Patent Application
20250236682
The present invention relates to a novel antibody format having an antigen-binding site that specifically binds to a cancer surface antigen, and two Fc domains.
Antibody-based therapeutic agents and Fc fusion proteins are a group of clinically important drugs for patients with cancer, immune diseases, infectious diseases, and inflammatory diseases. ADCC (antibody-dependent cell-mediated cytotoxicity), ADCP (antibody-dependent cellular phagocytosis), and CDC (complement-dependent cytotoxicity), which are induced by the interaction between the antibody Fc domain and the innate immune system, play an important role in alleviating or treating symptoms of the disease.
Attempts are being made to maintain the bivalency of the antibody and to improve the effector function by increasing the number of Fc domains (Claudio Sustmann et al., MAbs. 2019; Dennis R Goulet et al., Proteins, 2020). Although these platforms confirmed improvements in binding ability to Fcγ receptors and ADCC, it is difficult to obtain homogeneous antibodies due to the complexity of production and purification. Attempts to improve the effector function by connecting the Fc domains of antibodies in tandem or constituting a large number of Fc domains are also currently underway (U.S. Patent Publication US 2020/0040084 A1). In this case, there is a disadvantage that permeability to the tissue may be significantly lowered due to the increase in the size or molecular weight of the antibody.
Accordingly, the present inventors studied to improve the function of the antibody and at the same time to solve the problems of the existing antibody format designed to comprise multiple Fc domains in tandem as described above. As a result, the present inventors developed a novel improved antibody format that enables Fc domains to be present on a cell surface antigen a maximum of four times compared to a natural human antibody, even though it has a molecular weight (approximately 150 kDa) similar to that of natural human immunoglobulin G (IgG).
In one aspect of the present invention, there is provided a fusion protein comprising an antigen-binding site, a first Fc domain or a variant thereof linked to a first linking position of the antigen-binding site, and a second Fc domain or a variant thereof linked to a second linking position of the antigen-binding site.
In another aspect of the present invention, there is provided a fusion protein comprising two antigen-binding sites linked in tandem (tandem two antigen-binding regions), a first Fc domain or a variant thereof linked to a first linking position of the tandem 2 antigen-binding sites, and a second Fc domain or a variant thereof linked to a second linking position of the tandem 2 antigen-binding sites. According to one embodiment, each of the two antigen-binding sites constituting the tandem 2 antigen-binding sites may be a sequence comprising a CDR sequence or a variable region that is each capable of binding to different epitopes of the same antigen or to different antigens, or a sequence consisting of a variable region.
In the fusion proteins described in the present disclosure, according to one embodiment, the antigen-binding site may be a sequence comprising a CDR sequence or a variable region of an antibody or a sequence consisting of a variable region. Therefore, the antigen-binding site may comprise a first peptide consisting of or comprising a light chain CDR sequence or a light chain variable region of an antibody, and a second peptide consisting of or comprising a heavy chain CDR sequence or a heavy chain variable region of an antibody. The first Fc domain and the second Fc domain may each be a dimer consisting of two peptide sequences. The first peptide of the antigen-binding site binds to a first Fc domain or a variant thereof, and the second peptide of the antigen-binding site binds to a second Fc domain or a variant thereof.
In the fusion proteins described in the present disclosure, according to another embodiment, the first Fc domain and the second Fc domain may be linked to each other through a covalent bond, non-covalent bond, or linker, or may not be linked to each other. In a preferred embodiment, the first Fc domain and the second Fc domain are not linked to each other.
According to embodiments of the present disclosure, the Fc domain may be an Fc domain of a wild-type immunoglobulin, and may comprise modifications for modulating the reactivity of the Fc domain to Fcγ receptors (FcγRs), ADCC or minimizing the formation of undesirable multimers of the Fc domain, for example amino acid substitutions. The Fc domain comprises CH2 and CH3 regions, and may comprise a CH4 region and/or a hinge region, and it should be interpreted that the Fc domain comprises Fc domain fragments that exhibit the function of the Fc domain.
According to embodiments of the present disclosure, an antigen-binding site and an Fc domain or a variant thereof may be joined either directly or through a linker. For example, an antigen-binding site and an Fc domain or a variant thereof may be connected with or without a linker between the N-terminus and the C-terminus, between the N-terminus and the N-terminus, or between the C-terminus and the C-terminus of each peptide molecule.
According to embodiments of the present disclosure, when an antigen-binding site and an Fc domain or a variant thereof is joined through a linker, the linker may be a commonly used pepetide linker. For example, the linker may be a peptide consisting of 1-70 amino acid residues, 2-60 amino acid residues, 2-50 amino acid residues, 2-40 amino acid residues, 2-30 amino acid residues, 3-50 amino acid residues, 3-40 amino acid residues, 3-30 amino acid residues, 2-28 amino acid residues, 2-26 amino acid residues, 2-24 amino acid residues, 2-22 amino acid residues, 2-20 amino acid residues, 2-18 amino acid residues, 2-16 amino acid residues, 2-14 amino acid residues, 2-12 amino acid residues, or 2-10 amino acid residues. The connection between a first Fc domain and an antigen-binding site, the connection between a second Fc domain and an antigen-binding site, or both may be achieved through a linker.
In another aspect of the present invention, there is provided a pharmaceutical composition for preventing or treating cancer, comprising the fusion protein as an active ingredient.
In another aspect of the present invention, there is provided nucleotides encoding the fusion protein, and a vector comprising the nucleotides, and a transformed cell into which the vector has been introduced.
In another aspect of the present invention, there is provided a method for treating or preventing cancer, comprising administering the fusion protein to a subject.
In another aspect of the present invention, there is provided a use of the fusion protein for the treatment of cancer.
Unlike wild type antibodies, the fusion protein having the novel antibody format of the present invention comprises one or two antigen-binding sites and two Fc domains. The two Fc domains are not directly linked to each other, but the two Fc domains are each independently linked to two different polypeptide chains constituting the antigen-binding site. Even though this novel antibody format has a size and molecular weight similar to that of human IgG, it can enable Fc domains to be present on a cell surface antigen a maximum of four times compared to a natural human antibody. Due to these properties, the fusion protein having the novel antibody format has improved affinity (avidity) for Fcγ receptors and can induce improved effector functions. Therefore, the fusion protein having the novel antibody format can be utilized for various purposes by replacing conventional antibodies.
As used herein, the term “fusion protein with two Fcs” or “antibody with two Fcs” refers to a fusion protein in which two Fc domains are independently joined to two polypeptide chains constituting the antigen-binding site. The two polypeptide chains constituting the antigen-binding site may be different from each other. For example, one of the two polypeptide chains constituting the antigen-binding site may be a sequence comprising or consisting of the light chain CDR sequence or light chain variable region of the antibody, or may be an scFv, and the other may be a sequence comprising or consisting of the heavy chain CDR sequence or heavy chain variable region of the antibody, or may be an scFv. In one embodiment, the fusion protein having the two Fc regions may comprise the sequence of a “humanized” form of a non-human antibody, which is a chimeric antibody comprising a human immunoglobulin comprising native CDRs. In addition, the fusion protein may comprise a “fully human antibody” or a portion of a “human antibody.” In addition, in one embodiment, the multispecific fusion protein or antigen binding domain may be a “monoclonal antibody” or a portion thereof.
As used herein, the term “antibody” refers to a substance that specifically binds to an antigen and causes an antigen-antibody reaction. In addition, the antibody is also referred to as immunoglobulin. The antibody may refer to any one selected from IgG, IgE, IgM, IgD, and IgA, and may be a subclass of IgG, such as IgG1, IgG2, IgG3, IgG4, IgA1, or IgA2. In addition, the antibody may be an agonistic antibody or an antagonistic antibody.
As used herein, the term “Fab” or “Fab region” refers to a region of an antibody that binds to an antigen. Conventional IgG generally comprises two Fab regions. Each Fab region typically consists of one variable region and one constant region of each heavy chain and light chain. Specifically, the variable region and the constant region of the heavy chain in the Fab region are the VH and CH1 regions, and the variable region and the constant region of the light chain in the Fab region are the VL and CL regions. VH, CH1, VL, and CL of the Fab region may be arranged in various ways to impart the antigen binding ability according to the present disclosure, including the CrossMab Fab technology in which VH and VL have an arrangement substituted for each other.
As used herein, the term “heavy chain” refers to a polypeptide chain of about 50 kDa to about 70 kDa. Here, the N-terminal portion comprises a variable region of at least about 120 to 130 amino acids, and the C-terminal portion comprises a constant region. The constant region may be one of five types: alpha (α), delta (δ), epsilon (ε), gamma (γ), and mu (μ). Here, α, δ, and γ comprise about 450 amino acids, and μ and ε comprise about 550 amino acids.
As used herein, the term “light chain” refers to a polypeptide chain of about 25 kDa. Here, the N-terminal portion comprises a variable region of at least about 100 to about 110 amino acids, and the C-terminal portion comprises a constant region. There are two types of light chain constant domains: kappa (κ) or lambda (λ). In addition, the constant region of the light chain is referred to as “CL”. The heavy chain C domains (CH domains) are numbered from N-terminus to C-terminus (e.g., CH1, CH2, CH3, etc.). The CL and a CH1 regions of any of these antibody classes may be used in the present disclosure. In certain embodiments, the CL and CH1 regions provided herein are of the IgG type (for example, IgG1).
As used herein, the term “Fc” or “Fc region” refers to the C-terminal region of an immunoglobulin heavy chain, including a native Fc region, a recombinant Fc region, and a variant Fc region. Therefore, Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, the last three constant region immunoglobulin domains of IgE and IgM, and the hinge present in the N-terminus of these domains. For IgA and IgM, the Fc may comprise a J chain. For IgG, the Fc comprises the immunoglobulin domains Cy2 (CH2) and Cy3 (CH3) and the hinge between Cy1 and Cy2. Although the interface of the Fc region may vary, the human IgG heavy chain Fc region is generally defined as comprising residues C226, P230, or A231 at the C-terminus, where numbering is according to the EU index. As used herein, “Fc polypeptide” or “Fc-derived polypeptide” refers to a polypeptide comprising all or part of an Fc region. In one embodiment, a variant Fc region may be in a form in which at least one amino acid, for example, about 1 to about 10 amino acids, or about 1 to about 5 amino acids, are substituted compared to the native sequence Fc region. In addition, the variant Fc region may have at least about 80% homology, at least about 90% homology, or at least about 95% homology to the native sequence Fc region.
As used herein, the term “Fv” or “Fv fragment” or “Fv region” is a polypeptide comprising the VL and VH domains of a single antibody.
As used herein, the term “single chain Fv” or “scFv” refers to an antibody fragment comprising the VH and VL domains of an antibody within a single polypeptide chain.
