Aerosol delivery device with a dosage indicator

Abstract

Provide an indicator when the user has completed a predetermined amount of inhalation or when the inhalation of a prescribed dose of the drug has been completed. 【Solution means】The drug delivery system includes a chamber housing that defines an internal volume. The chamber housing has an inlet adapted to receive a dose of the drug and an outlet spaced from the inlet. The inlet and the outlet are in fluid communication with the internal volume. A fluid channel is in fluid communication with the internal volume. A dose indicator is translatable within the fluid channel from a pre-inhalation position to a dose-completed position, and the positioning of the dose indicator at the dose-completed position indicates that the administration of the drug through the outlet has been completed. A method of using the system and an assembly are also provided.

Description

Technical Field

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 342,452, filed on May 16, 2022, entitled "Aerosol Delivery Device With Completed Dosage Indicator", the entire disclosure of which is incorporated herein by reference.

[0002] The present invention generally relates to an aerosol delivery device, such as a holding chamber, configured to provide an indicator when a user has completed a predetermined amount of inhalation or when a user has completed inhalation of a prescribed dosage of a drug, and to a method of delivering an aerosol drug and a method of assembling a delivery device indicating completion of inhalation of a dosage of the drug.

Background Art

[0003] The use of aerosol drug delivery devices and systems (hereinafter referred to as "aerosol delivery systems") for administering drugs in aerosol form to a patient's lungs by inhalation is well known in the art. Such devices and systems include, for example, pressurized metered-dose inhalers (pMDIs), pMDI add-on devices such as holding chambers, devices including a chamber housing and an integrated actuator suitable for a pMDI canister, nebulizers, dry powder inhalers, and other such devices. Some aerosol delivery systems are configured to provide a visual indication to a caregiver when a patient is inhaling, but such systems typically do not warn the user or caregiver that the user has inhaled all of the drug.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

[0005] In one aspect, an embodiment of a drug delivery system includes a chamber housing that defines an internal volume. The chamber housing has an inlet adapted to receive a dose of drug and an outlet spaced from the inlet. The inlet and the outlet are in fluid communication with the internal volume. A fluid channel is in fluid communication with the internal volume. A dose indicator is translatable within the fluid channel from a pre-inhalation position to a dose-completed position, and the positioning of the dose indicator at the dose-completed position indicates that the administration of the drug through the outlet is complete. In one embodiment, the dose indicator is visible through the fluid channel as the dose indicator translates between the pre-inhalation position and the dose-completed position.

[0006] In yet another aspect, the drug delivery system includes a chamber housing that defines an internal volume and has an inlet adapted to receive a dose of drug and a user interface disposed longitudinally spaced from the inlet. The inlet and the user interface are in fluid communication with the internal volume. A fluid channel is in fluid communication with the internal volume and extends longitudinally. A dose indicator is translatable within the flow path from a pre-inhalation position proximate the user interface to a dose-completed position proximate the inlet. The positioning of the dose indicator at the dose-completed position indicates that administration of the drug via the user interface is complete. The dose indicator includes a turbine rotatable within the fluid channel as the dose indicator translates between the pre-inhalation position and the dose-completed position. In various embodiments, the dose indicator is observable within the fluid channel; for example, the dose indicator moves within the fluid channel and is visible or audible when it reaches the dose-completed position.

[0007] In another aspect, in one embodiment of the drug delivery system, it includes a chamber housing that defines an internal volume and has an inlet adapted to receive a dose of drug and a user interface disposed longitudinally spaced from the inlet. The inlet and the user interface are in fluid communication with the internal volume. A fluid channel in fluid communication with the internal volume extends longitudinally. A rod is disposed within the fluid channel. A dose indicator is translatable within the flow path from a pre-inhalation position proximate the user interface to a dose-completed position proximate the inlet. The positioning of the dose indicator at the dose-completed position indicates that administration of the drug via the user interface is complete. The dose indicator includes a piston that is slidable along the rod within the fluid channel as the dose indicator translates between the pre-inhalation position and the dose-completed position and is visible through the fluid channel.

[0008] In another aspect, one embodiment of a method of delivering an aerosolized drug comprises placing a dosage of the aerosolized drug in the internal volume of a chamber housing; withdrawing a dosage of the aerosolized drug from the internal volume by inhalation through a user interface coupled to the chamber housing; translating a dosage indicator in a flow path in fluid communication with the chamber housing from a pre-inhalation position to a dosage-completed position; observing the translation of the dosage indicator; and terminating inhalation when the dosage indicator reaches the dosage-completed position. In one embodiment, the dosage indicator rotates as it translates from the pre-inhalation position to the dosage-completed position.

[0009] In various aspects and embodiments, significant advantages are provided over other drug delivery systems and methods. For example, but not limited to, the movement of the dosage indicator enables the user and caregiver to visually and / or audibly detect that the user has inhaled all of the drug. This feedback system is believed to be particularly suitable for caregivers and users who may not be able to generate an inhaler sufficient to inhale a full dosage of the drug in a single breath. In contrast to conventional devices that can only provide an indication that an inhalation flow is occurring, rather than indicating how much has been inhaled, the dosage indicator provides an indication to the user when the entire pre-determined regulated amount of the drug has been inhaled. Further, the dosage indicator is observable (e.g., visible and / or audible) to both the user and caregiver in one embodiment.

[0010] The foregoing paragraphs are provided as a general introduction and are not intended to limit the appended claims. The various preferred embodiments will be best understood by reference to the following detailed description in conjunction with the accompanying drawings, which are included to provide a further understanding and are incorporated in and constitute a part of this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0011]

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DETAILED DESCRIPTION OF THE INVENTION

[0012] As used herein, the term "plurality" is to be understood to mean two or more. The term "longitudinal direction" as used herein is, for example, the length or longitudinal dimension 2 between opposing ends of a holding chamber or fluid channel, or a meaning related thereto. The terms "lateral direction" and "transverse direction" as used herein mean being located from side to side (front and back of the work surface), being directed laterally, or extending from side to side, and refer to the lateral direction 4 that is orthogonal to the longitudinal direction. For example, the X direction can correspond to the longitudinal direction that is horizontal when the device is in the use position, the Y direction can extend in the vertical direction when the device is in the use position, and the Z direction can correspond to the lateral direction that is also horizontal when the device is in the use position. The term "direction" corresponds to an axis or line, not a vector. The term "coupled" means, whether directly or indirectly, for example, being connected to or engaged with an intervening member, and the engagement does not need to be fixed or permanent, but may be fixed or permanent (or integral), and includes both mechanical and electrical connections. The terms "first", "second", etc. as used herein do not mean to assign to a particular component so designated, but rather simply refer to such components in numerical order as addressed, meaning that the component designated as "first" may, depending on the order of reference, later become such a component of "second". For example, the "first" side may, depending on the order of reference, later be referred to as the "second" side. Also, the designations "first" and "second" do not necessarily mean that the two features, components, or values so designated are different. For example, it should be understood that the first side may be the same as the second side, and each simply means being applied to separate identical components.As used herein, the term "substance" includes, without limitation, any substance having a therapeutic benefit, including any agent, the terms "user" and "patient" include humans and animals, and the term "aerosol delivery device or system" includes pressurized metered-dose inhalers (pMDIs), pMDI add-on devices such as devices having a holding chamber, devices including a chamber housing and an integrated actuator suitable for a pMDI canister, nebulizers, and dry powder inhalers.

