DISPENSING DEVICE

Field of the Invention The present invention relates to devices used for dispensing pharmaceutical compositions to patients in a time-controlled manner.

Background Dispensing pharmaceutical compositions to patients is often complicated by the need to limit the delivery to specific dosing regimens over specific time periods. In the case of many pharmaceuticals, delivery times must be controlled to provide adequate and effective dosing over time, while at the same time preventing inadequate dosing as well as overdosing.

The problem is particularly acute with drugs that demand patient compliance to optimize safety, while maximizing efficacy. Drugs that fall into this class may have strict administration schedules and stringent dosing amounts as exemplified by such classes of molecules to include, but not limited to analgesics, cardiovascular agents, metabolic disorder treatments, and drugs used to treat certain cancers. Such drugs may be subject to overdosing as patients often seek medication prior to the recommended or allowable prescribed dose and schedule, leading to the possibility of adverse events, abuse or fatality.

In supervised healthcare settings, i.e., hospitals, nursing homes, hospices, clinics, and the like, the problem is addressed by enabling healthcare practitioners to dispense fixed amounts of medication for patients at prescribed times in a controlled fashion. In addition, dosing requires the presence of a practitioner to determine, monitor, and sometimes adjust the dosing regimen of the required drug or drugs delivered to the patient in order to optimize efficacy and safety. Such necessary oversight places a large burden on the healthcare provider, as it requires personnel and detailed record-keeping for each patient. Likewise, in less controlled settings, supervision is still required to ensure adequate treatment and to prevent either under or overdosing and/or abuse. A relevant example includes the home healthcare setting, where visiting nurses are often required to be present for the delivery of individual drug doses to patients.

Therefore, a need exists for a user-friendly, simple drug-dispensing device that may contain several doses of a drug, provide individual doses available to a patient at prescribed time intervals, and which moderates some degree of protection to the patient, both by deterring potential over dosage and by making diversion by a family member or other visitor obvious.

Summary and Objects of the Invention

One object of the present invention is to provide a simple device for storing and dispensing prescription drugs. A further object of the present invention is to provide a simple device for storing and dispensing drugs which are administered to a patient via intranasal means.

A further object of the present invention is to provide a simple drug dispensing device that would allow a patient to receive drug doses at prescribed time intervals.

Another object of the present invention is to provide a drug dispensing device that is suitable for use in supervised, semi-supervised, and unsupervised healthcare settings.

Another object of the present invention is to provide a drug dispensing device having indicia thereon to indicate tampering or other attempts to gain unauthorized access to the drugs contained therein.

Still another object of the present invention is to provide a drug dispensing device that can be programmed by a healthcare practitioner to dispense drugs to a patient at prescribed intervals.

Still another object of the present invention is to provide a drug dispensing device that can be programmed by a healthcare practitioner to prevent dispensing drugs to a patient at less than prescribed time intervals. Yet another object of the present invention is to provide a drug dispensing device that would allow patients to self-administer drugs over a prescribed time period.

It is another object of the present invention is to provide a drug dispensing device that would allow patients to self-administer such drugs as analgesics, cardiovascular drugs, drugs used to treat metabolic disorders, and drugs used to treat certain cancers when desired, but no earlier than at prescribed intervals.

It is another object of the present invention to provide a drug dispensing device that can dispense a prescribed drug regimen to a patient at prescribed time intervals.

The above and other objects may be achieved by providing a device for the controlled release of drug delivery units which comprises a magazine for containing a plurality of drug delivery units, a housing containing the magazine having an aperture allowing drug delivery units to be removed from the housing, a link by which the magazine may be moved relative to the housing, and a timing mechanism in communication with the link, for causing the magazine to be moved relative to the housing, thereby periodically allowing removal of individual drug delivery units through the aperture at pre-selected intervals. The device may be configured to allow dispensing of a specified number of drug delivery units over an extended time period, for example 12 or 24 hours or more, or it may be configured to allow dispensing of individual drug delivery units as desired by the patient, provided that the minimum interval between each delivery is of a pre-specified length. The various timing and delivery issues may be controlled by a healthcare provider during loading of the device or at some time thereafter. Certain embodiments of the present invention are directed to devices for the controlled release of drug delivery units where a dose is not wasted if the patient misses that particular dose. In other words, in certain embodiments, the timing mechanism is deactivated until a drug delivery unit is removed from the aperture. In other embodiments where the timing mechanism remains activated, if a dose is missed, that drug delivery unit remains in the magazine and the magazine may move relative to housing to expose the next drug delivery unit. If the magazine does not complete a full cycle so that the missed dose is realigned with the aperture, this dose may become a "wasted dose".

