TRUSTEES OF TUFTS COLLEGE

Patent Trials and Appeals Board

Feb 24, 2022

2020006694 (P.T.A.B. Feb. 24, 2022)

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. 14/395,396 10/17/2014 Evangelia Bellas 166118.00643.T001828 7396 153544 7590 02/24/2022 Quarles & Brady LLP/Tufts University 411 E. Wisconsin Ave. Ste. 2400 Milwaukee, WI 53202-4428 EXAMINER BRANSON, DANIEL L ART UNIT PAPER NUMBER 1616 NOTIFICATION DATE DELIVERY MODE 02/24/2022 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): pat-dept@quarles.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE _________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD _________________ Ex parte EVANGELIA BELLAS, AMANDA BARYSHYAN, LINDSAY WRAY, and DAVID L. KAPLAN _________________ Appeal 2020-006694 Application 14/395,396 Technology Center 1600 _________________ Before RAE LYNN P. GUEST, DEBORAH KATZ, and TAWEN CHANG, Administrative Patent Judges. KATZ, Administrative Patent Judge. DECISION ON APPEAL Appellant1 seeks our review,2 under 35 U.S.C. § 134(a), of the Examiner’s decision to reject claims 1, 2, 7-9, 11, 12, 14-22, 69, and 71-73. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 We use the word “Appellant” as defined in 37 C.F.R. § 1.42. Appellant identifies the real party-in-interest as Trustees of Tufts College. (Appeal Br. 2.) 2 We consider the Final Office Action issued August 8, 2019 (“Final Act.”), the Appeal Brief filed April 9, 2020 (“Appeal Br.”), the Examiner’s Answer issued on July 24, 2020 (“Ans.”), the Reply Brief filed September 24, 2020 (“Reply Br.”) in reaching our decision. Appeal 2020-006694 Application 14/395,396 2 Appellant’s Specification is directed to compositions for skin and hair care that comprise non-hydrolyzed silk fibroin and a humectant. (Spec. ¶ 6.) The Specification reports that “the inventors discovered that the combination of a non-hydrolyzed silk fibroin solution and a humectant (e.g., a glycerin) can produce a composition with a gel-like consistency that is translucent and flowable, which is distinctly different from the brittle gel formed from the silk fibroin solution alone.” (Id. ¶¶ 7, 52.) Thus, the inventors assert that they discovered combining non-hydrolyzed silk fibroin solution with glycerin allows the gel to be flowable instead of brittle. Appellant’s claim 1 recites: A silk fibroin-based composition comprising a non- hydrolyzed silk fibroin solution and a humectant agent, wherein the non-hydrolyzed silk fibroin solution comprises non-hydrolyzed silk fibroin present in an amount of about 1% (w/v or w/w) to about 30 % (w/v or w/w); wherein the non-hydrolyzed silk fibroin solution and humectant agent are present in a volume ratio of about 1:2 to about 1:100; wherein the silk fibroin-based composition is flowable; and wherein at least 10% of the silk fibroin present in the fibroin-based composition is present in random coil configuration. (Appeal Br. 18.) Appellant’s claimed composition comprises two elements: non-hydrolyzed silk fibroin solution and humectant agent. The composition is limited only by the concentration of non-hydrolyzed silk fibroin in the solution and the ratio of non-hydrolyzed silk fibroin solution to humectant, which produces a flowable product with at least 10% silk fibroin present in random coil configuration. Appeal 2020-006694 Application 14/395,396 3 Pending claim 71 is also independent and recites similar limitations. (See Appeal Br. 21.) Appellant discusses the rejection of independent claim 71 separately from independent claim 1, but argues that Tsubouchi, Lu, and Jiang fail to render the claimed composition obvious for the same reasons argued against the rejection of claim 1. (See id. at 15-16.) Accordingly, we only refer to claim 1 in our analysis. See 37 C.F.R. § 41.37(c)(1)(iv). The Examiner rejected all of Appellant’s claims under 35 U.S.C. § 103(a) over Tsubouchi,3 Lu,4 and Jiang.5 (Final Act. 3-10.) Findings of Fact 1. Jiang teaches silk biomaterials for uses including as fillers for tissue space, templates for tissue reconstruction or regeneration, scaffolds for cells in tissue engineering applications and for disease models, surface coatings to improve medical device function, or platforms for drug delivery. (Jiang ¶ 2.) 2. Jiang teaches formulations of silk hydrogels comprising concentrated non-hydroylzed silk fibroin with glycerol added as a gelation enhancer. (See Jiang Abstract, ¶¶ 153-154, 221; see Ans. 5.) 3. Jiang teaches that an enhancer, such as glycerol, can be added to silk fibroin hydrogels at volumes of from 1 to 99% of the total volume and that the silk solution can be from 1 to 20% (w/v). (See Jiang ¶ 154.) 