Drug delivery apparatus

• US 20060030837A1
• Filed: 01/28/2005
• Published: 02/09/2006
• Est. Priority Date: 01/29/2004
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated, Massachusetts Eye And Ear Infirmary (Foundation of The Massachusetts Eye and EAR Infirmary Incorporated)
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Kujawa, Sharon G., Fiering, Jason O., Mescher, Mark J., McKenna, Michael J., Sewell, William F., Mikulec, Anthony A.
• Granted Patent: US 7,867,193 B2
• Time in Patent Office: Days
• US Class Current: 604/890.100
• CPC Class Codes: A61F 11/00 Methods or devices for treatment of the ears or hearing sense implantable prostheses that substitute or replace internal ear parts, e.g. ear-drums, A61F2/18; methods or devices to cause a change in the state of auditory consciousness A61M21/00; electrotherapy applying electrical stimulation of the auditory system, or circuits therefor A61N1/36; radiotherapy using optical stimulation of the auditory system A61N5/06; electro-acoustic hearing aids H04R25/00; Non-electric hearing aids; Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense; Protective devices for the ears, carried on the body or in the hand headwear, e.g. caps or helmets, with means for protecting the ears A42B1/0188, A42B3/16
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 2205/3379 Masses, volumes, levels of fluids in reservoirs, flow rates
• CPC Class Codes: A61M 2210/0662 Ears
• CPC Class Codes: A61M 2210/0668 Middle ear
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61M 5/14224 Diaphragm type
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

An implantable drug delivery apparatus for delivering a drug into a bodily fluid in a body cavity of a patient over a period of time, which includes a hollow member that defines at least one lumen for facilitating a unidirectional recirculating flow of a therapeutic fluid through the lumen. The fluid can contain a bodily fluid, such as, for example, perilymph, and a drug. The apparatus also includes a pump, for example a single unidirectional pump, to control the flow rate of the therapeutic fluid through the hollow member, and an interface member in communication with at least one lumen of the hollow member. The device thus allows for the controlled delivery of the therapeutic fluid to a predetermined location in the bodily cavity of the patient, such as, for example, a cochlea of a human ear.

Claims

1. A drug delivery apparatus for delivering a drug into a bodily fluid in a bodily cavity of a patient over a period of time, the apparatus comprising:

a hollow member defining at least one lumen for facilitating a unidirectional recirculating flow of a therapeutic fluid therethrough, the therapeutic fluid comprising a first volume of the bodily fluid and the drug contained therein;

a pump for controlling a flow rate of the therapeutic fluid through the hollow member; and

an interface member in fluid communication with the at least one lumen of the hollow member for delivering at least a portion of the therapeutic fluid to a predetermined location in the bodily cavity.

2. The apparatus of claim 1 wherein the interface member is in fluid communication with the bodily fluid in the bodily cavity.

3. The apparatus of claim 1 wherein the interface member periodically draws a second volume of the bodily fluid from the bodily cavity.

4. The apparatus of claim 1 wherein the interface member is in fluid communication with a cochlea of a human ear.

5. The apparatus of claim 1 wherein the bodily fluid comprises human perilymph.

6. The apparatus of claim 1 wherein the hollow member comprises a closed loop of tubing or at least one elongated member defining at least one sealed channel.

7. The apparatus of claim 6 wherein the loop of tubing comprises a double-lumen catheter.

8. The apparatus of claim 1 wherein the fluid capacitance and fluid resistance of at least one of the hollow member and the interface member are selected to obtain an oscillating flow of the therapeutic fluid through the interface member.

9. The apparatus of claim 1 wherein the interface member comprises a cannula.

10. The apparatus of claim 1 wherein the drug is dissolved in the first volume of the bodily fluid.

11. The apparatus of claim 1 wherein concentration of the drug in the therapeutic fluid varies during recirculation thereof through the hollow member.

12. The apparatus of claim 1, further comprising a reservoir member for storing the drug, the reservoir member defining a first chamber in communication with the at least one lumen of the hollow member.

13. The apparatus of claim 12 wherein the reservoir member defines a second chamber in communication with the first chamber for controllably mixing the drug with the bodily fluid.

14. The apparatus of claim 12 further comprising a regulating system for maintaining an optimal drug delivery rate, the regulating system being in communication with at least one the pump and the reservoir.