In certain embodiments, the device for the controlled release of drug delivery units includes a door having an open position in which drug delivery units may be removed through the aperture, and a closed position in which drug delivery units are not accessible through the aperture. The timing mechanism may be deactivated when the door is in its open position and the timing mechanism may be activated when the door is in its closed position.

In other embodiments, the device for the controlled release of drug delivery units includes a drug delivery unit detector within the magazine for indicating whether a drug delivery unit is positioned adjacent the aperture. The timing mechanism may be deactivated once the drug delivery unit detector indicates that a drug delivery unit is positioned adjacent the aperture, and the timing mechanism may be activated once the

drug delivery unit detector indicates that a drug delivery unit is not positioned adjacent the aperture.

Various embodiments of the present invention provide certain advantages. Not all embodiments of the invention share the same advantages and those that do may not share them under all circumstances.

Further features and advantages of the present invention, as well as the structure of various embodiments of the present invention are described in detail below with reference to the accompanying drawings.

The above objects and summary of the invention will be more fully set forth in the Figures and detailed description of the invention below.

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Description of the Drawings

The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Various embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: FIG. 1 is a schematic depiction of the device of the present invention. FIGS. 2a and 2b are schematic depictions of intranasal drug delivery units delivered by one embodiment of the present invention.

FIGS. 3a and 3b are schematic top and side views of the base of one embodiment of the present invention.

FIGS. 4a and 4b are schematic top and side views of the housing of one embodiment of the present invention. FIGS. 5a — 5d are schematic top and side views of the magazine of two embodiments of the present invention.

FIGS. 6a and 6b are schematic top and side views of the link of one embodiment of the present invention.

FIG. 7 is a schematic depiction of the timing mechanism of one embodiment of the present invention.

FIG. 8 is a schematic exploded view of another embodiment of a device of the present invention.

FIGS. 9A-9C are schematic front, top and side views of a door according to one embodiment of the present invention.

FIGS. 10A- 1OC are schematic front, top and side views of a door according to another embodiment of the present invention. FIGS. 1 IA-I IB are schematic depictions of another embodiment of a device of the present invention.

FIG. 12 is a schematic depiction of a magazine of one embodiment of the present invention.

Detailed Description

The invention relates broadly to a device for the controlled dispensing of drug delivery units. As used herein, the term "drug delivery unit" is intended to refer to a unit dose of a pharmaceutical composition or an applicator for providing a unit dose of a pharmaceutical composition. Thus, while the term "drug delivery unit" may refer to a pill, tablet, capsule, caplet, etc., (i.e., a unit dose of a pharmaceutical composition) which is ingested by a patient, the term is also intended to refer to a device for delivering a unit dose of a pharmaceutical composition to a patient. Examples herein include, but are not limited to, intranasal applicators, such as applicators designed to deliver a single unit or bidose or multiunit dose of a pharmaceutical composition to a patient. Thus, as will become apparent, the present device may be used to dispense compositions which are ingestible as well as devices for delivering compositions which are administered by means other than ingestion. In one preferred embodiment, the invention is configured to dispense intranasal applicators (such as those manufactured by Ing. Erich Pfeiffer GmbH, Radofzell, Germany; Pfeiffer of America, Princeton, NJ), each loaded with a unit dose of intranasal ketamine, intranasal morphine, or mixtures thereof, either with or without other constituents. Likewise, the invention may be configured to dispense more than one drug delivery unit at any given time, or it may be configured to dispense a drug delivery unit in the form of, for example, a capsule at one or more time intervals and a drug delivery unit in the for of, for example, an intranasal applicator at one or more different time intervals. While the device is intended to be used to dispense any of a wide variety of drug delivery units, it is particularly adapted for dispensing controlled, scheduled drugs in a manner that prevents or provides indicia of overdosing. As noted above, the device is

well-suited for the delivery of intranasal applicators, each loaded with a unit dose of intranasal ketamine, intranasal morphine, or mixtures thereof, either with or without other constituents; however, other drug delivery units are contemplated as well. These include, but are not limited to, the following drugs listed on DEA Schedules II, III, IV and V:

Apart from the above-noted intranasal applicators, each loaded with a unit dose of intranasal ketamine, intranasal morphine, or mixtures thereof, other preferred drug delivery units include unit doses of prescription drugs such as digoxin, β-blockers, α ₂ -

antagonists, thyroid replacement drugs, drugs to treat specific diseases (Alzheimer's, AE)S, diabetes, etc.), anticoagulants, vitamins having potentially toxic overdosages, and any other ingestible, inhalable, injectable or topical drug that is provided according to a scheduled regimen. Other representative drugs include, but are not limited to: betamethasone, budesonide, cortisone, dexamethasone, hydrocortisone, methyl- predinisolone, prednisolone, triamcinolone, capecitabine, chlorambucil, cyclophosphamide, etoposide, hydroxyurea, imatinib, mercaptopurine, methotrexate, buprenorphine, butorphanol, codeine, hydrocodone, hydromorphone, levorphanol, meperidine, methadone, morphine, opium, oxycodone, pentazocine, oxymorphone, anisindione, dicumarol, warfarin, isocarboxazid, phenelzine, tranylcypromine, amitriptyline, amoxaphine, clomipramine, desipramine, doxapin, imipramine, nortriptyline, protriptyline, trimipramine, olanzapine, risperidone, quetiapine, ziprasidone, aripiprazole, clozapine, chlorpromazine, fluphenazine, trifluoperazine, perphenazine, thioridazine, haloperidol, thiothixene, molindone, loxapine, apomorphine, benztropine mesylate, entacapone, levodopa/carbidopa/entacapone, carbidopa/levodopa, pergolide, ropinirole HcI, amantadine HcI, and selegiline HcI.

In other embodiments, representative drugs which may be used include, but are not limited to: branded drugs such as Lanoxin, Decadron, Xeloda, Glivec, Purinethol, Lorcet, Zydone, OxyContin, Endocet, Tylox, Percodan, Darvon, Coumadin, Zyprexa, Symbyax, Seroquel, Geoden, Abilify, Clozaril, Comtan, Stalevo Tablet, Tasmar Tablets, Mirapex Tablets, Permax Tablets, Requip Tablets, Comtan Tablets, and generic drugs such as, Mercaptopurine, Methotrexate, Amitriptyline, Doxepin, Imipramine, Nortripyline, Clozapine/Carbidopa, and Levodopa.

Broadly, in one embodiment, the device is intended to be loaded with multiple doses of one or more drug delivery units and programmed to allow the drug delivery units to be dispensed at predetermined time intervals. In another embodiment, the device is intended to be loaded with multiple doses of one or more drug delivery units and programmed to allow the drug delivery units to be dispensed to a patient when desired, provided that a minimum time interval has passed between dispensing cycles. In another embodiment, patients requiring a regimen of several different drugs over an extended time period may use the device to dispense the particular prescribed multi-drug regimen at specified time periods.

One necessary element of the present invention is a controllable timing mechanism which is in operable communication with a delivery system within the device. While the timing mechanism will be discussed in greater detail below, it is noted that it may be either an electrical or mechanical timing mechanism. Although both offer desired utility, mechanical timing mechanisms offer the advantage of employing the device in the absence of an electrical source.

For dispensing of drug delivery units over a scheduled time period, it is contemplated herein that the timing mechanism may be controlled either by the device manufacturer or at the time it is loaded with the desired drug delivery units. Thus, in one non-limiting example, in which the device is intended to dispense drug delivery units hourly over a 12 hour time period, the timing mechanism may be preprogrammed by the manufacturer. In a further embodiment, the timing mechanism may include a user interface through which a particular dosing and time period may be input. One such non- limiting example would allow a healthcare practitioner to load the device with, for example, 12 doses of intranasal ketamine, and then program the timing mechanism to allow the devise to provide one dose every 2 hours.