3 Tsubouchi et al., US Patent 7,901,668 B2, issued March 8, 2011. 4 Lu et al., “Insoluble and Flexible Silk Films Containing Glycerol,” BIOMACROMOLECULES, 11:143-50 (2010). 5 Jiang et al., US Patent Application Publication 2011/0111031 A1, published May 12, 2011. Appeal 2020-006694 Application 14/395,396 4 4. Jiang teaches that silk fibroin can have a protein structure with many different percentages of α-helix and random coil regions, including about 10% and higher α-helix and random coil formation. (See Jiang ¶ 97 (“In aspects of this embodiment, a biomaterial has a protein structure including, e.g., about 5% α-helix and random coil regions, about 10% α- helix and random coil regions, about 15% α-helix and random coil regions, about 20% α-helix and random coil regions, . . . or about 50% a-helix and random coil regions.”) 5. Tsubouchi teaches that aqueous solutions of silk protein composed mainly of amorphous silk fibroin provides “an emulsifier for cosmetic use which not only has an improved emulsifying power and feel during use, but wherein the emulsifier itself has a skin cell growth- promoting property.” (See Tsubouchi Abstract.) 6. Tsubouchi teaches that the emulsified materials described can be used in cosmetics, including cleansers, shampoos, rinses, creams, oils, waters, and other flowable products. (See Tsubouchi 5:6-22.) 7. Tsubouchi teaches silk protein compositions with a molecular weight of about 130,000, which the Examiner finds, and Appellant does not dispute, is non-hydrolyzed silk fibroin. (See Final Act. 4, citing Tsubouchi 12:40-45, 5:47-51; see Appeal Br. 4 (acknowledging that Tsubouchi teaches a composition comprising silk fibroin).) 8. Tsubouchi provides Experiment Example 1, which uses “silk gel” (also referred to as “silk protein aqueous gel”) with a silk protein concentration of 4.5%. (Tsubouchi 13:48-52; see Final Act. 5.) Appeal 2020-006694 Application 14/395,396 5 9. Experiment Example 1 of Tsubouchi provides for a composition that includes “silk gel” and glycerin. (Tsubouchi 13:48-52, 16:1-10, Table 1; see Final Act. 4.) 10. Experiment Example 1 of Tsubouchi uses 81.0 g “silk gel” and 2.8 g glycerin, a ratio of silk solution to humectant of 81.0:2.8. (Tsubouchi 13:48-52, 16:1-10, Table 1; see Final Act. 4.) 11. Appellant’s Specification discloses that glycerol6 is a humectant. (See Spec. ¶ 9; see Final Act. 4.) 12. Lu teaches preparation of silk films with glycerol to achieve optimal physical and mechanical characteristics, such as less brittleness and more flexibility. (See Lu 143.) 13. Lu teaches that the introduction of glycerol likely alters the hydrophobic hydration state of and therefore reduces silk secondary structural change from predominant random coils to α-helices. (See Lu 149, Figure 7.) 14. Lu teaches that silk films formed with increasing amounts of glycerol tend to have less molecules in beta-sheet formation and more molecules in alpha-helix formation. (See Lu 149; see Final Act. 6.) 15. Lu teaches purified silk fibroin solutions mixed with glycerol at weight ratios of 0, 5, 10, 20, 30, 40, and 50% (w/w). (See Lu 144; see Final Act. 6.) 6 Appellant acknowledges that glycerin and glycerol are synonymous. (See Appeal Br. 4.) Appeal 2020-006694 Application 14/395,396 6 Analysis We agree with the Examiner’s finding that Tsubouchi teaches a silk composition including glycerin (glycerol), wherein the silk comprises mainly non-hydrolyzed fibroin at a protein concentration of 4.5%. (See Final Act. 4; see FFs 5-11.) We also agree with the Examiner’s finding that Jiang teaches adding glycerol to silk solutions at 0-99% of the solution. (See Final Act. 6, 7; FF 3.) Thus, we agree with the Examiner that the claimed ratio of fibroin to humectant would have been obvious over Tsubouchi and Jiang, which suggest ratios of fibroin and humectant within or overlapping the ranges required by the claim. (See Final Act. 8.) The Examiner finds further that one of ordinary skill in the art would have understood that the amount of glycerol within the composition is a result effective variable that would have been routinely optimized until the desired properties of the end product were achieved, such as needing a certain gelation time or producing a less brittle product. (Final Act. 7-8.) This finding is supported by the teaching in Jiang that glycerol can be added to silk solutions as a gelation enhancer (see Jiang ¶¶ 153-154; see FF 2) and the teaching in Lu that “[t]he glycerol content in blend films [is] important for the control of silk secondary structural transitions and influencing the mechanical properties of the films” (Lu 149; see FFs 12-14). The Examiner reasons that