US 4,946, 069 discloses a single use dispenser for discharging small quantities of liquid. This dispenser comprises a body which has a pump cylinder including a liquid reservoir containing a dose of a liquid to be dispensed and a piston arranged within the pump cylinder. The piston has an outlet channel along its length to connect the liquid reservoir with an outlet nozzle. In use the pump cylinder is displaced with respect to the piston so that liquid from the reservoir is discharged from the reservoir, through the outlet channel and out of the outlet nozzle. A disadvantage of this type of device is that since the outlet channel communicates with the outside environment, the liquid in the reservoir is not entirely closed off from the outside. There is therefore a possibility of permeation into or out of the device.

EP 0 546 607 discloses another single use dispenser. In this dispenser a container of the substance to be discharged is mounted on a piston member and a seal is arranged across the container to seal in the substance to be discharged. The dispenser has a hollow stainless steel needle which extends towards the seal such that in use the needle is arranged to penetrate through the seal and the substance to be discharged is then expelled from the container and through the hollow stainless steel needle to an outlet. A disadvantage of this type of device is that it can generate particulates when piercing. There is also the possibility of contamination of the substance to be discharged from the needle, both from the difficulty of cleaning the narrow channel within the needle and the possible presence of oils etc on the needle surface from the production of the stainless steel. Moreover, the precompression system used by this device which includes a snap ring produces a variation in the actuation force, mainly due to the manufacturing process, materials properties and tolerance stack up such that it may be difficult to force the needle through the seal resulting in awkward activation of the dispenser. Furthermore, once used there are possible safety implications from the disposal of dispensers containing sharp needles.

It is an object of the present invention to overcome the disadvantages discussed above.

According to a first aspect of the present invention there is provided a hand held pharmaceutical dispenser comprising first and second portions movable relative to each other; the first portion having or being arranged to receive a container to contain a pharmaceutical product to be dispensed and having an annular collar provided in the container with a resilient means provided between the annular collar and the second portion; and the second portion having a stopper to releasably engage the annular collar to seal a pharmaceutical product within the container; the first and second portions being arranged such that when they are at first relative positions the stopper is arranged to engage the annular collar to seal a pharmaceutical product in the container and when the first and second portions are pushed towards each other the annular collar is driven down into the container, with a periphery of the annular collar still maintaining a seal with the inside surface of the container until the pressure within the container overcomes the force generated by the resilient member acting on the annular collar so that the stopper is disengaged from the annular collar such that, in use, pharmaceutical product may be dispensed from the dispenser.

The releasably engageable stopper provides a means of sealing a pharmaceutical product when the first and second portions are at first relative positions and of enabling a pharmaceutical product to be discharged when the first and second portions are moved to second relative positions, overcoming the disadvantages associated with a needle discussed above whilst still sealing the pharmaceutical product from the permeation into or out of the device.

The stopper, or at least a portion of its outside surface, is preferably made from an elastomer, a plastic or a combination of the two such as a thermoplastic elastomer.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which Figure 1 is an exploded view of a dispenser according to the present invention ; Figure 2 is a cross-sectional view of the assembled dispenser before actuation;

Figure 3 is a cross-sectional view of the dispenser being actuated and Figure 4 is a cross-sectional view of the dispenser after actuation.

Figure 1 shows the components of a dispenser illustrating the present invention. An actuator 10 has an outlet 11 through which a pharmaceutical product may be dispensed. The outlet 11 is provided at the end portion of a generally frusto- conical shaped nozzle portion 12, which in this example has a shape and size to enable it to be easily inserted into a user's nostril. A body portion 13 connects the nozzle portion 12 to a skirt 14 which is shaped and sized to engage and be movable relative to a base portion 70. The skirt 14 has two external shoulders 15 with a shape and size to enable a user's fingers to engage them. The underside of the skirt 14 is provided with a set of recesses (not shown in this figure) arranged to engage corresponding protrusions 72 in the base portion 70 to maintain the actuator 10 and the base portion 70 in predetermined relative positions before use.

A member 20 is provided having a first end portion 21 and a second end portion 22. The first end portion 21 is arranged to be received and fixed in the actuator 10 and has a channel 23 formed along its length through which pharmaceutical product may pass to the outlet 11 of the actuator 10. The second end portion 22 is arranged to receive a sleeve 30 which in use slides over the second end portion 22 of the member 20. The second end portion 22 and the sleeve 30 are arranged such that a gap is provided between the outer surface of the second end portion 22 of the member 20 and the inner surface of the sleeve 30 through which pharmaceutical product may pass to the channel 23 and the outlet 11. A first end 31 of the sleeve 30 is arranged to engage the actuator 10. A second end 32 of the sleeve 30 supports a stopper 33. The stopper 33 provides a seal when in contact with an annular collar 40 which in use is assembled over the sleeve 30. The annular collar 40 seals with the stopper 33 when the actuator 10 and base 60 are in first relative positions.

The stopper 33, or at least a portion of its outside surface which engages the annular collar 40, is made from a material which has low leachable and extractable characteristics and good resistance to gas and liquid permeability. The stopper 33 could undergo a barrier process to provide these qualities to the surface of the stopper 33. To provide these properties the stopper 33 or at least a portion of its outside surface, could be made from an elastomer, a plastic or a combination of the two such

as a thermoplastic elastomer. Examples of suitable thermoplastic elastomers include Santoprene, Pebax, Vitaprene, Hytrel or the like. The annular collar 40, or at least a portion of its outside surface which engages the stopper 33, is made from a material with similar properties to the stopper 33 and is preferably made from the same material as the stopper 33.