15. The apparatus of claim 14 wherein the regulating system comprises a sensor for periodically measuring concentration of drug in the therapeutic fluid and transmitting the measured value of the concentration to the regulating system.

16. The apparatus of claim 14 wherein the regulating system comprises a sensor for periodically measuring concentration of drug in the bodily fluid and transmitting the measured value of the concentration to the regulating system.

17. The apparatus of claim 1 wherein the pump comprises a microelectromechanical microfluidic pump operating at a predetermined frequency.

18. The apparatus of claim 17 wherein the frequency of the pump is substantially constant.

19. The apparatus of claim 17 wherein the frequency of the pump is modulated.

20. The apparatus of claim 1 wherein the pump causes the therapeutic fluid to flow through the hollow member at the flow rate of less than about one microliter per minute.

21. The apparatus of claim 1 further comprising a control system in electric communication with the pump for controlling a flow pattern of the therapeutic fluid through the hollow member.

22. The apparatus of claim 18 wherein the control system comprises a receiver for receiving electric signals from a remote device.

23. The apparatus of claim 18 wherein the control system comprises a transmitter for transmitting electric signals to a remote device.

24. The apparatus of claim 18 wherein the control system comprises a memory element.

25. The apparatus of claim 18 further comprising at least one sensor in communication with the control system for detecting and transmitting data to the control system.

26. The apparatus of claim 25 wherein data is selected from the group consisting of:

at least one flow pattern parameter of the therapeutic fluid, concentration of the drug in the therapeutic fluid, and concentration of the drug in the bodily fluid.

27. The apparatus of claim 1 wherein the at least one of the pump and the hollow member is shaped and dimensioned to fit within a mastoid cavity of a human.

28. An implantable drug delivery apparatus for delivering a drug into a bodily fluid in a bodily cavity of a patient over a period of time, the apparatus comprising:

a hollow member defining at least one lumen for facilitating a flow of a therapeutic fluid therethrough, the therapeutic fluid comprising the drug;

a pump for controlling a flow rate of the therapeutic fluid through the hollow member; and

an interface member in fluid communication with the at least one lumen of the hollow member and the bodily fluid in the inner ear cavity for delivering at least a portion of the therapeutic fluid into the bodily fluid in a predetermined location in the bodily cavity.

29. The apparatus of claim 28 wherein the at least one of the pump and the hollow member is shaped and dimensioned to fit within a mastoid cavity of a human.

30. The apparatus of claim 28 wherein the therapeutic fluid comprises human perilymph.

31. A method for delivering a drug into a bodily fluid in a bodily cavity of a patient over a period of time, the method comprising the steps of:

drawing a first volume of the bodily fluid from the patient'"'"'s bodily cavity;

mixing the drug with the bodily fluid thereby obtaining a therapeutic fluid; and

releasing a first volume of the therapeutic fluid into the bodily cavity.

32. The method of claim 31, further comprising providing a hollow member defining at least one lumen in communication with the bodily cavity and causing a unidirectional flow of the bodily fluid through the hollow member.

33. The method of claim 32, further comprising controllably recirculating the therapeutic fluid through the hollow member.

34. The method of claim 33, further comprising an interface member in fluid communication with the at least one lumen of the hollow member for delivering at least a portion of the therapeutic fluid to a predetermined location in the bodily cavity, the hollow member and the interface member being characterized by flow capacitance and flow resistance selected to obtain an oscillating flow of the therapeutic fluid through the interface member.

35. The method of claim 32, further comprising altering concentration of the drug in the therapeutic fluid during recirculation thereof through the hollow member.

36. The method of claim 35 wherein the flow rate of the therapeutic fluid during recirculation through the hollow member is substantially constant.

37. The method of claim 31, further comprising drawing a second volume of the bodily fluid from the bodily cavity.

38. The method of claim 31 wherein the therapeutic fluid comprises a solution of the drug in the bodily fluid.

39. The method of claim 31 wherein the bodily cavity is a human cochlea and the bodily fluid comprises human perilymph.

40. The method of claim 39 further comprising controllably altering fluid pressure within the cochlea.

41. The method of claim 40 wherein fluid pressure within the cochlea is increased by controllably altering the first volume of therapeutic fluid.