Details for Patent: 5,458,135

Title:	Method and device for delivering aerosolized medicaments
Abstract:	A device for accurately delivering aerosolized doses of a medicament disperses a measured amount of drug in a measured volume of carrier gas and transfers the resulting aerosol to a chamber prior to inhalation by a patient. The chamber is filled efficiently with the aerosol, and inhalation by the patient draws the aerosol dose into the lungs. This is followed by the inhalation of atmospheric air that will push the initial dose well into the lung interiors. The apparatus optimally includes a dose regulator, a counter, a clock, a dose memory and a signal to indicate when a dose is ready for inhalation. Optimal chamber designs are disclosed.
Inventor(s):	Patton; John S. (San Carlos, CA), Platz; Robert M. (Half Moon Bay, CA)
Assignee:	Inhale Therapeutic Systems (Menlo Park, CA)
Filing Date:	Jul 08, 1992
Application Number:	07/910,048
Claims:	1. A method for producing an aerosolized dose of a medicament for subsequent inhalation by a patient, said method comprising: dispersing a preselected amount of the medicament in a powdered form in a high velocity air stream having a volume in the range from 10 ml to 750 ml of gas to produce the aerosolized dose; and introducing substantially the entire volume of the aerosolized dose into a chamber having an inlet at one end, an open mouthpiece at an opposite end, and a volume in the range from 100 ml to 750 ml, wherein the inlet and mouthpiece are oriented such that medicament entering the chamber through the inlet displaces air initially present in said chamber without substantial loss of medicament through the mouthpiece or within the chamber. 2. A method as in claim 1, further comprising capturing at least about 40% by weight of the medicament delivered to the chamber wherein the medicament remains aerosolized and suspended within the chamber. 3. A method as in claim 1, wherein the medicament is dispersed in an aerosol of particles in the size range of from 1 .mu.m to 5 .mu.m. 4. A method as in claim 3, wherein the medicament comprises a protein or polypeptide active agent. 5. A method as in claim 1, wherein the high velocity air stream is introduced axially into the chamber and the medicament captured within the chamber by an internal baffle disposed transversely across the chamber between the inlet and mouthpiece. 6. A method as in claim 1, wherein the introducing step comprises passing the aerosolized dose through a tangential inlet on the chamber which causes the dose to flow in a vortical pattern. 7. A method for delivering an aerosolized powder medicament to a patient, said method comprising: (a) dispersing a preselected amount of the powder medicament in a high velocity air stream having volume in the range from 10 ml to 750 ml to produce a single aerosolized dose; (b) capturing substantially the entire volume of the aerosolized dose into a chamber having a volume in the range from 100 ml to 750 ml and an open mouthpiece, wherein air initially present in the chamber is displaced without substantial loss of medicament through the mouthpiece and wherein the chamber geometry is such that deposition of medicament against walls within the chamber is minimized; (c) inhaling of the aerosolized dose from the chamber through the mouthpiece by the patient, wherein the patient inhales substantially the entire aerosolized dose followed by ambient air which sweeps the chamber of residual medicament whereby the chamber is refilled with ambient air; and repeating steps (a) through (c) a sufficient number of times to deliver a desired total dosage of the medicament. 8. A method as in claim 7, wherein at least about 40% by weight of the medicament delivered to the chamber remains aerosolized and suspended within the chamber. 9. A method as in claim 7, wherein the medicament is dispersed in an aerosol of particles in the size range of from 1 .mu.m to 5 .mu.m. 10. A method as in claim 9, wherein the medicament comprises a protein active agent. 11. A method as in claim 7, wherein the high velocity air stream is introduced axially through an inlet in the chamber and the medicament is captured within the chamber by an internal baffle disposed transversely across the chamber between the inlet and mouthpiece, and wherein the ambient air enters the chamber is a vortical pattern which sweeps the medicament past the-baffle to the mouthpiece. 12. A method as in claim 7, wherein the introducing step comprises passing the aerosolized dose through a tangential inlet on the chamber which causes the dose to flow in a vortical pattern. 13. An apparatus for producing aerosolized doses of a dry powder medicament, said apparatus comprising: means for introducing a preselected amount of the dry powder medicament into a predetermined volume of flowing air to produce an aerosolized quantity of medicament; a chamber having an ambient air inlet and a patient mouthpiece; means for transferring substantially the entire aerosolized quantity of medicament from the introducing means to an entry point in the chamber; and an internal baffle within the chamber, wherein the transferring means directs the aerosol axially within the chamber and the internal baffle contains the medicament within the aerosol with in a region between the transferring means and the baffle; wherein the volume and geometry of the chamber are selected so that air initially present in said chamber is displaced without substantial loss of medicament through the mouthpiece or within the chamber. 