Likewise, it is also contemplated that the device may include an interface through which a patient may self-administer drugs on an interval-limited basis. In this embodiment, the device may include a patient dosing interface through which the patient requests a drug delivery unit to be dispensed. The timing mechanism may be programmed by either the manufacturer or a healthcare practitioner to allow drug delivery units to be dispensed freely, provided a minimum interval has passed between each dispensing.

In one embodiment, the dosing of the drug delivery units may be patient controlled and the device may be constructed such that if a patient does not need or desire a particular dose, that particular dose remains accessible to the patient. In other words, in certain embodiments, if a patient has not already taken a scheduled drug delivery unit, that unit will remain accessible to the patient and there is no window of time which will close, thereby preventing the patient from accessing that particular dose.

In one embodiment, the device may be used to simplify a complicated dosing regimen required by a patient. For example, many patients, particularly elderly patients, require doses of several different drugs one or more times per day. Selecting the particular drugs required at particular times can often be complicated or confusing. In one

embodiment, the present invention provides a means by which proper dosing may be simplified. In particular, the device may be loaded in a manner which allows several drug delivery units to be dispensed at one time. As one example, consider the case of a patient requiring drugs A, B, and C every morning, and drugs B and D every evening. The chambers in the magazine of the device may be loaded with alternating combinations of drugs A, B and C and drugs B and D, and the device may be set to dispense the alternating combinations to the patient at twelve hour intervals.

In a preferred embodiment, it is contemplated that the entire device, loaded with the required drug delivery units, may be provided to a patient. This configuration is best applied in situations where the device will be used for short periods, such as for acute post-surgical pain relief. Upon termination of pain medication, the device may be cleaned, loaded with drug delivery units for a different patient, sealed and re-used. Alternatively, in applications in which the device will be used for longer periods, a patient may be provided with a version of the device in which the magazine used to contain drug delivery units is absent. In this case, a healthcare practitioner, pharmacist, or other authorized person may provide a magazine loaded with the appropriate drug delivery units to the patient. Depleted magazines may be either refilled, or replaced with fully loaded units. The device may be best understood from the description below with reference to the accompanying Figures. It should be appreciated that the drawings illustrate various components and features which may be incorporated into various embodiments of the present invention. For simplification, several drawings may illustrate more than one optional feature or component. However, the present invention is not limited to the specific embodiments disclosed in the drawings. It should be recognized that the present invention encompasses embodiments which may include only a portion of the components illustrated in any one figure, and/or may also encompass embodiments combining components illustrated in multiple different drawings, and/or may also encompass embodiments not explicitly disclosed in the drawings.

In one embodiment, shown in FIG. 1, the device 10 comprises a base 12, a housing 14 having an aperture 16 which provides access to the interior of the housing, a magazine 18 for containing drug delivery units and at least one tamper indicia 20. Each of these elements, as well as other device components (not shown in FIG. 1) is described in detail below. The device is well-suited for use with individual intranasal drug delivery units 200

(

(FIG. 2a) and multiple intranasal drug delivery units 202 (FIG. 2b), however, it is not intended to be limited in this manner. Rather, it is contemplated that any of a wide variety of delivery units, including but not limited to, intranasal applicators, pills, capsules, caplets, syringes, inhalers, patches, vials, and the like may be used in connection with the device.

The base 12 of the device is depicted schematically as a top view in FIG. 3a and side view in Fig 3b. In FIGS. 3a and 3b, the base 12 comprises a substantially circular platform 22 containing a central aperture 24. A wall 26 extends downward from the platform 22 periphery to define an interior space below the platform. The interior space communicates with the central aperture 24. Optionally, a plurality of feet 28 may extend from portions of the wall 26 to support the device. In some embodiments, it is desirable to provide the device 10 with tamper indicia 20 which provide evidence of attempts to open the device by unauthorized individuals. While such tamper indicia 20 will be described in greater detail below, in one embodiment, the base 12 may include one or more flanges 30 extending outwardly from the platform. These flanges may contain a bore 32 adapted to mate with similar structures on the housing 14 to provide a means for securing the housing 14 to the base 12 in a manner which would evidence attempts to separate these elements and gain unauthorized access to the device interior.