As used herein, the term “variable region” refers to an antibody region comprising one or more immunoglobulin domains encoded by any one of the VL (including Vkappa (VK) and Vlambda (VL)) and/or VH genes that constitute the light chain (including kappa and lambda) and heavy chain immunoglobulin loci, respectively. The light or heavy chain variable region (VL or VH) consists of a “framework” or “FR” region that includes three hypervariable regions referred to as “complementarity determining regions” or “CDRs”. As used herein, the term “antigen” refers to a structure capable of selectively binding to an antibody. A target antigen may be a polypeptide, carbohydrate, nucleic acid, lipid, hapten, or other naturally occurring compound or synthetic compound. Specifically, an antigen is a polypeptide and may be a protein present on or within a cell.
As used herein, the term “epitope” refers to an antigenic determinant and is a part on an antigen to which an antibody or polypeptide binds. A protein epitope may comprise amino acid residues that are directly involved in binding as well as amino acid residues that are effectively blocked by specific antigen-binding antibodies or peptides. It is the simplest form or smallest structural region of a complex antigen molecule that may bind to an antibody or receptor. The epitope may be linear or structural/conformational.
As used herein, the term “vector” refers to a material for transporting or expressing a nucleic acid sequence including a nucleic acid sequence encoding a multispecific fusion protein (for example, an antibody) described herein. Specifically, vectors include expression vectors, plasmids, phage vectors, viral vectors, episomes, and artificial chromosomes.
As used herein, the term “polynucleotide,” also referred to as “nucleic acid,” refers to a polymer of nucleotides of any length. Specifically, the polynucleotide may be DNA or RNA.
In one aspect of the present invention, there is provided an antibody comprising a plurality of Fc domains, characterized in that the ratio of the antigen-binding site and the Fc domain is 1:2 or 2:2. Specifically, the antibody may be a fusion protein comprising an antigen-binding site, a first Fc domain or a variant thereof, and a second Fc domain or a variant thereof.
Here, the antigen-binding site may consist of two different polypeptide chains. In addition, each polypeptide may be linked to a first Fc domain or a variant thereof, and a second Fc domain or a variant thereof.
Here, in one embodiment of the fusion protein, when the antigen-binding site comprises Fab, it may be a fusion protein in which the two Fc domains are bound to the C-terminus of the CH1 region of the heavy chain and the C-terminus of the constant region of the light chain, respectively. In addition, the Fc domain and Fab may be linked through a peptide linker.
In addition, in one embodiment of the fusion protein, when the antigen-binding site is Fv, it may be a fusion protein in which the two Fc domains are bound to the C-terminus of the variable region of the heavy chain and the C-terminus of the variable region of the light chain, respectively. In addition, the Fc domain and Fv may be linked through a peptide linker.
This novel antibody format or structure has a molecular weight similar to human IgG. In addition, the fusion protein may have an antigen binding affinity equivalent to that of a human IgG-based antibody. However, the antibody format enables Fc domains to be present on a cell surface antigen a maximum of four times compared to a natural human antibody. Due to these characteristics, the fusion protein may have increased affinity for Fcγ receptors, and may have increased effector functions compared to the wild type antibody. Each Fc domain bound to the fusion protein may have a similar level of Fc receptor (Fcγ receptor and FcRn) binding affinity as the Fc domain of an IgG-based antibody, but due to the avidity effect, the apparent binding affinity (apparent affinity) of the fusion protein to the Fc receptor (Fcγ receptor and FcRn) may be significantly increased compared to a human IgG antibody. In addition, the fusion protein has a similar level of thermal stability as that of an IgG-based antibody.
Specifically, the fusion protein may be a fusion protein comprising (a) an antigen-binding site consisting of a first polypeptide comprising at least one complementarity-determining region (CDR) sequence and a second polypeptide comprising at least one complementarity-determining region (CDR) sequence, wherein the first polypeptide and the second polypeptide form a dimer, and the antigen-binding site is capable of specifically binding to a target antigen, (b) a first Fc domain or a variant thereof that is a dimer consisting of two polypeptide sequences, one of which is joined to the first polypeptide of the antigen-binding site, and (c) a second Fc domain or a variant thereof that is a dimer consisting of two polypeptide sequences, one of which is joined to the second polypeptide of the antigen-binding site.
Here, the first polypeptide of the antigen-binding site may comprise CDR1, CDR2, and CDR3 of an antibody heavy chain, and the second polypeptide of the antigen-binding site may comprise CDR1, CDR2, and CDR3 of an antibody light chain. In addition, the first polypeptide of the antigen-binding site may further comprise a CH1 region of an antibody heavy chain, and/or the second polypeptide of the antigen-binding site may further comprise a constant region of an antibody light chain.
The specific structure of the fusion protein is described in more detail below.
Here, the antigen-binding site is capable of specifically binding to a protein expressed on the cell surface. Specifically, the antigen-binding site is capable of specifically binding to a cancer antigen.
In one embodiment, the antigen-binding site is capable of specifically binding to any one selected from the group consisting of PD-L1, EGFR, EGFRvIII, BCMA, CD22, CD25, CD30, CD33, CD37, CD38, CD52, CD56, CD123, c-Met (MET), DLL3, DR4, DR5, GD2, nectin-4, RANKL, SLAMF7, Trop-2, LIV-1, claudin 18.2, IL13α2, CD3, HER2, HER3, FGFR2, FGFR3, GPC3, ROR1, Folα, CD20, CD19, CTLA-4, VEGFR, NCAM1, ICAM-1, ICAM-2, CEACAM5, CEACAM6, carcinoembryonic antigen (CEA), CA-125, alphafetoprotein (AFP), MUC-1, MUC-16, PSMA, PSCA, epithelial tumor antigen (ETA), melanoma-associated antigen (MAGE), immature laminin receptor, TAG-72, HPV E6/E7, BING-4, calcium-activated chloride channel 2, cyclin-B1, 9D7, Ep-CAM, EphA2, EphA3, mesothelin, SAP-1, survivin, and virus-derived antigens.
A second antigen-binding site is also capable of specifically binding to any one antigen selected from the above group. According to one embodiment, the antigen to which a first antigen-binding site binds may be different from the antigen to which a second antigen-binding site binds. For example, the first antigen-binding site may comprise a sequence that specifically binds to HER2, and the second antigen-binding site may comprise a sequence that specifically binds to EGFR. In another embodiment, the first antigen-binding site may comprise a sequence that specifically binds to one epitope of an antigen, and the second antigen-binding site may comprise a sequence that specifically binds to a different epitope of the same antigen.
Here, the antigen-binding site may comprise a variable region that specifically binds to the antigen. Specifically, the variable region may include the heavy chain variable region and light chain variable region of any one antibody selected from the group consisting of cetuximab, panitumumab, necitumumab, imgatuzumab, depatuxizumab, losatuxizumab, etevritamab, AMG-595, atezolizumab, avelumab, durvalumab, trastuzumab, pertuzumab, onartuzumab, emibetuzumab, telisotuzumab, datopotamab, sacituzumab, rovalpituzumab, tarlatamab, belantamab, ladiratuzumab, codrituzumab, aprutumab, bemarituzumab, vofatamab, ramucirumab, rituximab, obinutuzumab, daratumumab, and 1C1(Clone name), but is not limited thereto.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to EGFR. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 175, H-CDR2 represented by SEQ ID NO: 176, and H-CDR3 represented by SEQ ID NO: 177 of cetuximab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 178, L-CDR2 represented by SEQ ID NO: 179, and L-CDR3 represented by SEQ ID NO: 180. As another example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 181, H-CDR2 represented by SEQ ID NO: 182, and H-CDR3 represented by SEQ ID NO: 183 of panitumumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 184, L-CDR2 represented by SEQ ID NO: 185, and L-CDR3 represented by SEQ ID NO: 186. As another example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 187, H-CDR2 represented by SEQ ID NO: 188, and H-CDR3 represented by SEQ ID NO: 189 of necitumumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 190, L-CDR2 represented by SEQ ID NO: 191, and L-CDR3 represented by SEQ ID NO: 192. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 193, H-CDR2 represented by SEQ ID NO: 194, and H-CDR3 represented by SEQ ID NO: 195 of imgatuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 196, L-CDR2 represented by SEQ ID NO: 197, and L-CDR3 represented by SEQ ID NO: 198. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 199, H-CDR2 represented by SEQ ID NO: 200, and H-CDR3 represented by SEQ ID NO: 201 of depatuxizumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 202, L-CDR2 represented by SEQ ID NO: 203, and L-CDR3 represented by SEQ ID NO: 204. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 199, H-CDR2 represented by SEQ ID NO: 205, and H-CDR3 represented by SEQ ID NO: 206 of losatuxizumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 202, L-CDR2 represented by SEQ ID NO: 203, and L-CDR3 represented by SEQ ID NO: 204.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to EGFRvIII. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 207, H-CDR2 represented by SEQ ID NO: 208, and H-CDR3 represented by SEQ ID NO: 209 of etevritamab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 210, L-CDR2 represented by SEQ ID NO: 211, and L-CDR3 represented by SEQ ID NO: 212. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 213, H-CDR2 represented by SEQ ID NO: 214, and H-CDR3 represented by SEQ ID NO: 215 of AMG-595, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 210, L-CDR2 represented by SEQ ID NO: 216, and L-CDR3 represented by SEQ ID NO: 217.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to PD-L1. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 218, H-CDR2 represented by SEQ ID NO: 219, and H-CDR3 represented by SEQ ID NO: 220 of atezolizumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 221, L-CDR2 represented by SEQ ID NO: 222, and L-CDR3 represented by SEQ ID NO: 223. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 224, H-CDR2 represented by SEQ ID NO: 225, and H-CDR3 represented by SEQ ID NO: 226 of avelumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 227, L-CDR2 represented by SEQ ID NO: 228, and L-CDR3 represented by SEQ ID NO: 229. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 230, H-CDR2 represented by SEQ ID NO: 231, and H-CDR3 represented by SEQ ID NO: 232 of durvalumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 233, L-CDR2 represented by SEQ ID NO: 234, and L-CDR3 represented by SEQ ID NO: 235.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to HER2. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 21, H-CDR2 represented by SEQ ID NO: 22, and H-CDR3 represented by SEQ ID NO: 23 of trastuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 24, L-CDR2 represented by SEQ ID NO: 25, and L-CDR3 represented by SEQ ID NO: 26. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 33, H-CDR2 represented by SEQ ID NO: 34, and H-CDR3 represented by SEQ ID NO: 35 of pertuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 36, L-CDR2 represented by SEQ ID NO: 37, and L-CDR3 represented by SEQ ID NO: 38.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to c-Met. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 236, H-CDR2 represented by SEQ ID NO: 237, and H-CDR3 represented by SEQ ID NO: 238 of onartuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 239, L-CDR2 represented by SEQ ID NO: 240, and L-CDR3 represented by SEQ ID NO: 241. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 242, H-CDR2 represented by SEQ ID NO: 243, and H-CDR3 represented by SEQ ID NO: 244 of emibetuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 245, L-CDR2 represented by SEQ ID NO: 246, and L-CDR3 represented by SEQ ID NO: 247. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 248, H-CDR2 represented by SEQ ID NO: 249, and H-CDR3 represented by SEQ ID NO: 250 of telisotuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 251, L-CDR2 represented by SEQ ID NO: 252, and L-CDR3 represented by SEQ ID NO: 253.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to Trop-2. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 254, H-CDR2 represented by SEQ ID NO: 255, and H-CDR3 represented by SEQ ID NO: 256 of datopotamab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 257, L-CDR2 represented by SEQ ID NO: 258, and L-CDR3 represented by SEQ ID NO: 259. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 260, H-CDR2 represented by SEQ ID NO: 261, and H-CDR3 represented by SEQ ID NO: 262 of sacituzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 263, L-CDR2 represented by SEQ ID NO: 264, and L-CDR3 represented by SEQ ID NO: 265.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to DLL3. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 266, H-CDR2 represented by SEQ ID NO: 267, and H-CDR3 represented by SEQ ID NO: 268 of rovalpituzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 269, L-CDR2 represented by SEQ ID NO: 270, and L-CDR3 represented by SEQ ID NO: 271. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 272, H-CDR2 represented by SEQ ID NO: 273, and H-CDR3 represented by SEQ ID NO: 274 of tarlatamab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 275, L-CDR2 represented by SEQ ID NO: 276, and L-CDR3 represented by SEQ ID NO: 277.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to BCMA. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 278, H-CDR2 represented by SEQ ID NO: 279, and H-CDR3 represented by SEQ ID NO: 280 of belantamab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 281, L-CDR2 represented by SEQ ID NO: 282, and L-CDR3 represented by SEQ ID NO: 283.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to LIV-1. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 284, H-CDR2 represented by SEQ ID NO: 285, and H-CDR3 represented by SEQ ID NO: 286 of ladiratuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 287, L-CDR2 represented by SEQ ID NO: 288, and L-CDR3 represented by SEQ ID NO: 289.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to GPC-3. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 99, H-CDR2 represented by SEQ ID NO: 100, and H-CDR3 represented by SEQ ID NO: 101 of codrituzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 102, L-CDR2 represented by SEQ ID NO: 103, and L-CDR3 represented by SEQ ID NO: 104.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to FGFR2. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 290, H-CDR2 represented by SEQ ID NO: 291, and H-CDR3 represented by SEQ ID NO: 292 of aprutumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 293, L-CDR2 represented by SEQ ID NO: 294, and L-CDR3 represented by SEQ ID NO: 295. In addition, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 296, H-CDR2 represented by SEQ ID NO: 297, and H-CDR3 represented by SEQ ID NO: 298 of bemarituzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 299, L-CDR2 represented by SEQ ID NO: 300, and L-CDR3 represented by SEQ ID NO: 301.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to FGFR3. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 302, H-CDR2 represented by SEQ ID NO: 303, and H-CDR3 represented by SEQ ID NO: 304 of vofatamab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 305, L-CDR2 represented by SEQ ID NO: 306, and L-CDR3 represented by SEQ ID NO: 307.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to VEGFR2. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 308, H-CDR2 represented by SEQ ID NO: 309, and H-CDR3 represented by SEQ ID NO: 310 of ramucirumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 311, L-CDR2 represented by SEQ ID NO: 312, and L-CDR3 represented by SEQ ID NO: 313.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to CD20. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 314, H-CDR2 represented by SEQ ID NO: 315, and H-CDR3 represented by SEQ ID NO: 316 of rituximab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 317, L-CDR2 represented by SEQ ID NO: 318, and L-CDR3 represented by SEQ ID NO: 319. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 320, H-CDR2 represented by SEQ ID NO: 321, and H-CDR3 represented by SEQ ID NO: 322 of obinutuzumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 323, L-CDR2 represented by SEQ ID NO: 324, and L-CDR3 represented by SEQ ID NO: 325.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to CD38. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 326, H-CDR2 represented by SEQ ID NO: 327, and H-CDR3 represented by SEQ ID NO: 328 of daratumumab, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 329, L-CDR2 represented by SEQ ID NO: 330, and L-CDR3 represented by SEQ ID NO: 331.
As a specific example of the present invention, it may include an antigen-binding site that specifically binds to EphA2. For example, it may comprise a heavy chain variable region comprising H-CDR1 represented by SEQ ID NO: 157, H-CDR2 represented by SEQ ID NO: 158, and H-CDR3 represented by SEQ ID NO: 159 of 1C1, and may comprise a light chain variable region comprising L-CDR1 represented by SEQ ID NO: 160, L-CDR2 represented by SEQ ID NO: 161, and L-CDR3 represented by SEQ ID NO: 162.
Table 1 below shows the CDR sequences of non-limiting exemplary antibodies with anticancer efficacy that may be used in specific examples of the present invention.
As antigens to which the antigen-binding site described herein may specifically bind, the following non-limiting substances may be exemplified.
“Epidermal growth factor receptor (EGFR)”: It is a cell membrane receptor that regulates cell growth, division, survival, and death. In various cancers, the expression of EGFR is increased in tumor tissues. It is known that tumor tissues with the increased EGFR are invasive, metastatic, and highly resistant to anticancer agents. In one embodiment, the substance that inhibits EGFR may be cetuximab, panitumumab, necitumumab, imgatuzumab, depatuxizumab, or losatuxizumab, but is not limited thereto.
“Epidermal growth factor receptor variant 3 (EGFRvIII)”: It is a mutation in which exons 2 to 7 of EGFR are deleted. It is mainly reported in glioblastoma multiforme, and most patients with EGFRvIII-positive mutation have a poor prognosis. In one embodiment, the substance that inhibits EGFRvIII may be cetuximab, panitumumab, necitumumab, imgatuzumab, depatuxizumab, losatuxizumab, etevritamab, or AMG-595, but is not limited thereto.
Programmed death-ligand 1 (PD-L1)”: It is a protein overexpressed on the surface of cancer cells. It is a major cancer-specific antigen that plays an important role in inducing exhaustion and apoptosis of T cells and acquiring immune tolerance in cancer cells. In one embodiment, PD-L1 targeting anticancer antibody may be atezolizumab, avelumab, and durvalumab, but is not limited thereto.
“HER-2/neu (human epidermal growth factor receptor 2): It regulates cell proliferation through activation of PI3K/AkT. It is known that it is overexpressed in metastatic breast cancer and ovarian cancer, etc., and induces resistance against anticancer agents. The HER2/neu targeting anticancer agent may be trastuzumab or pertuzumab, but is not limited thereto.
“c-Met (mesenchymal-epithelial transition factor)”: It is a hepatocyte growth factor receptor. Its amplification or mutation is frequently reported in cancer cells, and it is known to promote tumor growth, metastasis, and malignancy. Specifically, the inhibitor of the protein may be onartuzumab, emibetuzumab, or telisotuzumab, but is not limited thereto.
“Trop-2 (tumor-associated calcium signal transducer 2)”: It is a cellular glycoprotein related to cancer cell growth and proliferation. It is known to be specifically overexpressed in non-small cell lung cancer and breast cancer. Specifically, the antibody targeting the protein may be datopotamab or sacituzumab, but is not limited thereto.
“DLL3 (delta-like ligand 3)”: It is a major cancer target antigen known to be expressed in approximately 85% of small cell lung cancer patients. Specifically, the antibody targeting the protein may be rovalpituzumab or tarlatamab, but is not limited thereto.
“BCMA (B-cell maturation antigen)”: It is an important factor in the survival and proliferation of myeloma cells and is a clinically proven target for treatment of multiple myeloma. Specifically, the antibody targeting the protein may be belantamab, but is not limited thereto.
“LIV-1 (zinc transporter ZIP6)”: It is a highly cancer-specific antigen overexpressed in breast cancer. Specifically, the antibody targeting the protein may be ladiratuzumab, but is not limited thereto.
“GPC-3 (glypican-3)”: It is a highly cancer-specific antigen that is specifically overexpressed in liver cancer. Specifically, the antibody targeting the protein may be codrituzumab, but is not limited thereto.
“FGFR (fibroblast growth factor receptor)”: It is a receptor for fibroblast growth factor (FGF), which regulates various biological processes including cell growth, differentiation, and migration. The FGFR gene is easily mutated, and these variants are commonly observed in breast cancer, uterine cancer, ovarian cancer, cervical cancer, and the like. The four FGFR genes are made of seven signaling receptors, of which FGFR2 and FGFR3 are highly cancer-specific antigens. The antibody targeting FGFR2 or FGFR3 may be aprutumab, bemarituzumab, or vofatamab, but is not limited thereto.
“Vascular endothelial growth factor receptor (VEGFR)”: It is a cell membrane receptor for a vascular endothelial growth factor that induces angiogenesis. The VEGFR inhibitor inhibits tumor growth and metastasis by inhibiting angiogenesis. In one embodiment, the VEGFR inhibitor may be ramucirumab, but is not limited thereto.
“CD20 (B lymphocyte antigen CD20)”: It is a protein expressed on the surface of B cells, which is used as a target protein for the treatment of B cell lymphoma. The CD20 inhibitor may be rituximab or obinutuzumab, but is not limited thereto.
“CD38 (cluster of differentiation 38)”: It is a protein that acts as a signal transduction receptor in immune cells and regulates cell proliferation and death. The inhibitor targeting the protein may be daratumumab, but is not limited thereto.
“EphA2 (EPH receptor A2)”: It is overexpressed in cancer cells and has a significant impact on the growth and metastasis of cancer cells. The antibody targeting the protein may be 1C1, but is not limited thereto.
The antigen-binding site that specifically binds to the antigens exemplified above may include CDR sequences as exemplified below.
Table 2 below shows the nucleotide sequence and the polypeptide sequence of an exemplary signal sequence for efficient expression of the fusion proteins according to various embodiments. When the above antibodies are expressed in mammalian cells, SEQ ID NO: 333 may be used as the signal sequence, but is not limited thereto.
Table 3 below shows the variable region polypeptide sequences of anticancer antibodies, which are described as antigen-binding sites of various fusion proteins described herein. The fusion proteins according to exemplary embodiments may comprise or consist of these variable region polypeptides.
tuzumab
atamab
indicates data missing or illegible when filed
Table 4 below shows the nucleotide sequences encoding variable regions of anticancer antibodies, which are described as antigen-binding sites of various fusion proteins described herein.
CATGGAAT
amab
indicates data missing or illegible when filed
Here, the above-described first Fc domain and the second Fc domain may each be an Fc region of an immunoglobulin. The Fc region of an immunoglobulin may be an Fc domain variant as well as a wild type Fc domain. Here, the Fc region may be an Fc region of IgG, IgA, IgE, IgD), or IgM.
As used herein, the term “Fc domain variant” may refer to a form which is different from the wild type Fc domain in terms of glycosylation pattern, has a high level of specific glycan species as compared with the wild type Fc domain, a low level of specific glycan species as compared with the wild type Fc domain, or a deglycosylated form. In addition, an aglycosylated Fc domain is included therein. The Fc domain or a variant thereof may be adapted to have an adjusted number of sialic acids, fucosylations, or other types of glycosylations, through modulation of culture conditions or genetic manipulation of a host cell.
