ROCHE DIABETES CARE, INC.Download PDFPatent Trials and Appeals BoardSep 9, 20212021004098 (P.T.A.B. Sep. 9, 2021) Copy Citation 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. 16/289,933 03/01/2019 Nathan Allen CARRINGTON 655-14421 7144 180598 7590 09/09/2021 Brannon Sowers & Cracraft PC- Roche 47 South Meridian Street Suite 400 Indianapolis, IN 46204 EXAMINER NOGUEROLA, ALEXANDER STEPHAN ART UNIT PAPER NUMBER 1795 NOTIFICATION DATE DELIVERY MODE 09/09/2021 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): docket@bscattorneys.com pair_roche@firsttofile.com uspto@dockettrak.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE _________ BEFORE THE PATENT TRIAL AND APPEAL BOARD __________ Ex parte NATHAN ALLEN CARRINGTON, STACY HUNT DUVALL, and LEON SCOTT VAN DYKE __________ Appeal 2021-004098 Application 16/289,933 Technology Center 1700 ___________ Before ADRIENE LEPIANE HANLON, BEVERLY A. FRANKLIN, and DONNA M. PRAISS, Administrative Patent Judges. HANLON, Administrative Patent Judge. DECISION ON APPEAL A. STATEMENT OF THE CASE The Appellant1 filed an appeal under 35 U.S.C. § 134(a) from an Examiner’s decision finally rejecting claims 25–45. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. The Appellant identifies the real party in interest as Roche Diabetes Care, Inc. Appeal Brief dated January 27, 2021 (“Appeal Br.”), at 2. Appeal 2021-004098 Application 16/289,933 2 The Appellant’s invention is said to be directed to compositions, devices, and uses in the analytical detection and/or quantification of an analyte, such as glucose. Spec. ¶ 2. The Appellant discloses that “[i]t has been surprisingly discovered . . . that zwitterionic buffers may be included in a wide variety of reagent systems, and may improve the kinetics of glucose detection and/or measurement.” Spec. ¶ 6. Independent claim 25 is reproduced below from the Claims Appendix to the Appeal Brief. The limitation at issue is italicized. 25. An electrochemical sensor comprising an electrode, and a dried residue covering at least a portion of the electrode, where the dried residue comprises (a) one or more enzymes selected from the group consisting of glucose dehydrogenases, glucose oxidoreductases, and combinations thereof; (b) optionally one or more co-factors, co- enzymes, or a combination thereof for the one or more enzymes; (c) one or more mediators, mediator precursors, or a combination thereof, wherein at least one mediator or mediator precursor is aqueous soluble; (d) one or more zwitterionic buffers; and (e) an hydratable matrix comprising one or more gelling agents. Appeal Br. 35. The Examiner maintains the following grounds of rejection on appeal: (1) claims 25, 27, and 30–45 under 35 U.S.C. § 103(a) as unpatentable over Nagakawa2 in view of Bhullar;3 (2) claims 26 and 28 under 35 U.S.C. § 103(a) as unpatentable over Nagakawa in view of Bhullar, further in view of Yamoaka;4 and 2 US 2007/0053790 A1, to Nagakawa et al., published March 8, 2007 (“Nagakawa”). 3 US 2005/0019212 A1, to Bhullar et al., published January 27, 2005 (“Bhullar”). 4 US 7,776,575 B2, to Yamoaka et al., issued August 17, 2010 (“Yamoaka”). Appeal 2021-004098 Application 16/289,933 3 (3) claim 29 under 35 U.S.C. § 103(a) as unpatentable over Nagakawa in view of Bhullar, further in view of Inamori.5 B. DISCUSSION 1. Rejection (1) a. Claims 25, 27, and 30–43 The Examiner finds Nagakawa teaches an electrochemical sensor comprising a dried residue that includes components (a)–(d) recited in claim 25. Final Act. 3.6 The Examiner finds Nagakawa does not disclose that the dried residue includes claimed component (e), i.e., “an hydratable matrix comprising one or more gelling agents.” Final Act. 4; Appeal Br. 35. Nonetheless, the Examiner finds Bhullar discloses a gelling agent as claimed. Final Act. 4. More specifically, the Examiner finds Bhullar discloses a reagent similar to the reagent disclosed in Nagakawa (corresponding to the claimed dried residue) that includes a variety of adjuvants to enhance the reagent properties or characteristics. For example, the composition may