Patent Application
20220362464
The present invention relates generally to delivery of a therapeutic substance to a subject, and more specifically to wearable drug delivery devices.
Pumps are often used in the medical industry for delivering therapeutic substances, e.g., drugs, to subjects. Therapeutic substances such as saline solution, insulin, antibiotics, and chemotherapy drugs may all be delivered to a subject with medical pumps. While hospitalization is required for delivery of some therapeutic substances, other therapeutic substances, such as for example insulin, do not require that the subject be in the hospital. Wearable medical pumps enable patients to go about their daily lives while receiving a therapeutic substance.
A therapeutic substance delivery apparatus, such as a wearable medical patch pump, is provided for delivering a therapeutic substance to a subject. The therapeutic substance delivery apparatus includes a housing, a reservoir disposed at least partially within the housing, and a plunger that is slidable within the reservoir. The therapeutic substance delivery apparatus is typically packaged for commercial sale with the reservoir empty and the apparatus accompanied by a syringe containing a volume of the therapeutic substance. The housing of the therapeutic substance delivery apparatus is typically shaped to define a filling port that is in fluid communication with the reservoir and through which the reservoir is filled with the therapeutic substance from the syringe. In preparation for delivery of the therapeutic substance to the subject, a user, e.g., the subject who will receive the medication, a pharmacist, or a caregiver, fills the reservoir with a volume of therapeutic substance, e.g., a prescribed volume of therapeutic substance.
When the reservoir is empty, the plunger typically resides at a proximal end of the reservoir. As used herein, including in the claims, the proximal end of the reservoir is the end that is closest to the filling port, at which the plunger resides when the reservoir is empty, and to which the plunger returns once the contents of the reservoir have been delivered. As the reservoir is filled via the filling port, the plunger is pushed distally within the reservoir toward a distal end of the reservoir. As used herein, including in the claims, the distal end of the reservoir is the end that is furthest from the filling port, and to which the plunger slides as the reservoir is being filled.
Thus, during operation of the therapeutic substance delivery apparatus, the position of the plunger within the reservoir can provide information regarding the filling of the reservoir and subsequent delivery of the therapeutic substance from the reservoir to the subject. In accordance with some applications of the present invention, in order to monitor the filling of the reservoir and subsequent delivery of the therapeutic substance from the reservoir to the subject, the therapeutic substance delivery apparatus typically has a position sensor having at least three states, and a plunger-sensor engagement interface that is coupled to the plunger within the reservoir and extends from within the reservoir to outside of the reservoir in order to engage the position sensor. The plunger and the position sensor are arranged such that the plunger-sensor engagement interface causes the position sensor to change states as the plunger slides within the reservoir. Control circuitry of the therapeutic substance delivery apparatus identifies new state indications of the apparatus, including for some applications, errors associated with filling and/or delivery, based on (a) a change in state of the position sensor, or (b) a previous or current state of the apparatus in combination with a threshold amount of time having elapsed without the position sensor changing state.
There is therefore provided, in accordance with some applications of the present invention, a therapeutic substance delivery apparatus including:
a housing;
a reservoir disposed at least partially within the housing and configured to hold a therapeutic substance;
a position sensor having at least three states;
a plunger, slidable within the reservoir;
a plunger-sensor engagement interface that is coupled to the plunger within the reservoir and extends from within the reservoir to outside of the reservoir, the plunger and the position sensor being arranged such that the plunger-sensor engagement interface causes the position sensor to change states as the plunger slides within the reservoir; and
control circuitry configured to identify a new state indication of the apparatus based on (a) a change in state of the position sensor, or (b) a previous or current state of the apparatus in combination with a threshold amount of time having elapsed without the position sensor changing state.
For some applications, the position sensor has at least three discrete states.
For some applications, the position sensor has exactly three discrete states.
For some applications, the plunger and the position sensor are arranged such that distal movement of the plunger from an initial proximal position within the reservoir to an intermediate position within the reservoir causes the plunger-sensor engagement interface to change the state of the position sensor from a first state of the discrete states to a second state of the discrete states.
For some applications, the plunger and the position sensor are arranged such that distal movement of the plunger from the initial proximal position less than 0.5 mm toward the intermediate position does not cause the plunger-sensor engagement interface to change the state of the position sensor from the first state to the second state.