claim limitations drawn to properties of the composition, for example the occurrence of random coil structure (see claims 1, 15, 16) would be inherent in the composition suggested by the combination of the prior art, absent evidence to the contrary. (See Final Act. 9, citing In re Best, 562 F.2d 1252, 1254 (CCPA 1977).) We agree with this reasoning and we agree with the Examiner’s conclusion that “the Appeal 2020-006694 Application 14/395,396 7 claimed invention would have been prima facie obvious to one of ordinary skill in the art at the time the invention was made because the prior art is suggestive of the claimed invention.” (Final Act. 10.) Appellant argues that paragraph 154 of Jiang, teaching that the amount of silk solution can range from about 1 w/v% to about 20 w/v%, refers to the concentration of silk fibroin within the solution, not to the amount of “non-hydrolyzed silk fibroin solution” as recited in claim 1. (See Appeal Br. 10.) We are not persuaded by this argument because paragraph 154 uses the phrase “concentration of silk solution,” without referring to the amount of silk fibroin in the solution. Furthermore, in the prior paragraph Jiang refers to the process of making a “silk solution,” not a process of making the fibroin within the solution. Specifically, Jiang states that silk fibroin hydrogels can be produced by preparing a solution comprising a silk fibroin, which corresponds to the “non-hydrolyzed silk fibroin solution” recited in claim 1, and mixing it with a solution comprising a gelation enhancer, which corresponds to the humectant recited in claim 1. (See Jiang ¶ 153.) Appellant does not direct us to a portion of Jiang that distinguishes the addition of enhancer to the silk fibroin solution from the addition of enhancer to the silk fibroin within the solution. Appellant argues that the Examiner misreads Jiang to find the ratio of non-hydrolyzed silk fibroin solution to humectant element of the claimed composition. (See Appeal Br. 7-11.) Appellant argues that [i]t would have been clear to one having ordinary skill in the art that Jiang is referring to the concentration of silk fibroin within the solution. It would be utterly nonsensical for Jiang to say that the gelatin enhancer can be 0-99% and that “either component may be added to a large excess of the other or in any relative Appeal 2020-006694 Application 14/395,396 8 concentration within the interval” (Jiang at ¶ [0154]), and then immediately limit the amount of the “other component” (i.e., the silk solution) to 1-20%. (Appeal Br. 10; see also Appeal Br. 14.) We are not persuaded by Appellant’s arguments. Jiang teaches that when glycerol is used as a gelation enhancer [t]he volume of added enhancer may vary from about 0% to about 99% of the total volume (i.e., either component may be added to a large excess of the other or in any relative concentration within the interval). The concentration of silk solution used can range from about 1% (w/v) to about 20% (w/v). (Jiang ¶ 154 (emphasis added).) The language of Jiang provides for gelation enhancer of any concentration up to 99% and silk solution of from about 1% to about 20%. Thus, Jiang provides for compositions with, for example, 15% silk fibroin solution and 30% glycerol (a 1:2 ratio as claimed), with 55% other ingredients. Appellant does not persuaded us that one of ordinary skill in the art would have understood Jiang to mean anything other than its plain language. Appellant argues further that because Jiang defines the range of gelation enhancer to include “practically all conceivable ratios,” Jiang does not teach that either the gelation enhancer or the silk fibroin solution is present in large excess. (Appeal Br. 10 (emphasis omitted).) According to Appellant, a prior art reference that identifies a nearly infinite range for a given parameter is not adequate as the basis for a prima facie obviousness rejection. (See id.) These arguments are also unpersuasive because the rejection is not based entirely on the concentration ranges taught in Jiang. In addition, the Examiner relies on the teachings that the amount of gelation Appeal 2020-006694 Application 14/395,396 9 enhancer is a result effective variable for gelation time and mechanical properties. Appellant’s argument that the teaching of Jiang is not an adequate basis for an obviousness rejection is unpersuasive because it fails to address the Examiner’s rejection in its entirety. Appellant argues that the motivation to combine put forth by the Examiner “exposes the absurdity of these rejections.” (Appeal Br. 11.) Appellant argues: The Examiner asserts that the amount of glycerol in the skin cream