WO2014184781A1

WO2014184781A1 - Counting device for dispensing pharmaceutical substances

Info

Publication number: WO2014184781A1
Application number: PCT/IB2014/061493
Authority: WO
Inventors: David Slovick; Andrew Seddon; Richard Bebbington; Mark HELMICH; Gary Ross
Original assignee: David Slovick
Priority date: 2013-05-17
Filing date: 2014-05-16
Publication date: 2014-11-20
Also published as: GB201308935D0

Abstract

A counting device is disclosed for collecting a predetermined number of microspheres of a drug from a canister. The device has a head to be placed in use above the microspheres canister. The head comprises a plurality of flow channels each selectively connectable to a low pressure source by means of a valve and being connected to a predetermined number of ports, each port being operative to collect a single microsphere of the drug from the canister when the associated channel is connected to the low pressure source. Figure 3

Description

COUNTING DEVICE

FOR DISPENSING PHARMACEUTICAL SUBSTANCES

Field of the invention

The present invention relates to dispensing

pharmaceutical formulations.

Background of the invention

Medicinal dosage forms (such as tablets or capsules) contain an active substance present in micro- or milli-gram amounts combined with inactive substances which promote physical or chemical stability, ease of handling and

identification of the product.

Current European guidance prefers that tablets be sold in 'original dispensing packs' consisting of a metal foil laminated onto a plastic 'blister' sheet, containing a one month supply of individual tablets, affording a useful shelf life.

Patients with serious conditions such as ischaemic heart disease or congestive heart failure are required to take daily a large number of medications, which frequently results in a failure to comply accurately with the

recommended prescription. This can be due to:

* forgetting pills

* confusion with dosing schedules

* unwillingness or fear of consuming large numbers of pills

* errors in taking medications resulting in running out of some pills before others. A formal study has shown patients 'encash'

prescriptions given by medical practitioners at local pharmacies for approximately 60% of the calculated total necessary number of pills, when given a regular prescription of one single tablet daily. When the prescription is for two pills daily, the encashment rate can fall to only 15%.

Taking a sub-optimal number of pills would adversely affect quality of life and also reduce survival prognosis, since many treatments are life-extending, particularly when used in combination.

To mitigate this problem, it has previously been suggested that blister packing be offered as a free service by dispensing pharmacists, putting a number of tablets together in a day-coded package. However, patients are still faced with the same large number of tablets to take, which discourages them from taking their treatment reliably.

Blister packing is currently performed by only a few

dispensing pharmacists, as a special service.

It has further been proposed to manufacture tablets containing fixed dose combinations of two or more active substances. This proposal suffers from the disadvantage that fixed dose combination tablets (typically of two active substances) are recommended only for patients who have previously been stabilised on the individual components. Any particular fixed dose combination made by a manufacturer might be unsuitable or harmful for some patients, by causing metabolic disturbances or excessive or inadequate effects.

With a view to mitigating the above problem, it has previously there has been proposed by the present Applicant in EP 1476118, which is believed to represent the closest prior art to the present invention, a device for filling a set of capsules with microspheres containing active

substances to permit the dosage of each individual active substance in each capsule of the set to be varied to suit the requirements of an individual patient, which device comprises a plurality of loading stations each receiving a canister filled with micro-spheres containing a predetermined quantity of a respective one of the active substances, a programmable metering unit associated with the loading stations for metering programmed numbers of

microspheres from the individual canisters, and means for introducing the counted micro-spheres into the individual capsules of the set.

In order to meter the correct number of microspheres from a supply canister into an individual capsule, it is possible to use as a programmable counter a reciprocating perforated plate, or an indented wheel, controlled by an indexing stepping mechanism. As an alternative, individual microspheres may be counted optically (by interruption of a light beam) and the flow of microspheres into a capsule may be stopped when the desired number has been reached.

However, such a method of counting can be slow and may not prove entirely reliable.

