Claims for Patent: 4,725,439

Summary for Patent: 4,725,439

Title:	Transdermal drug delivery device
Abstract:	A medical device for the transdermal delivery of an active agent through sensitive intact skin is provided. The device comprises a matrix containing the drug having reinforcing means, preferably in the form of a fabric, embedded in the upper surface of the matrix. The matrix is formed of an agent permeable material which is tacky but does not adhesively bond to the skin. The device is sufficiently flexible and deformable that the combination of tackiness, flexibility, and deformation permits the device to be maintained in agent transmitting relationship upon skin at such sensitive areas as the scrotum, labia, breast, or penis, for example. In certain embodiments, the skin distal surface is provided with a layer of an agent impermeable material to reduce transfer of the agent from the patient to others.
Inventor(s):	Campbell; Patricia S. (Palo Alto, CA), Eckenhoff; James B. (Los Altos, CA), Place; Virgil A. (Kawaihae, HI)
Assignee:	ALZA Corporation (Palo Alto, CA)
Application Number:	06/818,561
Patent Claims:	1. A flexible and compliant medical device for the transdermal administration of a biological agent through intact skin at sensitive body locations comprising, in combination: (a) an agent reservoir comprising said agent dispersed through a non-aqueous, nonadhesive polymeric carrier permeable to said agent, said reservoir having a body contacting surface through which said agent is released to the skin and a body distal surface opposite said body contacting surface, the body contacting surface of said reservoir having a tack in the range of about 50-500 g/cm.sup.2 at 35.degree. C.; (b) a flexible bonding agent substantially less permeable to said agent than the polymeric carrier forming said reservoir, said bonding agent coating substantially all of said body distal surface of said reservoir; and (c) fibrous reinforcing means imbedded in said bonding means to a depth that does not penetrate through said body contacting surface and does not submerge said reinforcing means in said bonding means, said imbedded fibrous reinforcing means forming the body distal surface of said device; whereby said bonding agent bonds said fibrous reinforcing means to said reservoir, substantially impedes the transfer of said agent from the body distal surface of said device to other surfaces and the body distal surface of said device retains a fibrous texture. 2. The device of claim 1 wherein said agent is selected from the group consisting of testosterone, progesterone, estradiol, acyclovir, interferon, cortisone and phenolphthalein, cyproterone, LHRH, their active metabolites, and their prodrugs. 3. A method of transdermal administration of an agent which comprises applying a device according to claim 1 to a body site selected from the group consisting of the scrotum, the labia, the penis or the breast, and maintaining said system in place for an extended period of time. 4. The device of claim 1 further comprising a removable agent impermeable liner disposed on the body contacting surface to protect the device in storage. 5. The device of claim 1 wherein said reinforcing means comprises a fabric web which is non-elastically deformable in at least one direction. 6. The device of claim 5 wherein said fabric is anisotropically deformable. 7. The device of claim 5 wherein said fabric is isotropically deformable. 8. The device of claim 1 wherein said reinforcing means comprises a spun-bonded fabric. 9. The device of claim 1 wherein said carrier is an ethylene/vinyl acetate copolymer having a vinyl acetate content of about 28-61%. 10. The device of claim 9 wherein said vinyl acetate content is in the range of about 40-60%. 11. The device of claim 1 wherein said agent is dispersed within said carrier at a concentration less than saturation. 12. The device of claim 1 wherein said device has a thickness of about 2-10 mils. 13. The device of claim 1 wherein said bonding material is polyisobutylene. 14. The device of claim 1 wherein said device has an extension modulus at 15% elongation in at least one dimension in the range of 1000 to 15,000 gm/cm.sup.2. 15. The device of claim 14 wherein said device has a stress decay from 15% elongation after 5 minutes in the range of 25-45%. 16. The device of claim 15 wherein a 2 cm wide strip required an elongation force of 30-300 gm to produce a 15% elongation. 