DRUG DELIVERY APPARATUS AND METHOD

Abstract

The invention provides medical device for insertion into a body cavity such as the urinary bladder, and for the release of substances into the cavity. The device includes a core and an expandable balloon surrounding the core. The balloon wall is made from an elastic permeable material. When the balloon is empty, the balloon wall is stretched and applied to a surface of the core. A valve allows introductions of one or more fluids between the wall of the balloon and the surface of the core. The invention also provides a system including the device of the invention and one or more instruments for inserting the device into the body cavity or retrieving the device from the body cavity.

Claims

1. A medical device for insertion into a body cavity comprising: (a) a core; (b) an expandable balloon surrounding the core, the balloon having a wall made from an elastic permeable material, the balloon having an empty configuration and an inflated configuration, the balloon wall being capable of being stretched and applied to a surface of the core when in the empty configuration, and the balloon having a lumen when in the inflated configuration; and, (c) a valve configured to allow introduction of one or more fluids between the wall of the balloon and the surface of the core.

2. The device according to claim 1 wherein the core is made from a rigid or semi-rigid material.

3. The device according to claim 1 wherein the wall of the balloon forms a fluid impervious seal with the core.

4. The device according to claim 1 further comprising one or more magnetic elements.

5. The device of claim 4 wherein the magnetic elements are embedded in the wall of the balloon.

6. The device according to claim 1 wherein the balloon further comprises one or more additional lumens.

7. The device according to claim 1 adapted for insertion into a urinary bladder.

8. The device according to claim 2 wherein the core is hollow.

9. A system comprising: (a) an implantable medical device comprising: a core; an expandable balloon surrounding the core, the balloon having a wall made from an elastic permeable material, the balloon having an empty configuration and an inflated configuration, the balloon wall being stretched in the empty configuration and applied to a surface of the core, and the balloon having a lumen in the inflated configuration; and a valve configured to allow introduction of one or more fluids between the wall of the balloon and the surface of the core. (b) one or more instruments selected from an insertion instrument for inserting the device into the body cavity and a retrieval instrument for retrieving the device from the body cavity.

10. A method for treating a body cavity comprising: (a) providing an implantable medical device comprising: a core; an expandable balloon surrounding the core, the balloon having a wall made from an elastic permeable material, the balloon having an empty configuration and an inflated configuration, the balloon wall being stretched in the empty configuration and applied to a surface of the core, and the balloon having a lumen in the inflated configuration; and a valve configured to allow introduction of one or more fluids between the wall of the balloon and surface of the core; (b) inserting the device into the body cavity; and, (c) inflating the balloon with at least one solution or suspension by injection the solution or suspension through the valve between the surface of the core and the wall of the balloon.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Some embodiments of the present invention are herein described, by way of example only, with reference to the accompanying drawings. With specific reference to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the invention.

[0051] Attention is now directed to the drawings, where like reference numerals or characters indicate corresponding or like components. In the drawings:

[0052] FIG. 1A shows a cross-sectional view of a device for treating a body cavity having a balloon formed from an elastic material, the balloon being in an empty state, in accordance with embodiments of the present invention;

[0053] FIG. 1B shows a cross-sectional view of the device of FIG. 1A with the balloon in an inflated state;

[0054] FIG. 1C shows a cross-sectional view of a device for treating a body cavity having a balloon with the balloon having a dimpled surface in the inflated state;

[0055] FIG. 2 shows a cross-sectional view of the device of FIG. 1 inflated with oil based solution or suspension and an aqueous based solution or suspension;

[0056] FIG. 3 A shows a cross-sectional view of a balloon-shaped device with a hollow core in accordance with embodiments of the present invention;

[0057] FIG. 3B shows a cross-sectional view of the device of FIG. 3A including ferromagnetic particles in the wall of the balloon, in accordance with embodiments of the present invention;

[0058] FIG. 3C shows a cross-sectional view of the device of FIG. 3A including ferromagnetic particles in the lumen of the device, in accordance with embodiments of the present invention;

[0059] FIG. 4A is a cross-sectional view of device having two balloons, one inside the other, in a non-inflated state, in accordance with embodiments of the present invention; and

[0060] FIG. 4B shows the device of FIG. 4A after inflating the two balloons.

DESCRIPTION OF THE INVENTION

[0061] In one of its aspects, the present invention provides a device for delivery into a body cavity, such as the urinary bladder, of such compounds as drugs, therapeutic agents, neutriceuticals, collectively referred to herein as drugs

[0062] The device includes an inflatable balloon that serves as a reservoir for a solution or suspension containing a drug for controlled sustained release. The wall of the balloon is made from an elastic permeable material that allows diffusion of molecules through the wall of the balloon.