include adjunct materials to facilitate the placement of the reagent composition onto the test strip and to improve its adherence to the strip. The composition can also include materials to increase its rate of hydration and/or increase its influence on the capillary action to fill the chamber with the test sample. Examples of addjunct [sic] materials to be used with the reagent composition include thickeners, viscosity modulators, film formers, stabilizers, buffers, detergents, gelling agents, fillers, film opening agents, coloring agents, and agents endowing thixotropy. Bhullar ¶ 163 (emphasis added); see also Final Act. 4. The Examiner concludes that it would have been obvious to one of ordinary skill in the art to add Bhullar’s gelling agent adjuvants to the reagent layer of 5 US 2008/0248514 A1, to Inamori et al., published October 9, 2008 (“Inamori”). 6 Final Office Action dated May 27, 2020. Appeal 2021-004098 Application 16/289,933 4 Nagakawa’s sensor in order to enhance its reagent properties or characteristics as disclosed in Bhullar paragraph 163. Final Act. 4–5. The Appellant argues that Bhullar, in paragraph 63, “does not indicate which ‘reagent properties or characteristics’ will be enhanced by a gelling agent.” Appeal Br. 11. Therefore, the Appellant argues that one of ordinary skill in the art would not have been motivated to add a gelling agent to the reagent layer of Nagakawa’s sensor as proposed by the Examiner. Appeal Br. 8. The Appellant’s argument is not persuasive of reversible error. Bhullar discloses that “[t]he reagent composition can . . . include a variety of adjuvants to enhance the reagent properties or characteristics” and discloses that exemplary materials include gelling agents. Bhullar ¶ 163; see also Appeal Br. 10 (recognizing that the “possible adjuvants” disclosed in Bhullar include gelling agents). Thus, we find Bhullar teaches that adjuvants, including gelling agents, will enhance the properties or characteristics of a reagent. We find that enhancing reagent properties or characteristics alone is sufficient motivation to add a gelling agent to Nagakawa’s reagent, which is used for the same purpose as Bhullar’s reagent.7 See Final Act. 17 (finding that “[a]t the very least, one of ordinary skill would recognize that adding the gelling agent of Bhullar to the reagent of Nagakawa would provide ‘enhancing the reagent properties or characteristics’”). To the extent that Bhullar does not expressly “indicate which ‘reagent properties or characteristics’ will be enhanced by a gelling agent,”8 on this record, it appears that one of ordinary skill in the art would have understood the 7 Bhullar discloses that the invention is directed to evaluating a sample fluid, such as blood, for a target analyte, such as glucose. Bhullar ¶ 49. 8 Appeal Br. 11. Appeal 2021-004098 Application 16/289,933 5 function(s) of a gelling agent in Bhullar’s reagent. In that regard, similar to the disclosure in paragraph 163 of Bhullar, the Appellant discloses: The reagent composition may also include a variety of adjuvants to enhance the reagent properties or characteristics. For example, the composition may include adjunct materials to facilitate the placement of the reagent composition onto the test strip and to improve its adherence to the strip. The composition can also include materials to increase its rate of hydration and/or its increase its influence on the capillary action to fill the chamber with the test sample. Additionally, the reagent composition can include components selected to enhance the physical properties of the resulting dried reagent composition, and the uptake of a liquid test sample for analysis. Examples of adjuvant materials to be used with the reagent composition include thickeners, viscosity modulators, film formers, stabilizers, buffers, detergents, gelling agents, fillers, film opening agents, coloring agents, and agents endowing thixotropy. The adjuvant materials or components can impact the application, reproducibility and physical properties of the reagent composition. Spec. ¶ 30 (emphasis