Ex Parte BonnyDownload PDFPatent Trial and Appeal BoardOct 11, 201813141314 (P.T.A.B. Oct. 11, 2018) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 13/141,314 11/14/2011 20999 7590 10/15/2018 HAUG PARTNERS LLP 745 FIFTH A VENUE - 10th FLOOR NEW YORK, NY 10151 FIRST NAMED INVENTOR Christophe Bonny 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. A385-14 4298 EXAMINER NIEBAUER, RONALD T ART UNIT PAPER NUMBER 1658 NOTIFICATION DATE DELIVERY MODE 10/15/2018 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@haugpartners.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte CHRISTOPHE BONNY Appeal2017-004466 1 Application 13/141,314 Technology Center 1600 Before FRANCISCO C. PRATS, JEFFREYN. FREDMAN, and DEBORAH KATZ, Administrative Patent Judges. PRATS, Administrative Patent Judge. DECISION ON APPEAL This appeal under 35 U.S.C. § 134(a) involves a claim to a polypeptide transporter construct composed of a combination of D-amino acids and L-amino acids. The Examiner rejected the claim for obviousness. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. STATEMENT OF THE CASE Appellant's invention involves a polypeptide construct that can be conjugated to a variety of cargo moieties, such as proteins, peptides, nucleic acids, cytotoxic agents, and organic molecules. Spec. 1. Conjugation to 1 Appellant states that the real party in interest in this appeal is Xigen Inflammation, Ltd. Br. 1. Appeal2017-004466 Application 13/141,314 Appellant's polypeptide construct allows the cargo moiety to be transported "into an organism, a tissue, a cell ( e.g. to be treated), a cellular subcompartiment [sic] and/or into the nucleus of a cell." Id. at 9. The Specification discloses that polypeptides capable of traversing cell membranes include "[t]ranslocatory proteins [which] are considered as a group of peptides capable of effecting transport of macromolecules between cells (translocatory proteins), such as HIV-I TAT (HIV) .... " Id. at 5. Appellant's invention is directed to the finding that configuring a transport polypeptide, such as the HIV TAT protein, to have a particular combination of D- and L-amino acids is advantageous in achieving optimal duration of action of the cargo moiety within the target cell: This inventive D-/L-pattem allows a skilled person to define the in vivo or in vitro persistence of the inventive novel transporter construct as defined above in the cell precisely enough as a time sufficiently long to ensure administration and entering of the inventive novel transporter construct into the cell or nucleus prior to degradation of the inventive novel transporter construct by proteases within a considerable time limit. This in vivo or in vitro persistence of the inventive novel transporter construct in the cell is in fact dependent on the specific content and position of the D-amino acids in alteration with the specific content of L-amino acids as defined in generic formula (I). Id. at 9; see also id. at 8 (showing generic formula (I) of Appellant's transporter polypeptide). The Specification discloses: As surprisingly found by the inventor[], such advantageous properties may be conferred to a trafficking sequence, particularly to any trafficking sequence known in the art only by the inventive pattern (herein also described as D-/L- pattem) of the above defined generic formula (I), the specific content and position of the D-amino acids in alteration with the 2 Appeal2017-004466 Application 13/141,314 specific content of L-amino acids as defined in generic formula (I). Id. at 9. More specifically, the Specification discloses that TAT transport protein sequences, modified to have a combination of D- and L-amino acids in accordance with generic formula (I), have a reduced proteolytic resistance to human serum as compared to a TAT transport protein having all D-amino acids, but have an increased proteolytic resistance to human serum as compared to a TAT transport protein having all L-amino acids. Id. at 93, 101; see also Appellant's Figure 3. Claim 1, the sole claim on appeal, reads as follows: 1. A transporter construct comprising a sequence selected from the group consisting of an amino acid sequence comprising rKKRrQRRr (SEQ ID N0:20) and an amino acid sequence comprising rRRQrRKKr (SEQ ID N0:21 ), wherein lowercase designations indicate D-amino acids and uppercase designations indicate L-amino acids. Br. A-1 (Claims App 'x). The sole rejection before us for review is the Examiner's rejection of claim 1, under 35 U.S.C. § I03(a), for obviousness over Hotchkiss. 2 Ans. 2- 3. OBVIOUSNESS The Examiner's Prima Facie Case The Examiner cited Hotchkiss as disclosing membrane-permeant peptides, including "a preferred embodiment of a peptide comprising RKKRRQRRR (SEQ ID N0:7) and specifically recit[ing] RKKRRQRRR (section 0082)," the same sequence as SEQ ID NO: 20 recited in Appellants' 2 US 2006/0166881 Al (published Jul. 27, 2006). 