[0063] The device may include a balloon-in-balloon configuration where the balloons can be inflatable alone or in combination. In this case, the wall of the outer balloon is made from an elastic material that allows diffusion of molecules through the wall of the outer balloon and serves as a reservoir for holding a drug for controlled sustained release, by diffusing through the walls of the outer balloon. The inner balloon is designed to be inflated with a substance to impart to the system a desired specific gravity. Thus, for example, the inner balloon may be filled with air, gas or oil for buoyancy of the system in urine.

[0064] After inflating the balloon with a solution or suspension containing the substances and inserting the device into the body cavity, the substances are released by diffusion through the wall of the system into the cavity.

[0065] The device is inserted into the body cavity and may be subsequently removed from the body cavity. In the case of the urinary bladder, the device can be inserted and removed from the bladder, via the urethra, in both males and females. The device is preferably delivered into the body cavity in an empty state. After delivery of the device to the body cavity, the balloon is inflated with a solution or suspension containing the substance or substances to be released into the urine. The substances to be released may be dissolved or suspended, for example, in water or oil. Oils that can be used include, for example, silicon oils, vegetable oils or mineral oils such as Superla Light mineral oil from Chevron Corp. The inflated balloon may be left in the body cavity for long periods of time. The device can be removed when the treatment cycle is completed or the drug reservoir/s is depleted, and if necessary, replaced with a new device. The balloon can be inflated with numerous drugs to be delivered to the cavity separately or in combination, for example, in effective amounts, for the treatment of various disorders, such as interstitial cystitis, overactive bladder/urge incontinence, superficial bladder tumors and chronic bladder infections.

[0066] The device of the invention may be deployed in the body cavity in a single insertion. After its insertion, by loading sustained and other controlled release drug solutions, the balloon can remain in the cavity for long time periods, making it suitable for long term treatments, instead of, for example, the contemporary trans-urethral instillations necessitating repeated catheterizations, which heighten the risks of urethral injuries and urinary tract infections.

[0067] FIGS. 1A, and 1B show a device 20, for drug delivery in accordance with one embodiment of the present invention. The device 20 is shown in FIG. 1A in its empty configuration of the device and in FIG. 1b in an inflated configuration.

[0068] The device 20 includes an inner core 22 formed from a rigid material and an elastic skin or wall 24 to be inflated to form a balloon. The wall 24 attaches to the core 22, around the edges 27 of the core 22, the attachment being such that a fluid impervious seal, against fluids, such as air, liquid, oil, and the like, is formed. The balloon 24 is made from an elastic material that allows diffusion though the wall of the balloon of the substances to be released. One suitable material for the wall 24 is a type of silicone material known commercially as ELASTOSIL LR 3003 from Wacker Chemie AG. This material is also punctureable by standard medical needles, such that the devices 20 can be deflated, directly though the lumen 28 if necessary, as detailed below. The thickness and permeability of the balloon wall 24 can be modified during its production process. Even in the empty configuration (FIG. 1a), the material of the wall of the balloon is somewhat stretched so that the ball of the balloon is tightly applied to the surface of the inner core 22.

[0069] The core 22 contains a magnetic material 23 and a valve 26. The valve 26 is designed for piercing by a needle or a needle-like tip at the end of an inserting device, in order to introduce into the balloon of the device 20a solution or suspension. The valve 26 may be a self-sealing valve, any one-way valve, such as a duckbill valve or a ball valve. The magnetic material 23 includes a slot 23x through which the solution or suspension passes before entering between the wall 24 of the balloon and the surface of the core 22 to inflate and form the balloon 8. The solution or suspension enters between the wall of the balloon 24 and the core 22 causing the material of the wall of the balloon to expand until the balloon acquires its desired configuration (FIG. 1B).

[0070] Since the wall of the balloon 24 is initially stretched in the empty configuration of the device, the wall of the balloon will be stretched regardless of the amount of fluid introduced into the balloon. Thus, a given device may be used to contain a selectable amount of fluid over a range of volumes. The elasticity of the wall of the balloon allows the balloon to spontaneously contract as fluid leaves the lumen 28 of the balloon.

[0071] The device can expand to, a spherical shape (as shown in FIG. 1B) or a substantially spherical shape. FIG. 1C shows a device 20 of the invention in which the inflated balloon has a dimpled surface, in order to increase the surface area of the balloon and enhance the rate of release of the drugs.

[0072] As stated above, the balloon wall 24 is made from an elastic material that allows drugs to permeate or diffuse through the wall 24. In the case of the urinary bladder, drugs diffusing though the wall 24 are released into the urine and contact the urothelium of the bladder, so that the drug is locally administered.