[0013] Figures 1, 6, 8A - C, and 25 illustrate one embodiment of an aerosol delivery system 100. The system 100 includes a holding chamber 102 or conduit, an interface 104, an inhalation valve 132, and a source of substance such as a pMDI canister 106 attached to the rear end 107 of the holding chamber 102. The holding chamber 102 includes a chamber housing 108 having a generally cylindrical cross - sectional shape that defines a space of an internal volume 110 for receiving an aerosolized drug from the pMDI 106. The front end of the chamber housing 108 includes an outlet 112 configured as an opening in fluid communication with the internal volume 110 of the chamber housing 108 in one embodiment. The outlet 112 defines the periphery of the flow path as it exits the opening. The interface 104 can be configured as a mouthpiece, a mask (nasal or oral / nasal), a tube body, or other suitable user interface in fluid communication with the outlet / aperture 112. The inhalation valve 132 can be disposed over the opening to provide a one - way flow through the opening during inhalation, but prevent backflow into the internal volume 110 during exhalation. The exhalation valve 115 can be provided to allow a one - way flow to the ambient environment surrounding the system 100 during exhalation, but prevent entrainment of air through the exhalation opening during inhalation. The rear end 107 of the chamber housing 108 includes an inlet 116 configured in one embodiment as an opening suitable for receiving the mouthpiece 118 of a pMDI receptacle 120 (also known as an actuator boot) that houses the pMDI canister 106, and is attached to a detachable and flexible backpiece 114, or an adapter. The canister 106 includes a valve stem 122 disposed in a well 124 at the bottom of the receptacle 120. The inlet 116 is in fluid communication with the internal volume 110. Examples of pMDI adapters and canisters that may be used with the holding chamber 102 are also described in U.S. Pat. Nos. 5,012,803, 5,012,804, 5,848,588, and 6,293,279, the entire contents of each of which are incorporated herein by reference.Other aerosol delivery systems can include devices having one or more outlets and one or more inlets that communicate with an internal volume, which can have various one or more internal volumes that can be filled with an aerosol agent, including pMDI canisters, nebulizers, dry powder inhalers, and other devices having a chamber housing and integrated actuator suitable for such devices. The holding chamber 102 extends in the longitudinal direction 2, and the inlet 116 and the outlet 112 are spaced apart in the longitudinal direction.

[0014] In one embodiment, by being able to apply a force F to the canister, the valve stem 122 of the pMDI canister is moved to discharge a predetermined amount of the agent in aerosol form from the discharge end of the pMDI receptacle, such as the mouthpiece 118, into the internal volume 110 of the chamber housing 108. The aerosol agent particles in the internal volume 110 and the chamber housing 108 are then drawn out through the outlet 112 by inhalation through the interface 104 by the user / patient.

[0015] The pMDI canister 106 contains a substance, preferably a pressurized drug suspension or solution. For example, the substance to be formulated can be an HFA propellant drug suspension or solution formulation. Other drugs, or drugs and propellants such as CFCs, can also be used. Although the described embodiments relate to an aerosol delivery system for delivering an aerosol agent from a pMDI, it should be pointed out that other aerosol delivery systems that can be used within the spirit of the present invention are contemplated. For example, it is contemplated that a completed dosage indicator can be incorporated into aerosol delivery systems such as existing ventilator systems, dry powder inhalers, and nebulizers in a manner similar to that described below. Examples of nebulizers that can be adapted to include such an indicator are disclosed in U.S. Pat. Nos. 5,823,179 and 6,044,841, the entire contents of which are incorporated herein by reference.

[0016] The present invention is not limited to the treatment of human patients. For example, it is contemplated that the full dose indicator can be incorporated into a mask for administering a drug to an animal, including, for example and without limitation, horses, cats, dogs, etc.

[0017] Referring to FIGS. 1, 5-11, 17-22, 25-28, and 33-38, an aerosol delivery system 100 (also known as an aerosol delivery device) comprises fluid channels 150, 250 and dose indicators 160, 260. In one embodiment, the dose indicator 160 is configured as a turbine 170. In an alternative embodiment, the dose indicator 260 is configured as a piston 270. In one embodiment, the fluid channels 150, 250 are configured as tubes or long tubular structures mounted longitudinally 2 on or extending longitudinally 2 along a side, e.g., an upper portion, of the holding chamber 102, such that the fluid channels are visible to the user 148 engaging the interface and / or a nearby caregiver. As shown in FIGS. 11, 26, and 36-38, the fluid channels 150, 250 have a pair of laterally spaced insertion portions 192 or flange portions extending laterally outward from a central base 191. The insertion portions 192 are received in a pair of channels 194 or slots formed in a guide 196 disposed at the upper portion of the holding chamber. The guide 196 may be integrally formed with the holding chamber 102. The fluid channel 150 is coupled to the holding chamber by sliding the insertion portion 192 into the slot 194 until the fluid channel is in fluid communication with the internal volume. In other embodiments, the fluid channel may be integrally formed with the holding chamber as a single piece. The fluid channels 150, 250 or the tubular bodies may be transparent such that a user or caregiver can view the interior of the fluid channels. The fluid channels 150, 250, or their internal spaces, are in fluid communication with the internal volume 110 of the holding chamber when installed. In one embodiment, the fluid channel has an inlet 152, or an opening, and an outlet 154, or an opening, these outlets being in fluid communication with and defining an inlet 156 of the internal volume. The outlet 154 communicates with the holding chamber 102 near the inhaler adapter 114 (distal), while the inlet 152 is disposed near the interface 104 (e.g., a mouthpiece / mask) and is in direct fluid communication with the ambient air surrounding the system 100.In another embodiment, the fluid channel can have an outlet that is in direct fluid communication with the user interface, rather than the internal volume of the holding chamber.

