WO2009063375A1

WO2009063375A1 - Ingestible electronic capsule

Info

Publication number: WO2009063375A1
Application number: PCT/IB2008/054672
Authority: WO
Inventors: Hans Zou
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2007-11-13
Filing date: 2008-11-07
Publication date: 2009-05-22

Abstract

An ingestible capsule (100, 500) comprising at least one reservoir (104), dispensing means (966) to dispense medicament from the reservoir to an outlet under the control of a processor (906), and at least one expandable member (1604, 150) wherein the processor (906) is programmed to expand the at least one expandable member responsive to a signal issued by a sensor (905) after detecting a condition typical for the stomach environment. The medicament can, e.g., be coated with a gastroresistant enteric coating material.

Description

Ingestible electronic capsule

FIELD OF THE INVENTION

The present invention relates to an electronically controlled ingestible capsule for release of a medicament, e.g. for medical or veterinary treatment.

BACKGROUND OF THE INVENTION

Electronically controlled ingestible capsules can be used to provide therapeutic treatment during traversal of the gastrointestinal alimentary tract. The capsule can be provided with an electronically controlled medicament delivery system. The capsule is moved by the peristaltic movement of the muscles along the gastrointestinal tract. An electronically controlled capsule can be programmed or controlled to deliver or dispense a medicament according to a dispensing timing pattern while traversing through the gastrointestinal tract. The electronically controlled capsule can include control and timing circuitry for controlling the opening and closing of a valve or hatch according to the desired dispensing timing pattern for dispensing a medicament stored within a medicament reservoir of the capsule.

The dispensing timing pattern can be preset and it can be fixed not being susceptible to a person's physiological processes and conditions, mood, age, gender, ailments, earlier-administered medicaments, etc. The electronically controlled capsule allows a person to take all capsules substantially simultaneously, e.g. with breakfast, so that no more capsules are required for the day. Medication that does not fit into one electronically controlled capsule can be coordinated with other electronically controlled capsules for the full day's payload regimen. All of the medicaments required to be taken during a particular time period, for example, during a 24-hour period, can be provided within one or more electronically controlled capsules which can all be taken at the same time. The electronically controlled capsules can have different dispensing timing patterns, so that a full day's coverage can be obtained. Further, at a preset moment in time during the dispensing timing patterns, the electronically controlled capsules present in the body may be programmed to stop dispensing medicament in the expectation that a new set of capsules will be taken. This prevents accidental overdose by having only the most recently taken capsules dispensing medicament in the body.

A program controlled medicament delivery system using such capsules avoids the need for a caregiver to wake up or otherwise disturb a patient or resident for the sole purpose of administering a medicament or to track down a patient or resident who may be in a different part of the hospital or nursing home for the sole purpose of administering a medicament. It also reduces the overload required for inventorying, ordering, tracking and logging the medicaments.

As used herein, the word "medicament" refers to medicines, placebos, non- medicinal substances, contrast agents, gases, fluids, liquids, radiological agents, imaging or medical markers, sensors for monitoring the person's vitals, etc.

There are significant numbers of medicaments which can be absorbed by the body only in the proximal small intestine. It is therefore desirable to have those medicaments available in the upper gastrointestinal tract for a long period. The natural transit time in the entire small intestine (from the stomach to colon) is more or less constant, only up to about 4 hours and varies a lot depending on food intake of a patient. However, to keep a steady concentration of medicament in a patients body and to minimize the number of medicament administrations, it is desirable to have the medicament available in the treated part of the gastrointestinal tract for a longer period, e.g., for 10 hours or more. To this end, it has been proposed in WO 2006077529 to use a capsule comprising a balloon which is selectively inflatable and deflatable.

The object of the invention is to provide a treatment system with controllable availability of a medicament in the gastrointestinal tract.