For some applications, the plunger and the position sensor are arranged such that distal movement of the plunger past the intermediate position to a post-intermediate position within the reservoir causes the plunger-sensor engagement interface to change the state of the position sensor from the second state back to the first state.
For some applications, the post-intermediate position is at least 0.1 mm distal to the intermediate position.
For some applications, the plunger and the position sensor are arranged such that, subsequently to the position sensor changing from the second state back to the first state, proximal movement of the plunger within the reservoir causes the plunger-sensor engagement interface to change the state of the position sensor from the first state to a third state of the discrete states.
For some applications, the plunger and the position sensor are arranged such that, subsequently to the position sensor changing from the first state to the third state, further proximal movement of the plunger causes the plunger-sensor engagement interface to change the state of the position sensor from the third state back to the first state.
For some applications, the apparatus is in a sleep state when packaged for commercial sale, and the position sensor is in a first state S1 when the apparatus is in the sleep state.
For some applications, the control circuitry is configured to (a) identify that the apparatus is in an expired state if a sleep-threshold amount of time has elapsed without the position sensor changing state from S1, and (b) in response thereto, disable the apparatus.
For some applications, the housing is shaped to define a filling port in fluid communication with the reservoir, and the reservoir is configured to be filled with the therapeutic substance via the filling port.
For some applications:
(a) prior to the filling of the reservoir the apparatus is in a sleep state, the plunger is disposed at an initial proximal position within the reservoir, and the position sensor is in a first state S1,
(b) filling the reservoir with the therapeutic substance causes the plunger to slide in a distal direction from the initial proximal position,
(c) the plunger and the position sensor are arranged such that as the plunger slides in the distal direction, the plunger-sensor engagement interface causes the position sensor to change state from S1 to a second state S2, and
(d) the control circuitry is configured to identify that the apparatus is awake and in a filling state in response to the position sensor changing state from S1 to S2.
For some applications, the plunger and the position sensor are arranged such that as the plunger slides distally from the initial proximal position, an initial volume of the therapeutic substance enters the reservoir prior to the plunger-sensor engagement interface causing the position sensor to change state from S1 to S2.
For some applications:
the plunger and the position sensor are arranged such that upon completion of the reservoir being filled with a threshold volume of the therapeutic substance, the plunger-sensor engagement interface causes the position sensor to change state from S2 back to S1, and
the control circuitry is configured to identify that a filling error has occurred in response to (i) the state of the apparatus being filling, in combination with (ii) a filling-threshold amount of time having elapsed from when the position sensor changes state from S1 to S2 without the position sensor changing state from S2 back to S1.
For some applications, the plunger and the position sensor are arranged such that upon completion of the reservoir being filled with at least a threshold volume of the therapeutic substance, the plunger-sensor engagement interface causes the position sensor to change state from S2 back to S1, and the control circuitry is configured to identify that the apparatus is in a filling-complete state in response to the position sensor changing state from S2 back to S1.
For some applications, the plunger and the position sensor are arranged such that, subsequently to the plunger-sensor engagement interface causing the position sensor to change state from S1 to S2, the plunger-sensor engagement interface maintains engagement with the position sensor, so as to maintain the position sensor in state S2, until the reservoir has been filled with the threshold volume of the therapeutic substance.
For some applications, the plunger and the position sensor are arranged such that further distal movement of the plunger subsequently to the reservoir being filled with the threshold volume of the therapeutic substance causes the plunger-sensor engagement interface to terminate engagement with the position sensor, causing the position sensor to switch from S2 back to S1.
For some applications, a distance between two fixed points of the plunger-sensor engagement interface determines when the plunger-sensor engagement interface terminates engagement with the position sensor.
For some applications:
(a) upon completion of the reservoir being filled with at least a threshold volume of the therapeutic substance, the apparatus is in a filling-complete state, and the position sensor is in state S1,
(b) subsequently to the apparatus being in the filling-complete state, the control circuitry is configured to initiate a delivery-started state of the apparatus in which the control circuitry drives the therapeutic substance delivery apparatus to deliver the therapeutic substance from the reservoir to a subject by driving the plunger to slide proximally within the reservoir, and
(c) the plunger and the position sensor are arranged such that as the plunger slides proximally the plunger-sensor engagement interface causes the position sensor to change state from S1 to a third state S3.
