Flow regulator for aerosol drug delivery and methods

• US 20040000309A1
• Filed: 05/14/2003
• Published: 01/01/2004
• Est. Priority Date: 06/18/2002
• Status: Active Grant

• Current Assignee: Novartis Pharma AG (Novartis Ag)
• Original Assignee: Nektar Therapeutics Incorporated
• Inventors: Alston, William
• Granted Patent: US 7,185,651 B2
• Time in Patent Office: Days
• US Class Current: 128/203.15
• CPC Class Codes: A61M 15/0016 located downstream of the dispenser, i.e. traversed by the product
• CPC Class Codes: A61M 15/002 with air flow regulating means
• CPC Class Codes: A61M 15/0086 Inhalation chambers
• CPC Class Codes: A61M 15/0091 mechanically breath-triggered
• CPC Class Codes: A61M 15/0093 without arming or cocking, e.g. acting directly on the delivery valve
• CPC Class Codes: A61M 2202/064 Powder

Abstract

An aerosolization device comprises a housing having a mouthpiece, and a flow path arrangement in fluid communication with the mouthpiece. The flow path arrangement has a flow regulating valve and a threshold valve, where the threshold valve is configured to open at a first vacuum level and to close at a second vacuum level that is less than the first vacuum level. The housing includes a region that is adapted to hold a powder in fluid communication with the flow path arrangement so that air drawn through the mouthpiece opens the threshold valve once the first vacuum level is exceeded and remains open until the vacuum falls below the second vacuum level. The flow rate of the air drawn through the mouthpiece is regulated by the flow regulating valve to remain within a certain range while the threshold valve remains open.

Claims

1. A method for regulating air flow, the method comprising:

providing a flow path arrangement having a flow regulating valve and a threshold valve, wherein the threshold valve is configured to open at a first vacuum level and to close at a second vacuum level that is less than the first vacuum level;

producing a vacuum within the flow path arrangement sufficient to open the threshold valve and to permit a gas to exit the flow path arrangement at a certain flow rate;

maintaining the vacuum above the second vacuum level for at least a certain time to maintain the threshold valve open, with the flow regulating valve regulating the flow rate to be within a certain range while the threshold valve remains open.

2. A method as in claim 1, wherein the flow path arrangement has a first flow path that divides into a second flow path and a third flow path, wherein the threshold valve is in the first flow path, the flow regulating valve is in the second flow path, and the powder is coupled to the third flow path.

3. A method as in claim 1, wherein the first vacuum level is in the range from about 20 cm H₂O to about 50 cm H₂O, and wherein the second vacuum level is in the range from about 0 cm H₂O to about 12 cm H₂O.

4. A method as in claim 3, wherein the second vacuum level is less than about 8 cm H₂O.

5. A method as in claim 1, wherein the certain flow rate range is about 12 liters/min to about 16 liters/min for vacuums of about 15 cm H₂O to about 80 cm H₂O.

6. A method as in claim 1, wherein the flow regulating valve comprises at least one deformable wall and an opposing surface, wherein the deformable wall moves toward the opposing surface as the vacuum downstream of the flow regulating valve increases to regulate the flow rate.

7. A method as in claim 1, wherein the flow regulating valve comprises a valve body having an inlet end, an outlet end and a gas flow passage between the inlet end and the outlet end, wherein the valve body is constructed of a resilient material and wherein the valve body at the outlet end has a central region and a plurality of extending regions that extend outwardly from the central region, and wherein the extending regions are drawn together to limit the flow of gases through the gas flow passage as the vacuum downstream of the outlet end increases.

8. A method for aerosolizing a powder, the method comprising:

providing a flow path arrangement having a flow regulating valve and a threshold valve, wherein the threshold valve is configured to open at a first vacuum level and to close at a second vacuum level that is less than the first vacuum level;

providing an amount of powder that is in fluid communication with the flow path arrangement;

inhaling to produce a vacuum within the flow path arrangement sufficient to open the threshold valve and to permit a gas to exit the flow path arrangement at a certain flow rate;

continuing to inhale to maintain the vacuum above the second vacuum level for at least a certain time to maintain the threshold valve open and to aerosolize the powder, with the flow regulating valve regulating the flow rate to be within a certain range while the threshold valve remains open.

9. A method as in claim 8, wherein the flow path arrangement has a first flow path that divides into a second flow path and a third flow path, wherein the threshold valve is in the first flow path, the flow regulating valve is in the second flow path, and the powder is coupled to the third flow path.

10. A method as in claim 8, wherein the first vacuum level is in the range from about 20 cm H₂O to about 50 cm H₂O, and wherein the second vacuum level is in the range from about 0 cm H₂O of about 12 cm H₂O.

