Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Claims 103-115, 117-120 and 122 are pending and 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 statement (IDS) submitted on August 6, 2025 has considered by the examiner and an initialed copy of the IDS is included with this Office Action.
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 103-115, 117-120 and 122 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 MPEP lists factors that can be used to determine if sufficient evidence of possession has been furnished in the disclosure of the Application. These include: (1) Actual reduction to practice, (2) Disclosure of drawings or structural chemical formulas, (3) Sufficient relevant identifying characteristics (such as: i. Complete structure, ii. Partial structure, iii. Physical and/or chemical properties, iv. Functional characteristics when coupled with a known or disclosed, and correlation between function and structure), (4) Method of making the claimed invention, (5) Level of skill and knowledge in the art, and (6) Predictability in the art. “Disclosure of any combination of such identifying characteristics that distinguish the claimed invention from other materials and would lead one of skill in the art to the conclusion that the applicant was in possession of the claimed species is sufficient.” MPEP § 2163.
Claim 103 encompasses a method for of increasing complement activation in a human subject, the method comprising administering to the subject a therapeutically effective amount of any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer,
wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain.
Claim 104 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acids at the positions corresponding to E345, E430, and S440 are R, G, and Y, respectively.
Claim 105 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acid at the position corresponding to E345, E430, and S440 in a human IgG1 heavy chain are R, G, and Y, respectively.
Claim 106 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are K, G, and Y, respectively.
Claim 107 encompasses the method of claim 103, wherein in one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are R, S, and Y, respectively.
Claim 108 encompasses the method of claim 103, wherein in one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are R, G, and W, respectively.
Claim 109 encompasses the method of claim 103, wherein the dimeric protein is an antibody.
Claim 110 encompasses the method of claim 109, wherein the antibody is any monoclonal antibody.
Claim 111 encompasses the method of claim 103, wherein each Fc polypeptide comprises at least the CH2 and CH3 regions of a human IgGl.
Claim 112 encompasses the method of claim 103, wherein one or both polypeptides of the dimer further comprises a region capable of covalent binding between said first and second polypeptides.
Claim 113 encompasses the method of claim 103, wherein one or both polypeptides of the dimer further comprises a hinge region of an immunoglobulin heavy chain.
Claim 114 encompasses the method of claim 103, wherein the first and second polypeptides of the dimer are interconnected via hinge region disulfide bonds.
Claim 115 encompasses the method of claim 103, wherein one or both polypeptides of the dimer comprise a full-length heavy chain constant region.
Claim 117 encompasses the method of claim 103, wherein the dimeric protein is a homodimer.
Claim 118 encompasses the method of claim 103, wherein the dimeric protein is any heterodimer.
Claim 119 encompasses the method of claim 103, wherein the dimeric protein is predominantly in oligomeric form in a phosphate buffer at a pH of about 6.8.
Claim 120 encompasses the method of claim 103, wherein the dimeric protein is predominantly in monomeric form at a pH of less than 6.0.
Claim 122 encompasses the method of claim 103, wherein the human subject has cancer.
Regarding any dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer, the specification discloses:
[0028] FIGS. 3A and 3B: Sequence alignment of anti-EGFR antibody 2F8 in an IgG1 (SEQ ID NO:3), IgG4 (SEQ ID NO:5) and (partial) IgG3 (SEQ ID NO:6) backbone. Amino acid numbering according to Kabat and according to the Eu-index are depicted (both described in Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991)).
Example 10
[0621] E345R Rescues CDC by EGFR Antibody 2F8, which can be Further Enhanced by Monovalent Target Binding
[0622] As described in Examples 3 and 12, E345R enhanced or rescued CDC for antibodies recognizing different hematological tumor targets (CD20 and CD38). To extend the analysis to a solid tumor antigen, the effect of E345R on the CDC capacity of the EGFR antibody 2F8 was tested on A431 epidermoid carcinoma cells. Furthermore, the effect of monovalent EGFR targeting on E345R-mediated CDC induction was tested using a bispecific EGFRxCD20 antibody (IgG1-2F8-E345R/F405L x IgG1-7D8-E345R/K409R) on EGFR-positive, CD20-negative A431 cells.
[0623] Bispecific antibodies were generated as described in Example 8. For the CDC assay, 5×10.sup.6 A431 cells/mL were labeled with 100 μCi .sup.51Cr for 1h at 37° C. Cells were washed three times with PBS and resuspended in medium at a concentration of 1×10.sup.5 cells/ml. 25,000 labeled cells were incubated in round-bottom 96-well plates with a concentration series of unpurified antibodies (0-30 μg/ml in 3-fold dilutions) in a total volume of 100 μl for 15 min at RT. Next, 50 μl normal human serum dilution was added as a source of complement (25% final concentration) and incubated in a 37° C. incubator for 1h. Cells were spun down (3 min at 300×g) and 25 μl supernatant was added to 100 μl microscint in a white 96 well optiplate (PerkinElmer) for incubation on a shaker (750 rpm) for 15 min. .sup.51Cr release was determined as counts per minute (cpm) on a scintillation counter. Maximum lysis (100%) was determined by the .sup.51Cr level measured in the supernatant of Triton X-100-treated cells. Spontaneous lysis was determined by the .sup.51Cr level measured in the supernatant of cells incubated without antibody. Specific cell lysis was calculated according to the formula: Specific lysis=100×(cpm sample−cpm spont)/(cpm max−cpm spont).
[0624] FIG. 11 shows that IgG1-2F8-E345R/F405L is able to lyse A431 cells by CDC, whereas wild type 2F8 is not capable of killing A431 cells. These data show that CDC activity can be rescued in the EGFR antibody 2F8 by introduction of the E345R mutation. This potentially extends the applicability of the CDC enhancing E345R mutation to antibodies targeting solid tumor antigens.