composition of Tsubouchi could have been optimized until the skin cream is “less brittle”, whatever that means in the context of a composition that is 0% brittle by nature of being a cream, or until a “certain decrease in the gelation time” is achieved, in the context of the Experiment Example 1 of Tsubouchi, where the silk fibroin is already in the form of a “silk gel” when it is introduced to the glycerol. (Id.; see also id. at 14.) Given that Appellant’s own Specification discusses the inventor’s reported discovery of combining a non-hydrolyzed silk fibroin solution and a humectant to “produce a composition with a gel-like consistency that is translucent and flowable, which is distinctly different from the brittle gel formed from the silk fibroin solution alone” to be used in a cream, we are not persuaded that the term “brittle” would have been foreign to those of ordinary skill in the art when describing silk fibroin gels for use in a cream. (Spec. ¶ 7; see also id. ¶ 32 (“The silk fibroin-based compositions and the emulsion compositions described herein can be formulated to any form desirable for a specific application. For example, the composition can be formulated to form a gel or hydrogel, a paste, a lotion, a cream . . . .”).) Similarly, Tsubouchi discusses a similarly known problem in that “although emulsified cosmetic materials obtained using protein-based Appeal 2020-006694 Application 14/395,396 10 emulsifiers generally have a soft, moist feel during use, it is often the case that when handled during actual use, they produce a crumbling feel and lack spreadability.” (Tsubouchi 2:42-46; see Ans. 7-8.) The Examiner’s rejection is not absurd - rather, it is supported by the facts of the record before us. Appellant disagrees that Lu teaches glycerol concentration is a result effective variable for determining properties of a silk fibroin-based composition as recited in claim 1. (See Appeal Br. 10-11.) Specifically, Appellant argues that the teaching in Lu that “glycerol plays different roles in silk films, depending on the processing methods and concentrations used and, therefore, resulting in distinguished film properties” directly contradicts its role as a result effective variable. (See id. at 11, quoting Lu 149.) Appellant argues further that Lu teaches using silk with glycerol only for silk films, not in creams, and that the results in creams would have been unpredictable. (See Appeal Br. 12; see also Reply Br. 5.) We are not persuaded by these arguments because even if specific roles played by glycerol can differ, Lu teaches that glycerol affects the secondary structural transitions between random coil, α-helix, and β-sheet in silk compositions. (See Lu 149.) The teaching supports the Examiner’s finding that Lu teaches glycerol is a result effective variable for the mechanical properties of silk compositions. (See Ans. 6.) Thus, one of ordinary skill in the art would have known that one could alter the mechanical properties by adjusting the amount of glycerol, regardless of the ultimate form of the silk composition. Appellant argues further that the prior art fails to teach or suggest the random coil configuration limitation of claim 1. (See Appeal Br. 11-13.) Appeal 2020-006694 Application 14/395,396 11 Appellant points to the teaching in Lu that the interaction between glycerol molecules and silk fibroin chains “likely altered the hydrophobic hydration state of protein chains because they are very hydrophobic proteins due to the high content of glycine-alanine repeats[] and, therefore, induced silk secondary structural change from predominant random coils (silk in solution or as cast) to α helices (Figure 7).” (Lu 149 (citation omitted).) Appellant argues that this statement in Lu teaches the exact opposite of what the Examiner asserts, wherein glycerol causes a change away from random coil structures. (See Appeal Br. 12.) Appellant argues further that the teaching in Lu of less beta-sheet content does not mean that fewer molecules have beta-sheet formation, but that the secondary structure of the molecules has less beta-sheet character. (See id.) Appellant’s arguments are not persuasive because claim 1 provides for a minimum absolute amount of random coil, “at least 10%,” rather than an amount relative to another composition, for example without humectant. Although Lu teaches that glycerol induces a change from predominant random coil to α helices, Appellant does not direct us to any teaching that such conversion will not result in “at least 10%” random coil, a concentration that we broadly interpret to encompass less than “predominant” random coil. “[A]t least 