Ex Parte Gupta et alDownload PDFPatent Trial and Appeal BoardMay 24, 201613292636 (P.T.A.B. May. 24, 2016) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 13/292,636 11/09/2011 30734 7590 05/26/2016 BAKER & HOSTETLER LLP WASHINGTON SQUARE, SUITE 1100 1050 CONNECTICUT A VE. N.W. WASHINGTON, DC 20036-5304 FIRST NAMED INVENTOR Nisha Gupta 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 ATTORNEY DOCKET NO. CONFIRMATION NO. 40792.23886 9288 EXAMINER FUBARA, BLESSING M ART UNIT PAPER NUMBER 1613 NOTIFICATION DATE DELIVERY MODE 05/26/2016 ELECTRONIC 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. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address( es): eofficemonitor@bakerlaw.com edervis@bakerlaw.com patents@bakerlaw.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte NISHA GUPTA, JOEL ROSENBLATT, and ELAINE STEINKE1 Appeal2014-003754 Application 13/292,636 Technology Center 1600 Before MELANIE L. McCOLLUM, JEFFREY N. FREDMAN, and RICHARD J. SMITH, Administrative Patent Judges. SMITH, Administrative Patent Judge. DECISION ON APPEAL This is an appeal under 35 U.S.C. § 134 involving claims to a method of fabricating a medical catheter. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. 1 According to Appellants, the Real Party in Interest is TELEFLEX MEDICAL INCORPORATED. (Br. 3.) Appeal2014-003754 Application 13/292,636 STATEMENT OF THE CASE Claims on Appeal Claims 1, 9, 10, 13-16, 19, and 20 are on appeal. 2 (Claims Appendix, Br. 17-18.) Independent claims 1 and 16 are illustrative and read as follows: 1. A method of fabricating a medical catheter, the method comprising: impregnating a base material with nitroprusside; forming the medical catheter from the base material; and coating the medical catheter with an antimicrobial agent, wherein the antimicrobial agent comprises chlorhexidine base and/or a pharmaceutically acceptable salt thereof. 16. A method of fabricating a medical catheter, the method comprising: mixing a base material with nitroprusside and an antimicrobial agent, wherein the antimicrobial agent comprises chlorhexidine base and/or a pharmaceutically acceptable salt thereof; and melt processing and extruding the mixture to fabricate the medical catheter. (Id.) Tl . ' p . . Lixamzner s "'-'"ejectzons 1. Claims 1, 9, 10, 13-15, and 19 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Barraud3 and Raad. 4 (Ans. 2.)5 2 Appellants list claim 11 as rejected rather than claim 10 because, according to Appellants, the listing of claim 10 as rejected and claim 11 as withdrawn in the Final Rejection was an error by the Examiner. (Br. 7.) However, the Examiner clarifies that claim 10 was examined and the withdrawal of claim 11 was not an error. (Ans. 2.) 3 Barraud et al., US 2009/0214674 Al, published Aug. 27, 2009, PCT filing date and 35 U.S.C. § 102(e) date of May 24, 2006 ("Barraud"). 4 Raad et al., US 2005/0197634 Al, published Sept. 8, 2005 ("Raad"). 5 All references to the Examiner's Answer are to the Subsequent Examiner's Answer to Appeal Brief dated Nov. 21, 2013. 2 Appeal2014-003754 Application 13/292,636 2. Claims 16 and 20 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Barraud, Raad, Okoh, 6 and Williams. 7 (Id. at 6.) FINDINGS OF FACT We adopt as our own the Examiner's findings and analysis concerning the scope and content of the prior art. The following findings are included for emphasis and reference convenience. FF 1. The Examiner finds that Barraud teaches a medical device, such as a catheter, that is coated or impregnated with sodium nitroprusside and at least one antimicrobial agent. (Ans. 2-3.) FF 2. The Examiner finds that Raad teaches methods for coating and impregnating medical devices, such as catheters, with antimicrobial compositions, such as gendine, which is a mixture of chlorhexidine and gentian violet. (Id. at 4.) FF 3. Raad teaches that Antiseptics such as chlorhexidine cannot attach well on their own onto the surfaces of polyvinylchloride tubes or silicone catheters ... They require an impregnating vehicle .... [U]pon combining gentian violet with chlorhexidine, the new antiseptic agent synthesized, is a potent and effective broad-spectrum antiseptic and has the additional ability to coat/impregnate various device surfaces. Gendine is unique in its ability to impregnate various device polymers, such as polyvinylchloride used in the formation of ... catheters. (Raad ii 45.) 6 Okoh et al., US 2010/0069854 Al, published Mar. 18, 2010, having a 35 U.S.C. § 102(e) date of Sept. 12, 2008 ("Okoh"). 7 Williams, US 5,707,385, issued Jan. 13, 1998 ("Williams"). 