[0018] Dosage indicators 160, 260 are movable longitudinally 2 within fluid channels 150, 250 from a pre-inhalation position to a dosage completion position. In one embodiment, dosage indicator 160 is translatable and rotatable within fluid channel 150 from a pre-inhalation position to a dosage completion position. The phrase "pre-inhalation position" refers to the position of the dosage indicator immediately prior to inhalation by the user via the aerosol delivery device, as shown, for example, in FIG. 7A. The phrase "dosage completion position" refers to the position of the dosage indicator after a predetermined or defined amount of aerosolized drug has been administered within the holding chamber and the drug has been deposited in the user's lungs, for example, through an inhaler. In other words, positioning the dosage indicator at the dosage completion position indicates to the user and caregiver that complete administration of the dosage of medicine through the outlet has been achieved, regardless of how many inhalation sequences (e.g., 1 or more) have occurred. In one embodiment, as shown in FIG. 7C, the dosage indicator is in the dosage completion position. The term "translatable" refers to the displacement or movement of a component within a space defined by the X, Y, and / or Z axes such that, in the absence of rotation, the component has different X, Y, and / or Z coordinates after translation. For example, the dosage indicator can be translatable only in the X direction. It should be understood that the component can further rotate about any of the X, Y, and / or Z axes before, during, and / or after "translating". The component can be translated by sliding, rolling, or other types of movement. In this way, a component such as a dosage indicator can simultaneously translate (move a distance within the space from a first position to a second position) and rotate as it translates between a first position and a second position. In one embodiment, dosage indicator 160 may be transparent or see-through as dosage indicator 160 is translated and rotated between a pre-inhalation position and a dosage completion position and is visible through and within fluid channel 150 made of a transparent material. In other embodiments, it should be understood that, for example, as shown in FIG. 25, dosage indicator 260 translates only, for example, by sliding, between a pre-inhalation position and a dosage completion position.

[0019] For example, in one embodiment shown in FIGS. 1, 8A-10, the turbine 170 is rotatable to translate from a pre-inhalation position to an administration completion position. In one embodiment, the dose indicator 160 is translatable along a linear path between the pre-inhalation position and the administration completion position. The term "linear" means movement along a straight line. In other embodiments, the dose indicator 160 is translatable along a planar path between the pre-inhalation position and the administration completion position, which means that the dose indicator moves within a plane defined by two axes (e.g., X and Y), but can also rotate about an axis (Z) perpendicular to the plane. In various embodiments, the dose indicators 160, 260 are closer to the user interface 104 at the pre-inhalation position than at the administration completion position, which means that the dose indicator moves away from the user 148 during the inhalation sequence. In other embodiments, the relative positioning may be reversed, and the dose indicator is farther from the user interface at the pre-inhalation position than at the administration completion position, which means that the dose indicator moves in a direction away from the user during the inhalation sequence.

[0020] In various embodiments, the fluid channels 150, 250 include tracks 180, 280, and the dose indicators 160, 260 are movable along the tracks 180, 280 between the pre-inhalation position and the administration completion position. The dose indicator can slide (translate) or roll (translate and rotate) along the track. As shown in FIGS. 9 and 10, the track 180 can be configured to have a dip 182 adjacent to the dose indicator when disposed at the pre-inhalation position. The interface between the dose indicator 160 and the track 180 can provide an auditory indicator adapted to provide an audible signal when the dose indicator has translated to the administration completion position.

[0021] As shown in FIG. 25, the track 280 can be configured as a rod 402 that extends longitudinally in the center of the channel, and the opposing ends of the track, or rod, are held by fixtures 404, 406 (e.g., hubs) such that the track, or rod, is suspended in the center of the channel. In one embodiment, the length of the channel is about 79 mm and is optimized, along with other piston, rod, and valve parameters, to indicate that the patient has inhaled the required amount into the chamber. The inner shape of the fluid channel is designed to conform to the outer contour of the piston, and there is some space for the airflow around the piston.

[0022] The opening 154 connecting the channel and the chamber is designed to minimize the resistance to the flow of air between the channel and the chamber. In this embodiment, it has an opening of 10 mm × 9 mm, although it may be smaller or larger.

[0023] Referring to FIGS. 25, 27, 28, and 33-35C, the dosage indicator 260 is configured as a piston 270 having a central disk 409 or disk portion that extends radially outward from the central hub portion 410. The hub portion 410 is a bush-like extension that extends longitudinally from one side of the disk portion, as shown in FIG. 34C, or from both sides of the disk portion, as shown in FIGS. 28, 34A, and 34B. The longitudinally extending through-opening 412 extends through the piston and is shaped to receive the rod. The dosage indicator or piston is slidably disposed on the rod 402 such that the dosage indicator can move along the length of the channel as air passes through the channel configured as a long tubular body. The disk 409, or large fins, creates resistance and moves along the shaft or rod 402 through the channel. In one embodiment, the piston 270 is a thin plastic disk having a central bush feature. The bush allows the piston to slide on the rod when air pushes against the disk. In one embodiment, the outer diameter of the piston is 12 mm, but can range from mm to 20 mm (depending on other design variables). In the case of high sensitivity, as shown in FIGS. 34A-C, the weight of the piston can be reduced by making the fin walls thinner. Overall, it is desirable to lower the moment of inertia for high sensitivity. The piston weight varies as shown in Table 1, but it should be understood that depending on other design characteristics, weights outside the stated range may also be suitable. Table 1: Piston Weight TIFF2025516831000002.tif28153

[0024] The piston bush 410 extends from the disk 409 to prevent the disk from tilting and binding on the rod 402 and to provide smooth movement along the shaft. In various embodiments, the difference in diameter between the piston bush and the shaft may be 0.1 mm to 0.13 mm for a bush of length 2-5 mm, but the difference in diameter of the bush can be on the order of 0.05 mm and 1 mm depending on the length of the bush.

[0025] In one embodiment, the bushing inner diameter is about 3.4 mm and the rod outer diameter is about 3.18 mm for adult, infant and pediatric use. The inner diameter of the bushing can be about 6 mm in size and about 1 mm in size. In one embodiment, the shape of the piston rod 402 is cylindrical / tubular, extends along the length of the channel, and connects at the distal and proximal ends of the channel. The rod can be made of stainless steel, but can be made of PP plastic (or other polyolefins, nylon, MABS, polycarbonate).

