DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-19 are pending.
Election/Restrictions
Applicant's election of Group I, claims 1-5, in the reply filed on 10-17-25 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claims 6-19 have been withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10-17-25.
Claims 1-5 are under consideration.
Claim Rejections - 35 USC § 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.
Enablement
Claims 1-5 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 an antibody obtained from a transgenic rabbit, does not reasonably provide enablement for a bispecific antibody containing a “common antibody light chain” comprising a variable domain that has the amino acid sequence of SEQ ID NO: 1. 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 is drawn to a method of making a bispecific antibody comprising use of a common antibody light chain comprising a variable domain that has the amino acid sequence of SEQ ID NO: 1 or is a variant thereof.
Nature of the Invention
The only means of making the antibody disclosed in the specification is via a transgenic rabbit whose genome comprises a replacement of endogenous Ig VH gene segments and nucleic acid sequences encoding human VH gene segments. Specifically, the transgenic rabbit has a genome comprising a transgene comprising the humanized immunoglobulin light chain gene comprising 25 human immunoglobulin kappa light chain variable region (Vk) gene segments, a human JK4 gene segment, and a human Ck gene. The rabbit further comprises (1) a transgene comprising a humanized immunoglobulin heavy chain gene comprising 8 human VH gene segments, human JH1-JH6 gene segments, human Cmu-coding regions fused to human bcl2 coding sequence, and a human Cgamma gene, (2) transgenes comprising the human CD79alpha and CD79beta genes, and (3) loss-of-function mutations within the rabbit Cmu and rabbit Ck genes (pg 19, Example 1).
The state of the prior art:
The state or the art of how to prepare transgenic vector and how to produce transgenic rabbit by using the transgenic vector was well known in the art, however, the resulting phenotype of the transgenic rabbit was unpredictable before the effective filing date of the claimed invention.
The breadth of the claims:
The claims encompass any making bispecific antibodies from any animal. The bispecific antibody may be from one species or it may be chimeric. The bispecific antibody may be from a wild-type animal or a transgenic animal. The bispecific antibody may be a fragment or whole.
SEQ ID NO: 1 was well known as a human Ig kappa light chain V domain
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The level of skill:
The level of skill is high that require a researcher with a PhD degree.
The working examples and guidance provided:
The specification mentions the transgenic rabbits used for immunization and making humanized antibodies contained (1) a transgene derived from the rabbit immunoglobulin heavy chain gene, substituted with 8 human VH gene segments, human JH1-JH6 gene segment, human Cmu gene fused to human bcl2 gene, and human Cgamma gene; (2) a transgene derived from the rabbit immunoglobulin light chain gene, substituted with 25 human Vk gene segments, the proximal Vk gene segment fused to human Jk4 gene segment, and a human Ck gene; (3) transgenes derived from the human CD79a and CD79b genes; and (4) loss-of-function mutations within the rabbit Cmu and rabbit Ck genes. Rabbits were immunized with recombinant soluble antigen by alternating intramuscular and subcutaneous applications, blood was taken, and peripheral mononuclear cells were isolated, which were used as a source of antigen-specific B-cells in the B-cell cloning process. Rabbits were immunized using a plasmid expression vector coding for full-length antigen by intradermal application of vector DNA, blood was taken and peripheral mononuclear cells were isolated, which were used as a source of antigen-specific B-cells in the B-cell cloning process (Example 1, p. 19-20). Total RNA was prepared from B cell lysate and RTPCR was performed to obtain cDNA. The used antigen was the extracellular domain of TPBG (trophoblast glycoprotein, SEQ ID No. 11) and the resulting antibodies for the extracellular domain of TPBG are described as SEQ ID Nos. 12-14 (Example 4, p. 23). Anti-TPBG samples were added in a 1:2 dilution series to determine its binding to recombinant TPBG. Supernatant comprising anti-TPBG antibodies were added in a 1:2 dilution series to determine its binding to human TPBG in the human breast cancer tumor cell line MCF7. Table shows the binding to anti-TPBG Fab fragment to human TPBG (Example 5, p. 24).
