DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Application Status
The amended claims filed May 20, 2026 are acknowledged. Claims 9-10, 15, and 19 have been amended. Claims 1-21 are pending and under examination herein.
Nucleotide and/or Amino Acid Sequence Disclosures
Applicant’s amendments to Figure 1 place the application in compliance with the Requirements for Patent Applications Containing Nucleotide and/or Amino Acid Sequence Disclosures.
Information Disclosure Statement
Applicant’s duty to disclose information material to the patentability of the claimed invention is noted.
In the instant application, the Examiner would like to note that Applicant has submitted an information disclosure statement with a total of 840 references. While the Examiner has made every effort to thoroughly review these references, one could have very well missed a pertinent document.
As noted in MPEP § 2004, “it is desirable to avoid the submission of long lists of documents if it can be avoided”. If a long list is submitted, Applicant has an obligation to call the most pertinent prior art to the attention of the Patent Office in a proper fashion and not “to disclose a pertinent prior art patent reference to the examiner in such a way as to ‘bury’ it or its disclosures in a series of disclosures of less relevant prior art references” (See Penn Yan Boats, Inc. v. Sea Lark Boats, Inc., 359 F. Supp. 948, 175 USPQ 260 (S.D. Fla. 1972), Golden Valley Microwave Food Inc. v. Weaver Popcorn Co., 837 F. Supp. 1444, 24 USPQ2d 1801 (N.D. Ind. 1992)).
WITHDRAWN OBJECTIONS AND REJECTIONS
The objections to the specification and Drawings are withdrawn in view of the substitute specification and replacement Drawings submitted May 20, 2026.
The objection to claim 19 is withdrawn in view of Applicant's amendments to the claim.
The provisional rejections of claims 1-9 and 16-21 under on the ground of nonstatutory double patenting as being unpatentable over claims 53-57 of co-pending Application No. 19/234,097 in view of Bernett (US 2016/0355608 A1), FDA (Rituxan™ Label (PDF), Webpage: “Rituximab Product Approval Information – Licensing Action”), and Du (Autoimmunity Highlights (2017) 8: 12), and further in view of Lazar (US 2014/0294812 A1), are withdrawn in view of the abandonment of the co-pending reference application.
MAINTAINED REJECTIONS
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
(1)
Claims 1-2, 5-9, and 16-21 are rejected under 35 U.S.C. 103 as being unpatentable over Bernett (US 2016/0355608 A1; cited in PTO-892 mailed November 2025) in view of United States Food and Drug Administration (Rituxan™ Label (PDF), Webpage: “Rituximab Product Approval Information – Licensing Action”, publicly available on or before May 16, 2016, accessed via Wayback Machine; hereafter “FDA”; cited in PTO-892 mailed November 2025) and Du (Autoimmunity Highlights (2017) 8: 12; cited in PTO-892 mailed November 2025).
Bernett discloses heterodimeric antibodies that bind to CD3 and tumor antigens. In one aspect, Bernett provides for an anti-CD20 antibody binding domain comprising VH CDR amino acid sequences of SYNMH, AIYPGNGATSYSQKFQG, and SYYMGGDWYFDV, respectively (which share 100% sequence identity to instant SEQ ID NO: 3, 4, and 5, respectively) and VL CDR amino acid sequences of RASWSVSYIH, ATSNLAS, and QQWTHNPPT, respectively (which share 100% sequence identity to instant SEQ ID NO: 9-11, respectively) (e.g., ¶ 0019-0020), relevant to claim 1. Bernett teaches that in some embodiments, the anti-CD20 antibody binding domains have the C2B8 H1.202_L1.113 (e.g., ¶ 0020). Bernett illustrates an exemplary construct comprising an anti-CD20 heavy chain having SEQ ID NO: 362 (for which residues 1-121 share 100% sequence identity with the instantly claimed VH amino acid sequence of instant SEQ ID NO: 2) and a corresponding light chain having SEQ ID NO: 364 (for which residues 1-106 share 100% sequence identity with the instantly claimed VL amino acid sequence of instant SEQ ID NO: 8 and for which all 213 residues share 100% sequence identity to instant SEQ ID NO: 7) (e.g., Figure 87 on Sheet 120 of 204), relevant to claims 2 and 10.
