CROSS-REFERENCE TO RELATED APPLICATIONSThe present application is a continuation of U.S. application Ser. No. 16/630,032, filed Jan. 10, 2020, which is a National Phase Application under 35 U.S.C. § 371 of PCT/EP2018/068304, filed Jul. 5, 2018, which claims benefit of GB 1711262.4, filed Jul. 13, 2017, the disclosures of each of which are incorporated by reference herein in their entireties.
TECHNICAL FIELDThe present invention relates to a dispensing device or system for dispensing medicament, and in particular to a dispensing device or system for monitoring when a dose of medicament has been dispensed. The present invention also relates to a method of dispensing a medicament, and in particular to a method of monitoring when a dose of medicament has been dispensed.
BACKGROUND OF THE INVENTIONThere are many ways to provide a dose of medicament to a patient or other intended recipient of the medicament, particularly when it is desired to provide multiple concurrent and/or subsequent doses of the medicament, for example as part of a treatment regimen or otherwise. A popular and convenient form of medicament is a unit dose, such as a tablet, pill, capsule, etc., for oral consumption by the recipient. Commonly, multiple unit doses are provided to the recipient in a convenient form for dispensing one or more unit doses at a time, for example in a container with a removable closure, or in a sheet having sealed doses in individual compartments, each with a rupturable or frangible cover, often referred to as a blister pack.
Such devices enable the recipient to access their medication in a portable and convenient manner, when they determine a dose is required. However, particularly where medication should be taken frequently, at regular or irregular intervals, the recipient may not remember at the appropriate time that a dose is due to be taken. Even if the recipient does extract and take a dose from the device (at the appropriate time or later when they remember to do so), they may subsequently forget that they have taken a particular dose, and may then take a further dose too soon.
Such non-compliance issues with treatment regimens are a significant problem in healthcare, leading to ineffective treatment and possible complications for the patient who may under or over dose on a medication, potentially limiting the effectiveness of their long term treatment and/or leading to exacerbations, side effects, etc. Furthermore, unused medication from missed doses must be discarded appropriately and according to local restrictions and regulations, which may be costly to implement and inconvenient.
Attempts to overcome the above issues of non-adherence to dosing regimens have been made, for example by marking individual blisters on a blister pack with an indication of when the dose should be taken. However this requires each blister pack to be customised to the recipient's specific needs and dosing regimen. More recent devices and systems have been developed, which generally contain multiple unit doses in compartments from which they can be dispensed and some form of monitoring of the compartments to determine if the unit dose has been removed and (it is implied) that it has been taken by the patient. However, despite several attempts to produce a suitable device or system, the prior art solutions have generally been very expensive to manufacture and consist of several relatively complex components, many of which are used only a single time (i.e. for one dosing period until the unit doses have all been removed) and then must be discarded. If the components of the device comprise electronics as is typically the case, again there are local regulations that must be followed for disposing of such components and the cost of such devices is prohibitively high.
Therefore there remains a need for a medicament dispenser, and a method of dispensing a medicament, that enables a patient or other intended recipient of a medicament, to reliably dispense the medicament at the appropriate time and to be able to review whether, and at what time, they took a particular dose at a time after the event. Furthermore, there remains a need for such a dispenser and method of dispensing that can be provided at an acceptable associated price, and a cost attractive, reliable, reusable, patient and manufacturing friendly adherence monitoring solution has the potential to address one or more of the above mentioned patient needs.
SUMMARY OF THE INVENTIONIn accordance with the present invention, there is provided a dispensing system and method, which overcome at least one or more of the drawbacks of the prior art. From a first broad aspect, there is provided a dispensing system for dispensing unit dosage forms from a blister pack, the dispensing system comprising: a housing for receiving a blister pack, the blister pack having a plurality of cavities with at least one unit dosage form sealed in each of the cavities, the housing comprising at least one housing aperture; a sensing layer comprising: a plurality of apertures, each sensing layer aperture configured to substantially align with a corresponding one or more of the plurality of cavities of the blister pack when a blister pack is received in the housing; and a plurality of pressure sensing regions, at least one pressure sensing region at least partially surrounding each sensing layer aperture; an electronics unit; and a power source for providing voltage to the sensing layer; wherein: in use, the unit dosage forms are dispensed from the blister pack through the sensing layer apertures and through the at least one housing aperture by application of pressure upon each cavity; and the sensing layer senses the pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack.
The dispensing system is advantageous as a blister pack having doses of a medicament, or the like, sealed in its cavities can be received in the housing of the system and a patient or other recipient of the dose of medicament (or caregiver, etc.) is able to push on a cavity to break the seal of the blister and dispense the dose in the usual manner, and the dispensing system senses the pressure of the patient expelling a dose from a cavity, enabling a reliable and more accurate determination of a dose being dispensed than in the prior art. Furthermore, the modular arrangement of the dispensing system, i.e. the housing being configured for receiving a blister pack, enables the system to be reused many times with replacement blister packs that are replenished as each previous blister pack is emptied. Therefore the electronics unit, for example, is able to be used multiple times, avoiding the cost and environmental issues associated with disposing of electronics after a single or brief use. Similarly the sensing layer can be reused multiple times. Furthermore, as the sensing layer comprises apertures, this enables the blister pack to be inserted on top of the sensing layer in the housing, thus it is easy and convenient for a patient to drop their blister pack into the assembled system.