[0026] The piston fin or disk can be of any two-dimensional shape, but the disk should have an appropriate defined weight and edge gap for air to pass through (i.e., the channel should have a matching shape). Non-circular disk shapes may require alignment features on the rod to prevent the piston from rotating about the rod and contacting the fluid channel wall.

[0027] The rod 402 and the opening 412 may be cylindrical such that the piston rotates about the axis of the rod, or the opening and the rod may have a non-cylindrical shape, such as a keyed cross-sectional shape like cross-section X, that prevents the piston from rotating about the axis. The first fixture 406 (e.g., a hub) is formed on the first end cap and can close one end of the channel. The second fixture 404 is formed on the valve assembly housing 420 and defines a second cap that closes the second end of the fluid channel. The outlet 154 is formed in the side wall of the fluid channel. A slight clearance can be provided between the outer peripheral surface of the piston 270 and the inner surface of the fluid channel that defines the elongated chamber so that there is no interference and associated friction between the piston and the fluid channel. Rather, the piston 270 slides freely along the guide or rod 402. In one embodiment, the clearance between the periphery of the disk or fin and the inner surface of the fluid channel is between 0.1 mm and 2 mm, inclusive. In an exemplary embodiment, the radial clearance can be 0.25 mm for child / adult use and 0.35 mm for infant use, which allows the piston to slide freely within the channel without interfering with the periphery, but also creates sufficient restraint such that the piston 270 can be pulled down the length of the channel.

[0028] In other embodiments, there may be contact between the piston and the inner surface. In one embodiment, the inner surface of the fluid channel functions as a guide and the outer surface of the piston rides along the fluid channel and is guided by the fluid channel. In this embodiment, the rod can be omitted.

[0029] Referring to FIGS. 1, 4A - B, 7A - C and 13 - 16, turbine 170 includes a shaft 184 and several branched fin blades 186 that generate drag and extend radially from the shaft 184. When exposed to an air flow, the turbine rotates or spins about the center of the shaft 184. In one embodiment, the shaft 184 extends laterally outward in the Z - direction beyond the width of the blades / fins 186 on both sides thereof, and at least a portion of the shaft is configured as a pinion gear 188 having a plurality of teeth 198 spaced circumferentially. The fin blades 186 may be curved or flat. In one embodiment, the teeth 198 are aligned with the blades 186, as shown, for example, in FIGS. 4A and 14.

[0030] In one embodiment, the fluid channels include a pair of laterally - spaced tracks 180 defined by slots or channels 200 each extending longitudinally. In one embodiment, each track has upper and lower surfaces 202, 204 that define the fluid channel, as shown, for example, in FIG. 12. One or both of the upper and lower surfaces may include or be configured as a rack 206. The rack may be straight or disposed in a plane and is configured with a plurality of teeth 207. The turbine 170 is disposed or positioned within the internal space of the fluid channel 150, and the pinion gear 188 is disposed and engaged on a rack embedded in a slot on the side of the channel. The end 208 of the shaft is spaced from the side wall 210 of the fluid channel 200, providing a clearance such that the end 208 of the shaft does not bind to the wall 210 and cause excessive friction, allowing the turbine 170 to roll (translate and rotate) freely within the fluid channel 150. In an embodiment, the gap between the end 208 of the shaft and the side wall 210 is less than 0.05 mm and not more than 3 mm. In one embodiment, the gap is 0.5 mm.

[0031] When user 148 inhales through user interface 104 such as a mouthpiece or a mask, the mixture of aerosol drug and air disposed in the internal volume 110 of the holding chamber 102 is aspirated through the inhalation valve 132 such that air reverse-fills / refills the holding chamber. In one embodiment, the air that refills the holding chamber 102 flows in from the ambient environment through two or more inlets. In one embodiment, the reverse-fill air can flow in from three sources: through the inhaler 106 and inlet 116 (pMDI and SMI), through inlet 156 that communicates with the fluid channel 150, and through one or more inlets 220 within the MDI adapter (backpiece) 114 spaced from inlet 116. When air is aspirated through the fluid channel 150, the turbine 170 begins to move from its pre-inhalation position, where the turbine is disposed at the proximal end of the holding chamber, towards the distal end. Depending on the user's inhalation rate over time, when the patient has inhaled an amount sufficient to reliably empty the drug in the internal volume of the chamber, the turbine 170 hits the stop 212 at or near the end of the fluid channel 150 that defines the administration completion position. This volume can vary, for example, by age group, and can be 500 mL for adults, 300 mL for children, 150 mL for infants, or the like. To reset the dosage indicator 160 for the next use, the user simply tilts the holding chamber 102 (e.g., by tilting counterclockwise as shown in FIG. 1) such that the turbine 170 winds back to its proximal pre-inhalation position.

[0032] In the embodiment of the dosage indicator of FIG. 25, when user 148 inhales, piston 270 slides along the guide from the proximal end to the distal end of channel 150, thereby indicating that the user has inhaled the full dosage of the drug. The user can tilt the VHC until the piston slides along the guide and returns to the starting position. Since there is an interface between the piston and the guide, the system is not very sensitive to the angular displacement of the entire device, and the device can be rotated up to an angle of 30 degrees to return the piston to the pre-inhalation position. The configurations of inhaler 106 and receptacle 120 are diverse, and thus the inhaler flow resistance, which depends on the shape of the inhaler and the receptacle air passage 121, is also diverse. In one embodiment, ambient air that refills the internal volume 110 during inhalation enters the chamber only through first and second inlets 116, 156 defined, for example, by mouthpiece portion 118 disposed within inlet 116 and inlet 156 in communication with fluid channel 150. The difference in resistance between different inhalers / receptacles changes the airflow through fluid channel 150 depending on which inhaler / receptacle is used, and thus can result in different movement speeds of turbine 170. For example, a combination of inhaler / receptacle with higher resistance promotes the airflow through fluid channel 150 with lower resistance more. Conversely, when the inhaler / receptacle has low resistance, more air passes through the inhaler / receptacle compared to fluid channel 150, which may have relatively high resistance, and thus results in a different inhalation amount response from turbine 170. In one embodiment, turbine 170 is calibrated to the median resistance across all types of inhalers / receptacles that would be used with the aerosol delivery device, or turbine 170 is calibrated to the most resistant inhaler / receptacle, and the dosage indicator can reach the dosage completion position of the least resistant inhaler.