BRIEF DESCRIPTION OF THE INVENTION

The object of the invention is achieved with an ingestible capsule comprising at least one expandable member and a processor programmed to expand the at least one expandable member responsive to a signal issued by a sensor after detecting a condition typical for the stomach environment. Although the stomach as such does not absorb the medicament, it has been found that the availability and absorption of the therapeutic substance in the proximal small intestine can substantially be improved by increasing the retention time of the capsule in the stomach. To this end, a capsule can be used comprising at least one expandable member which is expanded after entry into the stomach to a size preventing passage through the pylorus and which is re-contracted to a size allowing passage through the pylorus after release of an amount of one or more medicaments over a pre-determined period of time in accordance with a pre-set dispensing timing pattern. Such a capsule can, e.g., be an electronic pill comprising a processor which is programmed to expand one or more expandable members responsive to a signal issued by the sensor after detecting a condition typical for the stomach environment. The processor can also be programmed to re-tract or deflate the one or more expandable members after release of a pre-determined amount of medicine and/or after a pre-set time period.

The expandable member can for example be a member which is selectively inflatable and deflatable, such as is described in WO 2006077529, and / or selectively unfoldable and re-foldable. Alternatively or additionally, one or more of the expandable members can be dissolved and / or decoupled or disengaged, e.g. after a pre-set time period. The capsule can contain particles of a medicament coated with a gastroresistant enteric coating. Such coatings are resistant to the acidic stomach environment but soluble in the less acidic intestinal environment of the intestine, enabling controlled release of the therapeutic substance in the intestine. The enteric coatings can for example be based on poly(meth)acrylates. Suitable examples of commercially available enteric coatings are for instance the Eudragit® coating materials of Degussa, and the Kollicoat® coating materials of BASF.

The medicament can be a solid particulate material or liquid droplets or even be gaseous material enveloped by an enteric coating material. The medicament can also be a mixture of materials, for instance precursors or components of a medicine which form the medicine when the components mix after dissolving of the enteric coating in the small intestines.

The capsule can comprise timing circuitry. Upon receiving an electrical signal, e.g. from the sensor detecting a condition typical for the stomach environment, the timing circuitry begins to clock the dispensing time period and control a release controller by transmitting a signal thereto. The timing circuitry can include a microprocessor programmed with the preset dispensing timing pattern for relaying the signal to the release controller, such that the medicament is dispensed during the dispensing time period according to the preset dispensing timing pattern. The voltage level of the signal can relay the size of the valve opening for controlling the quantity of the medicament dispensed at each moment of the dispensing time period substantially according to the preset dispensing timing pattern. Alternatively, the signal transmitted by the timing circuitry to the release controller only relays the opening and closing of the valve and not the size of the valve opening.

The release controller can be a micro-electromechanical mechanism capable of receiving the signal from the timing circuitry and generating a signal having a variable voltage level to the electronically controlled valve for closing the valve 106 and controlling the size of the valve opening or degree of opening of the valve (in accordance with the voltage level of the received signal). In the simplest case, the release controller is a transistor or D/ A circuit that provides voltages to the valve causing it to open or close. The dispensing means can for instance comprise one or more valves or hatches. The electronically controlled valve is preferably a micro-electromechanical mechanism capable of being electrically controlled by a signal having a variable voltage levels. Each voltage level corresponds to a different size opening for the valve opening and one voltage level (or no voltage at all, i.e., no signal) corresponds to the valve being closed. The valve can be similar in operation to valves used in ink-jet printers for dispensing ink in accordance with the amount that the valve is opened. The valve can be a microfluidic valve for controlling the movement of minute amount of liquids or gases in a miniaturized system. In an alternate embodiment, the reservoir can be construed as a micro-syringe, whereby pressure applied to a plunger of the syringe dispenses medicament via a needle tip of the micro-syringe which is in fluid communication with an opening in the capsule shell. In this embodiment, the opening replaces the valve. It is contemplated, however, that a check valve is placed at the needle tip of the micro-syringe to avoid leakage of the medicament during time periods within the dispensing time period where there should be no dispensing according to the preset dispensing timing pattern, and/or for controlling the quantity of medicament dispensed during the dispensing time period.

