Ex Parte Hyde et alDownload PDFPatent Trial and Appeal BoardJun 12, 201812228892 (P.T.A.B. Jun. 12, 2018) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE FIRST NAMED INVENTOR 12/228,892 08/13/2008 Roderick A. Hyde 39124 7590 06/14/2018 CAROL NOTTENBURG 264 SENECA PLACE NW RENTON, WA 98057 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. AJE203 6539 EXAMINER SZPERKA, MICHAEL EDWARD ART UNIT PAPER NUMBER 1644 NOTIFICATION DATE DELIVERY MODE 06/14/2018 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): carol.nottenburg@cougarlaw.com chris. pratt@cougarlaw.com cnot@comcast.net PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte RODERICK A. HYDE, MURIEL Y. ISHIKAWA, EDWARD K.Y. JUNG, WILLIAM GATES, ALOIS A. LANGER, ERIC C. LEUTHARDT, ROYCE A. LEVIEN, MARK A. MALAMUD, CLARENCE T. TEGREENE, THOMAS A. WEA VER, CHARLES WHITMER, LOWELL L. WOOD JR., and VICTORIA Y.H. WOOD 1 Appeal2017-005763 Application 12/228,892 Technology Center 1600 Before JEFFREY N. FREDMAN, ULRIKE W. JENKS, and JOHN G. NEW, Administrative Patent Judges. NEW, Administrative Patent Judge. DECISION ON APPEAL 1 Appellants identify Deep Science LLC as the real party-in-interest. App. Br. 4. Appeal2017-005763 Application 12/228,892 SUMMARY Appellants file this appeal under 35 U.S.C. § 134(a) from the Examiner's Final Rejection of claims 1-5. Specifically, claims 1--4 stand rejected as unpatentable under 35 U.S.C. § 103(a) as being obvious over the combination of Coller (US 5,328,840, July 12, 1994) ("Coller") and Pallenberg et al. (US 2007 /0059316 A 1, March 15, 2007) ("Pallenberg"). Claims 1--4 also stand rejected as unpatentable under 35 U.S.C. § 103(a) as being obvious over the combination of Pallenberg and N. Hamdy et al., Sheep Red Blood Cells Armed with Anti-CD20 Single-Chain Variable Fragments (ScFvs) Fused to a Glycosylphosphatidylinositol (GP!) Anchor: A Strategy to Target CD20-Positive Tumor Cells, 297 J. IMMUNOL. METHODS, 109-124 (2005) ("Hamdy"). 2 Appeal2017-005763 Application 12/228,892 Claims 1-5 stand rejected as unpatentable under 35 U.S.C. § 103(a) as being obvious over the combination of Coller, Pallenberg, and Wilson et al. (WO 2005/034997 A2, April 21, 2005) ("Wilson"). 2, 3 We have jurisdiction under 35 U.S.C. § 6(b ). We AFFIRM. NATURE OF THE CLAIMED INVENTION Appellants' invention is directed to compositions and methods of using modified red blood cells, including a target-binding agent bound to the cells, for targeted delivery of imaging agents, drugs, and peptide and protein pharmaceuticals. Abstract. 2 The Examiner also rejected claims 1-5 as unpatentable under the judicially-created doctrine of nonstatutory obviousness-type double patenting over: (1) claims 1-24 of Hyde et al. (US 8,211,656 B2, July 3, 2012) ("Hyde") and "Kaplan et al." (but see fn.3, infra); (2) claims 1-24 of Hyde in view of Wilson et al. (WO 2005/034997 A2) and "Kaplan et al."; and (3) further provisionally rejected claims 1-5 on the same ground over claims 1-16 of Appellants' copending Application No. 12/228,893, as evidenced by Pallenberg. Final Act. 14--16. The Examiner has withdrawn the latter provisional rejection because Appellants' copending application has been abandoned. Ans. 13. Appellants do not argue or otherwise mention the other obviousness-type double patenting rejections in their Appeal Brief. We consequently summarily affirm the Examiner's rejections on this ground. See 37 C.F.R. § 4I.37(c)(iv) ("[A]ny arguments or authorities not included in the appeal brief will be refused consideration by the Board for purposes of the present appeal"). 3 We are unable to locate any prior art reference by "Kaplan et al." in the record on appeal. However, because Appellants do not argue the rejections citing this prior art, the actual identity of the "Kaplan et al." reference is immaterial. 