WO2016003869A1 - Anticorps réagissant avec un épitope situé dans la région n-terminale de muc5ac comprenant un sous-domaine 2 riche en cystéine (cys2) - Google Patents

Anticorps réagissant avec un épitope situé dans la région n-terminale de muc5ac comprenant un sous-domaine 2 riche en cystéine (cys2) Download PDF

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Publication number
WO2016003869A1
WO2016003869A1 PCT/US2015/038252 US2015038252W WO2016003869A1 WO 2016003869 A1 WO2016003869 A1 WO 2016003869A1 US 2015038252 W US2015038252 W US 2015038252W WO 2016003869 A1 WO2016003869 A1 WO 2016003869A1
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Prior art keywords
antibody
seq
muc5ac
antibodies
pancreatic cancer
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PCT/US2015/038252
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English (en)
Inventor
Donglin Liu
Chien-Hsing Chang
David M. Goldenberg
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Immunomedics, Inc.
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Priority claimed from US14/632,480 external-priority patent/US9238084B2/en
Application filed by Immunomedics, Inc. filed Critical Immunomedics, Inc.
Priority to CA2948013A priority Critical patent/CA2948013A1/fr
Priority to EP15815785.9A priority patent/EP3160499A4/fr
Publication of WO2016003869A1 publication Critical patent/WO2016003869A1/fr

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K51/00—Preparations containing radioactive substances for use in therapy or testing in vivo
    • A61K51/02—Preparations containing radioactive substances for use in therapy or testing in vivo characterised by the carrier, i.e. characterised by the agent or material covalently linked or complexing the radioactive nucleus
    • A61K51/04—Organic compounds
    • A61K51/08—Peptides, e.g. proteins, carriers being peptides, polyamino acids, proteins
    • A61K51/10—Antibodies or immunoglobulins; Fragments thereof, the carrier being an antibody, an immunoglobulin or a fragment thereof, e.g. a camelised human single domain antibody or the Fc fragment of an antibody
    • A61K51/1045—Antibodies or immunoglobulins; Fragments thereof, the carrier being an antibody, an immunoglobulin or a fragment thereof, e.g. a camelised human single domain antibody or the Fc fragment of an antibody against animal or human tumor cells or tumor cell determinants
    • A61K51/1057—Antibodies or immunoglobulins; Fragments thereof, the carrier being an antibody, an immunoglobulin or a fragment thereof, e.g. a camelised human single domain antibody or the Fc fragment of an antibody against animal or human tumor cells or tumor cell determinants the tumor cell being from liver or pancreas
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
    • A61K31/7042—Compounds having saccharide radicals and heterocyclic rings
    • A61K31/7052—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides
    • A61K31/706—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom
    • A61K31/7064—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom containing condensed or non-condensed pyrimidines
    • A61K31/7068—Compounds having saccharide radicals and heterocyclic rings having nitrogen as a ring hetero atom, e.g. nucleosides, nucleotides containing six-membered rings with nitrogen as a ring hetero atom containing condensed or non-condensed pyrimidines having oxo groups directly attached to the pyrimidine ring, e.g. cytidine, cytidylic acid
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/70—Carbohydrates; Sugars; Derivatives thereof
    • A61K31/7088—Compounds having three or more nucleosides or nucleotides
    • A61K31/7105—Natural ribonucleic acids, i.e. containing only riboses attached to adenine, guanine, cytosine or uracil and having 3'-5' phosphodiester links
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K45/00—Medicinal preparations containing active ingredients not provided for in groups A61K31/00 - A61K41/00
    • A61K45/06—Mixtures of active ingredients without chemical characterisation, e.g. antiphlogistics and cardiaca
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6835—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site
    • A61K47/6851—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a determinant of a tumour cell
    • A61K47/6859—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a determinant of a tumour cell the tumour determinant being from liver or pancreas cancer cell
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6891—Pre-targeting systems involving an antibody for targeting specific cells