added). Notably, the Appellant does not disclose the specific property or characteristic of the reagent that is enhanced by the gelling agent. The Appellant also argues that an object of Nagakawa’s invention “is to provide an analyzing tool which is capable of shortening the analysis time.” Appeal Br. 15 (quoting Nakagawa ¶ 8) (emphasis added). However, the Appellant argues that the addition of a gelling agent is contrary to Nagakawa’s objective because a gelled reaction phase would be more viscous than the corresponding ungelled reaction phase and thus slow dissolution of the reagent portion and slow diffusion of both the reagent and the glucose. Appeal Br. 19–20. For that reason, the Appellant argues that one of ordinary skill in the art would not have been motivated to add a gelling agent to Nagakawa’s reagent layer as proposed by the Examiner. Appeal Br. 21. Appeal 2021-004098 Application 16/289,933 6 On this record, the Appellant does not direct us to any evidence establishing that the addition of a gelling agent to Nagakawa’s dried reagent would have been expected to slow dissolution of the reagent and slow diffusion of both the reagent and the glucose whereby the objectives of Nagakawa cannot be achieved. See In re Schulze, 346 F.2d 600, 602 (CCPA 1965) (“Argument in the brief does not take the place of evidence in the record.”). Nagakawa discloses that reaction time may be shortened by dividing the reagent into two portions. Nagakawa ¶ 66; Nagakawa Fig. 3 (illustrating reagent portions 51 and 52); see also Appeal Br. 16. Nagakawa also discloses that measurement time may be shortened by reducing the height (facing distance) of the capillary. Nagakawa ¶¶ 82, 85; Nagakawa Fig. 3 (illustrating capillary 4); see also Appeal Br. 16. Thus, Nagakawa does not attribute a shortened reaction time to any components that are either included or not included in the reagent composition. In fact, Nagakawa contemplates using high viscosity materials in the disclosed sensor. Nagakawa discloses: Preferably, the facing distance may be no greater than 100 µm, and more preferably, no greater than 75 µm. On the other hand, the facing distance may be no smaller than 30 µm. This is because, when the facing distance is excessively small, a sample containing solid components, like blood containing blood cells, or a sample having a high viscosity cannot move smoothly through the flow path. Nagakawa ¶ 24 (emphasis added). Moreover, the teachings of Bhullar support a finding that the addition of a gelling agent to Nagakawa’s reagent layer, as disclosed in Bhullar, would not run counter to the objectives disclosed in Nagakawa. See Final Act. 11 (finding that “there is no reason to believe that the adjuvants [e.g., gelling agents] of Bhullar will destroy the function of Nagakawa”). In particular, Bhullar discloses that “it is Appeal 2021-004098 Application 16/289,933 7 preferable that the reagent layer be thin and uniform” because the “liquid test sample will hydrate or dissolve the thin reagent layer more quickly.”9 Bhullar ¶ 97; see also Bhullar ¶ 3 (disclosing that “[c]urrent trends in test strips require smaller test samples and faster analysis times”). Bhullar also discloses that “[t]he control and reproducibility of the quantity, location, width, thickness, and other properties of the reagent layer become more important as . . . test time diminishes.”10 Bhullar ¶ 162 (emphasis added). Therefore, Bhullar discloses that including materials, such as gelling agents, that specifically enhance the physical characteristics of the reagent is desirable. Bhullar ¶¶ 162–163. In an attempt to rebut the prima facie case of obviousness, the Appellant argues that the claimed invention exhibits unexpected results. More specifically, the Appellant argues that “the claimed electrochemical sensors show unexpected properties compared to the prior art, including improved kinetics of glucose detection and measurement, and improved temperature and storage stability.” Appeal Br. 23. For support, the Appellant directs our attention to Figures 1–3 of the instant Application