Object of the invention

The present invention seeks to a provide a counting apparatus that allows a desired number of microspheres to be counted quickly and reliably. Summary of the invention

According to the present invention, there is provided a counting device for collecting a predetermined number of microspheres of a drug from a canister, the device having a head to be placed in use above the microspheres canister, the head comprising a plurality of flow channels each selectively connectable to a low pressure source by means of a valve and being connected to a predetermined number of ports, each port being operative to collect a single

microsphere of the drug from the canister when the

associated channel is connected to the low pressure source. In some embodiments, the counting device is a binary counting device, the head having a number of channels each connected to a different number of ports, and the numbers of ports connected to the different channels being different powers of two. The head may in some embodiments have nine channels so as to be capable of collecting a total number of microspheres from 0 to 511.

Each port may comprise a hemispherical cavity having the same radius of curvature as the microspheres, each cavity being in fluid communication with an associated channel .

If desired, the channels may be selectively connectable to a high pressure source to blow collected microspheres clear of the ports.

In some embodiments, a pressurised source of air controlled independently of the low pressure source may be provided for discharging gas under pressure through the head into the drug canister to dislodge from the head any

microspheres that are not retained within a port by suction.

According to a second aspect, the invention provides a method of dispensing a predetermined number of microspheres from a canister using a counting device as set forth above, which method comprises determining the number of

microspheres of a drug required, positioning the counting head above the canister in proximity to the microspheres, operating the valves connecting the channels of the head to the low pressure source to such a microsphere into each port in fluid communication with the low pressure source,

positioning the counting head above a dispensing position; and disconnecting the ports from the low pressure source.

The step of disconnecting from the low pressure source may additional include connecting the ports to a source of high pressure gas in order to expel any collected

microspheres .

In some embodiments, the method may further comprise the step of blowing a gas over the ports to expel any microspheres not held by suction in a port, prior to moving the counting head to the dispensing position.

In accordance with a further aspect of the invention, there is provided a method of filling a pharmaceutical capsule with at least one type of microspheres of an active substance comprising the steps of determining the desired dosage of active ingredient required by a patient,

determining the amount of active ingredient in one

microsphere, calculating the number of microspheres required in each capsule to achieve the desired dosage, counting and collecting the correct number of microspheres from a

canister by the use of a counting device as set forth above, dispensing the collected microspheres into an open capsule, and sealing the capsule.

Brief Description of Drawings

The invention will now be described further with reference to the accompanying drawing in which:

Figure 1 is a plan view of a complete counting head,

Figure 2 shows a cut away view of the positive pressure ports and outlets of the counting head of figure 1,

Figure 3 shows a cutaway view of the negative pressure ports and ports of the counting head of figure 1, and

Figure 4 shows a capsule filling apparatus.

Detailed Description of Drawings In Figure 1, there is shown a head 10 of a counting apparatus having a predominantly hollow body for allowing the passage of fluid, in this case air and/or pressurised gas. The head 10 has a collection surface 12 which is intended to pick up or collect microspheres of a given drug from a canister. This is achieved by the aid of ports 14 formed in the collection surface 12. Each port 14 is

hemispherical in shape and accurately sized to receive a microsphere, preferably of uniform and standard size.

In the illustrated embodiment, the ports 14 are formed into groups, all the ports of a group being connected to a common channel 16, these groups and channels being

represented by dotted lines in Figure 3. Each of the

channels is connected by way of a respective independently controlled valve to a low pressure source, that is to say a suction source or a source or air at below the ambient atmospheric pressure. Depending on the state of the valve, connection of a low pressure or pressure source to the hollow body will then either raise or reduce the pressure at the ports in order to collect or eject a microsphere. The unique number of ports 14 at each port 16 in the illustrated embodiment correspond to the bits of a binary number, i.e. to a power (including 0) of the number 2. For example, in the head shown in the figures, there are eight channels having 1, 2, 4, 8, 16, 32, 64, and 128 ports, respectively. This means that by actuation of the valves which selectively couple the ports to the pressure source, it is possible to reduce the pressure at any number of ports from 0 to 255, such that the head 10 can be used to pick up this number of microspheres in one movement. It is of course possible for the number of channels to extend to any number required in order to provide for larger numbers of

microspheres, though in practice it is believed that nine channels should suffice. With the valve position of open corresponding to a binary 1 and closed corresponding to binary 0, the signals used to open the valves will correspond to the number of desired microspheres to be collected, expressed as a binary number. The process of setting the valves correctly may be automated for example by bar code scanning or the like, the input number being indicative of the individual capsule dosage of a required medicine.