The system is particularly beneficial for unit dosage forms (pills, tablets, capsules, etc.) that are provided to the patient in standard blister packs, as is the case for many of the medicaments dispensed in many countries. Standard blister packs typically have multiple cavities spaced apart in a regular or irregular array, with a single dose of medicament in each cavity, that can be expelled from the blister pack by collapsing the cavity with pressure (from the patient's finger or thumb, for example) and pushing the dose through a rupturable seal over the cavity. The term “standard” here is intended to indicate prior art blister packs of various sizes, shapes and configurations, that may be specific to a particular medication but are generally mass-produced in a similar form for each medication. Therefore, a user of the system can simply insert a standard blister pack into the housing and dispense the doses at the required times, the system determining the dispensing events so that adherence or non-adherence to a dosing regimen is recorded for further reference. When all doses in a blister have been dispensed, the user simply removes the empty blister pack from the housing and inserts a replacement standard blister pack to continue recording their adherence or otherwise to the treatment regimen. Advantageously, the system may comprise at least one sensor for detecting removal of the empty blister pack and/or insertion of a replacement blister pack and detection thereof enables the system to adjust or update in response to this event, e.g. to reset any counters, displays, etc., and/or to display such information to the user, etc.
As discussed above, the dispensing system uses the pressure applied by the patient to expel a dose to determine when a medicament dose is being taken by the patient. This is achieved using a sensing layer having apertures through which the doses are dispensed and pressure sensing regions. The sensing layer may comprise a pressure sensitive layer that defines the pressure sensing regions and a conductive layer, the conductive layer comprising conductive regions substantially aligned with the pressure sensing regions of the sensing layer. This arrangement is advantageous because voltage can be applied to the conductive layer and when the conductive regions of the layer contact the pressure sensing regions, current flows in the pressure sensing regions enabling the pressure sensing to occur.
The sensing layer may further comprises a spacing layer between the pressure sensitive layer and the conductive layer, the spacing layer spacing the pressure sensitive layer and conductive layer apart such that they are not in electrical contact, and the spacing layer being compressible such that the pressure sensitive layer and conductive layer can be brought into electrical contact. Therefore, when the pressure sensitive layer and conductive layer are spaced apart, any voltage provided to the conductive layer will not be provided to the pressure sensitive layer. However, as the patient pushes on the blister pack cavity to expel a dose, the spacing layer compresses and the pressure sensitive layer and conductive layer are brought into electrical contact so that voltage is provided to the pressure sensing layer and the pressure applied to the blister is determined. This open circuit/switch-type arrangement is particularly advantageous for enabling the use of small power sources in the system and for improving the operational lifetime of the system as the circuit/switch will close only when pressure is applied to the sensing layer and the spacing layer is sufficiently compressed. The spacing layer may comprise foam, which is a material that is readily configurable for the desired compressibility under an appropriate amount of pressure.
The layers of the system may be configured in any suitable manner to achieve the above functions. For example, the sensing layer apertures may be substantially circular or elliptical, and the sensing layer aperture of the spacing layer may have a larger diameter than the sensing layer aperture of the pressure sensitive layer and of the sensing layer aperture of the conductive layer, such that an air gap is provided between the pressure sensitive layer and conductive layer in the vicinity of the apertures. Namely, there is a portion surrounding the apertures of each of the pressure sensitive layer and the conductive layer that is exposed even when in contact with the spacing layer, such that as the spacing layer is compressed, the exposed portions directly contact. The apertures of the pressure sensitive layer may be substantially the same size as the apertures of the conductive layer, or one of these layers may have apertures with larger diameters than those of the other of these layers.
As discussed above, it is desirable to space apart the conductive layer to which voltage may be provided by the power source, from the pressure sensitive layer unless sufficient pressure is applied in use to bring the layers into electrical contact. Thus the sensing layer may be configured such that compression of the compressible spacing layer depletes the air gap until the pressure sensitive layer and the conductive layer are brought into electrical contact. The power source may be a battery, such as a button cell or other small battery device, and or may be rechargeable, which may be via and external source (for example by inductive coupling) and/or may be a solar cell, etc.
The pressure sensitive layer may be configured in any suitable manner such that pressure thereon is registered and/or measured in a suitable form. In particular arrangements, the pressure sensitive layer may comprise a non-conductive material comprising conductive particles dispersed therein. Such materials are typical semi-conductive, allowing current to flow through the material but not to the same extent as a conductive material and are pressure sensitive in that the resistance of the material changes (typically decreases) as pressure is applied to the material, since the dispersed conductive particles are compressed more closely together. Therefore changes in the resistance of the material can be measured at one or more different positions in the material to determine where and how much pressure is being applied to the material. Particularly useful materials for the pressure sensitive layer are those that are flexible and relatively low cost, such as materials that comprise a polymer film layer, preferably a polyolefin, such as polyethylene, layer, impregnated with conductive particles, preferably carbon black particles. Examples of suitable materials include Velostat O and Linguist and Eeonyx O. Velostat® for example, is particularly useful being thin, flexible, and easy to manufacture into the desired layers (which can be cut to shape and apertures cut therethrough). However any suitable material with appropriate properties may be used.
The conductive layer may be configured in any suitable manner such that voltage can be provided to/from the layer. Particularly for low cost dispensing systems, it is desirable for the conductive layer to be simple to manufacture and mass produce. Therefore the conductive layer may comprise a printed circuit board (PCB). Such printed electronics are convenient, easy to configure, low cost and readily printed on thin and/or flexible materials which are very suitable for use in the present system. In certain arrangements for example, where it is desired to determine a particular location where pressure is applied, the conductive regions of the conductive layer may be substantially ring-shaped and encircle the apertures in the conductive layer, each conductive region being discrete from any other conductive region of the conductive layer. Thus pressure at or around a particular blister can be discerned as the resistance change (for example) of the material at a particular location can be detected. Such conductive regions could be printed around each aperture, with traces connecting each aperture to control electronics or the like. Alternatively, for ease of manufacture, the conductive regions of the conductive layer may comprise substantially all of the conductive layer. Thus a substrate for example could have an entire coating of conductive material applied (or indeed the layer may substantially comprise conductive material) and the appropriate apertures could be cut from the layer to form the conductive layer.