The housing 14 of the device is depicted schematically as a top view in FIG. 4a and side view in Fig 4b. In FIGS. 4a and 4b, the housing comprises a substantially circular enclosure having a top 34 and a wall 36 extending therefrom. As with the base 12, the housing 14 may include one or more flanges 38 extending outwardly from the housing. These flanges may contain a bore 40 adapted to mate with similar structures on the base 12 to provide a means for securing the housing 14 to the base 12 in a manner which would evidence attempts to separate these elements and gain unauthorized access to the device interior. The wall 36 includes an aperture 42 allowing access to the interior of the housing. The aperture 42 may comprise simply a region on the circumference of the top 34 from which the wall 36 does not extend, or it may be formed as a separate opening in the wall. As discussed in greater detail below, some embodiments may include a door, to cover the aperture to prevent dust and other unwanted substances from entering the device interior. The door may include a simple mechanism that allows it to be opened when a drug delivery unit is available, and closes and optionally locks it when a drug

delivery unit is not available. The aperture 42, with or without the door, must be large enough to allow a drug delivery unit to be removed from the device when it is positioned within the housing 14 adjacent to the aperture 42.

Positioned within the device in the chamber formed between the base 12 and the housing 14 is a magazine 50, shown in FIGS. 5a — 5d. In one embodiment, the magazine may be arranged like a turntable to rotate relative to the housing, whereas in other embodiments, the magazine may move relative to the housing in a linear arrangement. The magazine 50 may include a hub 52 having a link interface 54 and a plurality of partitions 56 extending therefrom. When positioned within the device in the chamber formed between the base 12 and the housing 14, the link interface 54 mates with a link

(described below) and a timing mechanism (described below) to allow the magazine 50 to be rotated within the device. The partitions 56 define storage regions for the drug delivery units and may serve to move the units through the device, toward the aperture 42, as the magazine 50 is rotated in a controlled manner. The hub 52 may contain a drug delivery unit aperture 58 in the regions formed between the partitions to assist in positioning each drug delivery unit within the device. The number of partitions used depends on the particular anticipated dosing regimen with which the device will be used, as well as the particular timing mechanism selected. For example, if the device is intended to dispense 12 drug delivery units over a 24 hour period, the device could have 12 partitions and a 24- hour timing mechanism. As will be apparent from FIGS. 5a and 5b, a magazine having 12 partitions defines 12 storage regions between them. Likewise, in another non-limiting embodiment, shown in FIGS. 5c and 5d, the magazine may include 24 partitions to define 24 storage regions. Such a device could be used to deliver 24 drug delivery units hourly over the course of a day when used with a one-day timing mechanism, or 12 drug delivery units daily over the course of two days when used with a two-day timing mechanism.

Numerous other combinations of timing and dosing regimens will be apparent to those of ordinary skill in the art.

The magazine 50 is rotated within the device using a link 60 shown in FIGS. 6a and 6b. The link 60 comprises, generally, an axle having a magazine interface 62 and a timing mechanism interface 64. The magazine interface 62 mates with the link interface 54 on the magazine 50 to allow the link, when rotated, to rotate the magazine. The timing

mechanism interface 64 mates with a timing mechanism 70, described below, which rotates the link 60 and the magazine 50 in a controlled manner.

In some embodiments, the timing mechanism 70 is configured to move intermittently, whereas in other embodiments, the timing mechanism is configured to move at a constant rate. The constant rate may be slow to provide a large enough window of opportunity for a patient to remove a drug delivery unit from the aperture 42. In other embodiments, the movement of the timing mechanism 70 may be controlled by detectors (discussed below), and in further embodiments, the movement of the timing mechanism 70 may be patient controlled, hi embodiments where the movement of the timing mechanism is patient controlled, the timing mechanism may stop once a drug is ready to be dispensed to a patient. Once the drug is delivered to the patient, the timing mechanism may be reactivated so that another drug will be ready to be dispensed after a predetermined time period. However, in embodiments when the movement of the timing mechanism 70 is patient controlled, the movement may not exceed a maximum dosing regime.