[0073] The shape of the expanded balloon can be spherical (FIG. 1b), ovoid, flattened or multifaceted. The inner cavity or lumen 28 of the balloon can be divided into two or more cavities or lumens. The balloon can also be formed of separate 28, 28 lumens, or otherwise segregated lumens, as shown, for example, by the balloon devices 220, 220 of FIGS. 4A and 4B, respectively.

[0074] The balloon can be filled with oil and one or more oil soluble drugs. The oil provides buoyancy as well as a drug carrying matrix. Alternately, the balloon can be inflated with a combination of oil and water/saline, the water/saline containing one or more water soluble drugs. The oil part is for buoyancy but can also contain oil soluble drugs. The proportions of oil and water depend on the weight of the balloon, enough to give the balloon sufficient buoyancy in urine.

[0075] The balloon may have a positive buoyancy for allowing floating (its weight less than the buoyant force) or a neutral buoyancy for allowing hovering (its weight equal to the buoyant force). In the case of the urinary bladder, buoyancy of the balloon devices 2 reduces contact between the balloon and the trigone region of the bladder which is rich in sensory nerve ends and is situated near the base of the bladder. Should the balloon device have negative buoyancy, it will sink to the bottom of the bladder, contacting the trigone region possibly causing irritation and pain.

[0076] The device is such that during normal use, it may contact the bladder inner surface. At the end of urination, a part of the device may contact the trigone region. Buoyancy of the device allows the device to float on the urine as urine accumulates in the bladder, reducing further irritation.

[0077] Attention is now directed to FIGS. 2A and 2B, which show balloon devices 20, 20 with filled lumens 28, for example, with one or more drug solutions, buoyancy agents, gases and the like. The filling has expanded the balloon device 20, and along with balloon

[0078] Attention is now directed to FIG. 2, which shows the device 20 after being inflated with a combination of an aqueous solution or suspension of one or more drugs and an oil-based solution or suspension of one or more drugs. The aqueous solution 54 separates from the oil based solution 52 in the lumen 28. Two different drugs may be delivered from the balloon device 20, one from the water based solution 54 and one from the oil based solution 52, with the oil based solution also providing buoyancy to the device 20. In other embodiments, gases, such as air, can be also be inserted into the lumen 28. These gases provide buoyancy to the device 20.

[0079] FIG. 3A shows an alternative balloon device 120, in accordance with another embodiment of the invention comprising central hollow cylindrical core 123 made from a rigid or semi-rigid material that may be a permeable material. The core 123 surrounds a channel 121 passing through the device 120, and a valve 126, similar to valve 26 detailed above for the device 20 that is positioned in the wall of the core 123. All other components of the balloon device 120 are the same or similar to those for the balloon device 20, as described above, and accordingly, have the same reference numerals increased by 100. The device 120 may not contain a magnetic element, in which case it can be removed from the bladder using endoscopic grasping forceps. Alternatively, the magnetic elements for the device 120 may be, for example, incorporated or embedded in the wall 124 of the balloon 120 as ferromagnetic particles 140 or strips, as shown in FIG. 3B. These particles 140 are typically added (impregnated/embedded into the wall 124) during balloon production. As another alternative, ferromagnetic particles 142 can be injected into the lumen 128 (dry or in solution), for example, as shown in FIG. 3C.

[0080] FIGS. 4A and 4B show a balloon device 220 in accordance with another embodiment of the invention. The balloon device is formed of an outer balloon 220x whose interior includes a separate balloon 320, within the lumen 228 of the outer balloon 220x. In the device 22, components which are the same or similar to those for the device 20, as described above, and as shown, and accordingly, have the same element numbers increased by 200, for the outer balloon 220x, and increased by 300 for the inner balloon 320. The device 220 has a core 222.

[0081] The device 220 is shown in FIG. 4A with B with both balloons 220x and 320 in non-inflated states in an empty configuration, and in FIG. 4B in an inflated configuration. The walls of the two balloons are made from an elastic material that is somewhat stretched prior to filling of the balloons, so that the balloons are tightly applied to the surface of the core 222 in the empty or non-inflated state (FIG. 4A).