The housing of the dispensing system comprises at least one housing aperture. This allows pills or the like to be pushed from a blister cavity and through the aperture in the housing. The housing aperture may, for example, cover substantially all of the base of the housing, with just a frame around the outside of the aperture defining the housing base. This enables blister packs of different configurations to be used with the housing since the housing aperture is large and aligns with all the blisters. However to provide more structural rigidity to the housing, the housing may comprise a base comprising a plurality of housing apertures, the housing apertures arranged in an array such that each housing aperture substantially aligns with at least one of the plurality of cavities of a blister pack when a blister pack is received in the housing, the blister pack being a standard blister pack. The housing apertures may be configured so as to be substantially the same size (or slightly larger) than the footprint of each blister and in a corresponding pattern, so as to match the particular blister pack. Alternatively, the housing apertures may be substantially larger than the footprint of each blister and configured to correspond with several blisters of a blister pack. In some arrangements, the base portion of the housing may be removable and replaceable with a base portion having apertures of a different configuration, to enable the housing to be customised to different blister packs.
The dispensing system comprises an electronics unit and a power source. The electronics unit may comprise components such as a processor, for processing received signals indicative of pressure being applied to the sensing layer, etc. Therefore the electrical system of the dispensing system is an active system, compared with a passive system of some prior art arrangements. The electronics unit may comprise a memory for storing data corresponding to at least the time and date at which the sensing layer senses the pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack. The electronics unit may further comprise a transmitter, which may be a wireless transmitter, which may be a Bluetooth LE transmitter, for transmitting data to a remote device, the data corresponding to at least the time and date at which the sensing layer senses the pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack and/or the data corresponding to a reminder that a unit dosage form is due to be dispensed at a predetermined date and time. Other transmitters are contemplated in other embodiments of the present invention, for example those that communicate via other wireless protocols, including WiFi, 3G, 4G, 5G, etc. Thus information relating to when a blister has been pressed and a dose therefore dispensed can be transmitted to an external device such as a computer, smartphone, smartwatch, printer or the like and the patient or caregiver is able to see data relating to whether the patient has followed their dosing regimen, and whether there are particular times where the patient has not, etc.
The dispensing system may comprise other components, for example within the electronics unit, to aid the system in efficient operation. The system may comprise an accelerometer, thus the system can determine when the user is handling the dispensing system for example. The accelerometer may be configured to determine when a level of activity above a certain threshold is detected and therefore that it is likely that the user is about to dispense a dose. The system may use this determination to wake up the necessary components of the device for detecting dispensing of a dose, and/or for selecting an appropriate algorithm for determining if a dose is dispensed, etc. The accelerometer may also be configured to determine when a level of activity below a certain threshold is detected and therefore that it is likely the dispensing system has been put away by the user. The system may use this determination to shut down any components that are not required for the underlying operation of the system, such as those for detecting dispensing of a dose (i.e. the system may switch to a sleep mode to conserve power).
As discussed above, a reminder may be transmitted to a remote device, for example to the patient's smartphone or smartwatch, to remind them when it is time to take a dose of medication so as to help them follow the dosing regimen. Additionally or alternatively, a reminder may be generated at the remote device, based on the information provided from the dispensing system. The reminder could be in the form of a message displayed on the remote device, an alarm, a visual indication such as a light flashing and/or a vibrational alert. It may additionally or alternatively be useful for the patient to receive a reminder at the dispensing system itself. Therefore the dispensing system may comprise a display for displaying a reminder and/or other useful information, and/or may comprise other means for indicating when a dose is to be dispensed such as a light that is illuminated to indicate a dosage time, and/or a vibrational alert, and/or an audible alarm, etc. The dispensing system display may additionally or alternatively display other information, for example the display may display the data discussed above, such as when pills have been taken or missed, etc.
The sensing layer of the dispensing system senses the pressure applied as a dose is dispensed from a blister pack inserted into the dispensing system. Whilst the dispensing system may be configured to determine any pressure in the vicinity of a cavity as a dispensing pressure, it might be that the pressure is not sufficient to dispense a dose of medication and/or the pressure is not due to deliberate application by the patient of pressure to dispense a dose. For example, if a patient carries a dispensing mechanism in a pocket, wallet, purse, bag, etc., then inadvertent pressure may be applied to the dispensing device from contact with other objections in the bag, etc., or as the patient moves around, and so on. Therefore it is desirable to determine if pressure applied to the dispensing system is likely to be to dispense a dose, or for other reasons. The sensing layer may therefore sense the profile of the pressure applied in the vicinity of each cavity, to determine if a unit dosage form has been dispensed from the blister pack; or the pressure has a non-dispensing pressure profile. For example, a threshold may be determined for the sensed pressure, above which it is determined that it is likely a dose was dispensed. Where the pressure sensitive layer comprises a semi-conductive material, for example, a measure of a resistance below a certain threshold may indicate a sufficient amount of pressure to dispense a dose. Additionally or alternatively, the shape of the pressure and/or its location(s) may be used to determine if a dose has been dispensed. For example, if the sensing layer senses pressure in multiple locations (perhaps of generally of the same order of magnitude at each location) then the system may determine this is more likely to be due to the dispensing system being squashed against other items in a bag, or being in a pocket, etc. By analysing a pressure pattern, for example pressure magnitude, distribution of pressure (if one side of the aperture receives higher pressure than other sides), pressure profile (i.e. how fast pressure builds up and releases), etc., the dispensing system can determine if a pill is taken. The algorithm can be implemented inside the electronics unit, or mechanically for example by adjusting the thickness of the foam and the rigidity of sensor structure to only give an indication if sufficient pressure is applied.