which are said to show the time to maximum signal for several sensors. More specifically, Figure 1 is said to show “the kinetics curves for DC 9 Similar to Bhullar, the Appellant discloses that a liquid test sample hydrates or dissolves a thin reagent layer more quickly. Spec. ¶ 73. Conversely, the Appellant discloses that a thick reagent layer takes more time for a liquid test sample to hydrate or dissolve the reagent. Id. Thus, it would appear that the thickness of the Appellant’s reagent layer rather than the presence of some amount of a gelling agent dictates the rate of dissolution in the Appellant’s invention. 10 According to the Appellant, Bhullar’s sensor reaches a maximum signal in approximately 4.0 seconds whereas Nagakawa’s sensor reaches maximum absorbance in about 5 seconds or greater. Appeal Br. 24, 28. Thus, it would appear that Bhullar’s test time is faster than Nagakawa’s test time. Appeal 2021-004098 Application 16/289,933 8 response (µA) versus time (ms) for three illustrative sensors based on a PQQ-GDH enzyme using reagents that include (A) a PIPES buffer,11 (B) a β-glycerophosphate buffer, and (C) a phosphate buffer.” Spec. ¶ 12; see also Appeal Br. 24. The Appellant contends that sensor (A) corresponds to the claimed sensor and sensors (B) and (C) correspond to Bhullar’s sensors. Appeal Br. 24. The Appellant contends that sensor (A) “reaches the DC peak maximum at approximately 2.3 seconds” and sensors (B) and (C) “reach the DC peak maxima at approximately 4.0 seconds.” Appeal Br. 24. Figure 2 of the instant Application is said to show “the kinetics curves for DC response (µA) versus time (ms) for two illustrative sensors based on a FAD- GDH enzyme using reagents that include (A) a PIPES buffer, and (B) a phosphate buffer.” Spec. ¶ 13; Appeal Br. 25. Figure 3 of the instant Application is said to show “the kinetics curves for DC response (µA) versus time (ms) for three illustrative sensors using reagents that include (A) a MOPS buffer12 at a pH of 7.5, (B) a β-glycerophosphate buffer at a pH of 7.5, and (C) a β-glycerophosphate buffer at a pH of 7.0.” Spec. ¶ 14; Appeal Br. 26. The Appellant contends that Figures 2 and 3 show that sensor (A) reaches the DC peak maximum “at approximately 1.43 seconds (FIG. 2) and approximately 2.0 seconds (FIG. 3)” and sensors (B) and (C) reach the DC peak maximum at “approximately 3.1 and 3.5 seconds, respectively (FIG. 3).” Appeal Br. 26. The Appellant does not identify the DC peak maximum for sensor (B) in Figure 2. 11 The Appellant discloses that PIPES is a zwitterionic buffer. Spec. ¶ 20. 12 The Appellant discloses that MOPS is a zwitterionic buffer. Spec. ¶ 20. Appeal 2021-004098 Application 16/289,933 9 Based on the foregoing, the Appellant argues that “Appellant’s sensors show unexpected results, and are almost twice as fast as those described in Bhullar.” Appeal Br. 26. “[A]n applicant relying on comparative tests to rebut a prima facie case of obviousness must compare his claimed invention to the closest prior art.” In re De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984). The Appellant identifies Bhullar as the closest prior art.13 See Appeal Br. 24–26. Bhullar discloses that K2HPO4 and KH2PO4 are used as buffers. See Bhullar, Table 1. The buffers in sensors (B) and (C), however, are identified as β-glycerophosphate buffers and phosphate buffers. Spec. ¶¶ 12–14. On this record, it is unclear whether the buffers disclosed in Bhullar and the buffers in sensors (B) and (C) are the same. Moreover, “objective evidence of non-obviousness must be commensurate in scope with the claims which the evidence is offered to support.” In re Tiffin, 448 F.2d 791, 792 (CCPA 1971). In this case, claim 25 recites that the residue or reagent in the sensor comprises, inter alia, a gelling agent(s), but it does not appear that the sensors tested include a gelling agent. Appeal Br. 35; Spec. ¶ 77. The Appellant argues that Appellant’s working Examples include Keltrol F which is a gelling agent. Reply Br. 17.14 Keltrol F, however, is identified as a “thickening agent,” not a gelling agent, in the Appellant’s Specification. Spec. ¶ 77; see also Bhullar ¶ 165 (identifying Keltrol F as a thickener). The Appellant 13 The Examiner, on the other hand, identifies Nagakawa as the closest prior art. See Final Act. 21–22. The Examiner finds Nagakawa discloses a sensor comprising, inter alia, GDH as an enzyme, PQQ as a coenzyme, and PIPES as the zwitterionic buffer. Final Act. 3; see also Nagakawa ¶ 97. The Appellant, however, argues that Nagakawa’s Examples are directed to colorimetric sensors rather than electrochemical sensors as claimed. Appeal Br. 27. 