Optionally, the capsule comprises a pliant membrane enveloping the one or more expandable members. Such membrane substantially reduces friction with surrounding tissue. Such membrane can for instance be made of a cloth or stretchable foil, stretchable under the action of the unfolded members. Suitable materials for such a membrane are for example high-pressure, non-elastic plastics, which are formed of materials such as flexible polyvinyl chloride (PVC), cross linked polyethylene (PE), polyester polyethylene terephthalate (PDT), polyamide, or polyurethane; or the low-pressure elastomeric variety, which are formed of materials such as latex or silicone. Optionally, the pliant membrane can be fixed to at least one of the one or more unfoldable members, e.g., by a glue. Alternatively, it can be fixed to any other part of the capsule or be loose. In a further alternative, the pliant membrane can be part of one or more of the unfoldable members. The pliant membrane can be permeable for medicament to be released by the capsule. Alternatively, the membrane can have an opening in line with a medicament dispensing opening or nozzle. In case the capsule is used for diagnostic purposes, the membrane may be provided with openings allowing a sensor in the capsule to interact with the environment to be examined. Coatings may be provided on the membrane, such as lubricious coatings, hydrophilic or hydrophobic coatings, abrasion and puncture resistant coatings, tacky or high friction coatings, conductive coatings, anti-thrombogenic coatings, drug release coatings, reflective coatings and/or selective coatings.

In a specific embodiment, at least one of the one or more unfoldable members can be a fin which is pivotable between the folded position, when it is at least partly sunk in the outer surface of the capsule, and the unfolded position. The fins can, e.g., be made of a flexible material such as for instance biocompatible materials used to fabricate implantable medical devices. These materials include Pellethane® 2363 polyether urethane series of materials available from Dow Chemical Company and Elasthane polyether urethane available from the Polymer Technology Group, Inc. Other materials include PurSil® and CarboSil® also available from the Polymer Technology Group, Inc.

The expandable member can for example be a fin having a pivot pin and a slider pin wherein the pivot pin is pivotably mounted in a stationary first ring and the slider pin is slideably engaged in a lot in a second ring which is concentrically rotatable relative to the first ring. The capsule can for instance have three or more of such pivotable fins equidistantly arranged over the perimeter of the capsule.

In an alternative embodiment, at least one of the one or more unfoldable members are formed by a strip of an electro active polymer (EAP), such as an ionic polymer metal composite (IPMC), perfluorinated ion exchange membrane platinum composite (IEMP) or an electro restrictive polymer (EP). Such electro active polymer fins can be bended to different positions under an electric voltage applied by the control circuitry.

Optionally, the capsule can be controlled by an external control system, e.g. radio graphical remote control, or the pill can comprise a processor programmed to release medicine from the reservoir via the medicine dispenser upon activation by the sensor. The capsule can also have one or more power sources, such as a battery, which provides power to control circuitry and/or other components of the capsule. An exemplary battery is a thin film lithium battery (e.g., available from Frontedge Technologies TM, located in Baldwin Park, California, US), having a small footprint and a suitable shelf life (e.g., 1% discharge/year). The battery may further be selected from other known batteries, such as photo lithium, silver oxide, lithium coin cells, zinc air cells, alkaline, etc.. Alternatively or additionally the capsule may use passive power. It is contemplated that the power source includes a device configured for scavenging power from another device, which may employ electrostatic, micro fuel cells, micro-heat, temperature gradient, etc. The capsule can comprise a sensor, e.g., on the capsule housing or enclosed within the capsule, where a controllable closure member provides exposure of the sensor 102 to the environment of the capsule. Accordingly, the sensors may be permanently exposed to the environment of the capsule, or may be controllably exposed. The sensors generate sensing signals corresponding to the sensing. The sensing signals can, e.g., be sent to control circuitry and/or remote processing circuitry. Operation of the sensors can be controllably enabled, such as for avoiding generating or processing data that is not of interest, or just sampling data of interest, for conserving resources, such as processing and/or input/output (I/O) resources.