For some applications, the control circuitry is configured to identify that there is a leak in the reservoir in response to the position sensor changing state from S1 to S3 prior to the control circuitry initiating the delivery-started state of the apparatus, and in response to the identification that there is a leak, disable the apparatus.
For some applications, the control circuitry is further configured to (a) receive an input indicating an intended volume of the therapeutic substance to be filled within the reservoir, and (b) in response to the received input, determine the length of an expected wait-time between the control circuitry initiating the delivery-started state of the apparatus and the plunger-sensor engagement interface causing the position sensor to change state from S1 to S3.
For some applications, the control circuitry is configured to:
in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) the position sensor changing state from S1 to S3 prior to the expected wait-time having elapsed, terminate the delivery of the therapeutic substance to the subject.
For some applications, the control circuitry is configured to identify that the reservoir has been filled with a volume of therapeutic substance that is larger than the intended volume in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) the position sensor changing state from S1 to S3 after an amount of time that is longer than the expected wait-time but shorter than a delivery-start-threshold amount of time.
For some applications, the control circuitry is configured to terminate the delivery of the therapeutic substance to the subject in response to the reservoir having been filled with the volume of therapeutic substance larger than the intended volume.
For some applications, the control circuitry is configured to compensate for the difference in volume between the intended volume and the volume of therapeutic substance within the reservoir that is larger than the intended volume by terminating the delivery of the therapeutic substance to the subject upon delivering the intended volume to the subject.
For some applications:
(a) the plunger and the position sensor are arranged such that, in response to the reservoir being filled with the intended volume, upon delivering the intended volume to the subject the plunger-sensor engagement interface causes the position sensor to change state from S3 back to S1, and
(b) in response to the identification that the reservoir has been filled with a volume of therapeutic substance that is larger than the intended volume, upon delivering the intended volume to the subject, the control circuitry is configured to terminate the delivery of the therapeutic substance to the subject notwithstanding the position sensor remaining in state S3.
For some applications, the control circuitry is configured to:
identify that a delivery-start error has occurred in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) a delivery-start-threshold amount of time having elapsed from when the control circuitry initiated the delivery-started state without the position sensor changing state from S1 to S3, and
in response thereto, disable the apparatus.
For some applications, the control circuitry is configured to identify that the apparatus is in a delivery-in-progress state, in which therapeutic substance is being delivered from the reservoir to the subject, in response to the position sensor changing state from S1 to S3 subsequently to the control circuitry initiating the delivery-started state of the apparatus and the expected wait-time having elapsed.
For some applications, the plunger and the position sensor are arranged such that upon completion of delivery of the intended volume of therapeutic substance from the reservoir, the plunger-sensor engagement interface causes the position sensor to change state from S3 back to S1, and the control circuitry is configured to identify that the apparatus is in a delivery-complete state in response to the position sensor changing state from S3 to S1.
For some applications, the control circuitry is configured to identify that a delivery-progress error has occurred in response to (i) the current state of the apparatus being delivery-in-progress, in combination with (ii) a delivery-progress-threshold amount of time having elapsed from when the position sensor changes state from S1 to S3 without the position sensor changing state from S3 back to S1.
For some applications, the apparatus is configured such that when the reservoir is in a filled state in which a volume of therapeutic substance is disposed within the reservoir and the position sensor is in a first state S1:
(a) the control circuitry is configured to initiate a delivery-started state of the apparatus in which the control circuitry drives the therapeutic substance delivery apparatus to deliver the therapeutic substance from the reservoir to a subject by driving the plunger to slide proximally within the reservoir, and
(b) the plunger and the position sensor are arranged such that as the plunger slides proximally, the plunger-sensor engagement interface causes the position sensor to change state from S1 to a post-first state.
For some applications, the control circuitry is configured to identify that there is a leak in the reservoir in response to the position sensor changing state from S1 to the post-first state prior to the control circuitry initiating the delivery-started state of the apparatus.
For some applications, the control circuitry is further configured to (a) receive an input indicating an intended volume of the therapeutic substance, and (b) in response to the received input determine the length of an expected wait-time between the control circuitry initiating the delivery-started state of the apparatus and the plunger-sensor engagement interface causing the position sensor to change state from S1 to the post-first state.