14 Reply Brief dated June 16, 2021. Appeal 2021-004098 Application 16/289,933 10 discloses that thickening agents and gelling agents are different adjuvant materials. Spec. ¶ 30 (disclosing that examples of adjuvant materials include thickeners and gelling agents); see also Appeal Br. 35–36 (reciting in claim 33 that the dried residue recited in claim 25 further comprises one or more adjuvants selected from the group consisting of, inter alia, “thickening agents”); Appeal Br. 37 (reciting in claim 45 that the dried residue recited in claim 25 “further compris[es] one or more thickening agents” (emphasis added)). We also note that the exemplary sensors relied on by the Appellant (Figures 1–3) merely comprise two different zwitterionic buffers (i.e., PIPES and MOPS)15 and two different enzymes (i.e., PQQ-GDH and FAD-GDH).16 Claim 25, however, generically recites “one or more zwitterionic buffers” and “one or more co-factors, co-enzymes, or a combination thereof.”17 Appeal Br. 35. In the 15 Spec. ¶¶ 78, 82. 16 Spec. ¶¶ 78, 82. 17 The Appellant discloses that FAD-GDH is a “co-enzyme.” Spec. ¶¶ 22, 24. The Appellant discloses that PQQ-GDH, on the other hand, is an “enzyme.” Spec. ¶ 23. Claim 25, however, limits the recited enzymes to “glucose dehydrogenases [GDHs], glucose oxidoreductases, and combinations thereof.” Appeal Br. 35. In that regard, the Appellant discloses: Enzymes useful for glucose analysis in electrochemical systems include oxidoreductases, such as glucose oxidases (GODs), glucose dehydrogenase (GDHs), which may also be referred to as glucose de- oxidoreductase (GlucDORs), and the like. Illustrative glucose dehydrogenases (GDHs) include, but are not limited to, wild-type GDHs, mutant GDHs, and the like. . . . It is to be understood that co- enzymes, such as GDH-NADs, FAD-GDHs, and the like, may be included in the reagent compositions described herein. Spec. ¶ 22 (emphasis added). The Appellant also discloses that flavin adenine dinucleotide (FAD) and pyrroloquinolinequinone (PQQ) are “bound cofactors.” Spec. ¶ 4. Thus, on this record, it is unclear whether PQQ-GDH is an enzyme, an Appeal 2021-004098 Application 16/289,933 11 absence of any evidence of a trend, we find that the Appellant’s evidence of unexpected results is not commensurate in scope with claim 25 for this additional reason. See In re Kollman, 595 F.2d 48, 56 (CCPA 1979) (in certain circumstances, “one having ordinary skill in the art may be able to ascertain a trend in the exemplified data which would allow him to reasonably extend the probative value thereof”). Finally, we recognize that sensors (A) have a faster time to maximum signal than sensors (B) and (C) in Appellant’s Figures 1–3. However, the Appellant does not direct us to any evidence establishing that the differences illustrated in Figures 1–3 would have been unexpected by one of ordinary skill in the art at the time of the Appellant’s invention. See In re Freeman, 474 F.2d 1318, 1324 (CCPA 1973) (explaining that the applicant must establish that the difference between the claimed invention and the prior art would not have been expected by one skilled in the art at the time of invention). Therefore, the Appellant’s arguments that the faster times exhibited by sensors (A) would have been “unexpected” are entitled to little weight. See De Blauwe, 736 F.2d at 705 (“It is well settled that unexpected results must be established by factual evidence. Mere argument or conclusory statements in the specification does not