JP4616002B2 - Respiratory aerosol dispensing device - Google Patents

Description

  The present invention relates to a respiratory activatable drug dispensing device in which a metered amount of drug is administered to the respiratory system in response to patient inhalation.

  A commonly used means for dispensing aerosol from an aerosol container is a metered valve. The metered valve is particularly useful for administering pharmaceutical formulations that contain a liquefied gas propellant and are delivered to the patient by aerosol.

  In some metering valves, the metering chamber is filled with the pharmaceutical formulation before the patient releases the dose by actuating the valve stem. After dispensing a single dose, the metering chamber is refilled with the formulation so that the metering valve is ready to release the next dose. As a result, the metering chamber always contains the formulation except for a short time when the user presses the valve stem to release the dose.

  Another metering valve is designed such that the metering chamber does not substantially function when and until the valve stem is not actuated. An example of such a valve is disclosed in US Pat. No. 4,819,834. The operation of such a valve stem can be divided into a filling phase and a draining phase. The filling phase begins when the valve stem is pushed in during operation. Pushing the valve stem creates a temporary metering chamber that is in fluid communication with the remaining metering volume defined by a small annular gap. As the valve stem is pushed in, the temporary portion of the metering chamber expands and the formulation enters the metering chamber. As valve stem displacement continues, a stage is reached where filling of the temporary metering chamber stops.

  Eventually, the displacement of the valve stem through which the metered dose is discharged continues until the discharge phase. With these valves, the formulation is then expelled to the patient after the temporary metering chamber is rapidly filled in a single operation. In general, metered doses do not exist in the metering chamber of these metering valves for a sensitive time.

  A metering valve with a temporary metering chamber has advantages over other types of metering valves for delivering aerosol formulations, but the formulation flow from the container to the metering chamber may be disturbed or impeded Is now known. Flow through a significantly limited access area, such as a narrow annular passage and / or access path to the metering chamber, may be hindered enough to substantially incompletely fill the metering chamber. is there. When this happens, an inconsistent or inaccurate volume of the formulation may be delivered. In particular, it has now been found that the time that can be used to fill the metering chamber also significantly affects the ability to completely fill the temporary metering chamber. The time available for filling depends on the speed at which the valve stem is pushed. In so-called “press and breathe” devices in which the patient manually pushes the aerosol container against the valve stem and fires the valve, the speed at which the valve stem is pushed is typically 100 mm / second or less. However, breath-actuated inhalers typically fire valves faster than manual firings, for example, valve stem speeds range from 165 to 330 mm / sec. Thus, it is difficult to use a metering valve having a temporary metering chamber with a breath-actuated device.

  A feature common to many of the known breath actuated devices is that it involves two stages of work. That is, it includes a preparatory stage in which a preparatory force is applied to the valve stem but the operation of the valve stem is prevented, and a firing stage in which the preparatory force is released and the valve stem moves to fire the valve. The preparation phase is generally a manual operation and can include movement that moves the valve stem to some extent but not enough to fire the valve. All movements of the valve stem during the preparation phase tend to be relatively slow. When the device is started by inhalation, the valve stem is displaced at high speed under a preparatory force.

  If the metering and firing phase of the type of metering valve with a temporary metering chamber occurs simultaneously with the preparation and firing phase of the breath-actuated device, any difficulties or problems associated with the flow of the formulation filling the metering chamber will be overcome It has now been found that there is a possibility of being at least significantly reduced.

Therefore, according to the present invention,
An aerosol container containing a pressurized drug formulation with a metered dose valve having a movable valve stem;
A housing disposed around the aerosol container;
A patient port in communication with the dispensing valve;
Provision means configured to bias the valve stem relative to the aerosol container sufficient to move the valve stem and fire the valve;
Restraining means movable between a blocking position that prevents the valve from firing by biasing and a release position that can fire the valve by biasing;
Trigger means for moving the suppression means from the blocking position to the release position in response to inhalation through the patient port;
A breath-actuated drug dispensing device comprising:
In this device, this aerosol valve is
A valve housing;
A tank element arranged in the valve housing;
A valve stem mounted within the valve housing and tank element and continuously movable between a first position, a second position and a third position when the valve stem is pushed in a single direction; Including
When the valve stem moves from the first position to the second position, a metering chamber is formed and defined between the valve stem and the tank element, and the formulation flows from the aerosol container into the metering chamber;
In the second position, the metering chamber is sealed from the aerosol container with a predetermined volume;
In the third position, the formulation is released from the metering chamber through the valve stem,
The preparation means is configured such that when the drug dispensing device is prepared by actuating the preparation means, the valve stem can move from its first position to its second position to form and fill the metering chamber. And placed
The restraining means is constructed and arranged to maintain the valve stem in the second position in the blocking position until the triggering means is activated by inhalation through the patient port.