For some applications, the control circuitry is configured to terminate the delivery of the therapeutic substance to the subject in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) the position sensor changing state from S1 to the post-first state prior to the expected wait-time having elapsed.
For some applications, the control circuitry is configured to identify that the volume of therapeutic substance within the reservoir was larger than the intended volume in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) the position sensor changing state from S1 to S3 after an amount of time that is longer than the expected wait-time but shorter than a delivery-start-threshold amount of time.
For some applications, the control circuitry is configured to terminate the delivery of the therapeutic substance to the subject in response to the reservoir having been filled with the volume of therapeutic substance larger than the intended volume.
For some applications, the control circuitry is configured to compensate for the difference in volume between the intended volume and the volume of therapeutic substance within the reservoir that was larger than the intended volume by terminating the delivery of the therapeutic substance to the subject upon delivering the intended volume to the subject.
For some applications:
(a) the plunger and the position sensor are arranged such that, in response to the reservoir being filled with the intended volume, upon delivering the intended volume to the subject the plunger-sensor engagement interface causes the position sensor to change state from S3 back to S1, and
(b) in response to the identification that the reservoir has been filled with a volume of therapeutic substance that is larger than the intended volume, upon delivering the intended volume to the subject, the control circuitry is configured to terminate the delivery of the therapeutic substance to the subject notwithstanding the position sensor remaining in state S3.
For some applications:
the control circuitry is configured to identify that a delivery-start error has occurred in response to (i) the current state of the apparatus being delivery-started, in combination with (ii) a delivery-start-threshold amount of time having elapsed from when the control circuitry initiated the delivery-started state without the position sensor changing state from S1 to the post-first state, and
in response thereto, terminate the delivery of the therapeutic substance to the subject.
For some applications, the control circuitry is configured to identify that the apparatus is in a delivery-in-progress state, in which therapeutic substance is being delivered from the reservoir to the subject, in response to the position sensor changing state from S1 to the post-first state subsequently to the control circuitry initiating the delivery-started state of the apparatus and the expected wait-time having elapsed.
For some applications, the plunger and the position sensor are arranged such that upon completion of delivery of the intended volume of therapeutic substance from the reservoir, the plunger-sensor engagement interface causes the position sensor to change state from the post-first state back to S1, and the control circuitry is configured to identify that the apparatus is in a delivery-complete state in response to the position sensor changing state from the post-first state back to S1.
For some applications, the control circuitry is configured to identify that a delivery-progress error has occurred in response to (i) the current state of the apparatus being delivery-in-progress, in combination with (ii) a delivery-progress-threshold amount of time having elapsed from when the position sensor changes state from S1 to the post-first state without the position sensor changing state from the post-first state back to S1.
The present invention will be more fully understood from the following detailed description of applications thereof, taken together with the drawings, in which:
Reference is now made to
A plunger-sensor engagement interface 28, e.g., a rigid protrusion, is coupled to plunger 26 within reservoir 22 and extends from within reservoir 22 to outside of reservoir 22 so as to engage with a position sensor 30, e.g., a microswitch, an optical sensor, a magnetic sensor, or an inductive sensor. It is noted that in the case of a magnetic or inductive sensor, plunger-sensor engagement interface 28 includes a magnet or metal portion. Position sensor 30 has at least three states, further described hereinbelow, e.g., at least three discrete states, e.g., exactly three discrete states. Plunger 26 and position sensor 30 are arranged such that plunger-sensor engagement interface 28 causes position sensor 30 to change states as plunger 26 slides within reservoir 22, further described hereinbelow.
As described hereinbelow, control circuitry 32 monitors the state of therapeutic substance delivery apparatus 20 and receives input signals from position sensor 30 corresponding to which state position sensor 30 is in and, for some applications, an amount of time that has elapsed since position sensor 30 last changed state. In response thereto, control circuitry 32 is configured to identify a new state indication of therapeutic substance delivery apparatus 20 based on (a) a change in state of position sensor 30, or (b) a previous or current state of therapeutic substance delivery apparatus 20 in combination with a threshold amount of time having elapsed without position sensor 30 changing state.
