includes an electrically conductive backing layer positioned against the therapeutic face of the substrate and a pH-control layer covering less than all of the side of the backing layer opposite from the therapeutic face of the substrate. One active electrode design criterion relates the relative size of the pH-control layer to the size of the backing layer; another relates the size of portion of the area of the backing layer that is free of the pH-control lawyer to the size of the pH-control layer. The pH-control layer is made of an electrically conductive material capable of moderating changes in the hydrogen-ion concentration in the medicament matrix during iontophoretic current flow. An electrical contact electrically coupled through the substrate to the backing layer includes a hollow, electrically conductive snap fitting having an open end and a cooperating stud that is inserted into the open end of the snap.

Claims

1. A transdermal medicament patch comprising:

(a) a flexible, planar biocompatible substrate having a therapeutic face on one side thereof configured for disposition against the skin of a patient;

(b) a biocompatible adhesive on said therapeutic face of said substrate, said adhesive being sufficient in extent to releasably retain said patch on the person of the patient, when said therapeutic face of said substrate is disposed against the skin of the patient;

(c) a planar medicament matrix on said therapeutic face of said substrate, the portion of said therapeutic face of said substrate thereby obscured by said medicament matrix defining a concealed portion of said therapeutic face, and the portion of said therapeutic face other than said concealed portion thereof defining an exposed portion of said therapeutic face, when permeated by medicament said medicament matrix effecting electrically conductive engagement with the skin of a patient when said patch is releasably retained on the person of the patient; and

(d) a release liner covering said exposed portion of said therapeutic face of said substrate and affording direct access by medicament to the entire surface of the side of said medicament matrix opposite from said concealed portion of said therapeutic face.

2. A medicament patch as recited in claim 1, wherein said adhesive covers the entirety of said exposed portion of said therapeutic face.

3. A medicament patch as recited in claim 1, wherein said medicament matrix is retained on said concealed portion of said therapeutic face by said adhesive.

4. A medicament patch as recited in claim 1, wherein said adhesive covers the entirety of said therapeutic face of said substrate.

5. A medicament patch as recited in claim 1, wherein medicament used to permeate said medicament matrix has a negative polarity.

6. A medicament patch as recited in claim 1, wherein medicament used to permeate said medicament matrix has a positive polarity.

7. A medicament patch as recited in claim 1, further comprising an active electrode positioned between said medicament matrix and said therapeutic face of said substrate interior the periphery of said medicament matrix.

8. A medicament patch as recited in claim 7, wherein said active electrode comprises:

(a) an electrically conductive backing layer positioned against said concealed portion of said therapeutic face of said substrate, the surface of said backing layer on the side thereof opposite from said therapeutic face of said substrate defining a driving face of said backing layer; and

(b) a pH-control layer on said driving face of said backing layer covering less than all of said driving face, said pH-control layer and the portion of said driving face free of said pH-control layer together electrically engaging said medicament matrix, said pH-control layer being made of an electrically conductive material capable of moderating changes in the hydrogen-ion concentration in said medicament matrix, when said therapeutic face of said substrate is disposed against the skin of the patient, and an electrical potential is imposed between said backing layer and the skin of the patient remote from said medicament matrix.

9. A medicament patch as recited in claim 8, wherein said backing layer is retained against said concealed portion of said therapeutic face by said adhesive.

10. A medicament patch as recited in claim 8, wherein said active electrode further comprises an electrical contact electrically coupled to the surface of the side of said backing layer opposite from said driving face thereof, and said electrical contact comprises:

(a) a hollow, electrically conductive snap fitting having an open end; and

(b) a cooperating, electrically insulative stud, in the assembled condition of said electrical contact said stud being inserted into said snap through said open end thereof.

11. A transdermal medicament patch comprising:

(a) a flexible, planar biocompatible substrate having a therapeutic face on one side thereof configured for disposition against the skin of a patient;

(b) a biocompatible adhesive on said therapeutic face of said substrate;

(c) an absorbent medicament matrix non-releasably retained by said adhesive to a portion of said therapeutic face of said substrate, said medicament matrix when wetted with a medicament solution effecting electrically conductive engagement with the skin of a patient when said therapeutic face is disposed there against; and

(d) a release liner having formed therethrough a medicament matrix aperture closely similar in size and shape to the periphery of said medicament matrix, said release liner covering all of said adhesive on said therapeutic face of said substrate exterior of said periphery of said medicament matrix, and said medicament matrix projecting through and filling said medicament matrix aperture.