[0082] After inflation (FIG. 4B), an inner lumen 328 is separate from the outer lumen 228. The core 222 includes two valves 226a, 226b (e.g., self-sealing valves similar to valves 26 detailed above) at the ends of the core 222. The first valve 226a is at an end 222a of the core 222. The core 222 includes openings 227a into the inner lumen 328 of the inner balloon, as accessed through the valve 226a. Materials (substances), such as liquids, oil, water, and gases, are injected into the lumen 328 (via the openings 227a of the tube 227) through the valve 226a to expand it. Through a second valve 226b and an opening 223z in the core 222, materials, such as liquids, such as oil and water, and gases, such as air, are injected into the lumen 228 of the balloon 220x to expand it. The core 222 may include magnetic elements 223, as explained above with reference to the device 20 shown in FIG. 1. For example, the dual lumens 228, 328, may be such that one lumen 228 serves as a reservoir for a water based solution with drugs, and the lumen 328 serves as a reservoir for the oil based solution, without drugs, the oil-based solution providing buoyancy to the balloon device 220. However, the components of the lumens 228, 328 may be switched, if desired. Gases, such as air, may also be added in the amounts desired, into one or both lumens 228, 328, for buoyancy of the balloons 220, 220.

[0083] For example, both balloons 220x, 320 can be inflated separately by using the same needle inserted first through the first valve 226a for filling the inner lumen 328, and then moving through the second valve, to inflate the outer lumen 228. For example, the needle, through which the material is inserted into each lumen 228, 328, can be the same, but the syringe attached to the needle is changed to inject different materials to each separate lumen 328, 228.

[0084] The device of the invention can be inserted into the bladder and removed from the bladder, for example by the instrument disclosed in US Patent Application Publication No. US 2010/0016834 A1, the disclosure of which is incorporated by reference herein. These instruments are advantageous as they do not require any endoscopic manipulation in their operation. Collapse of the balloon 24 will be necessary for removal of the balloon. For this purpose the balloon wall 24 may be punctured with a retrieval instrument, and the residual fluid in the balloon emptied prior to removal of the balloon from the bladder.

[0085] Additionally, intravesical drug delivery can be improved by prolonging the total drug exposure and by enhancing the delivery of agents to bladder tissues by enhancing bladder mucosa permeability by intravesical hyperthermia. Also, the addition of a permeability enhancing chemical such as dimethyl sulfoxide (DMSO) into the drug carrying matrix may promote the penetration of water-soluble or lipophilic drugs.

[0086] The device may include an externally commanded heating element for increasing the urine temperature to 40-45 C. for increasing the urothelial permeability to the drugs.

[0087] The device may include a pressure sensor for detecting bladder pressures. When the bladder pressure reaches a predetermined threshold, a command or signal may be given to the heating element to start heating, to increase the urine temperature, as detailed above for increasing the urothelial permeability.

[0088] While the balloon has been shown and described above for use in the bladder, the balloon 20 can be used for other intracavitary or regional treatments such as intra-gastric, intra-peritoneal and intra-thecal applications, without or with slight modifications.

Example 1

[0089] Experiments were performed using Lidocaine dissolved in oily substances using two different expansion volumes (one with 10 ml, the other with 16 ml) of the balloon of the device 20. The results showed that a hydrophobic/lipophilic drug, Lidocaine, dissolved in oily substances was released in large quantities through the silicone balloon wall.

[0090] A. The balloon was expanded by injection of 10 ml of the oily solution into the balloon. A series of 4 experiments using lidocaine dissolved in oil was performed. The results were as follows: [0091] 1. After 28 days436 mg out of 500 mg was released. [0092] 2. After 29 daysall the 500 mg was released (out of 500 mg). [0093] 3. After 22 daysall the 500 mg was released (out of 500 mg). [0094] 4. After 63 daysall the 1000 mg was released (out of 1000 mg).

[0095] B. The balloon was expanded by injection of 16 ml of the oily solution into the balloon. 2 groups and a series of 3 experiments using lidocaine dissolved in oil were performed. The results were as follows: [0096] 1. After 21 days: all the 500 mg was released (out of 500 mg) [0097] 804 g was released, out of 1000 mg [0098] 1086 mg was released, out of 1500 g [0099] 2. After 84 daysall the 500 mg was released (out of 500 mg) [0100] all the 1000 mg was released (out of 1000 mg) [0101] all the 1500 mg was released (out of 1500 mg)

[0102] The present invention, while shown for human use, is also suitable for animal use. Additionally, while the balloons are shown and described for use in the bladder, this is exemplary, as the balloons and their methods of use, as per the invention, may be used in all areas of the human or animal body.

[0103] The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

[0104] The terms comprises, comprising, includes, including, having and their conjugates mean including but not limited to.

[0105] As used herein, the singular form a, an and the include plural references unless the context clearly dictates otherwise. For example, the term a compound or at least one compound may include a plurality of compounds, including mixtures thereof.

[0106] The word optionally is used herein to mean is provided in some embodiments and not provided in other embodiments. Any particular embodiment of the invention may include a plurality of optional features unless such features conflict.

[0107] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

[0108] Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.