11. A method as in claim 10, wherein the second vacuum level is less than about 8 cm H₂O.

12. A method as in claim 8, wherein the flow path arrangement is coupled to a mouthpiece, and further wherein the inhaling step comprising inhaling through the mouthpiece.

13. A method as in claim 8, wherein the certain flow rate range is about 12 liters/min to about 16 liters/min for vacuums of about 15 cm H₂O to about 80 cm H₂O.

14. A method as in claim 8, wherein the flow regulating valve comprises at least one deformable wall and an opposing surface, wherein the deformable wall moves toward the opposing surface as the vacuum downstream of the flow regulating valve increases to regulate the flow rate.

15. A method as in claim 14, wherein the flow regulating valve comprises a valve body having an inlet end, an outlet end-and a gas flow passage between the inlet end and the outlet end, wherein the valve body is constructed of a resilient material and wherein the valve body at the outlet end has a central region and a plurality of extending regions that extend outwardly from the central region, and wherein the extending regions are drawn together to limit the flow of gases through the gas flow passage as the vacuum downstream of the outlet end increases.

16. A method as in claim 8, wherein the powder is contained within a receptacle, and wherein the gas flow through the flow path arrangement flows through the receptacle to extract and aerosolize the powder.

17. An aerosolization device, comprising:

a housing having a mouthpiece;

a flow path arrangement in fluid communication with the mouthpiece, the flow path arrangement having a flow regulating valve and a threshold valve, wherein the threshold valve is configured to open at a first vacuum level and to close at a second vacuum level that is less than the first vacuum level;

wherein the housing includes a region that is adapted to hold a powder in fluid communication with the flow path arrangement, wherein air drawn through the mouthpiece opens the threshold valve once the first vacuum level is exceeded and remains open until the vacuum falls below the second vacuum level, and the flow rate of the air drawn through the mouthpiece is regulated by the flow regulating valve to remain within a certain range while the threshold valve remains open.

18. A device as in claim 17, wherein the flow path arrangement has a first flow path that divides into a second flow path and a third flow path, wherein the threshold valve is in the first flow path, the flow regulating valve is in the second flow path, and the powder is coupled to the third flow path.

19. A device as in claim 18, wherein the second flow path and the third flow path combine to a fourth flow path that is connected to the mouthpiece.

20. A device as in claim 17, wherein the first vacuum level is in the range from about 20 cm H₂O to about 50 cm H₂O, and wherein the second vacuum level is in the range from about 0 cm H₂O to about 12 cm H₂O.

21. A method as in claim 20, wherein the second vacuum level is less than about 8 cm H₂O.

22. A device as in claim 17, further comprising a receptacle that is held within the region, the receptacle having a chamber that is adapted to hold the powder.

23. A device as in claim 17, wherein the certain flow rate range is about 12 liters/min to about 16 liters/min for vacuums of about 15 cm H₂O to about 80 cm H₂O.

24. A device as in claim 17, wherein the flow regulating valve comprises at least one deformable wall and an opposing surface, wherein the deformable wall moves toward the opposing surface as the vacuum downstream of the flow regulating valve increases to regulate the flow rate.

25. A device as in claim 17, wherein the flow regulating valve comprises a valve body having an inlet end, an outlet end and a gas flow passage between the inlet end and the outlet end, wherein the valve body is constructed of a resilient material and wherein the valve body at the outlet end has a central region and a plurality of extending regions that extend outwardly from the central region, whereby the extending regions are drawn together to limit the flow of gases through the gas flow passage as the vacuum downstream of the outlet end increases.

26. A valve comprising:

a valve body having an inlet end, an outlet end and a gas flow passage between the inlet end and the outlet end, wherein the valve body is constructed of a resilient material and wherein the valve body at the outlet end has a central region and a plurality of extending regions that extend outwardly from the central region, whereby the extending regions are drawn together to limit the flow of gases through the gas flow passage as the vacuum downstream of the outlet end increases.

27. A valve as in claim 26, wherein each extending region comprises a pair of walls having a base end and a top end, and wherein the top ends are connected at an acute angle.

28. A valve as in claim 27, wherein each extending region is connected to two adjacent extending regions at the base ends of the walls to define the central region.

29. A valve as in claim 28, wherein the number of extending regions is eight.

30. A valve as in claim 26, wherein the outlet end includes two orthogonal axis, wherein one of the axis passes through two of the extending regions, and the other orthogonal axis passes through the other two extending regions.

31. A valve as in claim 26, wherein the resilient material comprises silicone rubber.

32. A valve as in claim 26, further comprising a boundary layer step on the valve body near the inlet end.