3 Appeal2017-005763 Application 12/228,892 REPRESENTATIVE CLAIM Claim 1 is representative of the claims on appeal and recites: 1. A pharmaceutical composition, comprising: a red blood cell including at least one target-binding agent including a target recognition moiety coupled to a photoactivatable molecule and a quencher molecule, wherein the at least one target-binding agent is configured to emit at least one singlet oxygen radical molecule upon exposure to electromagnetic radiation of a suitable wavelength when the at least one target-binding agent is bound to a target molecule; and a pharmaceutically acceptable excipient. App. Br. 26. ISSUES AND ANALYSES We agree with, and adopt, the Examiner's findings and conclusion that the appealed claims are obvious over the combined cited prior art. We address the arguments raised by Appellants below. A. Rejection of claims 1--4 over Coller and Pallenberg Issue 1 Appellants argue that the Examiner erred because the Examiner failed to set forth a rational underpinning explain why a person of ordinary skill in the art would have been motivated to combine the teachings of Coller and Pallenberg. App. Br. 14. Analysis The Examiner finds Coller teaches methods of administering erythrocytes which are targeted to desired locations in vivo; and that such targeting molecules comprise one or more peptides, proteins, antibodies, 4 Appeal2017-005763 Application 12/228,892 lectins, carbohydrates, and steroids. Final Act. 3 (citing Coller, e.g., cols. 9, 18). The Examiner finds Coller particularly teaches the use of antibodies comprising single chain variable domains ("scFvs"). Id. ( citing Coller col. 19). The Examiner points out that that scFvs are disclosed as "target binding agents" in Examples 1-3 of Appellants' Specification. Id. at 4. The Examiner further finds that Coller teaches that the targeted erythrocytes can be loaded with a variety of diagnostic imaging reagents, including contrast agents and radionuclides, as well as therapeutic agents such as chemotherapeutics and thrombolytic agents. Id. ( citing Coller col. 17). The Examiner finds, however, that Coller does not teach that the targeting molecules bound to red blood cells are conjugated to a photosensitizer and a quencher molecule. Id. The Examiner finds Pallenberg teaches therapeutic and diagnostic methods involving photodynamic therapy, which is efficacious for the treatment of tumors although it can often damage non-target cells. Ans. 3 (citing Pallenberg Abstr., ,r,r 6, 7, 11, claims 1-64). The Examiner finds that Pallenberg teaches that an advantage of its methods and compositions is that its compositions are inactive, and hence non-toxic, until bound to the desired target and irradiated with light ( electromagnetic radiation) of the appropriate wavelength to release singlet oxygen radicals. Id. ( citing Pallenberg ,r,r 5---6, Fig. 1). Specifically, the Examiner finds that Pallenberg expressly teaches that its compositions comprise a donor, such as a fluorophore, photosensitizer or other such agent, linked to a targeting moiety and to an acceptor moiety, such as a quenching agent, in such a way that activation of the donor, such as the fluorophore or the photosensitizer, is quenched unless and until the 5 Appeal2017-005763 Application 12/228,892 targeting moiety is bound to a target. Id. The Examiner further finds that Pallenberg teaches that, upon binding to a target, the acceptor moiety, such as the quenching agent, dissociates or moves away from the donor agent, such as the photosensitizer, whereby the donor is activated or active. Id. The Examiner finds that Pallenberg teaches, by way of example, that for conjugates containing a photosensitizer, binding to the target results in activation of the photosensitizer upon irradiation with light of a suitable wavelength. Id. The Examiner also finds that Pallenberg teaches antibodies as targeting moieties. Id. (citing Pallenberg ,r,r 49, 66, 143-145, 246, and claims 7, 8). The Examiner concludes that it would have been obvious to a person of ordinary skill in the art to substitute the antibody used in the antibody- targeted red blood cells of Coller for the antibody-based targeting molecules taught by Pallenberg. Final Act. 4. The Examiner concludes that a person of ordinary skill would have been motivated to combine the references to gain the advantage taught by Pallenberg that their modified antibodies are essentially non-toxic and inert until they bind the desired target antigen whereupon they become activated. Id. Appellants argue that there would have been no need for the advantage found by the Examiner, because the targeting disclosed in Coller was found to be: (1) "safe material" ( citing Coller col. 4); (2) advantageous because it is not subject to non-specific endocytosis (id. at col. 27); (3) precise in targeting specific tissues (id. at, e.g., cols. 4, 5); and (4) as achieving "highly selective binding" and "specific targeting of a drug to the site where it is needed" (id. at col. 17). App. Br. 14. 