Ex Parte Tran et al

Patent Trial and Appeal BoardApr 4, 2013

11400595 (P.T.A.B. Apr. 4, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 11/400,595 04/05/2006 Tri D. Tran 05-01589 (US01) 3708 41696 7590 04/04/2013 VISTA IP LAW GROUP LLP 12930 Saratoga Avenue Suite D-2 Saratoga, CA 95070 EXAMINER BUI, VY Q ART UNIT PAPER NUMBER 3773 MAIL DATE DELIVERY MODE 04/04/2013 PAPER Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE __________ BEFORE THE PATENT TRIAL AND APPEAL BOARD __________ Ex parte TRI D. TRAN and MEDIKO ISSAKHANI __________ Appeal 2011-005073 Application 11/400,595 Technology Center 3700 __________ Before ERIC GRIMES, ULRIKE W. JENKS, and SHERIDAN K. SNEDDEN, Administrative Patent Judges. GRIMES, Administrative Patent Judge. DECISION ON APPEAL This is an appeal under 35 U.S.C. § 134 involving claims to vaso- occlusive devices. The Examiner has rejected the claims as obvious. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. STATEMENT OF THE CASE Claims 1, 2, 5-7, and 9-19 are on appeal. Claim 1, the only independent claim, reads as follows: 1. A vaso-occlusive device comprising a metallic vaso-occlusive device; and Appeal 2011-005073 Application 11/400,595 2 one or more fibrous elements attached to the metallic vaso-occlusive device at one or more locations, wherein at least one of the fibrous elements comprises a hydrogel material. Issue The Examiner has rejected all of the claims on appeal under 35 U.S.C. § 103(a) as obvious in view of Patterson.1 The Examiner finds that Patterson discloses “a vaso-occlusive coil 10 comprising a metal core …, fibrous elements/fibers 14 … coated with an bioactive layer 56, such as an expandable material such as a hydrophilic polyacrylamide” (Answer 4), as well as a “coil having a bioactive material of a polyacrylamide hydrogel” (id., emphasis omitted). The Examiner concludes that it would have been obvious to replace Patterson’s hydrophilic polyacrylamide with a polyacrylamide hydrogel because both materials would be expected to “absorb a body fluid and swell to occupy more space (in a[n] aneurysm sac, for example)” (id. at 5). Appellants contend that Patterson would not have made obvious the claimed device because Patterson does not disclose or suggest fibrous elements coated with a hydrogel material, does not describe “expanding” as one of the properties of its coatings, and describes disadvantages of hydrogel coatings in prior art devices (Appeal Br. 3-7). The issue presented is: Does the evidence of record support the Examiner’s conclusion that Patterson would have made obvious a vaso- occlusive device that includes a fibrous element comprising a hydrogel material? 1 Patterson et al., US 2006/0036281 A1, Feb. 16, 2006. Appeal 2011-005073 Application 11/400,595 3 Findings of Fact 1. Patterson discloses “vaso-occlusion devices for forming an occlusion (embolism) at a desired vascular location, in particular at the site of an aneurism” (Patterson 1, ¶ 0002). 2. Patterson’s devices are “helical wire coils preferably with enlaced fibrous materials providing an increased surface area to facilitate high rates of desired bioactions such as bioactive material release or embolic interactions between the device’s surface and the patient’s bloodstream” (id.). 3. Patterson discloses that “[e]mbolic devices, such as electrolytically detached Pt/Ir coils, have been designed with coatings that swell in aqueous solution” (id. at 1, ¶ 0005). 4. Patterson discloses that one such device “contains a polyacrylamide hydrogel attached to the Pt/Ir detachable coil. As the coil resides in blood, the hydrogel swells and occupies more space than bare metal coils, leading to higher packing densities.” (Id. at 1, ¶ 0006.) 5. Patterson discloses that placing the coating on the coil and “ensuring that the treated coil can move through a … catheter places a finite limit on the amount of hydrogel or bioactive coating applied to the coil. In general, the amount of material is limited by the surface of the coil and the delivery catheter.” (Id. at 1, ¶ 0008.) 6. Patterson discloses that “providing a large but controlled additional surface area to a helical coil device in the form of fibers enlaced into the coil provides an improved device” (id. at 2, ¶ 0015). Appeal 2011-005073 Application 11/400,595 4 7. Patterson discloses that a “bioactive material can be present in a coating applied to … fibers” (id. at 5, ¶ 0075). 