In addition, glycosylation of the Fc domain of an immunoglobulin may be modified by conventional methods such as chemical methods, enzymatic methods, and genetic engineering methods using microorganisms. In addition, the Fc domain variant may be in a mixed form of respective Fc regions of immunoglobulin IgG, IgA, IgE, IgD, or IgM. In addition, the Fc domain variant may be a form in which some amino acids of the Fc domain are substituted with other amino acids.
An “amino acid” introduced by the substitution and/or addition may be any one selected from the group consisting of lysine (K), alanine (A), arginine (R), asparagine (N), aspartic acid (D), cysteine (C), glutamine (Q), glutamic acid (E), glycine (G), histidine (H), isoleucine (I), leucine (L), methionine (M), phenylalanine (F), proline (P), serine (S), threonine (T), tryptophan (W), tyrosine (Y), and valine (V).
In one embodiment, the variant of the Fc region may be a form in which amino acids 239 and/or 332 of the CH2 region are substituted with other amino acids (see Kabat numbering system). Specifically, S239 may be substituted with an amino acid other than S, and specifically, S239 may be substituted with S239D. In addition, 1332 may be substituted with an amino acid other than I, and specifically, I332 may be substituted with I332E.
In addition, the Fc region may include a variant or structure of a knob, or a variant or structure of a hole.
As used herein, the term “knob-into-hole” refers to an Fc heterodimerization strategy for producing antibodies that specifically bind to different regions, such as bispecific antibodies, multispecific antibodies, or heterodimeric antibodies. Generally, this technique involves introducing a knob mutation at the interface of a first polypeptide (e.g., the first CH3 domain of a first antibody heavy chain) and a corresponding hole mutation at the interface of a second polypeptide (e.g., the second CH3 domain of a second antibody heavy chain), such that a knob may be placed within the hole to promote heterodimer formation and prevent homodimer formation.
The ‘knob’ variant is constructed by replacing small amino acid side chains from the interface of the first polypeptide (e.g., the first CH3 domain of the first antibody heavy chain) with larger side chains (e.g., arginine, phenylalanine, tyrosine, or tryptophan). The complementary ‘hole’ variant of the same or similar size to the knob is created by replacing large amino acid side chains at the interface of the second polypeptide (e.g., the second CH3 domain of the second antibody heavy chain) with smaller side chains (e.g., alanine, serine, valine, or threonine). The knob and hole may be created by altering the nucleic acid encoding the polypeptide, for example, by site-directed mutagenesis, or by peptide synthesis.
Examples of variants of the Fc region that promote the formation of a heterodimer may include those described in WO2014084607A1 and WO2018059502A1, etc. The disclosures of WO2014084607A1 and WO2018059502A1 are incorporated herein by reference. WO2014084607A1 describes, for example, mutations in the CH3 domain that may comprise (a-1) tryptophan (W) substituted at Lys409 of one CH3 domain that interacts with valine (V) substituted at Asp399 and threonine (T) substituted at Phe405 of another CH3 domain; and (a-2) serine (S) substituted at Tyr349 of one CH3 domain that interacts with tryptophan (W) substituted at Glu357 of another CH3 domain, and in addition, may further comprise (b-1) glutamic acid (E) substituted at Lys360 of one CH3 domain that interacts with arginine (R) substituted at Gln347 of another CH3 domain; and (b-2) glutamic acid (E) substituted at Gln347 and glutamic acid substituted at Lys360 of one CH3 domain that interact with arginine (R) substituted at Gln347 of another CH3 domain. Here, the position of the amino acid residue follows the EU index. WO2018059502A1, for example, describes mutations in the Fc domain including one or more mutations selected from a)-e), respectively: a) L351G, L351Y, L351V, L351P, L351D, L351E, L351K, or L351W; b) T366L, T366P, T366W, or T366V; c) D399C, D399N, D399I, D399G, D399R, D399T, or D399A; d) Y407L, Y407A, Y407P, Y407F, Y407T, or Y407H; and e) K409C, K409P, K409S, K409F, K409V, K409Q, or K409R. Here, the position of the amino acid residue follows the EU index.
The fusion protein may comprise polypeptide chains represented by the following structural formulas (I), (II), (III), and (IV), respectively:
N′—X-(L1)n-A-C′ (I);
N′—Y-(L2)m-B—C′ (II);
N′—C—C′ (III); and
N′-D—C′ (IV)
Specifically, X is a first polypeptide sequence of the antigen-binding site, which comprises heavy chain CDR1, CDR2, and CDR3 sequences of an antibody that specifically binds to a first antigen, or a heavy chain variable region of an antibody that specifically binds to a first antigen; Y is a second polypeptide sequence of the antigen-binding site, which comprises light chain CDR1, CDR2, and CDR3 sequences of an antibody that specifically binds to a first antigen, or a light chain variable region of an antibody that specifically binds to a first antigen; and X and Y pair with each other to form the antigen-binding site (a) that specifically binds to an antigen.
According to one embodiment, the CH3 region may be mutated to minimize the interaction between A and B, and between C and D and promote the formation of a heterodimeric Fc between A and C, and between B and D. Specifically, the Fc domain monomer comprises a knob variant or a hole variant that promotes the formation of an Fc heterodimer (heterodimeric Fc); or the Fc domain monomer may comprise a variant that promotes the formation of a heterodimer by electrostatic steering mechanism.
According to one embodiment, X in the structural formula (I) may further comprise a heavy chain CH1 region, and/or Y in the structural formula (II) may further comprise a light chain constant region.
In addition, the fusion protein may comprise polypeptide chains represented by the following structural formulas (I′), (II′), (III), and (IV):
N′—VD1-(L3)p-X-(L1)n-A-C′ (I′);
N′—VD2-(L4)q-Y-(L2)m-B—C′ (II′);
N′—C—C′ (III); and
N′-D-C′ (IV)
According to one embodiment, the CH3 region may be mutated to minimize the interaction between A and B, and between C and D and promote the formation of a heterodimeric Fc between A and C, and between B and D. Specifically, the Fc domain monomer comprises a knob variant or a hole variant that promotes the formation of an Fc heterodimer (heterodimeric Fc); or the Fc domain monomer may comprise a variant that promotes the formation of a heterodimer by electrostatic steering mechanism.
According to one embodiment, the heavy chain variable region may further comprise a heavy chain CH1 region. In addition, the light chain variable region may further comprise a light chain constant region.
In the structures of the fusion proteins described herein, the binding between X and Y may be achieved i) through a disulfide bond formed by Cys present in CH1 and a light chain constant region, ii) through a disulfide bond formed by Cys present in a heavy chain variable region and a light chain variable region, or iii) through a disulfide bond formed by Cys present in CH1 and a light chain constant region, and a disulfide bond formed by Cys present in a heavy chain variable region and a light chain variable region.
Specifically, the binding between X and Y may be formed by a disulfide bond present between CH1233 and CL214 based on Kabat numbering system. In addition, X and Y may further comprise Cys through amino acid substitution. Examples of such variants may include mutations in the variable region, and specifically may include mutations at 105C of VH and 43C of VL, or mutations at 44C of VH and 100C of VL based on Kabat numbering system. In one embodiment, the mutation may be Q105C of VH and A43C of VL. In addition, in one embodiment, the mutation may be G44C of VH and Q100C of VL. In addition, examples of variants in the constant region may include mutations at 122C of CH1 and 121C of CL based on Kabat numbering system. In one embodiment, the mutation may be F122C of CH1 and S121C of CL.
The hinge is a hinge region derived from immunoglobulins. In one embodiment, the antibody hinge region is an IgG hinge region. The IgG hinge region provided herein may be selected, for example, from antibody hinge regions of various IgG subtypes. The table below lists exemplary IgG subtypes with core hinge sequences that may be included in the flexible peptide regions provided herein. In addition, at least one Cys may exist within the hinge. Specifically, 1, 2, or 3 Cys may exist within the hinge.
The hinge may be modified to delete disulfide bonds or introduce additional disulfide bonds.
In addition, the linkers L1 and L2 may each comprise 1 to about 70 amino acids. According to one exemplary embodiment, L1 and L2 may each comprise about 5 to about 60 amino acids, about 10 to about 50 amino acids, about 15 to about 40 amino acids, or about 20 to about 30 amino acids. According to another exemplary embodiment, for example, L1 and L2 may each be a peptide consisting of 1-70 amino acid residues, 2-60 amino acid residues, 2-50 amino acid residues, 2-40 amino acid residues, 2-30 amino acid residues, 3-50 amino acid residues, 3-40 amino acid residues, 3-30 amino acid residues, 2-28 amino acid residues, 2-26 amino acid residues, 2-24 amino acid residues, 2-22 amino acid residues, 2-20 amino acid residues, 2-18 amino acid residues, 2-16 amino acid residues, 2-14 amino acid residues, 2-12 amino acid residues, or 2-10 amino acid residues. Specifically, L1 and L2 may include the amino acid sequence of (G4S)o (where o is an integer of 1 to 5) in Table 6 below, but are not limited thereto. In addition, L1 and L2 may have different amino acid sequences. In addition, here, L1 and L2 may comprise at least one Cys. In addition, a disulfide bond may be formed through Cys present in L1 and L2.
In addition, the linkers L3 and L4 may each comprise 1 to about 30 amino acids. According to one exemplary embodiment, L3 and L4 may each comprise about 5 to about 25 amino acids, about 10 to about 20 amino acids, or about 15 amino acids. According to another exemplary embodiment, L3 and L4 may each be a peptide consisting of 2-30 amino acid residues, 2-25 amino acid residues, 2-20 amino acid residues, 2-15 amino acid residues, 3-30 amino acid residues, 2-28 amino acid residues, 2-26 amino acid residues, 2-24 amino acid residues, 2-22 amino acid residues, 2-20 amino acid residues, 2-18 amino acid residues, 2-16 amino acid residues, 2-14 amino acid residues, 2-12 amino acid residues, or 2-10 amino acid residues. Specifically, L3 and L4 may include the amino acid sequence of (G4S)o (where o is an integer of 1 to 5) in Table 6 above, but are not limited thereto. In addition, L3 and L4 may have different amino acid sequences.
i) Fusion Protein in which Antigen-Binding Site is Fab
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ii) Fusion Protein in which Antigen-Binding Site is Fv
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iii) Fusion Protein in which Antigen-Binding Site is Fab
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In another aspect of the present invention, there is provided a pharmaceutical composition for preventing or treating cancer, comprising the fusion protein as an active ingredient.
Here, cancer may be any one selected from the group consisting of gastric cancer, liver cancer, lung cancer, large intestine cancer, breast cancer, prostate cancer, skin cancer, bone cancer, multiple myeloma, glioma, ovarian cancer, pancreatic cancer, cervical cancer, thyroid cancer, laryngeal cancer, acute myeloid leukemia, chronic myeloid leukemia, acute lymphoblastic leukemia, chronic lymphoblastic leukemia, brain tumor, neuroblastoma, retinoblastoma, head and neck cancer, salivary gland cancer, and lymphoma.
In another aspect of the present invention, there is provided a polynucleotide encoding a polypeptide of the structural formula (I), (II), (III), and/or (IV).