The timing mechanism 70 is depicted schematically in FIG. 7. It is anticipated that any of a wide variety of timing mechanisms may be embodied in the present invention. For example, the timing mechanism may be an electrical timer that is driven by AC current, or it may be an electrical timer that is driven by battery power. In one preferred embodiment, however, the timing mechanism is a mechanical timer. Mechanical timers are preferred because they are simple, durable, reliable and do not require a current source to operate. Thus, the use of a mechanical timer allows the device to be employed in a wide variety of environments where electrical timers would offer little or no usefulness. For example, the device of the present invention is well suited for military applications where AC current may be unavailable. Likewise, the device is suitable for civil defense applications where it may be stored for extended periods of time prior to use. Mechanical timers are unaffected by such storage, whereas batteries may not be reliable in such circumstances.

In one embodiment, the timing mechanism 70 is selected such that it provides the magazine with one complete rotation over a predetermined dosing period. Thus, a "one- day" timing mechanism is one that provides the magazine with one complete rotation over a 24 hour period, a "two-day" timing mechanism is one that provides the magazine with

one complete rotation over a 48 hour period, a "half-day" timing mechanism is one that provides the magazine with one complete rotation over a 12 hour period, etc. The timing device may include a rotating rod 72 that mates with the link 60 via the timing mechanism interface 64. As such, as the rod 72 on the timing mechanism 70 is rotated, it rotates the link 60, which, in turn, rotates the magazine 50.

The timing mechanism 70 may optionally include an audible and/or visual indicator 210 that provides an indication when a drug delivery unit is available for withdrawal from the device. The audible indicia may be, for example, a bell that rings when a dose is available, and the visual indicia may be, for example, a colored segment that becomes visible through the aperture 42 when a dose is available. Thus, in the case of a 12 dose regimen over the course of one day, an audible indicia would sound every two hours. In the embodiment illustrated in FIG. 1, the indicator 210 is on the housing 14, near the aperture 16, however, it should be appreciated that in other embodiments, the indicator 210 may be located differently. As noted in FIGS. 3a and 3b and FIGS. 4a and 4b, the device may include tamper indicia 20. In the embodiments shown, the tamper indicia 20 comprises flanges 30, 38 on the base 12 and the housing 14 each having a bore 32, 40 through which a seal 74 may be inserted. In one preferred embodiment, the seal comprises an electrical tie-wrap which can be formed into a loop using a one-way ratchet mechanism thereon. By inserting tie wraps through the flanges 30, 38 on the base 12 and housing 14, the base and housing are secured together in a manner that prevents unauthorized access to the interior of the device unless the tie wraps are cut.

The device is not intended to be tamper-proof. Rather, the device is intended to provide an indication to a healthcare practitioner that unauthorized access, or attempts at unauthorized access, to the device interior have occurred. It should be understood as well, that any of a wide variety of devices may be used to secure the housing to the base via the flanges. These include dial locks, keyed locks, scored labels and tapes, etc.

In one embodiment of the assembled device, a mechanical timing mechanism is mounted to the underside of the base 12 in a manner such that rotating rod 72 extends through the center of the base 12 and mates with the timing mechanism interface 64 on the link 60. The magazine 50, selected for the particular dosing regimen and loaded with drug delivery units is positioned on the base 12 in a manner such that it mates with the

magazine interface 62 on the link 60. The housing 14 is positioned over this assembly and the tamper indicia 20 is employed to hold the housing to the base. In one preferred embodiment, the drug delivery units comprise intranasal dispensers of analgesic medications intended to be dispensed every two hours over the course of a full day. As such, a one-day timer and a magazine having 12 partitions is employed.