It is noted that throughout the present application, reference is continuously made to the numbered lines of the state table in
It is noted that the terms “first state,” and “S1” are used interchangeably throughout the present application, including in the claims, and refer to a neutral state of position sensor 30 in which plunger-sensor engagement interface 28 is not in engagement with position sensor 30. This is depicted by the horizontal line extending from position sensor 30 in segments (1-2) and (5) of
It is noted that the terms “second state,” and “S2” are used interchangeably throughout the present application, including in the claims, and refer to a state of position sensor 30 in which plunger-sensor engagement interface 28 is engaged with position sensor 30 as plunger 26 slides distally within reservoir 22. This is depicted by the upwards-slanted line (to the upper left) extending from position sensor 30 in segment (3-4) of
It is noted that the terms “third state,” “S3,” and “post-first state” are used interchangeably throughout the present application, including in the claims, and refer to a state of position sensor 30 in which plunger-sensor engagement interface 28 is engaged with position sensor 30 as plunger 26 slides proximally within reservoir 22. This is depicted by the downwards-slanted line (to the lower left) extending from position sensor 30 in segment (6) of
Reference is now made specifically to segments (1-2) and (3-4) of
Therapeutic substance delivery apparatus 20 is typically in a sleep state, with reservoir 22 empty, when packaged for commercial sale. In the sleep state, position sensor 30 is in state S1. This corresponds to line 1 of the state table of
For some applications, control circuitry 32 is configured to identify that therapeutic substance delivery apparatus 20 has expired if a sleep-threshold amount of time has elapsed without position sensor 30 changing state from S1. This corresponds to line 2 of the state table of
For some applications, the sleep-threshold amount of time is programmed into therapeutic substance delivery apparatus 20 during manufacturing and relates to a shelf-life of therapeutic substance delivery apparatus 20 itself, regardless of an expiration date of the particular therapeutic substance being used with therapeutic substance delivery apparatus 20. For some applications, the shelf-life of therapeutic substance delivery apparatus 20 may be longer than the expiration date of the particular therapeutic substance. For some applications, control circuitry 32 is configured to receive an input, via a user interface, indicating an updated sleep-threshold amount of time that corresponds to the expiry date of the particular therapeutic substance being used with therapeutic substance delivery apparatus 20. Examples of the user interface may be a control panel on therapeutic substance delivery apparatus 20 itself, or an application on a wireless device such as a phone or tablet.
In order to account for tolerances within therapeutic substance delivery apparatus 20, e.g., tolerances in the sensitivity of position sensor 30, and tolerances in position and size of plunger-sensor engagement interface 28, plunger 26 and position sensor 30 are arranged such that as plunger 26 slides distally in response to filling, there is a distance D1 that plunger 26 must traverse before plunger-sensor engagement interface 28 causes position sensor 30 to switch states from S1 to S2. As such, as plunger 26 slides distally from initial proximal position P1, an initial volume of the therapeutic substance enters reservoir 22 prior to plunger-sensor engagement interface 28 causing position sensor 30 to change state from S1 to S2. Distance D1 thus prevents therapeutic substance delivery apparatus 20 from accidentally waking up before reservoir 22 is actually being filled with the therapeutic substance.
Distance D1 is depicted in segment (3-4) of
Reference is now made specifically to segments (3-4) and (5) of
For some applications, control circuitry 32 monitors the filling of reservoir 22 so as to identify when therapeutic substance delivery apparatus 20 has reached a filling-complete state. In this case, plunger 26 and position sensor 30 are arranged such that distal movement of plunger 26 past intermediate position P2 to a post-intermediate position P3 within reservoir 22 causes plunger-sensor engagement interface 28 to change the state of position sensor 30 from S2 back to S1. Post-intermediate position P3 is illustrated by the dashed line labeled P3 spanning segments (3-4) and (5) of
For some applications, plunger 26 and position sensor 30 are arranged such that, subsequently to plunger-sensor engagement interface 28 causing position sensor 30 to change state from S1 to S2 (i.e., waking up therapeutic substance delivery apparatus 20), plunger-sensor engagement interface 28 maintains engagement with position sensor 30, thereby maintaining position sensor 30 in state S2, until reservoir 22 has been filled with the threshold volume of the therapeutic substance. Further distal movement of plunger 26 subsequently to the reservoir being filled with the threshold volume of the therapeutic substance, i.e., plunger 26 reaching post-intermediate position P3, causes plunger-sensor engagement interface 28 to terminate engagement with position sensor 30, causing position sensor 30 to switch states from S2 back to S1.