6 Appeal2017-005763 Application 12/228,892 According to Appellants, the stated advantage of Pallenberg, viz., that its "modified antibodies are essentially non-toxic and inert until they bind the desired target antigen," was used by the Examiner as supplying motivation for combining the references. App. Br. 15. Appellants contend that the Examiner finds that the antibodies of Coller result in systemic toxicity and are not inert before binding, notwithstanding numerous statements in Coller to the contrary. Id. Furthermore, Appellants assert, it is not the antibodies of Pallenberg that are non-toxic and inert until binding the desired antigen: Appellants point out that the Examiner agreed with Appellants that the antibodies do not have "any toxic effect in and of themselves." Id. (quoting Final Act. 7). Rather, Appellants argue, Pallenberg teaches that it is the photosensitizer that is non-toxic until bound to a target. Id. (citing, e.g., Pallenberg ,r 7). Appellants assert that Coller neither teaches nor suggests a photosensitizer, making it unclear to Appellants what the Examiner found to be toxic and active in Coller's compositions. App. Br. 15. Appellants argue that the Examiner finds that the problem addressed by Coller is the "side effects of conventional chemotherapeutic agents, such as nausea, hair loss, and fatigue." Id. (citing Final Act. 5). Appellants note, however, that the compositions of Coller that include chemotherapeutic agents are taught as being loaded in the erythrocytes to avoid indiscriminate delivery. Id. ( citing Coller col. 17). Appellants contend that the Examiner's finding of an "increased level of safety" as motivation to combine the references is specious because the substitution of the antibody of Coller for the complexed antibody of Pallenberg results in the addition of a toxic therapy. App. Br. 16. 7 Appeal2017-005763 Application 12/228,892 Appellants assert that the Examiner has failed to explain, and failed to cite any factual evidence, as to how the addition of a photodynamic therapeutic system provides improved safety. Id. Furthermore, Appellants question why a person of ordinary skill in the art would make such a substitution, when Coller already discloses a means of delivering a drug to a specific target. App. Br. 16. Appellants point to the Examiner's finding that adding photodynamic therapy agents makes Coller's erythrocytes with antibodies on them safer. Id. However, Appellants argue that not all of the compositions of Coller recite chemotherapeutic agents loaded into erythrocytes, rather, Appellants argue, Coller teaches a variety of materials for targeted delivery, including imaging agents, enzyme, neurotoxin, growth factor, hormone, nucleic acid sequences for gene therapy, anti-sense RNA or DNA, sperm, plasmids, modified virus or viral nucleic acids. Id. Appellants assert that the Examiner focused only on one of a number of compositions of Coller, i.e., that of a red blood cell loaded with a chemotherapeutic agent, and used it to allege a motivation. Id. at 16-17. We do not find Appellants arguments persuasive. Coller teaches a method for the targeted delivery of different agents, including chemotherapeutic agents, via peptides, including antibodies, bound to erythrocyte cell membranes. Specifically, Coller teaches: According to the instant invention, erythrocytes, or in particular thrombo-erythrocytes, prepared in accordance with the present invention can be modified for delivery, to various target tissues, of labels or biologically active agents that have been incorporated into the erythrocytes (i.e. taken up by erythrocyte ghosts) to form carrier erythrocytes .... 8 Appeal2017-005763 Application 12/228,892 The carrier erythrocytes have advantages over liposomes by virtue of their larger size, which avoids the problem of non- specific endocytosis of liposomes by scavenging cells such as macrophages, and because of the presence of an extensive cytoskeleton, that, for example, protects the erythrocytes from complete osmotic lysis under hypotonic conditions. Moreover, the cell surface integral membrane proteins of erythrocytes provide a convenient scaffold for cross-linking targeting molecules. Most importantly, since erythrocytes are inherently biocompatible, the carrier erythrocytes are more likely also to be biocompatible. Coller col. 17, 11. 