The device above could be stored until needed, and then employed simply by providing it to a patient and activating the mechanical timing mechanism, such as by winding mechanism 220 (FIG. 7). The timing mechanism will begin to rotate the magazine 50 within the device in a manner such that a patient can withdraw one drug delivery unit from the aperture in the housing every two hours. Once a drug delivery unit is removed from the device, another one will not be available until the magazine 50 has rotated sufficiently to make another drug delivery unit available. If the patient attempts to accelerate the dosing by gaining access to the interior of the device, this attempt will be evident via the tamper indicia 20. If the dosing is ¹ intended to be continued over the course of a second day, a healthcare practitioner can open the device, and either reload the magazine or replace it with a preloaded magazine.

In other embodiments of the present invention, individuals may use the device at home to dispense medications according to their particular needs. Thus, a patient taking multiple medications over the course of one or more days may load the magazine, or obtain personalized preloaded magazines, to provide the appropriate medications at the appropriate times.

The individual elements of the device may be made of any of a wide variety of materials. In one preferred embodiment, the base, housing, link and magazine are fabricated from a cast or thermoformed polymer. It is anticipated that the device may be employed in a manner where the elements are reusable, and thus, durable plastics are preferred. In one embodiment, however, the base, housing, timing mechanism and link are intended to be made available as a packaged unit, and the magazine, loaded with the appropriate drug delivery units is obtained separately. In this case, the magazine may be returned during the process of refilling, or it may be discarded. In the latter case, it is preferred that the magazine be formed of a biodegradable or recyclable material. The device of the present invention offers a simple, durable alternative to conventional patient controlled analgesia (PCA) devices. Unlike common PCA systems, a

preferred embodiment the present invention can operate in the absence of electrical power, while providing periodic doses of analgesics in a manner that is tamper evident and self- accounting.

The device lends itself to use in hospitals, semi-supervised care environments, and independent supervised care environments. In post operative patients, the device reduces the cost of care as there is no need for a healthcare practitioner to periodically administer the dispensed medications. For end-of-Iife care, the device can be used to deliver analgesic medications at a greatly reduced cost and improved safety. For settings where the patient needs assistance with determining when to take the medications, i.e., nursing homes, the device reduces the needs for a healthcare practitioner at each dosing event. Finally, in natural disaster or military situations, the device provides a durable means of dispensing medications in environments where electrical power may be unavailable. As mentioned above, in certain embodiments, the timing mechanism may be deactivated when a drug delivery unit is ready to be dispensed. The timing mechanism may not be reactivated until the patient takes the drug. As described in more detail below, in some embodiments, a door is used to control activation of the timing mechanism, and in other embodiments, one or more drug delivery unit detectors 100 may be used to control activation of the timing mechanism.

Turning to FIG. 8, another embodiment of a device 10 for the controlled release of drug delivery units is illustrated. Similar to the device illustrated in FIG. 1, the device 10 in FIG. 8 has a base 12, a housing 14 with an aperture 42 which provides access to the interior of the housing 14, and a magazine 50 for containing drug delivery units. A timing mechanism 70 is provided within the base 12 to move the magazine 50 through link 60. The embodiment illustrated in FIG. 8 also includes a door 90 which may selectively cover the aperture 42. As shown in FIG. 8, the door may have an open position in which drug delivery units may be removed through the aperture 42, and as discussed in greater detail below, the door 90 may also have a closed position in which drug delivery units are not accessible through the aperture 42. The timing mechanism 70 causes the magazine to be moved relative to the housing. In one embodiment, the timing mechanism is deactivated when the door is in its open position and is activated when the door is in its closed position. Thus, in some embodiments, the door 90 may be used to control movement of the magazine 50.

In some embodiments, the door 90 may start out initially in its closed position. Thereafter, the door 90 may open so that a patient may access a drug delivery unit from the magazine 50. Once the door opens 90, the timing mechanism 70 which controls movement of the magazine 50 may be deactivated. The patient is thus permitted to take the drug delivery unit as needed. After the patient takes the drug delivery unit, the patient may close the door 90 to reactive the timing mechanism 70. This reactivation may restart the movement of the magazine so that another drug delivery unit is accessible from the aperture 42 after a pre-determined time period.

In some embodiments, the timing mechanism 70 will not be reactivated until the patient manually closes the door 90. As discussed in greater detail below, in other embodiments, the door may close automatically after a detector indicates that the drug delivery unit was taken. As mentioned above, the timing mechanism 70 may include a visual indicator that provides an indication when a drug delivery unit is available for withdrawal from the device. In one embodiment, the visual indicator may be the opening ofthe door 90.