In another aspect of the present invention, there is provided a polynucleotide encoding a polypeptide of the structural formula (I′), (II′), (III), and/or (IV).
The polynucleotide may further comprise a nucleic acid encoding a signal sequence or a leader sequence. As used herein, the term “signal sequence” refers to a signal peptide that directs secretion of a target protein. The signal peptide is translated and then cleaved in a host cell. Specifically, the signal sequence is an amino acid sequence that initiates migration of a protein across the endoplasmic reticulum (ER) membrane.
The signal sequences are well known in the art for their characteristics. Such signal sequences typically comprise 16 to 30 amino acid residues, and may comprise more or fewer amino acid residues than such amino acid residues. A typical signal peptide consists of three regions, that is, a N-terminal region, a central hydrophobic region, and a more polar C-terminal region. The central hydrophobic region comprises 4 to 12 hydrophobic residues that cause the signal sequence to be immobilized during migration of an immature polypeptide through the membrane lipid bilayer.
After initiation, signal sequences are cleaved in the lumen of ER by cellular enzymes, commonly known as signal peptidases. Here, the signal sequence may be a secretory signal sequence of tPa (tissue plasminogen activator), HSV gDs (signal sequence of Herpes simplex virus glycoprotein D), or a growth hormone. Preferably, a secretory signal sequence used in higher eukaryotic cells including mammals and the like may be used. In addition, as the signal sequence, a wild type signal sequence may be used, or a signal sequence that has been substituted with a codon having high expression frequency in a host cell may be used.
Vector Loaded with Polynucleotide
In another aspect of the present invention, there is provided a vector comprising the polynucleotide. The vector may comprise a polynucleotide encoding a polypeptide of the structural formula (I), (II), (III), and/or (IV). In addition, the vector may comprise a polynucleotide encoding a polypeptide of the structural formula (I′), (II′), (III), and/or (IV).
The vector may be introduced into a host cell to be recombined with and inserted into the genome of the host cell. Alternatively, the vector is understood as nucleic acid means comprising a polynucleotide sequence which is autonomously replicable as an episome. The vectors include linear nucleic acids, plasmids, phagemids, cosmids, RNA vectors, viral vectors, and analogs thereof. Examples of the viral vector include, but are not limited to, retroviruses, adenoviruses, and adeno-associated viruses.
Specifically, the vector may include plasmid DNA, phage DNA, and the like; and commercially developed plasmids (pUC18, pBAD, pIDTSAMRT-AMP, and the like), E. coli-derived plasmids (pYG601BR322, pBR325, pUC118, pUC119, and the like), Bacillus subtilis-derived plasmids (pUB110, pTP5, and the like), yeast-derived plasmids (YEp13, YEp24, YCp50, and the like), phage DNA (Charon4A, Charon21A, EMBL3, EMBL4, λgt10, λgt11, λZAP, and the like), animal viral vectors (retroviruses, adenoviruses, vaccinia viruses, and the like), insect viral vectors (baculoviruses and the like). Since the vector exhibits different expression levels and modification of a protein depending on a host cell, it is preferred to select and use a host cell which is most suitable for the purpose.
As used herein, the term “gene expression” or “expression” of a target protein is understood to mean transcription of DNA sequences, translation of mRNA transcripts, and secretion of fusion protein products or fragments thereof. A useful expression vector may be RcCMV (Invitrogen, Carlsbad) or a variant thereof. The expression vector may comprise human cytomegalovirus (CMV) promoter for promoting continuous transcription of a target gene in mammalian cells, and a bovine growth hormone polyadenylation signal sequence for increasing the stability level of RNA after transcription.
In another aspect of the present invention, there is provided a transformed cell expressing. Specifically, the transformed cell may be one into which the vector has been introduced.
Host cells for the transformed cell may include, but are not limited to, prokaryotic cells, eukaryotic cells, and cells of mammalian, plant, insect, fungal, or cellular origin. As an example of the prokaryotic cells, E. coli may be used. In addition, as an example of the eukaryotic cells, yeast may be used. In addition, for the mammalian cells, CHO cells, F2N cells, CSO cells, BHK cells, Bowes melanoma cells, HeLa cells, 911 cells, AT1080 cells, A549 cells, HEK 293 cells, HEK293T cells, or the like may be used. However, the mammalian cells are not limited thereto, and any cells which are known to those of ordinary skill in the art to be usable as mammalian host cells may be used.
In addition, for the introduction of an expression vector into the host cell, CaCl2) precipitation, Hanahan method whose efficiency has been increased efficiency by using a reducing agent such as dimethyl sulfoxide (DMSO) in CaCl2) precipitation, electroporation, calcium phosphate precipitation, protoplast fusion, agitation using silicon carbide fiber, Agrobacteria-mediated transformation, transformation using PEG, dextran sulfate-, Lipofectamine-, and dry/inhibition-mediated transformation, and the like may be used.
As described above, for optimization of properties of a fusion protein as a therapeutic agent or for any other purpose, glycosylation pattern of the fusion protein (for example, sialic acids, fucosylations, glycosylations) may be adjusted by manipulating, through methods known to those of ordinary skill in the art, glycosylation-related genes possessed by host cells.
In another aspect of the present invention, there is provided a method for producing a fusion protein comprising an antigen-binding site, a first Fc domain or a variant thereof, and a second Fc domain or a variant thereof, the method comprising the steps of: i) culturing the transformed cells; and ii) collecting the produced fusion proteins.
The step of culturing the transformed cells may be carried out using methods well known in the art. Specifically, the culture may be carried out in a batch process, or carried out continuously in a fed batch or repeated fed batch process.
In another aspect of the present invention, there is provided a pharmaceutical composition comprising the fusion protein as an active ingredient.
The pharmaceutical composition may be used for the prevention or treatment of cancer, such as any one cancer selected from the group consisting of gastric cancer, liver cancer, lung cancer, large intestine cancer, breast cancer, prostate cancer, gallbladder cancer, bladder cancer, kidney cancer, esophageal cancer, skin cancer, rectal cancer, osteosarcoma, multiple myeloma, glioma, ovarian cancer, pancreatic cancer, cervical cancer, endometrial cancer, thyroid cancer, laryngeal cancer, testicular cancer, mesothelioma, acute myeloid leukemia, chronic myeloid leukemia, acute lymphoblastic leukemia, chronic lymphoblastic leukemia, brain tumor, neuroblastoma, retinoblastoma, head and neck cancer, salivary gland cancer, and lymphoma.
A preferred dosage of the pharmaceutical composition varies depending on the patient's condition and body weight, severity of disease, form of drug, route and duration of administration and may be appropriately selected by those of ordinary skill in the art. In the pharmaceutical composition for treating or preventing tumor of the present invention, the active ingredient may be contained in any amount (effective amount) depending on application, dosage form, blending purpose, and the like, as long as the active ingredient may exhibit therapeutic activity against tumor or, in particular, may exhibit a therapeutic effect on cancer. A conventional effective amount thereof will be determined within a range of 0.001% to 20.0% by weight, based on the total weight of the composition. Here, the term “effective amount” refers to an amount of an active ingredient that may induce an effect of improving or treating the condition of a disease, especially an effect of improving or treating the condition of cancer. Such an effective amount may be experimentally determined within the scope of common knowledge of those of ordinary skill in the art.
As used herein, the term “treatment” may be used to mean both therapeutic and prophylactic treatment. Here, prophylaxis may be used to mean that a pathological condition or disease of a subject is alleviated or mitigated. In one embodiment, the term “treatment” includes both application or any form of administration for treating a disease in a mammal, including a human. In addition, the term includes inhibiting or slowing down the progression of a disease; and includes meanings of restoring or repairing impaired or lost function so that a disease is partially or completely alleviated; stimulating inefficient processes; or alleviating a serious disease.
Pharmacokinetic parameters such as bioavailability and underlying parameters such as clearance rate may also affect efficacy. Therefore, “improved efficacy” (for example, improvement in efficacy) may be due to improved pharmacokinetic parameters and improved efficacy, which may be measured by comparing clearance rate in test animals or human subjects, and parameters such as tumor treatment or improvement.
As used herein, the term “therapeutically effective amount” or “pharmaceutically effective amount” refers to an amount of a compound or composition effective to prevent or treat the disease in question, which is sufficient to treat the disease at a reasonable benefit/risk ratio applicable to medical treatment and does not cause adverse effects. A level of the effective amount may be determined depending on factors including the patient's health condition, type and severity of disease, activity of drug, the patient's sensitivity to drug, mode of administration, time of administration, route of administration and excretion rate, duration of treatment, combined or simultaneously used drugs, and other factors well known in the medical field. In one embodiment, the therapeutically effective amount means an amount of drug effective to treat cancer.
Here, the pharmaceutical composition may further comprise a pharmaceutically acceptable carrier. The pharmaceutically acceptable carrier may be any carrier as long as the carrier is a non-toxic substance suitable for delivery to a patient. Distilled water, alcohol, fat, wax, and inert solid may be contained as the carrier. A pharmaceutically acceptable adjuvant (buffer, dispersant) may also be contained in the pharmaceutical composition.
Specifically, by including a pharmaceutically acceptable carrier in addition to the active ingredient, the pharmaceutical composition may be prepared into a parenteral formulation depending on its route of administration using conventional methods known in the art. Here, the term “pharmaceutically acceptable” means that the carrier does not have more toxicity than the subject to be applied (prescribed) may adapt while not inhibiting activity of the active ingredient.
When the pharmaceutical composition is prepared into a parenteral formulation, it may be made into preparations in the form of injections, transdermal patches, nasal inhalants, or suppositories with suitable carriers according to methods known in the art. In a case of being made into injections, sterile water, ethanol, polyol such as glycerol or propylene glycol, or a mixture thereof may be used as a suitable carrier; and an isotonic solution, such as Ringer's solution, phosphate buffered saline (PBS) containing triethanol amine or sterile water for injection, and 5% dextrose, or the like may preferably be used. Formulation of pharmaceutical compositions is known in the art, and reference may specifically be made to Remington's Pharmaceutical Sciences (19th ed., 1995) and the like. This document is considered part of the present specification.
A preferred dosage of the pharmaceutical composition may range from 0.01 μg/kg to 10 g/kg, or 0.01 mg/kg to 1 g/kg, per day, depending on the patient's condition, body weight, sex, age, severity of the patient, and route of administration. The dosage may be administered once a day or may be divided into several times a day. Such a dosage should not be construed as limiting the scope of the present invention in any aspect.
Subjects to which the pharmaceutical composition may be applied (prescribed) are mammals including dogs, cats, humans, etc., with humans being particularly preferred. In addition to the active ingredient, the pharmaceutical composition of the present invention may further comprise any compound or natural extract, which is known to have a therapeutic effect on tumor.
In another aspect of the present invention, there is provided a method for treating or preventing cancer, comprising administering a fusion protein comprising an antigen-binding site, a first Fc domain or a variant thereof, and a second Fc domain or a variant thereof administering to a subject.