14--35 (emphasis added). Coller thus teaches that red blood cells are highly advantageous for the targeted delivery of biologically active agents (including cytotoxic agents, see, e.g., col. 17, 11. 49--54) for numerous reasons, including especially their biocompatibility. Pallenberg teaches: [C]onjugates ... includ[ing] a fluorophore or photosensitizer linked to a targeting moiety and a quenching agent in such a way that activation of the fluorophore or the photosensitizer is quenched unless the targeting moiety is bound to a target, whereupon the quenching agent dissociates or moves away from the photosensitizer, enabling activation of the photo sensitizer upon irradiation with light of a suitable wavelength. Pallenberg Abstr. Pallenberg teaches that its targeting agents include: "compound[ s] that home[ ] in on or preferentially associate[ ] or bind[ ] to a particular tissue, receptor, infecting agent or other area of the body of the subject to be treated, such as a target tissue or target composition," and can include, inter alia, an antibody. Pallenberg ,r 66. Pallenberg also teaches that the term: "photosensitizer" or "photo sensitizing agent" denotes a chemical compound that upon exposure to photoactivating light is activated, converting the photosensitizing agent itself, or some other species, into a 9 Appeal2017-005763 Application 12/228,892 cytotoxic form, whereby target cells are killed or their proliferative potential diminished." Id. at 21. Pallenberg further teaches that: Virtually any chemical compound that, upon exposure to photoactivating light, is converted into or gives rise to a cytotoxic form may be used in this invention. Generally, the chemical compound is nontoxic to the animal to which it is administered or is capable of being formulated in a nontoxic composition, and the chemical compound in its photodegraded form is also nontoxic. Id. Pallenberg thus teaches all of the limitations of the claims, with the exception of teaching that its composition is bound to the surface of a red blood cell. Appellants do not dispute these findings. We agree with the Examiner that a person of ordinary skill in the art would have been motivated to combine the teachings of Coller and Pallenberg to arrive at Appellants' claimed invention. Such a combination would combine the directed targeting of both references with the several advantages of Coller, quoted supra, of delivering a targeting agent bound to the cell membrane of an erythrocyte, with the photoactivated cytotoxicity of Pallenberg' s compositions. Appellants argue, essentially, that because both mechanisms are "safe" to administer, there would be no motivation to combine. We disagree; in fact, we find that the Examiner's findings that both methods are safe to use would be a factor contributing to a person of ordinary skill's motivation to combine the references, because both methods can be practiced together, without risk of generally toxic, or other dangerous effects, from either. We conclude that a person of ordinary skill, understanding the teachings of Coller and Pallenberg, would be motivated to combine the advantages of using a targeted molecule bound to the cell 10 Appeal2017-005763 Application 12/228,892 membrane of an erythrocyte taught by Coller, with the photoactivatable cytotoxic agent of Pallenberg, because, unlike other cytotoxic agents, Pallenberg teaches that its compositions are not cytotoxic until illuminated by electromagnetic radiation of the requisite wavelength. See, e.g., Pallenberg ,r 21. We consequently affirm the Examiner's rejection upon this ground. Issue 2 Appellants argue that the Examiner erred in finding that claims 3 and 4 are unpatentable because the combination of Coller and Pallenberg fail to teach the limitations of the claims reciting: "wherein the target is selected from the group consisting of at least one of ... diseased cells in which the disease is one of an autoimmune and an inflammatory disease" and "wherein the target includes at least one of a bacteria .... ," respectively. App. Br. 9. Analysis Appellants point to the language of the Final Office