3 Appeal2017-004466 Application 13/141,314 claim 1, except for the specific pattern of D- and L-amino acids recited in the claim. Ans. 2. As to the requirement in Appellants' claim 1 for SEQ ID NO: 20 to be composed of a specific pattern of D- and L-amino acids, the Examiner found that Hotchkiss "expressly teach[ es that] incorporating D-amino acids is particularly useful when stability is desired (section 0085) and suggest[s] combinations of D and L-amino acids for the peptides (sections 0071 and 0085)." Id. The Examiner reasoned that, because Hotchkiss "teach[ es] (page 8 section 0082 and example 1) a preferred embodiment of a peptide comprising RKKRRQRRR (SEQ ID N0:7) one would be motivated to use such compound as a starting point." Id. Moreover, the Examiner reasoned, because Hotchkiss "expressly teach[ es] incorporating D-amino acids is particularly useful when stability is desired ( section 0085) and suggest[ s] combinations of D- and L-amino acids for the peptides (section 0071 and 0085) one would be motivated to incorporate D-amino acids with a reasonable expectation of success." Id. at 2-3. Accordingly, the Examiner reasoned, an ordinary artisan would have been motivated to "make a peptide comprising instant SEQ ID N0:20 thus meeting the limitations as recited in instant claim 1. It is noted that the D and L amino acids are of the same chemical composition ( compare MPEP 2144.09)." Id. In particular, the Examiner noted, "[i]n the instant case, there are a finite number of positions to use either the Dor L-amino acid." Id. 4 Appeal2017-004466 Application 13/141,314 Analysis As stated in In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992): [T]he examiner bears the initial burden ... of presenting a primafacie case ofunpatentability .... After evidence or argument is submitted by the applicant in response, patentability is determined on the totality of the record, by a preponderance of evidence with due consideration to persuasiveness of argument. In the instant case, having considered all of the evidence and arguments presented by Appellant and the Examiner, Appellant does not persuade us that the preponderance of the evidence fails to support the Examiner's conclusion of obviousness as to claim 1. Hotchkiss discloses "compositions for drug delivery by the use of novel cell membrane-permeant peptide conjugate coordination and covalent compounds having target cell specificity." Hotchkiss ,r 3. Hotchkiss discloses that its drug delivery compositions are composed of three components: 1) a cell membrane-permeant peptide sequence made up of D- amino acids, L-amino acids or a combination of D- and L- amino acids; 2) a functional or non-functional linker motif; and 3) a chelator moiety able to coordinate metals useful in medical imaging and therapy (FIG. 1 ), or other cargo molecule such as a diagnostic substance or pharmaceutically active agent. Id. ,r 71 ( emphasis added). Hotchkiss discloses that a preferred membrane permeant peptide component of its compositions has the same sequence of amino acids as in SEQ ID NO: 20 recited in Appellant's claim 1: A preferred embodiment comprises Tat protein residues 48-57 (GRKKRRQRRR) (SEQ ID NO: 7). Residue number may be selected or modified to achieve a desired level of cellular 5 Appeal2017-004466 Application 13/141,314 uptake as there is a correlation between decreased length of at least some permeation peptides and decrease cellular uptake of the conjugate. For example, to generate the sequences identified as 13a, 14a, 15, 16, 17 of Table 2, one additional amino acid was removed from the N-terminus of the longest Tat basic domain sequence (RKKRRQRRR) while all other aspects of the peptide remained the same. Id. ,I 82. Hotchkiss' s preferred construct, thus, differs from the construct recited in Appellant's claim 1 only in that Hotchkiss's membrane permeant peptide is not composed of the specific pattern of D- and L-amino acids recited in Appellant's claim 1. As noted above, however, Hotchkiss expressly discloses that its membrane permeant peptide may be made up of "a combination of D- and L-amino acids." Id. ,r 71. Hotchkiss explains that the "incorporation of non-natural amino acids, including synthetic non-native amino acids, substituted amino acids, or one or more D-amino acids into the peptides ( or other components of the complexes) of the present invention (subsequently referred to herein as 'D- peptides') is advantageous in a number of different ways." Id. ,r 85 ( emphasis added). Hotchkiss describes a number of advantages of incorporating D-amino acids into the membrane permeant peptide component of its constructs: D-amino acid-containing peptides exhibit increased stability in vitro or in vivo compared to L-amino acid-containing counterparts. Thus, the construction of peptides incorporating D-amino