[0625] Bispecific EGFRxCD20 antibody IgG-2F8-E345R/F405L x IgG1-7D8-E345R/K409R, showed further enhancement of CDC on the EGFR-positive, CD20-negative A431 cells.
[0626] These data further support the hypothesis that monovalency facilitates the formation of Fc-Fc interactions and subsequent CDC induction as postulated for a CD38 binding antibody described in Example 8.
Example 11
E345R Enhances or Rescues CDC by CD38 Antibody 003 and CD20 Antibodies 11B8 and Rituximab
[0627] As described in Examples 3 and 12, E345R enhances or induces CDC activity of several antibodies with different target specificities (CD20, CD38 and EGFR), as was tested on multiple cell lines expressing variable levels of said antigens. Therefore, introduction of the E345R mutation was considered to be a general mechanism to enhance or rescues CDC for existing antibodies. To further support this, the effect of the E345R mutation on CDC was tested for more antibodies with variable intrinsic CDC efficacy on Daudi and Wien133 cells: CD38 antibody 003, described in WO 2006/099875 and CD20 antibodies rituximab (type I) and 11B8 (type II), described in WO 2005/103081. CD20 antibodies can be divided in two subgroups (Beers et al. Seminars in Hematology 47, (2) 2010, 107-114). Type I CD20 antibodies display a remarkable ability to activate complement and elicit CDC by redistributing the CD20 molecules in the plasma membrane into lipid rafts, which cluster the antibody Fc regions and enabling improved C1q binding. Type II CD20 antibodies do not appreciably change CD20 distribution and without concomitant clustering, they are relatively ineffective in CDC. 0.1×10.sup.6 Daudi or Raji cells were pre-incubated in round-bottom 96-well plates with a concentration series of unpurified antibodies (0.001, 0.003, 0.01, 0.03, 0.1, 0.3, 1.0, 3.0, 10.0 μg/mL) in a total volume of 70 μl for 15 min on a shaker at RT. Next, 30 μl normal human serum was added as a source of C1q (30% final concentration) and incubated in a 37° C. incubator for 45 min. The reaction was stopped by putting the plates on ice. 10 μl propidium iodide was added and cell lysis was determined by FACS.
[0628] FIG. 12 shows that the E345R mutation enhanced CDC for all tested antibodies on both (A) Daudi and (B) Wien133 cells. Interestingly, at the used concentrations all antibodies that did not induce CDC in the wild type format, induced CDC efficiently after introduction of the E345R mutation: CD38 mAb 003 and CD20 type II mAb 11B8 on Daudi cells, and CD38 mAbs 005 and 003 and CD20 type II mAb 11B8 on Wien133 cells. These data suggest that enhancement of antibody oligomerization, more specifically by introduction of an E345R mutation, is a general mechanism to enhance or rescue CDC by existing antibodies.
Example 13
[0636] Enhanced CDC by E345R Mutation in Rituximab in Different B Cell Lines with Similar CD20 Expression but Different Levels of Membrane-Bound Complement Regulatory Proteins
[0637] Examples 11 and 14 show that the CDC efficacy of wild type rituximab on Daudi and Wien133 cells was enhanced by introducing the E345R mutation. This enhanced CDC efficacy results from the E345R-mediated stabilization of Fc-Fc interactions. The concomitantly formed hexameric antibody ring structure on the target cell membrane can then promote efficient generation of the membrane attack complex by facilitating the capture and concentration of activated complement components close to the cell membrane. As a result of this efficient complement activation, the inhibiting effects of membrane-bound complement regulatory proteins (mCRP) could be partly overcome. Overexpression of mCRPs, such as CD55, CD46 and CD59, is considered as a barrier for successful immunotherapy with monoclonal anti-tumor antibodies (Jurianz et al., Mol Immunol 1999 36:929-39; Fishelson et al. Mol Immunol 2003 40:109-23, Gorter et al., Immunol Today 1999 20:576-82, Zell et al., Clin Exp Immunol. 2007 December 150(3):576-84). Therefore, the efficacy of rituximab-E345R was compared to that of wild type rituximab on a series of B cell lines with different levels of the mCRPs CD46, CD55 and CD59, but comparable levels of the CD20 target expression.
[0640] FIG. 14A-D shows that introduction of E345R in wild type rituximab resulted in enhanced CDC efficacy as observed by an increased maximal lysis and decreased EC.sub.50 for all tested B cell lines.
[0643] FIG. 15A shows that wild type CD20 antibody IgG1-7D8 showed a maximal CDC-mediated killing of 80% of the Raji cells, which was already reached after 5 min under the tested conditions. However, for IgG-7D8-E345R, 80% killing of Raji cells was observed even faster, after 3 min. Maximal lysis by IgG-7D8-E345R (95%) was also reached after 5 minutes.
[0644] FIG. 15B shows that also for wild type CD20 antibody rituximab, which is less potent than 7D8 to induce CDC on the used Raji cells, introduction of the E345R mutation resulted in faster killing of the target cells. Wild type rituximab showed a maximal CDC-mediated killing of 32%, which was reached after 20 minutes. Rituximab-E345R reached 32% killing already after approximately 3 minutes and remarkably, maximal lysis by rituximab-E345R (85%) was also reached after 20 minutes.
