METHODS AND ARCHITECTURE FOR POWER OPTIMIZATION OF IONTOPHORETIC TRANSDERMAL DRUG DELIVERY

• US 20110196283A1
• Filed: 02/09/2011
• Published: 08/11/2011
• Est. Priority Date: 02/10/2010
• Status: Active Grant

• Current Assignee: InCube Labs LLC. (In-Cube, Inc.)
• Original Assignee: InCube Labs LLC. (In-Cube, Inc.)
• Inventors: Mangogna, George Andrew, Malhotra, Vikram, Andersen, Dean P., Imran, Mir
• Granted Patent: US 8,986,279 B2
• Time in Patent Office: Days
• US Class Current: 604/20
• CPC Class Codes: A61N 1/044 Shape of the electrode
• CPC Class Codes: A61N 1/0448 Drug reservoir
• CPC Class Codes: A61N 1/303 Constructional details electrodes for external use A61N1/0428
• CPC Class Codes: A61N 1/325 for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body electrodes for external use A61N1/0428
• CPC Class Codes: A61P 3/00 Drugs for disorders of the metabolism of the blood or the extracellular fluid A61P7/00
• CPC Class Codes: A61P 3/10 for hyperglycaemia, e.g. antidiabetics

Abstract

Embodiments of the invention provide an architecture, system and methods for optimizing power utilization for transdermal iontophoretic drug delivery which maintain a iontophoretic driving voltage at a reduced or even minimum value to support an iontophoretic delivery current. The reduced voltage reduces the power requirements for a transdermal iontohoretic delivery system during a period of drug delivery. Embodiments of an architecture for implementing this approach can utilize a controller which compares the desired current to the actual current and adjusts the voltage to reduce the amount of power used for iontophoretic drug delivery. The controller can comprise a state machine or microprocessor. Embodiments of the invention are particularly useful for extending the battery life of transdermal iontophoretic drug delivery systems.

Claims

1. A method for optimizing power for the iontophoretic transdermal delivery of a therapeutic agent to a patient in need thereof, the method comprising:

applying a patch to the skin of the patient, the patch comprising a therapeutic agent and at least one electrode;

coupling the at least one electrode to a power source;

delivering a selected current to the skin from the patch to transport the therapeutic agent into the skin;

measuring an electrical property of a circuit comprising the patient and the power source; and

adjusting a voltage responsive to the measured electrical property, wherein the voltage is adjusted to maintain the selected current while minimizing power delivered from the power source.

2. The method of claim 1, wherein power from the power source is reduced by up to about 45 percent by adjustment of the voltage.

3. The method of claim 1, wherein power from the power source is reduced by up to about 60 percent by adjustment of the voltage.

4. The method of claim 1, wherein the therapeutic agent comprises an iron containing compound for the treatment of iron deficiency anemia.

5. The method of claim 1, wherein the therapeutic agent comprises insulin or a glucagon like peptide for the treatment of a blood sugar regulation disorder.

6. The method of claim 1, wherein the therapeutic agent comprises Fentanyl or an opioid for pain management.

7. The method of claim 1, wherein the electrical property is one of a skin impedance, a skin resistance, a lumped impedance, a lumped resistance or a delivered current.

8. The method of claim 1, wherein the power source is an electrochemical battery and battery life is extended by adjustment of the voltage.

9. The method of claim 8, wherein the battery is a lithium or alkaline battery.

10. The method of claim 8, wherein a battery voltage or current is maintained above a minimum level for a therapeutic agent delivery period as a result of the minimized delivered power.

11. The method of claim 10, wherein the delivery period is up to about one week.

12. The method of claim 10, wherein the delivery period is up to about two weeks.

13. The method of claim 1, wherein the current is an alternating current.

14. The method of claim 8, wherein the current has a frequency in a range from about 0.5 to 100 hz.

15. The method of claim 1, wherein the electrical property is measured over a range of frequencies.

16. The method of claim 10, wherein the range of frequencies is from about 0.01 to about 1000 hz.

17. The method of claim 1, wherein the voltage is adjusted using a controller.

18. The method of claim 17, wherein the controller is an analog device, a state machine, a digital controller or a microprocessor.

19. The method of claim 17, wherein the controller utilizes a software module to adjust the voltage.

20. The method of claim 1, wherein the electrical property is measured using a sensor.

21. The method of claim 20, wherein the sensor is coupled to at least one of the power source or a controller coupled to the power source.

22. The method of claim 20, wherein the sensor is positioned on or in the patch.

23. The method of claim 20, wherein the sensor comprises the at least one electrode.

24. The method of claim 1, wherein the electrical property is measured in a substantially continuous fashion during the period current is delivered to the skin.

25. The method of claim 1, wherein the electrical property is measured at fixed intervals during the period current is delivered to the skin.

26. The method of claim 25, wherein an interval duration is in a range of about 0.001 to 1 seconds.

27. The method of claim 25, wherein a period between intervals is in a range of about 0.001 to 1 second.

28. A method for optimizing power for the iontophoretic transdermal delivery of a therapeutic agent to a patient in need thereof, the method comprising:

applying a patch to the skin of the patient, the patch comprising a therapeutic agent and at least one electrode;

coupling the at least one electrode to a power source;

delivering a selected current to the skin from the patch to transport the therapeutic agent into the skin;

measuring an electrical impedance of the patient; and

adjusting a voltage responsive to the measured impedance, wherein the voltage is adjusted to maintain the selected current while minimizing power delivered from the power source.

29. The method of claim 28, wherein the impedance is measured in a volume of tissue between the at least one electrode and a return electrode applied to the skin of the patient.

30. The method of claim 28, wherein the impedance is measured in a circuit comprising at least two of the at the least one electrode, the patient'"'"'s tissue and the power source.

31. A architecture for optimizing power for the iontophoretic transdermal delivery of a therapeutic agent to a patient in need thereof, the architecture comprising:

a first and second electrode, at least one of the electrodes operably coupled to a iontphoretic transdermal patch for delivering the therapeutic agent to the patient;

a power source operably coupled with the first and second electrodes, the power source comprising a voltage source and a voltage converter operably coupled to the voltage source;

a current source operably coupled to at least one of the first and second electrodes;

a measurement device operably coupled to the current source; and

a controller operably coupled to the measurement device and the voltage regulator, the controller including logic for utilizing an input from the measurement device to generate an output sent to the voltage regulator so as to maintain current from the current source above a threshold level while minimizing power drawn from the power source.

32. The architecture of claim 31, wherein the measurement device is one of an impedance measurement device or a current measurement device.

33. The architecture of claim 31, wherein the controller is a microprocessor.

34. The architecture of claim 33, wherein the controller logic is incorporated into a software module operable by the controller.

35. The architecture of claim 31, wherein the voltage source is one of an electrochemical storage battery, a lithium battery or an alkaline battery.

36. The architecture of claim 31, wherein at least two components of the architecture are fabricated on a single integrated circuit.

37. The architecture of claim 36, wherein the integrated circuit is an ASIC.

38. The architecture of claim 31, wherein the controller logic is configured to generate an output sent to the current source for controlling current from the current source.

39. The architecture of claim 31, wherein the measurement devices comprises a resistor and an op-amp.

40. The architecture of claim 39, wherein the measurement devices further comprises an A/D converter.