The specification does not enable those of skill to make the bispecific antibody comprising a common antibody light chain comprising a variable domain that is SEQ ID NO: 1 in claim 1 without the transgenic rabbit in Example 1. However, the specification fails to provide adequate guidance how to make the transgenic rabbits. The specification fails to disclose what would be the phenotype of the transgenic rabbits, heterozygous or homozygous, comprising the humanized immunoglobulin light chain gene comprising 25 human immunoglobulin kappa light chain variable region (Vk) gene segments, a human IGKJ4 (Jk4) J gene segment, and a human Ck gene; and wherein the transgenic rabbit further comprises (1) a transgene comprising a humanized immunoglobulin heavy chain gene, comprising 8 human VH gene segments, human JH1-JH6 gene segments, human Cmu gene fused to human bcl2 coding sequence, and human Cgamma coding regions, (2) transgenes comprising the human CD79alpha and CD79beta genes, and (3) loss-of-function mutations within the rabbit Cmu and rabbit Ck genes.
In addition, the specification and the art at the time of filing do not teach how to make the bispecific antibody from a human or any wild-type animal. The specification does not teach how to make the bispecific antibody from a transgenic fish, amphibian, reptile, bird or mammal other than a transgenic rabbit. The specification does not teach how to make a bispecific antibody with a fish, amphibian, reptile, bird or mammalian heavy or light chain constant domain. The specification does not teach any bispecific antibodies that are “variants” as claimed.
The unpredictable nature of the art:
The claims read on a bispecific antibody with a common light chain containing SEQ ID NO: 1 obtained from a transgenic rabbit, heterozygous or homozygous, comprising the humanized immunoglobulin light chain gene comprising 25 human immunoglobulin kappa light chain variable region (Vk) gene segments, a human IGKJ4 (Jk4) J gene segment, and a human Ck gene; and wherein the transgenic rabbit further comprises (1) a transgene comprising a humanized immunoglobulin heavy chain gene, comprising 8 human VH gene segments, human JH1-JH6 gene segments, human Cmu- gene segment fused to human bcl2 gene segment, and a human Cgamma gene segment, (2) transgenes comprising the human CD79alpha and CD79beta gene, and (3) loss-of-function mutations within the rabbit Cmu and rabbit Ck gene.
The state of the art of transgenics before the effective filing date of the claimed invention held that the phenotype of transgenic animals was unpredictable. The resulting phenotype of the transgenic animals or transgenic rabbits was unpredictable before the effective filing date of the claimed invention. Patil 2011 (Indian Journal of Public Health research & Development, Vol. 2, No. 1, p. 106-109) reports limitations and issues concerned with transgenic animal including 1) Certain transgenic phenotypes may result in lethality that may compromise animals’ health status like impaired reproduction/lactation, immunodeficiency etc., 2) During development there may be physiologic compensation for the loss of a gene product in the knockout mouse, thus, complicating the interpretation of the phenotypic changes seen in transgenic animals, 3) One transgenic mouse will not be identical to another and strain differences will be a source of variability, and 4) Incorporation of new genetic material may alter the control of function of other genes. Khodarovich 2013 (Applied Biochemistry and Microbiology, Vol. 49, No. 9, pp. 711-722) points out that the effectiveness of DNA microinjection into the pronucleus of a zygote significantly differs for different animal species. It gives good results in mice, rabbits and pigs but is much less effective in large animals. This phenomenon can be due to 1) the smaller number of animals in a litter hampers collecting a sufficient amount of zygotes for injections, 2) it is difficult to "catch" the proper stage of zygote development, and 3) the pronuclei of large animals can often hardly be distinguished and the centrifugation of zygotes may require their visualization. Moreover, the efficiency of transgenic integration in large animals is less than in mice (e.g. p. 716, right column, 2nd full paragraph).