acids can be particularly useful when greater intracellular stability is desired or required. More specifically, D-peptides are resistant to endogenous peptidases and proteases, thereby providing better oral transepithelial and transdermal delivery of linked drugs and conjugates, improved 6 Appeal2017-004466 Application 13/141,314 bioavailability of membrane-permeant complexes, and prolonged intravascular and interstitial lifetimes when such properties are desirable. The use of D-peptides can also enhance transdermal and oral transepithelial delivery of linked drugs and other cargo molecules. As shown in Example 14, the use of D-amino acids in the membrane permeant peptide greatly increases the accumulation of linked drugs or other cargo molecules into cells. Additionally, D-peptides cannot be processed efficiently for major histocompatibility complex class II-restricted presentation to T helper cells, and are therefore less likely to induce humoral immune responses in the whole organism. Id. ,I 85. Hotchkiss discloses that, although inclusion of D-amino acids into its constructs imparts desirable properties, it is also desirable to include L-amino acids in its constructs in certain circumstances: Id. On the other hand, when it is more desirable to allow the peptide to remain active for only a short period of time, the use of L-amino acids in the peptide can allow endogenous peptidases in a cell to digest the peptide in vivo, thereby limiting the cell's exposure to the membrane-permeant peptide covalent and coordination complexes comprising the peptides disclosed herein. As to the inclusion of combinations of D- and L-amino acids in its constructs, Hotchkiss discloses: It will be apparent that it is possible to construct complexes in which different portions contain either D- or L-amino acids. For example and without limitation, it is possible to construct a complex in which a cell permeant peptide and a metal chelator comprised of D-amino acids are connected by a functional linker comprised of L-amino acids. Other such combinations be readily apparent to those of ordinary skill in the art and are within the scope of the present invention. 7 Appeal2017-004466 Application 13/141,314 Id. ( emphasis added) Given the teachings of Hotchkiss, we agree with the Examiner that an ordinary artisan would have considered the construct recited in Appellant's claim 1 prima facie obvious. As seen above, Hotchkiss's preferred membrane permeant peptide differs from the 9 amino acid polypeptide of SEQ ID NO: 20 recited in Appellant's claim 1 only in that Hotchkiss's peptide is not composed of the specific combination of D- and L-amino acids recited in claim 1. See Hotchkiss ,r 82. As the Examiner pointed out, however, Hotchkiss states expressly that its membrane permeant peptide may be composed of a combination of D- and L-amino acids. Id. ,r 71. As seen above, Hotchkiss' s preferred membrane permeant peptide sequence has only 9 amino acids, or at most 10 amino acids, each of which may be either a D- or L-amino acid. See id. ,r 82. Accordingly, because Hotchkiss's preferred membrane permeant peptide sequence has at most 10 amino acids, and because only two possible options were available at each position, we agree with the Examiner's finding that, when following Hotchkiss' s express teaching to prepare a variant of its membrane permeant peptide composed of a combination of D- and L-amino acids, an ordinary artisan was presented with a finite number of options. Moreover, because Hotchkiss states expressly that its membrane permeant peptide may be composed of a combination of D- and L-amino acids, and because the construct recited in Appellant's claim 1 is one species of the finite set of possible combinations of D- and L-amino acids for Hotchkiss' s preferred membrane permeant peptide, we discern no error in 8 Appeal2017-004466 Application 13/141,314 the Examiner's conclusion that the construct recited in Appellant's claim 1 would have been prima facie obvious to an ordinary artisan, particularly in light of Hotchkiss' s teachings (Hotchkiss ,r 85) regarding the advantages of using one or more D-amino acids in combination with L-amino acids. See Merck & Co. v. Biocraft Labs., Inc., 874 F.2d 804, 807 (Fed. Cir. 1989) (species claim held obvious where it recited one of 1200 possible combinations of embodiments disclosed by reference and where reference suggested no preference for claimed embodiment); see also id. at 808 (That a reference "discloses a multitude of effective combinations does not render any particular formulation less obvious."). We acknowledge, but are unpersuaded by, Appellant's argument that "Hotchkiss fails to provide any specific direction or guidance as to which amino acid residues, if any, should be placed in the D configuration and which amino acid residues, if any, should be placed in the L-configuration