Due to the flat shape of the head 10, it may be

beneficial for the canister holding the microspheres prior to collection by the head to be wide and flat such as a tray. Alternatively, the collection surface 12 may be rounded like a cylinder and rotated or rolled over the open canister to reduce its size.

There is a risk of erroneous counting due to moisture or static causing stiction between the microspheres. It is therefore beneficial to provide a way of dislodging from the head microspheres that not held in place against the head by a port under low pressure. This may be achieve by the use of an ultrasonic or other vibrator (not shown) within the counting head or, as shown in figure 2, by a network of independently pressurised jets 18. These jets blow air or inert gas over the microspheres when held in place by the negative pressure source. Their pressure supply and conduit network 20 is therefore independent of that used to retain the microspheres within the ports 14. The intension of this is that, whether combined with the vibration or otherwise, the pressure from the jets 20 serves to dislodge any

undesired microspheres to ensure the correct dosage is transferred to the open capsule.

Once the counting head 10 has collected the correct required number of microspheres they are transported to a discharge funnel to enable them to be ejected directly into an open capsule. The discharge funnel is preferably of the type having a very low coefficient of friction so as to ensure all microspheres slide down into the capsule. Steps may additionally be taken to keep it free of any static charge .

Ejection of the spheres from the head is facilitated by removal of the low (less than atmospheric pressure) pressure supply either by closing of all the valves or by

disconnecting the power to the pump generating the low pressure supply. It is further possible to pressurise the head 10, channels, ports 16 and therefore ports 14 to ensure that each microsphere has been ejected into the discharge funnel .

It may be preferable depending on the nature of the medicines to perform the entire operation of collecting and dispensing the microspheres within a highly controlled environment such as inert gas, or slightly raised pressure. Additionally it may be beneficial to control the humidity and static of the environment to reduce any potential sticking together and/or contamination of the microspheres.

The apparatus 100 shown in Figure 4 uses a stationary head 110 positioned directly above a dispensing funnel 112 that guides the counted microspheres into a capsules halves retained within a holder 114. A carousel 120 rotatable between the head 110 and the funnel 112 has six openings 122, of which five are designed to retain canisters

containing drug microspheres.

In use, the carousel 120 is rotated to bring a canister containing a desired drug below the head 110 and the

appropriate valves connected to the channels in the head 110 are actuating to cause a desired number of microspheres to be picked up. In order to verify that the correct number of microspheres has been picked up by the head, it is possible to view the underside of the head by means of a camera and to determine the number of microspheres by processing the image data gathered by the camera. Once the desired number of microspheres has been picked up by the head, the empty opening is aligned with the head and the microspheres that have been picked up are ejected to fall through the funnel 112 into a capsule. The process is then repeated for the drugs in the other canisters and for each of the capsules in the holder 114.

Once all the capsules in the holder 114 have been filled, a second holder 116 retaining the other capsule halves is placed over the first holder 114 to seal the capsules .

The apparatus 100 incorporates a processor with a display screen 130 to control the above sequence of

operations. The dispensing pharmacist need only enter the number of microspheres of each drug to be contained in each capsule motors for rotating the carousel 120 and the holder 114 are then operated automatically and synchronised with the operation of the valves connected to the channels of the head 110.

