Ex Parte Ohishi et al

Patent Trial and Appeal BoardMar 7, 2016

12757947 (P.T.A.B. Mar. 7, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 121757,947 04/09/2010 23373 7590 03/09/2016 SUGHRUE MION, PLLC 2100 PENNSYLVANIA A VENUE, N.W. SUITE 800 WASHINGTON, DC 20037 FIRST NAMED INVENTOR Takahiro Ohishi 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. Ql 16692 3857 EXAMINER KATAKAM, SUDHAKAR ART UNIT PAPER NUMBER 1671 NOTIFICATION DATE DELIVERY MODE 03/09/2016 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): PPROCESSING@SUGHRUE.COM sughrue@sughrue.com USPTO@sughrue.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte TAKAHIRO OHISHI, HIROKAZU NANBA, MASANOBU SUGA W ARA, MASASHI IZUMIDA, TATSUYA HONDA, KOHEI MORI, SATOHIRO YANAGISAWA, NOBUO NAGASHIMA, and KENJI INOUE Appeal2013-006681 Application 12/757,947 Technology Center 1600 Before JEFFREYN. FREDMAN, ULRIKE W. JENKS, and JOHN G. NEW, Administrative Patent Judges. FREDMAN, Administrative Patent Judge. DECISION ON APPEAL This is an appeal 1 under 35 U.S.C. Â§ 134 involving claims to a D- or L-optically active 5-methyl-5-thiomethylhydantoin derivative. The Examiner rejected the claims as obvious. We have jurisdiction under 35 U.S.C. Â§ 6(b). We affirm. 1 Appellants identify the Real Party in Interest as Harbor Therapeutics, Inc. (see App. Br. 1 ). Appeal2013-006681 Application 12/757,947 Statement of the Case Background "The present invention relates to a process for producing an optically active L- or D-a-methylcysteine derivative or its salt which is useful as an intermediate for pharmaceutical products" (Spec. 1, 11. 6-9). The Claims Claims 13 and 14 are on appeal and are reproduced below: 13. AD- or L-optically active 5-methyl-5-thiomethylhydantoin derivative represented by formula (2): or formula (7): ol"-~ H~,~~R' ol"-~ H~><' ,~O ''' 1-SR1 (2) (7) (wherein R1 is a tertiary alkyl group having 4 to 15 carbon atoms), or its salt. 14. The compound according to claim 13, wherein the tertiary alkyl group is a tert-butyl group. The Issue The Examiner rejected claims 13 and 14 under 35 U.S.C. Â§ 103(a) as obvious over Tahara2 or Oh3 (Ans. 6-7). 2 Tahara et al., Studies on a-Alkyl-a -amino acids Part I. Synthesis of S-Alkyl-2-methyl-DL_cysteines, 55 Agr. Biol. Chem. 53-57 (1971). 2 Appeal2013-006681 Application 12/757,947 The Examiner finds that Tahara and Oh teach 5-methyl-5- thiomethylhydantoin derivatives of formulas (2) and (7) but are "deficient in the sense that both fail to teach optically active Dor L of 5-methyl-5- thiomethylhydantoin derivative" (Ans. 6). The Examiner finds that "a person of ordinary skill in the art would have expected, namely, that the racemic mixture of the prior art may be separate ( +) and (-) enantiomers" (Ans. 6). The Examiner finds that "technology for separating optical isomers is well known in the art. Separation of structurally similar compounds to applicants claimed compounds are also known in the art [see Background Art of specification]" (Final Act. 2). The Examiner finds that a "skilled person would be motivated to obtain a (D)- or L-optically active forms of 5-methyl-5-thiomethylhydantoin derivative represented by formula (2) or (7), because of their expected different pharmacological activity over the racemic mixture or explore economic advantages over the other" (Ans. 7). Appellants contend that "the mere fact that a compound has enantiomers is not sufficient to enable the separation of the enantiomers where the reference did not teach how to obtain the enantiomer" (App. Br. 4). Appellants contend that "[n]obody could accomplish the separation for the racemic compound at the priority date of the present application" (App. Br. 10). 3 Oh et al., Synthesis of new hydantoin-3-acetic acid derivatives, 9 Bull. Korean Chem. Soc. 231-5 (1988) (abstract only). 3 Appeal2013-006681 Application 12/757,947 We find that the Examiner has the better position. Claims 13 and 14 are drawn to any amount of an optically pure D- or L- 5-methyl-5- thiomethylhydantoin derivative of the claimed formula. As the Examiner notes (see Final Act. 2), the admitted prior art in the Background of the Specification acknowledges six different "[k ]nown processes for producing an optically active L- or D-a-methylcysteine derivative" (see Spec. 1, 1. 