Example 18
E345R Induced CDC in IgG2, IgG3 and IgG4 Antibody Isotypes
[0663] To test if the introduction of oligomerization-promoting mutations can stimulate the CDC activity of non-IgG1 antibody isotypes, isotypic variants of the CD38 antibody IgG-005 were generated with constant domains of human IgG2, IgG3 or IgG4 yielding IgG2-005, IgG3-005 and IgG4-005 by methods known in the art. Furthermore, the oligomerization enhancing E345R mutation was introduced in all these antibodies, yielding IgG2-005-E345R, IgG3-005-E345R and IgG4-005-E345R. In a similar way, also IgG2-003 and IgG2-003-E345R were generated from CD38 antibody IgG1-003. CDC efficacy of the different isotypes was compared in an in vitro CDC assay.
[0664] 0.1×10.sup.6 Wien133 cells were pre-incubated in round-bottom 96-well plates with 10 μg/ml unpurified antibodies in a total volume of 100 μl for 15 min on a shaker at RT. IgG1-005-E345R was added at 3.0 μg/ml. Next, 25 μl normal human serum was added as a source of complement (20% final concentration) and incubated in a 37° C. incubator for 45 min. The reaction was stopped by putting the plates on ice. 10 μl propidium iodide was added and cell lysis was determined by FACS.
[0665] FIG. 19 shows that IgG2-005, IgG2-003, IgG3-005 and IgG4-005 were unable to lyse either (A) Daudi or (B) Wien133 cells efficiently under the tested conditions (the observed 20% lysis was considered as background). Introduction of the E345R mutation enabled potent CDC on Daudi cells by all IgG isotypes tested. These results were confirmed using CDC on Wien133 cells, albeit that IgG3-005-E345R displayed limited CDC activity relative to the other isotypic variants. These data indicate that besides IgG1, an oligomerization enhancing mutation such as E345R can also be applied to promote CDC activity of IgG2, IgG3 and IgG4 antibodies.
Example 20
IgG1-005-E345R/E430G/S440Y Forms Non-Covalent, Hexameric Complexes in Solution
[0671] The IgG1-005-E345R/E430G/S440Y triple mutant was prepared using the Quikchange site-directed mutagenesis kit (Stratagene, US). Briefly, forward and reverse primers encoding the desired mutation E345R were used to replicate full length plasmid DNA template encoding the IgG1-005 heavy chain with IgG1m(f) allotype. The resulting DNA mixture was digested using DpnI to remove source plasmid DNA and used to transform E. coli. Mutant plasmid DNA isolated from resulting colonies was checked by DNA sequencing (Agowa, Germany). The E430G mutation was introduced into the IgG1-005-E345R backbone using the same strategy. The S440Y mutation was introduced into the IgG1-005-E345R/E430G backbone using the same strategy. Plasmid DNA mixtures encoding both heavy and light chain of antibodies were transiently transfected to Freestyle HEK293F cells (Invitrogen, US) using 293fectin (Invitrogen, US) essentially as described by the manufacturer. The resulting antibody is a homodimer containing the E345R/E430G/S440Y triple mutation in both heavy chains.
[0672] IgG1-005 and IgG1-005-E345R/E430G/S440Y antibodies were purified by protein A affinity chromatography. The cell culture supernatants were filtered over a 0.20 μM dead-end filter, followed by loading on a 5 mL Protein A column (rProtein A FF, GE Healthcare, Uppsala, Sweden) and elution of the IgG with 0.1 M citric acid-NaOH, pH 3. The eluate was immediately neutralized with 2 M Tris-HCl, pH 9 and dialyzed overnight to 12.6 mM sodium phosphate, 140 mM NaCl, pH 7.4 (B. Braun, Oss, The Netherlands). After dialysis, samples were sterile filtered over a 0.20 μM dead-end filter. Purified proteins were analyzed by SDS-PAGE, native PAGE, HP-SEC, multiple angle light scattering (MALS), and dynamic light scattering (DLS).
[0673] SDS-PAGE was performed under reducing and non-reducing conditions on 4-12% NuPAGE Bis-Tris gels (Invitrogen, Breda, The Netherlands) using a modified Laemmli method (Laemmli 1970 Nature 227(5259): 680-5), where the samples were run at neutral pH. The SDS-PAGE gels were stained with Coomassie and digitally imaged using the GeneGenius (Synoptics, Cambridge, UK). FIG. 21 shows that IgG1-005-E345R/E430G/S440Y displayed behavior typical of IgG1 antibodies with disulfide bridged heavy and light chains. A single molecular species with apparent MW of approximately 150 kDa was visible under non-reducing conditions, while under reducing conditions a heavy chain with apparent MW of 50 kDa and light chain of 26 kDa were visible. We concluded that, under denaturing conditions, a monomeric molecule is formed displaying behavior highly similar to wild type IgG1 antibodies.
[0674] Native PAGE was performed under non-reducing conditions using a Sebia Hydragel 15/30 protein gel (Westburg, Leusden, The Netherlands), acid violet-staining and run on a Hydrasys instrument (Sebia, Vilvoorde, Belgium). FIG. 21 shows that IgG-005-E345R/E430G/S440Y ran at a height similar to that of the unrelated IgG1-b12 control antibody, albeit slightly more diffuse. The observed diffuse staining could be caused by formation of unstable complexes, but under these PAGE conditions, the IgG1-005-E345R/E430G/S440Y behaved predominantly like a monomeric IgG1 molecule.
Example 25
The Formation of Non-Covalent Hexameric IgG Complexes by Introducing the E345R/E430G/S440Y Triple Mutation Occurs Irrespective of the Fab Domain.