of all of the cell membrane-permeant peptides disclosed." Br. 4--5; see also id. at 6 ("While Hotchkiss may disclose an amino acid sequence that has the same residues as the amino acid sequence of SEQ ID N0:20 in the present application (see ,r 0082), Hotchkiss does not provide the precise arrangement of D- and L- residues of the sequence."). That Hotchkiss does not expressly disclose the precise arrangement of D- and L-amino acids recited in Appellant's claim 1 does not demonstrate that the construct recited in claim 1 would have been unobvious. See Dann v. Johnston, 425 U.S. 219,230 (1976) ("[T]he mere existence of differences between the prior art and an invention does not establish the invention's nonobviousness. "). 9 Appeal2017-004466 Application 13/141,314 Moreover, as discussed above, Hotchkiss's preferred membrane permeant peptide sequence has at most 10 amino acids, and may be composed of as few as 9 amino acids. See Hotchkiss ,r 82. Only two possible options were available at each position, either a D- or L-amino acid. Thus, when following Hotchkiss' s express teaching to prepare a variant of its membrane permeant peptide composed of a combination of D- and L- amino acids (see id. ,r 71 ), an ordinary artisan was presented with a finite number of possible combinations of D- and L-amino acids with respect to Hotchkiss' s preferred membrane permeant peptide. As also discussed above, and is undisputed on this record, the construct recited in Appellant's claim 1 is one species of the finite set of possible combinations of D- and L-amino acids for Hotchkiss' s preferred membrane permeant peptide. Thus, rather than using hindsight to arrive at the construct recited in Appellant's claim 1 based on the teachings in Hotchkiss, an ordinary artisan need only have selected from the finite set of possible combinations of D- and L-amino acids from which Hotchkiss' s preferred membrane permeant peptide could be assembled. Because arriving at the construct of claim 1 from the teachings of Hotchkiss only required selecting from a finite set of suitable options, Appellant does not persuade us that Hotchkiss failed to provide adequate guidance for preparing Appellant's claimed construct. We acknowledge Hotchkiss' s express disclosure of membrane permeant peptides composed of only D-amino acids (see Hotchkiss ,r 83), as well as the disclosure in Table 2 of Hotchkiss, in which only two of the membrane permeant peptides, constructs 9i and 1 lk, included a mixture of D- and L-amino acids (id. ,r 231 (Table 2)). We are not persuaded, however, 10 Appeal2017-004466 Application 13/141,314 that Hotchkiss teaches away from the construct recited in Appellant's claim I. See Br. 7. Specifically, contrary to Appellant's contention that Hotchkiss suggests membrane permeant peptides composed of only D-amino acids, Hotchkiss states expressly that its constructs may include "a cell membrane- permeant peptide sequence made up of D-amino acids, L-amino acids or a combination of D- and L-amino acids." Hotchkiss ,r 71 ( emphasis added). Hotchkiss, moreover, discloses that its membrane permeant peptides may include as few as one D-amino acid, or a simple majority of D-amino acids. See id. ,r 83 ("In one preferred embodiment any of the aforementioned membrane peptides may contain at least one D-amino acid. In another preferred embodiment, a majority of the amino acid residues in any of the aforementioned peptides can comprise D-amino acids."). Appellant does not persuade us, therefore, that Hotchkiss teaches away from the construct in claim 1 on appeal, which recites a construct composed of three D-amino acids and six L-amino acids. See Br. A-1 (Claims App'x). We acknowledge, as Appellant contends (see Br. 7), that "patents are not barred just because it was obvious 'to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it."' Procter & Gamble Co. v. Teva Pharmaceuticals USA, Inc., 566 F.3d 989, 997 (Fed. Cir. 2009) (quoting In re O'Farrell, 853 F.2d 894,903 (Fed. Cir. 1988)). In the present case, however, rather than providing only general guidance, Hotchkiss expressly identifies the amino acid sequence recited in Appellant's claim 1 as being the sequence of a preferred membrane 11 Appeal2017-004466 Application 13/141,314 permeant peptide (Hotchkiss ,r 82), and teaches that substituting D-amino acids for one or more of the amino acids in any of the peptides in its constructs provides advantages as to therapeutic properties of the resulting construct (see id. ,r,r 83, 85). Thus, rather than providing only general guidance, Hotchkiss identifies a specific 9 amino acid transport peptide, and teaches that any number of the amino acids in that peptide can be either a D- or L-amino acid, thereby providing a limited and finite set of options from which to choose, to impart to the preferred transport peptide the therapeutic advantages