As discussed above, a modular dispensing system is advantageous because many of the components of the system are reusable with multiple successive blister packs. Certain of the components of the dispensing system may be more durable than other of the components. For example the housing may be formed from plastic and very rarely require replacing. Other components of the system may require more frequent replacement if, for example, the power source expires. However, in some arrangements, a replaceable and/or rechargeable battery is provided. The sensing layer may be relatively durable and not need regular replacement but it may be desirable, in optional configurations, to customise the configuration of the sensing layer for different blister packs, even if they are standard blister packs since these may have variations in their configuration and differ depending on the particular medication, etc. Therefore the housing and the sensing layer may be separable components and are configured such that sensing layers with different configurations are each receivable in the housing. The patient can then extract the existing sensing layer and drop in a replacement sensing layer to modify the dispensing system as desired. The electronics unit may be substantially enclosed within the housing, the housing having a connection opening to receive a connector of the sensing layer for connection to the electronics unit. This protects the electronics unit from damage and dirt, etc., improving the lifetime of the electronics unit. However the housing may be configured such that the enclosure can be opened to access the electronics unit or other parts of the system, to replace the power source and/or any component of the electronics unit, and/or the entire electronics unit. Therefore the system is configurable, updatable and/or upgradable and more flexible than prior art arrangements and prevents unnecessary discarding of system components.
From a further broad aspect, there is provided a method of dispensing unit dosage forms from a dispensing system having a blister pack received therein, the dispensing system comprising: a housing for receiving a blister pack, the blister pack having a plurality of cavities with at least one unit dosage form sealed in each of the cavities, the housing comprising at least one housing aperture; a sensing layer comprising: a plurality of apertures, each sensing layer aperture configured to substantially align with a corresponding one or more of the plurality of cavities of the blister pack when a blister pack is received in the housing; and a plurality of pressure sensing regions, at least one pressure sensing region at least partially surrounding each sensing layer aperture; an electronics unit; and a power source for providing voltage to the sensing layer; the method comprising: sensing with the sensing layer pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack through the sensing layer apertures and through the at least one housing aperture. The dispensing system used in the method may have any one or more of the features discussed above in accordance with the first broad aspect of the present invention. For example, the sensing layer of the dispensing device may further comprise a spacing layer between the pressure sensitive layer and the conductive layer, the spacing layer spacing the pressure sensitive layer and conductive layer apart such that they are not in electrical contact, and the method further comprising bringing the pressure sensitive layer and conductive layer into electrical contact by compressing the spacing layer.
The sensing layer apertures may be substantially circular or elliptical, and the sensing layer aperture of the spacing layer may have a larger diameter than the sensing layer aperture of the pressure sensitive layer and of the sensing layer aperture of the conductive layer, such that an air gap is provided between the pressure sensitive layer and conductive layer in the vicinity of the apertures, the method further comprising compressing the compressible spacing layer to deplete the air gap to bring until the pressure sensitive layer and the conductive layer into electrical contact.
The method may further comprise providing voltage to the conductive layer from the power source. The method may further comprise storing data corresponding to at least the time and date at which the sensing layer senses the pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack in a memory of the electronics unit. The method may further comprising detecting and/or storing other useful information, such as an identification (ID) of the blister pack inserted in the housing (which ID may, for example, be detected from a chip or tag of the blister pack that has the ID stored therein), and/or information relating to a blister pack being removed and/or inserted, and/or information related to the orientation of the blister pack, etc. The method may further comprise transmitting data to a remote device, the data corresponding to at least the time and date at which the sensing layer senses the pressure applied in the vicinity of each cavity as each unit dosage form is dispensed from the blister pack and/or the data corresponding to a reminder that a unit dosage form is due to be dispensed at a predetermined date and time. The method may further comprise transmitting data wirelessly, preferably comprising Bluetooth LE transmission.
The method may further comprise displaying the data on a display of the dispensing system. The method may further comprise sensing a profile of the pressure applied in the vicinity of each cavity, to determine if: a unit dosage form has been dispensed from the blister pack; or the pressure has a non-dispensing pressure profile.
BRIEF DESCRIPTION OF THE DRAWINGSPreferred aspects and embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG.1 is a perspective view of a dispensing system with a blister pack received therein, in accordance with embodiments of the present invention;
FIG.2 is a perspective view of the dispensing system ofFIG.1, without a blister pack;
FIG.3 is a schematic side view of a portion of the dispensing system ofFIG.1;
FIG.4 is a schematic view of a portion of the layers of a sensing layer of a dispensing system in accordance with embodiments of the present invention;
FIGS.5A to5D are schematic top views illustrating embodiments of the layers of the sensing layer ofFIG.4;
FIG.6 is a schematic view of a conductive layer of a dispensing system in accordance with embodiments of the present invention;
FIG.7 is a schematic view of a communications network for dispensing systems in accordance with embodiments of the present invention;
FIGS.8A and8B illustrate examples of information transmitted from a dispensing system in accordance with embodiments of the present invention, and displayed on a device of a patient using the dispensing system;
FIG.9A is a schematic side view of a portion of the layers of a sensing layer of a dispensing system in accordance with alternative embodiments of the present invention;
FIG.9B is a schematic top view of a portion of the conductive layer ofFIG.9A with conductive regions surrounding a conductive aperture;
FIG.9C is a schematic side view of the dispensing system layers ofFIG.9A in a compressed state as a dose is dispensed;
FIG.10 is a schematic top view of an inductive sensing layer in accordance with alternative embodiments of the present invention;
FIGS.11A and11B are schematic side views of a capacitive sensing layer in accordance with alternative embodiments of the present invention, in an uncompressed and compressed state respectively;
FIG.12A is a schematic side view of an optical sensing layer in accordance with alternative embodiments of the present invention;
FIG.12B is a schematic top view of the optical measuring layer ofFIG.12A;
FIGS.13A and13B are schematic top views of conductive layers with conductive regions in accordance with alternative embodiments of the present invention; and
FIGS.14A and14B are schematic side views of a sensing layer in accordance with alternative, simplified embodiments of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSDispensing systems (and methods) in accordance with embodiments of the present invention are configured for dispensing unit doses from a blister pack, typically a standard blister pack. Blister packs are considered to be standard blister packs when, for example, a particular medicament is dispensed in blister packs that typically remain of the same configuration for a prolonged period of time, e.g. are mass produced, and/or have a standard arrangement of multiple cavities, etc. A typical standard blister pack comprises flat sheet(s) of foils (covering each other and being attached to each other). One, relatively rigid foil, most commonly called the base, comprises cavities or open “blisters”, for accommodating a tablet or capsule each, while the other foil is flat and most commonly called the lid, and seals the opening of the cavities or blisters. The most commonly used sealing process is heat sealing, at least one of the foils having thermoplastic properties, and at present the manufacture of the pack is most rationally carried out by continuously joining webs of the foils for said sealing, and cutting them to said packs. Whereby depressing the blister from the top will cause the medication to puncture through the lid foil so that the medication is freed from the pack to be taken by the patient.