10% . . . random coil” can include secondary structure of the molecules with 80% or 90% of another form. Thus, in light of the breadth of claim 1, Appellant’s argument does not persuade us that the Examiner misinterprets the teachings of Lu or erred in finding that Lu teaches glycerol is a result effective variable to achieve desirable mechanical properties by controlling the structure of the silk fibroin. Furthermore, because Jiang presents a reason to include glycerol in Appeal 2020-006694 Application 14/395,396 12 a silk fibroin solution at ratios within the scope of Appellant’s claim 1, the resulting concentration of random coil configuration would be inherent. Appellant argues further that Jiang teaches silk fibroin material including β-turn and β-stranded regions and substantially free of α-helix and random coil regions. (See Appeal Br. 12-13, citing Jiang ¶¶ 96, 97.) This argument is not persuasive because, as Appellant acknowledges, Jiang also teaches that silk fibroin can include α-helix and random coil regions at about 10%, 15%, 20%, 25%, etc. up to about 50%. (See Appeal Br. 13, see Jiang ¶ 97.) Appellant does not provide support for the assertion that “the context of Jiang clearly supports that it would have been significantly less obvious to select the smallest possible number for the beta-turn and beta-strand regions and the largest possible number for the alpha-helix and random coil regions.” (Appeal Br. 13; see also Reply Brief 5-6.) Even if Jiang teaches a preference for one of these embodiments, which Appellant does not demonstrate, Jiang presents many other embodiments, each of which can be relied upon in an obviousness rejection. See In re Mills, 470 F.2d 649, 651 (CCPA 1972) (“All the disclosures in a reference must be evaluated, including nonpreferred embodiments, . . . and a reference is not limited to the disclosure of specific working examples.”). Appellant also argues that because Jiang expresses the protein structure of silk fibroin as a percentage of a combination of α-helix and random coil, it does not necessarily teach “at least 10% of the silk fibroin present in the fibroin-based composition is present in random coil configuration,” as required in claim 1. (See Appeal Brief 13; see Reply Br. 5-6.) To the contrary, because Lu teaches a range of glycerol concentration that encompasses the claimed range and teaches that the concentration of Appeal 2020-006694 Application 14/395,396 13 glycerol is a result effective variable to achieve desired mechanical properties by varying the mechanical structures of the silk fibroin, we are persuaded that it would have been obvious to one of ordinary skill to optimize the amount of glycerol in a silk fibroin-based composition to achieve the claimed concentration, which would inherently result in the claimed concentration of random coil. Appellant also argues that because Lu teaches a maximum weight ratio of silk fibroin to glycerol of 1:1, which is less than Appellant’s claimed range of about 1:2 to about 1:100, Lu cannot be relied upon for a teaching of a predominantly random coil formation. (See Reply Br. 3-4.) We are not persuaded by this argument, first because Jiang presents a reason to combine silk fibroin solution with glycerol within the range of ratios claimed, which would inherently produce the claimed range of random coil. In addition, Appellant’s claim 1 does not require “predominant” random coil formation, but only random coil configuration of “at least 10%,” which is contemplated in both Lu and Jiang. Appellant argues further that the Examiner’s reason to combine the references is inadequate. (See Appeal Br. 13-15.) Specifically, Appellant argues: The motivation to combine the prior art provided by the Office is flawed because the entirety of the motivation is related to the compositional context of the secondary references, Lu and Jiang, rather than the compositional context of the reference that is being modified, Tsubouchi. In other words, to the extent that the teaching of Lu and Jiang would have motivated one of ordinary skill in the art to modify silk fibroin compositions, they would have motivated them to modify insoluble silk films, as Lu discloses, or drug delivery platforms, as Jiang discloses, rather than the emulsifier for cosmetic use disclosed by Appeal 2020-006694 Application 14/395,396 14 Tsubouchi. The motivation to modify Tsubouchi or the motivation to combine Tsubouchi with other references needs to have a rational relationship to the teaching of Tsubouchi. In this case, there is no such relationship. (Appeal Br. 14.) Similarly, Appellant argues that the skilled artisan would have understood that