[0704] The formation in solution of non-covalently bound, hexameric antibody complexes by introducing the E345R/E430G/S440Y (RGY) triple mutation was demonstrated for CD38 antibody 005 in Example 20. In this experiment formation of non-covalent hexameric IgG complexes of other human IgG1 antibodies that differ in their Fab domains: CD20 antibodies 7D8 and rituximab, EGFR antibody 2F8 and C. albicans mannan antibody M1g1. The generation and purification of the triple mutant antibodies and HP-SEC analyses were performed essentially as described in Example 20.
[0705] FIG. 34 shows that all triple mutant antibodies showed a large fraction oligomer: IgG1-7D8-RGY (67.2%) (FIG. 34A), IgG1-ritux-RGY (83.6%) (FIG. 34B), IgG1-2F8-RGY (74.5%) (FIG. 34C), and IgG1-M1-RGY (74.5%) (FIG. 34D). These data indicate that the concept of E345R/E430G/S440Y for inducing self-assembly of antibodies into hexamers in solution can be generally applied to IgG1 sequences, irrespective of Fab domain primary structure.
Example 26
CDC by CD20 Antibodies Containing the E345R/E430G/S440Y Triple Mutation in an Ex Vivo CDC Assay on Patient-Derived CD20-Positive CLL Cells.
[0706] Frozen CLL PB CD19+/CD5+ B cells (Relapsed/Refractory) isolated from CLL peripheral blood mononuclear cells were purchased from Allcells, Emeryville, Calif. CDC was performed as described in Example 21, with the exception that 20,000 cells per 96-well plate were used. CD20 expression was determined as 39,000 Specific Antibody-Binding Capacity (sABC) by QIFIKIT, Dako, Glostrup, Denmark. FIG. 35 shows that CD20 antibodies containing the E345R/E430G/S440Y triple mutation showed functional CDC activity on CD20-positive primary CLL cells. Introduction of the E345R/E430G/S440Y mutation resulted in more efficient CDC-mediated killing (lower EC50) of primary CLL cells by 7D8 (FIG. 35A) and enabled potent CDC by rituximab, which did not show any killing activity in the WT format (FIG. 35B).
Example 31
[0728] Reversible Oligomerization of Antibody Molecules with Fc-Fc Interaction Enhancing Mutations can be Controlled by pH.
[0729] Example 23 showed that antibody IgG1-005-E345R/E430G/S440Y, here abbreviated to IgG1-005-RGY, was capable of hexamerization at pH 6.8, while lowering the pH to 5.0 dissolved the hexameric complex in individual monomeric subunits. To characterize this property in detail, 50 mM citric acid and 100 mM Na.sub.2HPO.sub.4 were mixed in different ratios to generate mobile phase buffers at pH 5.0, 5.5, 6.0, 6.5 and 7.0. IgG1-005-RGY samples were exchanged into these buffers and separated by HP-SEC using the matching mobile phase. FIG. 45A shows that lowering the pH resulted in disassembly of multimeric complexes into monomeric subunits; that a pH of approximately 5.0 was needed to eliminate multimers from the mixture; and that at pH 6.0, approximately half of the complexes had disassembled.
Example 35
[0743] Introduction of the Triple Mutations E345R/E430G/S440Y into Anti-EGFR Antibody IgG1-2F8 Enhances Efficacy of CDC-Mediated Lysis of EGFR-Positive Solid Tumor Cell Lines.
[0744] To test if introduction of the triple mutations E345R/E430G/S440Y into a solid tumor target antibody could lead to activation of complement-mediated lysis, IgG1-2F8-E345R/E430G/S440Y (here referred to as IgG1-2F8-RGY) was generated by methods known in the art.
[0745] CDC efficacy by IgG1-2F8-RGY was tested on EGFR-positive A431 and Difi tumor cell lines and was compared to wild type IgG1-2F8 and the control antibodies IgG-005 and IgG1-005-RGY. The control antibodies recognize CD38, which is expressed on neither A431 nor Difi cells.
[0746] After the solid tumor cells were detached by using trypsin-EDTA in phosphate-buffered saline (PBS), the cells were washed and passed through a 40 μm nylon cell strainer (DB Falcon™) and resuspended in PBS at a concentration of 1.0×10.sup.6 cells/ml. Cells were stained for 30 minutes at 37° C. using SYBR Green (SYBR Green 57563 in DMSO, Invitrogen, 25000× diluted). After centrifugation (1200 rpm, 5 minutes at RT), cells were resuspended in RPMI1640/0.1% BSA at a concentration of 3.0×10.sup.5 cells/ml. Antibody serial dilutions (0.0003-10 μg/ml) were prepared in RPMI/0.1% BSA supplemented with TOPRO-3 (TOPRO-3 iodide T3605, diluted 1600×). Cells were seeded at 30,000 cells per well into flat bottom 96 wells plates (black 96-Well ABI™ 4315480 FMAT Plates); after addition of the antibody serial dilutions, plates were incubated for 15′ on a shaker (300 rpm, RT). Normal Human Serum (NHS, Sanquin) was added at 20% final concentration. Plates were incubated for 45 minutes at 37° C. The amounts of dead cells (TOPRO-3 positive) and total cells (SYBR Green positive) were determined using a Celigo® imaging cytometer (Brooks Life Science Systems). Results were analyzed using GraphPad Prism 5.04.
[0747] FIG. 49 shows that the efficacy to induce complement-mediated lysis of EGFR-positive solid tumor cells was considerably higher for IgG1-2F8-RGY than wild type IgG1-2F8.
Example 36
IgG1-005-RGY Shows Target-Independent Complement Activation in Contrast to Wild Type IgG1-005.