A resilient member, in this embodiment a spring 50, is provided on the outside surface of the sleeve 30. When the dispenser is assembled, one end of the spring 50 engages the actuator 10 and the other end of the spring 50 engages the annular collar 40 as shown in figures 2,3 and 4.

The annular collar 40 is arranged to be provided inside a container 60. The outside surface of the annular collar 40 is sized to engage and seal against the inside surface of the container 60. The container 60 may be made from any suitable material such as stainless steel, plastic or glass and contains a single dose of pharmaceutical product.

The base portion 70 has a suitably sized periphery to be received within the skirt 14 of the actuator 10 and has a support 71 to support the container 60. If desired, the container 60 and base portion 70 could be provided as a single part to reduce the number of components. Protrusions 72 are provided to be received in a set of corresponding recesses on the inside of the skirt 14 of the actuator 10 to maintain the base portion 70 and actuator 10 in predetermined relative positions before use. The underside 73 of the base portion 70 is concave so that during use a user may conveniently grip the dispenser by placing a finger on each of the shoulders 15 and a thumb on the concave underside 73 of the base portion 70 and dispense pharmaceutical product from the outlet 11 by squeezing the actuator 10 and base portion 70 towards each other.

Figure 2 shows a cross-sectional view of the assembled dispenser prior to actuation. The actuator 10 and base 70 are maintained in their pre-actuated relative positions by the protrusions 72 of the base being engaged within a set of recesses on the underside of the skirt 14 (not shown). If desired a tamper evident seal may be provided on the outside of the dispenser to indicate to a user that the dispenser has not been accidentally actuated prior to use. When the dispenser is actuated by the base 70

and actuator 10 being moved towards each other, the protrusions 72 of the base are forced or'snapped'out of the set of recesses.

Prior to use, the container 60 is provided with a single dose of pharmaceutical product, usually in liquid form. The first end portion 21 of the member 20 is inserted into the inside of the nozzle portion 12 of the actuator 10 and the sleeve 30 with the spring 50 and annular collar 40 on its outside surface is fitted over the second end portion 22 of the member 20. One end 51 of the spring 50 engages an annular surface 16 on the inside of the actuator 10 and the other end 52 of the spring 50 engages the annular collar 40. The annular collar 40 is inserted into the vial 60 to form a seal between its outside surface and the inside surface of the container 60. Prior to actuation as shown in Figure 2, the stopper 33 is engaged with a sealing surface 41 on a lower side of the neck of the annular collar 40 to seal the pharmaceutical product within the container 60.

Manually depressing the base portion 70 and actuator 10 of the nasal single dose dispenser together causes the member 20 and stopper 33 to move towards the bottom of the container 60. This movement causes the annular collar 40 to be driven down into the container 60, with a periphery of the annular collar 40 still maintaining a seal with the inside surface of the container 60. When the pressure within the container overcomes the force generated by the spring 50 acting on the annular collar 40, the stopper 33 unseats relative to the annular collar 40 and when openings 34 between the sleeve 30 and the stopper 33 are exposed as shown in Figure 3, liquid is forced up through a fluid flow path through openings 34, between the sleeve 30 and member 20 and out through outlet 11. The spring force therefore provides a pre- compression mechanism to generate the pressure required to break up particles of pharmaceutical liquid in the container plus also provides a very smooth and repeatable operation. The action of forcing or'snapping'the profusions 72 out of the first set of pre-actuation recesses on the skirt of the actuator 10 also generates pressure to break up particles of pharmaceutical liquid in the container and provides a very smooth and repeatable operation.

As liquid is forced out of the container 60, the force generated by the spring 50 pushes the annular collar 40 into the base of the container as shown in Figure 4.

Many variations may be made to the example described above whilst still falling within the scope of the invention. For example the stopper 33 and annular collar 40 may be made from any suitable materials able to seal a pharmaceutical product in the container 60. Any number of the components which are shown in the above example as being separate may if desired be incorporated into a single component, such as for example the spring 50 and annular collar 40 or the actuator 10 and spring 50.

The pharmaceutical product could be any suitable fluid including, for example, a pure drug or a drug with a liquid and/or a pharmaceutical acceptable excipient.

The example described above is for a single dose liquid device. However the device could also be used as a bi-dose device, for example by including a twist action that would have a two position actuation, or a clip/button that can be used as a stop for the first actuation then removed or pushed to allow for the second actuation. Another variant could be to have a two stage button and base actuation in which the button is depressed for the first actuation, then the base is depressed for the second actuation.

If desired, the actuator 10 could be provided with a second set of recesses with which the protrusions 72 could be engaged after actuation to maintain the actuator 10 and the base portion 70 in predetermined post-actuation relative positions preventing further use.

Either or both of the actuator 10 and base portion 70 could be provided with protrusions 72, with the other or both of the actuator 10 and base portion 70 being provided with corresponding recesses to be engaged with the protrusions 72 before, and if desired after, actuation.

An indication could be provided on the side of the base portion 70 or actuator 10 which is visible before actuation but which becomes hidden from view after actuation. This indication could indicate to a user that the dispenser has not yet been actuated.