By relying on the counting of microspheres, the

illustrated embodiment of the invention provides a

dispensing pharmacist with the facility to mix in one capsule a combination of different active substances in absolute and relative amounts that are specifically

prescribed for the patient by a medical practitioner. Not only can the doses and relative amounts of the active substances be tailored to individual patient requirements in any one set, but the different capsules within a set may contain different doses from one another, enabling a

particular drug to be phased in or out over the period during which the capsules of the set are to be taken by the patient. This is referred to as titration. Such capsules should be prepared and packed in an easily available pack for patients locally in community or hospital pharmacies. It is important for a medical practitioner or a

pharmacist to be able to ascertain the medication previously taken by a patient.

With this aim in mind, it is possible for the capsules, or their packaging if they are blister packed, to be marked with a code that permits the contained active substances and their dosage to be determined.

For proper identification of the capsules, each capsule or more preferably the blister pack containing several capsules may be suitably encoded, for example by means of a bar code or colour coding. The encoded data may be used to identify the dispensing pharmacy, to identify the contained medications, using information stored in a database in the pharmacy.

It is not essential for the code to uniquely identify the contained medications and their dosages. As the

dispensing pharmacy is identified, it suffices for the pharmacy to maintain a register giving more details about the medications and conveniently such data could be accessed directly by medical practitioners and hospitals by using the Internet. Alternatively, the information could be held centrally, allowing access by approved individuals in a secure manner.

As the capsule or dispensing pack codes need not carry individual patient details, confidentiality is preserved. The range of active substances to be formulated in microspheres is potentially wide, but would be most - in ^¬ appropriate where the typical dose ranged from micrograms to tens of milligrams.

The external design of the manufacturers' supply canisters for the microspheres may preferably be of

standardised dimensions and mechanisms for sealing/unsealing and encoding so as to ensure secure mounting into the capsule filling device and to allow positive identification of the contents of the canister through a mechanical/ electrical/radio/magnetic signalling system adopting a standard code.

The internal design characteristics of the

manufacturers' supply canister for the microspheres may be variable to permit adjustment of storage conditions for an adequate shelf life for the individual active substances. For example, the canisters may be filled with an inert gas, masked against entry of light, or coated to prevent water vapour entry.

The external design of the microsphere supply canisters may suitably incorporate a standardised space for labelling giving visual identification and details of contents. Conveniently, the capsule filling device may be

controlled by a computer installation that includes a printer and the computer may be programmed to print labels that give details of the dispensing pharmacy, patient name, active substance, manufacturer, expiry date and

manufacturers' product codes. Such labels may be self adhesive and prepared for attachment to the original

dispensing pack and to the outside of a cardboard box containing treatment supply for a 28 or 30 day period. The original dispensing pack containing the

individually filled capsules should preferably identify capsules for individual days of the week for ease of treatment compliance. Such packs may also conform to

standardised dimensions and carry protrusions and/or

perforations for engagement with the mechanism of an

optional additional device for the extraction of the

capsules from the original dispensing pack at the patient's home .

Two types of extracting device such as described immediately above may be envisaged. The first may be fully automatic, containing original treatment pack for one month's supply of capsules, with ability to present the dose form to the patient at a preset time with audible tone/voice recording/visual alert. The second may be a semi-automatic device for easy removal of the capsule from the original dispensing pack, aiding patients with low sight, reduced manual dexterity or poor memory (prompted by magnifying lens window to view day of the week on the contained original dispensing pack) . The individual components for implementation of the invention may comprise pre-manufactured pharmaceutical capsules which are separated into component halves. The lower-parts may be inserted vertically into strips or wheels which hold twenty eight or fifty six half capsules arranged around the margin of the strip or wheel. The wheel or strip is capable of precision mounting into the capsule-filling device to allow precise filling of capsules with

microspheres. A matching strip or wheel is provided to contain pre-inserted matching top-halves of the capsules. Batch closure of filled capsules is effected by application of opposing strips or wheels containing capsule upper and lower halves.

The capsule halves may be of different colours (e.g. red, orange, yellow, green, light blue, dark blue, brown, black, white, transparent, and they may have superimposed contrasting colour band(s) . In this manner, colour coding may be achieved to allow the origin of the capsules to be identified. Alphanumeric codes may alternatively or

additionally be pre-printed onto one half of capsule (e.g. 10 characters) and such codes may be standardised to enable national identification.