In another aspect of the present invention, there is provided a use of a fusion protein comprising an antigen-binding site, a first Fc domain or a variant thereof, and a second Fc domain or a variant thereof for the treatment of cancer.
Here, the subject may be an individual suffering from cancer. In addition, the subject may be a mammal, preferably a human.
Route of administration, dosage, and frequency of administration of the fusion protein may vary depending on the patient's condition and the presence or absence of side effects, and thus the fusion protein may be administered to a subject in various ways and amounts. The optimal administration method, dosage, and frequency of administration may be selected in an appropriate range by those of ordinary skill in the art. In addition, the fusion protein may be administered in combination with other drugs or physiologically active substances whose therapeutic effect is known with respect to a disease to be treated, or may be formulated in the form of combination preparations with other drugs.
Hereinafter, the present invention will be described in more detail by way of the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited only to these examples.
Naturally occurring human immunoglobulin G (IgG) consists of two fragment antigen-binding (Fab) regions and one fragment crystallizable (Fc) region (
The object of the present invention is to improve effector function by increasing the amount of Fc region present per antigen while having a molecular weight similar to that of an antibody and having a homogeneous composition. Therefore, we designed a novel antibody format with two Fc regions that has a molecular weight similar to that of a natural human IgG antibody (approximately 150 kDa) (
In order to implement the novel antibody format mentioned above, trastuzumab was used as a template (
Fab in which glutamine (Q) at number 105 of the heavy chain and alanine (A) at number 43 of the light chain are substituted with cysteines, Fab in which phenylalanine (F) at number 122 of the heavy chain and serine (S) at number 121 of the light chain are substituted with cysteines, and Fab in which glycine (G) at number 44 of the heavy chain and glutamine (Q) at number 100 of the light chain are substituted with cysteines were designed, and they were referred to as Mutant 1, Mutant 2, and Mutant 3, respectively (
The notation of the positions in amino acids constituting an antibody follows the Kabat numbering system. In order to minimize unwanted Fc-related byproducts, knob-into-hole mutation technology (Merchant et al., Nat. Biotechnol. 1998) was applied to the Fc domain (SEQ ID NO: 3) of human immunoglobulin G1 (IgG1) to design polypeptides of Fc with knob mutation (S354C and T366W; SEQ ID NO: 4) and Fc with hole mutation (Y349C, T366S, L368A, and Y407V; SEQ ID NO: 5). In order to provide additional flexibility between the CL domain and hinge region, a (G4S)3 linker was introduced (SEQ ID NO: 6;
M1 consists of Fc-Hole (SEQ ID NO: 7), TraH-Q105C-Knob (SEQ ID NO: 10), and TraL-A43C-Knob (SEQ ID NO: 11), M2 consists of Fc-Hole (SEQ ID NO: 7), TraH-F122C-Knob (SEQ ID NO: 12), and TraL-S121C-Knob (SEQ ID NO: 13), and M3 consists of Fc-Hole (SEQ ID NO: 7), TraH-G44C-Knob (SEQ ID NO: 14), and TraL-Q100C-Knob (SEQ ID NO: 15). All of M1, M2, and M3 were expressed in the EXPICHO-S™ (Gibco, A29127) cell line. They were purified using an AKTA pure 25 (Cytiva) or AKTA avant 150 (Cytiva) protein isolation and purification system equipped with a CAPTURESELECT™ CH1-XL Pre-packed Column (Thermo Scientific, 494346205) purification column, and the purified product was further subjected to affinity chromatography using KappaSelect resin (Cytiva, 17545801), and the sample was concentrated using an Amicon Ultra-15 Centrifugal Filter Unit (Merck millipore). For the final purified product, the absorbance of the sample at 280 nm was measured using a NanoDrop One trace spectrophotometer (Thermo Fisher Scientific), and the concentration was quantified based on the sample's intrinsic extinction coefficient and molecular weight.
The purified product was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography (SEC) (
For size exclusion chromatography analysis, an ALLIANCE® HPLC-e2695 Separations Module (Waters, 2695) equipped with an Agilent Bio SEC-3 HPLC column (Agilent, 5190-2511) was used. The analysis showed that the main product was identified at a retention time of 8.6 to 8.8 minutes (
Based on the M3 structure, the impact of the linker that connects the CL domain with the hinge region on the structural integrity of the antibody were analyzed. M3 has a 15-mer polypeptide linker consisting of (G4S)3, and V1 (SEQ ID NO: 7, 14, and 16) and V2 (SEQ ID NO: 7, 14, and 17) have polypeptide linkers of (G4S)2 and G4S, respectively, and V3 (SEQ ID NO: 7, 14, and 18) directly linked the CL domain and the hinge region without a linker (
Based on these results, it was found that the Fab-(Fc)2 structure was stably formed when the VH 44 and VL 100 positions of Fab were substituted with respective cysteines.
Table 9 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of H01. Table 10 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of H01.
Table 11 below shows the H01 heavy chain and light chain CDR sequences.
M3 is characterized by a (trastuzumab Fab)-(Fc)2 structure with mutations of VH G44C and VL Q100C, hereinafter referred to as H01. Similarly, based on the VH and VL regions of pertuzumab (SEQ ID NOs: 27 and 28), the (pertuzumab Fab)-(Fc)2 structure with the mutations VH G44C and VL Q100C is hereinafter referred to as P01. For P01, expression vectors containing the sequences corresponding to Fc-Hole (SEQ ID NO: 7), PerH-G44C-Knob (SEQ ID NO: 29), and PerL-Q100C-Knob (SEQ ID NO: 30) were co-transfected into EXPICHO-S™ (Gibco, A29127), and purification and analysis were performed in the same manner as described in Example 1.
Table 14 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of P01. Table 15 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of P01.
Table 16 below shows CDR sequences in heavy and light chains of the P01.
Papain recognizes specific sequences in the hinge region and induces antibody digestion. In the case of the Fab-(Fc)2 structure, when papain digestion is performed, it is cleaved into a Fab portion of approximately 49.3 kDa and two Fc domains of approximately 50.4 kDa (
To verify this, papain digestion of H01 and P01 was performed. Papain (Sigma, P3125) was used by diluting it to 0.1 mg/mL in digestion buffer (20 mM EDTA+10 mM Cys-HCl in PBS pH 7.4). 200 μg of H01 and P01 were digested at 37° C. for 2 hours, and then SDS-PAGE was performed. As a result of SDS-PAGE performed under non-reducing conditions, abnormal (Fc)2 at about 100 kDa was not identified (
In H01, four Fc monomers are assembled into two Fc dimers due to knob-into-hole mutations, resulting in a structure as shown in
Expression vectors containing sequences corresponding to wtFc (SEQ ID NO: 39), TraH-G44C-wtFc (SEQ ID NO: 40), and TraL-Q100C-wtFc (SEQ ID NO: 41) were co-transfected into EXPICHO-S™ (Gibco, A29127), and purification and analysis were performed in the same manner as described in Example 1. SDS-PAGE analysis under non-reducing conditions (NR) identified a small amount of H01 wt at about 150 kDa, and most of H01 wt were expressed as abnormally structured byproducts (
Table 18 below shows the nucleotide sequences encoding wtFc, TraH-G44C-wtFc, and TraL-Q100C-wtFc of H011 wt.
The schematic diagram of Fv-(Fc)2, in which two Fc domains are fused in parallel to an antibody Fv fragment, is shown in
Table 20 shows the polypeptide sequences constituting H01Fv1 to H01Fv7.
Table 21 shows the nucleotide sequences encoding polypeptides constituting H01Fv1 to H01Fv7.
When expression vectors containing the sequences corresponding to Fc-Hole-F (SEQ ID NO: 789), H01Fv1-HC (SEQ ID NO: 790), and H01Fv1-LC (SEQ ID NO: 791) were co-transfect into EXPICHO-S™ (Gibco, A29127), H01Fv1 was formed (
Analysis of thermal stability was performed using the PROTEIN THERMAL SHIFT™ Dye Kit (Applied biosystems, 4461146) according to the manufacturer's manual. Briefly, 5 μL of reaction buffer and 2.5 μL of dye included in the kit were mixed with 5 μg of trastuzumab, pertuzumab, H01, or P01, and the final volume was adjusted to 20 μL using PBS.
The mixture was incubated at 20° C. for 30 seconds in a C1000 thermal cycler (Bio-Rad, 1841000) equipped with a CFX96 optical reaction module (Bio-Rad, 1845096), and the fluorescence intensity of the plate was measured while increasing the temperature from 20° C. to 95° C. at 1° C./min, and the reaction was stopped after incubation at 95° C. for 30 seconds.
After the reaction, the median value of relative fluorescence unit (RFU) values was taken, and analysis of melting temperature (Tm) was performed. The Tm1 values were found to be 68, 68, 66, and 66° C. and the Tm2 values were found to be 81, 79, 83, and 83° C. for trastuzumab, pertuzumab, H01, and P01, respectively, indicating that H01 and P01 have Tm values similar to those of commercialized therapeutic antibodies (
In order to identify whether H01 and P01 bind to different epitopes or compete for binding, Octet Red96e (Sartorius), a bio-layer interferometry (BLI), was used.
The human HER2 recombinant protein (R&D systems, 1129-ER) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). 100 nM human IgG1 (Bio X cell, BE0297) or 100 nM H01 or 100 nM trastuzumab was first bound to each biosensor loaded with HER2 antigen, followed by 100 nM human IgG1, 100 nM P01, or 100 nM pertuzumab to determine whether they bind competitively (
The first and second analytes were sequentially bound with binding time and dissociation time of 900 seconds. When the human IgG1 antibody was sequentially bound, it did not bind to HER2 (
When H01 and P01 are treated in combination, a total of 16 Fc domains bind to four HER2 antigens present on the surface of cancer cells (
NCI-N87, BT474, SK-OV-3, SNU1, and SNU5 cancer cell lines used to quantify Fc loads of the antibodies on the surface of HER2-expressing cells were cultured in RPMI-1640+10% FBS medium. The cancer cell lines were treated with 50 nM human IgG1 (Bio X cell, BE0297), 50 nM trastuzumab (TRA), or 50 nM trastuzumab+50 nM pertuzumab (TRA+PER), 50 nM H01, 50 nM H01+50 nM P01 antibody at 4° C. for 30 minutes in a 96-well plate. Thereafter, they were treated with the Alexa 488 fluorescence-conjugated anti-human IgG Fcγ Fab antibody (Jackson ImmunoResearch, 109-547-008), and the antibody Fc bound to the cells was quantified using a flow cytometer (BD biosciences, FACSverse) (
In order to determine the saturation concentration of antibodies binding to the cell surface, each test antibody was allowed to bind to a final concentration of 20, 50, and 100 nM, and the subsequent sampling process was carried out in the same manner as the above experimental conditions (
The S239D and I332E mutations in the antibody Fc domain improve the affinity of the antibody for Fcγ receptors, which leads to improved effector function (Greg A. Lazar et al., PNAS, 2006). H01DE4 and P01DE4 were designed by introducing the S239D and I332E mutations in the H01 and P01 Fc domains (
Binding characteristics were analyzed at 25° C. using Octet Red96e (Sartorius), a bio-layer interferometry (BLI). The buffer used for analysis was 10× Kinetics Buffer (Sartorius, 18-1042) diluted in PBS pH 7.4 (Gibco, 10010), and analysis plate was agitated at 1,000 rpm. The human HER2 recombinant protein (R&D systems, 1129-ER) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). To measure the binding rate constant (Ka), 1 to 32 nM of H01, H01DE4, P01, and P01DE4 were allowed to bind to loaded antigen for 300 seconds and then the dissociation rate constant (Kd) was determined after 600 seconds of dissociation in Kinetics Buffer. Ka and Kd values were measured through a 1:1 binding model in Octet analysis software (Sartorius), and the equilibrium dissociation constant (KD) value was determined (
The binding constants of each antibody to Fcγ receptors at 25° C. were analyzed using Octet Red96e (Sartorius). Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120) was used, and human FcγRI (R&D systems, 1257-FC) or human FcγIIA (R&D systems, 1330-CD) or human FcγRIIIA (176V isoform, R&D systems, 4325-FC) containing a His tag were loaded onto the biosensor.