[0748] In example 20, the cloning of antibody IgG1-005-E345R/E430G/S440Y, here abbreviated to IgG1-005-RGY, was described. To test if IgG1-005-RGY could activate complement in solution in the absence of target cells, the formation of C4d, a marker for classical complement pathway activation, was analyzed. Complement activation was determined by measuring C4d concentrations after incubating 100 μg/ml antibody in 90% normal human serum for 1 hour at 37° C. in low protein binding 96 wells polypropylene microplates (U-shaped and sterile; Greiner 650261). C4d concentrations were measured in an ELISA (MicroVue C4d EIA kit, Quidel Corporation) according to the manufacturer's instructions. A heat aggregated IgG (HAG) sample was used as positive control for complement activation in solution. FIG. 50 shows that HAG induced efficient C4d production, while wild type IgG-005 did not show complement activation under these conditions. In contrast, IgG1-005-RGY induced elevated C4d levels, indicative of complement activation in solution.
The disclosure of just three IgG1 antibodies rituximab that binds to CD20, CD38 specific antibody 003 or EGFR specific antibody 2F8 is not representative of the genus of dimeric protein (claim 103), or antibody (claim 109 or monoclonal antibody (110) that binds to any tumor antigen present on the subject of a tumor cell associated with the cancer. The dimeric protein may not be an antibody.
The specification does not describe the structure-identifying information e.g., amino acid sequences of such as the heavy and light chain variable domains or the six CDRs about the dimeric proteins or antibodies that bind to dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer wherein the dimeric comprises a first and second Fc polypeptides from human IgG1, IgG2, IgG3 or IgG4 wherein one or both Fc has triple substitutions E345R, E430G and S440Y or E345K, E430G and S440Y or E345R, E430S and S440Y or E345R, E430G and S440W.
The specification does not describe a representative number of species falling within the scope of the genus or structure 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 dimeric protein or antibody themselves for a method for of increasing complement activation in a human subject.
Regarding human subject (claim 103), the subject encompasses healthy subject and subject who has cancer (claim 122). There are no in vivo working example of administering any dimeric protein above to a healthy human subject. The claimed invention as a whole may not be adequately described where an invention is described solely in terms of its binding function and there is no described or art-recognized correlation or relationship between the structure of the invention and its function (see MPEP 2163).
When a patent claims a genus using functional language, e.g., tumor antigen present on the surface of a tumor cell associated with the cancer to define a desired result, “the specification must demonstrate that the applicant has made a generic invention that achieves the claimed result and do so by showing that the applicant has invented species sufficient to support a claim to the functionally-defined genus.” AbbVie Deutschland GmbH & Co., KG v. Janssen Biotech, Inc., 759 F.3d 1285, 1299 (Fed. Cir. 2014) (quoting Ariad, 598 F.3d at 1349).
The Federal Circuit has held that
“A sufficient description of a genus . . . requires the disclosure of either a representative number of species falling within the scope of the genus or structural features common to the members of the genus so that one of skill in the art can "visualize or recognize" the members of the genus.”
Ariad at 1350 (quoting Eli Lilly, 119 F.3d at 1568-69). But “merely drawing a fence around the outer limits of a purported genus is not an adequate substitute for describing a variety of materials constituting the genus and showing one has invented a genus.” Id.
The state of the art at the time the invention was made recognized 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. of record, Protein Engineering, Design & Selection 2009, 22:159-168; see, e.g., Discussion, PTO 892).
Similarly, Edwards et al., (of record, J Mol Biol. 2003 Nov 14;334(1): 103-118, 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 or epitope of such antigen (as held in AbbVie Deutschland GMBH v. Janssen Biotech, 111 USPQ2d 1780, 1790 (Fed. Cir. 2014).
As in Amgen, the pending claims of the instant case attempt to describe a genus of antibodies by describing something that is not an antibody, i.e. the antigen to which the antibody binds. Also analogous to Amgen, the fact that antigenic structures are known in detail would enable one of skill in the art to make antibodies meeting the binding limitations of the claims. As noted in Amgen, however, this is not enough to meet the written description requirement.
In AbbVie Deutschland GMBH v. Janssen Biotech, 111 USPQ2d 1780, 1790 (Fed. Cir. 2014), a claim drawn to a genus of antibodies having a recited binding affinity and binding specificity to a fully characterized antigen was found to be invalid for lack of written description such that it was not infringed by a subsequently disclosed antibody having all of the recited functional characteristics but a completely different structure (amino acid sequence). The Court held:
“It is true that functionally defined claims can meet the written description requirement if a reasonable structure-function correlation is established, whether by the inventor as described in the specification or known in the art at the time of the filing date... The asserted claims attempt to claim every fully human IL-12 antibody that would achieve a desired result, i.e., high binding affinity and neutralizing activity, and cover an antibody as different as Stelara®, whereas the patents do not describe representative examples to support the full scope of the claims. (AbbVie, 759 F.3d at 1298; 111 USPQ2d at 1791) (emphasis added).
Thus, the Amgen and the AbbVie decisions each support the finding that the detailed knowledge of one antibody structure does not reliably predict the structure of other antibodies that bind to the same antigen or epitope of an antigen and have the same effects. No structure-function relationship is established.
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.
Applicant is reminded of the recent decision by the Federal Circuit in which it is stated: “Claiming antibodies with specific properties, e.g., an antibody that binds to human TNF-α with A2 specificity, can result in a claim that does not meet written description even if the human TNF-α protein is disclosed because antibodies with those properties have not been adequately described.” Centocor Ortho Biotech Inc. v. Abbott Laboratories, 97 USPQ2d 1870 (Fed. Cir. 2011).