Referring toFIG.1, adispensing system2 in accordance with embodiments of the present invention is illustrated, thedispensing system2 having ablister pack30 received in thehousing4 of thedispensing system2. The blister pack comprises ablister base34, having a plurality ofcavities32 formed therein and eachcavity32 contains aunit dose38 of medicament. Thecavities32 are sealed with a frangible layer36 (not shown—seeFIG.3). Thehousing4 is of a suitable size and shape to receive theblister pack30 securely between the side edges4a,4bof thehousing4 and acover6 at one end and anend edge4cat the other. A cut out8 is provided in theend edge4cto aid the patient in lifting out theblister pack30 when it is desired to replace it with anew blister pack30.
Thecover6 of thehousing4 encloses anelectronics unit10. In the illustrated arrangement, there is provided an opening in thecover6 through which a connection to aconnector12 of the electronics unit10 (not shown—seeFIG.3) can be made. However in other arrangements the electronics unit and the sensing component(s) can be manufactured on the same printed circuit board. Typically the housing is formed from plastic, or other suitable material.
Thehousing4 is illustrated inFIG.2 with theblister pack30 removed. Thehousing4 comprises a plurality ofapertures5, which in theFIG.2 embodiment are arranged in a regular array of two by sevenapertures5, though of course other arrangements are possible in other embodiments. Thus oneaperture5 corresponds with each cavity orblister32 of theblister pack30 ofFIG.1. Therefore adose38 from eachblister32 can be pushed out through anaperture5 in thehousing4 to be dispensed to the patient. Thebase7 of thehousing4 may be integrally formed with the housing4 (e.g. the entire housing may be moulded or the like as a single component) or thebase7 may be removable from the rest of thehousing4, for example it may be slidable away from thecover6 end or may be liftable away from thehousing4. This enablesalternative bases7 to be inserted into the rest of thehousing4, for example those having a different number and/or arrangement ofapertures5, thereby enabling a different type ofblister pack30 to be used with thesame housing4. Alternatively, thehousing4 may comprise only asingle aperture5, theaperture5 being of a size so as to substantially define thebase7, thus enabling all doses38 to be dispensed from eachblister32 through thesinge aperture5. Alternatively thehousing4 may comprise two ormore apertures5, which are sufficiently sized to correspond with more than oneblister32.
Referring now toFIG.3, there is shown a portion of adispensing system2 such as that illustrated inFIG.1, from a side sectional view. Only the fourblisters32 and doses38 nearest thecover6 end are shown as is the corresponding portion of thehousing4. Thehousing apertures5 can be seen to be aligned with theblisters32, thus enabling thedoses38 in theblisters32 to be expelled through theapertures5. To dispense adose38, the patient simply pushes downwards on theblister32 with a finger or thumb, for example (as indicated by arrow P showing the general direction of pressure from the patients finger or thumb), which in turn pushes thedose38 into contact with theseal36. As theseal36 is configured to be frangible or rupturable, pressure from the dose bursts the seal and thedose38 drops out, through a correspondingaperture23,25,27 (not shown—seeFIG.4) in thesensing layer20 and through the correspondingaperture5 in thehousing4. As also shown inFIG.3, theelectronics unit10 is enclosed in thehousing cover6, with an opening to enable the sensing layer to be inserted into thecover6 for connection with aconnector12 of theelectronics unit10. Thus, voltage from a power source can be provided to thesensing layer20, or at least a portion or layer thereof as discussed further below.
FIG.4 illustrates a portion of thesensing layer20 that, in use with ablister pack30 inserted in thedispensing system2 containing thesensing layer20, would be aligned with asingle blister32 of theblister pack30. Thesensing layer20 comprises multiple component layers, including a pressuresensitive layer22, aconductive layer24 and acompressible foam layer26 separating the pressuresensitive layer22 from theconductive layer24. The pressuresensitive layer22 is shown inFIG.5A and is formed from a material that has at least one property that changes as pressure is exerted in thelayer22. For example, thelayer22 may comprises a semi-conductive layer comprising a polymer with conducting particles dispersed therein, which changes resistance as pressure is applied (typically the resistance decreases with applied pressure). Preferred materials for use for thesensing layer24 include Velostat® and the like. Other sensing methods may be used, which are illustrated inFIGS.10 to12 for example, and include capacitive, inductive, piezo electric and optical sensing and are discussed further below. The pressuresensitive layer22 comprises a plurality ofapertures23 for allowing adose38 to pass therethrough. Theapertures23 each have a diameter D23 that is larger than the largest dimension of adose38 in theblister pack30. The pressuresensitive layer22 is dimensioned to fit in thehousing4 and be retained therein, having an appropriate length L and width W.