Further relevant to claim 1, Bernett discloses that there are a number of useful substitutions that can be incorporated into the antibody Fc to confer altered binding to FcγR receptors (e.g., 239D/332E) or increased serum half-life (e.g., 428L/434S) (e.g., ¶ 0305-0306).
Relevant to claims 5-9, Bernett discloses methods of producing a heterodimeric antibody of the invention using host cells, expression vectors, and nucleic acids encoding said antibodies (e.g., ¶ 0024-0025, 0384-0388).
Relevant to claim 16, Bernett discloses pharmaceutical compositions comprising the antibodies of the invention (e.g., ¶ 0391-0396).
Relevant to claims 20-21, Bernett discloses that anti-CD20 compositions of the invention may be used to treat cancers such as non-Hodgkin's lymphoma and chronic lymphocytic leukemia (e.g., ¶ 0389-0390).
However, Bernett does not disclose a monospecific, bivalent anti-CD20 antibody comprising two identical heavy chain polypeptides and two identical light chain polypeptides. Bernett also does not expressly teach using an anti-CD20 antibody of the invention to treat autoimmune disease.
FDA’s Rituxan™ (rituximab) label teaches that rituximab is a genetically engineered chimeric murine/human monoclonal IgG1 kappa immunoglobulin antibody against CD20 composed of two heavy chains (451 amino acids) and two light chains (213 amino acids) (“Description”). Rituximab contains murine light chain and heavy chain variable region sequences and human constant region sequences (“Description”). Based on said description, rituximab is a monospecific, bivalent anti-CD20 antibody. FDA further discloses, “The Fab domain of Rituximab binds to the CD20 antigen on B-lymphocytes and the Fc domain recruits immune effector functions to mediate B-cell lysis in vitro. Possible mechanisms of cell lysis include complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC)” (“Clinical Pharmacology”). FDA discloses that rituximab is indicated for treatment of patients with relapsed or refractory low-grade or follicular, CD20 positive, B-cell non-Hodgkin's lymphoma (“Indications and Usage”). FDA teaches that in clinical studies, patients with relapsed or refractory low-grade or follicular B-cell non-Hodgkin's lymphoma who were administered rituximab experienced an overall 46-48% overall response rate, and disease-related signs and symptoms resolved in 64% of patients who showed said signs and symptoms at study entry (ORR) (“Clinical Studies”).
Du reviews the use of next-generation anti-CD20 monoclonal antibodies in the treatment of autoimmune disease. Du discloses, “Anti-CD20 monoclonal antibodies (mAbs) are used to achieve B cell depletion, and were initially developed to treat B cell proliferative disorders, including non-Hodgkin’s lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Anti-CD20 mAbs have subsequently been tested and used in the treatment of the autoimmune disorder rheumatoid arthritis (RA) based on the rationale that the removal of the autoantibody producing or T cell-activating B cells would lead to clinical improvement. The clear clinical benefits of anti-CD20 mAb treatment in RA, particularly in patients refractory to other available treatments, has led to the expansion of anti-CD20 mAbs for other autoimmune diseases with both T cell and B cell etiology, including systemic lupus erythematosus (SLE) and multiple sclerosis (MS)” (Introduction, page 1). See also Table 2 (page 3). Du notes that rituximab, the first anti-CD20 mAb developed as a therapeutic agent, was approved by the FDA for use in treating non-Hodgkin's lymphoma (NHL), chronic lymphocytic leukemia (CLL), rheumatoid arthritis (RA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (Introduction, pages 1-2), relevant to claims 17-19. Du discloses that many of the second-generation anti-CD20 antibodies (e.g., the humanized antibodies ocrelizumab, veltuzumab, and Obinutuzumab; the human antibody ofatumumab) have increased binding affinity to Fc receptors and/or increased ADCC to boost their efficacy (e.g., Introduction, page 2; Table 1).
