Description The invention relates to a delivery device for products, such as medicaments, and particularly to a device for transferring to the portal regions of the respiratory tract of a patient a metered dose of a product contained in a pressurised dispensing container.

It has been demonstrated that there can be significant therapeutic benefits through the delivery of medicaments to the portal regions of the respiratory tract. These portal regions include the nasal, sub-lingual, buccal and oesophageal regions of the respiratory tract. It has further been demonstrated that there are numerous user benefits from the use of pressurised metered dose dispensing containers for the delivery of aerosolised medication on a regular basis. These benefits may include but are not limited to portability, ease of use and product stability.

The technology of pressurised metered dose dispensing containers has been well characterised and published and it is accepted that typically these systems perform more reliably if operated in a generally vertical orientation with the valve directly filling from the contents at the lowest point of the container. In order to administer a therapeutic dose to one of the portal regions of the respiratory tract the direction of the emitted aerosol has to have a component substantially perpendicular to the container axis. The majority of pressurised metered dose dispensing containers currently used are for delivery or aerosolised medication to the lungs, the translation of direction is achieved through the use of an exit orifice angled towards the patients mouth. Due to geometric restrictions this orifice is typically in close proximity to the exit from the metering valve. Typically for inhalation products the device has a mouthpiece section of substantial size to fit the patients mouth. In this arrangement deposition of drug on the mouthpiece is typically in the order of 10% to 20%. In ordet to access the nasal and sub lingual regions and achieve targeted delivery this mouthpiece geometry is far too large and if only simple scaling is conducted deposition figures of 40%-50% may be achieved.

One approach that has been considered to alleviate the aforementioned problems is to increase the distance from the valve stem exit to the aerosol exit orifice. However, due to manufacturing constraints this can result in a significant increase in the connecting volume between the valve stem exit to the aerosol exit orifice resulting in un-satisfactory spray characteristics and significant deposition. Another technique is to reduce the volume by creating a flow path between two communicating components by providing the mouthpiece with an insert. However this presents the inherent risk that any small inserted component may become dislodged from the device when a patient inhales and thereby become trapped in the patient.

Examples of products developed for liquid nasal administration, where it is important to minimise the volume in the flow path of pump based systems that contain no volatile propellants, are known. One such example is disclosed in WO00/00736. Typically in these applications the product contains no volatile liquefied propellant and the dispensing pump orientation is normally aligned with the angle of administration allowing simple in line construction of the actuating means. This orientation will adversely impact on the performance of pressurised metered dose dispensing containers and is therefore not an acceptable solution where accurate delivery of medication is required. To address issues of atomisation of aerosols with a high proportion of non-volatile component in the formulation, GB 2,312,379 discloses a method of the incorporation of a mechanical break up insert into a conventional inhalation actuator geometry. The flow path length from the exit from the valve to the orifice is still relatively short and is therefore sub- optimal for targeted administration to portal regions of the respiratory tract.

The present invention seeks to provide a delivery device with improved delivery of products to the portal regions of the respiratory tract. According to the present invention, there is provided a delivery device for dispensing a medicament contained in a pressurised dispensing container to a patient, the device comprising a housing having an inlet for the passage of medicament into the device from a pressurised dispensing container releasably attachable to the device, a duct extending from the inlet to define a flow path for the passage of medicament through the device, a nozzle at one end of the duct for the passage of medicament from the device into a patient's airway and, an insert located in the duct to reduce the volume of the flow path, the device being configured to prevent the insert from passing out of the duct into a patient's airway when the device is in use.

In a preferred embodiment, the opposite end of the duct is open to enable insertion, and removal, of the insert into, or from, the duct.

Conveniently, the housing has an aperture therein in the vicinity of the opposite end of the duct for insertion of the insert through the aperture and into the duct.

Preferably, the device includes means to prevent the insert from being inserted into the duct beyond a predetermined point or from passing all the way through the duct.

Advantageously, said means comprises a barrier in the duct which cooperates with the insert to prevent further insertion of the insert into the duct.

An orifice is preferably provided in the barrier for the passage of medicament from the duct into the nozzle.

The insert advantageously includes a cap which engages the opposite end of the duct when fully inserted into the duct to prevent further insertion of the insert into the duct.

In a preferred embodiment, the flow path is formed between the wall of the duct and the surface of the insert. Most preferably, the insert is shaped so as to form a substantially fluid impervious seal with the wall of the duct over a substantial proportion of its surface.

In one embodiment, the insert is longer than the length of the flow path. In this case, if the flow path is formed in the insert, then it does not extend for the entire length of the insert but extends for only a portion of its length and the medicament expelled from the pressurised dispensing container through the inlet of the device meets the insert side-on or at an angle to the longitudinal axis of the insert as it enters the flow path. A part of the insert may be configured so as to completely block the duct to prevent the backflow of air or medicament along and out of the duct, other than through the nozzle once it has travelled along the flow path.