While one could test a plurality of antibodies to determine which, if any, have the requisite functional characteristics of the claimed antibody, a “mere wish or plan” for obtaining the claimed invention is not adequate written description. See Regents of the Univ. of Cal. v. Eli Lilly & Co., 119 F.3d 1559, 1566 (Fed. Cir. 1997); and Centocor Ortho Biotech Inc. v. Abbott Laboratories, 97 USPQ2d 1870 (Fed. Cir. 2011). So again, in this case, it seems the actual inventive work of producing at least a substantial number of the claimed antibodies would be left for subsequent inventors to complete.
Then, from the recent Court decision, AbbVie Deutschland GmbH & Co. v. Janssen Biotech, Inc. (Fed. Cir. 2014) with regard to the written description requirement, “analogizing the genus to a plot of land, if the disclosed species only abide in a corner of the genus, one has not described the genus sufficiently to show that the inventor invented, or had possession of, the genus. He only described a portion of it.” Indeed that is the case here too. The decision continues, explaining:
With the written description of a genus, however, merely drawing a fence around a perceived genus is not a description of the genus. One needs to show that one has truly invented the genus, i.e., that one has conceived and described sufficient representative species encompassing the breadth of the genus. Otherwise, one has only a research plan, leaving it to others to explore the unknown contours of the claimed genus. See Ariad, 598 F.3d at 1353 (The written description requirement guards against claims that “merely recite a description of the problem to be solved while claiming all solutions to it and . . . cover any compound later actually invented and determined to fall within the claim’s functional boundaries.”). Id. p. 23.
In this case, since the claims are so broad, and the disclosure is so comparably limited, it is submitted that any alleged conception has no more specificity than simply a wish to know the identity of any material with that requisite biological properties, which can be used to practice the claimed method so as to achieve the claimed objective or effect.
Therefore, only a method of increasing Complement Activation, the method comprising administering to a human subject in need thereof a therapeutically effective amount of a dimeric antibody protein, wherein the dimeric antibody protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
(a) the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain, 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).
Applicants’ arguments filed August 6, 2025 have been fully considered but are not found persuasive.
Applicant’s position is that solely to expedite prosecution, claim 103 has been amended to be drawn to a method of increasing complement activation in a human subject, wherein the method comprises administering to the subject a dimeric protein having the recited amino acid residues at positions 345, 430, and 440, wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440. Such methods are supported throughout the specification, for example, in Example 26, which demonstrates in an ex vivo CDC assay that a representative antibody comprising amino acid mutations E345R/E430G/S440Y induced CDC activity more efficiently than an antibody lacking the substitutions (i.e., rituximab). The increased CDC of the antibodies having the triple mutations was also evident on various tumor cell lines (see Examples 35 and 36).
With respect to the Office's assertion that "oligomeric form" implies the antibody precipitates or clumps together at pH about 6.8, Applicant respectfully disagrees. Indeed, the Office has not provided any evidence to support this assertion. In fact, as demonstrated in the Examples, the antibodies comprising the claimed mutations are able to oligomerize and form hexamers in solution, and exert CDC increasing effects. Nowhere in the working examples is there evidence that the antibodies precipitate or clump together.
For at least the foregoing reasons, the full scope of the amended claims are supported by the specification. Accordingly, Applicant respectfully requests that the rejection be withdrawn.
In response, the amendment to claim 103 is acknowledged.
Amended claim 103 encompasses a method for of increasing complement activation in a human subject, the method comprising administering to the subject a therapeutically effective amount of any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer,
wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain.
Regarding any dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer, the specification discloses just three IgG1 antibodies, namely rituximab that binds to CD20, CD38 specific antibody 003 or EGFR specific antibody 2F8. Three species are not representative of the genus of dimeric protein (claim 103), or antibody (claim 109 or monoclonal antibody (110) that binds to any tumor antigen present on the subject of a tumor cell associated with the cancer. The dimeric protein may not be an antibody. The specification does not describe the structure-identifying information e.g., amino acid sequences of such as the heavy and light chain variable domains or the six CDRs about the dimeric proteins or antibodies that bind to dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer wherein the dimeric comprises a first and second Fc polypeptides from human IgG1, IgG2, IgG3 or IgG4 wherein one or both Fc has triple substitutions E345R, E430G and S440Y or E345K, E430G and S440Y or E345R, E430S and S440Y or E345R, E430G and S440W. The specification does not describe a representative number of species falling with the scope of the genus or structure 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 dimeric protein or antibody themselves for a method for of increasing complement activation in a human subject.
When a patent claims a genus using functional language, e.g., tumor antigen present on the surface of a tumor cell associated with the cancer to define a desired result, “the specification must demonstrate that the applicant has made a generic invention that achieves the claimed result and do so by showing that the applicant has invented species sufficient to support a claim to the functionally-defined genus.” AbbVie Deutschland GmbH & Co., KG v. Janssen Biotech, Inc., 759 F.3d 1285, 1299 (Fed. Cir. 2014) (quoting Ariad, 598 F.3d at 1349).
The state of the art at the time the invention was made recognized 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. of record, Protein Engineering, Design & Selection 2009, 22:159-168; see, e.g., Discussion, PTO 892).
Similarly, Edwards et al., (of record, J Mol Biol. 2003 Nov 14;334(1): 103-118, 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 or epitope of such antigen (as held in AbbVie Deutschland GMBH v. Janssen Biotech, 111 USPQ2d 1780, 1790 (Fed. Cir. 2014).
As in Amgen, the pending claims of the instant case attempt to describe a genus of antibodies by describing something that is not an antibody, i.e. the antigen to which the antibody binds. Also analogous to Amgen, the fact that antigenic structures are known in detail would enable one of skill in the art to make antibodies meeting the binding limitations of the claims. As noted in Amgen, however, this is not enough to meet the written description requirement.