In view of the above, it would have been obvious to one of ordinary skill in the art, before the filing date of the instantly claimed invention, to generate a monospecific, bivalent anti-CD20 antibody (e.g., having a similar structure to rituximab), wherein the antigen-binding domains comprise a VH having the amino acid sequence of instant SEQ ID NO: 2 (with its respective CDRs) and a VL having an amino acid sequence of instant SEQ ID NO: 8 (with its respective CDRs) and the heavy chain further comprises the amino acid substitutions of 239D, 332E, 428L, and 434S (such as taught by Bernett), and furthermore, to administer such an antibody in the treatment of a cancer or an autoimmune disease. The skilled artisan would have been motivated to do so because Bernett teaches that antibodies comprising said anti-CD20 antigen-binding domain have utility in the treatment of cancer, and FDA and Du further provide that monospecific anti-CD20 antibodies have been successfully used in the treatment of cancer and autoimmune diseases. Based on the teachings of Bernett, one would have been further motivated to incorporate the Fc substitutions of 239D and 332E because these substitutions alter Fc receptor binding and enhance ADCC (which Du notes is a feature that boosts efficacy of the second-generation anti-CD20 therapeutic antibodies) and the substitutions of 428L and 434S because these mutations increase the serum half-life of the therapeutic antibody. There would have been a reasonable expectation of success because (1) known work in one field of endeavor may prompt variations of it for use in the same field based on design incentives if the variations are predictable to those of ordinary skill in the art (e.g., incorporating the anti-CD20 antigen-binding domain taught by Bernett into a monospecific, bivalent antibody format, to be similarly used to treat cancer or an autoimmune disease), and (2) one of ordinary skill in the art would have recognized the utility of the specifically claimed Fc domain substitutions for increasing the efficacy of the therapeutic antibody (i.e., by enhancing ADCC and increasing serum half-life).
(2)
Claims 1, 3-4, and 10-15 are rejected under 35 U.S.C. 103 as being unpatentable over Bernett (US 2016/0355608 A1; supra) in view of FDA (Rituxan™ Label (PDF), Webpage: “Rituximab Product Approval Information – Licensing Action”; supra) and Du (Autoimmunity Highlights (2017) 8: 12; supra) as applied to claims 1-2, 5-9, and 16-21 above, and further in view of Lazar (US 2014/0294812 A1).
The teachings of Bernett are described in the 35 U.S.C. § 103 rejection above. As previously noted, Bernett discloses an anti-CD20 light chain having SEQ ID NO: 364 (which shares 100% sequence identity to instant SEQ ID NO: 7, e.g., Figure 87).
However, Bernett does not expressly disclose a monospecific, bivalent anti-CD20 antibody, comprising two heavy chain polypeptides each having the amino acid sequence of instant SEQ ID NO: 1, two light chain polypeptides each having the amino acid sequence of instant SEQ ID NO: 7, wherein the heavy chain constant domain comprises a human IgG1 CH1, a human IgG1 hinge region, and a variant human IgG2 Fc domain, comprising the amino acid sequence of instant SEQ ID NO: 6.
The teachings of FDA and Du are disclosed in the 35 U.S.C. § 103 rejection above.
Lazar discloses Fc domain variants having increased binding to the FcRn receptor and/or increased serum half-life (e.g., Abstract). Lazar notes that the engineered Fc domains of the invention may be adopted in various therapeutic antibodies, including anti-CD20 antibodies (e.g., ¶ 0137-0139). Lazar illustrates an exemplary anti-CD20 heavy chain with enhanced ADCC and an extended half-life (“Hybrid S239D/I332E/M428L/N434S”) with an amino acid sequence of SEQ ID NO: 76 (Figure 81G, sheet 175 of 197), for which residues 122-451 share 100% sequence identity to the constant domain having the amino acid sequence of instant SEQ ID NO: 6, relevant to claims 3-4. See sequence alignment below.
