# US 2019/0167856 A1 · Systems and methods for forming materials in situ within a medical device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0167856 A1 - Document ID: US20190167856A1 - Status: Published application - Kind: A1 - Application number: 16/272,809 - Filed: 2019-02-11 - Published: 2019-06-06 - Earliest claimed: 2013-03-14 - Assignees: Endologix, Inc. - Applicants: Endologix, Inc. - Inventors: Charles Bankert; Paolo Mendoza; Stefan Schreck - Web page: https://patentgrep.com/patent/US20190167856A1 ## CPC - A61L 31/048: {obtained by reactions only involving carbon-to-carbon unsaturated bonds (A61L31/041 takes precedence)} - A61B 17/12113: {within an aneurysm} - A61B 17/12136: {Balloons} - A61L 31/041: {Mixtures of macromolecular compounds} - A61L 31/06: obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds {(A61L31/041 takes precedence)} - A61L 31/14: Materials characterised by their function or physical properties {, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials} - A61L 31/143: {Stabilizers} - A61P 9/00: Drugs for disorders of the cardiovascular system - A61P 9/10: for treating ischaemic or atherosclerotic diseases, e.g. antianginal drugs, coronary vasodilators, drugs for myocardial infarction, retinopathy, cerebrovascula insufficiency, renal arteriosclerosis - A61L 2400/06: Flowable or injectable implant compositions - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS ## Abstract A method for forming a material in an in situ medical device by initiating polymerization of water soluble polymer precursors in an aqueous solution during or after transport of the polymerizable solution from its storage container to a space inside the in situ medical device is described. The stored aqueous solution with water soluble precursors lacks a free radical initiator which, in a powder form, is introduced into the aqueous solution during or after its transport into the space inside the in situ medical device. This storage and delivery system provides greater stability to the stored aqueous solution, allowing it to be stored at ambient temperature and providing extended shelf life over the solutions used in existing in situ polymerization systems. The flexibility to store and deliver/transport only one aqueous solution, instead of requiring the use of two different solutions, is also a benefit. ## Claims ### Claim 1 A system for treatment of an aneurysm in a patient, the system comprising: an expandable member adapted for delivery into and expansion within the patient; a tube in fluid communication with a space inside the expandable member, or directly into the expandable member; and a filter disposed in the tube upstream from the expandable member, the filter having upstream and downstream sides. ### Claim 2 (depends on 1) The system of claim 1, wherein a free radical initiator in powder form is disposed on the upstream side of the filter such that as a flowable aqueous solution passes through the filter, the free radical initiator dissolves therein. ### Claim 3 (depends on 2) The system of claim 2, wherein the flowable aqueous solution comprises a first and a second water soluble polymer precursor, each water soluble polymer precursor comprising terminal functional groups. ### Claim 4 (depends on 3) The system of claim 3, wherein the initiator is a thermally activated low temperature free radical initiator. ### Claim 5 (depends on 4) The system of claim 4, wherein the flowable aqueous solution and initiator are adapted such that functional groups on the water soluble polymer precursors undergo covalent bonding to form a solid and substantially non-biodegradable material in the space inside the expandable member in situ. ### Claim 6 (depends on 2) The system of claim 2, wherein the flowable aqueous solution is a mixture of a first and a second source solution, wherein said first source solution comprises the first water soluble polymer precursor and the second source solution comprises the second water soluble polymer precursor. ### Claim 7 (depends on 2) The system of claim 2, wherein the free radical initiator is sodium, potassium or ammonium persulfate. ### Claim 8 (depends on 3) The system of claim 3, wherein the first water soluble polymer precursor is linear and the second water soluble polymer precursor is branched. ### Claim 9 (depends on 3) The system of claim 3, wherein the first water soluble polymer precursor is a linear polyethylene glycol terminally derivatized with two acrylate groups and having a molecular weight between about: about 20 and about 50 kiloDaltons, and the second water soluble polymer precursor is a branched oligomeric polyethylene glycol terminally derivatized with three acrylate groups and having a molecular weight between about 800 Daltons and about 1.2 kiloDalton. ### Claim 10 (depends on 8) The system of claim 8, wherein the molar ratio of branched polymer precursor to linear polymer precursor is between about 200:1 and about 1000:1. ### Claim 11 (depends on 8) The system of claim 8, wherein the molar ratio of branched polymer to free radical initiator is between about 2:1 and about 15:1. ### Claim 12 (depends on 2) The system of claim 2, further comprising an initiator catalyst, wherein the free radical initiator and initiator catalyst are present in about a 1:1 molar ratio. ### Claim 13 (depends on 6) The system of claim 6, further comprising an initiator catalyst, wherein either the first or second source solution comprises the initiator catalyst. ### Claim 14 A method of forming an implant by increasing the volume of an expandable member for use in treatment of an aneurysm, the method comprising: a. introducing into a tube in communication with a space inside the expandable member, or directly into the expandable member, a flowable aqueous solution comprising a first and a second water soluble polymer precursor, each water soluble polymer precursor having terminal functional groups; b. introducing into the flowable aqueous solution from step (a) a thermally activated low temperature free radical initiator in powder form, c. allowing the free radical initiator to dissolve in the flowable aqueous solution, wherein the free radical initiator is disposed on the filter such that as the flowable aqueous solution passes through the filter, the free radical initiator dissolves therein; d. allowing functional groups on the water soluble polymer precursors to undergo covalent bonding to form a solid and substantially non-biodegradable material in the space inside the expandable member. ### Claim 15 (depends on 14) The method of claim 14, further comprising: introducing an initiator catalyst into the solution from step (c). ### Claim 16 (depends on 14) The method of claim 14, wherein the flowable aqueous solution is formed by the mixture of a first and a second source solution, wherein said first source solution comprises the first water soluble polymer precursor and the second source solution comprises the second water soluble polymer precursor. ### Claim 17 (depends on 14) The method of claim 14, wherein, prior to step (a), there is introduced into a filling tube a source solution comprising the first and second water soluble polymer precursors and the initiator catalyst. ### Claim 18 (depends on 14) The method of claim 14, wherein either the first or second source solution comprises the initiator catalyst. ### Claim 19 (depends on 14) The method of claim 14, wherein the initiator catalyst is introduced before introduction of the initiator or the initiator catalyst is introduced after introduction of the initiator. ### Claim 20 A device for treatment of an aneurysm in a patient, the device comprising: an expandable member adapted to be delivered into an aneurysmal space within the patient; and a free radical initiator powder disposed in a space within said expandable member, wherein the expandable member is configured to receive through a tube in fluid communication with the space inside the expandable member, or directly into said space of the expandable member, a flowable solution comprising a first and a second polymer precursor, whereby combination of the free radical initiator with the first and second polymer precursors forms a polymer expanding the expandable member to conform to the shape of the aneurysm.