For some applications, a dimension of plunger-sensor engagement interface 28 determines how long plunger-sensor engagement interface 28 maintains engagement with position sensor 30, i.e., a distance D3 between two fixed points on plunger-sensor engagement interface 28 determines when plunger-sensor engagement interface 28 terminates engagement with position sensor 30. In order to ensure that upon completion of filling reservoir 22 with the threshold volume of the therapeutic substance position sensor 30 does indeed switch states from S2 back to S1, tolerances within therapeutic substance delivery apparatus 20 should be accounted for, e.g., tolerances in the sensitivity of the microswitch. This is achieved by a distance D2 between intermediate position P2 and post-intermediate position P3 being large enough, e.g., at least 0.1 mm, so as to ensure that plunger-sensor engagement interface 28 terminates engagement with position sensor 30 upon plunger 26 reaching post-intermediate position P3. This is depicted as well by dashed line 36 spanning segments (3-4) and (5) of
In the event that a filling error occurs, e.g., plunger 26 gets stuck and is unable to move distally in order to accommodate the incoming therapeutic substance, or the user stops filling in the middle, control circuitry 32 is able to identify that a filling error has occurred in response to (i) the state of therapeutic substance delivery apparatus 20 being filling (as previously identified by the switch of position sensor 30 from S1 to S2), in combination with (ii) a filling-threshold amount of time having elapsed from when position sensor 30 changes state from S1 to S2 without position sensor 30 changing state from S2 back to S1. This corresponds to line 4 of the state table of
For some applications, in the event of a filling error, therapeutic substance delivery apparatus 20 provides an alert and then disables itself such that delivery of the therapeutic substance does not begin. Alternatively or additionally, for some applications, in the event of a filling error, therapeutic substance delivery apparatus 20 provides an alert to the user that filling of the reservoir is not complete and allows the user to resume filling reservoir 22. Subsequently, if the fill-threshold amount of time (or another amount of time) elapses again without position sensor 30 changing state from S2 back to S1, therapeutic substance delivery apparatus 20 disables itself.
Reference is now made specifically to segment (6) of
Typically, as described hereinabove, upon completion of reservoir 22 being filled with at least the threshold volume of the therapeutic substance, therapeutic substance delivery apparatus 20 is in a filling-complete state, and position sensor 30 is in state S1, as depicted in segment (7) of
As illustrated in segment (5) of
Control circuitry 32 is configured to identify that therapeutic substance delivery apparatus 20 is in a delivery-in-progress state, in which therapeutic substance is being delivered from reservoir 22 to the subject, in response to position sensor 30 changing state from S1 to S3 subsequently to control circuitry 32 initiating the delivery-started state of therapeutic substance delivery apparatus 20 and the expected wait-time having elapsed. This corresponds to line 8 of the state table of
Typically, part of the process of initiating the delivery-started state of therapeutic substance delivery apparatus 20 is to fluidly connect reservoir 22 to the fluid path through which the therapeutic substance is delivered to the subject. This is done by control circuitry 32 activating a needle slider to drive a fluid path needle 38 into the proximal end of reservoir 22 (e.g., using techniques and apparatus described in US Patent Application Publication US 2020/0108201 to Ben David et al., which is incorporated herein by reference). As shown in
As described hereinabove, one undesired way in which therapeutic substance may leave reservoir 22 subsequently to reservoir 22 having been filled is if there is a leak in reservoir 22. Control circuitry 32 is configured to identify that there is a leak in reservoir 22 in response to position sensor 30 changing state from S1 to S3 prior to control circuitry 32 initiating the delivery-started state of therapeutic substance delivery apparatus 20. Typically, in response to the identification that there is a leak, control circuitry 32 disables therapeutic substance delivery apparatus 20. This corresponds to line 6 of the state table of
As described hereinabove, post-intermediate position P3 corresponds to the threshold volume of therapeutic substance that has to be filled within reservoir 22 in order for control circuitry 32 to identify that therapeutic substance delivery apparatus 20 is in a filling-complete state. However, for many therapeutic substances, different patients will be prescribed different dosages of therapeutic substance to be delivered, e.g., based on a subject's weight, or severity of condition. Typically, therapeutic substance delivery apparatus 20 is configured such that the threshold volume of therapeutic substance needed in order for control circuitry 32 to identify the filling-complete state corresponds to a minimum reasonable dosage that may be prescribed for a given therapeutic substance being administered by therapeutic substance delivery apparatus 20. At the manufacturing stage, therapeutic substance delivery apparatus 20 may be configured for a specific therapeutic substance. For example, distance D3, which determines when plunger-sensor engagement interface 28 terminates engagement with position sensor 30 during filling, may be configured to correspond to a specific threshold volume for a particular therapeutic substance.