17. The device of claim 16 wherein said modulus is in the range of about 1000-5000 gm/cm.sup.2, said elongation force is in the range of about 50-150 gm. 18. A flexible and compliant medical device particularly adapted for the transdermal administration of a biological agent through the skin of the human genitalia, said device having an extension modulus at 15% elongation in at least one direction in the range of 1000 to 15,000 gm/cm.sup.2, a stress decay from 15% elongation at 5 minutes in the range of 25-45%, a 2 cm wide strip of said device requiring an elongation force of from 30-300 gm to produce said 15% elongation, said device comprising, in combination: (a) an agent reservoir comprising said agent dispersed through a non-aqueous, nonadhesive polymeric carrier permeable to said agent, said reservoir having a body contacting surface through which said agent is released to the skin and a body distal surface opposite said body contacting surface, the body contacting surface of said reservoir having a tack in the range of about 50-500 g/cm.sup.2 at 35.degree. C.; (b) a flexible bonding agent substantially less permeable to said agent than the polymeric carrier forming said reservoir, said bonding agent coating substantially all of said body distal surface of said reservoir; and (c) fibrous reinforcing means imbedded in said bonding means to a depth that does not penetrate through said body contacting surface and does not submerge said reinforcing means in said bonding means, said imbedded fibrous reinforcing means forming the body distal surface of said device; said fibrous reinforcing means being being non-elastically deformable in at least one direction; whereby said bonding agent bonds said fibrous reinforcing means to said reservoir, substantially impedes the transfer of said agent from the body distal surface of said device to another surface, the body distal surface of said device retains a fibrous texture and said device will be capable of clinging to irregular skin surfaces after application thereto. 19. The device of claim 18 wherein said agent is selected from the group consisting of testosterone, progesterone, estradiol, acyclovir, interferon, cortisone, phenolphthalein, cyproterone, LHRH, their active metabolites and their prodrugs. 20. The device of claim 18 wherein said device is from 2-10 mils thick. 21. The device of claim 18 wherein said reservoir comprises an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of about 28-61%. 22. A flexible and compliant medical device for the transdermal administration of testosterone through the skin of the human male genitalia, said device being from 2-10 mils thick and having an extension modulus at 15% elongation in at least one direction in the range of 1000 to 15,000 gm/cm.sup.2, a stress decay from 15% elongation at 5 minutes in the range of 25-45%, a 2 cm wide strip of said device requiring an elongation force of from 30-300 gm to produce said 15% elongation, said device comprising, in combination: (a) a testosterone reservoir comprising testosterone dissolved in a non-aqueous, nonadhesive polymeric carrier permeable to said testosterone, said reservoir having a body contacting surface through which testosterone is released to the skin and a body distal surface opposite said body contacting surface, the body contacting surface of said reservoir having a tack in the range of about 50-500 g/cm.sup.2 at 35.degree. C.; (b) a flexible bonding agent substantially less permeable to testosterone than the polymeric carrier forming said reservoir, said bonding agent coating substantially all of said body distal surface of said reservoir; and (c) fibrous reinforcing means imbedded in said bonding means to a depth that does not penetrate through said body contacting surface and does not submerge said reinforcing means in said bonding means, said imbedded fibrous reinforcing means forming the body distal surface of said device; said fibrous reinforcing means being being non-elastically deformable in at least one direction; whereby said bonding agent bonds said fibrous reinforcing means to said reservoir, substantially impedes the transfer of testosterone from the body distal surface of said device to another surface, the body distal surface of said device retains a fibrous texture and said device is capable of non-adhesively clinging to the skin of the male genitalia in testosterone transmitting relationship thereto. 23. The device of claim 22 wherein said reservoir comprises an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of about 28-61%. 24. The device of claim 23 wherein said reservoir comprises an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of about 40-60%. 25. The device of claim 22 wherein said reinforcing means is isotropically non-elastically deformable. 26. A method of testosterone replacement in hypogonadal males which comprises applying a device according to claim 22 to the genitalia of a hypogonadal male and maintaining said device in testosterone transmitting relationship thereto for at least about 8 hours. 27. The method of claim 26 wherein said device is replaced with a fresh device on a daily basis. 28. The device of claim 24 wherein said device is free of undissolved testosterone and contains testosterone at a loading of from about 5-15 mg. 29. The device of claim 23 wherein said bonding agent comprises a polyisobutylene polymer. 