3 Appeal2014-003754 Application 13/292,636 FF 4. The Examiner finds that Okoh teaches "that chlorhexidine/fatty acid salts may be incorporated into a catheter by compounding and extrusion or any suitable hot melt process." (Ans. 7.) FF 5. The Examiner finds that Williams teaches "that an active agent, such as nitroprusside, may be loaded into a flexible membrane via melt processing ... extrusion, coating ... [and] that urethanes may be used to make the membrane, and that the membrane is delivered within the patient's vascular system by any catheter system." (Id. at 8.) ISSUES The issues presented are ( 1) whether the Examiner has made a prima facie case of obviousness based on the cited combinations of references, and (2) whether Appellants have provided evidence of unexpected results, that when weighed with the evidence of obviousness, is sufficient to support a conclusion of nonobviousness. DISCUSSION Rejection No. 1- Claim 1 The Examiner concluded that it would have been obvious to one of ordinary skill in the art to make a catheter impregnated with sodium nitroprusside and gendine, and coated with chlorhexidine, to produce the claimed invention. (Ans. 5.) Furthermore, the Examiner found that one of ordinary skill in the art would have been motivated to produce the claimed invention because ( 1) Barraud teaches the combination of sodium nitroprusside and antimicrobial agents, and that those constituents may be impregnated into the catheter and/or coating, and (2) Raad teaches "that gendine is a potent, broad-spectrum antimicrobial agent that is unique in its ability to impregnate materials while retaining activity," and that 4 Appeal2014-003754 Application 13/292,636 "chlorhexidine, a component of gendine, requires an impregnating agent in order to coat a surface." (Id. at 5-6.) Finally, the Examiner found that "Raad's teachings regarding the superior properties of gendine provide the teaching, suggestion and/or motivation" to use gendine, and that the teaching by both Barraud and Raad, that an antimicrobial agent may coat or be impregnated into the catheter material, provides a reasonable expectation of success. (Id. at 6) We find that the Examiner has satisfied the burden of showing "some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness." KSR Int'! Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007). Moreover, the Examiner has established a prima facie case of obviousness and, as discussed below, Appellants have not overcome or rebutted that prima facie case. Prima F acie Case Appellants argue a lack of motivation to modify Barraud and Raad as suggested by the Examiner because both "are directed to coating an existing catheter with antibiotic solutions and it is not possible to know beforehand which compounds can be incorporated in this manner and which cannot." (Br. 11.) We are not persuaded. Barraud teaches impregnating a catheter with nitroprusside and coating it with an antimicrobial agent (FF 1 ), and Raad teaches coating a catheter with chlorhexidine (FF 2). The use of chlorhexidine to coat the catheter of Barraud constitutes the mere substitution of one antimicrobial for another antimicrobial known in the field, yielding predictable results. See KSR, 550 U.S. at 416. Moreover, on this record, whether the impregnation or coating occurs before or after the 5 Appeal2014-003754 Application 13/292,636 formation of the catheter carries no patentable weight. See Jn re Hampel, 162 F .2d 483, 485-86 ( CCP A 194 7) ("There is nothing in the instant record which indicates that the particular order of steps produces results differing in any way from those which would be brought about if another order of steps were followed."). Furthermore, a conclusion of obviousness only requires a reasonable expectation of success, not a requirement that one "know beforehand" which compounds will work. See In re 0 'Farrell, 853 F.2d 894, 903 (Fed. Cir. 1988) ("Obviousness does not require absolute predictability of success. Indeed, for many inventions that seem quite obvious, there is no absolute predictability of success until the invention is reduced to practice."). Unexpected Results Appellants argue "the unexpected and synergistic properties of combining Chlorhexidine (CHA) and sodium nitroprusside (SNP)." (Br. 8.) In support of that argument, Appellants rely on the Gupta Declaration8 regarding the effect of the combination of SNP and CHA on the reduction of thrombus accumulation on the surface of an implanted catheter. (Deel. 3---6.) Experiment 1 Experiment 1 of the Gupta Declaration compares the thrombus accumulation on a catheter coated in a solution containing 2% chlorhexidine di-acetate (CHA) and an uncoated catheter. (Id. at 4--5.) According to the Gupta Declaration, the results of that experiment show about 41 % less 8 Declaration ofNisha Gupta under 37 C.F.R. § 1.132 dated August 16, 2012 ("Gupta Declaration"). 6 Appeal2014-003754 Application 13/292,636 thrombus accumulation on the CHA coated catheter as compared to the uncoated catheter. (Id.) Experiment 2 Experiment 2 compares the thrombus accumulation on an uncoated polyurethane extrusion, a polyurethane resin compounded with 1 % sodium nitroprusside (SNP) and then melt extruded (referred to as SNP alone), and SNP extrusions coated in a solution containing 2.5% CHA (referred to as SNP +CHA). (Id. at 5.) The results are illustrated in Figure 2 below. 120 -a ~ 100 ~ 80 8 ll .u. i 40 :::> 'ti ~ Thrombus Accumulation 100 U1woat~d 26.8 '--~-· -··-~J--"~---, SNPA!one oevlees SNP-t. CHA Figure 2: Uncoated control sample with no CHA or SNP compared to sample with SNP alone and a sample with SNP+CHA. According to the Gupta Declaration, the results of this experiment reflect about 73% less thrombus accumulation on the SNP alone samples, and about 91 % less thrombus accumulation on the SNP + CHA samples. 