Segment (7) of
For some applications, a given subject may be prescribed a volume of therapeutic substance that is larger than the threshold volume. For some applications, therapeutic substance delivery apparatus 20 is packaged for commercial sale including a syringe that holds a standard volume of therapeutic substance, e.g., 10 ml, regardless of how much therapeutic substance a particular subject is supposed to receive. If a given subject is prescribed a volume of therapeutic substance that is larger than the threshold volume, then upon completion of the subject filling reservoir 22 with the prescribed volume, plunger-sensor engagement interface 28 is positioned distal to position sensor 30 by a distance that is larger than D4. As such, plunger 26 has to traverse this larger distance in the proximal direction before plunger-sensor engagement interface 28 causes position sensor 30 to change states from S1 to S3. Therefore, the inventors have realized that in order to accommodate therapeutic substance delivery apparatus 20 being usable with various different dosages of a therapeutic substance, control circuitry 32 is configured to (a) receive an input indicating an intended volume of the therapeutic substance to be filled within reservoir 22, and (b) in response to the received input, determine the length of the expected wait-time between control circuitry 32 initiating the delivery-started state of the apparatus and plunger-sensor engagement interface 28 causing position sensor 30 to change state from S1 to S3.
For some applications, control circuitry 32 receives the input indicating the intended volume of therapeutic substance to be filled within reservoir 22 during the manufacturing processes of therapeutic substance delivery apparatus 20. For example, software may be downloaded to therapeutic substance delivery apparatus 20 to preprogram therapeutic substance delivery apparatus 20 for a specific intended volume of therapeutic substance. In this case, there may be several different configurations of therapeutic substance delivery apparatus 20 that are sold commercially, and a subject will be prescribed a device that corresponds to a specific prescribed dosage of therapeutic substance.
Additionally or alternatively, therapeutic substance delivery apparatus 20 may be sold having a certain configuration, e.g., preconfigured for the threshold volume of therapeutic substance, and may then be reconfigured via a user interface through which control circuitry 32 receives the input indicating the intended volume of therapeutic substance. For example, the user, e.g., the subject who receives the therapeutic substance, a pharmacist, or caregiver, may configure the device according to the prescribed amount of therapeutic substance. Examples of the user interface may be a control panel on therapeutic substance delivery apparatus 20 itself, or an application on a wireless device such as a phone or tablet.
Segment (7′) in
Due to reservoir 22 being filled with therapeutic substance by a user of therapeutic substance delivery apparatus 20, e.g., the subject, a pharmacist, or a caregiver, there is a margin for human error. For example, it is possible that a user may accidentally fill reservoir 22 with a volume of therapeutic substance that surpasses the threshold volume, but that is less than or greater than the intended volume. In this case, due to plunger 26 having reached post-intermediate position P3 (once the threshold volume has been filled), control circuitry 32 identifies that filling is complete (line 5 of the state table) and may initiate the delivery-started state of therapeutic substance delivery apparatus 20 despite the wrong volume of therapeutic substance having been filled within reservoir 22. Additionally or alternatively, if reservoir 22 has a leak in it then even if the user correctly fills reservoir 22 with the intended volume, some therapeutic substance may exit reservoir 22 causing plunger 26 to slide proximally within reservoir 22.