The association rate constants (Ka) and the dissociation rate constants (Kd) of H01, P01, H01DE4, P01DE4, human IgG1 (Bio X cell, BE0297), trastuzumab, pertuzumab, and margetuximab to the biosensor loaded with an antigen was determined. Ka and Kd values were calculated through a 1:1 binding model in Octet analysis software (Sartorius), and the equilibrium dissociation constant (KD) value was determined (
H01, P01 trastuzumab, and pertuzumab were administered at 10 mg/kg to 7-week-old male Sprague-Dawley rats (ORIENT BIO INC.) via the intravenous (i.v.) route. Blood samples were collected in 5 minutes, 15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, 8 hours, 1 day, 2 days, 3 days, 7 days, 10 days, 14 days, 21 days, 28 days, 35 days, and 42 days after administration. Thereafter, only the serum was separated from the blood for analysis. The antibody concentration in serum was measured by ELISA.
Briefly, a 96-well ELISA plate (Corning, 3590) was coated with human HER2 recombinant protein (R&D systems, 1129-ER) and stored overnight at 4° C., and the sera obtained at each time were appropriately diluted, and allowed to bind to the coated human HER2. Peroxidase-conjugated anti-human Fab goat antibody (Invitrogen, 31482) was used to detect H01, P01 trastuzumab, and pertuzumab.
Standard samples of H01, P01, trastuzumab, and pertuzumab were prepared, and the concentrations of the analytes at each time point were quantified based on a standard curve created from naive rat serum containing different concentrations of the antibody standards. The half-lives of intravenously administered H01, P01, trastuzumab, and pertuzumab were determined to be approximately 11.8 days, 14.2 days, 7.3 days, and 11.6 days, respectively (
In order to construct an antibody that recognizes two epitopes of HER2 protein, a biparatopic antibody HP51 was designed by connecting the V domains of trastuzumab and pertuzumab via a linker (
For HP51, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), TN-S-PH-Knob (SEQ ID NO: 51), and TL-S-PL-Knob (SEQ ID NO: 59) were co-transfected into EXPICHO-S™ (Gibco, A29127) (Tables 31, 32, 33, and 34), and purification and analysis were performed in the same manner as described in Example 1. Expression, purification and analysis were performed for HP502 to HP516 in the same manner as mentioned above, and the composition of the expression vector is shown in detail
Purity was analyzed by size exclusion chromatography in the same manner as described in Example 1 (
The binding constants of HP501, HP502, HP503, HP504, HP505, HP506, HP507, HP508, HP509, HP510, HP511, HP512, HP513, HP514, HP515, and HP516 to D2 region and D4 region in HER2 protein were determined using the Octet Red96e (Sartorius). In order to analyze the binding constants of the sixteen antibodies to the D2 region, the human HER2 recombinant protein (R&D systems, 1129-ER) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120) and then saturated with 100 nM trastuzumab which targets the D4 region. Thereafter, the sixteen antibodies were added in a binding reaction (300 seconds) and a dissociation reaction (600 seconds) at a concentration of 100 nM, and their affinities for the D2 region were calculated (Table 36). In order to analyze the binding constants of the sixteen antibodies to the D4 region, the human HER2 recombinant protein (R&D systems, 1129-ER) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120), and then saturated with 100 nM pertuzumab which targets the D2 region. Thereafter, the sixteen antibodies were added in a binding reaction (300 seconds) and a dissociation reaction (600 seconds) at a concentration of 100 nM, and their affinities for the D4 region were calculated (Table 36). The binding constants of HP507, HP511, and HP515 to D2 region were 2.285, 3.267, and 2.012 nM, respectively, showing excellent binding affinities to the D2 region compared to other clones (Table 36). HP503 has a binding constant of 8.098 nM to the D2 region and shows a relatively low binding ability to the D2 region compared to HP507, HP511, and HP515. However, it was found that when measuring the binding constant to the D4 region, the binding constants of HP503, HP507, HP511, and HP515 were 0.181, 0.228, 0.162, and 0.227 nM, respectively, demonstrating strong binding affinity Table 36).
The binding constants of HP503, HP507, HP511, and P515 to the HER2 extracellular domain (ECD) were measured using Octet Red96e (Sartorius). The human HER2 recombinant protein (R&D systems, 1129-ER) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). HP503 or P57 or P5 or) P515 at a concentration of 0.25, 0.5, 1, 2, 4, or 8 nM were added in a binding reaction (600 seconds) and a dissociation reaction (1,800 seconds) in the sensor loaded with the HER2 protein, and the binding constants were calculated (
The measured binding constants of HP503, HP507, HP511, and BP515 to Fcγ receptors were analyzed using Octet Red96e (Sartorius) in the same manner as described in Example 10 (
The binding constants of HP503, HP507, BP511, and BP515 to the neonatal Fc receptor (FcRn) were measured using Octet Red96e (Sartorius). HP503, HP507, BP511, HP515, human IgG1 (Bio X cell, BE0297), trastuzumab, pertuzumab, and margetuximab were loaded onto the anti-human Fab-CH1 2nd generation (FAB2G) biosensor (Sartorius, 18-5126), and a binding and a dissociation time were set to be 120 seconds, respectively (
For the analysis of complement-dependent cytotoxicity, BT474 (HER2 3+; high) breast cancer cell line and NCI-N87 (HER2 3+; high) gastric cancer cell line were used. The cells were diluted in cell culture medium and dispensed in a 96-well plate at 10,000 cells per well. The cells, antibodies, and human serum (Sigma, H4522) were each reacted at a volume ratio of 1:1:1.
In order to identify a dose-response relationship, human IgG1, trastuzumab (TRA), trastuzumab+pertuzumab (TRA+PER), H01, and H01+P01 were serially diluted by a factor of two six times from initial concentration of 1200 nM, and the reaction was carried out from 400 nM (another three-fold dilution when dispensed). The human serum was diluted and dispensed in the culture medium to a final concentration of 25%, and the mixture of the cells, antibodies, and human serum was incubated for 5 hours in a humidified incubator at 37° C. and 5% (v/v) C02 conditions.
Cell Titer Glo-Reagent (Promega, G9243) previously dissolved at 4° C. was dispensed into each well in an equal volume of the mixed culture medium, and then the cell lysis was induced using a plate shaker (Allsheng, MX100-4A) with agitation at 500 rpm for 2 minutes. In order to stabilize the luminescence signal, the mixture was incubated at room temperature for 10 minutes and then analyzed using a plate reader equipment (Envision; PerkinElmer, 2105-0010) (
Human IgG1, trastuzumab (TRA), trastuzumab+pertuzumab (TRA+PER), and H01 did not induce CDC responses in BT474 and NCI-N87 cell lines (
NCI-N87 (HER2 3+; high), MDA-MB-453(HER2 2+; Mid), SNU-601 (HER2 1+; low), and SNU-5 (HER2 1+; low) cancer cell lines were used for antibody-dependent cell-mediated cytotoxicity analysis (
After treatment, the cells were incubated for 18 hours in a humidified incubator at 37° C. and 5% (v/v) C02 conditions, and then cytotoxicity was measured using a cytotoxicity detection kit (LDH) (Roche, 11644793001) (
Cytotoxicity (%)=[(Test release-spontaneous release)/(Maximum release-spontaneous release)]×100 <Equation 2>
H01 showed excellent cytotoxicity at a low concentration compared to trastuzumab in NCI-N87 (HER2 3+; high) and MDA-MB-453 (HER2 2+; Mid) cancer cell lines (
Efficacy in the SNU-5 (HER2 1+; low) gastric cancer cell line-derived xenograft model was evaluated using 6-week-old female SCID mice (C.B-17/NcrKoat-Prkdcscid, Koatech) (
In addition, efficacy in the SNU-5 (HER2 1+; low) gastric cancer cell line-derived xenograft model was evaluated using 6-week-old female BALB/c-nu mice (ORIENT BIO INC.) (
Efficacy in the SNU-601 (HER2 1+; low) gastric cancer cell line-derived xenograft model was evaluated using 6-week-old female SCID mice (C.B-17/NcrKoat-Prkdcscid, Koatech). The SNU-5 cancer cell line was diluted in PBS at 1×107 cells/100 μL and mixed with MATRIGEL® Growth Factor Reduced (GFR) Basement Membrane Matrix (Corning, 354230) at a ratio of 1:1, and 100 μL of the mixture was transplanted subcutaneously into the right flank, and tumor growth was observed. Mice were regrouped so that the average tumor volume was about 142 mm3, and PBS (vehicle), 5 mg/kg H01, 5 mg/kg trastuzumab, and 5 mg/kg trastuzumab+5 mg/kg pertuzumab were administered intraperitoneally (I.P.) twice a week for a total of 6 weeks (
Efficacy in the NCI-N87 (HER2 3+; high) gastric cancer cell line-derived xenograft model was evaluated using 6-week-old female SCID mice (C.B-17/NcrKoat-Prkdcscid, Koatech). The NCI-N87 cancer cell line was diluted in PBS at 5×106 cells/100 μL and mixed with MATRIGEL® Growth Factor Reduced (GFR) Basement Membrane Matrix (Corning, 354230) at a ratio of 1:1, and 100 μL of the mixture was transplanted subcutaneously into the right flank, and tumor growth was observed. Mice were regrouped so that the average tumor volume was about 146 mm3, and PBS (vehicle), 0.2 mg/kg H01, 5 mg/kg H01, 0.2 mg/kg trastuzumab, and 5 mg/kg trastuzumab were administered intraperitoneally (I.P.) twice a week for a total of 6 weeks (
The nucleotide (SEQ ID NO: 566, Table 40) encoding the human HER2 protein (SEQ ID NO: 567, Table 40) was cloned into a protein expression vector (ORIGENE, PS100020) containing a neomycin-resistance gene to construct the human HER2 expression vector pCMV6-AC-hHER2 (
The mouse large intestine-derived CT26 cancer cells were transfected with the pCMV6-AC-hHER2 human HER2 expression vector using the lipofectamine 2000 transfection reagent (Invitrogen, 11668-019). Only cells transfected with the pCMV6-AC-hHER2 human HER2 expression vector were selected by incubating the transfected cells in culture medium containing 1 mg/mL G418 (Invivogen, ant-gn-5) for 14 days. The top 3% clones in terms of HER2 expression was sorted into a 96-well plate (ThermoFisher, 167008) with 1 cell per well using SH800S Cell Sorter (SONY). Selection was performed by incubation in G418-containing medium for 21 days, and a total of 8 CT26 mouse large intestine cancer cell line clones expressing human HER2 were obtained, and human HER2 expression in these cells was monitored by flow cytometer (BD Biosciences, FACSverse) analysis after staining with the anti-human HER2-BV421 (BD, 744811) (
Alter subculturing six times tor 20 days in a (G418-free environment, the cells were stained with the anti-human HER2-BV421 (BD, 744811), and the level of human HER2 expression was measured. It was shown that the level of human HER2 expression was not reduced in cells grown without G418 compared to cells grown with G418 (
To compare the cell surface Fc loads among the parental CT26, CT26-HER2 cell line (Clone #2-60) and human cancer cell lines (SNU5, SNU601, and NCI-N87), each cell was allowed to bind to 100 nM human IgG1 (Bio X cell, BE0297), 100 nM trastuzumab (TRA), and 100 nM H01 antibody at 4° C. for 30 minutes in a 96-well v-bottom plate (Corning, 3363). Thereafter, they were treated with the Alexa 488 fluorescence-conjugated anti-human IgG Fcγ Fab antibody (Jackson ImmunoResearch, 109-547-008), and the Fc loads on the cells were quantified using a flow cytometer (
Efficacy in the CT26-HER2 (Clone #2-60) syngeneic mouse model was evaluated using 6-week-old female Balb/c mice (ORIENT BIO INC.). PBS (vehicle), 5 mg/kg trastuzumab, and 5 mg/kg H01 were administered intraperitoneally (I.P.) twice a week for a total of 2 weeks (
The variant light chain and heavy chain polypeptide sequences of the antibodies that specifically recognize the glypican-3 (GPC-3) protein are shown in Table 44. For GPM01, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), GPM01 HC (SEQ ID NO: 67), and GPM01 LC (SEQ ID NO: 68) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 46 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting GPC-3. Table 47 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting GPC-3.