[0033] In an alternative embodiment, one or more third inlets 220 are provided such that they are in fluid communication with the internal volume 110. In one embodiment, a pair of inlets 220 are provided in the backpiece 114, each inlet 220 comprising a variable size opening. In one embodiment, a one-way, variable valve 222 is disposed over the inlet. The inlet 220 and valve 222 may be directly incorporated into the holding chamber, or the inlet and valve may be incorporated into the backpiece or adapter 114, for example as shown in FIGS. 1 and 3. The valve 222 is designed to open when the inhalation resistance through the inhaler / receptacle is high and remain closed when the resistance is low. Referring to FIG. 24, the valve 222 remains closed for inhalers with the lowest resistance, such as the ProAir HFA inhaler with a built-in counter (square mouthpiece), and opens to increase the airflow as the resistance of inhalers such as the Proventil HFA inhaler with a yellow 3M boot increases. The valve 222 is made from an elastomeric material such as silicone or TPE. In one embodiment, the valve 222 is disposed on the backpiece 114 to facilitate the flow of air through the chamber and assist in discharging the suspended medicament into the patient's lungs. In this way, the variable opening size is defined by one or more one-way inhalation valves 222 disposed over one or more inlets 220.

[0034] The embodiment of the dose indicator of FIG. 26 includes only two air paths to the holding chamber, while the embodiment of FIG. 1 includes three air paths. In the embodiment of FIG. 26, the flow in the fluid channel is controlled by a valve assembly 422 disposed at the inlet 152 of the fluid channel. It should be understood that a similar valve assembly can also be used with the dose indicator shown in FIG. 1. In this way, the inlet opening 152 of the fluid channel includes a valve for restricting the airflow, and the outlet opening 154 communicates with the chamber.

[0035] As shown in FIGS. 25 and 29 - 31, the valve assembly 422 includes a housing 420 that defines an inlet 424. A valve 430 is adjustably mounted above the inlet and is arranged in a normally open configuration. The valve 430 avoids the need for additional openings in the back piece. The valve takes into account the differences in resistance associated with various inhalers that can potentially affect the movement of the piston. As described above, this system can be used with various inhalers each having a different flow resistance. Inhalers with high resistance tend to move the piston 270 very quickly through the fluid channel, while inhalers with low resistance tend to move the slider slowly through the channel. To achieve consistent performance across the range of inhalers, the valve 430 is arranged to "choke" the flow through the fluid channel for high - resistance inhalers so that the piston 270 does not move too quickly within the fluid channel. In high - resistance inhalers, a large amount of air flows through the fluid channel, and the negative pressure generated by the flow may close the valve 430, i.e., move it to engage the valve seat 432, thereby slowing or stopping the movement of the piston 270 within the fluid channel during, for example, inhalation, and enabling the piston to behave similarly to when used with a low - resistance inhaler. In such an embodiment, the user may need to take multiple breaths for the piston 270 to reach the end of the fluid channel. In this way, the valve response is proportional to the resistance of the inhaler. For example, when a very low - resistance inhaler is used, the valve 430 may remain open and not move, and when a very high - resistance inhaler is used, the valve 430 is very responsive and closes completely against the valve seat 432, and when a medium - resistance inhaler is used, the valve may only close partially. The valve assembly 422 avoids the need for a valved back piece that would introduce another passage communicating with the holding chamber and associated variations.

[0036] When the user inhales through the mouthpiece, the aerosolized drug and air mixture from the chamber is drawn through the mouthpiece valve. The outside air that replenishes the chamber during the patient's inhalation can come from two sources, either through the inhaler (pMDI and SMI) or through a channel with a valve. When air is drawn through the channel, the piston 270 begins to move from one end of the chamber towards the other end. The user's inhalation rate over time causes the piston to hit the end of the channel when the patient has inhaled an amount sufficient to empty the drug in the chamber. The impact of the piston hitting the end of the channel audibly indicates that dosing is complete. The volume may vary depending on the patient / age group, for example, about 500 mL for adults, about 300 mL for children, and about 150 mL for infants. The one-way variable valve 430 accommodates this difference. Specifically, the valve 430 closes the inlet as the valve biases against the valve seat 432 when the inhalation resistance through the inhaler is high, and remains open when the resistance through the inhaler is low. The valve's response to the air flow through the channel enables the valve to maintain a consistent air flow through the channel, so that the piston can indicate when sufficient air has passed through the chamber. The valve remains closed for inhalers with the lowest resistance, such as the Pro-Air HFA inhaler with a built-in counter, and is adjusted to open to increase the air flow as the resistance of the inhaler increases, such as the Proventil HFA inhaler. The valve may be made of an elastomeric material such as silicone or TPE.

[0037] The tidal volume and the maximum inhalation speed vary among different age groups, with infants having the lowest inhalation speed and adults having the highest inhalation speed. In one embodiment, the piston can have a high sensitivity (<7 L / min) to the inhaler for all age groups. To accommodate a high-sensitivity valve for users with a large inhalation volume, the piston may move too quickly to the distal end of the channel, so it may be necessary to extend the overall length of the channel, for example, to 2 to 3 times the nominal length, assuming that the resistance due to the increased channel length is not too high. To accommodate and adjust for this difference, the valve and piston sensitivity can be varied. Further, the valve 430 allows for consideration of the friction between the piston and the rod and adjustment accordingly.

[0038] In one embodiment, the dosage indicator assembly (alternatively, the exhalation tracker assembly) may be made of five injection-molded and / or extruded parts: the piston, the channel top / cover, the channel base (which may be integrated with the chamber body), the front cover / valve seat, and the channel valve. The front cover subassembly may be made of two or more different parts.

[0039] The valve housing 420 includes a front cover 440 disposed on the front of the channel to prevent the piston from falling off during use. The front cover 440 includes and can define a valve seat 423. The front cover 440 may include a pair of arms 442 that define guides and are slidably engaged with tracks 450 on the valve holder 446. These arms 442 include upright pivot members 448 that engage the valve 430 and apply a preload. The valve holder holds the valve in a predetermined position and enables the valve to throttle the air flow through the fluid channel according to the pMDI used in the chamber. The front cover 440 can include an opening 424 that allows air to flow into the channel. The preload arm or pivot 448 biases the valve 430, configured as a flap in one embodiment, slightly towards the opening 424. The front cover and the valve seat can be made of various materials such as metal or plastic screens.

[0040] In one embodiment, the valve 430 is configured as a thin flexible flap and is offset from the valve seat in the normal open position. When the patient inhales, the air flow increases through the gap between the valve and the valve seat. Depending on the age group and pMDI used, the valve closes partially or completely against the valve seat, restricting the air flow to the fluid channel. Even in the fully closed position, in embodiments, the valve may not completely prevent the air flow through the inlet. For example, a gap may be left, or various leak openings may be provided to maintain some minimal air flow. Although a flap embodiment is shown, the valve can also be configured as a duckbill valve, a ball valve, an umbrella valve, etc.