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Lazar shows that the substitution of M428L/N434S in the Fc domain of a hybrid IgG1/IgG2 Fc further increases FcRn binding compared to the effect observed in a wildtype IgG1 or IgG2 constant domain, and improves the on and off kinetic rate constants (i.e., rates of association and dissociation from the antigen) of the antibody compared to wildtype IgG1 Fc. See, e.g., Figures 26A-26B (sheet 46 of 197), Figure 27A (sheet 48 of 197), and Figure 29 (sheet 51 of 197).
Together, the anti-CD20 VH disclosed by Bernett (which shares 100% sequence identity to residues 1-121 of instant SEQ ID NO: 1) and the enhanced hybrid IgG1/2 constant domain disclosed by Lazar (which shares 100% sequence identity to residues 122-451 of instant SEQ ID NO: 1) could be combined to arrive at an anti-CD20 heavy chain comprising the amino acid sequence of instant SEQ ID NO: 1, relevant to claim 10 and its dependent claims.
It would have been obvious to one of ordinary skill in the art, before the filing date of the instantly claimed invention, to arrive at a monospecific, bivalent anti-CD20 antibody having a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 7, wherein the heavy chain constant region comprises the enhanced hybrid IgG1/2 constant region taught by Lazar. The skilled artisan would have been motivated to do so because Lazar teaches that the enhanced hybrid IgG1/2 constant region comprising the amino acid sequence of instant SEQ ID NO: 6 has favorable pharmacokinetic properties compared to wildtype IgG1 or IgG2, in addition to having mutations known to confer enhanced ADCC (239D and 332E) and longer serum half-life (428L and 434S). There would have been a reasonable expectation of success because Lazar discloses that said enhanced hybrid constant regions can be incorporated into the heavy chain of an anti-CD20 antibody construct, and it is prima facie obvious to use a known technique to improve a similar product (i.e., an anti-CD20 antibody) in the same way.
Response to Arguments
Applicant's arguments filed May 20, 2026 have been fully considered but they are not persuasive.
Applicant argues that a person having ordinary skill in the art would lack motivation to combine Bernett with either FDA, Du, and/or Lazar with a reasonable expectation of success. Applicant states that “Because of Bernett’s disclosure of XENP13677’s less favorable therapeutic profile including rapid recovery of B cells at low doses” compared to another disclosed antibody, XENP13676, “a person of ordinary skill in the art would not be motivated to combine Bernett with FDA, Du, and/or Lazar, let alone have a reasonable expectation of success, especially for treating autoimmune diseases as claimed”. Remarks at pages 8-9. Applicant further submits that evidence of unexpected results for the instantly claimed antibodies demonstrates their non-obviousness. Applicant highlights that the claimed antibodies have surprisingly greatly enhanced expression yield, unexpectedly enhanced ADCC potency, and enhanced exposure (which Applicant suggests enables longer lasting anti-tumor activity) in comparison to rituximab Fv. Remarks at pages 9-10.
Regarding Applicant's arguments with respect to motivation to combine the cited references, it is noted that non-preferred or alternative embodiments still constitute prior art. As set forth in MPEP § 2123 (II), “Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). "A known or obvious composition does not become patentable simply because it has been described as somewhat inferior to some other product for the same use." In re Gurley, 27 F.3d 551, 554, 31 USPQ2d 1130, 1132 (Fed. Cir. 1994) … Furthermore, ‘[t]he prior art’s mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed….’ In re Fulton, 391 F.3d 1195, 1201, 73 USPQ2d 1141, 1146 (Fed. Cir. 2004).”