Two differentconductive layers24,24′ are shown inFIGS.5C and5D respectively. Other configurations are also contemplated and discussed below with regard toFIGS.9A to9C andFIGS.13 and14, for example. The firstconductive layer24 ofFIG.5C comprises asubstrate29, for example of glass-reinforced epoxy laminate, glass fibre, or other suitable substrate material, withconductive regions25bprinted or otherwise provided thereon. Theconductive regions25bare generally ring-shaped or tablet-shaped (e.g. adapted to be substantially the same shape and slightly larger than the tablet of the particular blister pack) and surround theapertures25 of theconductive layer24. Theconductive regions25bare formed of any suitable material such as copper, for example. Theconductive layer24 may comprise a printed circuit board (PCB) as shown inFIG.6, havingapertures25asurrounded byconductive regions25band traces11 connecting the conductive layers to theelectronics unit10, etc., all printed onto asubstrate29 or etched to expose the conductive regions and traces. This arrangement provides discreteconductive regions25bwhich can transmit voltage to the pressuresensitive layer22 when in contact with that layer in the vicinity of thesensing layer apertures23,25,27. The diameter D25bof theconductive regions25bis larger than the diameter D25aof theapertures25a.
The alternativeconductive layer24′ ofFIG.5D is formed from conductive material, for example from a copper sheet or other suitable material, or may be formed from a substrate with a layer of conductive material printed thereon (not shown). The diameter D25of theapertures25 is generally the same as those of theFIG.5C embodiment.
Aspacing layer26 is provided between the pressuresensitive layer22 and theconductive layer24,24′. Thisspacing layer26 is compressible, being made of compressible foam for example, and whilst it spaces the pressuresensitive layer22 apart from theconductive layer24,24′ when no pressure is applied, pressure from a user dispensing adose38 from ablister32 compresses thespacing layer26 and brings the pressuresensitive layer22 and theconductive layer24,24′ into electrical contact. Theapertures27 of thespacing layer26 are configured to enable the pressuresensitive layer22 and theconductive layer24,24′ to make contact, since theapertures27 of thespacing layer26 have a diameter D27larger than the diameters D23, D25, D25aof theapertures23,25,25aof the pressuresensitive layer22 and of theconductive layer24,24′. Namely anair gap21 is formed adjacent the edges of thespacing layer26 surrounding theaperture27 which exposes the surface of the pressuresensitive layer22 in the region of theaperture23 of that layer to the surface of theconductive layer24,24′ in the region of theaperture25 of the conductive layer (i.e. exposes theconductive region25bof the embodiment ofFIG.5C). Thus, as the pressuresensitive layer22 and theconductive layer24,24′ are compressed towards each other, the exposed regions can be brought into direct electrical contact. Therefore current from theconductive layer24,24′ can flow through the pressuresensitive layer22 and into aconductive contact layer16 and back through the pressuresensitive layer22 and further back into theconductive layer22,24′ as the circuit is closed by the layers contacting each other under deformation. This will be discussed in further detail below in relation toFIG.9.
As shown inFIG.4, on top of the above threelayers22,24,26 additional layers are provided in this embodiment, including aprotective plastic layer14, formed of polyethylene terephthalate (PET) for example, and the additionalconductive layer16, hereinafter referred to as acontact layer16 for ease of reference. Thecontact layer16 is arranged above the pressuresensitive layer22 and is formed of a conductive material, such as carbon (e.g. graphite) or aluminium, etc., preferably being flexible and thin. Abroken portion17 of theprotective layer14 may extend into theapertures23,25,27 of the threemain sensing layer20 layers in use, or (as shown inFIG.9) theprotective layer14 may simply flex and not break, providing further protection to the system (if theprotective layer17 is above the dosage being dispensed). Thebroken portion17 of theprotective layer14 in theFIG.4 arrangement covers thecontact layer16 and protects thecontact layer16 and the edges of theapertures23,25 of the pressuresensitive layer22 and theconductive layer24,24′ (and thus the airgap21) from dirt and other contaminants. Similarly the unbroken portion of theprotective layer14 ofFIGS.9A and9C protects thecontact layer16, etc.
FIGS.9A to9C illustrate a portion of a sensing layer in accordance with alternative embodiments of the present invention. This arrangement again includes aconductive layer24 and thelayer24 is arranged on asubstrate29, the substrate comprising glass fibre. Theconductive layer24 is printed on thesubstrate29 as is known in a standard PCB arrangement (which is shown inFIG.9B). Theconductive layer24 comprises at least oneaperture25a,withconductive regions25barranged around the aperture, though in this embodiment, theconductive regions25bare isolated from each other and do not form a solid ring around theaperture25a,but are generally arranged in a ring shape. Thesubstrate29 also includes appropriate apertures (not shown in the Figures). Thesensing layer20 ofFIG.9A further comprises other layers in a similar manner to earlier embodiments, including afoam layer26, a pressuresensitive layer22, comprising Velostat or other suitable material, acontact layer16, of carbon or the like, aprotective layer14, of PET or the like, etc.
As illustrated inFIG.9C, when it is desired to dispense a unit dose such as a tablet, downward pressure P is applied to a dose inside a blister (not shown) and this pressure P compresses the layers of thesensing layer20, particularly thefoam layer26. The layers are thus brought together andconductive layer24 contact the pressuresensitive layer22, which in turn contacts thecontact layer16. As illustrated by the line a′-b′, voltage applied to theconductive layer24 can therefore pass through theconductive layer24 to the pressuresensitive layer22 and into thecontact layer16, then back through the pressuresensitive layer22 into theconductive layer24. ComparingFIG.9C withFIG.9A, the circuit is closed inFIG.9C due to the pressure P and voltage passes through the pressuresensitive layer22, thereby enabling a determination of pressure being applied and where it is applied (particularly due to the isolatedconductive regions25bshown inFIG.9B), whereas inFIG.9A, absent any pressure, the circuit is open and no voltage passes to the pressuresensitive layer22.