In AbbVie Deutschland GMBH v. Janssen Biotech, 111 USPQ2d 1780, 1790 (Fed. Cir. 2014), a claim drawn to a genus of antibodies having a recited binding affinity and binding specificity to a fully characterized antigen was found to be invalid for lack of written description such that it was not infringed by a subsequently disclosed antibody having all of the recited functional characteristics but a completely different structure (amino acid sequence). The Court held:
“It is true that functionally defined claims can meet the written description requirement if a reasonable structure-function correlation is established, whether by the inventor as described in the specification or known in the art at the time of the filing date... The asserted claims attempt to claim every fully human IL-12 antibody that would achieve a desired result, i.e., high binding affinity and neutralizing activity, and cover an antibody as different as Stelara®, whereas the patents do not describe representative examples to support the full scope of the claims. (AbbVie, 759 F.3d at 1298; 111 USPQ2d at 1791) (emphasis added).
Thus, the Amgen and the AbbVie decisions each support the finding that the detailed knowledge of one antibody structure does not reliably predict the structure of other antibodies that bind to the same antigen or epitope of an antigen and have the same effects. No structure-function relationship is established.
Regarding human subject (claim 103), the subject encompasses healthy subject and subject who has cancer (claim 122). There are no in vivo working example of administering any dimeric protein above to a healthy human subject. Thus, the claimed invention as a whole may not be adequately described where an invention is described solely in terms of its binding function and there is no described or art-recognized correlation or relationship between the structure of the invention and its function (see MPEP 2163).
Regarding oligomeric form (claim 119), the examiner agrees that the specification demonstrated in the Examples, the antibodies comprising the claimed mutations are able to oligomerize and form hexamers in solution. However, the term “hexamers” is not in the claim as oligomer encompass precipitate or clump together.
For these reasons, the rejection is maintained.
Claims 103-115, 117-120 and 122 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 method of increasing Complement Activation, the method comprising administering to a human subject in need thereof a therapeutically effective amount of a dimeric antibody protein, wherein the dimeric antibody protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
(a) the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain, does not reasonably provide enablement for the methods as set forth in claims 103-120 and 122. 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.
There are many factors considered when determining if the disclosure satisfies the enablement requirement and whether any necessary experimentation is undue. These factors include, but are not limited to: 1) nature of the invention, 2) state of the prior art, 3) relative skill of those in the art, 4) level of predictability in the art, 5) existence of working examples, 6) breadth of claims, 7) amount of direction or guidance by the inventor, and 8) quantity of experimentation needed to make or use the invention. In re Wands, 858 F.2d 731, 737, 8 USPQ2d 1400, 1404 (Fed. Cir. 1988).
Claim 103 encompasses a method for of increasing complement activation in a human subject, the method comprising administering to the subject a therapeutically effective amount of any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer,
wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain.
Claim 104 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acids at the positions corresponding to E345, E430, and S440 are R, G, and Y, respectively.
Claim 105 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acid at the position corresponding to E345, E430, and S440 in a human IgG1 heavy chain are R, G, and Y, respectively.
Claim 106 encompasses the method of claim 103, wherein, for one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are K, G, and Y, respectively.
Claim 107 encompasses the method of claim 103, wherein in one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are R, S, and Y, respectively.
Claim 108 encompasses the method of claim 103, wherein in one or both Fc polypeptides, the amino acids in the positions corresponding to E345, E430, and S440 are R, G, and W, respectively.
Claim 109 encompasses the method of claim 103, wherein the dimeric protein is an antibody.
Claim 110 encompasses the method of claim 109, wherein the antibody is any monoclonal antibody.
Claim 111 encompasses the method of claim 103, wherein each Fc polypeptide comprises at least the CH2 and CH3 regions of a human IgGl.
Claim 112 encompasses the method of claim 103, wherein one or both polypeptides of the dimer further comprises a region capable of covalent binding between said first and second polypeptides.
Claim 113 encompasses the method of claim 103, wherein one or both polypeptides of the dimer further comprises a hinge region of an immunoglobulin heavy chain.
Claim 114 encompasses the method of claim 103, wherein the first and second polypeptides of the dimer are interconnected via hinge region disulfide bonds.
Claim 115 encompasses the method of claim 103, wherein one or both polypeptides of the dimer comprise a full-length heavy chain constant region.
Claim 117 encompasses the method of claim 103, wherein the dimeric protein is a homodimer.
Claim 118 encompasses the method of claim 103, wherein the dimeric protein is any heterodimer.
Claim 119 encompasses the method of claim 103, wherein the dimeric protein is predominantly in oligomeric form in a phosphate buffer at a pH of about 6.8.
Claim 120 encompasses the method of claim 103, wherein the dimeric protein is predominantly in monomeric form at a pH of less than 6.0.
Claim 122 encompasses the method of claim 103, wherein the human subject has cancer.
Enablement is not commensurate in scope with claims as how to make and use any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer for a method of increasing complementation in a human subject encompassed by the claimed method.
Regarding any dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer, the specification discloses just IgG1 antibodies namely rituximab that binds to CD20, CD38 specific antibody 003 or EGFR specific antibody 2F8. The IgG1 antibody has triple mutation in the Fc at position E345R, E430G, and S440Y, numbering according to Eu as set forth in Kabat, see Example 26. The triple mutation E345R/E430G/S440Y can form non-covalent hexameric IgG complexes in solution at pH 6.8, see Examples 20, 25, 31.