30. The device of claim 23 wherein said bonding agent comprises a polyisobutylene polymer. 31. A method for testosterone replacement in hypogonadic males which comprises applying the device of claim 22 to the scrotum of a hypogonadic male and maintaining said system in testosterone transferring relationship to said scrotum for at least about 8 hours. 32. The method of claim 31 wherein said system is maintained in place for up to about 24 hours and is replaced with a freshsystem after removal whereby continuous testosterone replacement is obtained. 33. The method of claim 31 wherein said device is stretched in application to the scrotum whereby the device conforms to and clings to the scrotal skin. 34. The device of claim 9 wherein said bonding agent comprises a polyisobutylene polymer. 35. The device of claim 21 wherein said bonding agent comprises a polyisobutylene polymer. 36. The device of claim 23 wherein said bonding agent comprises a polyisobutylene polymer. 37. The device of claim 10 wherein said bonding agent comprises a polyisobutylene polymer. 38. The device of claim 24 wherein said bonding agent comprises a polyisobutylene polymer. 39. The device of claim 1 wherein said tack is in the range of 100-300 g/cm.sup.2 at 35.degree. C. 40. The device of claim 18 wherein said tack is in the range of 100-300 g/cm.sup.2 at 35.degree. C. 41. The device of claim 22 wherein said tack is in the range of 100-300 g/cm.sup.2 at 35.degree. C. 42. The device of claim 21 wherein said fibrous reinforcing means is a polyester fabric. 43. The device of claim 18 wherein said fibrous reinforcing means is a polyester fabric. 44. A flexible and compliant medical device particularly adapted for the transdermal administration of a biological agent through intact skin at sensitive body locations said device being from 2-10 mils thick and having an extension modulus at 15% elongation in at least one direction in the range of 1000 to 15,000 gm/cm.sup.2, a stress decay from 15% elongation at 5 minutes in the range of 25-45%, a 2 cm wide strip of said device requiring an elongation force of from 30-300 gm to produce said 15% elongation, said device comprising, in combination: (a) an agent reservoir comprising said agent dispersed through a non-aqueous, nonadhesive polymeric carrier permeable to said agent, said reservoir having a body contacting surface through which agent is released to the skin and a body distal surface opposite said body contacting surface, the body contacting surface of said reservoir having a tack in the range of about 50-500 g/cm.sup.2 at 35.degree. C.; (b) fibrous reinforcing means imbedded in said reservoir to a depth that does not penetrate through said body contacting surface and does not submerge said reinforcing means in said reservoir, said imbedded fibrous reinforcing means forming the body distal surface of said device; said fibrous reinforcing means being being non-elastically deformable in at least one direction; whereby the body distal surface of said device retains a fibrous texture and said device is capable of non-adhesively clinging to the skin at sensitive body locations in agent transmitting relationship thereto. 45. The device of claim 44 wherein said reservoir comprises an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of about 40-60%. 46. The device of claim 45 wherein said reinforcing means comprises a polyester fabric. 47. A method of testosterone replacement in hypogonadal males which comprises applying a device according to claim 44 in which said agent is testosterone to the genitalia of a hypogonadal male and maintaining said device in testosterone transmitting relationship thereto for at least about 8 hours. 48. The method of claim 47 wherein said device is replaced with a fresh device on a daily basis. 49. The device of claim 45 wherein said agent is testosterone, said device is free of undissolved testosterone and contains testosterone at a loading of from about 5-15 mg. 50. A method for testosterone replacement in hypogonadic males which comprises applying the device of claim 44 in which said agent is testosterone to the scrotum of a hypogonadic male and maintaining said system in testosterone transferring relationship to said scrotum for at least about 8 hours. 51. The method of claim 50 wherein said system is maintained in place for up to about 24 hours and is replaced with a fresh system after removal whereby continuous testosterone replacement is obtained. 52. The method of claim 50 wherein said device is stretched in application to the scrotum whereby the device conforms to and clings to the scrotal skin. 53. The device of claim 44 wherein said tack is in the range of 100-300 g/cm.sup.2 at 35.degree. C. 54. The device of claim 46 wherein said tack is in the range of 100-300 g/cm.sup.2 at 35.degree. C.