Preferably, a groove is formed in the surface of the insert and extends longitudinally for a significant proportion of its length to form the flow path for medicament between the inlet and the nozzle.

In addition or alternatively to a groove in the surface of the insert, a channel is preferably formed in the wall of the duct and extends longitudinally for a significant proportion of its length to form the flow path for medicament between the inlet and the nozzle.

The duct may be angled with respect to the direction in which the medicament enters the duct through the inlet by between 15° and 75°.

In one embodiment, the device may comprise a blade-shaped element on the duct to support the tongue during sub-lingual administration of medicament.

In another embodiment, the delivery device comprises a cover member pivotable with respect to the housing into a position in which it covers the nozzle when the device is not in use. Conveniently, the cover member is pivotally attached to the insert.

In a preferred embodiment, the insert is a snug fit in the duct. Pieferably the device may be used to target delivery to the sub-lingual, nasal, buccal and oesophageal regions of the respiratory tract.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional side elevation of a delivery device according to the invention; Figure 2 is a cross-sectional elevation of an embodiment of the device suitable for sub-lingual administration, showing the positioning of the device relative to the patients mouth; Figure 3 is a rear elevation of a delivery device suitable for sub-lingual administration, showing the location of an inserted component; Figure 4 is an external isometric view of a delivery device suitable for sub -lingual administration, showing the location of the tongue supporting member of the device; Figure 5 is a front lower elevation of a delivery device suitable for sub-lingual administration, with a part section through the nozzle and tongue supporting member, showing the disposition of the flow channel; Figure 6 is an external isometric view of an insert embodiment, showing the location of the flow channel; Figure 7 is a longitudinal vertical sectional view of an insert embodiment, showing the location of the flow channel; Figure 8 is a cross-sectional side elevation of an alternate embodiment of a delivery device according to the invention suitable for sub-lingual administration, incorporating an integral closing member; Figure 9 is a cross-sectional elevation of an alternate embodiment of a delivery device according to the invention suitable for sub-lingual administration incorporating an integral closing member and cover; Figure 10 is a part cross-sectional side elevation of an alternate embodiment of a delivery device according to the invention suitable for sub-lingual administration, showing an alternate method for the creation of a flow path; Figure 11 is a cross-sectional elevation of an embodiment of the device suitable for nasal administration; and Figure 12 is a cross-sectional elevation of an embodiment of the device suitable for nasal administration, showing the positioning of the device relative to the patients nose.

Referring to Figure 1, a delivery device 1 for a medicament comprises a housing 2 for receiving a pressurised dispensing container 3 of the medicament, a nozzle 4 for insertion into the mouth of a user of the device below the tongue and, a tongue supporting member 5. The container housing 2 is profiled so as to guide the pressurised dispensing container 3 and is open at its upper end. The lower portion of the housing 2 includes an annular socket or inlet 6 for receiving the tubular valve stem 7 of the container 3. The socket 6 communicates with a duct 8 formed in the housing 2. The duct 8 extends from the inlet 6 to the nozzle 4 and is typically cylindrical in section.

The housing 2 contains an aperture 10 which facilitates access for both manufacture and assembly purposes. An insert 11 is located in the duct 8 through the end of the duct 8 opposite to the end at which the nozzle 4 is provided. The insert 11 is generally cylindrical and the location of the insert 11 to the duct 8 is such that a liquid secure seal over a significant proportion of the inner surface of the walls of the duct 8 is achieved. The insert may be a snug or interference fit in the duct 8.

The insert 11 is prevented from passing through the duct 8 by a barrier or wall 4a extending radially into the duct 8. An exit orifice 14 is provided in the centre of the wall for the passage of medicament from the duct 8 into the nozzle 4.

The insert 11 has, on its outer surface, a groove 12 running longitudinally for a proportion of the length of the insert 11. The insert 11 is rotationally orientated such that the groove 12 aligns the inlet 6 with the nozzle 4. The groove 12 is in communication with a radial flow path 13 formed in the duct 8 between the end interface of the insert 11 and the wall 4a. The radial flow path 13 communicates the groove 12 with the exit orifice 14. The insert 11 may further contain a relief feature 15 which may be in the form of a longitudinal cavity facilitating manufacture and orientation. It will be appreciated that there is no air flow passage from around the insert 11 apart from along the groove 12, or via the rear aperture 10 through the nozzle 4 into the patient.