[0041] As shown in FIGS. 29, 32, and 33, the positioning of the fulcrum 448 preloads the valve flap into a specific angular range (B) and maintains a specific valve seat length (A) (see FIG. 29) according to the user age range. As shown in Table 1 below, the fulcrum 448 and / or the seat 432 can be configured to provide various valve angles and valve seat lengths. It should be understood that other angles and lengths outside the provided ranges can also be suitable depending on other design factors including, but not limited to, the valve configuration, dimensions, and materials.

[0042] Table 1: Valve Settings TIFF2025516831000003.tif34155

[0043] In one embodiment, the valve 430 and the valve seat 432 can be fixed for a specific user target, such as a specific age group. In other embodiments, the valve assembly may be adjustable. In an embodiment, a one-time adjustment is performed including positioning the valve 430, the valve seat 432, the inlet opening, and / or another feature (e.g., the fulcrum 448) to allow for a change in the airflow through the channel during assembly or during the patient's first use. As a result, the valve will operate according to the desired specifications without the need for valve seat components specific to each age range. For example, as shown in FIG. 33, the fulcrum 448 can be made an extension 448 by, for example, a telescoping support so that the height of the arm extending from the support or the distance between the arm defining the fulcrum and the valve seat can be adjusted. Alternatively, or in combination with the adjustability of the fulcrum, the position of the valve seat and thus the defined opening can be adjusted or moved relative to the inlet of the fluid channel, or conversely, the inlet can be moved or its size adjusted to increase or decrease the passage between the ambient environment and the fluid channel or the size of the proximal opening / inlet (see FIG. 33).

[0044] Thus, in one embodiment, the valve assembly includes a valve 430 disposed adjacent to the inlet of the fluid channel, and the valve is movable from a normal open position to an inhalation position in response to inhalation by the user. When the valve moves to the inhalation position, it at least partially closes the inlet opening. The valve assembly includes a pivot member 448 that biases the valve to the normal open position, i.e., a member that applies a preload to the valve. The valve assembly is adjustable among a plurality of settings to vary the flow rate within the fluid channel.

[0045] In any embodiment, during operation, the user 148 holds the chamber in a horizontal position so that gravity does not play an unintended role in the movement of the turbine 170 or piston 270 or the resistance thereto. In the embodiments of FIGS. 9 and 10, to prevent inadvertent movement of the turbine, the dip 182 in the track prevents rolling of the turbine 170 due to the chamber inadvertently tilting during setup at an angle α, for example, between 0 degrees and 20 degrees and including that angle. The dip 182 is disposed adjacent to the dosage indicator 160 and is disposed downstream or immediately downstream of the dosage indicator 160, for example, when the dosage indicator is in the pre-inhalation position. The dip 182 can be designed as a concave curvature in the track, channel, and rack. In this embodiment, the channel and track are curved. Even with the dip, the entire track is in the same plane defined, for example, by the X and Y directions. The system is calibrated such that the gravity that the turbine 170 must overcome to climb out of the depression 182 is incorporated into the overall design so that the turbine reaches the administration completion position when the drug has been fully administered.

[0046] In other embodiments, the fluid channel and track are not linear but rather may follow a curved or serpentine path, for example, a circular path that may be located in a horizontal plane. For example, the flow indicator may follow a circular path where the pre-inhalation position and the competing administration position are adjacent.

[0047] The tidal volume and the maximum inhalation speed vary among different age groups, being lowest in infants and highest in adults. Ideally, turbines 170 and pistons 270 should have high sensitivity to inhalation (<7 L / min) for all age groups. However, high sensitivity, for example when integrally formed with the holding chamber, may limit the length of the fluid channel, which could cause the turbine to move too quickly to the distal end of the fluid channel or the administration completion position. In one embodiment, the adult turbine fluid channels 150, 250 can be made much longer (~2 - 3 times) assuming that the resistance due to the increased channel length is not too high, so as to detect a very low inhalation rate (<7 L / min). By varying the turbine sensitivity, turbines 170 and pistons 270 can be optimized to function for the correct inhaler volumes of three different patient groups. The weight of the turbine can also be reduced for increased sensitivity. For example, in one embodiment, the turbine blades 186 can be thinned and the diameter of the fins can be reduced. Overall, it is desirable to lower the moment of inertia for increased sensitivity. If the diameter of the turbine blade exceeds 12 mm, the fins require more material, the weight decreases, and the sensitivity may be reduced.

[0048] The movement of the turbine is highly sensitive to the airflow because the turbine is very lightweight. Also, the design of the rack 206 and pinion 188 causes the turbine 170 to roll at a constant rotational distance speed, so the friction that limits the movement of the turbine is minimal. In other embodiments, the dose indicator can slide within the track, and the associated friction provides resistance.

[0049] Air passing through the fluid channel from inlet 152 to outlet 154 rotates turbine 170 and translates within fluid channel 150. Since turbine 170 contacts the fluid channel via pinion 188, the turbine moves along the fluid channel at a speed much lower than the linear speed at the tip of turbine blades 186. In an embodiment, a smaller diameter pinion 188 rotates the turbine a greater number of times to travel the distance of the waterway, thus enabling design control of the turbine response. As shown in FIG. 12, a gap (G1) or clearance less than the depth of teeth 190, 207 of the pinion and / or rack is provided between the outer peripheral surface 230 of the pinion gear, or the upper surface, and the upper surface 202 of the track, or slot. This clearance or gap (G1) ensures that the turbine pinion 188 remains engaged with the rack 206 during use and transport, while avoiding frictional engagement between the pinion gear 188 and the upper surface 202 of the track. To prevent turbine blade 186 from hitting and engaging the sidewall 240 of the channel, the gap (G2) between the end wall of the shaft and the sidewall of the track is smaller than the gap (G3) between the sidewall 240 of the channel and turbine blade 186.

[0050] The main source of drug delivery feedback is when the user visually observes or sees, for example, turbine 170 or piston 270 move to and stop at the end of the track or fluid channel 150. Turbine 170 or piston 270 can be made from a colored (not transparent or white) plastic (e.g., black, red, green, orange, blue, etc.) to provide contrast to the user, so that the user's eye does not need to focus on the characteristics of the turbine, but rather can see objects of different colors. The turbine material or piston material may be mixed with a light-emitting additive in the dark or may be coated with a light-emitting coating in the dark, so that the caregiver or user can see turbine 170 or piston 270 move when administering the drug in the dark.