Regarding Applicant's statements regarding unexpected results, it is first noted that the incorporation of 239D/332E substitutions in the Fc region is a manipulation in the art known to confer improved ADCC potency. Accordingly, the observation that the instantly claimed antibodies possesses improved ADCC potency relative to a rituximab Fv construct lacking these mutations cannot be considered unexpected given the level of knowledge and skill of one of ordinary skill in the art. As set forth in MPEP § 716.02(c) (II), “‘Expected beneficial results are evidence of obviousness of a claimed invention…’ In re Gershon, 372 F.2d 535, 538, 152 USPQ 602, 604 (CCPA 1967)”. Secondly, Applicant states in their disclosure that the anti-CD20 biobetter molecules of the invention were prepared by humanizing and affinity-optimizing the variable region (Fv) of rituximab (e.g., ¶ 0098). While Applicant’s arguments highlight advantageous properties of the instantly claimed antibodies relative to rituximab, Applicant does not compare unexpected properties of the instantly claimed antibodies to those disclosed in the prior art by Bernett. Nonetheless, it is also noted that, as set forth in MPEP § 2145 (II), “[m]ere recognition of latent properties in the prior art does not render nonobvious an otherwise known invention”.
Accordingly, for at least these reasons, the rejections are maintained.
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
(1)
Claims 1-2, 5-9, and 16-21 are rejected on the ground of nonstatutory double patenting as being unpatentable over claim 1 of U.S. Patent No. 11,859,011 in view of Bernett (US 2016/0355608 A1; supra), FDA (Rituxan™ Label (PDF), Webpage: “Rituximab Product Approval Information – Licensing Action”; supra), and Du (Autoimmunity Highlights (2017) 8: 12; supra).
Reference patent claim 1 recites a composition comprising an anti-CD20 antigen-binding domain comprising a combination of VH and VL CDRs identical to those recited in instant claim 1.
However, the reference patent claims do not recite a monospecific, bivalent anti-CD20 antibody comprising said combination of CDRs, further comprising a variant Fc domain having the amino acid substitutions of 239D, 332E, 428L, and 434S, numbered according to EU numbering.
The teachings of Bernett, with respect to an anti-CD20 antigen-binding domain comprising identical heavy chain and light chain CDRs, is recited in the 35 U.S.C. § 103 rejection above.
The further teachings of FDA and Du are recited in the 35 U.S.C. § 103 rejection above.
It would have been obvious to one of ordinary skill in the art, before the filing date of the instantly claimed invention, to generate a monospecific, bivalent anti-CD20 antibody (e.g., having a similar structure to rituximab), wherein the antigen-binding domains comprise a VH having the amino acid sequence of instant SEQ ID NO: 2 (having the same heavy chain CDRs as those recited in the reference patent) and a VL having an amino acid sequence of instant SEQ ID NO: 8 (having the same light chain CDRs as those recited in the reference patent), and wherein the heavy chain further comprises the amino acid substitutions of 239D, 332E, 428L, and 434S (such as taught by Bernett). The skilled artisan would have been motivated to do so because Bernett teaches that antibodies comprising said anti-CD20 antigen-binding domain have utility in the treatment of cancer, and FDA and Du further provide that monospecific anti-CD20 antibodies have also been successfully used in the treatment of cancer and autoimmune diseases. Based on the teachings of Bernett, one would have been further motivated to incorporate the Fc substitutions of 239D and 332E because these substitutions alter Fc receptor binding and enhance ADCC (which Du notes is a feature that boosts efficacy of the second-generation anti-CD20 therapeutic antibodies) and the substitutions of 428L and 434S because these mutations increase the serum half-life of the therapeutic antibody. There would have been a reasonable expectation of success because (1) known work in one field of endeavor may prompt variations of it for use in the same field based on design incentives if the variations are predictable to those of ordinary skill in the art (e.g., incorporating the anti-CD20 antigen-binding domain taught by Bernett into a monospecific, bivalent antibody format, to be similarly used to treat cancer or an autoimmune disease), and (2) one of ordinary skill in the art would have recognized the utility of the specifically claimed Fc domain substitutions for increasing the efficacy of the therapeutic antibody (i.e., by enhancing ADCC and increasing serum half-life).