8. Patterson discloses that the “bioactive material may be hydrophilic…. Examples of suitable hydrophilic compounds include polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyacrylamide and the like.” (Id.) Analysis Patterson discloses improved embolic devices that are helical wire coils enlaced with fibrous materials that provide an increased surface area to facilitate high rates of desired bioactions such as material release or embolic interactions (FF 2). Patterson discloses that the fibers can be coated with a bioactive material such as hydrophilic polyacrylamide (FF 8). Patterson discloses that, in prior art embolic coils, a polyacrylamide hydrogel attached to the coil swells in blood and occupies more space than bare metal coils, leading to higher packing densities (FF 4). In view of these disclosures, it would have been obvious to one of ordinary skill in the art to replace the hydrophilic polyacrylamide expressly disclosed by Patterson with the known polyacrylamide hydrogel coating, in order to gain the advantage of the hydrogel swelling in blood and providing higher packing densities. Appellants argue that although Patterson lists hydrophilic polyacrylamide as a bioactive material that may be coated onto fibers, “no mention is made … that [the] polyacrylamide is used in hydrogel form” (Appeal Br. 4). Appellants argue that although Patterson discloses a prior art embolic coil device with a polyacrylamide hydrogel coating, the hydrogel coating was disposed directly on the metallic coil surface (id. at 5). Appeal 2011-005073 Application 11/400,595 5 Appellants also argue that Patterson describes this prior art device as unsatisfactory because of the limited amount of hydrogel that can be loaded onto the coil (id.), and that Patterson “teaches away from hydrogel coated devices because they are difficult to deliver and do not offer enhanced function” (id. at 6). These arguments are not persuasive. Although Patterson does not expressly disclose a hydrogel coating on the fibers, Patterson does disclose hydrophilic coatings, including hydrophilic polyacrylamide, on the fibers to facilitate bioactions (FF 5 – FF 8). Patterson also discloses that a polyacrylamide hydrogel coating was known to provide the advantage of swelling and increased volume in blood (FF 3 and FF 4). Thus, providing a polyacrylamide hydrogel coating on the fibers of Patterson’s device would have required no more than the combination of elements known in the art for their known functions. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007) (“The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.”). We do not agree that Patterson teaches away from using a hydrogel coating in its device. “A reference may be said to teach away when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken by the applicant” In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994). Here, Patterson describes a problem with the prior art device that stems from the limited amount of hydrogel that could be applied to it, because of the limited surface area of the coil and the need to deliver it through a small catheter (Patterson 1, ¶ 0008). Patterson Appeal 2011-005073 Application 11/400,595 6 also states that its devices solve this problem (id. at 2, ¶¶ 0014-0015). Appellants have not provided evidence or persuasive reasoning as to why one of skill in the art would expect that using a polyacrylamide hydrogel coating on the fibers of Patterson’s device would result in a device having the problems that result from putting a hydrogel coating directly onto a metal coil. Appellants also argue that when Patterson refers to “expanding,” it “does not refer to material that physically expands as a hydrogel would. Rather, the word ‘expand’ as used in Patterson et al. refers to the ability of the fibers to increase the overall available surface area of the coil.” (Appeal Br. 4.) Appellants argue that Patterson does not refer to “any ‘expanding’ properties of the polyacrylamide bioactive material. This expanding function is not listed as one of the functions in ¶ [0077] of Patterson et al.” (Id. at 4-5.) This argument is also unpersuasive. Although Patterson does not expressly describe expanding as one of the properties provided by its bioactive materials, it states that the listed properties are only exemplary (Patterson 5, ¶ 0077) and discloses that volumetric expansion was known to provide the advantage of higher packing densities (id. at 1, ¶ 0006). Thus, based on the disclosure of the reference as a whole, modifying Patterson’s device to include a volumetrically expanding coating such as a polyacrylamide hydrogel would have been obvious to a person of ordinary skill in the art. Appeal 2011-005073 Application 11/400,595 7 Conclusion of Law The evidence of record supports the Examiner’s conclusion that Patterson would have made obvious a vaso-occlusive device that includes a fibrous element comprising a hydrogel material. Thus, we affirm the rejection of claim 1 as being obvious in view of Patterson. Claims 2, 5-7, and 9-19 have not been argued separately and therefore fall with claim 1. 37 C.F.R. § 41.37(c)(1)(iv). SUMMARY We affirm the rejection of claims 1, 2, 5-7, and 9-19 under 35 U.S.C. § 103(a). TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). AFFIRMED lp