taught in the reference. We acknowledge, but are unpersuaded by, Appellant's contention that the construct recited in claim 1 has properties that an ordinary artisan would have considered to be unexpected. See Br. 6-8. In particular, we acknowledge the data in Appellant's Figure 3, which shows that, when treated in either 10% or 50% human serum, TAT peptides corresponding to the sequences in Appellant's claim 1 were essentially undigested for the 28 day treatment period when formed of all D-amino acids, but were entirely digested after 72 hours by the proteases in the serum when formed of all L- amino acids. See Appellant's Figure 3. We acknowledge, as also seen in Appellant's Figure 3, that the TAT peptides having the specific combination of D- and L-amino acids recited in Appellant's claim 1 were digested more slowly than the corresponding peptides formed entirely of L-amino acids, and also that the D- and L-amino acid combination peptides were ultimately digested by the proteases in the serum, unlike the peptides formed entirely of D-amino acids. See id. We further acknowledge Appellant's Specification characterizing these results as "show[ing] a degradation within a suitable time limit, 12 Appeal2017-004466 Application 13/141,314 allowing to limit the in vivo stability for therapeutic applications." Spec 101. We agree with the Examiner, however, that these results would have been expected in view of Hotchkiss. See Ans. 5. Specifically, as noted above, Hotchkiss discloses that "D-amino acid- containing peptides exhibit increased stability in vitro or in vivo compared to L-amino acid-containing counterparts" whereas "[ o ]n the other hand ... the use of L-amino acids in the peptide can allow endogenous peptidases in a cell to digest the peptide in vivo, thereby limiting the cell's exposure to the membrane-permeant peptide covalent and coordination complexes comprising the peptides disclosed herein." Hotchkiss ,r 85. Based on these properties, Hotchkiss explains the desirability of preparing constructs composed of combinations of D- and L-amino acids in its constructs: It will be apparent that it is possible to construct complexes in which different portions contain either D- or L-amino acids. For example and without limitation, it is possible to construct a complex in which a cell permeant peptide and a metal chelator comprised of D-amino acids are connected by a functional linker comprised of L-amino acids. Other such combinations be readily apparent to those of ordinary skill in the art and are within the scope of the present invention. Id. ( emphasis added). Given Hotchkiss' disclosures that incorporating D-amino acids imparts protease resistance to the transport protein constructs, and incorporating L-amino acids allows protease digestion of the constructs, we agree with the Examiner that an ordinary artisan would not have considered it unexpected that constructs composed of combinations of D- and L-amino 13 Appeal2017-004466 Application 13/141,314 acids as taught by Hotchkiss would have a protease resistance somewhere between the construct composed of all D- or all L-amino acids. It is well settled, moreover, that "when unexpected results are used as evidence of nonobviousness, the 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). In the present case, as noted above, the comparison advanced by Appellant to show unexpected results is between the claimed constructs and constructs composed of either all D-amino acids, or all L-amino acids. See Appellant's Fig. 3. As also noted above, and as Appellant concedes (see Br. 5), Hotchkiss discloses two constructs having a combination of D- and L- amino acids, constructs 9i and 1 lk (see Hotchkiss ,r 231 (Table 2)). Because Appellant did not compare the claimed constructs to the prior art constructs having combinations of D- and L-amino acids, we are not persuaded that Appellant compared the claimed constructs to the closest prior art. In sum, for the reasons discussed, Appellant does not persuade us that Hotchkiss fails to suggest preparing the construct recited in Appellant's claim 1. Also, for the reasons discussed, Appellant does not persuade us that the objective evidence of nonobviousness in relation to unexpected results is sufficient to outweigh the prior art evidence of obviousness. Accordingly, weighing the evidence of record as a whole, we find that the preponderance of the evidence supports the Examiner's conclusion of obviousness as to claim 1. We, therefore, affirm the Examiner's rejection of claim 1 over Hotchkiss. 14 Appeal2017-004466 Application 13/141,314 SUMMARY For the reasons discussed, we affirm the Examiner's rejection of the Examiner's rejection of claim 1, under 35 U.S.C. § 103(a), for obviousness over Hotchkiss. TIME PERIOD 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 15 Copy with citationCopy as parenthetical citation