  The present invention fills the metering chamber of an aerosol valve of the type having a temporary metering chamber by controlling the movement of the valve stem from the first position to the second position by means of preparation and suppression of the breath actuated device. It provides an easy and effective means of overcoming the problems associated with doing so. Once the breath actuated device is prepared, the valve stem is held in the second position and the metering chamber is completely filled with the preparation and ready to be dispensed. The preparatory phase of the breath actuated device is slow enough that it can be filled when the metering chamber is created by movement of the valve stem.

  The present invention is applicable to various breath actuated devices including those in which the restraining means includes a latch mechanism and those in which the restraining means includes means for applying a resistive air pressure.

  In general, the aerosol container will be mounted on a dispensing device with the valve stem positioned in a fixed nozzle block. A preparatory force is applied to the bottom surface of the aerosol container, for example by compression of a spring. By compressing the spring, for example, when the device is prepared by moving the lever to a position beyond the center, the aerosol container moves against the valve stem and the valve stem is partially pushed, after which the restraining means is Engage to prevent further movement. The device is arranged so that this initial movement of the valve stem relative to the aerosol container is sufficient to form and completely fill the metering chamber within the valve. The valve is held in this second position until the patient operates the device by inhaling through the patient port. The trigger is activated by the patient's inhalation, so that the restraining means moves to the release position so that the valve stem and the aerosol container can move relative to each other under the influence of the bias, causing the valve to fire. become.

  In another embodiment of the present invention, an aerosol container is secured within the housing and a preparatory force is applied to a valve stem, eg, a movable nozzle block mounted on the valve stem.

  The present invention will now be described with reference to the accompanying drawings.

  The invention will be described with reference to a breath actuated device as described in EP 0 147 028. However, the present invention includes British Patent No. 1288971, British Patent No. 1297993, British Patent No. 1335378, British Patent No. 1383762, British Patent No. 1392192, British Patent No. No. 143285, WO85 / 01880 pamphlet, British Patent No. 2207799, US Pat. No. 4,803,978, European Patent No. 0186280, British Patent No. 1269554, It will be appreciated that a variety of other breath-actuated devices can be used such as those described in US Pat. No. 5,447,150 and WO 01/93933.

  In the drawings, like reference numerals represent like parts.

  FIG. 1A depicts a cross-sectional view of a breath actuated device in a stationary state. The device comprises an aerosol container (2) containing a pressurized drug formulation and equipped with a dispensing valve (4) having a movable valve stem (6). The housing (8) is disposed around the aerosol container (2) and includes a mouthpiece cover (16) covering the sleeve (10), body (12), top (14), and patient port (18). . The valve stem (6) is positioned in a nozzle block (20) that directs the formulation from the valve stem to the patient port (18).

  The preparation means includes a preparation lever (22) that is pivotally mounted about an axis (23) and acts on a preparation spring (24) secured in the cage (26). In the rest position shown in FIG. 1A, the preparation spring (24) exerts little or no bias on the aerosol container (2).

  The restraining means includes a rocker or rocker (28) pivotably mounted about the shaft (30). One end of the rocker is attached to a tension spring (32) and the other end is pivotally connected to a fastener (34). The other end of the fastener (34) abuts on the cam surface of the blade (36) that acts as a trigger mechanism. The blade (36) is pivotally mounted on the shaft (38).

  In the rest position shown in FIG. 1B, there is a gap (40) between the upper surface (42) of the rocker (28) and the lower surface (44) of the valve ferrule.

  FIG. 1C is an enlargement compared to FIG. 1A and shows a cross-sectional view through the aerosol valve in a first position when the device is in a rest position as shown in FIG. 1A.

  The valve (4) includes a valve housing (46), a tank component (48) positioned within the valve housing, and a valve stem (6) mounted within the valve housing and tank component. The valve includes an outer seal (50) and an inner seal (52). The valve stem (6) is urged toward the first position shown in FIG. 1C by the compression spring (54) held in the spring holding sleeve (56).

  The outer portion of the valve stem (6) includes a discharge passage (58) and a side through hole (60). The inner portion of the valve stem is shaped to completely fill the tank component (48) when the valve stem is in the first position. The inner portion of the valve stem is hollow and in communication with the aerosol container and includes a sampling port (62). When the valve stem is in the first position shown in FIG. 1C, the metering chamber is not formed.

  2A and 2B show the device in the ready position. When the preparation lever (22) pivots upward, the spring (24) is compressed and the aerosol container (2) is biased. The aerosol container moves downward under the influence of a bias until the lower surface (44) of the valve ferrule contacts the upper surface (42) of the rocker (28). The rocker (28) cannot pivot because it is blocked by the fastener (34) engaging the vane (36). During the preparatory work, the aerosol container moves by the distance of the gap (40) shown in FIG. 1B.