Table 48 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting GPC-3.
The GPC-3 protein binding constants of GPM01, GPM02, GPM04, GPB01, GPB03, GPB04, and GPB06 were determined using the Octet Red96e (Sartorius). In order to analyze the binding constants of the seven antibodies, the human GPC-3 recombinant protein (Sino Biologicals, 10088-H08H) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). Then the seven antibodies were added in a binding reaction (300 seconds) and a dissociation reaction (1,200 seconds) at various concentrations, and their affinities for GPC-3 were calculated (
HepG2 liver cancer cell line was used to quantify the Fc loads on the surface of GPC-3 expressing cells. 100 nM human IgG1, GPM02, GPB01, GPB03, and GC33 were allowed to bind to the HepG2 cell line at 4° C. for 30 minutes, and the Fc loads were quantified using the Alexa 488 fluorescence-conjugated anti-human IgG Fcγ Fab antibody (Jackson ImmunoResearch, 109-547-008) (
The variant light chain and heavy chain polypeptide sequences of the antibodies that specifically bind to the EPH receptor A2 (EphA2) protein are shown in Table 46. For EPB01, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), EPB01 HC (SEQ ID NO: 111), and EPB01 LC (SEQ ID NO: 112) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 52 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting EphA2. Table 53 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting EphA2.
Table 54 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting EphA2.
The EphA2 protein binding constants of EPB01, EPB02, EPB03, EPB04, EPB05, EPB06, EPB07, EPB08, EPB09, EPB10, EPB11, and EPB12 were determined using Octet Red96e (Sartorius). In order to analyze the binding constants of the twelve biparatopic antibodies, the human EphA2 recombinant protein (Sino Biologicals, 13926-H08H) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120), and then the twelve antibodies were added in a binding reaction (300 seconds) and a dissociation reaction (1,200 seconds) at various concentrations. Based on the above, the affinity for EphA2 was calculated (Table 55). Table 55 below illustrates a result obtained by analyzing the binding constants of the engineered antibodies targeting EphA2.
PC-3 prostate cancer cell line was used to analyze the ability of antibodies to inhibit EphA2 signaling. PC-3 cancer cell lysate treated with each antibody at a concentration of 50 nM for 30 minutes was analyzed by western blot. The 1C1 humanized antibody that targets human EphA2 was used as a positive control and was prepared based on the sequence published in the literature (Kinch et al., US 20090304721 A1). Akt Rabbit mAb (Cell Signaling Technology, 9272), Phospho-Akt (Ser473) (D9E) XP® Rabbit mAb (Cell Signaling Technology, 4060), and β-Actin (13E5) Rabbit mAb (Cell Signaling Technology, 4970) were used as primary antibodies for analysis, and anti-rabbit IgG, HRP-linked antibody (Cell Signaling Technology, 7074) was used as secondary antibody. In the analysis of AKT signaling pathway inhibition, EPB02, EPB03, and EPB05 showed a similar level of inhibition as the positive control 1C1 (
PC-3 prostate cancer cell line was used to quantify the Fc loads on the surface of EphA2 expressing cells. 100 nM antibodies were allowed to bind to the PC-3 cell line at 4° C. for 30 minutes, and the Fc loads were quantified using the Alexa 488 fluorescence-conjugated anti-human IgG Fcγ Fab antibody (Jackson ImmunoResearch, 109-547-008) (
The variant light chain and heavy chain polypeptide sequences of the antibodies that specifically bind to the MET protein are shown in Table 56. For MEM01, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), MEM01 HC (SEQ ID NO: 568), and MEM01 LC (SEQ ID NO: 569) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 58 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting MET. Table 59 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting MET.
Table 60 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting MET.
The MET protein binding constants of MEM01 and MEM06 were determined using Octet Red96e (Sartorius). In order to analyze the binding constants of the antibodies, the antibodies were loaded onto the anti-human Fab-CH1 2nd generation (FAB2G) biosensor (Sartorius, 18-5125). Then, the human MET recombinant protein (Sino Biologicals, 10692-H08H) were added in a binding reaction (300 seconds) and a dissociation reaction (600 seconds) at various concentrations (
MKN45 and SNU-5 gastric cancer cell lines were used to quantify the Fc loads on the surface of MET expressing cells. The human IgG1 control, onartuzumab (produced in CHO cell line), emibetuzumab, MEM01I, and MEM06 antibodies were allowed to bind to the cell lines at 4° C. for 30 minutes, and the Fc loads were quantified using the Alexa 488 fluorescence-conjugated anti-human IgG Fcγ Fab antibody (Jackson ImmunoResearch, 109-547-008) (
The variant light chain and heavy chain polypeptide sequences of the antibodies that specifically bind to the EGFR protein are shown in Table 62. For EGM01, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), EGM01 HC (SEQ ID NO: 590), and EGF01 LC (SEQ ID NO: 591) were co-transfected into EXPICHOWS™ (Gibco, A29127) (
Table 63 below shows the heavy chain and light chain nucleotide sequences of the engineered antibodies targeting EGFR.
Table 64 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting EGFR. Table 65 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting EGFR.
Table 66 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting EGFR.
The EGFR protein binding constants of EGM01 to EGM05 were determined using the Octet Red96e (Sartorius). In order to analyze the binding constants of the antibodies, the antibodies were loaded onto the anti-human Fab-CH1 2nd generation (FAB2G) biosensor (Sartorius, 18-5125). Then, the human EGFR recombinant proteins (Sino Biologicals, 10692-H08H) were added in a binding reaction (300 seconds) and a dissociation reaction (600 seconds) at various concentrations (
The variant light chain and heavy chain polypeptide sequences of the antibodies that specifically recognize the CD33 protein are shown in Table 68. For GPM01, expression vector consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), 33-1 HC (SEQ ID NO: 636), and 33-1 LC (SEQ ID NO: 637) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 70 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting CD33. Table 71 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting CD33.
Table 72 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting CD33.
The CD33 protein binding constants of 33-1, 33-2, 33-3, 33-4, 33-5, 33-6, and 33-7 were determined using Octet Red96e (Sartorius). In order to analyze the binding constants of the seven antibodies, the human CD33 recombinant protein (Sino Biologicals, 12238-H08H) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). Then, the seven antibodies were added in a binding reaction (600 seconds) and a dissociation reaction (1,200 seconds) at various concentrations, and their affinities for CD33 were calculated (
The light chain and heavy chain variant polypeptide sequences of the antibodies that specifically bind to the CEACAM5 protein are shown in Table 74. For CEA01, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), CEA01 HC (SEQ ID NO: 590), and CEA01 LC (SEQ ID NO: 591) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 75 below shows the heavy chain and light chain nucleotide sequences of the engineered antibodies targeting CEACAM5.
Table 76 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting CEACAM5. Table 77 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting CEACAM5.
Table 78 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting CEACAM5.
In order to analyze the binding constants, the human CEACAM5 recombinant protein (Sino Biologicals, 11077-H08H) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). Then, the antibodies were added in a binding reaction (600 seconds) and a dissociation reaction (1,200 seconds) at various concentrations, and their affinities for human CEACAM5 were calculated (
The variant light chain and heavy chain polypeptide sequences of the antibody T01 that specifically binds to the TROP2 protein are shown in Table 80. For T01I, expression vectors consisting of the sequences corresponding to Fc-Hole (SEQ ID NO: 7), T01 HC (SEQ ID NO: 753), and T01 LC (SEQ ID NO: 754) were co-transfected into EXPICHO-S™ (Gibco, A29127) (
Table 81 below shows the heavy chain and light chain nucleotide sequences of the engineered antibodies targeting TROP2, mesothelin, or LIV-1.
Table 82 below shows the polypeptide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting TROP2, mesothelin, or LIV-1. Table 83 below shows the nucleotide sequences of the heavy chain variable region (VH) and light chain variable region (VL) of the engineered antibodies targeting TROP2, mesothelin, or LIV-1.
Table 84 below shows the heavy chain and light chain CDR sequences of the engineered antibodies targeting TROP2, mesothelin, or LIV-1.
In order to analyze the binding constants, the human TROP2 recombinant protein (Sino Biologicals, 10428-H08H), the human mesothelin recombinant protein (Sino Biologicals, 13128-H08H) or the human LIV-1 recombinant protein (Acro biosystems, LV1-H5223) was loaded onto the Anti-Penta-HIS (HIS1K) biosensor (Sartorius, 18-5120). Then, the antibodies were added in a binding reaction and a dissociation reaction at various concentrations, and the affinities of each antibody for the human antigen was calculated (
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0142135 | Oct 2021 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/015981 | 10/22/2022 | WO |