suffice.”). On balance, the evidence of record weighs in favor of the Examiner’s conclusion of obviousness. Therefore, the obviousness rejection of claims 25, 27, and 30–43 based on the combination of Nagakawa and Bhullar is sustained. enzyme containing a bound cofactor (PQQ), or a “co-enzyme” similar to FAD- GDH. Appeal 2021-004098 Application 16/289,933 12 b. Claims 44 and 45 Claim 44 depends from claim 25 and recites that the electrochemical sensor further comprises “one or more film forming agents.” Appeal Br. 36. Claim 45 depends from claim 25 and recites that the electrochemical sensor further comprises “one or more thickening agents.” Appeal Br. 37. The Examiner finds Bhullar teaches film formers and thickening agents. Final Act. 8–9. The Appellant does not direct us to any error in the Examiner’s findings. Rather, the Appellant argues that the Examiner does not explain why one of ordinary skill in the art would have added a film former and/or a thickening agent to Nagakawa’s modified sensor. Appeal Br. 30. The Examiner finds Bhullar discloses that a variety of adjuvants, including gelling agents, film formers and thickeners, will enhance the properties of a reagent. See Final Act. 11 (finding Bhullar teaches that “every adjuvant will enhance reagent properties”); Bhullar ¶ 162 (disclosing that it is “desirable for the [reagent] composition to include materials that specifically enhance the physical characteristics” of the reagent layer); Bhullar ¶ 163 (disclosing that adjuvants include gelling agents, thickeners, and film formers). Thus, for the same reason the Examiner concludes that it would have been obvious to add a gelling agent to Nagakawa’s dried reagent (i.e., to enhance the reagent properties), the Examiner concludes that it would have been obvious to one of ordinary skill in the art to add a thickener or a film former to Nagakawa’s modified dried reagent. See Final Act. 19–20. The Appellant also argues that adding a thickener or a film former in combination with a gelling agent would increase the viscosity of Nagakawa’s modified reagent and further slow dissolution, diffusion, and reaction time. Appeal Br. 31. Appeal 2021-004098 Application 16/289,933 13 As discussed above, Nagakawa contemplates using high viscosity materials in the disclosed sensor. Nagakawa ¶ 24. Moreover, Bhullar, like Nagakawa, is interested in faster analysis times and adds adjuvants, such as gelling agents, thickeners, and film formers, to the reagent composition. Bhullar ¶¶ 162–163. Thus, in the absence of any evidence to the contrary, we find that adding some amount of a thickener or a film former to Nagakawa’s modified dried reagent would not have been expected to significantly slow dissolution, diffusion, and reaction time whereby the objectives of Nagakawa’s invention cannot be achieved. See Schulze, 346 F.2d at 602 (“Argument in the brief does not take the place of evidence in the record.”). The obviousness rejection of claims 44 and 45 based on the combination of Nagakawa and Bhullar is sustained. 2. Rejections (2) and (3) The Appellant does not direct us to any error in the Examiner’s factual findings or legal conclusions in the rejections of claims 26, 28, and 29. Rather, the Appellant argues that Yamaoka and Inamori do not cure the “insufficiency of Nagakawa and Bhullar vis-à-vis claim 25.” Appeal Br. 32, 33. For the reasons discussed above, there is no deficiency in the obviousness rejection of claim 25 that requires curing by either Yamaoka or Inamori. Therefore, the obviousness rejections of claims 26, 28, and 29 are sustained. C. CONCLUSION The Examiner’s decision is affirmed. In summary: Appeal 2021-004098 Application 16/289,933 14 Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 25, 27, 30–45 103(a) Nagakawa, Bhullar 25, 27, 30–45 26, 28 103(a) Nagakawa, Bhullar, Yamoaka 26, 28 29 103(a) Nagakawa, Bhullar, Inamori 29 Overall Outcome 25–45 No time period for taking any subsequent action in connection with this appeal may be extended under 35 U.S.C. § 1.136(a)(1)(iv). AFFIRMED Copy with citationCopy as parenthetical citation