    • A61K47/6897—Pre-targeting systems with two or three steps using antibody conjugates; Ligand-antiligand therapies
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/30—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells
    • C07K16/303—Liver or Pancreas
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/30—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells
    • C07K16/3076—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells against structure-related tumour-associated moieties
    • C07K16/3092—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells against structure-related tumour-associated moieties against tumour-associated mucins
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
    • G01N33/53—Immunoassay; Biospecific binding assay; Materials therefor
    • G01N33/574—Immunoassay; Biospecific binding assay; Materials therefor for cancer
    • G01N33/57407—Specifically defined cancers
    • G01N33/57438—Specifically defined cancers of liver, pancreas or kidney
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K38/00—Medicinal preparations containing peptides
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/70—Immunoglobulins specific features characterized by effect upon binding to a cell or to an antigen
    • C07K2317/72—Increased effector function due to an Fc-modification
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2333/00—Assays involving biological materials from specific organisms or of a specific nature
    • G01N2333/435—Assays involving biological materials from specific organisms or of a specific nature from animals; from humans
    • G01N2333/46—Assays involving biological materials from specific organisms or of a specific nature from animals; from humans from vertebrates
    • G01N2333/47—Assays involving proteins of known structure or function as defined in the subgroups
    • G01N2333/4701—Details
    • G01N2333/4725—Mucins, e.g. human intestinal mucin

Definitions

  • This invention relates to anti-pancreatic cancer antibodies and antigen-binding fragments thereof that bind to MUC5AC mucin in pancreatic cancer.
  • the antibodies or fragments thereof bind to an epitope located within the second to fourth cysteine- rich subdomains of MUC5AC (amino acid residues 1575-2052, Cys2-Cys4). More preferably, the antibodies bind to an epitope located in amino acid residues 1 75-1725 and 1903-2052 (Cys2 and Cys4). Even more preferably, the antibodies bind to an epitope located in amino acid residues 1575-1725 (Cys2+).
  • the antibodies bind to an epitope located in the Cys2 subdomain of MUC5AC.
  • the anti-pancreatic cancer antibody binds to the same epitope as, or competes for binding to MUC5AC with a PAM4 antibody comprising the light chain variable region complementarity-determining region (CDR) sequences CDR1 (SASSSVSSSYLY, SEQ ID NO: l); CDR2 (STSNLAS, SEQ ID NO:2); and CDR3 (HQWNR YPYT, SEQ ID NO:3); and the heavy chain CDR sequences CDRl (SYVLH, SEQ ID NO:4); CDR2 (YI PYNDGTQYNEKFKG, SEQ ID NO:5)and
  • CDR light chain variable region complementarity-determining region
  • the subject antibodies or antibody fragments bind with high selectivity to pancreatic cancer ceils to allow detection and/or diagnosis of pancreatic adenocarcinoma at the earliest stages of the disease.
  • antibody- based assays are capable of detecting about 85% or more of pancreatic adenocarcinomas, with a false positive rate of about 5% or less for healthy controls.
  • the methods and compositions can be used to detect and/or diagnose pancreatic
  • adenocarcinoma by screening serum samples from subjects and preferably can detect 60% or more of stage I pancreatic cancers and 80% or more of stage II cancers by serum sample analysis, in still other embodiments, reactivity with the anti-pancreatic cancer antibody can be used to detect occult pancreatic cancer or neoplastic precursor lesions against a background of pancreatitis or benign pancreatic hyperplasia.
  • the anti-pancreatic cancer antibody is of use for diagnosis, detection and/or treatment of pancreatic cancer.
  • the antibody or fragment thereof may be administered as a naked antibody, as an antibody complex, as an antibody fusion protein, or conjugated to at least one therapeutic agent, such as a radionuclide, an irnmunomodulator, a hormone, a hormone antagonist, an enzyme, an oligonucleotide such as an anti-sense oligonucleotide or a siRNA, an enzyme inhibitor, a photoactive therapeutic agent, a cytotoxic agent such as a drug or toxin, an angiogenesis inhibitor and a pro-apoptotic agent.