The sensing signals and sensor enablement data describing control of operation of the sensors may be stored by the capsule and retrieved from the capsule once expelled from the patient and/or transmitted to a remote processing circuitry for analysis.

In one embodiment at least one of the one or more sensors pH sensor for sensing pH levels, for example as the capsule is moved along the alimentary tract, and one of the software modules is a pH control software module. The pH control software module monitors sensing signals output by the pH sensor for determining when the capsule has reached a location in the stomach, upon which a control signal is transmitted for controlling a function of the capsule. The control signal may be provided, for example, to a medicament dispensing system for dispensing the medicament or a portion thereof. Optionally, the pH control software module may continue to monitor the pH levels and dispense the medicament in response to the pH levels for delivery of the medicament at a desired rate.

The pH readings by the sensor can trigger dispensing of the medicament. The pH level of the stomach is typically about 2.0, ranging from 1-3 in normal healthy humans. Processing of control signals for controlling dispensing of the medicament may be performed by control circuitry or a remote processor. The processing of the control signals may include consulting a mapping (e.g., a look up table, a continuous mapping, a searchable database, etc.) of positions along the alimentary tract versus pH levels (or ranges thereof), and using the mapping to determine the location of the capsule in accordance with the current pH level.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be elucidated with reference to the Figures wherein:

Figure IA shows an embodiment of the capsule according to the present invention;

Figure IB shows an enlarged schematic diagram of a pressurizing valve, depressurizing valve and exhaust channel area of one balloon of the capsule of Figure IA;

Figure 2A shows an alternative embodiment of a capsule according to the invention;

Figure 2B shows the capsule of Figure 2 A with unfolded fins without the pliant membrane; Figure 2C shows the capsule of Figure 2 A with unfolded fins;

Figure 2D shows the capsule of Figure 2A in longitudinal cross section with unfolded fins.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION Figure IA shows an ingestible capsule 100 provided with a braking system

1601 including at least one gas pressurization module 1602 and at least one balloon 1604, where inflation of the at least one balloon 1604 during traversal of the stomach controls slows or stops movement of the capsule 100 in the stomach.

Additionally, inflation by a selectable amount of selected balloon(s) 1604 of the at least one balloon 1604 may assist in steering and/or positioning the capsule 100, such as for orienting the capsule 100 in a desired orientation. The capsule 100 is a free standing capsule which is not attached structurally to a device located external to the patient.

Inflation and deflation of the balloon(s) 1604 is controlled by control circuitry or microprocessor 906. When inflated, the balloon(s) 1604 create drag, and/or apply pressure or generate friction with respect to the stomach wall.

In Figure 1, balloon 1604 A is shown in an inflated state, and balloon 1604B is shown in a deflated state. Figure IB shows region 1700 in greater detail, in which a pressurizing closure member 1606 is shown, which is provided between the gas pressurization module 1602 and an associated balloon 1604 for selectively allowing a one- directional flow of gas from the gas pressurization module 1602 to the balloon 1604. Depressurizing closure member 1608 is further provided for selectively allowing a one- directional flow of gas from an associated balloon 1604 through an associated exhaust channel 1610 for allowing deflation of the balloon 1604 by allowing gas to exit the balloon 1604 through the exhaust channel 1610 and into the ambient environment of the capsule 100.

Operationally, the balloon(s) 1604 are inflated or deflated when the capsule arrives in the stomach, e.g., in accordance with a sensed property or instructions from a remote processing device or another capsule. After delivery of medicament particles coated with an enteric coating, the balloon(s) 1604 may be fully or partially deflated for allowing the capsule 100 to continue traversing the alimentary tract, after which the balloon(s) may selectively re-inflated, such as for repeating the procedure at a different location along the alimentary tract.