The microsphere canister will typically contain

sufficient spheres for various doses for multiples of twenty eight capsules. Asymmetric shape can be used to ensure standard orientation into the capsule filling device. Labels printed onto the canister can be encoded to allow details of manufacturer, active substance, dose, batch, product licence number and expiry date, to be transferred automatically via a reader in the loading station. The canister is sealed until insertion into the capsule filling device for security against loss of microsphere or contamination of contents.

The capsule filling device should be able to carry plastic strips or wheels containing 28 or 30 capsules and to allow mounting of up to ten manufacturers' canisters of microspheres. The filling device is microprocessor

controlled for accurate dispensing of appropriate numbers of each type of microsphere into each capsule in turn. The microprocessor of the filling device should preferably be able to interface with a pharmacy computer to allow transfer of prescribing information without re-keying of prescription data to the device, and dispatching of securely encoded data to distant secure database via internet connection from the device, via the pharmacy computer. The filling device may also be designed to allow future prescription data entry by barcode read directly off prescription form via the pharmacy computer or downloaded from medical practitioners' systems.

Claims

1. A counting device for collecting a predetermined number of microspheres of a drug from a canister, the device having a head to be placed in use above the microspheres canister, the head comprising a plurality of flow channels each selectively connectable to a low pressure source by means of a valve and being connected to a predetermined number of ports, each port being operative to collect a single microsphere of the drug from the canister when the associated channel is connected to the low pressure source.

2. A counting device as claimed in claim 1, wherein the counting device is a binary counting device, the head having a number of channels each connected to a different number of ports, and the numbers of ports connected to the different channels being different powers of two.

3. A counting device as claimed in claim 2, wherein the head has nine channels and is capable of collecting a total number of microspheres from 0 to 511.

4. A counting device as claimed in any preceding claim, wherein each port comprises a hemispherical cavity having the same radius of curvature as the microspheres, each cavity being in fluid communication with an associated channel .

5. A counting device as claimed in any preceding claim, wherein the channels are selectively connectable to a high pressure source to blow collected microspheres clear of the ports.

6. A counting device as claimed in any preceding claim, further comprising a pressurised source of air controlled independently of the low pressure source for discharging gas under pressure through the head into the drug canister to dislodge from the head any microspheres that are not retained within a port by suction.

7. A counting device as claimed in any preceding claim, further comprising a camera for viewing the underside of the head after microspheres have been collected from a canister and a processor for analysing image data from the camera to verify that the desired number of microspheres has been collected by the head.

8. A method of dispensing a predetermined number of microspheres from a canister using a counting device as claimed in any preceding claim, which method comprises : determining the number of microspheres of a drug required,

positioning the counting head above the canister in proximity to the microspheres,

operating the valves connecting the channels of the head to the low pressure source to such a microsphere into each port in fluid communication with the low pressure source,

positioning the counting head above a dispensing position; and

disconnecting the ports from the low pressure source.

9. A method as claimed in claim 8, wherein the step of disconnecting from the low pressure source includes closing any open valves.

10. A method as claimed in claim 8 or 9, wherein the step of disconnecting from the low pressure source includes connecting the ports to a source of high pressure gas in order to expel any collected microspheres.

11. A method as claimed in any of claims 8 to 10, further comprising the step of blowing a gas over the ports to expel any microspheres not held by suction in a port, prior to moving the counting head to the dispensing

position .

12. A method of filling a pharmaceutical capsule with at least one type of microspheres of an active substance comprising the steps of;

determining the desired dosage of active ingredient required by a patient,

determining the amount of active ingredient in one microsphere,

calculating the number of microspheres required in each capsule to achieve the desired dosage,

counting and collecting the correct number of

microspheres from a canister by the use of a counting device of any of claims 1 to 6,

dispensing the collected microspheres into an open capsule, and

sealing the capsule.