Selsby 2015 (ILAR Journal, Vol. 56, No. 1, p. 116-126) discusses different animal models for DMD. The mdx mice have much milder phenotype than that of human DMD patients. These animals continue to be mobile, experience very little limb muscle fibrosis or adiposity, exhibit no significant contractures, and have only a mildly reduced life span (e.g. p. 117, right column, last paragraph). Golden retriever muscular dystrophy (GRMD) dogs have a high degree of variability, despite an identical causative mutation. It is likely that at the root of this issue is variation in the expression of alternatively spliced dystrophin gene products and expression of resultant truncated translational products in the muscles of GRMD dogs, leading to great phenotypic range (e.g. p. 118, left column, 3rd paragraph). DMD rats showed muscle pathology consistent with DMD, however, there was large variation in severity between individual animals. The DMD rats have a phenotype similar to human DMA patients including fatty infiltration and a cardiac defect (e.g. p. 118, right column, 2nd paragraph). It is apparent that different species of non-human mammal could have diverse resulting phenotype with the same type of mutation and for the same species of non-human mammals, different type of mutations could result in various resulting phenotypes of transgenic non-human mammals.
Further, Maksimenko 2013 (Acta Naturae, Vol. 5, No. 1, p. 33-46) reports that “there have been numerous attempts at using animals in order to produce recombinant human proteins and monoclonal antibodies. However, it is only recently that the first two therapeutic agents isolated from the milk of transgenic animal, C1 inhibitor (Ruconest) and antithrombin (ATryn), appeared on the market” (e.g. Abstract). Microinjection (MI) is now used mainly to produce transgenic mice, rabbits and pigs because of the insufficient efficiency of the method due to the low frequency of incorporation of recombinant DNA into the genome and the availability of zygotes at the two pronuclear stages (e.g. p. 34, bridging left and right columns). “The adverse effects of the nuclear transfer (NT) techniques include a low in utero embryo survival rate and poor health of the newborn animals. This is attributed, among other things, to incomplete reprogramming of the somatic nucleus, resulting in impaired expression of several of the genes required for the proper progression of embryogenesis.” (e.g. p. 35, left column, 1st full paragraph). The site-specific transgenesis technology using embryonic stem (ES) cells has only been perfected for mice and rats. ES cell lines for farm animals have yet to be obtained (e.g. p. 35, left column, 2nd full paragraph). “The site at which the construct is integrated into the genome plays a crucial role in ensuring efficient transgene expression. Injected DNA is typically incorporated into the gene-poor regions, which are characterized by frequent DNA breaks. The chromatin in these regions typically exerts a negative influence on the expression of the transgene integrated nearby. In addition, several copies of the construct are typically integrated onto the same genome site, which can, in turn, lead to repression of transcription due to the formation of heterochromatin in repetitive sequences (e.g. bridging right column, p. 36 and left column, p. 37). There are difficulties and problems encountered by using technology of microinjection and somatic cell nuclear transfer (SCNT) to generate transgenic animals before the effective filing date of the claimed invention. The site-specific transgenesis technology using embryonic stem (ES) cells has only been perfected for mice and rats, and the site of integration of the transgene into the genome plays a crucial role in ensuring efficient transgene expression.
More recently, Yang 2016 (PNAS, 113(41), E6209-E6218, p. 1-10) reports generation of transgenic mice expressing either the ALS-associated mutant C71G or wild-type protein, and the mice expressing the mutant protein had relentless progression of motor neuron loss with concomitant progressive muscle weakness ending in paralysis and death. Unexpectedly, the acceleration of motor neuron degeneration precedes the accumulation of mutant PFN1 aggregates, which suggests that although mutant PFN1 aggregation may contribute to neurodegeneration, it does not trigger its onset (e.g. Abstract). Yang use two different promoters (Prp and Thy1.2) to generate transgenic lines expressing mutant PFN1 protein (C71G) and found that mutant PFN1 driven by the Thy1.2 promoter is expressed in the largest alpha motor neuron population, whereas the transgene expression is broader in Prp-PFN1C71G mice, including both motor and nonmotor neurons (e.g. p. 2, right column, 2nd paragraph). The Prp-PFN1C71G line did not develop any ALS phenotype up to the age of 700d. In contrast, all Thy1.2-PFN1C71G mice began to show slight weakness at an average age of ~350d and become paralyzed at 421d. Yang crossed the transgenic lines to produce homozygote mice and found that the cross within the Prp-PFN1C71G line did not yield any homozygotes, suggesting this genotype is lethal. However, Thy1.2-PFN1C71G homozygous mice resulted in a 50% increase in exogenous expression relative to the hemizygous mice, and the Thy1.2-PFN1C71G homozygous mice began to display weakness at ~150d and full paralysis at 321d, which represents a 25% reduction in survival relative to the Thy1.2-PFN1C71G hemizygous mice (e.g. p. 2, right column, last paragraph). It is apparent that different promoter driving the expression of the same mutant protein can result in different phenotype in the transgenic animal such as mice, and heterozygous (hemizygous) transgenic animal and homozygous transgenic animal can have different phenotype because of the site of expression and the level of the mutant protein expressed in the transgenic animal. The homozygous Prp-PFN1C71G transgenic mice resulted in lethal phenotype, however, the homozygous Thy1.2-PFN1C71G mice showed more severe ALS phenotype but not lethal phenotype.
