Claims for Patent: 5,004,610

Summary for Patent: 5,004,610

Title:	Subsaturated nicotine transdermal therapeutic system
Abstract:	Rate controlled transdermal nicotine delivery systems are disclosed which utilize an in-line adhesive to maintain the systems on the skin. The initial equilibrated concentration of nicotine in the nicotine reservoir and the adhesive is below saturation, preferably at a thermodynamic activity no greater than 0.50, and the reservoir comprises the nicotine dissolved in a material with respect to which the rate controlling element of the device is substantially impermeable. In preferred embodiments the initial loading of nicotine in the reservoir is sufficient to prevent the activity of the nicotine in the reservoir from decreasing by more than about 75% and preferably no more than about 25% during the predetermined period of administration; and the thickness of the adhesive, rate controlling membrane and reservoir layers are selected so that at least 50% and, preferably at least 75% of the initial equilibrated nicotine loading is in the reservoir layer.
Inventor(s):	Osborne; James L. (Mountain View, CA), Nelson; Melinda (Sunnyvale, CA), Enscore; David J. (Saratoga, CA), Yum; Su I. (Los Altos, CA), Gale; Robert M. (Los Altos, CA)
Assignee:	ALZA Corporation (Palo Alto, CA)
Application Number:	07/537,672
Patent Claims:	1. A medical device for the transdermal administration of nicotine, said device being adapted to deliver nicotine during a predetermined nicotine administration period of at least about eight hours at a rate within the range of about 250-4000 .mu.g/hr for a substantial portion of said administration period, said device comprising, in combination: a. nicotine reservoir comprising said nicotine dissolved in a solvent at a concentration less than saturation and at an initial equilibrated nicotine loading sufficient to prevent the concentration of nicotine in said solvent from decreasing by more than 75% during said administration period; b. nicotine release rate controlling means disposed in the path of nicotine migration from said reservoir to the skin, said rate controlling means being permeable to nicotine and substantially impermeable to said solvent; c. adhesive means disposed in the path of nicotine migration from said release rate controlling means to the skin; and d. removable release liner means on said adhesive. 2. The device of claim 1 wherein the initial equalibrated thermodynamic activity of nicotine is no greater than about 0.50. 3. The device of claim 2 wherein said adhesive has a high nicotine solubility. 4. The device of claim 2 wherein at least 50% of the initial loading of the nicotine in the device is in the nicotine reservoir. 5. The device of claim 2 wherein said decrease in activity is no greater than about 25%. 6. The device of claim 5, wherein at least 75% of the initial nicotine loading is in the reservoir. 7. The device of claim 2 wherein said rate controlling means is substantially impermeable to the passage of the reservoir solvent. 8. The device of claim 1 wherein the initial equilibrated thermodynamic activity of nicotine in said reservoir and adhesive layers is in the range of about 0.20-0.40. 9. A medical device for the transdermal administration of nicotine utilizing an in-line adhesive, said device being adapted to deliver nicotine at a rate within the range of about 250-4000 .mu.g/hr during a substantial portion of a predetermined administration period of at least about 8 hours comprising, in combination: a. a nicotine reservoir comprising nicotine dissolved in an ethylene vinyl acetate copolymer at a concentration less than saturation and at an initial equilibrated nicotine loading sufficient to prevent the thermodynamic activity of nicotine in said ethylene vinyl acetate copolymer from decreasing by more than 75% during said administration period; b. nicotine release rate controlling means disposed in the path of nicotine migration from said reservoir to the skin said rate controlling means being permeable to nicotine and substantially impermeable to said solvent and being selected form the group consisting of low density polyethylene, high density polyethylene and ethylene vinyl acetate copolymers; c. adhesive means disposed in the path of nicotine migration from said release rate controlling means to the skin; and d. removable release liner means on said adhesive. 10. The device of claim 9 wherein the initial equilibrated thermodynamic activity of nicotine is no greater than about 0.50. 11. The device of claim 10 wherein the thickness of said reservoir, rate-controlling and adhesive means are selected such that at least 50% of the initial equilibrated loading of nicotine is in the reservoir. 12. The device of claim 10 wherein the thickness of said reservoir, rate-controlling and adhesive means are selected such that at least 75% of the initial equilibrated loading of nicotine is in the reservoir. 13. The device of claim 11 wherein the initial equilibrated loading of nicotine in said reservoir is sufficient to prevent the thermodynamic activity of said nicotine in said solvent from decreasing by more than 25% during said administration period. 14. The device of claim 12 wherein the initial equilibrated loading of nicotine in said reservoir is sufficient to prevent the thermodynamic activity of said nicotine in said solvent from decreasing by more than 25% during said administration period. 15. The device of claim 9 wherein the initial equilibrated thermodynamic activity of nicotine in said reservoir and adhesive layers is in the range of about 0.20-0.40. 16. The device of claim 14 wherein the initial equilibrated thermodynamic activity of nicotine in said reservoir and adhesive layers is in the range of about 0.20-0.40. 17. The device of claim 16 wherein said ethylene vinyl acetate reservoir copolymer has a vinyl acetate content of about 40%. 18. A medical device for the transdermal administration of nicotine, said device comprising, in combination: a. a subsaturated nicotine reservoir comprising 5 to 40 wt % nicotine and 60 to 95 wt % ethylene vinyl acetate copolymer having a vinyl acetate contact in the range of about 28-40%, said reservoir containing sufficient nicotine to administer nicotine at a rate within the range of about 250 to 4000 .mu.g/hr during a substantial portion of an administration period of at least about 8 hours while preventing the activity of said nicotine from decreasing by more than 75% during said administration period; b. nicotine release rate controlling means disposed in the path of nicotine migration from said reservoir to the skin, said rate controlling means being a high density polyethylene membrane; c. adhesive means disposed in the path of nicotine migration from said release rate controlling means to the skin: and d. removable release liner means on said adhesive. 19. The device of claim 18 wherein said nicotine loading is about 5 mg/cm.sup.2. 20. The device of claim 18 wherein the thickness of said reservoir, rate-controlling and adhesive means is selected such that at least 50% of the initial equilibrated nicotine loading is in the reservoir. 21. The device of claim 18 wherein said administration period is about 24 hours. 22. The device of claim 2 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 23. The device of claim 6 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 24. The device of claim 8 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 25. The device of claim 10 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 26. The device of claim 15 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 27. The device of claim 16 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 28. The device of claim 18 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr. 29. The device of claim 20 wherein the steady state flux is in the range of about 30-120 .mu.g/cm.sup.2 hr.