The inventors have realized that control circuitry 32 having received the input indicating the intended volume, and having determined a corresponding expected wait time, allows control circuitry 32 to identify if reservoir 22 is not holding the correct, i.e., intended, volume of therapeutic substance. Position sensor 30 is expected to switch states from S1 to S3 after the expected wait-time corresponding to distance D5 has elapsed. As further described hereinbelow with reference to segments (7″) and (7′″) of
Segment (7″) of
Segment (7′″) of
For some applications, control circuitry 32 terminates delivery of the therapeutic substance to the subject in response to reservoir 22 having been filled with the volume of therapeutic substance that is larger than the intended volume. Alternatively, control circuitry 32 may compensate for the difference in volume between the intended volume and the larger volume by terminating the delivery of the therapeutic substance upon delivering the intended volume to the subject, notwithstanding there being extra therapeutic substance within reservoir 22. Typically, delivery of the therapeutic substance to the subject is driven by an electromechanical pumping assembly (e.g., using techniques and apparatus described in US Patent Application Publications US 2019/0365985 to Zidon et al. and US 2020/0108201 to Ben David et al., which are incorporated herein by reference). The electromechanical pumping assembly typically includes a motor, e.g., a stepper motor, and control circuitry 32 is able to monitor how much therapeutic substance has been delivered to the subject by monitoring the pumping cycles of the electromechanical pumping assembly, e.g., by monitoring the motor. This allows control circuitry 32 to terminate the delivery upon the intended volume of therapeutic substance having been delivered to the subject.
Typically, under normal operating conditions where reservoir 22 is filled with the intended volume of therapeutic substance, plunger 26 and position sensor 30 are arranged such that upon completion of delivery of the intended volume of therapeutic substance from reservoir 22, plunger-sensor engagement interface 28 causes the position sensor 30 to change state from S3 back to S1. Control circuitry 32 identifies that therapeutic substance delivery apparatus 20 is in a delivery-complete state in response to the position sensor changing state from S3 to S1. This corresponds to line 10 of the state table of
In the above example in which (a) reservoir 22 was filled with a volume of therapeutic substance that is larger than the intended volume and (b) control circuitry 32 compensates for the difference by terminating the delivery upon the intended volume of therapeutic substance having been delivered to the subject, control circuitry 32 terminates the delivery of the therapeutic substance to the subject notwithstanding position sensor 30 remaining in state S3.
Reference is now made specifically to lines 7 of the state table of
Reference is now made specifically to line 9 of the state table of
Applications of the invention described herein can take the form of a computer program product accessible from a computer-usable or computer-readable medium (e.g., a non-transitory computer-readable medium) providing program code for use by or in connection with a computer or any instruction execution system, such as control circuitry 32. For the purpose of this description, a computer-usable or computer readable medium can be any apparatus that can comprise, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Typically, the computer-usable or computer readable medium is a non-transitory computer-usable or computer readable medium.
Examples of a computer-readable medium include a semiconductor or solid-state memory, magnetic tape, a removable computer diskette, a random-access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD. For some applications, cloud storage, and/or storage in a remote server is used.
A data processing system suitable for storing and/or executing program code will include at least one processor (e.g., control circuitry 32) coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution. The system can read the inventive instructions on the program storage devices and follow these instructions to execute the methodology of the embodiments of the invention.
Network adapters may be coupled to the processor to enable the processor to become coupled to other processors or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.
Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object-oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the C programming language or similar programming languages.
It will be understood that the methods described herein can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer (e.g., control circuitry 32) or other programmable data processing apparatus, create means for implementing the functions/acts specified in the methods described in the present application. These computer program instructions may also be stored in a computer-readable medium (e.g., a non-transitory computer-readable medium) that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the methods described in the present application. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the methods described in the present application.
Control circuitry 32 is typically a hardware device programmed with computer program instructions to produce a special purpose computer. For example, when programmed to perform the methods described herein, the computer processor typically acts as a special purpose computer processor. Typically, the operations described herein that are performed by computer processors transform the physical state of a memory, which is a real physical article, to have a different magnetic polarity, electrical charge, or the like depending on the technology of the memory that is used.
It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description.
The present application claims the priority of U.S. 63/187,939 to Ben-David et al., filed May 13, 2021, entitled, “Reservoir state monitoring,” which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63187939 | May 2021 | US |