Referring now toFIG.7, dispensingsystems2 in accordance with embodiments of the present invention are illustrated in use in anexemplary network40. Each dispensingsystem2 comprises a transmitter, such as a Bluetooth LE transmitter, within theelectronics unit10 or otherwise connected thereto. Theelectronics unit10 also comprises a memory in which information (relating to eachdose38 dispensed from an insertedblister pack30 and determined as dispensed by the sensing layer20) is stored, the information including at least the time and date when themedicament dose38 was dispensed. The transmitter of thedispensing system2 transmits the data to a remote device, such as asmartphone device42 of the patient, either continuously or at regular or irregular intervals, or when thesmartphone42 is detected as being in range of thedispensing device2, or when power is supplied to the transmitter of theelectronics unit10, etc. In alternative arrangements, the data may be transmitted additionally or alternatively to other remote systems, such as to a computer of the patient and/or of a caregiver responsible for treatment of the patient, etc.
Thesmartphone42 is provided with suitable software, such as anappropriate application50, so that the information contained in the data is displayed on thesmartphone42, as shown inFIG.8A. Therefore the patient (or caregiver or other recipient of the data) can easily view historical data relating to eachdose38 dispensed from ablister pack30 using thedispensing device2. For example, the patient can see whether they have adhered to the treatment regimen, for example as indicated with atraffic light arrangement52 as shown inFIG.8A (where colours may be used on the display device but are not shown in the Figures). The “green”indicators54 illustrate that adose38 has been dispensed at the appropriate time with “red”indicators56 showing that adose38 was not dispensed when it should have been. The “white”indicators55 show doses38 that have yet to be dispensed but are not yet due to be taken. The position of thedose38 in theblister pack30 may be indicated with adisplay52 having the same number and arrangement ofblisters32 as theblister pack30, for example. Theapplication50 may additionally or alternatively showother information58 to the patient, such as the exact time and date of dispensing eachdose38 and whichdose38 in the treatment regimen was taken (i.e. the first, second, third, etc., dose), with thezeroth dose59 indicating when anew blister pack30 is inserted into thedispensing device2 and thus begins a new treatment regimen.
Additionally or alternatively, as shown inFIG.7, information regarding dispenseddoses38 can be sent from thedispensing system2 directly or indirectly (e.g. via asmartphone42 as illustrated in the Figure) to another device of the patient, such as asmartwatch44. For example, anindicator45 may be triggered on the patient'ssmartwatch44 immediately on dispensing adose38, to inform the patient that thedose38 they have taken has been successfully registered as shown inFIG.8B. Other information, including the same information as may be displayed on theapplication50 of thesmartphone42 can also or alternatively be displayed on thesmartwatch44.
As also shown inFIG.7, data from thedispensing system2 may additionally or alternatively be transmitted to another remote location, such as aserver46, etc. This facilitates long term storage of the data and allows, for example, a caregiver such as a physician to access the data if the data is available from theserver46 via the Internet without the patient needing to attend the physician's office or the like.
The above embodiments comprise pressure sensing arrangements but alternative embodiments having alternative sensing layers are also contemplated within the scope of the present invention. For example, as illustrated inFIG.10, an induction sensitive layer122 (or inductive layer122) is disclosed, which may be used in any suitable embodiment described above or below instead of a pressuresensitive layer22. Theinductive layer122 comprises an induction coil layer126 (or any other suitable means in which an electromotive force may be induced) and aninduction coil substrate124. When theinduction coil layer126 andinduction coil substrate124 are deformed (for example due to pressure P applied to the layers as per the embodiment illustrated inFIGS.9A to9C), a change of the electrical properties of the inductor can be detected. Therefore pressure, indicative of a dose being dispensed, is determined in the region of the coils, which surround anaperture125 in thelayer122 through which the dose is dispensed. Alternatively, theinduction coil layer126 couples to an inductive layer in blister (34 inFIG.3), which coupling is changed if the inductive layer in blister moves or is ruptured due to tablet removal. This change in coupling is then detected by theinduction coil126.
FIGS.11A and11B illustrate another alternative embodiment in accordance with the present invention, which comprises a capacitance sensitive layer222 (or capacitive layer222). Much like theinductive layer122 embodiment described in relation toFIG.10, thiscapacitive layer222 operates on the same principle of layers being brought closer together and thus, in this case, the capacitance of the layers alters and thereby indicates pressure applied to the layers in bringing them together. In more detail,capacitive layer222 comprises asubstrate229 with afirst capacitor layer224 above thesubstrate229. Afoam layer226 is provided between thefirst capacitor layer224 and asecond capacitor layer216, these twocapacitor layers224,216 forming a capacitor having a capacitance Cu. Also provided are other suitable layers such as aprotective layer214 as in other embodiments. As pressure P is applied to the capacitive layer222 (as a dose is pushed from a blister—not shown), the capacitor layers224,216 are brought into closer proximity, changing the capacitance Cu(from the uncompressed state) to a different capacitance Cu, in the compressed state (e.g. increasing the capacitance). Thus the change in capacitance is indicative of a dose being dispensed from a blister pack associated with thecapacitive layer222.
FIGS.12A and12B illustrate another alternative embodiment in accordance with the present invention, which comprises an optical sensitive layer322 (or optical layer322). In the illustrated embodiment, ablister pack30 is shown above theoptical layer322 having ablister32 containing a unit dose ofmedicament38. Beneath theblister pack30 theoptical layer322 comprises asubstrate329 with at least oneoptical transmitter304 aligned across an aperture321ain thesubstrate329 with at least oneoptical receiver306. Theoptical transmitter304 is configured to emit, either continuously or intermittently (for example only when powered and/or at regular intervals), alight beam302 in the direction of a corresponding optical receiver and across a corresponding aperture321a.If adose38 is dispensed from theblister pack30 and passes through the aperture321a,thelight beam302 is temporarily interrupted by the passage of thedose38 and thus dispensing of adose38 is detected.FIG.12B illustrates a top view of theoptical layer322, illustrating that a plurality ofcorresponding transmitters304 andreceivers304 may be used to detect dispensing through each aperture321ain thesubstrate329. Of course, other configurations of this layer are within the scope of the invention. Furthermore, other layers from earlier embodiments, for example aprotective layer314, may also be provided in this optical embodiment.