  • the antibody is a w Y-hPAM4 antibody and the radiolabeled antibody may be administered in fractionated dosages for treating pancreatic cancer,
  • Biomarkers whether they are biological, chemical, or physical in nature, have pro ven of significant value in providing information leading to the earlier detection and diagnosis of cancer, such as breast (Goldhirsch et al, 2003, Ann Oncol 14:1212-4), colon (Mandel et al., 1993, N Engl J Med 328: 1365-71), and prostate (Jacobsen et al., 1995, JAMA 274: 1445-9), resulting in improved patient outcomes. Unfortunately, this has not been the case for PDAC. Despite considerable attention directed towards discovery of biomarkers for PDAC (Lennon et al., 2014, Cancer Research 74: 1-9), to date no FDA-approved means for early
  • pancreatic cancer In addition to more effective and earlier means of detection, a need also exists for better therapeutic treatments for pancreatic cancer. The outlook for patients with advanced pancreatic adenocarcinoma remains poor (Hidalgo, 2010, N Engl J Med 362:1605-17).
  • the present invention concerns antibodies, antigen-binding antibody fragments and fusion proteins that bind to the MUC5AC pancreatic cancer mucin.
  • the antibodies or fragments thereof bind to an epitope located w ithin the second to fourth cysteine-rich subdomains of MUC5AC (amino acid residues 1575-2052, Cys2-Cys4). More preferably, the antibodies bind to an epitope located in amino acid residues 1575-1725 and 1903-2052 (Cys2 and Cys 4). Even more preferably, the antibodies bind to an epitope located in amino acid residues 1575- 1725 (Cys2+). Most preierably, the antibodies bind to an epitope located in Cys2.
  • the subject antibodies or fragments thereof bind specifically to pancreatic cancer cells, with little or no binding to normal or non-neoplastic pancreatic ceils.
  • the antibodies are capable of binding to the earliest stages of pancreatic cancer, with detection rates of about 50-60% for PanIN-lA, 70-80% for PanlB and 80-90% for PanIN-2. More preferably, the antibodies bind to 80 to 90% or more of human invasive pancreatic adenocarcinoma, intraductal papillary mucinous neoplasia, PanIN-lA, PanIN- lB and PanIN-2 lesions. Most preferably, the antibodies can distinguish between early stage pancreatic cancer and non-malignant conditions such as pancreatitis.
  • Such antibodies are of particular use for early detection of cancer and differential diagnosis between early stage pancreatic cancer and benign pancreatic conditions.
  • such antibodies are of use for in vivo or ex vivo analysis of samples from individuals suspected of having early stage pancreatic or certain other cancers. More preferably, the antibodies are of use for detection and diagnosis of early stage pancreatic cancer by analysis of serum samples.
  • the antibodies, antibody fragments or fusion proteins are capable of binding to synthetic peptide sequences, for example to phage display peptides, such as WTWNITKAYPLP (SEQ ID NO:7) and ACPEWWGTTC (SEQ ID NO:8).
  • synthetic peptides may be linear or cyclic and may or may not compete with antibody binding to the endogenous pancreatic cancer antigen.
  • Amino acids in certain positions of the synthetic peptide sequences may be less critical for antibody binding than others.
  • the residues K, A and L at positions 7, 8 and 1 1 of the peptide sequence may be varied while still retaining antibody binding.
  • SEQ ID NO:8 the threonine residues at positions 8 and 9 of the sequence may be varied, although substitution of the threonine at position 9 may significantly affect antibody binding to the peptide.
  • Binding of the antibodies to a target pancreatic cancer antigen may be inhibited by treatment of the target antigen with reagents such as dithiothreitol (DTT) and/or periodate.
  • DTT dithiothreitol
  • binding of the antibodies to a pancreatic cancer antigen may be dependent upon the presence of disulfide bonds and/or the glycosylation state of the target antigen.
  • the epitope recognized by the subject antibodies is not cross-reactive with other reported mucin-specific antibodies, such as the MAS antibody, the CLH2-2 antibody and/or the 45M1 antibody (see, e.g., Major et al., J Histochem Cvtochem. 35: 139- 48, 1987; Dion et al, Hybridoma 10:595-610, 1991).
  • the subject antibodies or fragments may be naked antibodies or fragments or preferably are conjugated to at least one therapeutic and/or diagnostic agent for delivery of the agent to target tissues.
  • the subject antibodies or fragments may be part of a bispecific antibody with a first binding site for an epitope of MUC5AC as discussed above and a second binding site for a hapten conjugated to a targetable construct.