7 Appeal2014-003754 Application 13/292,636 (Deel. 5.) Analysis We are not persuaded that Appellants' evidence rebuts the prima facie case of obviousness for at least the following reasons. Unexpected results must be shown to be unexpected compared with the closest prior art. In re Baxter Travenol Labs., 952 F.2d 388, 392 (Fed. Cir. 1991) (citing In re De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984)). In this case, the closest prior art is Barraud's combination of SNP and an antimicrobial agent, such as tobramycin. (See Barraud i-fi-f 128-131; FIGS. 4---6.) Thrombus accumulation results for a catheter having the combination taught by Barraud, in comparison to the claimed combination, are not present in the record before us. Evidence of nonobviousness must also be commensurate in scope with the claims. In re Lindner, 457 F .2d 506, 508 (CCP A 1972). Here, the claims are not limited to an amount of nitroprusside or chlorhexidine, yet the experiments were carried out using 1 % SNP and 2% or 2.5% CHA. (Deel. 3---6.) The results are thus not commensurate in scope with the claims. Appellants' test results show about 41 % less thrombus accumulation on the CHA alone samples, about 73% less thrombus accumulation on the SNP alone samples, and about 91 % less thrombus accumulation on the SNP + CHA samples. (Deel. 3---6.) The combination of SNP + CHA thus reflects a difference in degree of thrombus accumulation compared to each agent alone, rather than a difference in kind. 9 "[D]ifferences in degree" of a 9 SNP was known to reduce or prevent platelet aggregation. (Spec. 3, 1. 21- 4, 1. 2.) 8 Appeal2014-003754 Application 13/292,636 known and expected property are not as persuasive in rebutting obviousness as differences in "kind" (i.e., a new property dissimilar to the known property). Bristol-Myers Squibb Co. v. Teva Pharms. USA, Inc., 752 F.3d 967, 977 (Fed. Cir. 2014); see also In re Merck, 800 F.2d 1091, 1099 (Fed. Cir. 1986) (finding evidence that the new drug was a more potent sedative and had a stronger anticholinergic effect than the prior art was insufficient to outweigh the evidence of obviousness). Finally, we acknowledge Appellants' reliance on "synergism." (Br. 8-10.) However, even if we agreed that the claimed method provided synergistic results, more would be required to show nonobviousness since synergism per se may be expected or unexpected. See In re Diamond, 360 F.2d 214, 218 (CCPA 1966). On balance, we are not persuaded that the evidence of unexpected results is sufficient to overcome the evidence favoring obviousness. 10 The rejection of claim 1 is affirmed. Rejection No. 2- Claim 16 The Examiner provides a detailed basis for concluding that it would have been obvious to one of ordinary skill in the art to use melt processing and extrusion to produce a catheter as recited in claim 16, and that one of ordinary skill in the art would have been motivated to do so with a reasonable expectation of success. (Ans. 8-9.) Accordingly, we find that 10 We also recognize, but are unpersuaded by, Appellants' argument of "(anticipated) commercial success" and "the prospect of commercial success." (Br. 9-10.) While perhaps a novel argument, Appellants fail to provide any evidence of actual "commercial success." See, e.g., In re Huang, 100 F.3d 135, 139--40 (Fed. Cir. 1996). 9 Appeal2014-003754 Application 13/292,636 the Examiner has satisfied the burden of showing "some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness." KSR, 550 U.S. at 418. Appellants rely on the same arguments and evidence as set forth above in connection with claim 1 (Br. 12-14), and we are similarly unpersuaded for the reasons stated above. In addition, Appellants argue that, while Okoh and Williams both disclose melt processing, "neither discloses the combination of mixing the polymer, nitroprusside and chlorhexidine together and then melt-processing." (Br.13-14.) On this record, however, whether the components are pre-mixed or not carries no patentable weight. See Hampel, 162 F.2d at 485-86. Dependent Claims Appellants argue that dependent claims 9, 11 [sic, 10], 13-15, 19, and 20 "define patentable subject matter at least by virtue of their dependency as well as for the additional features they recite." (Br. 16.) However, because Appellants present no additional arguments with respect to the rejection of those claims, we affirm their rejections as well. See Hyatt v. Dudas, 551 F.3d 1307, 1314 (Fed. Cir. 2008). CONCLUSION OF LAW A preponderance of evidence of record supports the Examiner's conclusion that claims 1, 9, 10, 13-16, 19, and 20 are obviousness under 35 U.S.C. § 103(a). Furthermore, Appellants have not provided evidence of unexpected results that, when weighed with the evidence favoring obviousness, shows that the claims would have been nonobvious. SUMMARY We affirm the rejections of all claims on appeal. 10 Appeal2014-003754 Application 13/292,636 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 11 Copy with citationCopy as parenthetical citation