In addition, Guo 2015 (Cell Research, Vol. 25, p. 767-768) points out “mosaic mutations and off-target effects caused by CRISPR/Cas9 have led to concerns about the efficiency and specificity of this new technique in non-human primates and other large animals” (p. 767, left column, 1st paragraph). Mosaic mutation may result from the prolonged expression of Cas9 mRNA, however, Cas9 protein also leads to mosaic mutations. Mosaic mutations may affect generation of animal models of genetic human diseases (e.g. p. 767, right column, last paragraph). Lee 2016 (Drug Discovery Today: Disease Models, Vol. 20, p. 13-20) reports that “considerable controversies such as off-target effects, germline transmission, efficient genotyping, and phenotyping needed to be validated in the GEMs that were produced by engineered nucleases…, there are still critical issues that might result in the misrepresentation of the genotype and phenotype of mice generated using engineered nucleases”. “Many investigators have optimistically presumed that the premature stop codon generated by the engineered nucleases immediately downstream of the start codon would result in the expression of truncated transcript that would be remarkably decreased by an RNA quality-control mechanism that selectively eliminates mutated mRNAs harboring premature stop codons, which is called nonsense-mediated mRNA decay (NMD) [63,64]. However, it is often disregarded that premature stop codons in the vicinity of the start codon are unable to induce NMD… Alternative splicing and exon skipping sometimes bypass premature stop codons, resulting in the formation of alternative proteins…, If these mutant or misfolded proteins are not degraded by ubiquitin-proteasome system (UPS)-dependent degradation or autophagy, they would have a high potential to play unexpected roles in vivo. Furthermore, unexpected proteins that seem to be produced from frame-shift alleles of GEM [66] can be generated by another biological phenomenon called translational reinitiation (TRI)” (e.g. p. 18, left column, 2nd paragraph). It appears that NMD and Tri mechanisms can generate truncated or aberrant RNA and proteins in genetically modified mouse model (GEM) and they could influence the resulting phenotype of the GEM. Similarly, those issues can also influence the resulting phenotype of other transgenic animals.
Further, Bradley 2013 (WO 2013/061098 A2) discussed problems encountered in producing humanizing antibodies via transgenic animal. “Although fully human antibodies could be generated, these models have several major limitations: (i) the size of the heavy and light chain gene (each several Mb) made it impossible to introduce the entire gene into these models. As a result the transgenic line recovered had a very limited repertoire of V-regions, most of the constant regions were missing and important distant enhancer regions were not included in the transgenes. (ii) the very low efficiency of generating the large insert transgenic lines and the complexity and time required to cross each of these into the heavy and light chain knockout strains and make them homozygous again, restricted the number of transgenic lines which could be analyzed for optimal expression. (iii) individual antibody affinities rarely reached those which could be obtained from intact (non-transgenic) animals (e.g. p. 1).