  • the targetable construct may in turn be attached to at least one therapeutic and/or diagnostic agent, of use in pretargeting techniques,
  • the subject antibody, antibody fragment or fusion protein is a humanized PAM4 antibody or fragment, comprising the light chain variable region CDR sequences CDRI (SASSSVSSSYLY, SEQ ID NO: l ); CDR2 (STSNLAS, SEQ ID NO:2); and CDR3 (HQWNRYPYT, SEQ ID NO:3); and the heavy chain variable region CDR sequences CDRi (SYVLH, SEQ ID NO:4); CDR2 (YINPYNDGTQYNEKFKG, SEQ ID NO:5) and CDR3 (GFGGSYGFAY, SEQ ID NO: 6) and human antibody framework region (FR) and constant region sequences.
  • CDRI SASSSVSSSYLY, SEQ ID NO: l
  • CDR2 STSNLAS, SEQ ID NO:2
  • CDR3 HQWNRYPYT, SEQ ID NO:3
  • CDRi SYVLH, SEQ ID NO:4
  • CDR2 YINPYNDGTQY
  • the FRs of the light and heavy chain variable regions of the humanized PAM4 antibody or fragment thereof comprise at least one amino acid substituted from amino acid residues 5, 27, 30, 38, 48, 66, 67 and 69 of the murine PAM4 heavy chain variable region (SEQ ID NO: 12) and/or at least one amino acid selected from amino acid residues 21, 47, 59, 60, 85, 87 and 100 of the murine PAM4 light chain variable region (SEQ ID NO: 10).
  • the antibody or fragment thereof comprises the hPAM4 V H amino acid sequence of SEQ ID NO: 19 and the hPAM4 V amino acid sequence of SEQ ID NO: 16.
  • the anti-pancreatic cancer antibody may be a chimeric, humanized or human antibody that binds to the same antigenic determinant (epitope) as, or competes for binding to MUC5AC with, a chimeric PAM4 (cPAM4) antibody.
  • cPAM4 chimeric PAM4
  • the cPAM4 antibody is one that comprises the light chain variable region CDR sequences CDRi (SASSSVSSSYLY, SEQ ID NO:l); CDR2 (STSNLAS, SEQ ID NO:2); and CDR3 (HQWNRYPYT, SEQ ID NO:3); and the heavy chain variable region CDR sequences CDRI (SYVLH, SEQ ID NO:4); CDR2 (YINPYNDGTQYNEKFKG, SEQ ID NO:5)and CDR3 (GFGGSYGFAY, SEQ ID NO:6).
  • CDRi SASSSVSSSYLY, SEQ ID NO:l
  • CDR2 STSNLAS, SEQ ID NO:2
  • CDR3 HQWNRYPYT, SEQ ID NO:3
  • CDRI SYVLH, SEQ ID NO:4
  • CDR2 YINPYNDGTQYNEKFKG, SEQ ID NO:5
  • CDR3 GGGSYGFAY, SEQ ID NO:6
  • Antibodies that bind to the same antigenic determinant may be identified by a variety of techniques known in the art, such as by competitive binding studies using the cPAM4 antibody as the competing antibody and human pancreatic mucin or MUC5 AC as the target antigen.
  • Antibodies that block (compete for) binding to human pancreatic mucin by a cPAM4 antibody are referred to as cross- blocking antibodies.
  • cross-blocking antibodies are ones that bind to an epitope located within the second to fourth cysteine-rich subdomains of MUC5AC, or that compete for binding to amino acid residues 1575-2052 with a PAM4 antibody. More preferably, the antibodies bind to an epitope located in Cys2.
  • the therapeutic agent is selected from the group consisting of a radionuclide, an immunomodulator, a hormone, a hormone antagonist, an enzyme, an oligonucleotide such as an anti-sense oligonucleotide or a siRNA, an enzyme inhibitor, a photoactive therapeutic agent, a cytotoxic agent such as a drug or toxin, an angiogenesis inhibitor and a pro-apoptotic agent.
  • the therapeutic agents may comprise multiple copies of the same therapeutic agent or else combinations of different therapeutic agents. More preferably, the therapeutic agent is a radionuclide, such as W Y.