The above embodiments are illustrative of arrangements in accordance with the present invention, but are non-limiting and the scope of the invention is defined by the claims. It will be appreciated that other arrangements of each of the above examples are possible. For example, other resistive embodiments are illustrated inFIGS.13A to13B and14A to14B.FIGS.13A and13B illustrate two, alternative arrangements of the conductive regions of a conductive layer. InFIG.13A, theconductive regions426 do not surround each of theapertures425 in theconductive layer424, but instead are located at the corners of theconductive layer424. This simplified structure will still detect pressure applied to a pressure sensitive (or other) layer associated therewith (not shown) and is simpler to manufacture. Another arrangement is illustrated inFIG.13B, which has multipleconductive regions426′ arranged in an array aroundprolonged apertures425′, through which doses from multiple cavities of the blister pack can be dispensed. This provides a more accurate, compared to the arrangement ofFIG.13A, determination of from where a dose is dispensed, but at the same time providing a more generic configuration able to accommodate broader blister cavity arrangements, thus allowing for possible reduction of manufacturing costs due to reduced number of adaptations needed for each particular product blister.
It will also be appreciated that although in some embodiments above multiple layers form the sensing layer and/or are associated therewith, not all embodiments require all these layers and/or additional layers may be provided as required.FIG.14A illustrates asimplified sensing layer520, which is similar to thesensing layer20 ofFIG.9A, and comprises aprotective layer514, afoam layer526, aconductive layer524 and asubstrate529, but comprises a combined pressure sensitive andcontact layer522.FIG.14B illustrates a further simplifiedsensing layer620, which is similar to thesensing layer20 ofFIG.14A, and comprises aprotective layer614 and asubstrate629, but comprises a combined pressure sensitive, foam, conductive andcontact layer626. It will be understood therefore that many modifications can be made to embodiments of the present invention without departing from the scope of the invention, as defined by the appended claims.
A method of using thedispensing system2 of some of the various embodiments is now described. A patient is provided with thedispensing device2, either with afull blister pack30 already inserted into thehousing4, or separately from theblister pack30, which may be dispensed to the patient in a separate transaction from the pharmacy for example. In this latter case, the patient simply inserts theblister pack30 into thehousing4, for example dropping or sliding theblister pack30 into place between theedges4a,4bof thehousing4 and the ends defined by thecover6 and theopposite end4c.Theblister pack30 is a close fit inside thehousing4, thus ensuring good alignment of theblisters32 with theapertures23,25,27 in thesensing layer20.
In this rest configuration, voltage from the power source is provided to theconductive layer24, but the pressuresensitive layer22 is isolated from theconductive layer24 by theair gap21 defined by the larger apertures of thefoam layer26. Therefore thedispensing system2 is in a lower power mode, saving the e.g. battery power until it is desired to dispense adose38.
The patient may receive a reminder from thedispensing system2 to prompt the patient to take adose38 at the appropriate time, or may otherwise determine adose38 should be dispensed. To do so, the patient simply pushes downwardly on aparticular blister32, as generally indicated by arrow P inFIG.3. Pressure on thecavity32 from the patient's finger or thumb or the like, pushes thedose38 into contact with theseal36 of theblister base34 and through theseal36 which is configured to rupture under such pressure. Thedose38 thus drops out of thedispensing system2 through theholes23,25,27 in thesensing layer20 and thehousing apertures5 and the patient can take thedose38.
As the patient pushes downwardly on theblister32, not only is adose38 pushed through theseal36 and out of thedispensing system2, but also thefoam layer26 of thesensing layer20 is compressed. This brings the pressuresensitive layer22 and theconductive layer24,24′ closer together and if thefoam layer26 is configured to be sufficiently compressible, the pressuresensitive layer22 and theconductive layer24,24′ can be pressed into direct electrical contact, by virtue of the portions of eachlayer22,24,24′ being exposed to each other due to thelarger apertures27 of thefoam layer26. Voltage is therefore provided to the pressuresensitive layer22 by this direct electrical contact with theconductive layer24,24′. Thus, only when it is necessary to dispense adose38 is voltage provided in a timely manner to the pressuresensitive layer22 and this layer is used to sense the pressure applied to theblister32, for example by measuring the change in resistance of the pressuresensitive layer22 as it is compressed. Theelectronics unit10 stores this information regarding the change in resistance of the pressuresensitive layer22 and either transmits the information for further processing to aremote device42,44,46 and/or processes the information to determine the time/date of thedose38 being dispensed. In other illustrated embodiments, the sensing layer senses a different change or variation in state to determine that a dose has been dispensed, for example a change in capacitance (as shown inFIG.11), or an interruption of a light beam (as shown inFIG.12), or an induced voltage (as shown inFIG.10), etc.
In some embodiments, thesensing layer20 is a removable component from thehousing4. If adifferent blister pack30 is to be used with thedispensing system2, adifferent sensing layer20 having a configuration that corresponds with the configuration of thedifferent blister pack30 can be inserted into thehousing4 in replacement for the existingsensing layer20. If thehousing4 comprisesapertures5 in an array generally corresponding to theblisters32 of theblister pack30, then thebase7 of thehousing4 may be configured to be removable from the remainder of thehousing4 and areplacement base7 can be provided with a configuration corresponding to that of thedifferent blister pack30.
As disclosed in the various embodiments above, amodular dispensing system2 is provided, in which standard blister packs30 are received and in the event that adose38 is dispensed from ablister32 of theblister pack30, this is detected by thedispensing system2 and the dispensing of adose38 is displayed or recorded for future reference. Thus animproved dispensing system2 is provided, that is cost attractive, reliable, reusable, patient and manufacturing friendly, and that aids a patient in adhering to a dosing regimen and provides relevant information for review by the patient and/or a care giver as adose38 is dispensed and/or at an appropriate time afterseveral doses38 have been dispensed.