FIGS. 9A-9C illustrate one embodiment of a door 90 in greater detail and FIGS. 10A- 1OC illustrate another embodiment of a door 92 which may be used to selectively cover the aperture 42.

The open position and the closed position of a door 96 according to one embodiment are shown in greater detail in FIGS. 1 IA-I IB. In FIG. 1 IA, the door 96 is shown in a closed position in which drug delivery units are not accessible through the aperture 42, whereas in FIG. 1 IB, the door 96 is shown in an open position in which drug delivery units may be removed through the aperture 16. It should be appreciated that the door 96 may be formed in a variety of ways, as the invention is not limited in this respect. For example, the door 96 may open along a hinge or it may slide into an open position. Furthermore, in certain embodiments, the door may cover only a portion of the aperture 16.

In some embodiments, the timing mechanism stops once a drug delivery unit is positioned in the magazine for delivery to a patient. For example, in one embodiment, the timing mechanism stops once a drug delivery unit is positioned adjacent the aperture 16. The timing mechanism may remain in a stopped or deactivated state until the drug delivery unit is taken by the patient. In this respect, the drug delivery unit does not

become a "wasted dose" if the patient does not take the drug within a certain period of time. In one embodiment, the timing mechanism may be started or reactivated when a drug delivery unit is no longer adjacent the aperture 16 (i.e. once the drug delivery unit is removed from the magazine). As discussed in more detail below, in some embodiments, one or more detectors 100 may be used to indicate whether or not a drug delivery unit has been taken by a patient. In some embodiments, the timing mechanism may be configured such that it automatically stops after a drug delivery unit is positioned to be taken by a patient. For example, when the magazine moves relative to the housing by rotation, the timing mechanism may be configured to move one interval (i.e. 30° when the magazine has 12 storage regions) and then stop until the drug delivery unit is taken from the magazine.

As shown in FIG. 1 IB ₅ in some embodiments, the device may include a drug delivery unit detector 100 within the magazine for indicating whether a drug delivery unit is positioned adjacent the aperture 16. In this embodiment, the timing mechanism 70 may be deactivated once the drug delivery unit detector 100 indicates that a drug delivery unit is positioned adjacent the aperture 16. The timing mechanism may then be activated once said drug delivery unit detector 100 indicates that a drug delivery unit is not positioned adjacent the aperture 16. In one embodiment having a door 96 to selectively cover the aperture 16, the door may automatically close after the detector 100 indicates that the drug delivery unit was taken.

In the particular embodiment illustrated in FIG. HB, the detector 100 is a mechanical detector, such as a push-button. In this embodiment, the button is depressed when a drug delivery unit is positioned on the button which is adjacent the aperture 16. When a patient takes the drug delivery unit through the aperture 16, the push-button may no longer be depressed, thereby mechanically detecting that the drug delivery unit is no longer positioned adjacent the aperture 16. This may trigger the activation of the timing mechanism 70 such that another drug delivery unit may be dispensed after a predetermined period of time based on the dosage.

In other embodiments, a plurality of drug delivery detectors 100 may be provided. For example, in the embodiment illustrated in FIG. 12, the drug delivery unit detector includes a plurality of detectors 100 spaced about the magazine 50. In this particular embodiment, a detector 100 is positioned in each storage region which is defined by

partitions. In one embodiment, one or more of the detectors 100 may be a lever. In such an embodiment, the detector 100 may sense the presence of a drug delivery unit when a unit is on the lever, whereas the position of the lever may change when the unit is taken out of the magazine. It is also contemplated that in some embodiments, the drug delivery unit detector may include electronic sensors to indicate the presence of a drug delivery unit. Furthermore, it is also contemplated that in embodiments featuring an aperture 58 in the hub 52, the detector 100 may be positioned within one or more apertures 58.

Equivalents

The present invention is not intended to be limited in scope by the specific embodiments described herein, each of which is presented by way of example only. Various modifications of the invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and the accompanying figures. Such modifications are intended to fall within the scope of the claims.