  During the preparatory work, the valve moves from the first position shown in FIG. 1C to the second position shown in FIG. 2C. A metering chamber (64) is formed between the inner portion of the valve stem (6) and the tank component (48) as the valve stem moves from the first position to the second position. The metering chamber passes from the aerosol container through the sampling port (62) and through a small annular gap (not shown) between the inner portion of the valve stem (6) and the tank component (48), the metering chamber (64). ) Filled with the formulation. The formulation is prevented from exiting the metering chamber (64) by an outer seal (50) that sealingly engages between the valve stem and tank component (48) and the valve housing (46). In the second position of the valve stem shown in FIG. 2, the inner seal (52) prevents the formulation from passing through the sampling port (62) by sealingly engaging the valve stem. In the second position of the valve stem shown in FIG. 2C, the metering chamber is completely formed and completely filled with the formulation.

  FIG. 3A shows the device in the fired position. Upon inhalation through the patient port (18), the vanes (36) pivot upward. As the blade (36) moves, the end of the fastener (34) is displaced from the blade, thereby moving the locker (28) restraint. The rocker (28) pivots due to the force exerted by the valve fleur under the influence of the preparatory spring (24), thereby allowing the aerosol container (2) to move downward and allow the valve to fire.

  FIG. 3B shows the valve in a firing position. The valve stem (6) is positioned so that the contents of the metering chamber pass through the side through hole (60) and the discharge passage (58) by passing the side through hole (60) through the outer seal (50). Move in the direction. The inner seal (52) remains in sealing engagement with the inner portion of the valve stem and prevents communication between the metering chamber (64) and the aerosol container.

  The rate of movement during firing, i.e., the rate at which the valve stem moves from the second position to the third position, does not affect the performance of the valve because the metering chamber is formed and fully filled in the preparation stage. It will be understood. Thus, high speed movement under the influence of a preparatory spring during a firing operation does not affect the volume of drug dispensed.

  It will be understood that the particular embodiments according to the invention have been disclosed by way of illustration only and that the invention extends to modifications, variations and improvements thereof.

1 is a vertical sectional view representing an embodiment in a first position of a dispensing device according to the invention. It is a figure which shows the suppression means and trigger means of an apparatus. It is sectional drawing of the aerosol valve in a 1st position. FIG. 1B is a view similar to FIG. 1A, with the device in the ready position and the aerosol valve in the second position. FIG. 1B is a view similar to FIG. 1B, with the device in the ready position and the aerosol valve in the second position. FIG. 1C is a view similar to FIG. 1C, with the device in the ready position and the aerosol valve in the second position. FIG. 2 shows the device of FIG. 1 in a first position. It is a figure which shows the aerosol valve | bulb of the 3rd (launch) position.

Claims (6)

An aerosol container containing a pressurized drug formulation with a metered dose valve having a movable valve stem;
A housing disposed around the aerosol container;
A patient port in communication with the metering valve;
Provision means configured to bias the valve stem against the aerosol container sufficient to move the valve stem and fire the metering valve;
Restraining means movable between a blocking position for preventing the metering dispensing valve from firing by the biasing and a release position capable of firing the metering dispensing valve by the biasing;
Trigger means for moving the suppression means from its blocking position to its release position in response to inhalation through the patient port;
A breath-actuated drug dispensing device comprising:
The metering valve is
A valve housing;
A tank element disposed in the valve housing;
A valve stem mounted within the valve housing and tank element and continuously movable between a first position, a second position and a third position when pushed in a single direction. ,
When the valve stem moves from the first position toward the second position, a metering chamber is formed and defined between the valve stem and a tank element, and from the aerosol container into the metering chamber The formulation flows,
In the second position, the metering chamber is sealed from the aerosol container with a predetermined volume;
In the third position, the formulation is released from the metering chamber through the valve stem;
The valve stem moves from its first position to a second position when the drug dispensing device is prepared by actuating the preparation means, so that the metering chamber can be formed and filled Preparation means are constructed and arranged,
A breath-actuated medicament configured and arranged to maintain the valve stem in the second position in the blocking position until the trigger means is activated by inhalation through the patient port Dispensing device.   The respiratory activatable drug dispensing device according to claim 1, wherein the preparation means includes a spring.   The respiratory activatable drug dispensing device according to any one of claims 1 and 2, wherein the valve stem is disposed in a nozzle block and the preparation means biases the aerosol container.   The respiratory activatable drug dispensing device according to any one of claims 1 to 3, wherein the suppressing means includes a latch, and the trigger means includes a blade.   The respiratory activatable drug dispensing device according to claim 4, wherein the vanes are disposed within the patient port.   The respiratory activatable drug dispensing device according to any one of claims 1 to 3, wherein the suppressing means includes means for applying a resistance air pressure so as not to fire the metering dispensing valve under the influence of the preparing means.

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