Zhu 2019 (Nature Communications, 10:1845, p. 1-13) discusses the challenges in humanizing the mouse genome. “Genomically humanized mouse strains with physiological levels of gene expression tend to have slower, milder phenotypes than transgenic overexpression models. However, these gene-targeted animals avoid overexpression artefacts, ectopic expression, and mutations resulting from random integration that can arise in transgenic models” (e.g. p. 1, last paragraph). “In one of the first large-scale genomic humanization studies of gene expression, the humanized region was almost 200 kb long, located in the alpha globin gene cluster. In all these cases, perhaps surprisingly, phenotypes ranged from relatively mild to apparently no different from wild-type mice (other than for the production of human proteins) (e.g. p. 6, right column, last paragraph). “The rule of the genome are not fully understood, nor are the full phenotypic consequences of creating mice with human genomic DNA… However, the design of a humanization strategy is far from routine, and a key question remains: how far to humanize (e.g. p. 7, right column, 2nd paragraph). “A critically important feature for gene regulation is the gene promoter, but currently no geed spatial definition of the promoters of most gene is available” (e.g. p. 8, left column, last paragraph). “One potential limitation of genomic humanization strategies that include the promoter regions is that even though human and mouse transcription factors are conserved, orthologues do not necessarily have identical amino-acid sequence or recognize identical motifs. Therefore, mouse proteins might not correctly regulate the transcription of human genes… humanized gene expression levels in mouse closely correlated with levels of the mouse orthologous gene, and not the human gene in human cells, in contrast to findings of the earlier study that suggested human expression levels were maintained” (e.g. p. 8, right column, 1st paragraph). In some instance, the 3’ UTR of a mouse gene overlaps the 5’ UTR of the adjacent gene, whereas in the human genome the two orthologues are separated by several kb. Therefore, the humanization strategy would be to replace the mouse gene with human gene but not to disrupt the regulation of downstream mouse genes (e.g. p. 8, right column, 2nd paragraph). “The phenotype of a genetic mouse model-transgenic or genomically humanized-is not always predictable” (e.g. p. 9, right column, last paragraph). It is apparent that the resulting phenotypes of genomically humanized mouse are different from that of the transgenic overexpression model. Different humanized mouse model shows different phenotypes and promoters for the human and mouse orthologous genes could be different and mouse proteins might not correctly regulate the transcription of human genes. Humanized gene expression levels in mouse closely correlated with levels of the mouse orthologous gene, and not the human gene in human cells. The phenotype of a genetic mouse model-transgenic or genomically humanized-is not always predictable.
The claims encompass a bispecific antibody obtained from heterozygous and homozygous transgenic rabbits expressing humanized Ig light chain and further expressing humanized Ig heavy chain and humanized B cell receptor. In view of the state of the art of transgenics including genomically humanized transgenic animal and transgenic animal overexpressing a transgene as discussed above, the resulting phenotype of the transgenic rabbits was unpredictable before the effective filing date of the claimed invention. The individual gene of interest (various nucleotide sequences encoding the different human proteins), promoter, enhancer, coding or non-coding sequences present in the transgene construct, the genetic background of the transgenic animals, the form (linear or circular) of the DNA molecule, the DNA concentration, the DNA copy number, different gene structures between human and the transgenic animal such as rabbit, the injection site, and the integration site of the transgene could determine the transgene expression in the transgenic animals and the resulting phenotype of the transgenic animals. Further, different promoter driving the expression of the same mutant protein can result in different phenotype in the transgenic animal such as rabbit, and heterozygous (hemizygous) transgenic animal and homozygous transgenic animal can have different phenotype because of the site of expression and the level of the mutant protein expressed in the transgenic animal. Generation of transgenic animal with desired phenotype is far from routine experimentation in view of the state of the art of transgenics. Absent specific guidance, one skilled in the art before the effective filing date of the claimed invention would not know how to produce transgenic rabbits and use them to make the bispecific antibody claimed.
The specification fails to provide adequate guidance and evidence for how the transgenic rabbits in Example 1 were generated. Total RNA was prepared from B cell lysate and RTPCR was performed to obtain cDNA. The used antigen was the extracellular domain of TPBG (trophoblast glycoprotein, SEQ ID No. 11) and the resulting antibodies for the extracellular domain of TPBG are described as SEQ ID Nos. 12-14 (Example 4, p. 23). Anti-TPBG samples were added in a 1:2 dilution series to determine its binding to recombinant TPBG. Supernatant comprising anti-TPBG antibodies were added in a 1:2 dilution series to determine its binding to human TPBG in the human breast cancer tumor cell line MCF7. Table shows the binding of anti-TPBG Fab fragment to human TPBG (Example 5, p. 24).