Referring to Figure 2, the delivery device 1 is located by the patient such that the nozzle 4 passes over the lower teeth 16 and is located in such a way that the exit orifice 14 is generally directed towards the sub-lingual region of the mouth 17. The tongue is supported and kept clear of the end of the nozzle 4 by the tongue supporting member 5.

Referring to Figures 1 to 7, in use, a patient or user holds the delivery device 1, usually in one hand, and applies his or her mouth to the nozzle piece 4 and the tongue support 5. The delivery device is orientated such that the primary axis of the pressurised dispensing container 3 is tending towards vertical with its metering valve 27 facing downwards. The patient locates the delivery device 1 such that the nozzle 4 passes over the lower teeth 16 and the tongue 18 rests on the tongue supporting member 5.

The container 3 is depressed downwardly on to its stem 7 to release a dose of product from the container 3 via the metering valve 27. The dose of product is projected by the pressure in the container 3 and the evaporation of the liquefied propellant through the inlet 6 and into the flow path 19 created by the groove 12 in the insert 11 and a portion of the cylindrical wall of the chamber 8. The product flows through the flow channel 19 under the influence of the vapour pressure of the liquid propellant and continued evaporative expansion into and through the radial flow path 13 and into and through the orifice 14.

Following administration of the product, the patient releases pressure on the pressurised container 3 which returns to its resting position under the influence of internal spring force in the attached metering valve 27. The above cycle can be repeated a number of times in order to administer larger amounts of product. Referring to Figure 8, an alternate embodiment of the invention disclosed in Figures 1 to 7 incorporates a cap member 20 to close off the aperture 10. In the depicted embodiment the cap member 20 is incorporated directly into the insert component 11. The cap member 20 may also incorporate single or multiple location ribs which may be designed such that they will assist in the location and/or retention of the cap member 20 and insert 11 within the aperture 10.

Referring to Figure 9, an alternative embodiment of the invention disclosed in Figures 1 to 8 incorporates a cap member 20 to close off the aperture 10 and further incorporates a cover member 22. In the depicted embodiment the cap member 20 and the cover member 22 are incorporated directly into the insert component 11. The cover member 22 is attached to the cap member 20 via a flexible hinge arrangement 23 ideally created in the manufacturing process. When in use, the cover member 22 is rotated on the flexible hinge 23 to expose the nozzle 4. Following use, the cover can be rotated back in to position and locates to the profile of the tongue support member 5 thus shrouding the nozzle 4. The cover 22 can be constructed such that when in the closed position, the cover base 24 allows it to stand on a flat surface and the centre of gravity of the pressurised dispensing container 3 lies ahead of the rearmost point of the cover base 25, allowing the delivery device 1 to stand in a stable manner on the cover base 24.

Referring to Figure 10, an alternate embodiment of the invention disclosed in Figures 1 to 9 incorporates the flow path 19 in an alternate manner. The groove 12 is incorporated into the cylindrical wall of the chamber 8 and is closed to form a flow channel 19 by a cylindrical wall on the insert 11. In this depiction the radial flow channel 13 is shown produced in the end face of the chamber 8. It will be appreciated that there is no significance as to the location of the flow channel 19 and the radial flow path 13 with respect to the interface between the insert 11 and the chamber 8 the concept will still function as described above irrespective of the location and a number of permutations of locations wholly or partially in one component or the other may be envisaged. Referring to Figures 11 and 12, an alternate embodiment of the invention disclosed in Figures 1 to 7 which would be more suitable for nasal administration of products. The general construction of the delivery device is similar to the device that has already been described above. However, it has a simplified nozzle arrangement 4. In use, a patient or user holds the delivery device 1, usually in one hand, and applies his or her nose to the nozzle 4. The delivery device is orientated such that the primary axis of the pressurised dispensing container 3 is tending towards vertical with the metering valve 27 facing downwards. The patient locates the nozzle 4 part way to a comfortable position in the nostril 28 of the patient. The container 3 is depressed downwardly on to its stem 7 to release a dose of product from the container 3 via the metering valve 27. The dose of product is ejected by the pressure in the container 3 and the evaporation of the liquefied propellant through the valve stem 7 and the duct 9 into an effective flow channel 19 created by the groove 12 in the insert 11 and a portion of the cylindrical wall of the chamber 8. The products flows through the flow channel 19 under the influence of the vapour pressure of the liquid propellant and continued evaporative expansion into and through the radial flow path and into and through the orifice 13.

Following administration of the product the patient releases pressure on the pressurised container 3 which returns to its resting position under the influence of internal spring force in the attached metering valve 27. The above cycle can be repeated a number of times in order to administer larger amounts of product.

All of the components of the delivery device may be plastics mouldings. The invention is not restricted to the embodiments described above and various modifications may be made within the scope of the appended claims.