Action, in which the Examiner finds: "[s]uch a combination [of Pallenberg's photodynamic antibody complexes and Coller's antibody-targeted RBCs] would be particularly useful in the cancer treatment methods of Collar [sic]." App. Br. 10 ( quoting Final Act. 4 ). By contrast, Appellants argue, the claims recite, in relevant part, that the targets are "diseased cells in which the disease is one of an autoimmune and an inflammatory disease" and "bacteria." Id. Appellants note that the Examiner then made two unsubstantiated allegations: (1) "that such a delivery system would also reduce systemic toxicity for all other disclosed diseases and disorders, such as bacterial 11 Appeal2017-005763 Application 12/228,892 infections as also disclosed by Pallenberg et al."; and (2) "that cancer and bacterial infections are inflammatory diseases." Id. ( quoting Final Act. 4). Appellants assert that, in response to their request that these statements, the Examiner provided four additional references4 to support the allegation that "cancer and bacterial infections are inflammatory diseases." App. Br. 10. However, Appellants argue, these references do not support the Examiner's position that cancer is an inflammatory disease, but rather merely state an "association" of inflammation with some malignancies. Id. Similarly, Appellants contend, the Examiner has conceded that there is a link between bacterial infections and inflammation, but Appellants assert that association is not the same thing as identity. Id. Appellants argue at some length that there is no identity between the nature of cancer and inflammation. Id. We are not persuaded by Appellants' argument. Coller is not restricted solely to the use of chemotherapeutic agents against neoplasms. Rather, Coller teaches that: In another embodiment, the carrier erythrocyte can be loaded with one or more therapeutic agents. For example, and not by way of limitation, the therapeutic agent can be a chemotherapeutic, an enzyme, a neurotoxin, a growth factor, a neurotrophic factor, a hormone, a thrombolytic agent, or any 4 A. Federico et al., Chronic inflammation and oxidative stress in human carcinogenesis, 121 INT'LJ. CANCER 2381-86 (2007) ("Federico"); S.A. Weitzman et al., Inflammation and cancer: role of phagocyte-generated oxidants in carcinogenesis, 76(4) BLOOD 655-63 (1990) ("Weitzman"); J. Parsonnet, Bacterial Infection as a Cause of Cancer, 103 (Supp. 8) EXP. HEALTH PERSPEC. 263---68 (1995) ("Personnet"); Merck Manual of Diagnosis and Therapy, Chapters 155-157, 1135-1209 (Seventeenth Ed. 1999) ("Merck Manual" 12 Appeal2017-005763 Application 12/228,892 drug. Generally, specific targeting of a drug to the site where it is needed results in more effective therapy because a larger therapeutic dose can be delivered than could be tolerated systemically. Coller col. 17, 11. 48-57. Pallenberg is directed to: [C]onjugates, kits, articles of manufacture and methods for detection, diagnosis and treatment by photodynamic therapy of certain undesired biological substrate targets, including, but not limited to bacteria, viruses, and other pathogenic microorganisms, tumors and hyperproliferative tissue. Pallenberg Abstr. Specifically, Pallenberg teaches: "Target compositions" as used herein are those compositions that are intended to be impaired or destroyed by this treatment method, and may include one or more pathogenic agents, including but not limited to bacteria, viruses, fungi, protozoa, and toxins as well as cells and tissues infected or infiltrated therewith. Id. at ,r 53 (emphasis added). Pallenberg teaches further that: "Hyperproliferative disorders" as used herein denotes those conditions sharing as an underlying pathology excessive cell proliferation caused by unregulated or abnormal cell growth, and include uncontrolled angiogenesis. Examples of such hyperproliferative disorders includes, but are not limited to ... psoriasis, atherosclerosis, psoriatic arthritis, rheumatoid arthritis .... Id. at ,r 55 (emphases added). Psoriasis, psoriatic arthritis, and rheumatoid arthritis are all well known in the art to be inflammatory autoimmune diseases. Given these teachings of the cited prior art, we do not find persuasive Appellants' argument that Coller and Pallenberg fail to teach or suggest the disputed limitations of claims 3 and 4. 