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 .
Applicant’s election without traverse of Group I in the reply filed on December 23,2025 is acknowledged.
Claims 1-9, 15 and 16 are pending.
Claims 1-9, 15 and 16, drawn to multispecific antibody, are being acted upon in this Office Action.
Priority
Receipt is acknowledged of papers submitted under 35 U.S.C. 119(a)-(d), which papers have been placed of record in the file.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on Oct 1, 2025 and September 28, 2022 have been considered by the examiner and an initialed copy of the IDS is included with this Office Action.
Drawings
The drawings filed on September 28, 2022 are acceptable.
REQUIREMENTS FOR PATENT APPLICATIONS CONTAINING NUCLEOTIDE AND/OR AMINO ACID SEQUENCE DISCLOSURES
Items 1) and 2) provide general guidance related to requirements for sequence disclosures.
37 CFR 1.821(c) requires that patent applications which contain disclosures of nucleotide and/or amino acid sequences that fall within the definitions of 37 CFR 1.821(a) must contain a "Sequence Listing," as a separate part of the disclosure, which presents the nucleotide and/or amino acid sequences and associated information using the symbols and format in accordance with the requirements of 37 CFR 1.821 - 1.825. This "Sequence Listing" part of the disclosure may be submitted:
In accordance with 37 CFR 1.821(c)(1) via the USPTO patent electronic filing system (see Section I.1 of the Legal Framework for Patent Electronic System (https://www.uspto.gov/PatentLegalFramework), hereinafter "Legal Framework") as an ASCII text file, together with an incorporation-by-reference of the material in the ASCII text file in a separate paragraph of the specification as required by 37 CFR 1.823(b)(1) identifying:
the name of the ASCII text file;
ii) the date of creation; and
iii) the size of the ASCII text file in bytes;
In accordance with 37 CFR 1.821(c)(1) on read-only optical disc(s) as permitted by 37 CFR 1.52(e)(1)(ii), labeled according to 37 CFR 1.52(e)(5), with an incorporation-by-reference of the material in the ASCII text file according to 37 CFR 1.52(e)(8) and 37 CFR 1.823(b)(1) in a separate paragraph of the specification identifying:
the name of the ASCII text file;
the date of creation; and
the size of the ASCII text file in bytes;
In accordance with 37 CFR 1.821(c)(2) via the USPTO patent electronic filing system as a PDF file (not recommended); or
In accordance with 37 CFR 1.821(c)(3) on physical sheets of paper (not recommended).
When a “Sequence Listing” has been submitted as a PDF file as in 1(c) above (37 CFR 1.821(c)(2)) or on physical sheets of paper as in 1(d) above (37 CFR 1.821(c)(3)), 37 CFR 1.821(e)(1) requires a computer readable form (CRF) of the “Sequence Listing” in accordance with the requirements of 37 CFR 1.824.
If the "Sequence Listing" required by 37 CFR 1.821(c) is filed via the USPTO patent electronic filing system as a PDF, then 37 CFR 1.821(e)(1)(ii) or 1.821(e)(2)(ii) requires submission of a statement that the "Sequence Listing" content of the PDF copy and the CRF copy (the ASCII text file copy) are identical.
If the "Sequence Listing" required by 37 CFR 1.821(c) is filed on paper or read-only optical disc, then 37 CFR 1.821(e)(1)(ii) or 1.821(e)(2)(ii) requires submission of a statement that the "Sequence Listing" content of the paper or read-only optical disc copy and the CRF are identical.
Specific deficiencies and the required response to this Office Action are as follows:
Specific deficiency – The disclosure is objected to under 37 CFR 1.821 through 1.825 for failure to supply a sequence identifier to all disclosed sequences. In particular, the sequence LEVLFQGP at p. 43 is NOT present in the paper copy and computer readable copy of sequence listing. Hence, the disclosure fails to comply with the requirements of 37 CFR 1.821 through 1.825.
Required response – Applicant must provide:
a computer readable form (CFR) copy of the sequence listing in ST.25 format,
a substitute paper copy of the sequence listing, as well as any amendment directing its entry into the specification, and a statement that the content of the paper and computer readable copies are the same, and where applicable, include no new matter, as required by 37 CFR 1.82(e-f) or 1.825(b) or 1.825(d).
Amendment to the specification by inserting the corresponding Sequence identifier for LEVLFQGP at p. 43; and
A statement that the amendment contains no new matter.
Specification
The substitute specification filed September 29, 2025 has been entered.
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant's cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Claim Objection
Claims 1 and 9 are objected to because of the following informality: “including” should have been “comprising”.
Claims 1, 3-4, 6-7 are objected to because of the following informality: “includes” should have been “comprises”.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 8 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which applicant regards as the invention.
Claim 8 recites the limitation "single-chain antibody" in claim 1. There is insufficient antecedent basis for this limitation in the claim.
The recitation of “a single-chain antibody further binds to the variable region Va1 and/or the constant region Ca2” is indefinite because the phrase “binds to” has multiple meanings, for example, the single-chain antibody is linked to the variable region Va1 (FIG. 8) and/or the constant region Ca2 (FIG. 9)
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The phrase “binds to” can also mean the single-chain antibody having binding specificity toward the variable region Va1 and/or the constant region Ca2. Amending claim 8 to recite “The multispecific antibody according to claim 1 further comprising a single-chain antibody linked to N-terminus of the variable region Va1 and/or C-terminus of the constant region Ca2” would obviate this rejection. Appropriate correction is required.
Claim rejections under - 35 U.S.C. 112
The following is a quotation of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), first paragraph:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-9, 15 and 16 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for pre-AIA the inventor(s), at the time the application was filed, had possession of the claimed invention.
The Written Description Guidelines for examination of patent applications indicates, “the written description requirement for a claimed genus may be satisfied through sufficient description of a representative number of species by actual reduction to practice, or by disclosure of relevant, identifying characteristics, i.e., structure or other physical characteristics and/or other chemical properties, by functional characteristics coupled with a known or disclosed correlation between function and structure, or by a combination of such identifying characteristics, sufficient to show applicant was in possession of the claimed genus.” (see MPEP 2163).
Claim 1 encompasses any multispecific antibody comprising a Fab region that includes one polypeptide a chain below and two polypeptide b chains below:
the polypeptide a chain including a polypeptide in which a variable region Val, a constant region Cal, a peptide linker LL, a variable region Va2, and a constant region Ca2 are linked in the stated order; and
the polypeptide b chain including a polypeptide in which a variable region Vb is linked to a constant region Cb binding to the constant region Cal or the constant region C a2.
Claim 2 encompasses the multispecific antibody according to claim 1, wherein a length of the peptide linker LL is 70 to 280 A.
Claim 3 encompasses the multispecific antibody according to claim 1, wherein the peptide linker LL includes a protease recognition sequence.
Claim 4 encompasses the multispecific antibody according to claim 3, wherein the peptide linker LL includes a protease recognition sequence Lrl on the constant region Cal side and a protease recognition sequence Lr2 on the variable region Va2 side.
Claim 5 encompasses the multispecific antibody according to claim 1, wherein the multispecific antibody is IgD, IgE, IgG, or F(ab')2.
Claim 6 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a heavy-chain constant region CHal, a peptide linker LL, a heavy-chain variable region Vla2, and a heavy-chain constant region CHa2 are linked in the stated order.
Claim 7 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a light-chain constant region CLal, a peptide linker LL, a heavy-chain variable region Vla2, and a light-chain constant region CLa2 are linked in the stated order.
Claim 8 encompasses the multispecific antibody according to claim 1, wherein a single-chain antibody further binds to the variable region Val and/or the constant region Ca2.
Claim 9 encompasses any multispecific antibody comprising a Fab region including one polypeptide a' chain below, one polypeptide a" chain below, and two polypeptide b chains below:
the polypeptide a' chain including a polypeptide in which a variable region Val, a constant region Cal, and a cleavage fragment Lrl' of a protease recognition sequence Lrl are linked in the stated order;
the polypeptide a" chain including a polypeptide in which a cleavage fragment Lr2' of a protease recognition sequence Lr2, a variable region Va2, and a constant region Ca2 are linked in the stated order; and the polypeptide b chain including a polypeptide in which a variable region Vb is linked to a constant region Cb binding to the constant region Cal or the constant region Ca2.
Claim 15 encompasses any diagnostic agent comprising the multispecific antibody according to claim 1.
Claim 16 encompasses a pharmaceutical composition comprising the multispecific antibody according to claim 1. The genera encompassed by the claims are of large size and substantial variability.
Comparing the claim scope with the scope of the description, the specification as filed discloses:
Example 1: Design and Production of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-1)
[0194] (1) Design of Anti-HER2×HER3 Bispecific Antibody (HER2×HER3 TribsMab CLC)
[0195] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed.
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In this test example, the bispecific antibody was designed to target HER2 and HER3 expressed on the surface of tumor cells. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of MCLA-128 (Cancer Cell 33, 922-936 (2018)) known as the anti-HER2×Her3 bispecific antibody, that is, sequences of the heavy-chain variable region 3958VH (specific to HER2) and the heavy-chain variable region 3178VH (specific to HER3) of MCLA-128, and the light-chain variable region 128VL of MCLA-128 were adopted. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, peptide linkers with different lengths each having GGGGS as a basic sequence and including or not including the HRV3C protease recognition sequence (LEVLFQGP) were designed.
[0196] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the bispecific antibody designed in the present test example is shown in the following Tables 1 and 2, and the schematic diagram of the bispecific antibody designed in the present test example is shown in FIG. 18. Approximate calculation of specific lengths (A) and specific sequences of the peptide linkers with different lengths are as shown in Table 1. Each peptide linker is represented by L(x), “x” in parentheses indicates the total number of amino acid residues constituting the peptide linker in the case of those containing a protease recognition sequence (for example, a peptide linker which includes a protease recognition sequence and in which the total number of amino acid residues constituting the peptide linker is 68, is indicated as “L(68)”), and “delP” is added in the case of those not containing a protease recognition sequence.
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Test Example 2: Activity Evaluation of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-I)
[0224] (1) Binding Activity Evaluation-1
[0225] For the multispecific antibodies 12 of Examples 1 to 5 prepared in Test Example 1, binding activity evaluation by flow cytometry to HER2 and HER3-positive human mammary adenocarcinoma cells MCF-7 was performed as follows.
Test Example 3: Examination of Production Conditions of Multispecific Antibody
[0239] A multispecific antibody was prepared in the same manner as in Example 1, except that the introduction ratio of the recombinant vector va and the recombinant vector vb prepared in Test Example 1 was changed, and the generation amount of the tetramer 12BQ was confirmed in the same manner as in (5-2) of Test Example 1 on a gel filtration chromatogram. The introduction ratio (weight basis) of the recombinant vector va and the recombinant vector vb adopted in the present test example is shown in the following table. The introduction ratio (weight basis) of the recombinant vector va and the recombinant vector vb shown in the following table is substantially the same as the introduction ratio on a molar basis. In the following table, the introduction ratio in Example 1 prepared in Test Example 1 is also described.
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Test Example 4: Design and Production of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-2)
[0241] (1) Design of HER2×HER3 Bispecific Antibody
[0242] A bispecific antibody corresponding to the multispecific antibody 13 of FIG. 7 was designed. Specifically, the multispecific antibody 13 (Example 9) was designed in the same manner as in Example 1 in Test Example 1, except that the heavy-chain constant region CHa1 and the light-chain constant region CHb of the multispecific antibody 12 prepared in Example 1 of Test Example 1 were interchanged, and the heavy-chain constant region CHa2 and the light-chain constant region CHb were interchanged. The correspondence relationship between the domains of the multispecific antibody 13 (Example 9) of FIG. 7 and the bispecific antibody designed in the present test example is shown in the following Tables 5 and 6, and the schematic diagram of the bispecific antibody (Example 9) designed in the present test example is shown in FIG. 31.
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Test Example 5: Design and Production of Multispecific Antibodies (Anti-CD20×CD3 Bispecific Antibody and Anti-BCMA×CD3 Bispecific Antibody)
[0249] (1) Design of Bispecific Antibody
[0250] (1-1) Design of Anti-CD20×CD3 Bispecific Antibody (CD20×CD3 TribsMab CLC)
[0251] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed. The bispecific antibody was designed to target CD20 and CD3. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of REGN1979 (Eric J. Smith, Kara Olson, Lauric J. Haber, Bindu Varghese, Paurene Duramad. Sci Rep, 5, 17943 (2016)) known as the anti-CD20×CD3 bispecific antibody, that is, sequences of the heavy-chain variable region 1979VH-CD20 (specific to CD20) and the heavy-chain variable region 1979VH-CD3 (specific to CD3) of REGN1979, and the light-chain variable region 1979VL of REGN1979 were adopted. The light chain class of REGN1979 is λ. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, a peptide linker having GGGGS as a basic sequence was designed.
[0252] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the designed anti-CD20×CD3 bispecific antibody is shown in the following Tables 7 and 8, and the schematic diagram of the designed anti-CD20×CD3 bispecific antibody is shown in FIG. 35A.
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The correspondence relationship between the domains of the multispecific antibody 12 of Fig. 5 and the designed anti-CD20xCD3 bispecific antibody is shown in Tables 7 and 8.
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[0253] (1-2) Design of Anti-BCMA×CD3 Bispecific Antibody (BCMA×CD3 TribsMab CLC)
[0254] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed. The bispecific antibody was designed to target BCMA and CD3. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of pSCHLI372 (Japanese Patent Laid-open Publication No. 2018-502062) known as the anti-BCMA×CD3 bispecific antibody, that is, sequences of the heavy-chain variable region 372VH-BCMA (specific to BCMA) and the heavy-chain variable region 372VH-CD3 (specific to CD3) of pSCHLI372, and the light-chain variable region 372VL of pSCHLI372 were adopted. The light chain class of pSCHLI372 is K. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, a peptide linker having GGGGS as a basic sequence was designed.
[0255] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the designed anti-BCMA×CD3 bispecific antibody is shown in the following Tables 9 and 10, and the schematic diagram of the designed anti-BCMA×CD3 bispecific antibody is shown in FIG. 35B.
The correspondence relationship between the domains of the multispecific antibody 12 of Fig. 5 and the designed anti-BCMAxCD3 bispecific antibody is shown in Tables 9 and 10.
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Test Example 6: Activity Evaluation of Multispecific Antibodies (Anti-CD20×CD3 Bispecific Antibody and Anti-BCMA×CD3 Bispecific Antibody)
[0271] (1) Binding Activity Evaluation of Anti-CD20×CD3 Bispecific Antibody
[0272] For the anti-CD20×CD3 bispecific antibodies of Examples 10 and 11 prepared in Test Example 5 (purified by cation exchange chromatography), the binding activity to Raji cells (CD20-positive cells) and T-LAK cells (CD3-positive cells) was evaluated as follows.
[0285] Results are shown in FIG. 41B. As clearly shown from FIG. 41B, it was found that BCMA×CD3 TribsMab CLC of Examples 12 and 13 crosslinked the fluorescently labeled BCMA-ECD-Fc and the CD3-positive T-LAK cell.
Test Example 7: Bispecific Antibody with Linker Cleaved
[0286] The linker of HER2×HER3 TribsMab CLC of Example 1 was cleaved with an HRV3 protease to prepare Her2×HER3 TribsMab CLC (Example 14) in a linker-cleaved state.
[0287] To 1 mg of HER2×HER3 TribsMab CLC (after protein A purification) of Example 1, 5 μL of Turbo3C (HRV3C) protease (Funakoshi Co., Ltd.) was added, and the mixture was left to stand still at 4° C. overnight. Next, in order to remove the protease, purification was performed by column chromatography using Glutathione Sepharose 4B (GE Healthcare). After equilibration with PBS, each antibody solution was added and the flow-through was recovered. The remaining protease was eluted using an elution buffer (50 mM Tris-HCl, 10 mM reduced glutathione, pH 8.0) after the column was washed with PBS. The purified sample was analyzed by SDS-PAGE.
[0288] Results of SDS-PAGE are shown in FIG. 42. As clearly shown from FIG. 42, it could be confirmed that the linker of HER2×HER3 TribsMab CLC of Example 1 was cleaved, and the bispecific antibody of Example 14 was obtained.
[0289] The binding activity evaluation of the linker-cleaved HER2×HER3 TribsMab CLC of Example 14 obtained as described above by flow cytometry to HER2 and HER3-positive human mammary adenocarcinoma cells MCF-7 was performed.
[0290] Using MCF-7 cells cultured in a 10% FBS/DMEM medium, the linker-cleaved HER2×HER3 TribsMab CLC (500 nM) of Example 14 as a primary antibody was reacted with MCF-7 cells for 30 minutes, and then washed twice with 0.1% NaN.sub.3/PBS. Subsequently, 1 μL of an anti-human IgG (Fc-specific)-FITC antibody (Sigma Aldrich) as a secondary antibody and 499 μL of 0.1% NaN.sub.3/PBS were added and reacted for 30 minutes, and then washed twice with 0.1% NaN.sub.3/PBS. Thereafter, the cells were subjected to flow cytometric analysis using BD Accuri™ C6 (BD Biosciences).
[0291] Results are shown in FIG. 43. As clearly shown from FIG. 43, the linker-cleaved HER2×HER3 TribsMab CLC of Example 14 also maintained binding activity.
However, the specification does not describe the structure-identifying information, e.g., amino acid sequences of variable region Va1, variable region Va2, variable region Vb (claims 1, 9) or heavy-chain variable region VHa1, a heavy-chain variable region VHa2 (claim 6) or any single-chain antibody further binds to any variable region Va1 and/or the constant region Ca2, or Vb (claim 8) about the claimed multispecific antibodies. The specification fails to disclose a correlation between structure, e.g., and function, e.g., binding specificity of all multispecific antibodies. There is no limitation on the structure or function of the multispecific antibody, or the epitope to which it binds. The specification does not describe a representative number of species falling within the scope of the genus or structural features common to the members of the genus so the one of skill in the art can visualize or recognize the member of the genus of the actual claimed multispecific antibodies themselves. Thus, three species of bispecific antibodies fails to convey evidence of possession of the entire genus at the time of filing.
At the time the invention was made, it was known in the art that antibodies have a large repertoire of distinct structures and that a huge variety of antibodies can be made to bind to a single epitope.
For example, Lloyd et al. taught that hundreds of functional antibody fragments can be isolated from an antibody library that bind to the same antigen wherein these antibodies have distinct heavy and light chain sequences (Lloyd et al. Protein Engineering, Design & Selection 22:159-168, 2009; see, e.g., Discussion).
Similarly, Edwards et al. (J Mol Biol. 334(1): 103-118, 2003; PTO 892), found that over 1000 antibodies, all different in amino acid sequence, were generated to a single protein; 568 different amino acid sequences identified for the V(H) CDR3 domains of these antibodies (Abstract). Given that hundreds of unique antibody structures may bind a single antigen, the structure of an antibody cannot be predicted from the structure of the antigen (as held in Amgen), and a single species, or small group of species, cannot define a structure-function relationship so as to be representative of all the antibodies that bind to that antigen (as held in Abbvie).
Given the lack of guidance as to the binding specificity of the multispecific antibody, and the lack of in vivo working examples, it is unpredictable which undisclosed multispecific antibody is effective as a pharmaceutical composition (claim 16) for treating disease such as cancer or diagnostic agent (claim 15).
Regarding peptide linker LL, the specification discloses just protease cleavable peptide linker consisting of the amino acid sequence of SEQ ID NO: 2, 4, 5 and 6 that linked CHa1-CHa1 and VHa2-Cha2 wherein the peptide linker has a particular length in terms of Angstrom, see Table 1.
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However, one species of human rhinovirus 3C (HRV3C) protease recognition sequence LEVLFQGP is not representative of the genus of protease recognition sequences (claims 3-4, 9) and any peptide linker LL having a length between 70 and 280 Angstrom (claim 2).
Vas-Cath Inc. v. Mahurkar, 19 USPQ2d 1111, makes clear that “applicant must convey with reasonable clarity to those skilled in the art that, as of the filing date sought, he or she was in possession of the invention. The invention is, for purposes of the written description inquiry, whatever is now claimed.” (See page 1117.) The specification does not “clearly allow persons of ordinary skill in the art to recognize that [he or she] invented what is claimed.” (See Vas-Cath at page 1116.).
Adequate written description requires more than a mere statement that it is part of the invention and reference to a potential method for isolating it. See Fiers v. Revel, 25 USPQ2d 1601, 1606 (CAFC 1993) and Amgen Inc. v. Chugai Pharmaceutical Co. Ltd., 18 USPQ2d 1016.
One cannot describe what one has not conceived. See Fiddles v. Baird, 30 USPQ2d 1481, 1483. In Fiddles v. Baird, claims directed to mammalian FGF’s were found unpatentable due to lack of written description for the broad class. The specification provided only the bovine sequence. Thus, the specification fails to describe these DNA sequences.
For genus claims, an adequate written description of a claimed genus requires more than a generic statement of an invention's boundaries. A patent must set forth either a representative number of species falling within the scope of the genus or structural features common to the members of the genus. Kubin, Exparte, 83 USPQ2d 1410 (Bd. Pat. App. & Int. 2007); Ariad Pharms., Inc. v. Eli Lilly& Co., 598 F.3d 1336, 1350 (Fed. Cir. 2010).
Therefore, only (1) a multispecific antibody comprising a Fab region that comprise one polypeptide a chain and two polypeptide b chains wherein the polypeptide a chain comprises a first VH domain, a CL domain, a protease cleavable linker, a second VH domain linked to a CH1 domain in the stated order, wherein the polypeptide b chain each comprises a VL domain, a CL domain, a CH1 domain, a hinge, a CH2 and a CH3 domain in the stated order, wherein the protease cleavable linker consisting of the amino acid sequence selected from the group consisting of SEQ ID NO: 2, 4, 5, 6 and 7 and wherein the multispecific antibody binds to CD20 and CD3 or BCMA and CD3 or HER2 and HER3, (2) the multispecific antibody above further comprises a single chain antibody linked to N-terminus of the first VH domain and/or C-terminus of the CL domain, (3) a composition comprising said multispecific antibody and a pharmaceutically acceptable carrier, a diagnostic agent comprising said multispecific antibody, but not the full breadth of the claims meets the written description provision of 35 U.S.C. § 112, first paragraph. Applicant is reminded that Vas-Cath makes clear that the written description provision of 35 U.S.C. § 112 is severable from its enablement provision (see page 1115).
Claims 1-9, 15 and 16 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, because the specification, while being enabling for (1) a multispecific antibody comprising a Fab region that comprise one polypeptide a chain and two polypeptide b chains wherein the polypeptide a chain comprises a first VH domain, a CL domain, a protease cleavable linker, a second VH domain linked to a CH1 domain in the stated order, wherein the polypeptide b chain each comprises a VL domain, a CL domain, a CH1 domain, a hinge, a CH2 and a CH3 domain in the stated order, wherein the protease cleavable linker consisting of the amino acid sequence selected from the group consisting of SEQ ID NO: 2, 4, 5, 6 and 7, and wherein the multispecific antibody binds to CD20 and CD3 or BCMA and CD3 or HER2 and HER3, (2) the multispecific antibody above further comprises a single chain antibody linked to N-terminus of the first VH domain and/or C-terminus of the CL domain, (3) a composition comprising said multispecific antibody and a pharmaceutically acceptable carrier, a diagnostic agent comprising said multispecific antibody, does not reasonably provide enablement for any and all multispecific antibody as a pharmaceutical composition. The specification does not enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the invention commensurate in scope with these claims.
Enablement is considered in view of the Wands factors (MPEP 2164.01(a)). These factors include, but are not limited to: (A) The breadth of the claims; (B) The nature of the invention; (C) The state of the prior art; (D) The level of one of ordinary skill; (E) The level of predictability in the art; (F) The amount of direction provided by the inventor; (G) The existence of working examples; and (H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure. . In re Wands, 858 F.2d 731, 737, 8 USPQ2d 1400, 1404 (Fed. Cir. 1988).
Claim 1 encompasses any multispecific antibody comprising a Fab region that includes one polypeptide a chain below and two polypeptide b chains below:
the polypeptide a chain including a polypeptide in which a variable region Val, a constant region Cal, a peptide linker LL, a variable region Va2, and a constant region Ca2 are linked in the stated order; and
the polypeptide b chain including a polypeptide in which a variable region Vb is linked to a constant region Cb binding to the constant region Cal or the constant region C a2.
Claim 2 encompasses the multispecific antibody according to claim 1, wherein a length of the peptide linker LL is 70 to 280 Å.
Claim 3 encompasses the multispecific antibody according to claim 1, wherein the peptide linker LL includes a protease recognition sequence.
Claim 4 encompasses the multispecific antibody according to claim 3, wherein the peptide linker LL includes a protease recognition sequence Lrl on the constant region Cal side and a protease recognition sequence Lr2 on the variable region Va2 side.
Claim 5 encompasses the multispecific antibody according to claim 1, wherein the multispecific antibody is IgD, IgE, IgG, or F(ab')2.
Claim 6 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a heavy-chain constant region CHal, a peptide linker LL, a heavy-chain variable region Vla2, and a heavy-chain constant region CHa2 are linked in the stated order.
Claim 7 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a light-chain constant region CLal, a peptide linker LL, a heavy-chain variable region Vla2, and a light-chain constant region CLa2 are linked in the stated order.
Claim 8 encompasses the multispecific antibody according to claim 1, wherein a single-chain antibody further binds to the variable region Val and/or the constant region Ca2.
Claim 9 encompasses any multispecific antibody comprising a Fab region including one polypeptide a' chain below, one polypeptide a" chain below, and two polypeptide b chains below:
the polypeptide a' chain including a polypeptide in which a variable region Val, a constant region Cal, and a cleavage fragment Lrl' of a protease recognition sequence Lrl are linked in the stated order;
the polypeptide a" chain including a polypeptide in which a cleavage fragment Lr2' of a protease recognition sequence Lr2, a variable region Va2, and a constant region Ca2 are linked in the stated order; and the polypeptide b chain including a polypeptide in which a variable region Vb is linked to a constant region Cb binding to the constant region Cal or the constant region Ca2.
Claim 15 encompasses any diagnostic agent comprising the multispecific antibody according to claim 1.
Claim 16 encompasses a pharmaceutical composition comprising the multispecific antibody according to claim 1.
Example 1: Design and Production of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-1)
[0194] (1) Design of Anti-HER2×HER3 Bispecific Antibody (HER2×HER3 TribsMab CLC)
[0195] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed.
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In this test example, the bispecific antibody was designed to target HER2 and HER3 expressed on the surface of tumor cells. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of MCLA-128 (Cancer Cell 33, 922-936 (2018)) known as the anti-HER2×Her3 bispecific antibody, that is, sequences of the heavy-chain variable region 3958VH (specific to HER2) and the heavy-chain variable region 3178VH (specific to HER3) of MCLA-128, and the light-chain variable region 128VL of MCLA-128 were adopted. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, peptide linkers with different lengths each having GGGGS as a basic sequence and including or not including the HRV3C protease recognition sequence (LEVLFQGP) were designed.
[0196] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the bispecific antibody designed in the present test example is shown in the following Tables 1 and 2, and the schematic diagram of the bispecific antibody designed in the present test example is shown in FIG. 18. Approximate calculation of specific lengths (A) and specific sequences of the peptide linkers with different lengths are as shown in Table 1. Each peptide linker is represented by L(x), “x” in parentheses indicates the total number of amino acid residues constituting the peptide linker in the case of those containing a protease recognition sequence (for example, a peptide linker which includes a protease recognition sequence and in which the total number of amino acid residues constituting the peptide linker is 68, is indicated as “L(68)”), and “delP” is added in the case of those not containing a protease recognition sequence.
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Test Example 2: Activity Evaluation of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-I)
[0224] (1) Binding Activity Evaluation-1
[0225] For the multispecific antibodies 12 of Examples 1 to 5 prepared in Test Example 1, binding activity evaluation by flow cytometry to HER2 and HER3-positive human mammary adenocarcinoma cells MCF-7 was performed as follows.
Test Example 3: Examination of Production Conditions of Multispecific Antibody
[0239] A multispecific antibody was prepared in the same manner as in Example 1, except that the introduction ratio of the recombinant vector va and the recombinant vector vb prepared in Test Example 1 was changed, and the generation amount of the tetramer 12BQ was confirmed in the same manner as in (5-2) of Test Example 1 on a gel filtration chromatogram. The introduction ratio (weight basis) of the recombinant vector va and the recombinant vector vb adopted in the present test example is shown in the following table. The introduction ratio (weight basis) of the recombinant vector va and the recombinant vector vb shown in the following table is substantially the same as the introduction ratio on a molar basis. In the following table, the introduction ratio in Example 1 prepared in Test Example 1 is also described.
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Test Example 4: Design and Production of Multispecific Antibody (Anti-HER2×HER3 Bispecific Antibody-2)
[0241] (1) Design of HER2×HER3 Bispecific Antibody
[0242] A bispecific antibody corresponding to the multispecific antibody 13 of FIG. 7 was designed. Specifically, the multispecific antibody 13 (Example 9) was designed in the same manner as in Example 1 in Test Example 1, except that the heavy-chain constant region CHa1 and the light-chain constant region CHb of the multispecific antibody 12 prepared in Example 1 of Test Example 1 were interchanged, and the heavy-chain constant region CHa2 and the light-chain constant region CHb were interchanged. The correspondence relationship between the domains of the multispecific antibody 13 (Example 9) of FIG. 7 and the bispecific antibody designed in the present test example is shown in the following Tables 5 and 6, and the schematic diagram of the bispecific antibody (Example 9) designed in the present test example is shown in FIG. 31.
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Test Example 5: Design and Production of Multispecific Antibodies (Anti-CD20×CD3 Bispecific Antibody and Anti-BCMA×CD3 Bispecific Antibody)
[0249] (1) Design of Bispecific Antibody
[0250] (1-1) Design of Anti-CD20×CD3 Bispecific Antibody (CD20×CD3 TribsMab CLC)
[0251] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed. The bispecific antibody was designed to target CD20 and CD3. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of REGN1979 (Eric J. Smith, Kara Olson, Lauric J. Haber, Bindu Varghese, Paurene Duramad. Sci Rep, 5, 17943 (2016)) known as the anti-CD20×CD3 bispecific antibody, that is, sequences of the heavy-chain variable region 1979VH-CD20 (specific to CD20) and the heavy-chain variable region 1979VH-CD3 (specific to CD3) of REGN1979, and the light-chain variable region 1979VL of REGN1979 were adopted. The light chain class of REGN1979 is λ. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, a peptide linker having GGGGS as a basic sequence was designed.
[0252] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the designed anti-CD20×CD3 bispecific antibody is shown in the following Tables 7 and 8, and the schematic diagram of the designed anti-CD20×CD3 bispecific antibody is shown in FIG. 35A.
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The correspondence relationship between the domains of the multispecific antibody 12 of Fig. 5 and the designed anti-CD20xCD3 bispecific antibody is shown in Tables 7 and 8.
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[0253] (1-2) Design of Anti-BCMA×CD3 Bispecific Antibody (BCMA×CD3 TribsMab CLC)
[0254] A bispecific antibody corresponding to the multispecific antibody 12 of FIG. 5 was designed. The bispecific antibody was designed to target BCMA and CD3. As for the variable regions (portions surrounded by dashed lines in FIG. 5), the same sequences as those of the variable regions of pSCHLI372 (Japanese Patent Laid-open Publication No. 2018-502062) known as the anti-BCMA×CD3 bispecific antibody, that is, sequences of the heavy-chain variable region 372VH-BCMA (specific to BCMA) and the heavy-chain variable region 372VH-CD3 (specific to CD3) of pSCHLI372, and the light-chain variable region 372VL of pSCHLI372 were adopted. The light chain class of pSCHLI372 is K. As for the constant region, a sequence derived from the human IgG1 class was adopted. As a sequence corresponding to the peptide linker LL of FIG. 5, a peptide linker having GGGGS as a basic sequence was designed.
[0255] The correspondence relationship between the domains of the multispecific antibody 12 of FIG. 5 and the designed anti-BCMA×CD3 bispecific antibody is shown in the following Tables 9 and 10, and the schematic diagram of the designed anti-BCMA×CD3 bispecific antibody is shown in FIG. 35B.
The correspondence relationship between the domains of the multispecific antibody 12 of Fig. 5 and the designed anti-BCMAxCD3 bispecific antibody is shown in Tables 9 and 10.
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Test Example 6: Activity Evaluation of Multispecific Antibodies (Anti-CD20×CD3 Bispecific Antibody and Anti-BCMA×CD3 Bispecific Antibody)
[0271] (1) Binding Activity Evaluation of Anti-CD20×CD3 Bispecific Antibody
[0272] For the anti-CD20×CD3 bispecific antibodies of Examples 10 and 11 prepared in Test Example 5 (purified by cation exchange chromatography), the binding activity to Raji cells (CD20-positive cells) and T-LAK cells (CD3-positive cells) was evaluated as follows.
[0285] Results are shown in FIG. 41B. As clearly shown from FIG. 41B, it was found that BCMA×CD3 TribsMab CLC of Examples 12 and 13 crosslinked the fluorescently labeled BCMA-ECD-Fc and the CD3-positive T-LAK cell.
Test Example 7: Bispecific Antibody with Linker Cleaved
[0286] The linker of HER2×HER3 TribsMab CLC of Example 1 was cleaved with an HRV3 protease to prepare Her2×HER3 TribsMab CLC (Example 14) in a linker-cleaved state.
[0287] To 1 mg of HER2×HER3 TribsMab CLC (after protein A purification) of Example 1, 5 μL of Turbo3C (HRV3C) protease (Funakoshi Co., Ltd.) was added, and the mixture was left to stand still at 4° C. overnight. Next, in order to remove the protease, purification was performed by column chromatography using Glutathione Sepharose 4B (GE Healthcare). After equilibration with PBS, each antibody solution was added and the flow-through was recovered. The remaining protease was eluted using an elution buffer (50 mM Tris-HCl, 10 mM reduced glutathione, pH 8.0) after the column was washed with PBS. The purified sample was analyzed by SDS-PAGE.
[0288] Results of SDS-PAGE are shown in FIG. 42. As clearly shown from FIG. 42, it could be confirmed that the linker of HER2×HER3 TribsMab CLC of Example 1 was cleaved, and the bispecific antibody of Example 14 was obtained.
[0289] The binding activity evaluation of the linker-cleaved HER2×HER3 TribsMab CLC of Example 14 obtained as described above by flow cytometry to HER2 and HER3-positive human mammary adenocarcinoma cells MCF-7 was performed.
[0290] Using MCF-7 cells cultured in a 10% FBS/DMEM medium, the linker-cleaved HER2×HER3 TribsMab CLC (500 nM) of Example 14 as a primary antibody was reacted with MCF-7 cells for 30 minutes, and then washed twice with 0.1% NaN.sub.3/PBS. Subsequently, 1 μL of an anti-human IgG (Fc-specific)-FITC antibody (Sigma Aldrich) as a secondary antibody and 499 μL of 0.1% NaN.sub.3/PBS were added and reacted for 30 minutes, and then washed twice with 0.1% NaN.sub.3/PBS. Thereafter, the cells were subjected to flow cytometric analysis using BD Accuri™ C6 (BD Biosciences).
[0291] Results are shown in FIG. 43. As clearly shown from FIG. 43, the linker-cleaved HER2×HER3 TribsMab CLC of Example 14 also maintained binding activity.
However, the specification does not teach the structure-identifying information, e.g., amino acid sequences of variable region Va1, variable region Va2, variable region Vb (claims 1, 9) or heavy-chain variable region VHa1, a heavy-chain variable region VHa2 (claim 6) or any single-chain antibody further binds to any variable region Va1 and/or the constant region Ca2, or Vb (claim 8) that correlated with binding about the claimed multispecific antibodies as a pharmaceutical composition. The specification fails to disclose a correlation between structure, e.g., amino acid sequence of the Va1 and Va2, Vb and function, e.g., binding specificity of all multispecific antibodies. There is no limitation on the structure or function of the multispecific antibody, or the epitope to which it binds. One of skill in the art cannot predict which undisclosed multispecific antibody is effective as a pharmaceutical composition (claim 16) for treating which disease.
At the time the invention was made, it was known in the art that antibodies have a large repertoire of distinct structures and that a huge variety of antibodies can be made to bind to a single epitope.
For example, Lloyd et al. taught that hundreds of functional antibody fragments can be isolated from an antibody library that bind to the same antigen wherein these antibodies have distinct heavy and light chain sequences (Lloyd et al. Protein Engineering, Design & Selection 2009, 22:159-168; see, e.g., Discussion).
Similarly, Edwards et al., J Mol Biol. 2003 Nov 14;334(1): 103-118, found that over 1000 antibodies, all different in amino acid sequence, were generated to a single protein; 568 different amino acid sequences identified for the V(H) CDR3 domains of these antibodies (Abstract). Given that hundreds of unique antibody structures may bind a single antigen, the structure of an antibody cannot be predicted from the structure of the antigen, and a single species, or small group of species, cannot define a structure-function relationship so as to be representative of all the antibodies that bind to that antigen.
Given the lack of guidance as to the binding specificity of the multispecific antibody, and the lack of in vivo working examples, it is unpredictable which undisclosed multispecific antibody is effective as a pharmaceutical composition (claim 16) for treating disease such as cancer or diagnostic agent (claim 15).
Regarding peptide linker LL, the specification discloses just protease cleavable peptide linker consisting of the amino acid sequence of SEQ ID NO: 2, 4, 5, 6 and 7 that linked VHa1-CHa1 and VHa2-CHa2 wherein the peptide linker has a particular length in terms of Angstrom, see Table 1.
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However, one species of human rhinovirus 3C (HRV3C) protease recognition sequence LEVLFQGP is not representative of the genus of protease recognition sequences (claims 3-4, 9) and any peptide linker LL having a length between 70 and 280 Angstrom (claim 2).
Thus, the scope of the claims is extremely broad compared to the guidance and exemplification provided in the specification. The scope of the claims must bear a reasonable correlation with the scope of enablement. See In re Fisher, 166 USPQ 19 24 (CCPA 1970). The state of the prior art is such that
Therefore, one skilled in the art cannot practice the invention with a reasonable expectation of success without undue experimentation.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103(a) 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.
This application currently names joint inventors. In considering patentability of the claims under pre-AIA 35 U.S.C. 103(a), the examiner presumes that the subject matter of the various claims was commonly owned at the time any inventions covered therein were made absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and invention dates of each claim that was not commonly owned at the time a later invention was made in order for the examiner to consider the applicability of pre-AIA 35 U.S.C. 103(c) and potential pre-AIA 35 U.S.C. 102(e), (f) or (g) prior art under pre-AIA 35 U.S.C. 103(a).
Claims 1, 3-7, 15 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Gao et al (WO2013006544, published January 10, 2013; PTO 892) in view of de Kruif et al (US20190352401, published November 21, 2019; PTO 892), and Loew et al (US20170368169, published December 28, 2017; PTO 892).
Claim 1 encompasses a multispecific antibody comprising a Fab region that includes one polypeptide a chain below and two polypeptide b chains below:
the polypeptide a chain including a polypeptide in which a variable region Val, a constant region Cal, a peptide linker LL, a variable region Va2, and a constant region Ca2 are linked in the stated order; and
the polypeptide b chain including a polypeptide in which a variable region Vb is linked to a constant region Cb binding to the constant region Cal or the constant region Ca2.
Claim 3 encompasses the multispecific antibody according to claim 1, wherein the peptide linker LL includes a protease recognition sequence.
Claim 4 encompasses the multispecific antibody according to claim 3, wherein the peptide linker LL includes a protease recognition sequence Lrl on the constant region Cal side and a protease recognition sequence Lr2 on the variable region Va2 side.
Claim 5 encompasses the multispecific antibody according to claim 1, wherein the multispecific antibody is IgD, IgE, IgG, or F(ab')2.
Claim 6 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a heavy-chain constant region CHal, a peptide linker LL, a heavy-chain variable region Vla2, and a heavy-chain constant region CHa2 are linked in the stated order.
Claim 7 encompasses the multispecific antibody according to claim 1, wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region VHal, a light-chain constant region CLal, a peptide linker LL, a heavy-chain variable region Vla2, and a light-chain constant region CLa2 are linked in the stated order.
Claim 15 encompasses any diagnostic agent comprising the multispecific antibody according to claim 1.
Claim 16 encompasses a pharmaceutical composition comprising the multispecific antibody according to claim 1.
Regarding claim 1, Gao teaches a multispecific or bispecific IgG antibody (para. [0007], [0014], [0015], [0070] to [0071], Fig 1) monovalent for each antigen (aka Fab region, Fig 1). To overcome the heavy chain-pairing problem, the bispecific IgG antibody is engineered with protease cleavable linkers to connect different domains. For example, the bispecific antibody comprises two light chains and two heavy chains wherein a light chain 1 comprising a light chain variable 1 (VL1, aka instant Va1), a constant region CL1 (aka Ca1), a protease cleavable linker (aka a peptide linker LL) linked to a first heavy chain (aka polypeptide b chain) comprising a first heavy chain variable region VH1 (aka a variable region Vb), a constant region CH1 (aka Cb) binding to the Fc constant region CH2-CH3, a protease cleavable linker, a second light chain 2 comprising a VL2 (aka Va2) and a CL2 (aka Ca2), a protease cleavable linker linked to a second heavy chain 2 (second polypeptide b) comprising a variable domain (aka Vb), a constant CH1 (aka Cb) -CH2-CH3, wherein the CH1 binds to light chain CL1 see Figure 3A and B below.
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Once treated (e.g., with protease) to cleave the linkers, the polypeptide (aka IgG) is no longer a single, contiguous polypeptide chain.
One of the significant advantages is the ability to efficiently produce bispecific antibody (iMers) that, because of the construction of the nucleic acid molecules that encode the relevant polypeptides, do not require extensive, time consuming, laborious purification to remove contaminating homodimeric or other mismatched forms of the desired multimers, see para. [0214].
Regarding claim 3, Gao teaches that the peptide linker comprises at least one protease recognition site to remove the linker, see para. [0100], [0107].
Regarding claim 4, Gao teaches that the peptide linker includes a protease sequence (diamond) on the constant region, e.g., CH1 or CL1 and a protease recognition sequence (diamond) on the variable region, see Figure 3A, in particular. Example of protease recognition sequences include thrombin-sensitive cleavage site (aka Lr1 or Lr2), for example the sequence LVPRGS or VIAGR, see para. [0100].
Regarding claim 5, Gao teaches that the multispecific or bispecific antibody is IgG isotype, see para. [0036], [0051], [0052], IgD or IgE, see para. [0052] or F(ab’)2, see para. [0060].
Regarding claim 15, Gao teaches that the antibody iMers bind to different sites on different target molecule can be used in diagnostic, see para. [0214] to [0215].
Regarding claim 16, Gao teaches pharmaceutical composition comprising the reference bispecific antibody iMers, see para. [0201] to [0202].
Gao does not teach that the linker LL linking the constant domain Ca1 to the Va2 (variable region having different binding specificity) as per claim 1 as shown in Fig 1 below.
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and wherein the polypeptide a chain includes a polypeptide in which a heavy-chain variable region Va1, a heavy-chain constant region CHa1, a peptide linker LL, a heavy-chain variable region VHa2 and a heavy-chain constant region CHa2 are linked in the stated order as per claim 6.
However, de Kruif teaches bispecific full length IgG molecule (see para. [0319]) wherein the binding domain is a Fab domain, for example, of VH-CH1-linker-VH-CH1, wherein the linker connects the heavy chain of the base antibody portion to the at least one additional binding domain, preferably a Fab domain as per claim 6, see para. [0232], Fig 1f, dotted line).
Loew teaches multispecific or bispecific (see entire document, para. [0143] to [0144]) IgG molecule (para. [0148]) CrossMab technology which avoids non-specific L chain mispairing by exchanging CH1 and CL domains in the Fab of one half of the bispecific antibody, resulting the claimed VH-CL, see para. [0502]. The exchange of the CH1 and CL domains ensured that the modified antibody (Antibody A) light chain would only efficiently dimerize with the modified antibody (antibody A) heavy chain, while the unmodified antibody (Antibody B) light chain would only efficiently dimerize with the unmodified antibody (Antibody B) heavy chain; and thus only the desired bispecific CrossMab would be efficiently formed, see para. [0502]. Claim 7 is included because exchanging CH1 domain for CL domain in de Kruif’s VH-CH1-linker-VH-CH1 would result in the claimed polypeptide in which a VHa1-CLa1-linker-VHa2-CLa2.
It would have been prima facie obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to combine the teachings of Gao in view of de Kruif and Loew to have produced the claimed multispecific antibody comprising a Fab region by linking Gao’s first light chain comprising VL1 and CL1 to a second light chain comprising VL2 and CL2 or de Kruif’s first heavy chain comprising VH and a CH1 and a second heavy chain comprising a second VH and a CH1 or Loew’s first heavy chain comprising VH1 and CH1 to a second heavy chain comprising VH2 and CH1 wherein the CH1 domains are exchanged to CL domain using any protease cleavable linker as taught by Gao to arrive at the claimed with a reasonable expectation success, i.e., monovalent multispecific or bispecific IgG antibody having one Fab of one half of the bispecific IgG antibody binds to a first antigen of interest and the other Fab of the half antibody binds to a second antigen of interest. Thus linking various domains, e.g., constant domain to second variable domain with a protease cleavable linker is an obvious variation of the references teachings.
One of ordinary skill in the art would have been motivated to do so because Gao teaches that the peptide linkers comprising protease recognition sequences are known in the art; the use of protease cleavable linker to link various antibody heavy and light chain domains can facilitate the production of multispecific or bispecific antibody IgG and avoiding the extensive, time consuming, laborious purification to remove contaminating homodimeric or other mismatched forms of the desired multimers see para. [0214].
One of ordinary skill in the art would have been motivated, with a reasonable expectation of success to do so, because Loew teaches that exchanging the CH1 with the CL domains in the Fab of one half of the bispecific antibody ensured that the modified antibody (Antibody A) light chain would only efficiently dimerize with the modified antibody (antibody A) heavy chain, while the unmodified antibody (Antibody B) light chain would only efficiently dimerize with the unmodified antibody (Antibody B) heavy chain, see para. [0502].
In addition, the claims would have been obvious because "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and common sense". See KSR International Co. v. Teleflex Inc., 82 USPQ2d 1385 (U.S. 2007).
“The test of obviousness is not express suggestion of the cl aimed invention in any or all of the references but rather what the references taken collectively would suggest to those of ordinary skill in the art presumed to be familiar with them.” See In re Rosselet 146 USPQ 183, 186 (CCPA 1965).
“There is no requirement (under 35 USC 103(a)) that the prior art contain an express suggestion to combine known elements to achieve the claimed invention. Rather, the suggestion to combine may come from the prior art, as filtered through the knowledge of one skilled in the art.,” Motorola, Inc, v. Interdigital Tech. Corn., 43 USPQ2d 1481, 1489 (Fed. Cir. 1997).
Accordingly, the claimed invention as a whole was prima facie obvious to one of ordinary skill in the art before the effective filling date of the claimed invention especially in the absence of evidence to the contrary.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Gao et al (WO2013006544, published January 10, 2013; PTO 892) in view of de Kruif et al (US20190352401, published November 21, 2019; PTO 892), and Loew et al (US20170368169, published December 28, 2017; PTO 892) as applied to claims 1, 3-7, 15 and 16 mentioned above and further in view of Lazar (WO2016164480, published Oct 13, 2016; PTO 892) and Holliger et al (Protein Eng 9(3): 299-305, 1996; PTO 892).
The combine teachings of Gao, de Kruif and Loew have been discussed supra.
The references do not teach multispecific antibody wherein the peptide linker is 70 to 280 Angstrom as per claim 2.
However, Lazar teaches suitable linkers are known in the art and flexible linker of various length such as (Ser-Gly-Gly-Gly-Gly)n (SEQ ID NO:229) wherein n is 15 or 20, see para. [0198]. The polypeptide linker may be used for attachment of an antigen binding region to an Fc region (para. [0197]) or the heavy and light chain variable region, see para. [0195].
The reference polypeptide linker of SEQ ID NO: 229 is 97.9% identical to instant SEQ ID NO: 3, see sequence alignment below:
Query Match 97.9%; Score 380; Length 100;
Best Local Similarity 100.0%;
Matches 68; Conservative 0; Mismatches 0; Indels 0; Gaps 0;
Qy 2 SGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGG 61
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Db 1 SGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGG 60
Qy 62 SGGGGSGG 69
||||||||
Db 61 SGGGGSGG 68
Lazar does not teach said linker is 70 to 280 Å in length.
However, Holliger teaches that diabodies are a class of engineered antibody fragments with two antigen binding sites, consisting of two associated chains; each chain consists of heavy variable domain (VH) and light chain variable domain (VL) linked by a short polypeptide linker, e.g., Gly4Ser. In contrast to IgG, or other antibody fragments in which the two binding sites can take up a range of orientations and spacings, the diabody structure is more rigid and compact, with the two binding sites separated by 65 Å (less than half the distance in IgG, or 130 Å), see abstract, in particular. Holliger further teaches that the complete IgG that span between the centers of the two antigen binding sites is 147 Å but may reach up to 170 Å with the fully stretch Fab arms, see p. 304, left col.
In view of the combined teachings of the references, it would have been prima facie obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to combine the teachings of Gao, de Kruif, Loew in view of Lazar and Holliger to have produced a multispecific or IgG bispecific antibody by substituting the linker of Gao for another, e.g., flexible linker GGGGS of Lazar having a distance of at least 130 Å (twice that of 65 Å) or more such as 170 Å for the full-length IgG antibody comprising Fab region as taught by Holliger to arrive at the claimed peptide linker with a reasonable expectation of success, e.g., linking the N-terminus of polypeptide a heavy chain comprising a VL-CL or VH-CH1 in the first half antibody (first Fab) to the C-terminus of constant domain, e.g., CH1 or CL in the VH-CH1 or VL-CL of the second half antibody (second Fab) to form a three chains IgG bispecific antibody, without byproduct. The reference linker length of 130 Å or 170 Å is within the claimed range of 70 to 280 Å.
One of ordinary skill in the art would have been motivated, with a reasonable expectation of success to do so because Lazar teaches that suitable linkers are known in the art, see p. 49, para. [0198] and Gao teaches that linker to link various antibody heavy and light chain domains can facilitate the production of multispecific or bispecific antibody IgG, without the extensive, time consuming, laborious purification to remove contaminating homodimeric or other mismatched forms of the desired multimers see para. [0214].
In addition, the claims would have been obvious because "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and common sense". See KSR International Co. v. Teleflex Inc., 82 USPQ2d 1385 (U.S. 2007).
“The test of obviousness is not express suggestion of the cl aimed invention in any or all of the references but rather what the references taken collectively would suggest to those of ordinary skill in the art presumed to be familiar with them.” See In re Rosselet 146 USPQ 183, 186 (CCPA 1965).
“There is no requirement (under 35 USC 103(a)) that the prior art contain an express suggestion to combine known elements to achieve the claimed invention. Rather, the suggestion to combine may come from the prior art, as filtered through the knowledge of one skilled in the art.,” Motorola, Inc, v. Interdigital Tech. Corn., 43 USPQ2d 1481, 1489 (Fed. Cir. 1997).
Accordingly, the claimed invention as a whole was prima facie obvious to one of ordinary skill in the art before the effective filling date of the claimed invention especially in the absence of evidence to the contrary.
CLAIM INTERPRETATION
Claim 8 is interpreted to mean the multispecific antibody of claim 1 further comprises a single-chain antibody linked to the variable region Va1 and/or the constant region Ca2.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Gao et al (WO2013006544, published January 10, 2013; PTO 892) in view of de Kruif et al (US20190352401, published November 21, 2019; PTO 892), and Loew et al (US20170368169, published December 28, 2017; PTO 892) as applied to claims 1, 3-7, 15 and 16 mentioned above and further in view of Sabzevari (WO2016115274, published July 21, 2016; PTO 892) and/or Berett et al (WO2018045110, published March 8, 2018; PTO 892).
The combine teachings of Gao, de Kruif and Loew have been discussed supra.
The references do not teach multispecific antibody further comprises a single-chain antibody linked to the variable region Va1 and/or the constant region Ca2 as per claim 8.
However, the Sabzevari teaches multispecific immunomodulatory antigen-binding construct (MIAC or instant IgG antibody) comprising single chain antibody (scFv, 202 and 203) is linked to the C-terminus of the IgG light chain constant region (aka ca2), see para. [0016], [0023], [0057], [0017], see FIG. 2B.
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.
Sabzevari does not teach scFv antibody is linked to the variable region of the multispecific IgG antibody.
However, WO 2018045110 publication teaches bispecific antibody, e.g., scFv-mAb comprising scFv that binds to antigen 2 is linked to the N-terminus of the VH domain of a Fab that binds to antigen-1, see para. [0019], [00260], Figure 2E below:
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This structure is sometimes referred to herein as "triple f" format (scfv-fab-f c) or the "bottle-opener" format, due to a rough visual similarity to a bottle-opener (see Figure 2). The two chains are brought together by the use of amino acid variants in the constant regions (e.g. the Fc domain and/or the hinge region) that promote the formation of heterodimeric antibodies as is described more fully below, see para. [00145]. As is known in the art, antibody analogs relying on two scFv constructs often have stability and aggregation problems, which can be alleviated in the present invention by the addition of a "regular" heavy and light chain pairing. In addition, as opposed to formats that rely on two heavy chains and two light chains, there is no issue with the incorrect pairing of heavy and light chains (e.g. heavy 1 pairing with light 2, etc.), see para. [00146].
It would have been prima facie obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to combine the teachings of Gao, de Kruif and Loew in view of Sabzevari and/or Bernett to have produced multispecific IgG antibody by linking any scFv antibody to the N-terminus of the VH or VL domain of the Fab arm of IgG as taught by Bernett and/or linking any scFv to the C-terminus domain of the IgG light chain constant region as taught by Sabzevari to arrive at the claimed invention with a reasonable expectation of success, e.g., formation of trispecific or tetraspecific antibody.
One of ordinary skill in the art would have been motivated to do so because Sabzevari teaches that single chain antibody (scFv, 202 and 203) can be linked to the C-terminus of the IgG light chain constant region (aka ca2) and Bernett teaches that linking scFv antibody to light chain constant region can alleviate aggregation problems of scFv and improved stability, see para. [00146].
One of ordinary skill in the art would have been motivated, with a reasonable expectation of success to do so because Bernett teaches that there is no issue with the incorrect pairing of heavy and light chains (e.g. heavy 1 pairing with light 2, etc.), see para. [00146].
In addition, the claims would have been obvious because "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and common sense". See KSR International Co. v. Teleflex Inc., 82 USPQ2d 1385 (U.S. 2007).
“The test of obviousness is not express suggestion of the cl aimed invention in any or all of the references but rather what the references taken collectively would suggest to those of ordinary skill in the art presumed to be familiar with them.” See In re Rosselet 146 USPQ 183, 186 (CCPA 1965).
“There is no requirement (under 35 USC 103(a)) that the prior art contain an express suggestion to combine known elements to achieve the claimed invention. Rather, the suggestion to combine may come from the prior art, as filtered through the knowledge of one skilled in the art.,” Motorola, Inc, v. Interdigital Tech. Corn., 43 USPQ2d 1481, 1489 (Fed. Cir. 1997).
Accordingly, the claimed invention as a whole was prima facie obvious to one of ordinary skill in the art before the effective filling date of the claimed invention especially in the absence of evidence to the contrary.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 9 is rejected under 35 U.S.C. 102 (a)(1) as being anticipated by Brinkmann et al (US20130266568, published Oct 10, 2013; PTO 892).
Brinkmann teaches a bispecific antibody comprising a Fab region, e.g., VH-CH1 paired with VL-CL, having four polypeptides wherein the first polypeptide a’ chain comprising VL-CL, a peptide linker with protease cleavage site and VL’-CL. The term “including” is open ended. It expands the a’ chain to include additional Fab comprising VL’-CL. The second polypeptide a’’ comprising VL-CL, a peptide linker with protease cleavage site and VL’-CL. The third and fourth polypeptide b chain each comprises a VH2-CH1, a peptide linker without protease cleavage site, a VH1-CH1, a CH2-CH3 wherein the CH1 binds to the CL, see Figure 2d below:
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The term “including” is open ended. It expands the b chain to include additional domains. Thus, the reference teachings anticipate the claimed invention.
Conclusion
Peptide linker (LL) consisting of the amino acid sequence of SEQ ID NO: 2, 4, 5, 6 or 7 is free of prior art.
No claim is allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PHUONG HUYNH whose telephone number is (571)272-0846. The examiner can normally be reached on 9:00 a.m. to 6:30 p.m. The examiner can also be reached on alternate alternative Friday from 9:00 a.m. to 5:30 p.m.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Misook Yu, can be reached at 571-270-3497. The fax phone number for the organization where this application or proceeding is assigned is 571-272-0839.
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/PHUONG HUYNH/ Primary Examiner, Art Unit 1641