In the aggressive stomach environment, with a pH of about 2, the medicament particles are protected by the enteric coating. The medicament particles leave the stomach via the pylorus to arrive at the small intestines, where the enteric coating is solved and the medicament is released and absorbed by the intestines. During the retention time of the inflated capsule in the stomach, the medicament can be released in a controllable way during a prolonged time. This way the availability of the medicament in the small intestines is effectively improved. The respective balloon(s) 1604 may be mounted on the capsule 100. Figure IB shows an exemplary flange 1612 formed on housing 102 to which balloon 1604 is secured for mounting. The elasticity of the balloon 1604 causes the balloon 1604 to squeeze the neck of balloon 1614 with a force against the flange 1612 for maintaining the balloon 1604 secured. Additional structural features for securing the neck 1614 to the flange 1612 may be provided with the neck 1614 or flange 1612, such as ridges, ribs, mating grooves or notches, etc. The respective balloon(s) 1604 may be secured to the capsule 100 in a variety of ways. For example, a respective balloon 1604 may include an elastic strap or pouch attached to the balloon 1604 or integral therewith which grasps the housing 102 in addition to or instead of flange 1612. The tension due to elasticity of the strap/pouch holds the balloon 1604 in position. The housing, the neck of the balloon 1614 or the strap/pouch could be provided with additional securing mechanisms, such as ribs, mating grooves or notches, etc. The strap/pouch may be configured to accommodate other features of the capsule 100, such as having apertures, e.g., for dispensing of medicament. Methods and structures known in the art, such as a balloon catheter combination may further be mounted to capsule 100, e.g., the catheter is mounted to the capsule and the balloon 1604 is mounted to the catheter. The catheter may extend only slightly from the housing 102.

The capsule 100 comprises a medicament dispensing system 901 including at least one reservoir 104 for holding a medicament, a push or pressure mechanism for exerting a force on the reservoir and/or the medicament for displacing medicament stored in the reservoir 104, and a closure member 966, such as a MEMS micro valve or as is enabled by microfluidic systems of inkjet printers and the like. The reservoir(s) is in communication with at least one aperture in the housing 102 through which the medicament can exit the capsule 100. The medicament delivery system 901 is controllable by the control circuitry

906, such as by controlling the respective pressure mechanisms and/or the at least one closure member 966. Control of the medicament control system 901 may include controlling the timing of delivery of the medicament, the amount of medicament delivered, the rate of delivery of the medicament and/or the force at which the medicament is delivered. The medicament delivery system 901 can for example be controllable for facilitating controlled intermittent delivery of the medicament.

The closure member 966 can be controllably opened or closed, wherein when open, the closure member 966 preferably allows fluid to flow in only one direction. In one embodiment, the closure member 966 includes a MEMS valve including a micro valve, such as a fluidic transistor, and an associated micro valve actuator mechanism.

The micro valve is preferably in a normally closed state (e.g., the micro valve substantially does not allow flow through the micro valve in either direction) and is actuatable to an open state (e.g., the micro valve allows flow of medicament for exiting the reservoir 960 and/or the capsule 900) by the actuator mechanism for a selected duration of time for allowing the flow of fluid. Preferably the rate at which the medicament flows through the micro valve when in an open state is selectable and controllable. Control of the actuator mechanism and/or the micro valve is provided by the control circuitry 906. Commercially available examples of micro valves include micro valves designed by Redwood Microsystems. An actuator mechanism may include a micro motor which may be powered by a power source for mechanically opening and closing a moveable mechanism within the micro valve. The size of the opening is preferably selectable for controlling the rate at which the medicament flows when in an open state. Alternatively, the actuator mechanism may control displacement of the medicament with respect to an opening in the micro valve. The actuator is preferably controllable for controlling the degree of displacement and thus the rate at which the medicament flows when in an open state.

The micro valve may include structural materials, such as Si, 5iO2, SiN, Ti, and/or TiNi, and gasket materials, such as PDMS, Polymide, Polycoarbonate, Parylene and/or silicone rubber. The actuator mechanism may include, for example, electrostatic, magnetic, piezoelectric, bimetallic, shape memory alloy (SMA), pneumatic and/or thermo pneumatic construction and functions.