(2)
Claims 1, 3-4, and 10-151 are rejected on the ground of nonstatutory double patenting as being unpatentable over claim 1 of U.S. Patent No. 11,859,011 in view of Bernett (US 2016/0355608 A1; supra), FDA (Rituxan™ Label (PDF), Webpage: “Rituximab Product Approval Information – Licensing Action”; supra), and Du (Autoimmunity Highlights (2017) 8: 12; supra) as applied to claims 1-2, 5-9, and 16-21 above, further in view of Lazar (US 2014/0294812 A1; supra).
The teachings of the reference patent are recited in the non-statutory double patenting rejection above.
However, the reference patent does not expressly disclose a monospecific, bivalent anti-CD20 antibody, comprising two heavy chain polypeptides each having the amino acid sequence of instant SEQ ID NO: 1 and two light chain polypeptides each having the amino acid sequence of instant SEQ ID NO: 7, wherein the heavy chain constant domain comprises a human IgG1 CH1, a human IgG1 hinge region, and a variant human IgG2 Fc domain, comprising the amino acid sequence of instant SEQ ID NO: 6.
The teachings of Bernett, FDA, Du, and Lazar are disclosed in the 35 U.S.C. § 103 rejections above.
It would have been obvious to one of ordinary skill in the art, before the filing date of the instantly claimed invention, to arrive at a monospecific, bivalent anti-CD20 antibody having a heavy chain amino acid sequence of SEQ ID NO: 1 and a light chain amino acid sequence of SEQ ID NO: 7 (which comprise identical heavy chain and light chain CDRs, respectively, as disclosed in the reference patent), wherein the heavy chain constant region comprises the enhanced hybrid IgG1/2 constant region taught by Lazar. The skilled artisan would have been motivated to do so because Lazar teaches that the enhanced hybrid IgG1/2 constant region comprising the amino acid sequence of instant SEQ ID NO: 6 has favorable pharmacokinetic properties compared to wildtype IgG1 or IgG2, in addition to having mutations known to confer enhanced ADCC (239D and 332E) and longer serum half-life (428L and 434S). There would have been a reasonable expectation of success because Lazar discloses that said enhanced hybrid constant regions can be incorporated into the heavy chain of an anti-CD20 antibody construct, and it is prima facie obvious to use a known technique to improve a similar product (i.e., an anti-CD20 antibody) in the same way.
Response to Arguments
Applicant's arguments filed May 20, 2026 have been fully considered but they are not persuasive.
Applicant requests that the rejections be held in abeyance until the remaining rejections of record have been resolved.
In response, Applicant’s request to hold the nonstatutory double patenting rejections in abeyance is denied. The rejections will remain in place until they are overcome by amendment, terminal disclaimer, or otherwise.
Conclusion
No claims are allowed.
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/ELIZABETH A SHUPE/Examiner, Art Unit 1643
/JULIE WU/Supervisory Patent Examiner, Art Unit 1643
1 In the non-final Office Action mailed November 20, 2025, the rejection header contained an inadvertent typographical error stating that claims 1, 3-4, and 15-19, rather than claims 1, 3-4, and 10-14, were rejected in view of the cited references. Given that Lazar was cited in the 35 U.S.C. § 103 rejections above for its teachings of the limitations set forth in claims 1, 3-4, and 10-14, it is believed that the clear intent of citing Lazar was for its teachings related to claims 3-4 and 10-15 rather than claims 3-4 and 15-19. The Examiner apologizes for any inconvenience this inadvertent typographical error may have caused.
Prosecution Insights