However, three species of IgG1 antibodies are not representative of the genus of dimeric protein (claim 103), or antibody (claim 109 or monoclonal antibody (110) that binds to any and all tumor antigen present on the subject of a tumor cell associated with the cancer. The dimeric protein may not be an antibody. The specification does not teach the amino acid sequence of the heavy and light chain variable domains or the six CDRs about the dimeric proteins or antibodies that bind to any and all tumor antigen present on the surface of a tumor cell associated with the cancer wherein the dimeric comprises a first and second Fc polypeptides from human IgG1, IgG2, IgG3 or IgG4 wherein one or both Fc has triple substitutions E345R, E430G and S440Y or E345K, E430G and S440Y or E345R, E430S and S440Y or E345R, E430G and S440W to enable one of skill in the art to make and use without undue experimentation.
Even assuming the dimeric protein is an antibody, the state of the art at the time the invention was made recognized 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. of record, Protein Engineering, Design & Selection 2009, 22:159-168; see, e.g., Discussion, PTO 892).
Similarly, Edwards et al., (of record, J Mol Biol. 2003 Nov 14;334(1): 103-118, 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, 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 human subject (claim 103), the human subject now encompasses healthy subject and subject who has cancer (claim 122). There are no in vivo working example of administering any dimeric protein above to a healthy human subject.
Accordingly, one skilled in the art would need to resort to undue experimentation in a complex and unpredictable field in order to determine how to perform the invention as claimed.
Applicants’ arguments filed August 6, 2025 have been fully considered but are not found persuasive.
Applicant’s position is that claim 103 has been amended to be drawn to a method of increasing complement activation in a human subject, wherein the method comprises administering to the subject a dimeric protein having the recited amino acid residues at positions 345, 430, and 440, wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440.
Based on the knowledge and skill in the art at the relevant filing date, as well as the guidance and working data in the specification (see, e.g., Examples 26, 35, and 36), the skilled artisan would not have reasonably doubted that the claimed methods are fully enabled. It is well established that the enablement requirement is satisfied if one of ordinary skill in the art would reasonably accept the supporting disclosure as being enabling based on the teachings and/or data that is provided (In re Brana, 51 F.3d 1560, 1566, 34 USPQ2d 1436, 1441 (Fed. Cir. 1995)).
For at least the foregoing reasons, Applicant respectfully requests that the rejection be withdrawn.
In response, the amendment to claim 103 is acknowledged.
Amended claim 103 encompasses a method for of increasing complement activation in a human subject, the method comprising administering to the subject a therapeutically effective amount of any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer,
wherein the dimeric protein comprises a first Fc polypeptide and a second Fc polypeptide, each Fc polypeptide comprising at least CH2 and CH3 regions of human IgG1, IgG2, IgG3, or IgG4, wherein in one or both Fc polypeptides:
the amino acid in the position corresponding to E345 in a human IgG1 heavy chain is R or K.
(b) the amino acid in the position corresponding to E430 in a human IgG1 heavy chain is G or S, and
(c) the amino acid in the position corresponding to S440 in a human IgG1 heavy chain is Y or W, and wherein the numbering is according to the EU index as set forth in Kabat, and wherein complement activation is increased compared to complement activation induced by a reference dimeric protein, wherein the reference dimeric protein differs in amino acid sequence from the dimeric protein only by having an E at position 345, an E at position 430, and an S at position 440, wherein the positions correspond positions in a human IgG1 heavy chain.
Enablement is not commensurate in scope with claims as how to make and use any dimeric protein which binds to any tumor antigen present on the surface of a tumor cell associated with the cancer for a method of increasing complementation in a human subject encompassed by the claimed method.
Regarding any dimeric protein which binds to any and all tumor antigen present on the surface of a tumor cell associated with the cancer, the specification discloses just IgG1 antibodies, namely rituximab that binds to CD20, CD38 specific antibody 003 or EGFR specific antibody 2F8. The IgG1 antibody has triple mutation in the Fc at position E345R, E430G, and S440Y, numbering according to EU as set forth in Kabat, see Example 26. The triple mutation E345R/E430G/S440Y can form non-covalent hexameric IgG complexes in solution at pH 6.8, see Examples 20, 25, 31.
However, three species of IgG1 antibodies are not representative of the genus of dimeric protein (claim 103), or antibody (claim 109 or monoclonal antibody (110) that binds to any and all tumor antigen present on the subject of a tumor cell associated with the cancer. The dimeric protein may not be an antibody.
The specification does not teach the amino acid sequence of the heavy and light chain variable domains or the six CDRs about the dimeric proteins or antibodies that bind to any and all tumor antigen present on the surface of a tumor cell associated with the cancer and wherein the dimeric comprises a first and second Fc polypeptides from human IgG1, IgG2, IgG3 or IgG4 wherein one or both Fc has triple substitutions E345R, E430G and S440Y or E345K, E430G and S440Y or E345R, E430S and S440Y or E345R, E430G and S440W to enable one of skill in the art to make and use without undue experimentation.
Even assuming the dimeric protein is an antibody, the state of the art at the time the invention was made recognized 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. of record, Protein Engineering, Design & Selection 2009, 22:159-168; see, e.g., Discussion, PTO 892).
Similarly, Edwards et al., (of record, J Mol Biol. 2003 Nov 14;334(1): 103-118, 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, 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 human subject (claim 103), the human subject now encompasses healthy subject and subject who has cancer (claim 122). There are no in vivo working example of administering any dimeric protein above to a healthy human subject.
Accordingly, one skilled in the art would need to resort to undue experimentation in a complex and unpredictable field in order to determine how to perform the invention as claimed.
For these reasons, the rejection is maintained.
Conclusion
No claim is allowed.
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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