[0051] Another feedback source is derived from the sound generated when the pinion tooth 190 rolls over the rack tooth 207 as the turbine 170 moves along the fluid channel 150. Thus, indicating that the dosage indicator 160 is translatable includes listening for the translation of the dosage indicator in the fluid channel when the dosage indicator rotates. Thus, the term "observing" refers to seeing or hearing. Since the turbine makes a subtle rattling sound, whether the turbine is moving is indicated to the user by the sound. Further, when the turbine hits the end of the fluid channel, for example engages the stop 212 and thereby reaches the dosage completion position, the turbine 170 provides another audible cue to the user / caregiver indicating the reached position.

[0052] In one embodiment, the dosage indicator assembly includes a plurality (shown as four) of components, each of which can be injection molded into the turbine 170, the fluid channel top / cover 261, the channel base 262, and the front cover 264. The fluid channel upper / cover and bottom / base can be joined, for example, by snap fit or slip fit / interface and / or by an adhesive. Each of the upper and lower surfaces includes a horizontal wall that defines one of the upper and lower surfaces 202, 204 of the track. In another embodiment, the fluid channel component can include a pair of side components. The base component defines the lower half of the fluid channel including the track and the rack teeth. The base component can be separate from or integral with the chamber body. If separate, the base component can be joined to the chamber body by an insert portion / guide portion, a tab, an adhesive, or other fastener. When the assembly is complete, the cover and base define the fluid channel. In one embodiment, the fluid channel can be, for example, an integral one made from an extruded product, with caps disposed at its opposing ends.

[0053] After the turbine 170 is disposed within the fluid channel, a front cover 264 may be disposed and secured to cover the front face of the fluid channel in order to prevent the turbine 170 from falling off. The front cover 264 may have holes that allow for the flow of air into the turbine channel and define the inlet 152. The front cover can be made of various materials, such as a metal or plastic screen. In this way, the front cover maintains the turbine 170 within the fluid channel such that the turbine does not pose a risk of suffocation. The fluid channel 150 is removable from the chamber body, and the chamber body can be easily cleaned. The fluid channel has an outlet 154 that mates / communicates with an inlet 156 that communicates with the holding chamber.

[0054] The fluid channel assembly, and particularly the top cover, may be made of a transparent or translucent material such as polypropylene (PP) plastic (or in some cases other polyolefins, nylon, MABS, polycarbonate) so that the user can see the turbine moving along the length of the fluid channel. As previously mentioned, the turbine 170 can be a color that contrasts with the color of the holding chamber and the fluid channel (e.g., black or a bright color). Since the sensitivity of the turbine depends on the weight, a lightweight plastic such as PP can result in a higher sensitivity of the turbine than if it were made of a high-density plastic such as PET.

[0055] The turbine 170 includes a shaft 184 configured to have a pair of pinion gears 188 at opposing ends that define a rotational axis 189 that extends in a lateral direction perpendicular to the longitudinally extending fluid channel and track. A plurality of bifurcated fin blades 186 extend radially outwardly from the shaft 184 and are arranged in a Savonius (drag) design (e.g., straight fins, helical fins, cup design). In one embodiment, the turbine 170 is configured with five blades 186. In other embodiments, it can be configured with three to eight blades or anywhere in between.

[0056] The effective turbine diameter (the distance across or between the tips of the fins as seen along the axis of the turbine, or the diameter of the space filled by the rotating turbine) is 8.6 mm, 7.2 mm, and 6.6 mm for adult, child, and infant turbines, respectively, but may be varied by 1 - 2 mm each. The turbine diameter determines the length of the blade / fins, which affects the weight of the turbine and its sensitivity to the airflow. The weights of the adult, child, and infant turbines can be 0.077 g, 0.046 g, and 0.033 g, respectively, but can be up to 0.125 g, for example, if suitable for adults. The thickness of the turbine blade / fins can be varied to increase or decrease the weight of the turbine and thus affect its sensitivity. The thickness of the blade / fins for adults or infants can be between 0.1 mm and 0.6 mm. In various embodiments, the thickness of the adult blade / fins is 0.35 mm, for children is 0.25 mm, and for infants is 0.20 mm. In adult, child, and infant designs, the blade / fins can have a radius of curvature between 2 mm and 6.5 mm, with 2.5 mm being preferred.

[0057] The shaft 184 extends beyond the length of the blade 186 and is formed in the shape of a pinion 188. In one embodiment, the length of the shaft or pinion is about 2.5 mm, which can be selected based on the balance of added weight and friction as the length of the turbine increases. The length of the pinion can be between 0.5 mm and 5 mm.

[0058] The pinion 188 can have various numbers of teeth 190, for example, between 4 and 7 teeth, and in one embodiment, 5 teeth are preferred. More teeth may help prevent the turbine from popping out of the track. The diameter of the pinion, or the outer circumference of the pinion gear 188 and the teeth 190, can be between 0.5 mm and 2.5 mm, and in various embodiments, can have a diameter between 1 mm and 1.75 mm, which provides an appropriate ratio between the diameter of the outer fins and the diameter of the pinion. In one embodiment, the pinion gear has a diameter of 1.75 mm.

[0059] The profile of the outer surface 276 of the fluid channel may be rounded for aesthetics and to improve the tactile feel and cleanability. To maximize the space within the curved fluid channel, the turbine 170 has a profile that is rounded when viewed perpendicular to the turbine axis, maintaining a uniform clearance from the fluid channel. The length and cross-sectional shape of the fluid channel 150 are formed to conform to the shape of the turbine, but a 0.5 mm gap is left between the blades and the inner surface of the fluid channel 150 to prevent contact. The opening 152, or inlet, connecting the fluid channel to the chamber minimizes the resistance to the flow of air between the fluid channel and the chamber. In one embodiment, the opening 152 is 10 mm × 9 mm, but the opening can be smaller or larger.

[0060] During operation, a method of dispensing a medicament includes dispensing a metered dose of aerosolized medicament into the internal volume 110 of the chamber housing, for example, by actuating an inhaler 106, the medicament being dispensed from a predetermined metered inhaler. The medicament may be discharged into the holding chamber while the interface is engaged with the patient or pre-discharged. The method includes inhaling through a user interface 104 coupled to the chamber housing, thereby drawing a metered dose of aerosolized medicament out of the internal volume, advancing dose indicators 160, 260 within fluid channels 150, 250 in fluid communication with the chamber housing from an inhalation prior position to an administration complete position as shown in FIGS. 7A - C and 25, observing the advancement of dose indicators 160, 260, and ceasing inhalation when dose indicators 160, 260 reach the administration complete position. Air is drawn into the holding chamber by an airflow from one or more inlets depending on the resistance and size of the variable size opening as the medicament is inhaled. Advancing the dose indicator includes rotating a turbine in one embodiment. Appropriate inhaler medicament delivery through the holding chamber 102 may require an adult to inhale 500 mL, a child to inhale 300 mL, and an infant to inhale 50 mL. The inhaler system approximates the inhalation volume to the inhalation rate.