14. An apparatus as in claim 13, wherein the means for aerosolizing the medicament comprises a dry powder reservoir and means for introducing preselected amounts of the dry powder into the flowing air stream. 15. An apparatus as in claim 13, wherein the ambient air inlet is disposed tangentially on the chamber between the transferring means and the baffle, whereby inhalation on the mouthpiece will induce a vortical flow of ambient air to sweep medicament past the baffle. 16. An apparatus as in claim 15, wherein the baffle is hemispherical with a concave surface disposed toward the transferring means. 17. An apparatus as in claim 16, wherein the chamber has a generally cylindrical interior and the means for transferring introduces the aerosolized medicament at a tangential angle so that a vortical flow is established, and wherein the aerosolized medicament enters at one end of the chamber and the mouthpiece is at the other end. 18. An apparatus as in claim 17, wherein the chamber has a spacer tube disposed axially therein to help establish the vortical flow pattern. 19. An apparatus as in claim 13, wherein the chamber has an internal volume in the range from 100 ml to 750 ml. 20. An apparatus as in claim 13, wherein the air inlet is located on the same end of the chamber as the aerosolized medicament entry point, whereby patient inspiration sweeps the chamber with air from the air inlet. 21. An apparatus as in claim 13, wherein the air inlet includes a one-way valve which permits inflow and prevents outflow. 22. An apparatus for producing aerosolized doses of a medicament, said apparatus comprising: means for dispersing a predetermined amount of the medicament in a preselected volume of flowing gas to produce an aerosolized quantity of medicament; a cylindrical chamber having an ambient air inlet at one end and a mouthpiece at the other end; a spacer tube disposed axially in the chamber to help establish the vortical flow pattern; and means for tangentially introducing the aerosolized quantity of medicament from the dispersing means into the chamber so that the medicament will flow along a vortical path in the cylindrical chamber, whereby air is displaced from the chamber without substantial mixing as the chamber is being filled with medicament. 23. An apparatus as in claim 22, wherein the means for dispersing the medicament comprises a dry powder reservoir and means for introducing preselected amounts of the dry powder into the flowing gas stream. 24. An apparatus as in claim 22, wherein the chamber has an internal volume in the range from 100 ml to 750 ml. 25. An apparatus as in claim 22, wherein the air inlet includes a one-way valve which permits inflow and prevents outflow. 26. An apparatus for producing aerosolized doses of a powdered medicament, said apparatus comprising: means for dispersing a predetermined amount of the medicament in a preselected volume of flowing gas to produce an aerosolized quantity of medicament; a cylindrical chamber having a tangential ambient air inlet at one end and a mouthpiece at the other end, wherein the dispersing means is connected to the chamber through an inlet which is on the same end as the ambient air inlet and which is axially aligned with the mouthpiece; and an internal baffle disposed transversely within the chamber so that the internal baffle contains the aerosolized medicament within a region between the introducing means and the baffle, wherein the ambient air inlet is disposed tangentially on the chamber between the introducing means and the baffle, whereby inhalation on the mouthpiece will induce a vortical flow of ambient air to sweep medicament past the baffle. 27. An apparatus as in claim 26, wherein the means for dispersing the medicament comprises a dry powder reservoir and means for introducing preselected amounts of the dry powder into a flowing gas stream. 28. An apparatus as in claim 26, wherein the baffle is hemispherical with a concave surface disposed toward the introducing means. 29. An apparatus as in claim 26, wherein the chamber has an internal volume in the range from 100 ml to 750 ml. 30. An apparatus as in claim 26, wherein the air inlet includes a one-way valve which permits inflow and prevents outflow. 31. An apparatus for producing aerosolized doses of a powdered medicament, said apparatus comprising: means for dispersing a predetermined amount of the medicament in a preselected volume of flowing gas to produce an aerosolized quantity of medicament; a cylindrical chamber having a tangential ambient air inlet at one end and a mouthpiece at the other end, wherein the dispersing means is connected to the chamber through an inlet which is on the same end as the ambient air inlet; and an internal baffle disposed transversely within the chamber so that the internal baffle contains the aerosolized medicament within a region between the introducing means and the baffle, wherein the ambient air inlet is disposed tangentially on the chamber between the introducing means and the baffle, whereby inhalation on the mouthpiece will induce a vortical flow of ambient air to sweep medicament past the baffle. 32. An apparatus as in claim 31, wherein the means for dispersing the medicament comprises a dry powder reservoir and means for introducing preselected amounts of the dry powder into a flowing gas stream. 33. An apparatus as in claim 31, wherein the baffle is hemispherical with a concave surface disposed toward the introducing means. 34. An apparatus as in claim 31, wherein the chamber has an internal volume in the range from 100 ml to 750 ml. 35. An apparatus as in claim 31, wherein the air inlet includes a one-way valve which permits inflow and prevents outflow.