the molecular environment of a film, as taught by Lu, is substantially distinct from a composition that is flowable, as claimed. (Reply Br. 5.) We are not persuaded by these arguments because both Tsubouchi and Lu are concerned with mechanical properties of silk fibroin, including the feel, such as crumbliness or brittleness. (See Tsubouchi 2:42-46 (noting that when handled during use, protein-based emulsifiers in cosmetic materials can have “a crumbling feel and lack [of] spreadability”); see Lu 143 (noting that “pure silk fibroin films tend to be stiff and brittle in the dry state over time, exhibiting impressive tensile strength but low elongation”).) In addition, Tsubouchi is concerned with silk fibroin gelation times, which Jiang teaches are enhanced with the addition of glycerol. (See Tsubouchi 9:28-31; see Jiang ¶ 154; see Ans. 13-14.) Thus, the Examiner provides a sufficient reason why one of ordinary skill in the art would have combined the teachings of the cited references, even if they refer to the ultimate use of silk fibroin in different forms. Appellant argues further that Tsubouchi does not rely on glycerol for gelation and so one of ordinary skill would not have looked to the teachings of Jiang for modifying gelation time. (See Appeal Br. 14-15.) Appellant cites to Example 4 of Tsubouchi, which states that gelation of the “silk gel” takes 2-4 days, but before glycerol is added. (See id., citing Tsubouchi 12:64-67.) Appellant argues that one of ordinary skill would not have Appeal 2020-006694 Application 14/395,396 15 necessarily wanted to change the gelation time taught in Tsubouchi. (See id.) This argument is not persuasive because even if Tsubouchi would not have provided a reason to include glycerol as a gelation agent, Jiang itself provides the reason and teaches compositions that include the ratio of silk solution to glycerol. (See Jiang ¶ 154.) We are persuaded that one of ordinary skill in the art desiring to optimize the gelation time of a silk fibroin-based composition would have known to add glycerol at different concentrations and ratios to silk fibroin solution from the teachings of Jiang. Appellant argues further that Tsubouchi solves the problem of crumbling and brittleness in silk fibroid solutions by presenting the composition of Table 1, which includes olive oil, jojoba oil, tocopherol, glycyrrhiza, and paraben, in addition to glycerin. (See Reply Br. 8.) According to Appellant, because this composition achieves a “non-brittle gel” there would have been no reason for one of ordinary skill in the art to add significantly more glycerin, such as that recited in claim 1. (See id.) This argument is unpersuasive because the Examiner cites other reasons to add increased glycerin, such as the increased gelation time taught in Jiang, and/or achieving a more flexible product as taught in Lu. In the Reply Brief, Appellant argues that the claimed formulations achieve unexpected results. (See Reply Br. 4-5.) Appellant does not raise an argument for patentability based on unexpected results in the Appeal Brief and does not provide good cause why these arguments could not have been raised. See 37 C.F.R. § 41.41(b)(2) (“Any argument raised in the reply brief which was not raised in the appeal brief, or is not responsive to an argument raised in the examiner’s answer, including any designated new Appeal 2020-006694 Application 14/395,396 16 ground of rejection, will not be considered by the Board for purposes of the present appeal, unless good cause is shown.”). Accordingly, we need not consider these arguments. Even if we consider them, though, the arguments are not persuasive. Appellant cites to the Specification to argue that a 1:1 ratio of glycerol to non-hydrolyzed silk fibroin was shown to be insufficient to achieve a flowable composition that maintains silk fibroin in a random coil configuration of at least 10%. (See Reply Br. 3-4, citing Spec. ¶ 7.) The portion of the Specification Appellant cites states: In one embodiment, the inventors discovered that the combination of a non-hydrolyzed silk fibroin solution and a humectant (e.g., a glycerin) can produce a composition with a gel-like consistency that is translucent and flowable, which is distinctly different from the brittle gel formed from the silk fibroin solution alone. In particular, when the volume ratio of glycerin to non-hydrolyzed silk fibroin solution is greater than 1:1 (e.g., about 2:1 to about 8:1), the interaction of glycerin and silk fibroin surprisingly provides a gel composition that is stable at room temperature for an extended period of time, e.g., at least about 12 months and does not form