Claims for Patent: 5,232,438

Summary for Patent: 5,232,438

Title:	Membrane for electrotransport transdermal drug delivery
Abstract:	A membrane capable of inhibiting agent release from a delivery system when no electrical current is flowing and yet provide minimal impedance to electrically-assisted agent delivery, useful both for incorporating into electrotransport agent delivery systems and for use in measuring agent release rates in in vitro testing.
Inventor(s):	Theeuwes; Felix (Los Altos, CA), Gyory; J. Richard (Los Altos, CA), Haak; Ronald P. (Cupertino, CA)
Assignee:	Alza Corporation (Palo Alto, CA)
Application Number:	07/898,618
Patent Claims:	1. An iontophoretic agent delivery electrode assembly adapted for placement on a body surface for iontophoretic delivery of an analgesic drug therethrough, the electrode assembly including an electrode, a means for connecting said electrode to a source of electrical power, and a drug reservoir electrically connected to the electrode, the drug reservoir containing an analgesic drug in a form susceptible to iontophoretic delivery through the body surface, the drug being selected from the group consisting of fentanyl, sufentanil, analogues of fentanyl, analogues of sufentanil and pharmaceutically acceptable salts thereof. 2. The electrode assembly of claim 1, wherein the analgesic drug comprises a water soluble fentanyl salt. 3. The electrode assembly of claim 1, wherein the analgesic drug comprises a water soluble sufentanil salt. 4. The electrode assembly of claim 1, wherein the source of electrical power provides a current density of about 50 to 625 .mu.A/cm.sup.2. 5. The electrode assembly of claim 1, wherein the source of electrical power provides a current density of about 100 .mu.A/cm.sup.2. 6. The electrode assembly of claim 1, wherein the drug comprises fentanyl or a pharmaceutically acceptable analogue of fentanyl of a salt thereof. 7. The electrode assembly of claim 1, wherein the drug comprises sufentanil or a pharmaceutically acceptable analogue of sufentanil or a salt thereof. 8. An electrically powered iontophoretic delivery device including a donor electrode assembly adapted to be placed in drug transmitting relation with a body surface, a counter electrode assembly adapted to be placed in agent transmitting relation with a body surface and a source of electrical power adapted to be electrically connected to the donor electrode assembly and the counter electrode assembly, wherein the donor electrode assembly contains an ionized or ionizable source of an analgesic drug selected from the group consisting of fentanyl, sufentanil, analogues of fentanyl, analogues of sufentanil and pharmaceutically acceptable salts thereof. 9. The device of claim 8, wherein the drug comprises fentanyl or a pharmaceutically acceptable analogue of fentanyl or a salt thereof. 10. The device of claim 8, wherein the drug comprises sufentanil or a pharmaceutically acceptable analogue of sufentanil or a salt thereof. 11. The device of claim 8, wherein the source of electrical power provides a current density of about 50 to 625 .mu.A/cm.sup.2. 12. The device of claim 8, wherein the source of electrical power provides a current density of about 100 .mu.A/cm.sup.2. 13. A method of inducing analgesia, comprising: placing an electrotransport agent delivery electrode assembly on a body surface, the electrode assembly including a drug reservoir and a means for electrically connecting said drug reservoir to a source of electrical power, the drug reservoir containing an analgesic drug in a form susceptible to electrotransport delivery through the body surface, the drug being selected from the group consisting of fentanyl, sufentanil, analogues of fentanyl, analogues of sufentanil and pharmaceutically acceptable salts thereof; electrically connecting the drug reservoir to the source of electrical power; placing the drug reservoir in drug-transmitting relation with the body surface; and delivering the analgesic drug through the body surface by means of electrotransport, the drug being delivered at a rate sufficient to induce analgesia. 14. The method of claim 13, wherein the analgesic drug comprises a water soluble fentanyl salt. 15. The method of claim 13, wherein the analgesic drug comprises a water soluble sufentanil salt. 16. The method of claim 13, wherein the source of electrical power provides a current density of about 50 to 625 .mu.A/cm.sup.2. 17. The method of claim 13, wherein the source of electrical power provides a current density of about 100 .mu.A/cm.sup.2. 18. The method of claim 13, wherein the drug comprises fentanyl or a pharmaceutically acceptable analogue of fentanyl or a salt thereof. 19. The method of claim 13, wherein the drug comprises sufentanil or a pharmaceutically acceptable analogue of sufentanil or a salt thereof. 20. A method of inducing analgesia in a human patient, comprising: placing in drug transmitting relation with a body surface of the patient an electrically powered iontophoretic delivery device, the delivery device including a donor electrode assembly and a counter electrode assembly, the donor electrode assembly containing an ionized or ionizable source of an analgesic drug selected from the group consisting of fentanyl, sufentanil, analogues of fentanyl, analogues of sufentanil and pharmaceutically acceptable salts thereof; placing the counter electrode assembly in ion transmitting relation with the body surface at a location spaced apart from the donor electrode assembly; electrically connecting a source of electrical power to the donor electrode assembly and the counter electrode assembly; and iontophoretically delivering the analgesic drug through the body surface at a rate sufficient to induce analgesia in the patient. 21. The method of claim 20, wherein the drug comprises fentanyl or a pharmaceutically acceptable analogue of fentanyl or a salt thereof. 22. The method of claim 20, wherein the drug comprises sufentanil or a pharmaceutically acceptable analogue of sufentanil or a salt thereof. 23. The method of claim 20, wherein the source of electrical power provides a current density of about 550 to 625 .mu.A/cm.sup.2. 24. The method of claim 20, wherein the source of electrical power provides a current density of about 100 .mu.A/cm.sup.2.