[0061] The flow rate designed to cause the turbine 170 or piston 270 to begin moving is referred to as the "trigger flow rate". This flow rate can be 5 - 30 L / min for adults, 5 - 20 L / min for children, and 5 - 10 L / min for infants, but ideally 15 L / min, 10 L / min, and 5 L / min respectively. Weight, pinion diameter, channel length, channel cross-sectional area, back piece valve hole size, and various other characteristics can affect the trigger flow rate of the turbine. In one embodiment, the holding chamber has three inlets through a channel, an inhaler / receptacle, and a valve. For each age variation design (adult, child, infant), the turbine and channel are designed to begin moving at a predetermined pressure based on the average tidal breathing flow rate.

[0062] In an alternative embodiment, the sliding dial 300 aligns with various dial numbers, or indicators 304, to vary the size of the opening 302 that defines an inlet within the back piece 114. For example, the indicators can be configured as alphanumeric such as letters, numbers, etc., and / or as other shapes or symbols that can be identified by different colors. Prior to use, the user uses the indicator 304 to set the dial 300 to the corresponding inhaler setting. The inhaler settings can be those associated with the inhaler device, device or instructions, and may be described online. At the adult trigger flow rate, the dial opening 302, or inlet 220, has a split flow rate of 12 L / min at setting 3 (maximum setting, fully open), a flow rate of 8 L / min at setting 2 (intermediate setting, partially open), and 0 L / min at setting 1. In the embodiments shown in FIGS. 23A - C, three settings are configured, although more settings can provide more resolution and improved exhalation tracker accuracy. In other embodiments, it can have settings between and including 2 and 20 settings, or between and including 5 and 10 settings.

[0063] In other embodiments, a smartphone or computer camera can take a video of the movement of the breath tracker feature to provide real - time feedback on drug delivery performance through a user interface such as a smartphone or tablet via Bluetooth®. Alternatively, a controller incorporating various sensors and software can detect the type of inhaler being used and track the change in position of the exhalation tracker piston over time for a channel. From this information, various performance metrics can be calculated, including peak inhalation rate, inhalation volume, the inhaler before actuator activation, and the posture of the neck and head during treatment. The controller and output can then provide hints to improve the user's inhalation technique for subsequent treatments.

[0064] In the case of a pediatric chamber and a toddler chamber, the user interface can provide or incorporate a story or an interactive game that requires the user to complete the story by moving a breathing tracker over the full length of the channel using an inhaler and the chamber. For example, an interactive story can be viewed through a virtual reality headset, and augmented reality can integrate the use of the chamber and the story.

[0065] Although the present invention has been described by way of example in its preferred embodiments, those skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the invention. Therefore, the foregoing detailed description is to be considered illustrative rather than limiting, and it is intended that the scope of the invention be defined by the appended claims, which include all equivalents.

Explanation of Reference Numerals

[0066] 100 Aerosol delivery system 102 Holding chamber 104 Interface 106 pMDI canister 107 Rear end 108 Chamber housing 110 Internal volume 112 Outlet 115 Exhalation valve 116 Inlet 118 Mouthpiece 120 Receptacle 132 Inhalation valve

Claims

1. A drug delivery system, A chamber housing that defines an internal volume, comprising an inlet adapted to receive a certain dose of drug and an outlet spaced apart from the inlet, wherein the inlet and the outlet are in fluid communication with the internal volume, The internal volume and the fluid channel that is in fluid communication with it, A dosage indicator that is translationally translatable within a fluid channel from a pre-inhalation position to a completed administration position, wherein the position of the dosage indicator at the completed administration position indicates the completed administration of the dose of drug through the outlet, and the dosage indicator is visible through the fluid channel as the dosage indicator translates between the pre-inhalation position and the completed administration position. Equipped with, A drug delivery system comprising a rod positioned within a fluid channel, wherein the dosage indicator includes a piston that slides along the rod from a pre-inhalation position to a completed-administration position.

2. The drug delivery system according to claim 1, wherein the dose indicator is translatable along a linear path between the pre-inhalation position and the completed administration position.

3. The drug delivery system according to claim 1, further comprising a user interface coupled to the chamber housing, wherein the dose indicator is closer to the user interface at the pre-inhalation position than at the administration completion position.

4. The drug delivery system according to claim 1, wherein the fluid channel comprises a track, and the piston is movable along the track between the pre-inhalation position and the completed administration position.

5. The drug delivery system according to claim 1, further comprising an auditory indicator adapted to provide an audible signal when the dose indicator is translated to the administration completion position.

6. The drug delivery system according to claim 5, wherein the dosage indicator comprises an auditory indicator.

7. The drug delivery system according to claim 1, further comprising an adapter coupled to the chamber housing, wherein the inlet comprises a first inlet determined by the adapter, and the adapter further comprises a second inlet communicating with the internal volume, wherein the second inlet comprises a variable-size opening.

8. The drug delivery system according to claim 7, wherein the variable-size opening is determined by a one-way inhalation valve positioned above the second inlet.

9. The drug delivery system according to claim 7, wherein the variable-size opening is determined by a dial that is movable relative to the second entrance.

10. The drug delivery system according to claim 7, wherein the fluid channel is in fluid communication with the internal volume at a third inlet located at a distance from the first and second inlets.

11. The drug delivery system according to claim 1, wherein the inlet and outlet are spaced apart in the longitudinal direction, and the fluid channel extends in the longitudinal direction.

12. The drug delivery system according to claim 1, wherein the fluid channel comprises an inlet opening and an outlet opening that are in fluid communication with the internal volume, and further comprises a valve assembly having a valve disposed adjacent to the inlet opening of the fluid channel, wherein the valve is movable from a normally open position to an inhalation position in response to inhalation by a user.

13. The drug delivery system according to claim 12, wherein the valve at least partially closes the inlet opening when it moves to the inhalation position.

14. The drug delivery system according to claim 12, further comprising a pivot member that biases the valve to the normally open position.

15. The drug delivery system according to claim 12, wherein the valve assembly is adjustable between a plurality of settings to change the flow in the fluid channel.

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