12 to 2, 1. 12). While the Specification acknowledges difficulties "in stirring a crystallization solution and isolating the solid" resulting in a process that is "unsuitable for industrial production" (Spec. 3, 11. 21-24), the instant claims do not require the purification of any particular amount of product nor industrial production, but rather require isolation of either optically active enantiomeric form from the racemic mixture. While we agree with Appellants that Adamson does not create a per se rule that optically active forms of known racemic compounds are necessarily obvious (see App. Br. 4), Adamson does evidence that "racemates may be resolved into their laevo- and dextro-isomers by one of several methods." In re Adamson, 275 F.2d 952, 954 (CCPA 1960). This finding is consistent with the teachings in the Specification relied upon by the Examiner of six different "[k ]nown processes for producing an optically active L- or D-a- methylcysteine derivative" (see Spec. 1, 1. 12 to 2, 1. 12; cf Final Act. 2). Sanofi-Synthelabo is consistent with this analysis, teaching that "the chemical literature shows at least ten separation techniques" for enantiomers, though recognizing that "it cannot be known in advance which, if any, technique might work." Sanofi-Synthelabo v. Apotex, Inc. 550 F.3d 1075, 1081 (Fed. Cir. 2008). 4 Appeal2013-006681 Application 12/757,947 The current facts are unlike those in Sanofi-Synthelabo, where the nonobviousness of the dextrorotatory enantiomer was ultimately based on the unexpected result of an enantiomer "having absolute stereoselectivity as to both the favorable antiplatelet activity and the unfavorable neurotoxicity." Id. at 1090. Appellants have provided no evidence that either the D- or the L- form of 5-methyl-5-thiomethylhydantoin have any unexpected or beneficial properties whatsoever. Indeed, unlike Sanofi-Synthelabo that solely claimed the D- enantiomer, even if one of the two enantiomers had an unexpected result not shown in the Specification or evidenced by Appellants, the result would not be commensurate in scope with claim 13 that is drawn to either the D- or the L- enantiomer. We recognize, but find unpersuasive, Appellants' contention that "only a racemic compound was known before the present application was disclosed, even though the racemic compound was reported thirty years ago. Appellants submit that this fact shows the difficulty of obtaining the optically active compound of the present invention" (App. Br. 5). The "mere age of the references is not persuasive of the unobviousness of the combination of their teachings, absent evidence that, notwithstanding knowledge of the references, the art tried and failed to solve the problem." In re Wright, 569 F.2d 1124, 1127 (CCPA 1977). Appellants have presented no evidence that there were any failed efforts made in the prior art to separate the enantiomers of hydantoin. We recognize, but find unpersuasive, Appellants' contention that "the separated hydantoin derivative (2) has an optical purity of 100% (see Example 1, at page 55). This evidence in the specification should have been 5 Appeal2013-006681 Application 12/757,947 considered by the Examiner, and is unexpected in view of the cited prior art" (Reply Br. 6). The Specification never identifies this example as unexpected. Therefore, Appellants only have attorney argument, not evidence, for any unexpected results. See In re Soni, 54 F.3d 746, 750 (Fed. Cir. 1995) ("It is well settled that unexpected results must be established by factual evidence. Mere argument or conclusory statements ... [do] not suffice.") SUMMARY In summary, we affirm the rejection of claim 13 under 35 U.S.C. Â§ 103(a) as obvious over Tahara or Oh. Claim 14 falls with claim 13. 37 C.F.R. Â§41.37(c)(l)(iv). No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. Â§ 1.136(a). AFFIRMED 6