12. A medicament patch as recited in claim 11, further comprising an active electrode positioned between said medicament matrix and said therapeutic face of said substrate interior the periphery of said medicament matrix.

13. A medicament patch as recited in claim 12, wherein said active electrode comprises:

(a) an electrical contact;

(b) a pH-control layer comprised of an electrically conductive material capable of moderating changes in the hydrogen-ion concentration in the reservoir, when said patch is disposed against the skin of the patient, and an electrical potential is imposed between said electrical contact and the skin of a patient at a location remote from said medicament matrix; and

(c) an electrically conductive backing layer sandwiched between said electrical contact and said pH-control layer, the surface of said backing layer contacted by said pH-control layer defining a driving face of said backing layer, and said pH-control layer covering less than all of said driving face.

14. A medicament patch as recited in claim 13, wherein said pH-control layer is comprised of a material capable of precluding electrolysis in the reservoir, when an electrical potential is imposed between said backing layer and the skin of a patient with the medicament patch disposed there against.

15. A medicament patch as recited in claim 13, wherein said pH-control layer is comprised of a material capable of neutralizing electrolysis products in the reservoir, when an electrical potential is imposed between said backing layer and the skin of a patient with the medicament patch disposed there against.

16. A medicament patch as recited in claim 13, wherein said active electrode further comprises an electrical contact electrically coupled to the surface of the side of said backing layer opposite from said driving face thereof.

17. A medicament patch as recited in claim 16, wherein said electrical contact comprises an assembly of:

(a) a hollow, electrically conductive snap fitting having an open end; and

(b) a cooperating, stud, in the assembled condition of said electrical contact said stud being inserted into said snap through said open end thereof.

18. A medicament patch as recited in claim 17, wherein said stud is electrically insulative.

19. A medicament patch as recited in claim 18, wherein said stud comprises:

(a) a shaft configured for press fit insertion through said open end of said snap fitting; and

(b) a generally planar flange secured to one end of said shaft.

20. A medicament patch as recited in claim 19, wherein, in said assembled condition of said electrical contact, said flange of said stud is positioned on the side of said pH-control layer opposite from said driving face of said backing layer, and said shaft of said stud passes through said pH-control layer and said backing layer to enter said open end of said snap fitting.

21. An active electrode for driving medicament into the skin of a patient from a solution of the medicament contained in a reservoir on the therapeutic face of the substrate of a transdermal medicament patch, the reservoir being disposed interior of the periphery of the therapeutic face of the substrate, and the reservoir electrically conductively engaging the skin of the patient when the therapeutic face of the substrate is disposed there against, said active electrode comprising:

(a) a planar backing layer positioned between the reservoir and the substrate and comprised of an electrically conductive material, the surface of the side of said backing layer remote from the substrate defining a driving face of said backing layer; and

(b) a pH-control layer on said driving face of said backing layer covering less than all of said driving face, said pH-control layer and the portion of said driving face free of said pH-control layer together electrically engaging the reservoir, said pH-control layer being comprised of an electrically conductive material capable of moderating changes in the hydrogen-ion concentration in the reservoir, when said patch is disposed against the skin of the patient, and an electrical potential is imposed between said backing layer and the skin of the patient at a location remote from the reservoir.

22. An active electrode as recited in claim 21, wherein said pH-control layer is comprised of a material capable of precluding electrolysis in the reservoir, when said patch is disposed against the skin of the patient, and an electrical potential is imposed between said backing layer and the skin of the patient at a location remote from the reservoir.

23. An active electrode as recited in claim 22, wherein said pH-control layer is comprised of a mixture of silver and silver-chloride.

24. An active electrode as recited in claim 21, wherein said pH-control layer is comprised of a material capable of neutralizing electrolysis products in the reservoir, when said patch is disposed against the skin of the patient, and an electrical potential is imposed between said backing layer and the skin of the patient at a location remote from said reservoir.