Another exemplary closure member 966 includes a valve having at least one controllable artificial muscle made of a polymer that expands or contracts in response to an electrical signal for substantially plugging or unplugging an aperture. Similarly, the expansion and contraction of the artificial muscle may be included in the actuator mechanism for controlling displacement of the medicament for controlling flow thereof.

The capsule 100 further comprises a pH sensor 905. When it detects a pH between 1 - 3, it sends a signal to the processor 906 upon which the processor 906 initiates inflation of the expandable balloons 1604 and subsequently activates the dispensing system 901.

Figures 2 A - 2D show a different capsule 500 according to the present invention. The same reference numbers are used for the same components as used for the embodiment shown in Figures IA-D. For reasons of clarity, Figures 2 A and 2B show the capsule 500 without the pliant membrane envelope. Sunk in the outer shell 102 are a number of strips 150 of an electro active polymer. The strips stretch in the longitudinal direction of the capsule and are equidistantly and coaxially disposed in a circular array. One end of each strip is permanently attached to the outer shell 102. The electro active polymer strips 150 can be bended under an electric voltage to an unfolded position, as shown in Figure 2B. In this position, it stretches the pliant membrane 129 as shown in Figure 2C.

In this specific embodiment, the capsule 500 is a remote controlled capsule with an antenna 502 (see Figure 2D) for receiving control signals, such as RF control signals, for remotely communicating commands or instructions to the capsule 500. The antenna 502 may also transmit information from the capsule 500 to the outside as further described below. In an alternative embodiment the antenna can be provided in a folded configuration. The control signals received by the capsule 500 are transmitted to RF communication circuitry 504 within the timing circuitry 110 via wire leads 506. The RF communication circuitry 504 includes a receiver and processing circuitry for processing and analyzing the received RF control signals and accordingly determining one or more particular actions indicative of the instructions or codes provided by the control signals.

The actions are determined by correlating the instructions or codes with one or more actions using a data structure, such as a look-up table, within the timing circuitry 110. The instructions provided by the control signals can include overriding the preset dispensing timing pattern programmed within the timing circuitry 110 for one or more moments in time during the dispensing time period. This may be necessary to dynamically increase or decrease the amount of medicament being dispensed during a particular time during the dispensing time period due to the person's vitals at a particular moment in time and other factors. The person's vitals can be monitored using conventional systems and sensors. One or more of these sensors can be provided within the capsule 500 itself for sensing the person's vitals as the capsule 500 traverses the gastrointestinal tract and for transmitting the information to the timing circuitry 110 which in turn dynamically adjusts the dosage based on the person's sensed vitals. The instructions provided by the control signals can further change the dispensing timing pattern by reprogramming the timing circuitry 110 with a different dispensing timing pattern. The control signals can further provide instructions as to which moment in time of the new dispensing timing pattern the dispensing of the medicament should commence. The new dispensing timing pattern can be transmitted via the control signals or be stored within a memory of the timing circuitry 110, where the memory includes a plurality of dispensing timing patterns and the control signals indicate which dispensing timing pattern is desired.

The control signals can also instruct the control and timing circuitry 108 to terminate the dispensing of the coated medicament, in case the wrong medicament was administered, the wrong dose was prescribed, the person had an adverse reaction to the medicament, etc. The control signals can further instruct the control and timing circuitry 108 to release a bowel slowing medication, such as Lomotil®, stored within a reservoir or micro- sac for temporarily halting the progress of the capsule 500 through the gastrointestinal tract. The bowel slowing medication can be released in tandem with the medicament stored within the reservoir 104. The bowel slowing medication can also be provided within a separate capsule.

The generation and transmission of the control signals can be synchronized with an external system, such as an MRI system, ultrasound imaging system, etc., for dispensing the medicament in accordance with the person's vitals monitored by the external system, the mode of operation of the external system, etc. The medicament can be an oral contrast agent used to enhance diagnostic images.