13 Appeal2017-005763 Application 12/228,892 B. Rejection of claims 1--4 over Hamdy and Pallenberg Issue 1 Appellants argue the Examiner erred because neither prior art reference teaches or suggests the limitation of claim 1 reciting "red blood cell including at least one target-binding agent including a target recognition moiety." App. Br. 18. Analysis Appellants argue that Hamdy only incidentally teaches applying an anti-CD20 scFv to erythrocytes as a means to demonstrate the presence of a functional GPI anchor. App. Br. 18 (citing Hamdy 122). Rather, Appellants point to Hamdy's statement that: "Our ultimate goal is to use the anti-CD20 scFv to target liposome-encapsulated drugs to CD20-expressing hematological malignancies." Id. at 19. Appellants argue that, even if the teachings of Hamdy and Pallenberg can be properly combined, the combination of the references results in liposomes carrying photodynamic therapeutic antibodies, rather than erythrocytes. Id. We do not find Appellants' argument persuasive. Hamdy is entitled: "Sheep red blood cells armed with anti-CD20 single-chain variable fragments (scFvs) fused to a glycosylphosphatidylinositol (GPI) anchor: a strategy to target CD20-positive tumor cells." (Emphasis added). Further, Hamdy expressly teaches as the object of its reported study: "We show that this GPI-tagged scFv can be loaded onto the surface of sheep erythrocytes (Esh), which then specifically form rosettes with CD20-bearing tumor cells" and that: In order to demonstrate the presence of a functional GPI anchor, we "painted" sheep erythrocytes with the GPI-tagged anti-CD20 scFv and formed rosettes after incubation with WSU-FSCCL 14 Appeal2017-005763 Application 12/228,892 cells. These experiments demonstrate that the binding of the scFv to erythrocyte membranes is attributable to the GPI moiety, whereas the scFv specifically recognized the CD20 antigen on WSU-FSCCL cells. Hamdy 111, 122. Although we agree with Appellants that Hamdy also teaches: "Our ultimate goal is to use the anti-CD20 scFv to target liposome- encapsulated drugs to CD20-expressing hematological malignancies; therefore the glycosylphosphatidylinositol signal (GPI) of alkaline phosphatase was attached to the C-terminus of the scFv" (Hamdy 122), we agree with the Examiner that the stating of this aspiration in no way detracts from the fact that Hamdy expressly teaches "red blood cell including at least one target-binding agent including a target recognition moiety." Issue 2 Appellants argue that the Examiner erred because a person of ordinary skill in the art would not have been motivated to combine the teachings of Hamdy and Pallenberg. App. Br. 20. Appellants rely upon essentially the same arguments advanced with respect to the Examiner's combination of Coller and Pallenberg, viz., that neither reference teaches or suggests that at the antibody is anything but non-toxic. Id. at 20-21. We have explained supra why we are not persuaded by Appellants' arguments. We consequently affirm the Examiner's rejection of claims 1--4 on this ground. 15 Appeal2017-005763 Application 12/228,892 C. Rejection of claims 1-5 over Coller, Pallenberg, and Wilson Appellants rely upon the same arguments presented in Sections A and B supra with respect to the rejection of claims 1--4 over Coller and Pallenberg. App. Br. 21-24. Appellants assert that Wilson does not cure the alleged deficiencies of Coller and Pallenberg. Id. at 11. Because, for the reasons we have explained with respect to that rejection, we do not find Appellants' arguments persuasive, we affirm the Examiner's rejection of claims 1-5 on this ground. 5 DECISION The Examiner's rejection of claims 1-5 as unpatentable under 35 U.S.C. § 103(a) is affirmed. The Examiner's rejection of claims as unpatentable under the judicially-created doctrine of obviousness-type double patenting is affirmed. No time period for taking any subsequent action in connection with this appeal maybe extended under 37 C.F.R. § 1.136(a)(l). See 37 C.F.R. § 1.136(a)(l )(iv). AFFIRMED 5 Appellants also argue the patentability of claims 6-8. App. Br. 24. The claims have been withdrawn as being directed to a non-elected species. Final Act. 2. Since these claims are not presented on appeal, we do not reach Appellants' arguments. 16 Copy with citationCopy as parenthetical citation