25. An active electrode as recited in claim 24, wherein said pH-control layer is comprised of potassium phosphate.

26. An active electrode as recited in claim 21, wherein the ratio of the area of said portion of said backing layer free of said pH-control layer to said pH-control layer is in a range from about 0.20 to about 8.00.

27. An active electrode as recited in claim 21, wherein the periphery of said pH-control layer is geometrically similar to the periphery of said backing layer.

28. An active electrode as recited in claim 21, wherein said pH-control layer comprises a plurality of discrete, unconnected pH-control layer components covering a corresponding plurality of discrete, unconnected portions of said driving face of said backing layer.

29. An active electrode as recited in claim 21, wherein said pH-control layer comprises a single, connected layer having an aperture formed therethrough, said driving face of said backing layer being free of said pH-control layer at said aperture.

30. An active electrode as recited in claim 29, wherein said pH-control layer has a plurality of apertures formed therethrough, said driving face of said backing layer being free of said pH-control layer at each of said plurality of said apertures.

31. An active electrode as recited in claim 30, wherein:

(a) said pH-control layer comprises a field of intersecting grid lines; and

(b) each of said plurality of apertures is bounded by plural of said grid lines.

32. An active electrode as recited in claim 21, wherein:

(a) the periphery of said pH-control layer coincides with the periphery of said backing layer; and

(b) said pH-control layer has an aperture formed therethrough, said driving face of said backing layer being free of said pH-control layer at said aperture.

33. An active electrode as recited in claim 21, wherein said pH-control layer is disposed interior of the periphery of said driving face of said backing layer.

34. An active electrode as recited in claim 33, wherein a portion of the periphery of said pH-control layer is tangential to the periphery of said driving face of said backing layer.

35. An active electrode as recited in claim 21, wherein a portion of said pH-control layer extends exterior of the periphery of said driving face of said backing layer.

36. An active electrode as recited in claim 21, further comprising an electrical contact electrically coupled to the surface of the side of said backing layer opposite from said driving face thereof.

37. An active electrode as recited in claim 36, wherein said electrical contact comprises an assembly of:

(a) an electrically conductive snap fitting; and

(b) a stud receivable interior of said snap fitting.

38. An active electrode as recited in claim 37, wherein said stud of said electrical contact is electrically insulative.

39. An active electrode for driving medicament from a reservoir carried on the substrate of a transdermal medicament patch, said active electrode being positionable during use between the reservoir and the substrate interior the periphery of the reservoir, said active electrode comprising:

(a) an electrical contact;

(b) a pH-control layer comprised of an electrically conductive material capable of moderating changes in the hydrogen-ion concentration in the reservoir, when said patch is disposed against the skin of the patient, and an electrical potential is imposed between said backing layer and the skin of the patient at a location remote from the reservoir; and

(c) an electrically conductive backing layer sandwiched between said electrical contact and said pH-control layer, the surface of said backing layer contacted by said pH-control layer defining a driving face of said backing layer, and said pH-control layer covering less than all of said driving face.

40. An active electrode as recited in claim 39, wherein said electrical contact is electrically coupled to the surface of the side of said backing layer opposite from said driving face thereof, and said electrical contact comprises an assembly of:

(a) an electrically conductive snap fitting; and

(b) a stud receivable interior of said snap fitting.

41. An active electrode as recited in claim 39, wherein said stud of said electrical contact is electrically insulative.

42. An active electrode as recited in claim 39, wherein said pH-control layer is comprised of a material capable of precluding electrolysis in the reservoir, when an electrical potential is imposed between said backing layer and the skin of a patient with the medicament patch disposed there against.

43. An active electrode as recited in claim 39, wherein said pH-control layer is comprised of a material capable of neutralizing electrolysis products in the reservoir, when an electrical potential is imposed between said backing layer and the skin of a patient with the medicament patch disposed there against.

44. An active electrode as recited in claim 39, wherein the area of said pH-control layer is less than the area of said driving face of said backing layer.

45. An active electrode as recited in claim 39, wherein the area of said pH-control layer is equal to the area of said driving face of said backing layer.

46. An active electrode as recited in claim 39, wherein the ratio of the area of said driving face of said backing layer to the area of said pH-control layer is in a range from about 0.15 to about 1.00.