precipitation of the protein when sheared on the skin. (Spec. ¶ 7.) Given the teachings in Jiang of compositions that encompass the claimed ratios of glycerol to silk fibroin solution and the teaching that compositions with at least 10% random coil configuration can be achieved (see Jiang ¶¶ 97, 154), we are not persuaded that the characteristics Appellant asserts are not merely inherent. “The discovery of a new property or use of a previously known composition, even when that property and use are unobvious from the prior art, can not impart patentability to claims to the known composition.” In re Spada, 911 F.2d 705, 708 (Fed. Cir. 1990). See Appeal 2020-006694 Application 14/395,396 17 also In re Best, 562 F.2d 1252, 1255 (CCPA 1977) (“Where, as here, the claimed and prior art products are identical or substantially identical, or are produced by identical or substantially identical processes, the PTO can require an applicant to prove that the prior art products do not necessarily or inherently possess the characteristics of his claimed product. See In re Ludtke, supra [441 F.2d 660 (CCPA 1971)]. Whether the rejection is based on ‘inherency’ under 35 U.S.C. 102, on “prima facie obviousness” under 35 U.S.C. 103, jointly or alternatively, the burden of proof is the same, and its fairness is evidenced by the PTO’s inability to manufacture products or to obtain and compare prior art products.”) We note, too, that although Appellant distinguishes the translucent, flowable gel-like consistency of non-hydrolyzed silk fibroin combined with a humectant from the brittleness of a gel formed from the silk fibroin solution alone (see Reply Br. 3-4, citing Spec. ¶ 7), Lu teaches that blended films comprising silk fibroin solution and glycerol “either in the dry or wet state, were more ductile than methanol-treated and water-annealed pure silk fibroin films, while offering some control of ultimate and yield strength properties” (Lu 149). As discussed above, Lu teaches that glycerol is a result effective variable for the mechanical properties of silk fibroin. Appellant does not explain why the effect of glycerol on silk fibroin described in the Specification would have been unexpected in light of the teachings of Lu. Similarly, Appellant argues that a product referred to as “ALLSilk™ gel technology” demonstrates unexpected results as well. (See Reply Br. 3- Appeal 2020-006694 Application 14/395,396 18 4.) In support, Appellant points to paragraph 2267 of the Specification, which states: the mechanism of the ALLSilk™ gel technology is distinctly different from other mechanisms of silk gelation, which primarily involve β-sheet formation. In contrast, the ALLSilk™ technology exhibits silk gelation without or with minimal β- sheet formation and maintains dominant random-coil content. Without wishing to be bound by theory, the difference in the silk fibroin conformation (random-coil vs. beta-sheet) determined in the ALLSilk™ gel and expired gel likely contribute, in part, to the flow-ability of the ALLSilk™ gel. (Spec. ¶ 226.) These characteristics of the product of ALLSilk™ gel technology do not persuade us that a composition within the scope of Appellant’s claim 1 would have been unexpected because claim 1 requires only that “at least 10% of the silk fibroin present in the fibroin-based composition is present in random coil configuration.” (Appeal Br. 18.) Appellant does not explain why ALLSilk™ gel technology is commensurate with the scope of claim 1. See In re Kao, 639 F.3d 1057, 1068 (Fed. Cir. 2011) (“Evidence of secondary considerations must be reasonably commensurate with the scope of the claims.”). None of Appellant’s arguments persuade us that the composition of claim 1 would not have been obvious over the prior art cited by the Examiner. Accordingly, Appellant fails to persuade us that the Examiner erred in rejecting claim 1. 7 Appellant cites paragraph 300 of the Specification, but we find the quoted text in paragraph 226. Appeal 2020-006694 Application 14/395,396 19 Appellant relies on the same arguments regarding the rejection of claim 71 and does not address any of the rejected dependent claims. (See Appeal Br. 15-16.) Accordingly, we are not persuaded that the Examiner erred in rejecting these claims. Conclusion Upon consideration of the record and for the reasons given, we affirm the Examiner’s rejection. In summary: Claim(s) Rejected 35 U.S.C. § References/Basis Affirmed Reversed 1, 2, 7-9, 11, 12, 14-22, 69, 71-73 103 Tsubouchi, Lu, Jiang 1, 2, 7-9, 11, 12, 14-22, 69, 71-73 No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136. See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED