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 .
Claims 1-21 are pending.
Applicant’s election without traverse of Group I in the reply filed on May 27, 2025 is acknowledged.
Claims 15-18 are withdrawn from further consideration by the examiner, 37 C.F.R. 1.142(b) as being drawn to non-elected inventions.
Claims 1-14 and 19-21, drawn to an isolated dimer comprising a first polypeptide and a second polypeptide, each polypeptide comprising a human IgG Fc region comprising a variant CH2 domain each variant CH2 domain comprising a L234A amino acid substitution, a L235A amino acid substitution, and a D265S amino acid substitution, wherein the amino acid positions are numbered according to the EU index of Kabat, are being acted upon in this Office Action.
Priority
Applicant’ claim priority to provisional applications 61/845,948 filed July 12, 2013 and 61/671,640 filed July 13, 2012, is acknowledged.
Applicant’s claim for the benefit of a prior-filed application under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, or 365(c) is acknowledged. Applicant has not complied with one or more conditions for receiving the benefit of an earlier filing date under 35 U.S.C. 120 as follows:
The later-filed application must be an application for a patent for an invention which is also disclosed in the prior application (the parent or original nonprovisional application or provisional application). The disclosure of the invention in the parent application and in the later-filed application must be sufficient to comply with the requirements of the first paragraph of 35 U.S.C. 112. See Transco Products, Inc. v. Performance Contracting, Inc., 38 F.3d 551, 32 USPQ2d 1077 (Fed. Cir. 1994).
The disclosure of the prior-filed application 61/671,640 fails to provide adequate support or enablement in the manner provided by the first paragraph of 35 U.S.C. 112 for one or more claims of this application. The provisional application 61/671,640 does not disclose the particular substitutions L234A, L235A, D265S as recited in claim 1, T350V, L351Y, F405A and Y407V as recited in claim 6, T350V, T366L, K392L and T394W as recited in claim 6.
Therefore for the purposes of applying prior art, the effective filing date of claims 1-14 and 19-21 is July 12, 2013, the date that provisional application 61/845,948 was filed.
Should applicant disagree with the examiner’s factual determination above, applicant should point to evidence that shows that the invention of claims 1-14 and 19-21 is in fact described in one or more of the previously-filed applications.
Information Disclosure Statement
The information disclosure statements (IDS) submitted July 9, 2024 have been considered by the examiner and an initialed copy of the IDS is included with this Office Action.
Drawings
The drawings were received on March 21, 2024. These drawings are acceptable.
Specification
The substitute specification filed on July 5, 2024 has been entered.
Applicants should amend the first line of the specification to update the relationship between the instant application, U.S. Application No. 17/207,506, file March 19, 2021, now abandoned, U.S. Application No. 16/256,824, filed January 24, 2019, now abandoned, and U.S. Application No. 13/941,449, filed July 13, 2013, now abandoned.
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 rejections under - 35 U.S.C. 112
The following is a quotation of the first paragraph 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 the first paragraph of pre-AIA 35 U.S.C. 112:
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 1-14 and 19-21 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.
MPEP § 2163 states that 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 and/or 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 the applicant was in possession of the claimed genus.
Claim 1 encompasses any isolated dimer comprising a first polypeptide and a second polypeptide, each polypeptide comprising a human IgG Fc region comprising a variant CH2 domain, each variant CH2 domain comprising a L234A amino acid substitution, a L235A amino acid substitution, and a D265S amino acid substitution, wherein the amino acid positions are numbered according to the EU index of Kabat.
Claim 2 encompasses the isolated dimer of claim 1, wherein at least one of the first and second polypeptides further comprises an antigen-binding domain.
Claim 3 encompasses the isolated dimer of claim 2, wherein the antigen-binding domain comprises an scFv.
Claim 4 encompasses the isolated dimer of claim 2, wherein the antigen-binding domain comprises a Fab.
Claim 5 encompasses the isolated dimer of claim 1, wherein one of the first and second polypeptides further comprises an scFv and the other of the polypeptides further comprises a Fab.
Claim 6 encompasses the isolated dimer of claim 1, wherein one of the first and second polypeptides further comprises amino acid substitutions T350V, L351Y, F405A, and Y407V, and the other of the polypeptides further comprises amino acid substitutions T350V, T366L, K392L, and T394W.
Claim 7 encompasses the isolated dimer of claim 1, wherein the IgG is an IgG1.
Claim 8 encompasses any antibody comprising the isolated dimer of claim 1.
Claim 9 encompasses the e antibody of claim 8, wherein the antibody is any monoclonal antibody, any humanized antibody, or any human antibody.
Claim 10 encompasses the antibody of claim 8, wherein the antibody is multispecific.
Claim 11 encompasses the antibody of claim 8, wherein the antibody is bispecific.
Claim 12 encompasses the isolated dimer of claim 1, wherein the dimer is a heterodimer.
Claim 13 encompasses a pharmaceutical composition comprising the isolated dimer of claim 1 and a pharmaceutically acceptable carrier.
Claim 14 encompasses a pharmaceutical composition comprising the antibody of claim 8 and a pharmaceutically acceptable carrier.
Claim 19 encompasses the isolated dimer of claim 12, wherein each of the first and second polypeptides further comprises an antigen-binding domain.
Claim 20 encompasses the isolated dimer of claim 19, wherein each antigen-binding domain binds a different antigen.
Claim 21 encompasses the isolated dimer of claim 20, wherein one of the antigen-binding domains binds to a CD3 complex.
The specification discloses heterodimer:
[0359] v4541 has an anti-CD3 BiTE™ (VH-VL) 44-100SS scFv on chain A and anti-CD19 BiTE™ (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 50 and 52] Cyno/Human Cross-Reactive Anti-CD3 and Anti-CD19 Bispecific Fc Knock-Out Variants with or without Disulfide 44-100 Stabilization
[0360] v4542 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VH-VL) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 54 and 56].
[0361] v4543 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VH-VL) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 58 and 60]
[0362] v4544 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 62 and 64]
[0363] v4545 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VL-VH) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 66 and 68]
[0364] v4546 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VH-VL) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 70 and 72]
[0365] v4547 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VH-VL) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 74 and 76].
[0366] v4548 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 78 and 80] v4549 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VL-VH) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 82 and 84]
Regarding multispecific antibody, the specification discloses:
Example 3: Heteromultimer v873 is Able to Bridge Jurkat CD3 T Cells and Raji CD19 B Cells
Example 4: Heteromultimers Bind Selectively to CD3- and CD19-Expressing Cells
[0384] The ability of an exemplary heteromultimer, v873, to bind specifically to CD3 and CD19 was assessed by FACS. One-armed antibodies (OAAs) against CD3 and CD19 were also prepared as described in Example 2 and tested as controls in the whole cell FACS binding assay described below.
Example 5: Heteromultimers Mediate PBMC Killing of Target Raji B Cells
Example 6: Heteromultimers Mediate Redirected Killing of Target Raji B Cells with Resting and IL-2 Activated CD4+ and CD8+ T Cells
[0405] The ability of an exemplary heteromultimers, v875, v1379, v1380 to mediate CD4+ and CD8+ T cell cytoxicity against target Raji B-cells was measured as described in Example 5.
Example 7: The Heterodimeric Fc Contributes to Target Raji B Cell Cytotoxicity
[0410] The ability of exemplary heteromultimers, v875, and v873, to mediate target Raji B-cell cytotoxicity in the presence and absence of Fc was measured as described in Example 5.
Example 8: Heteromultimers Mediate Autologous B Cell Cytotoxicity
[0413] The ability of exemplary the heteromultimer v875 and v873 to kill autologous B-cells was measured in total and resting IL-2-stimulated PBMCs where the percent of CD19+ 7AAD+ cells following incubation with v875 and v873 (300 nM, n=3 donors) was determined by flow cytometry as described in Example 5.
Example 9: Heteromultimer v875 Spares Autologous T Cell Cytotoxicity Compared to BiTE
[0415] The effects of exemplary heteromultimer v875 and v873 treatment on the autologous T cell population was assessed in total and resting IL-2-stimulated PBMCs where the percent of CD3+ 7AAD+ cells following incubation with v875 and v873 (300 nM, n=3 donors) was determined by flow cytometry as described in Example 5.
[0416] FIG. 22 shows, relative to untreated media and human IgG controls, v875 has a more selective B cell killing by sparing more autologous T cells compared to v873 and v891.
Example 10: Design, Expression and Purification of Heteromultimers with an Albumin Scaffold
[0417] The following exemplary CD3-CD19 binding heteromultimers based on an albumin scaffold were designed and prepared as follows.
[0418] The sequences for the anti-CD19 and anti-CD3 scFvs were chosen from two molecules that are currently in clinical trials and are well documented and tested for stability and production. The anti-CD19 and anti-CD3 scFv were directly adopted from the BiTE molecule blinatumomab. The antiCD3 scFv was chosen in the VH-VL orientation, consistent with what used in BiTE. The benchmark molecule was an scFv molecule based on BiTE (v891). AlbuCORE_1 (ABH2) CD3/CD19 fusions were created by attaching the antiCD3 warhead to the natural N terminus of fragment 1 and the antiCD19 to the C terminus of fragment 2 (v1092, polypeptide sequences corresponding to SEQ ID NO:264 and 266). The linkers used were identical to the ones used for the multivalent HER2 AlbuCORE experiments: GGGS (SEQ ID NO: 278) at the N terminus of fragment 1 and (GGSG) 4GG (SEQ ID NO: 279) at the C terminus of fragment 2. A second molecule was created where the warheads were reversed (i.e. anti-CD19 warhead at the natural N terminus of fragment 1 and the anti-CD3 at the C terminus of fragment 2, v1093. v1094 was designed to accommodate two different fusions at the natural termini of the albumin polypeptide (polypeptide sequences corresponding to SEQ ID NO:268). The scFv fusions were linked to the albumin molecule through a GGS linker at the N terminus and a GGSG (SEQ ID NO: 280) linker at the C terminus. The length of the linkers reflect the ones used in the MM-111 molecule, despite having a different sequence type.
Example 11: Heteromultimers with an Albumin Scaffold Bind Specifically to CD3- or CD19-Expressing Cells
[0421] The ability of Anti-CD3×CD19 loaded AlbuCORE-1 (v1092) to CD3+ and CD19+ cells was assessed using FACS and compared to WT-HSA loaded with the same anti-CD scFvs (v1094).
[0422] The results are shown in FIG. 4 and demonstrate that both v1092 and v1094 are able to bind to CD3-expressing Jurkat T-cells and to CD19-expressing Raji B-cells.
Example 12: Heteromultimers with Heterodimeric Fc or Albumin Scaffolds Show Comparable B-Cell Targeting and T-Cell Bridging
Example 13: Exemplary Heteromultimers have Higher Anti-CD3 K.SUB.D .and Higher Bmax in Binding to T and B Cell as Determined by FACS
Example 14: Heteromultimer v875 is Able to Bridge Jurkat CD3 T Cells and Raji CD19 B Cells
Example 15: Bridging of B and T Cells by Heteromultimers is Robust at Varying Antibody Concentrations or Cell Ratios
Example 16: Bridging of B and T Cells is Robust Across Differently Engineered Heteromultimers Constructs
Example 17: Effects of v875, v1380, v1379 on IL-2 Activated and Resting CD20+, CD4+, CD8+Subsets
Example 18: Exemplary Heteromultimers v875 and v873 Require the Presence of Both Effector T Cell and Target B Cells to Mediate Cytotoxic Effects
Example 19: Exemplary Heteromultimers can Mediate ADCC or Impaired ADCC to Target Daudi B Cells
[0444] Antibody-dependent cell-mediated cytotoxicity assays (ADCC) were performed with v875, v1379 and v1380 using Daudi cells as target B cells and FcRy3a immobilized NK92 cells as the effector cells (GS193761) by the following method.
Example 20: Exemplary Heteromultimers have Impaired CDC-Mediated Lysis of Daudi B Cells
[0449] Cell based complement dependent cytotoxicity assays (CDC) were performed with v875, v1379 and v1380 using Daudi cells as target B cells. Human serum from healthy donors (NHS) was used as the source of complement. 10 μl NHS (10% final concentration in 40 reaction volume) were added to each well to initiate the CDC cascade and incubated for 2 hours. Cell viability was measured with CellTiter-Glo@ Luminescent Cell Viability Assay Kit.
Example 21: Cell Proliferation and Cytokine Release Assessment of Exemplary Heteromultimers
Example 22: Exemplary Heteromultimers can Bridge Two or More Target B Cells Per Effector T Cell
[0465] The ability and ratio of numbers of T cell bridged to B cells was examined with the exemplary heteromultimer v875 by microscopy using the method described in Example 3 with the following modifications.
[0466] Labeled Raji B cells (red) and labeled Jurkat T cells (blue) were incubated for 30 min at RT with 3 nM of human IgG or v875. The cell suspension was concentrated by removing 180 μl of supernatant. Cell were resuspended in the remaining volume and imaged at 200× and 400×.
[0467] FIG. 30 shows the results from the T:B cell bridging microscopy comparing v875 and human IgG (3 nM) at 200× and 400× magnification; the phase image (top panel), fluorescence image (middle panel) and inverted fluorescence (bottom panel) are presented. FIG. 30A shows a direct comparison of human IgG and v875 at 200× magnification and illustrates a higher amount of bridging visible between Raji B cell and Jurkat T cells compared to human IgG. FIG. 30B and FIG. 30C show two fields of view for v875 (FIG. 30B) and human IgG (FIG. 30C) at 400× magnification. FIG. 30B shows images of v875-mediated immune complex formation between Jurkat T cells (dark grey cells in fluorescence inverted image) and Raji B cells (light grey cells in fluorescence inverted image), and that one Jurkat T cell can bridge 1-3 Raji B cells. FIG. 30C shows images following human IgG incubation with Jurkat T cells and Raji B cells. FIG. 30C shows an absence of the Jurkat-Raji bridging following incubation with human IgG, compared to the v875-mediated Jurkat: Raji bridging that is visible in FIG. 30B.
Example 23: Exemplary Heteromultimer Binding to Fcγ Receptors as Assessed by Surface Plasmon Resonance
Example 25: Expression and Purification of Heteromultimers
[0476] Description of the methods used in the expression and purification of exemplary heteromultimer are described in Example 2.
Example 26: Exemplary Heteromultimers can be Purified to >99% Heterodimer Purity and <1% Aggregates
Example 27: Exemplary Heteromultimers have a CH3 Tm that is Greater than 75° C.
[0487] CH3 domain stability of exemplary heteromultimers was examined by DSC using the following method. All DSC experiments were carried out using a GE VP-Capillary instrument. The proteins were buffer-exchanged into PBS (pH 7.4) and diluted to 0.3 to 0.7 mg/mL with 0.137 mL loaded into the sample cell and measured with a scan rate of 1° C./min from 20 to 100° C. Data was analyzed using the Origin software (GE Healthcare) with the PBS buffer background subtracted.
[0488] The DSC results shown in FIGS. 33A, B and C show that v875 has an estimated CH3 Tm >76° C. (FIG. 33A), v1380 has an estimated CH3 Tm >82.3° C. (FIG. 33B), and v1379 has an estimated CH3 Tm >82.5° C. (FIG. 33C).
Example 28: Design, Expression and Purification of CD3/CD20 and Additional CD3/CD19 Heteromultimer Constructs
[0489] V5850 (corresponding to polypeptide sequences SEQ ID NOs: 203, 205 and 207), v5851 (corresponding to polypeptide sequences SEQ ID NOs: 209, 211 and 213), v5852 (corresponding to polypeptide sequences SEQ ID NOs: 215, 217 and 219), v6324 (corresponding to polypeptide sequences SEQ ID NOs: 221 and 223), v6325 (corresponding to polypeptide sequences SEQ ID NOs: 225, 227 and 229), v1813 (corresponding to polypeptide sequences SEQ ID NOs: 231, 233 and 235), v1821 (corresponding to polypeptide sequences SEQ ID NOs: 237, 239 and 241), v1823 (corresponding to polypeptide sequences SEQ ID NOs: 243, 245 and 247) exemplify bispecific CD3/CD19 or CD3/CD20 hybrid heterodimeric Fc constructs. Bispecific hybrid variants are composed of a F(ab′) on either chain A or B paired with an scFv-Fc on the alternate polypeptide chain. Chain A of the heterodimer Fc is comprised of the following mutations: T350V_L351Y_F405A_Y407V and Chain B of the heterodimer Fc is comprised of the following mutations: T350V_T366L_K392L_T394W. v6324 exemplifies bispecific CD3/CD20 scFv heterodimeric Fc constructs. V1813, v1821, and v1823 exemplify CD3/CD20 common light chain heterodimeric Fc constructs. Common light chain variants are composed of two different F(ab′) s, each on complimentary heterodimer Fc, which share a single light chain. The specific variant composition is indicated in Table 7.
However, the disclosure of just heterodimer is not representative of all dimer, e.g., homodimer or heterodimer comprises a first human IgG Fc and a second human IgG Fc wherein each Fc comprises a D265S, a L234A and L235A.
Regarding antibody, the specification does not describe the structure, e.g., amino acid sequence of the heavy and light chain variable region of all antigen-binding domain, e.g., any scFv (claim 3), Fab (claim 4), antibody (claim 8), (humanized or human or monoclonal antibody (claim 9), multispecific antibody (claim 10) or bispecific antibody (claim 11) that correlated with binding to any and all different antigen (claim 20) and all CD3 complex (claim 21) and pharmaceutical composition (claims 13-14) to enable one of skilled in the art to visualize or recognize the member of the genus of the actual claimed dimer and antibody themselves. The specification does not describe a representative number of species of dimer or antibody as a pharmaceutical composition for treating which disease. The specification does not describe the structure correlated with binding falling within the scope of the genus or structural common to the members of the genus so the one of skill in the art can visualize or recognize the member of the genus. An adequate written description must contain enough information about the actual makeup of the claimed products – “a precise definition, such as structure, formula, chemic name, physical properties of other properties, of species falling with the genus sufficient to distinguish the gene from other materials”, which may be present in “functional terminology when the art has established a correlation between structure and function” (Amgen page 1361).
Notably, the specification, does not describe the structure, e.g., amino acid sequence of the heavy and light chain variable domains or the six CDRs that correlated with binding to any antigen (claim 20) and any CD3 complex (claim 21). There is no limitation on the structure and the antigen to which it binds.
At the time of the invention was made, it is 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, PTO 1449; see, e.g., Discussion).
Similarly, Edwards et al., (J Mol Biol. 334(1): 103-118, 2003; PTO 1449), 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).
Poosarla et al (Biotechn. Bioeng., 114(6): 1331-1342, 2017; PTO 892) teach substantial diversity in designed mAbs (sharing less than 75% sequence similarity to all existing natural antibody sequences) that bind to the same 12-mer peptide, binding to different epitopes on the same peptide. Said reference further teaches “most B-cell epitopes... in nature consist of residues from different regions of the sequence and are discontinuous...de novo antibody designs against discontinuous epitopes present additional challenge.
Even assuming the antibody binds to CD3, Shepard et al (PLOSOne 18(6): e0273884, June 22, 2023; PTO 892) teach the unpredictability of swapping CD3 binding domains in the context of a BiTE in so far as the binding requirement to CD3 epsilon much less the extracellular epitope:
“We next sought to test our platform for flexibility with respect to screening novel T-cell engaging domains of the bispecific molecule. We developed a number of novel mouse monoclonal antibodies (mAbs) against human CD3 complex using a multi-antigen immunization strategy in mice and traditional hybridoma screening. Through this process, we were able to identify several monoclonal antibodies with reactivity to Jurkat cells (Fig 4A) and human T cells (Fig 4B). To assess whether scFvs derived from novel CD3-targeted mAbs would be functional within as part of a BiTE molecule, we cloned 4 anti-human CD3 single chain variable fragments into CD19 or EGFRvIII specific BiTE plasmids (Fig 4C). We then generated supernatants using transient transfection of HEK293T as described above. BiTE supernatants were screened for activity using Jurkat cells in co-culture with EGFRvIII-expressing U87-VIII targets or CD19-expressing Raji cells. Previously tested constructs using OKT3 CD3-engager arms showed activity with both EGFRvIII and CD19 specific BiTEs, whereas we detected activity for only one of our novel CD3-engager BiTEs and only when combined with an EGFRvIII-specific scFv (Fig 4D). To confirm these results, we repeated BiTE production and Jurkat co-culture screening of CD19 and EGFRvIII targeted BiTE molecules incorporating OKT3 or the novel 1E2 CD3-targeting single chain variable fragment. Whereas EGFRvIII BiTEs incorporating an scFv derived from the 1E2 mAb or OKT3 showed specific reactivity against EGFRvIII expressing U87-vIII cells, only CD19-OKT3 showed reactivity to CD19-expressing Raji cells (Fig 4E). These results indicate that the novel CD3-targeting 1E2-scFv is functional only for an EGFRvIII-targeting BiTE but not a CD19-targeting BiTE, likely due to the specific binding characteristics of the CD19 or EGFRvIII scFv elements.”
“Similarly, we also find that only one of the novel CD3-targeting scFvs tested here showed activity in BiTE format, and even then, activity was restricted to combination with EGFRvIII-targeting scFv and not with a CD19-specific scFv. Again, we have no insight into the failure rate for BiTE molecules in this assay, as the intent of this assay is to provide a rapid means for testing biological activity rather than focusing on various aspects of antibody characterization. We are currently undertaking molecular studies to test whether incorporating different linker domains may be able to improve the activity of BiTEs using the novel CD3-scFv reported to have activity here, something that may provide further insight into the design constraints for these BiTE molecules.”
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).
Although one of skill in the art could make a mAb against an antigen/CD3 complex by screening a human antibody phage display library, test candidates, and produce a corresponding antibody, note that: “Possession may not be shown by merely describing how to obtain possession of members of the claimed genus or how to identify their common structural features.” See University of Rochester, 358 F.3d at 927, 69 USPQ2d at 1895.
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 a bispecific CD19 and CD3 scFvs fused to an asymmetric IgG1 heterodimer comprising a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising a human CH2 domain, each CH2 domain comprises a L234A amino acid substitution, a L235A amino acid substitution and a D265S amino acid substitution, wherein the amino acid positions are numbered according to the EU index of Kabat, wherein the first and second polypeptides comprise the amino acid sequences selected from the group consisting of SEQ ID NO: 38 and SEQ ID NO: 40, SEQ ID NO: 42 and SEQ ID NO: 44, SEQ ID NO: 46 and SEQ ID NO: 48, SEQ ID NO: 66 and SEQ NO: 68, SEQ ID NO: 70 and SEQ NO: 72, SEQ ID NO: 74 and SEQ NO: 76, SEQ ID NO: 78 and SEQ NO: 80, SEQ ID NO: 82 and SEQ NO: 84, SEQ ID NO: 133 and SEQ ID NO: 134, SEQ ID NO: 137 and SEQ ID NO: 138, and SEQ ID NO: 141 and SEQ ID NO: 142, 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 1-14 and 19-21 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 a bispecific CD19 and CD3 scFvs fused to an asymmetric IgG1 heterodimer comprising a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising a human CH2 domain, each CH2 domain comprises a L234A amino acid substitution, a L235A amino acid substitution and a D265S amino acid substitution, wherein the amino acid positions are numbered according to the EU index of Kabat, wherein the first and second polypeptides comprise the amino acid sequences selected from the group consisting of SEQ ID NO: 38 and SEQ ID NO: 40, SEQ ID NO: 42 and SEQ ID NO: 44, SEQ ID NO: 46 and SEQ ID NO: 48, SEQ ID NO: 66 and SEQ NO: 68, SEQ ID NO: 70 and SEQ NO: 72, SEQ ID NO: 74 and SEQ NO: 76, SEQ ID NO: 78 and SEQ NO: 80, SEQ ID NO: 82 and SEQ NO: 84, SEQ ID NO: 133 and SEQ ID NO: 134, SEQ ID NO: 137 and SEQ ID NO: 138, and SEQ ID NO: 141 and SEQ ID NO: 142, does not reasonably provide enablement for the isolated dimer set forth in claims 1-14 and 19-21. 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/use the invention commensurate in scope with these claims.
Claim 1 encompasses any isolated dimer comprising a first polypeptide and a second polypeptide, each polypeptide comprising a human IgG Fc region comprising a variant CH2 domain, each variant CH2 domain comprising a L234A amino acid substitution, a L235A amino acid substitution, and a D265S amino acid substitution, wherein the amino acid positions are numbered according to the EU index of Kabat.
Claim 2 encompasses the isolated dimer of claim 1, wherein at least one of the first and second polypeptides further comprises an antigen-binding domain.
Claim 3 encompasses the isolated dimer of claim 2, wherein the antigen-binding domain comprises an scFv.
Claim 4 encompasses the isolated dimer of claim 2, wherein the antigen-binding domain comprises a Fab.
Claim 5 encompasses the isolated dimer of claim 1, wherein one of the first and second polypeptides further comprises an scFv and the other of the polypeptides further comprises a Fab.
Claim 6 encompasses the isolated dimer of claim 1, wherein one of the first and second polypeptides further comprises amino acid substitutions T350V, L351Y, F405A, and Y407V, and the other of the polypeptides further comprises amino acid substitutions T350V, T366L, K392L, and T394W.
Claim 7 encompasses the isolated dimer of claim 1, wherein the IgG is an IgG1.
Claim 8 encompasses any antibody comprising the isolated dimer of claim 1.
Claim 9 encompasses the e antibody of claim 8, wherein the antibody is any monoclonal antibody, any humanized antibody, or any human antibody.
Claim 10 encompasses the antibody of claim 8, wherein the antibody is multispecific.
Claim 11 encompasses the antibody of claim 8, wherein the antibody is bispecific.
Claim 12 encompasses the isolated dimer of claim 1, wherein the dimer is a heterodimer.
Claim 13 encompasses a pharmaceutical composition comprising the isolated dimer of claim 1 and a pharmaceutically acceptable carrier.
Claim 14 encompasses a pharmaceutical composition comprising the antibody of claim 8 and a pharmaceutically acceptable carrier.
Claim 19 encompasses the isolated dimer of claim 12, wherein each of the first and second polypeptides further comprises an antigen-binding domain.
Claim 20 encompasses the isolated dimer of claim 19, wherein each antigen-binding domain binds a different antigen.
Claim 21 encompasses the isolated dimer of claim 20, wherein one of the antigen-binding domains binds to a CD3 complex.
The specification discloses heterodimer:
[0359] v4541 has an anti-CD3 BiTE™ (VH-VL) 44-100SS scFv on chain A and anti-CD19 BiTE™ (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 50 and 52] Cyno/Human Cross-Reactive Anti-CD3 and Anti-CD19 Bispecific Fc Knock-Out Variants with or without Disulfide 44-100 Stabilization
[0360] v4542 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VH-VL) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 54 and 56].
[0361] v4543 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VH-VL) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 58 and 60]
[0362] v4544 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 62 and 64]
[0363] v4545 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MOR208 (VL-VH) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 66 and 68]
[0364] v4546 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VH-VL) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 70 and 72]
[0365] v4547 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VH-VL) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 74 and 76].
[0366] v4548 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VL-VH) scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 78 and 80] v4549 has a cyno/human cross-reactive anti-CD3 BiTE™ 12C (VH-VL) 44-100SS scFv on chain A and cyno/human cross-reactive anti-CD19 MDX-1342 (VL-VH) 44-100SS scFv on chain B of the heterodimer Fc with the following mutations D265S_L234A_L235A_T350V_L351Y_F405A_Y407V on chain A and D265S_L234A_L235A_T350V_T366L_K392L_T394W on chain B. [Polypeptide sequences correspond to SEQ ID No: 82 and 84]
Regarding multispecific antibody, the specification discloses:
Example 3: Heteromultimer v873 is Able to Bridge Jurkat CD3 T Cells and Raji CD19 B Cells
Example 4: Heteromultimers Bind Selectively to CD3- and CD19-Expressing Cells
[0384] The ability of an exemplary heteromultimer, v873, to bind specifically to CD3 and CD19 was assessed by FACS. One-armed antibodies (OAAs) against CD3 and CD19 were also prepared as described in Example 2 and tested as controls in the whole cell FACS binding assay described below.
Example 5: Heteromultimers Mediate PBMC Killing of Target Raji B Cells
Example 6: Heteromultimers Mediate Redirected Killing of Target Raji B Cells with Resting and IL-2 Activated CD4+ and CD8+ T Cells
[0405] The ability of an exemplary heteromultimers, v875, v1379, v1380 to mediate CD4+ and CD8+ T cell cytoxicity against target Raji B-cells was measured as described in Example 5.
Example 7: The Heterodimeric Fc Contributes to Target Raji B Cell Cytotoxicity
[0410] The ability of exemplary heteromultimers, v875, and v873, to mediate target Raji B-cell cytotoxicity in the presence and absence of Fc was measured as described in Example 5.
Example 8: Heteromultimers Mediate Autologous B Cell Cytotoxicity
[0413] The ability of exemplary the heteromultimer v875 and v873 to kill autologous B-cells was measured in total and resting IL-2-stimulated PBMCs where the percent of CD19+ 7AAD+ cells following incubation with v875 and v873 (300 nM, n=3 donors) was determined by flow cytometry as described in Example 5.
Example 9: Heteromultimer v875 Spares Autologous T Cell Cytotoxicity Compared to BiTE
[0415] The effects of exemplary heteromultimer v875 and v873 treatment on the autologous T cell population was assessed in total and resting IL-2-stimulated PBMCs where the percent of CD3+ 7AAD+ cells following incubation with v875 and v873 (300 nM, n=3 donors) was determined by flow cytometry as described in Example 5.
[0416] FIG. 22 shows, relative to untreated media and human IgG controls, v875 has a more selective B cell killing by sparing more autologous T cells compared to v873 and v891.
Example 10: Design, Expression and Purification of Heteromultimers with an Albumin Scaffold
[0417] The following exemplary CD3-CD19 binding heteromultimers based on an albumin scaffold were designed and prepared as follows.
[0418] The sequences for the anti-CD19 and anti-CD3 scFvs were chosen from two molecules that are currently in clinical trials and are well documented and tested for stability and production. The anti-CD19 and anti-CD3 scFv were directly adopted from the BiTE molecule blinatumomab. The antiCD3 scFv was chosen in the VH-VL orientation, consistent with what used in BiTE. The benchmark molecule was an scFv molecule based on BiTE (v891). AlbuCORE_1 (ABH2) CD3/CD19 fusions were created by attaching the antiCD3 warhead to the natural N terminus of fragment 1 and the antiCD19 to the C terminus of fragment 2 (v1092, polypeptide sequences corresponding to SEQ ID NO:264 and 266). The linkers used were identical to the ones used for the multivalent HER2 AlbuCORE experiments: GGGS (SEQ ID NO: 278) at the N terminus of fragment 1 and (GGSG) 4GG (SEQ ID NO: 279) at the C terminus of fragment 2. A second molecule was created where the warheads were reversed (i.e. anti-CD19 warhead at the natural N terminus of fragment 1 and the anti-CD3 at the C terminus of fragment 2, v1093. v1094 was designed to accommodate two different fusions at the natural termini of the albumin polypeptide (polypeptide sequences corresponding to SEQ ID NO:268). The scFv fusions were linked to the albumin molecule through a GGS linker at the N terminus and a GGSG (SEQ ID NO: 280) linker at the C terminus. The length of the linkers reflect the ones used in the MM-111 molecule, despite having a different sequence type.
Example 11: Heteromultimers with an Albumin Scaffold Bind Specifically to CD3- or CD19-Expressing Cells
[0421] The ability of Anti-CD3×CD19 loaded AlbuCORE-1 (v1092) to CD3+ and CD19+ cells was assessed using FACS and compared to WT-HSA loaded with the same anti-CD scFvs (v1094).
[0422] The results are shown in FIG. 4 and demonstrate that both v1092 and v1094 are able to bind to CD3-expressing Jurkat T-cells and to CD19-expressing Raji B-cells.
Example 12: Heteromultimers with Heterodimeric Fc or Albumin Scaffolds Show Comparable B-Cell Targeting and T-Cell Bridging
Example 13: Exemplary Heteromultimers have Higher Anti-CD3 K.SUB.D .and Higher Bmax in Binding to T and B Cell as Determined by FACS
Example 14: Heteromultimer v875 is Able to Bridge Jurkat CD3 T Cells and Raji CD19 B Cells
Example 15: Bridging of B and T Cells by Heteromultimers is Robust at Varying Antibody Concentrations or Cell Ratios
Example 16: Bridging of B and T Cells is Robust Across Differently Engineered Heteromultimers Constructs
Example 17: Effects of v875, v1380, v1379 on IL-2 Activated and Resting CD20+, CD4+, CD8+Subsets
Example 18: Exemplary Heteromultimers v875 and v873 Require the Presence of Both Effector T Cell and Target B Cells to Mediate Cytotoxic Effects
Example 19: Exemplary Heteromultimers can Mediate ADCC or Impaired ADCC to Target Daudi B Cells
[0444] Antibody-dependent cell-mediated cytotoxicity assays (ADCC) were performed with v875, v1379 and v1380 using Daudi cells as target B cells and FcRy3a immobilized NK92 cells as the effector cells (GS193761) by the following method.
Example 20: Exemplary Heteromultimers have Impaired CDC-Mediated Lysis of Daudi B Cells
[0449] Cell based complement dependent cytotoxicity assays (CDC) were performed with v875, v1379 and v1380 using Daudi cells as target B cells. Human serum from healthy donors (NHS) was used as the source of complement. 10 μl NHS (10% final concentration in 40 reaction volume) were added to each well to initiate the CDC cascade and incubated for 2 hours. Cell viability was measured with CellTiter-Glo@ Luminescent Cell Viability Assay Kit.
Example 21: Cell Proliferation and Cytokine Release Assessment of Exemplary Heteromultimers
Example 22: Exemplary Heteromultimers can Bridge Two or More Target B Cells Per Effector T Cell
[0465] The ability and ratio of numbers of T cell bridged to B cells was examined with the exemplary heteromultimer v875 by microscopy using the method described in Example 3 with the following modifications.
[0466] Labeled Raji B cells (red) and labeled Jurkat T cells (blue) were incubated for 30 min at RT with 3 nM of human IgG or v875. The cell suspension was concentrated by removing 180 μl of supernatant. Cell were resuspended in the remaining volume and imaged at 200× and 400×.
[0467] FIG. 30 shows the results from the T:B cell bridging microscopy comparing v875 and human IgG (3 nM) at 200× and 400× magnification; the phase image (top panel), fluorescence image (middle panel) and inverted fluorescence (bottom panel) are presented. FIG. 30A shows a direct comparison of human IgG and v875 at 200× magnification and illustrates a higher amount of bridging visible between Raji B cell and Jurkat T cells compared to human IgG. FIG. 30B and FIG. 30C show two fields of view for v875 (FIG. 30B) and human IgG (FIG. 30C) at 400× magnification. FIG. 30B shows images of v875-mediated immune complex formation between Jurkat T cells (dark grey cells in fluorescence inverted image) and Raji B cells (light grey cells in fluorescence inverted image), and that one Jurkat T cell can bridge 1-3 Raji B cells. FIG. 30C shows images following human IgG incubation with Jurkat T cells and Raji B cells. FIG. 30C shows an absence of the Jurkat-Raji bridging following incubation with human IgG, compared to the v875-mediated Jurkat: Raji bridging that is visible in FIG. 30B.
Example 23: Exemplary Heteromultimer Binding to Fcγ Receptors as Assessed by Surface Plasmon Resonance
Example 25: Expression and Purification of Heteromultimers
[0476] Description of the methods used in the expression and purification of exemplary heteromultimer are described in Example 2.
Example 26: Exemplary Heteromultimers can be Purified to >99% Heterodimer Purity and <1% Aggregates
Example 27: Exemplary Heteromultimers have a CH3 Tm that is Greater than 75° C.
[0487] CH3 domain stability of exemplary heteromultimers was examined by DSC using the following method. All DSC experiments were carried out using a GE VP-Capillary instrument. The proteins were buffer-exchanged into PBS (pH 7.4) and diluted to 0.3 to 0.7 mg/mL with 0.137 mL loaded into the sample cell and measured with a scan rate of 1° C./min from 20 to 100° C. Data was analyzed using the Origin software (GE Healthcare) with the PBS buffer background subtracted.
[0488] The DSC results shown in FIGS. 33A, B and C show that v875 has an estimated CH3 Tm >76° C. (FIG. 33A), v1380 has an estimated CH3 Tm >82.3° C. (FIG. 33B), and v1379 has an estimated CH3 Tm >82.5° C. (FIG. 33C).
Example 28: Design, Expression and Purification of CD3/CD20 and Additional CD3/CD19 Heteromultimer Constructs
[0489] V5850 (corresponding to polypeptide sequences SEQ ID NOs: 203, 205 and 207), v5851 (corresponding to polypeptide sequences SEQ ID NOs: 209, 211 and 213), v5852 (corresponding to polypeptide sequences SEQ ID NOs: 215, 217 and 219), v6324 (corresponding to polypeptide sequences SEQ ID NOs: 221 and 223), v6325 (corresponding to polypeptide sequences SEQ ID NOs: 225, 227 and 229), v1813 (corresponding to polypeptide sequences SEQ ID NOs: 231, 233 and 235), v1821 (corresponding to polypeptide sequences SEQ ID NOs: 237, 239 and 241), v1823 (corresponding to polypeptide sequences SEQ ID NOs: 243, 245 and 247) exemplify bispecific CD3/CD19 or CD3/CD20 hybrid heterodimeric Fc constructs. Bispecific hybrid variants are composed of a F(ab′) on either chain A or B paired with an scFv-Fc on the alternate polypeptide chain. Chain A of the heterodimer Fc is comprised of the following mutations: T350V_L351Y_F405A_Y407V and Chain B of the heterodimer Fc is comprised of the following mutations: T350V_T366L_K392L_T394W. v6324 exemplifies bispecific CD3/CD20 scFv heterodimeric Fc constructs. V1813, v1821, and v1823 exemplify CD3/CD20 common light chain heterodimeric Fc constructs. Common light chain variants are composed of two different F(ab′) s, each on complimentary heterodimer Fc, which share a single light chain. The specific variant composition is indicated in Table 7.
However, the specification does not teach dimer, e.g., homodimer comprises a first human IgG Fc and a second human IgG Fc wherein each Fc comprises a D265S, a L234A and L235A.
Regarding antibody (claims 8-11), enablement is not commensurate in scope with how to make and use the antibody (claim 8) and a pharmaceutical composition comprising said antibody (claim 14) without guidance as to the binding specificity of such antibody. Notably, the specification does not teach the structure, e.g., amino acid sequence of the heavy and light chain variable region of all antigen-binding domain, e.g., any scFv (claim 3), Fab (claim 4), antibody (claim 8), (humanized or human or monoclonal antibody (claim 9), multispecific antibody (claim 10) or bispecific antibody (claim 11) that bind to all different antigen (claim 20) and all CD3 complex (claim 21) as a pharmaceutical composition (claim 14) to enable one of skilled in the art to make and use without undue experimentation.
It is 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 (Protein Engineering, Design & Selection 22:159-168, 2009; PTO 1449) teach 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, see, e.g., Discussion.
Similarly, Edwards et al (J Mol Biol 334(1): 103-118, 2003; PTO 1449) find 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).
Poosarla et al (Biotechn. Bioeng., 114(6): 1331-1342, 2017; PTO 892) teach substantial diversity in designed mAbs (sharing less than 75% sequence similarity to all existing natural antibody sequences) that bind to the same 12-mer peptide, binding to different epitopes on the same peptide. Said reference further teaches “most B-cell epitopes... in nature consist of residues from different regions of the sequence and are discontinuous...de novo antibody designs against discontinuous epitopes present additional challenge.
Even assuming the antibody binds to CD3, Shepard et al (PLOSOne 18(6): e0273884, June 22, 2023; PTO 892) teach the unpredictability of swapping CD3 binding domains in the context of a BiTE in so far as the binding requirement to CD3 epsilon much less the extracellular epitope:
“We next sought to test our platform for flexibility with respect to screening novel T-cell engaging domains of the bispecific molecule. We developed a number of novel mouse monoclonal antibodies (mAbs) against human CD3 complex using a multi-antigen immunization strategy in mice and traditional hybridoma screening. Through this process, we were able to identify several monoclonal antibodies with reactivity to Jurkat cells (Fig 4A) and human T cells (Fig 4B). To assess whether scFvs derived from novel CD3-targeted mAbs would be functional within as part of a BiTE molecule, we cloned 4 anti-human CD3 single chain variable fragments into CD19 or EGFRvIII specific BiTE plasmids (Fig 4C). We then generated supernatants using transient transfection of HEK293T as described above. BiTE supernatants were screened for activity using Jurkat cells in co-culture with EGFRvIII-expressing U87-VIII targets or CD19-expressing Raji cells. Previously tested constructs using OKT3 CD3-engager arms showed activity with both EGFRvIII and CD19 specific BiTEs, whereas we detected activity for only one of our novel CD3-engager BiTEs and only when combined with an EGFRvIII-specific scFv (Fig 4D). To confirm these results, we repeated BiTE production and Jurkat co-culture screening of CD19 and EGFRvIII targeted BiTE molecules incorporating OKT3 or the novel 1E2 CD3-targeting single chain variable fragment. Whereas EGFRvIII BiTEs incorporating an scFv derived from the 1E2 mAb or OKT3 showed specific reactivity against EGFRvIII expressing U87-vIII cells, only CD19-OKT3 showed reactivity to CD19-expressing Raji cells (Fig 4E). These results indicate that the novel CD3-targeting 1E2-scFv is functional only for an EGFRvIII-targeting BiTE but not a CD19-targeting BiTE, likely due to the specific binding characteristics of the CD19 or EGFRvIII scFv elements.”
“Similarly, we also find that only one of the novel CD3-targeting scFvs tested here showed activity in BiTE format, and even then, activity was restricted to combination with EGFRvIII-targeting scFv and not with a CD19-specific scFv. Again, we have no insight into the failure rate for BiTE molecules in this assay, as the intent of this assay is to provide a rapid means for testing biological activity rather than focusing on various aspects of antibody characterization. We are currently undertaking molecular studies to test whether incorporating different linker domains may be able to improve the activity of BiTEs using the novel CD3-scFv reported to have activity here, something that may provide further insight into the design constraints for these BiTE molecules.”
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.
Regarding pharmaceutical composition (claims 13-14), the specification does not teach a representative number of species of dimer or antibody that correlated with binding to which antigen effective as a pharmaceutical composition for treating which disease. There are insufficient in vivo working example. It is unpredictable which dimer or antibody is effective as a pharmaceutical composition for treating which disease. 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).
In view of the lack of the predictability of the art to which the invention pertains as evidenced by Lloyd et al, Edwards, Poosarla and Shepard et al, the lack of guidance and direction provided by applicant, and the absence of in vivo working examples, it would require undue experimentation of one skilled in the art to practice the claimed invention, commensurate in scope with the claims. See page 1338, footnote 7 of Ex parte Aggarwal, 23 USPQ2d 1334 (PTO Bd. Pat App. & Inter. 1992).
In re wands, 858 F.2d at 737, 8 USPQ2d at 1404 (Fed. Cir. 1988), the decision of the court indicates that the more unpredictable the area is, the more specific enablement is necessary.
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 1-4, 7, 8, 9, 10, 13 and 14 are rejected under 35 U.S.C. 102 (a)(1) as being anticipated by WO2004/099249 publication (published November 2004; PTO 1449) as evidenced by Hezareh (J Virology 75(24): 12161-12168, 2001; PTO 1449).
Regarding claims 1-2, 8 and 10, the WO2004/099249 publication teaches Fc fusion (see para. [087], [109], [116]) or a dimeric IgG full-length antibody (see para. [079]) comprising a first polypeptide comprising an antigen binding domain VH-CH1 linked to an Fc comprising a CH2 and CH3 domain and a second polypeptide comprising an antigen binding domain, e.g., VH-CH1 linked to an Fc comprising CH2 and CH3 domain (see p. 1, para. [003], Figure 1, in particular) wherein the Fc (CH2-CH3 domain) is a human IgG1 Fc (see p. 16, para. [0037], [041]); the reference antibody comprises two Fc, together form a dimer in order to bind to human Fc receptors as evidenced in Figure 1, para. [005], [037].
The reference Fc polypeptide each comprises a CH2 variant having at least one substitutions such as L234A (p. 12, line 10, para. [025]), L235A (p. 12, line 11, p. 6, para. [025], [014]), and D265S (see p. 12, line 19), wherein the amino acid positions are numbered according to the EU index of Kabat, see entire document, p. 12, lines 3-4, p. 13, last line of para. [025]. The term “comprising” is open-ended. It expands the claimed Fc variant to include additional substitutions. Examples of antibody include alemtuzumab, see para. [039].
Evidentiary reference Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
Regarding claims 2-3, the WO2004/099249 publication teaches that the antibody comprises scFv, see para. [079].
Regarding claim 4, the WO2004/099249 publication teaches that the antibody comprises Fab, see p. 25, para. [079].
Regarding claim 7, the WO2004/099249 publication teaches that the IgG is an IgG1, see p. 27, para. [082], p. 32, para. [101], p. 29, [090], p. 31, [098].
Regarding claim 9, the WO2004/099249 publication teaches that the antibody is a humanized antibody (see p. 25, para. [080]), or a human antibody (see p. 25, para. [080]) or a monoclonal antibody (see p. 25, para. [079]).
Regarding claims 13-14, the WO2004/099249 publication teaches a pharmaceutical composition comprising antibody or Fc fusion and a pharmaceutically acceptable carrier, see p. 48, para. [123], reference claim 36.
Thus, the reference teachings anticipate the claimed invention.
Claims 1-4, 7-14, 19 and 20 are rejected under 35 U.S.C. 102 (a)(1) as being anticipated by US Pat No. 8,101,720 (issued Jan 24, 2012; PTO 1449) as evidenced by Hezareh (J Virology 75(24): 12161-12168, 2001; PTO 1449).
Regarding claim 1, the ‘720 patent teaches Fc fusions (see col. 3, line 34) or antibody, e.g., bispecific single chain Fv dimers (see col. 39, line 6) comprising two isolated Fc variant of human IgG1 Fc (see Summary of invention, col. 4, Fig 2a, col. 8, line 58-66, in particular) wherein each of the Fc comprising at least one substitutions such as L234A (col. 16, line 22), L235A (col. 16, line 24), and D265S (see col. 16, line 47), wherein the amino acid positions are numbered according to the EU index of Kabat, see col. 12, lines 40-44. The Fc variant comprises an antibody that is a human IgG1 antibody. The term “comprising” is open-ended. It expands the claimed Fc variant to include additional substitutions. Evidentiary reference Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
Regarding claims 2, 4, the ‘270 patent teaches that the reference Fc dimer comprises an antigen binding domain, e.g., Fab (see para. 7, line 10).
Regarding claims 2, 4, 8, the ‘720 patent teaches that the reference Fc variant comprises at least one antigen-binding domain such as full-length antibody as per claim 8 (see col. 22, lines 50-51) or Fc fusion protein (see col. 22, line 50). Examples of antibody include antibody fragment such as Fab as per claim 4 (see col. 23, lines 4-5), a humanized or fully human antibody (see col. 27, line 56) as per claim 9.
Regarding claim 3, the ‘720 patent teaches that the antibody comprises scFv joined to the Fc variant (see col. 23, line 11, col. 23, line 32).
Regarding claim 7, the ‘720 patent teaches that the IgG is an IgG1, see col. 20, line 55.
Regarding claim 9, the ‘720 patent teaches that the antibody is a humanized antibody (see col. 22, line 63).
Regarding claim 10, the ‘720 patent teaches multispecific antibodies, see col. 23, line 25.
Regarding claim 11, the ‘720 patent teaches bispecific antibodies, see col. 22, line 61, col. 23, line 25.
Regarding claim 12, the ‘720 patent teaches the dimer of Fc variants include homodimeric or heterodimeric molecules, see col. 22, lines 53-56, col. 38, lines 24-56.
Regarding claims 13 and 14, the ‘720 patent teaches pharmaceutical composition comprising antibody or Fc fusion and a pharmaceutically acceptable carrier, see col. 54, lines 55-67.
Regarding claims 19-20, ‘720 patent teaches the bispecific antibody binds to different antigen, see col. 23, line 24-27, in particular.
Thus, the reference teachings anticipate the claimed invention.
Claims 1-4, 6-9, 13 and 14 are rejected under 35 U.S.C. 102 (a)(1) as being anticipated by Escobar-cabrera (US20160102135, claimed priority to 61/829,973 filed May 31, 2013; PTO 892).
Regarding claim 1, Escobar-cabrera teaches isolated dimer, e.g., heterodimer comprising an human IgG1 Fc having two Fc polypeptides each comprising a variant CH2 (see para. [0081]) and a CH3 (see entire document, Summary of invention, para. [0052], [0071], [0088]) wherein each Fc comprises a L234A. a L235A (see para. [0025], [0026], [0028], [0029]), D265S (see para. [0030]).
Regarding claims 2-4, Escobar-cabrera teaches that the heterodimer further comprises at least one antigen-binding construct fused to the IgG Fc construct. In certain embodiments, the at least one antigen-binding construct is selected from a Fab fragment, an scFv, see para. [0074].
Regarding claim 6, Escobar-cabrera teaches that the first Fc chain A comprises T350V, L351Y, F405A, and Y407V, and the second Fc chain B comprises amino acid substitutions T350V, T366L, K392M and T394W, see para. [0234]. The term comprises is open ended. It expands the chain A to include S400E and chain B to include N390R.
Regarding claim 7, Escobar-cabrera teaches that the IgG is IgG1, see para. [0075].
Regarding claim 8, Escobar-cabrera teaches that the heterodimer is an antibody, see para. [0092], [0109].
Regarding claim 9, Escobar-cabrera teaches that the antibody is a monoclonal (see para. [0111]), a humanized monoclonal antibody (see para. [01231]).
Regarding claims 13 and 14, Escobar-cabrera teaches pharmaceutical composition comprising antibody or Fc fusion and a pharmaceutically acceptable carrier, see para. [0077]. Thus, the reference teachings anticipate the claimed invention.
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 of this title, 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 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 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 the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
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 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.
Claims 1 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over W02004/099249 publication (of record, published November 2004; PTO 1449) as evidenced in Hezareh et al (J Virology 75(24): 12161-12168, 2001; PTO 1449) in view of US Pat No. 9,574,010 (claimed earliest priority to 61/556,090, filed Nov 4, 2011; PTO 1449).
The teachings of the WO2004/099249 publication have been discussed supra. Evidentiary reference Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
The W02004/099249 publication does not teach the antibody dimer wherein one of the first Fc region further comprises amino acid substitutions F350V, L351Y, F405A, and Y407V, numbering according to EU index of Kabat and the other Fc region further comprises amino acid substitutions T350V, T366L, K392L, and T394W, numbering according to EU index of Kabat as per claim 6.
However, the ‘010 patent teaches various isolated heteromultimer construct comprising a modified first CH3 domain polypeptide comprising T350V,L351Y, F405A and Y407V and a modified second CH3 domain polypeptide comprising T350V, T366L, K392L and T394W that has increased stability with a melting temperature (Tm 81.8 °C) and improved purity, e.g., greater than 98% purity (see col. 39, Table 1.2, line 4), and decrease binding affinity for CD16a (FcγRIIIA) and CD32b (FcγRIIB) (see Table 1.3, last line). The ‘010 patent teaches the combination of substitutions promotes heterodimer formation with improved stability (see col. 27, line 35-37) and purity can be applied to other classes and isotypes of Fc regions, see col. 12, lines 8-11.
The ‘010 patent further teaches that the Fc variants may be combined with other Fc modifications, including but not limited to modifications that alter effector function. The invention encompasses combining an Fc variant of the invention with other Fc modifications to provide additive, synergistic, or novel properties in antibodies or Fc fusion proteins. Such modifications may be in the hinge, CH1, or CH2, (or CH3 provided it does not negatively alter the stability and purity properties of the present modified CH3 domains) domains or a combination thereof. It is contemplated that the Fc variants of the invention enhance the property of the modification with which they are combined. For example, if an Fc variant of the invention is combined with a mutant known to bind Fc.gamma.RIIIA with a higher affinity than a comparable molecule comprising a wild type Fc region; the combination with a mutant of the invention results in a greater fold enhancement in Fc.gamma.RIIIA affinity, see col. 56, lines 10-26. In one embodiment, the Fc variants of the present invention may be combined with other known Fc variants, see col. 56, line 27-46.
One skilled in the art will understand that the Fc variants of the invention may have altered Fc ligand (e.g., Fc.gamma.R, C1q) binding properties (examples of binding properties include but are not limited to, binding specificity, equilibrium dissociation constant (K.sub.D), dissociation and association rates (K.sub.off and K.sub.on respectively), binding affinity and/or avidity) and that certain alterations are more or less desirable. It is well known in the art that the equilibrium dissociation constant (K.sub.D) is defined as k.sub.off/k.sub.on. It is generally understood that a binding molecule (e.g., and antibody) with a low K.sub.D is preferable to a binding molecule (e.g., and antibody) with a high K.sub.D. However, in some instances the value of the k.sub.m or k.sub.off may be more relevant than the value of the K.sub.D. One skilled in the art can determine which kinetic parameter is most important for a given antibody application. For example a modified CH3 and/or CH2 that enhances Fc binding to one or more positive regulators (e.g., Fc.gamma.RIIIA) while leaving unchanged or even reducing Fc binding to the negative regulator Fc.gamma.RIIB would be more advantageous for enhancing ADCC activity. Alternatively, a modified CH3 and/or CH2 that reduced binding to one or more positive regulator and/or enhanced binding to Fc.gamma.RIIB would be advantageous for reducing ADCC activity. Accordingly, the ratio of binding affinities (e.g., equilibrium dissociation constants (K.sub.D)) can indicate if the ADCC activity of an Fc variant is enhanced or decreased. For example a decrease in the ratio of Fc.gamma.RIIIA/Fc.gamma.RIIB equilibrium dissociation constants (K.sub.D), will correlate with improved ADCC activity, while an increase in the ratio will correlate with a decrease in ADCC activity, see col. 56, lines 47-66.
Therefore, 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 the W02004/099249 publication, as evidenced by Hezareh and the ‘010 patent by including the combination of substitutions e.g., T350V, L351Y, F405A and Y407V in one of the Fc and a combination of substitution e.g., T350V, T366L, K392L and T394W in the other Fc as taught by the ‘010 patent to arrive at the claimed invention with a reasonable expectation of success, e.g., improved stability of the antibody dimer.
One of ordinary skill in the art would have been motivated to do so because the ‘010 patent teaches the particular substitutions promote heterodimer formation with improved stability (see col. 27, line 35-37) and purity can be applied to other classes and isotypes of Fc regions, see col. 12, lines 8-11.
One of ordinary skill in the art would have been motivated to do so because the ‘010 patent teaches the modification may be combined with other Fc modifications, including but not limited to modifications that alter effector function in the CH2 domain, see col. 56, lines 10-26.
One of ordinary skill in the art would have been motivated to do so because Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
The combination of substitutions e.g., L234A, L235A and DD265S (claim 1) is expected to reduce effector function and is an obvious variation of the reference teachings since each substitution has been taught in the art useful for reducing effector functions, e.g., decrease human IgG1 binding to FcγRI (CD64), FcγRII (CD32) and FcγRIII (CD16), decreases antibody dependent cytotoxicity (ADCC) known in the art.
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, 1395-97 (2007).
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.
Claims 1 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over US Pat No. 8,101,720 (issued Jan 24, 2012; PTO 1449) in view of US Pat No. 9,574,010 (claimed earliest priority to 61/556,090, filed Nov 4, 2011; PTO 1449) and Hezareh et al (J Virology 75(24): 12161-12168, 2001; PTO 1449).
The teachings of ‘720 patent have been discussed supra.
The ‘720 patent does not teach the combination of three substitutions L234A, L235A, and D265S as per claim 1 wherein the first Fc region further comprises amino acid substitutions F350V, L351Y, F405A, and Y407V, numbering according to EU index of Kabat and the second Fc region further comprises amino acid substitutions T350V, T366L, K392L, and T394W, numbering according to EU index of Kabat as per claim 6.
However, the ‘010 patent teaches various isolated heteromultimer constructs comprising a modified first CH3 domain polypeptide comprising T350V,L351Y, F405A and Y407V and a modified second CH3 domain polypeptide comprising T350V, T366L, K392L and T394W that has increased stability with a melting temperature (Tm 81.8 °C) and improved purity, e.g., greater than 98% purity (see col. 39, Table 1.2, line 4), while decreased binding affinity for CD16a (FcγRIIIA) and CD32b (FcγRIIB) (see Table 1.3, last line). The ‘010 patent teaches the combination of substitutions promotes heterodimer formation with improved stability (see col. 27, line 35-37) and purity can be applied to other classes and isotypes of Fc regions, see col. 12, lines 8-11.
The ‘010 patent further teaches: the Fc variants of the present invention may be combined with other Fc modifications, including but not limited to modifications that alter effector function. The invention encompasses combining an Fc variant of the invention with other Fc modifications to provide additive, synergistic, or novel properties in antibodies or Fc fusion proteins. Such modifications may be in the hinge, CH1, or CH2, (or CH3 provided it does not negatively alter the stability and purity properties of the present modified CH3 domains) domains or a combination thereof. It is contemplated that the Fc variants of the invention enhance the property of the modification with which they are combined. For example, if an Fc variant of the invention is combined with a mutant known to bind Fc.gamma.RIIIA with a higher affinity than a comparable molecule comprising a wild type Fc region; the combination with a mutant of the invention results in a greater fold enhancement in Fc.gamma.RIIIA affinity, see col. 56, lines 10-26. In one embodiment, the Fc variants of the present invention may be combined with other known Fc variants, see col. 56, line 27-46. One skilled in the art will understand that the Fc variants of the invention may have altered Fc ligand (e.g., Fc.gamma.R, C1q) binding properties (examples of binding properties include but are not limited to, binding specificity, equilibrium dissociation constant (K.sub.D), dissociation and association rates (K.sub.off and K.sub.on respectively), binding affinity and/or avidity) and that certain alterations are more or less desirable. It is well known in the art that the equilibrium dissociation constant (K.sub.D) is defined as k.sub.off/k.sub.on. It is generally understood that a binding molecule (e.g., and antibody) with a low K.sub.D is preferable to a binding molecule (e.g., and antibody) with a high K.sub.D. However, in some instances the value of the k.sub.m or k.sub.off may be more relevant than the value of the K.sub.D. One skilled in the art can determine which kinetic parameter is most important for a given antibody application. For example a modified CH3 and/or CH2 that enhances Fc binding to one or more positive regulators (e.g., Fc.gamma.RIIIA) while leaving unchanged or even reducing Fc binding to the negative regulator Fc.gamma.RIIB would be more advantageous for enhancing ADCC activity. Alternatively, a modified CH3 and/or CH2 that reduced binding to one or more positive regulator and/or enhanced binding to Fc.gamma.RIIB would be advantageous for reducing ADCC activity. Accordingly, the ratio of binding affinities (e.g., equilibrium dissociation constants (K.sub.D)) can indicate if the ADCC activity of an Fc variant is enhanced or decreased. For example a decrease in the ratio of Fc.gamma.RIIIA/Fc.gamma.RIIB equilibrium dissociation constants (K.sub.D), will correlate with improved ADCC activity, while an increase in the ratio will correlate with a decrease in ADCC activity, see col. 56, lines 47-66.
Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
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 the ‘720 patent with Hezareh and the ‘010 patent by including the substitutions e.g., T350V, L351Y, F405A and Y407V in one of the Fcs and the substitutions e.g., T350V, T366L, K392L and T394W in the other Fc as taught by the ‘010 patent to arrive at the claimed invention with a reasonable expectation of success, e.g., improved stability of the antibody dimer.
One of ordinary skill in the art would have been motivated to do so because the ‘010 patent teaches the particular substitutions promote heterodimer formation with improved stability (see col. 27, line 35-37) and purity can be applied to other classes and isotypes of Fc regions, see col. 12, lines 8-11.
One of ordinary skill in the art would have been motivated to do so because the ‘010 patent teaches the modification may be combined with other Fc modifications, including but not limited to modifications that alter effector function in the CH2 domain, see col. 56, lines 10-26.
One of ordinary skill in the art would have been motivated to do so because Hezareh teaches double substitutions L234A and L235A in the CH2 domain completely abolished FcγRI (CD64) binding (see p. 12163, Results, p. 12164, in particular), reduced antibody dependent cytotoxicity (ADCC) (see p. 12164, left col, FIG 2, in particular) and completely abashed binding to FcγRIIa (CD32a) and FcγRIIIa (CD16a), see p. 12166, left col.
The combination of substitutions e.g., L234A, L235A and DD265S (claim 1) is expected to reduce effector function and is an obvious variation of the reference teachings since each substitution has been taught in the art useful for reducing effector functions, e.g., decrease human IgG1 binding to FcγRI (CD64), FcγRII (CD32) and FcγRIII (CD16), decreases antibody dependent cytotoxicity (ADCC) known in the art.
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, 1395-97 (2007).
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.
Claims 1, 5, 12, 19-20 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over WO2004/099249 publication (published November 2004; PTO 1449) or US Pat No. 8,101,720 (issued Jan 24, 2012; PTO 1449) each in view of Von Kreudenstein et al (US20120149876 published June 14, 2012; PTO 892) and Bargou et al (Science 321: 974-977, August 15, 2008; PTO 14490).
The teachings of the WO2004/099249 publication and the ‘720 patent have been discussed supra.
The references above do not teach the dimer wherein one of the Fc polypeptide comprises scFv and the other Fc polypeptide comprises a Fab as per claim 5, wherein one of the antigen binding domain binds a CD3 complex as per claim 24.
However, Von Kreudenstein teaches multispecific or bispecific heterodimer (see paragraphs [0003], [0025]) comprising a first polypeptide comprising a first antigen-binding domain linked to a CH2-CH3 domain; paragraphs [0023]-[0025], and a second polypeptide comprising a second antigen binding domain-CH2-CH3 domain (see Figure 19 left)
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wherein the first polypeptide (left side) further comprises a scFv (Figure 19 and the second polypeptide further comprises a Fab (right side), see Figure 19 right, in particular.
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258
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The term “comprising” is open ended. It expands the first and second polypeptides to include additional binding sites as per claim 22. One of the binding sites (paragraph [0088]) binds a CD3 antigen (paragraph [0207]) and the other antigen binding site a CD19 antigen (paragraphs [0207], [0208]). The Fc region is from human IgG such as IgG1, see para. [0128]. The positions L351, F405, Y407, T366, K392 and T394 are numbering according to EU of Kabat, see Table B, in particular.
Regarding claim 20, Von Kreudenstein teaches Bispecific antibodies are antibody-based molecules that can simultaneously bind two separate and distinct antigens (or different epitopes of the same antigen), see para. [0004], [0006]. The bispecific antibodies are composed of a hybrid immunoglobulin heavy chain with a first binding specificity in one arm, and a hybrid immunoglobulin heavy chain-light chain pair (providing a second binding specificity) in the other arm. It was found that this asymmetric structure facilitates the separation of the desired bispecific compound from unwanted immunoglobulin chain combinations, see para. [0009]. Multispecific antibodies have binding specificities for at least two different antigens. While such molecules normally will only bind two antigens (i.e. bispecific antibodies, BsAbs), antibodies with additional specificities such as trispecific antibodies are encompassed by the instant invention. Examples of BsAbs include without limitation those with one arm directed against a tumor cell antigen and the other arm directed against a cytotoxic molecule, or both arms are directed again two different tumor cell antigens, or both arms are directed against two different soluble ligands, or one arm is directed against a soluble ligand and the other arm is directed against a cell surface receptor, or both arms are directed against two different cell surface receptors. Methods for making bispecific antibodies are known in the art, see para. [0201].
Regarding claim 21, Von Kreudenstein teaches virtually any molecule may be targeted by and/or incorporated into a variant Fc heterodimer protein (e.g., antibodies, Fc fusion proteins) including, but not limited to, CD3, CD19, see para. [0207]. The scFv used to generate bispecific protein, e.g., BITE™, which binds to CD3 complex, disclosed in US Patent 7,635,472, see para. [0008]. The CD3 complex denotes an antigen that is expressed on T-cell as part of the multimolecular T-cell receptor complex known in the art. The same BITE is used in instant application, see Example 1 of instant application.
The advantages of the heteromultimer variants are to promote heterodimer formation with increased stability and the variant has a melting temperature (Tm) greater than 70ºC, see para. [0129]. Von Kreudenstein teaches virtually any therapeutic antibody molecule (see para. [0028], [0209]) may incorporate into the Fc variant that forms heterodimeric protein (e.g., antibodies, Fc fusion proteins) including, but not limited to, the following list of proteins, CD3 and CD19, see para. [0207].
Von does not teach the construct binds to human CD19.
However, Bargou teaches bispecific antibody such as blinatumomab (also called MTS 03/MED 1-538) that hinds to human CD19 and human CD3 complex for treating human with non-Hodgkin’s B cell lymphoma (NHL) patients relapsed to standard therapy, see entire document, p. 974 -975.
Therefore, 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 WO2004/099249 publication and Von Kreudenstein or the ‘720 patent and Von Kreudenstein by linking any first and second Fc polypeptides having L234A, L235A and D265S of WO2004/099249 publication or the ‘720 patent to any antigen binding domain, e.g., Fab and/or scFv that bind to human CD3 and/or CD19 to the N and/or C-terminus of the Fc having the structure of Von Kreudenstein to arrive at the claimed invention with a reasonable expectation of success, e.g., bispecific or multispecific antibody that binds different antigen, e.g., human CD3 and human CD19 in order to treat human with Hodgkin’s B cell lymphoma (NHL) by targeting T cells expressing CD3 to cancer cells that expressed CD19.
The person of ordinary skill would have had a reasonable expectation of success in selecting Von Kreudenstein’s multispecific antibody that binds to human CD3 and human CD19 as the antigen binding domain in the WO2004/099249 publication and the ’720 patent’s human IgG Fc comprising L234A, L235A and D265S because such substitutions are expected to reduce FcγRs binding and/or effector functions, thereby side effects.
One of ordinary skill in the art would have been motivated to do so because Bargou teaches the bispecific antibody that binds to human CD3 and human CD 19 is useful for treating human with non- Hodgkin’s B cell lymphoma (NHL) patients relapsed to standard therapies, see entire document, p. 974 -975.
One of ordinary skill in the art would have been motivated to do so because Von Kreudenstein teaches the pair of Fc variants promotes heterodimer formation with increased stability and the variant has a melting temperature (Tm) greater than 70ºC, see para. [0129].
Thus, given the advantages of the CH3 variants taught by Von Kreudenstein, one would have been motivated to incorporate these modifications into the scFv-Fc bispecific constructs of Fab-Fc-scFv that binds to human CD3 and human CD19 of Bargou in order to increase their stability and purity.
Additionally, one would have been motivated with a reasonable expectation of success to use other therapeutic anti-CD3 antibody binding domains like that of muromonab/OKT3 taught by Von Kreudenstein as these antibodies are known to bind human CD3 for retargeting human T cell expressing CD3 to cancer cell that expressed human CD19 to treat cancer.
The claims would have been obvious because the substitution of a known element (i.e., VH and VL in the scFv-Fc bispecific antibody) for another (i.e. another VH and VL that is known to bind to human CD3 and human CD19) would have yielded predictable results (i.e. scFv-Fc bispecific antibody that binds to human CD3 and human CD19) to one of ordinary skill in the art before the effective filling date of the claimed invention.
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).
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.
Conclusion
SEQ ID NO: 133, 134, 137, 138, 141, 142, 38, 40, 42, 44, 46, 48 are free of prior art.
No claim is allowed.
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/PHUONG HUYNH/ Primary Examiner, Art Unit 1641
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