The control signals may for instance transmit unique identification information which is used by the timing circuitry 110 to ensure that the received control signals are for the respective capsule 500. This prevents control signals from initiating an action to a capsule 500 other than the intended capsule 500. The identification information can be a unique serial number which is programmed within the timing circuitry 110. If the received serial number does not match the programmed serial number, the timing circuitry 110 does not respond to the received control signals. Accordingly, the timing circuitry 110 does not perform any action, such as the actions described above.

The communication circuitry 504 includes a transmitter for transmitting signals from the capsule 500. The signals are generated by the communication circuitry 504 for providing information to a caregiver or the person. Information that can be provided includes the particular moment in time of the dispensing time period; the cumulative quantity of medicament dispensed from the beginning of the dispensing time period to a particular moment in time of the dispensing time period; the average quantity of medicament dispensed during each moment in time of the dispensing time period (e.g., each second); etc. Additionally, the transmitter can provide a signal for alerting or notifying a caregiver or the person that the capsule 500 has been taken, in case the caregiver or the person do not remember if the capsule 500 was or was not taken. The transmitter can also provide a signal if the capsule 500 after diagnostic tests are executed by the control and timing circuitry 108 and it is determined that the capsule 500 has malfunctioned, in cases such as if the capsule 500 is not dispensing the medicament, the medicament is not being dispensed according to the preset dispensing timing pattern, etc. The capsule 500 includes an optional RFID tag 508 for tracking, identification, inventory and other purposes using an RFID reading system. The RFID tag 508 can also be used to determine if the capsule 500 was administered by a caregiver or taken by the person, and if so, the RFID tag 508 can be used to determine the general location of the capsule 500 within the gastrointestinal tract.

The capsule 500 further includes a piezo-electric element and associated circuitry 510 for remotely transmitting commands via the communication circuitry 504 to the timing circuitry 110 for remotely controlling the capsule 500. The element 510 is can be affixed to the housing 102 and is capable of being vibrated at one or more predetermined frequencies. The vibration is caused by placing an ultrasound probe, hydrophone or other vibration-causing device in proximity to the person. The frequencies caused by the element 510 are converted to electrical signals by the associated circuitry. The electrical signals are transmitted to the timing circuitry 110 via wire lead 512 where they are processed for determining an action to perform. The action can be one of the actions described above with reference to the control signals provided to the timing circuitry 110 via the wire leads 506. The action is can, e.g., be determined by correlating the vibration of the element 510 to an action using a data structure, such as a lookup table, stored within the control and timing circuitry 108 and accessible by the timing circuitry 110.

The described embodiments of the present invention are intended to be illustrative rather than restrictive, and are not intended to represent every embodiment of the present invention. Various modifications and variations can be made without departing from the spirit or scope of the disclosure as set forth in the following claims both literally and in equivalents recognized in law.

Claims

CLAIMS:

1. An ingestible capsule (100, 500) comprising at least one reservoir (104), dispensing means (966) to dispense medicament from the reservoir to an outlet under the control of a processor (906), and at least one expandable member (1604, 150) wherein the processor (906) is programmed to expand the at least one expandable member responsive to a signal issued by a sensor (905) after detecting a condition typical for the stomach environment.

2. Capsule according to claim 1 wherein the capsule (100, 500) contains particles of a medicament coated with a gastroresistant enteric coating material.

3. Capsule according to claim 1 or 2 wherein at least one of the expandable members is an inflatable member (1604) which can selectively be inflated and deflated.

4. Capsule according to claim 1 or 2 wherein at least one of the expandable members is an unfoldable member (150) which can selectively be unfolded and retracted.

5. Method of administering a therapeutic substance wherein the substance is released from an ingestible capsule (100, 500) comprising at least one expandable member (1604, 150) and a processor (906) programmed to expand the at least one expandable member responsive to a signal issued by a sensor (905) after detecting a condition typical for the stomach environment.

6. Method according to claim 4 wherein the therapeutic substance is at least partly contained in particles coated with a gastroresistant enteric coating.

7. Method according to claim 4 or 5 wherein the expandable member (1604, 150) is selectively moved between an expanded position after arrival of the capsule (100, 500) in the stomach and a contracted position after delivery of at least a part of the medicament.