It is unclear whether the extracellular domain of TPBG is the antigen used in Example 1 to immunize the transgenic rabbit. It is unclear whether the antibody sequence of SEQ ID Nos. 12-14 are the antibodies produced from the immunization of the transgenic rabbit by using the extracellular domain of TPBG. It is also unclear whether the anti-TPBG sample and the anti-TPBG antibodies mentioned in example 5 are the antibodies of SEQ ID Nos. 12-14 of example 4. It is also unclear whether the antibodies of SEQ ID Nos. 12-14 are human antibodies against human Ig kappa light chain or human Ig heavy chain or both. The specification also fails to disclose whether the transgenic rabbit used for immunization is homozygous or heterozygous. The phenotype of homozygous transgenic rabbit could be different from the phenotype of heterozygous transgenic rabbit, and their resulting phenotypes were unpredictable before the effective filing date of the claimed invention. Absent specific guidance, one skilled in the art before the effective filing date of the claimed invention would not know how to generate transgenic rabbits with desired phenotype, and without a phenotype, one skilled in the art would not know how to use the transgenic rabbits, specifically in making a bispecific antibody having the structure of claim 1.
In addition, the specification and the art at the time of filing do not teach how to make the bispecific antibody from a human or any wild-type animal. The specification does not teach how to make the bispecific antibody from a transgenic fish, amphibian, reptile, bird or mammal other than a transgenic rabbit. The specification does not teach how to make a bispecific antibody with a fish, amphibian, reptile, bird or mammalian heavy or light chain constant domain. The specification does not teach any bispecific antibodies that are “variants” as claimed.
The amount of experimentation necessary:
One skilled in the art before the effective filing date of the claimed invention would require to identify and isolate embryonic stem cells of rabbit, prepare numerous different transgenic vectors comprising human immunoglobulin light chain gene segments, human immunoglobulin heavy chain gene segments, human Cmu-coding regions fused to human bcl2 coding sequence, human CD79alpha and CD79beta transgenes, and loss-of-function mutations within the rabbit Cmu and rabbit Ck gene, under the control of their various promoters, trial and error experimentation to generate the transgenic rabbit required to make the claimed bispecific antibody. Those skill would have to figure out how to use of various techniques including ES cell technology, microinjection of the transgenic vector into fertilized eggs, somatic cell nuclear transfer, and nuclease-mediated genome editing, identify and characterize numerous different transgenic rabbits comprising the transgenic vectors expressing humanized immunoglobulin genes, trial and error experimentation to identify the phenotypes of the generated transgenic rabbits, immunization of the generated transgenic rabbits, trial and error experimentation to determine whether any B cells of the peripheral blood from the transgenic rabbit expressed a humanized immunoglobulin kappa light chain and/or humanized Ig heavy chain, and trial and error experimentation to determine what would be the resulting phenotype of said transgenic rabbits after the immunization process. Then those of skill would have to determine whether the rabbit made a bispecific antibody having the structure of claim 1. Then those of skill would have to apply that to any other transgenic animal or to any wild-type animal.
For the reasons discussed above, it would have required undue experimentation for one skilled in the art before the effective filing date of the claimed invention to practice over the full scope of the invention claimed. This is particularly true given the nature of the invention, the state of the prior art, the breadth of the claims, the amount of experimentation necessary, the working examples provided and scarcity of guidance in the specification, the level of skilled artisan which is high, and the unpredictable nature of the art.
Written Description
Claims 1-5 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 applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
A) The specification lacks written description for the method of making a bispecific antibody of claim 1 which is recited above. The claims encompass any species of variable domains made from any animal. The bispecific antibody may be a fragment or whole. The bispecific antibody may be from one species or it may be chimeric. The bispecific antibody may be from a wild-type animal or a transgenic animal.
SEQ ID NO: 1 was well known as a human Ig kappa light chain V domain (see above).
