# US 11,931,484 B2 · Composite stent having multi-axial flexibility and method of manufacture thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,931,484 B2 - Document ID: US11931484B2 - Status: Granted - Kind: B2 - Application number: 17/150,194 - Filed: 2021-01-15 - Published: 2021-05-06 - Granted: 2024-03-19 - Earliest claimed: 2008-06-20 - Assignees: Razmodics LLC - Applicants: Razmodics LLC - Inventors: Kamal Ramzipoor; Richard J. Saunders - Web page: https://patentgrep.com/patent/US11931484B2 ## CPC - A61L 31/148: {Materials at least partially resorbable by the body} - A61F 2/07: Stent-grafts - A61F 2/82: Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents (stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07) - A61F 2/915: with bands having a meander structure, adjacent bands being connected to each other - A61L 31/04: Macromolecular materials - 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 31/16: Biologically active materials, e.g. therapeutic substances {(A61L31/047 takes precedence)} - B29C 41/003: {characterised by the choice of material} - B29C 41/14: Dipping a core {(B29C41/10 takes precedence)} - A61F 2/24: Heart valves {; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices; Valves implantable in the body} - A61F 2002/30062: {(bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive} - A61F 2002/30535: {Special structural features of bone or joint prostheses not otherwise provided for} - A61F 2002/828: {Means for connecting a plurality of stents allowing flexibility of the whole structure} - A61F 2002/91558: {connected peak to peak} - A61F 2210/0004: bioabsorbable - A61F 2210/0019: operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation - A61F 2240/004: Using a positive or negative model, e.g. moulds - B29K 2105/0035: {Medical or pharmaceutical agents} - B29K 2995/0056: Biocompatible, e.g. biopolymers or bioelastomers - B29L 2031/7532: {Artificial members, protheses} - 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) - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract A bioabsorbable composite stent structure, comprising bioabsorbable polymeric ring structures which retain a molecular weight and mechanical strength of a starting substrate and one or more interconnecting struts which extend between and couple adjacent ring structures. The ring structures can have a formed first diameter and being radially compressible to a smaller second diameter and re-expandable to the first diameter. The ring structures can comprise a base polymeric layer. The interconnecting struts can be formed from a polymer blend or co-polymer of poly-L-lactide (PLLA) and an elastomeric polymer. The interconnecting struts each can have a width that is less than a circumference of one of the ring structures. The adjacent ring structures can be axially and rotationally movable relative to one another via the interconnecting struts. The interconnecting struts can also be bioabsorbable. ## Claims ### Claim 1 A method of forming a composite stent or scaffold structure, comprising: forming a base polymeric substrate via dip-coating, wherein the base polymeric substrate comprises one or more segments reduced in diameter along the base polymeric substrate; coating the base polymeric substrate with one or more polymer layers, wherein at least one of the one or more polymer layers comprises an elastomeric polymer; and further processing the base polymeric substrate coated with the one or more polymer layers into a stent or scaffold structure. ### Claim 2 (depends on 1) The method of claim 1, wherein forming the base polymeric substrate further comprises forming the base polymeric substrate upon a mandrel. ### Claim 3 (depends on 2) The method of claim 2, wherein forming the base polymeric substrate further comprises dip-coating the mandrel in a polymeric solution comprising a bioabsorbable or biodegradable polymeric material. ### Claim 4 (depends on 1) The method of claim 1, wherein further processing the base polymeric substrate comprises forming at least a first ring structure and a second ring structure connected by an interconnecting strut, wherein the first ring structure, the second ring structure, and the interconnecting strut are part of the stent or scaffold structure. ### Claim 5 (depends on 4) The method of claim 4, wherein the interconnecting strut has a width that is less than a circumference of the first ring structure and the second ring structure. ### Claim 6 (depends on 1) The method of claim 1, wherein the elastomeric polymer is polycaprolactone (PCL). ### Claim 7 (depends on 6) The method of claim 6, wherein the elastomeric polymer is part of a polymer blend or co-polymer. ### Claim 8 (depends on 7) The method of claim 7, wherein the elastomeric polymer is 1% to 50% of the polymer blend or co-polymer. ### Claim 9 (depends on 7) The method of claim 7, wherein the polymer blend or co-polymer comprises poly-L-lactide (PLLA). ### Claim 10 (depends on 7) The method of claim 7, wherein the polymer blend or co-polymer has a glass transition temperature of between 50° C. and 65° C. ### Claim 11 (depends on 1) The method of claim 1, wherein the stent or scaffold structure comprises a plurality of ring structures connected by interconnecting struts. ### Claim 12 (depends on 11) The method of claim 11, wherein the interconnecting struts are arranged along a length of the stent or scaffold structure in a circumferentially alternating manner between immediately adjacent ring structures. ### Claim 13 (depends on 11) The method of claim 11, wherein the plurality of ring structures are spaced closer to one another along a first portion than along a second portion of the stent or scaffold structure. ### Claim 14 (depends on 11) The method of claim 11, wherein a terminal ring structure of the plurality of ring structures is relatively more flexible than a remainder of the ring structures. ### Claim 15 A method of forming a composite stent or scaffold structure, comprising: forming a base polymeric substrate via dip-coating; processing the base polymeric substrate by forming one or more segments reduced in diameter along the base polymeric substrate; coating the base polymeric substrate with a polymer layer comprising an elastomeric polymer; and further processing the base polymeric substrate coated with the polymer layer comprising the elastomeric polymer into a stent or scaffold structure. ### Claim 16 (depends on 15) The method of claim 15, wherein coating the base polymeric substrate further comprises coating the base polymeric substrate with the polymer layer comprising the elastomeric polymer such that the elastomeric polymer forms within or coats the one or more segments. ### Claim 17 (depends on 15) The method of claim 15, wherein further processing the base polymeric substrate comprises forming at least a first ring structure and a second ring structure connected by an interconnecting strut, wherein the interconnecting strut has a width that is less than a circumference of the first ring structure and the second ring structure, and wherein the first ring structure, the second ring structure, and the interconnecting strut are part of the stent or scaffold structure. ### Claim 18 A method of forming a composite stent or scaffold structure, comprising: forming a base polymeric substrate; overlaying a plurality of ring structures upon the base polymeric substrate, wherein the plurality of ring structures are separated from one another and positioned axially upon the base polymeric substrate, wherein the plurality of ring structures retain a molecular weight and mechanical strength of a starting substrate; coating the base polymeric substrate overlaid with the plurality of ring structures with one or more additional polymeric layers; and processing the coated base polymeric substrate overlaid with the plurality of ring structures into a stent or scaffold structure. ### Claim 19 (depends on 18) The method of claim 18, wherein the base polymeric substrate comprises an elastomeric polymer. ### Claim 20 (depends on 18) The method of claim 18, wherein adjacent ring structures of the plurality of ring structures are separated from one another by a distance of between 1 mm to 10 mm.