The specification mentions the transgenic rabbits used for immunization contained (1) a transgene derived from the rabbit immunoglobulin heavy chain gene, substituted with 8 human VH gene segments, human JH1-JH6 gene segment, human Cmu gene fused to human bcl2 gene, and human Cgamma gene; (2) a transgene derived from the rabbit immunoglobulin light chain gene, substituted with 25 human Vk gene segments, the proximal Vk gene segment fused to human Jk4 gene segment, and a human Ck gene; (3) transgenes derived from the human CD79a and CD79b genes; and (4) loss-of-function mutations within the rabbit Cmu and rabbit Ck genes. Rabbits were immunized with recombinant soluble antigen by alternating intramuscular and subcutaneous applications, blood was taken, and peripheral mononuclear cells were isolated, which were used as a source of antigen-specific B-cells in the B-cell cloning process. Rabbits were immunized using a plasmid expression vector coding for full-length antigen by intradermal application of vector DNA, blood was taken and peripheral mononuclear cells were isolated, which were used as a source of antigen-specific B-cells in the B-cell cloning process (Example 1, p. 19-20). Total RNA was prepared from B cell lysate and RTPCR was performed to obtain cDNA. The used antigen was the extracellular domain of TPBG (trophoblast glycoprotein, SEQ ID No. 11) and the resulting antibodies for the extracellular domain of TPBG are described as SEQ ID Nos. 12-14 (Example 4, p. 23). Anti-TPBG samples were added in a 1:2 dilution series to determine its binding to recombinant TPBG. Supernatant comprising anti-TPBG antibodies were added in a 1:2 dilution series to determine its binding to human TPBG in the human breast cancer tumor cell line MCF7. Table shows the binding to anti-TPBG Fab fragment to human TPBG (Example 5, p. 24).
The specification lacks written description for making the rabbit or using the rabbit to obtain any bispecific antibody comprising a common antibody light chain comprising a variable domain that is SEQ ID NO: 1. The specification fails to provide adequate guidance and evidence for how the transgenic rabbits were generated because the specification fails to disclose what would be the phenotype of the transgenic rabbits, heterozygous or homozygous, comprising the humanized immunoglobulin light chain gene comprising 25 human immunoglobulin kappa light chain variable region (Vk) gene segments, a human IGKJ4 (Jk4) J gene segment, and a human Ck gene; and wherein the transgenic rabbit further comprises (1) a transgene comprising a humanized immunoglobulin heavy chain gene, comprising 8 human VH gene segments, human JH1-JH6 gene segments, human Cmu gene fused to human bcl2 coding sequence, and human Cgamma coding regions, (2) transgenes comprising the human CD79alpha and CD79beta genes, and (3) loss-of-function mutations within the rabbit Cmu and rabbit Ck genes.
In addition, the specification lacks written description for how to make the bispecific antibody from a human or any wild-type animal as broadly encompassed by claim 1. The specification does not teach how to make the bispecific antibody from a transgenic fish, amphibian, reptile, bird or mammal other than a transgenic rabbit as broadly encompassed by claim 1. The specification does not teach how to make a bispecific antibody with a fish, amphibian, reptile, bird or mammalian heavy or light chain constant domain as broadly encompassed by claim 1. The specification does not teach any bispecific antibodies that are “variants” as claimed as broadly encompassed by claim 1.
Accordingly, claim 1 lacks written description.
B) The specification lacks written description for a common light chain with 1-11 or 1-13 amino acid substitutions of SEQ ID NO: 1 as required in claim 3 or 4. The specification does not contemplate the concept. The specification does not teach any species within the genus. Therefore, the concept lacks written description.
Indefiniteness
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-5 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being incomplete for omitting essential steps and elements, such omission amounting to a gap between the steps and elements. See MPEP § 2172.01. The omitted steps are: immunizing a transgenic rabbit whose genome comprises [a replacement of endogenous VK gene segments with human VK gene segments?] with an antigen and obtaining a bispecific antibody comprising a human VK domain [and a human constant domain?] that binds the antigen [and something else?].
The art at the time of filing did not reasonably teach or suggest a bispecific antibody comprising a common light chain comprising a variable domain that has the amino acid sequence of SEQ ID NO: 1.
Conclusion
No claim is allowed.
Inquiry concerning this communication or earlier communications from the examiner should be directed to Michael C. Wilson who can normally be reached at the office on Monday through Friday from 9:30 am to 6:00 pm at 571-272-0738.
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Michael C. Wilson
/MICHAEL C WILSON/
Primary Examiner, Art Unit 1638