  • the labeled antibody may be administered alone, or in combination with one or more other therapeutic agents, such as low-dose gemcitabine.
  • the therapeutic agent is a cytotoxic agent, such as a drug or a toxin.
  • the drug is selected from the group consisting of nitrogen mustards, ethyienimine derivatives, alkyl sulfonates, nitrosoureas, gemcitabine, txiazenes, folic acid analogs, anthracyclines, taxanes, COX-2 inhibitors, pyrimidine analogs, purine analogs, antibiotics, enzyme inhibitors, epipodophyllotoxins, platinum coordination complexes, vinca alkaloids, substituted ureas, methyl hydrazine derivatives, adrenocortical suppressants, hormone antagonists, endostatin, taxols, camptothecins, SN-38, doxorubicins and their analogs, antimetabolites, alkylating agents, antimitotics, anti-angiogenic agents, tyrosine kinase inhibitors, Bruton
  • the therapeutic agent is a toxin selected from the group consisting of ricin, abrin, alpha toxin, saporin, ribonuclease (RNase), DNase I, Staphylococcal enterotoxin-A, pokeweed antiviral protein, gelonin, diphtheria toxin, Pseudomonas exotoxin, and Pseudomonas endotoxin and combinations thereof.
  • an immunomodulator selected from the group consisting of a cytokine, a stem cell growth factor, a l mphotoxin, a hematopoietic factor, a colony stimulating factor (CSF), an interferon (IFN), a stem ceil growth factor, erythropoietin, thrombopoietin and a
  • the therapeutic agent is an enzyme selected from the group consisting of malate dehydrogenase, staphylococcal nuclease, delta- V-steroid isomerase, yeast alcohol dehydrogenase, alpha- glycerophosphate dehydrogenase, triose phosphate isomerase, horseradish peroxidase, alkaline phosphatase, asparaginase, glucose oxidase, beta- galactosidase, ribonuclease, urease, catalase, glucose-6-phosphate dehydrogenase, glucoamylase and acetylcholinesterase.
  • Such enzymes may be used, for example, in combination with prodrugs that are administered in relatively non-toxic form and converted at the target site by the enzyme into a cytotoxic agent, in other alternatives, a drug may be converted into less toxic form by endogenous enzymes in the subject but may be reconverted into a cytotoxic form by the therapeutic enzyme.
  • Radionuclides such as 3 N, 15 0, 32 P, 3 '3 P. 47 S ic, Cr, ; i7 Co, 58 Co, 59 Fe, 62 Cu, 67 Cu, 67 Ga, 67 0a, 75 Br, 75 Se, " se, ' Br. 77 As, 77 Br, 80r 3 ⁇ 4r,
  • tyrosine kinase inhibitors include, but are not limited to canertinib, dasatinib, erlotinib, gefitinib, imatinib, lapatinib, leflunomide, nilotinib, pazopanib, semaxinib, sorafenib, sunitinib, sutent and vatalanib.
  • a specific class of tyrosine kinase inhibitor is the Bruton tyrosine kinase inhibitor.
  • Bruton tyrosine kinase (Btk) has a well- defined role in B-cell development.
  • Bruton kinase inhibitors include, but are not limited to, PCI- 32765 (ibrutinib), PCI-45292, GDC-0834, LFM-A13 and R 486.
  • the subject antibody or fragment may be conjugated to at least one diagnostic (or detection) agent.
  • the diagnostic agent is selected from the group consisting of a radionuclide, a contrast agent, a fluorescent agent, a chemiluminescent agent, a
  • the diagnostic agent is a radionuclide with an energy between 20 and 4,000 keV or is a radionuclide selected from the group consisting of ! " J in, l H In, ' ? 'Lu, i8 F, 52 Fe, 62 Cu, 64 Cu, 67 Cu, 67 Ga, 6 Ga, S6 Y, 9C' Y, 9 Zr, 94m Tc, 94 Tc, 99m Tc ; l *% i23 I, ⁇ 24 ⁇ , m L m l, i54 - i58 Gd, 52 P, !
  • the diagnostic radionuclide i8 F is used for labeling and PET imaging, as described in the Examples below.
  • the 18 F may be attached to an antibody, antibody fragment or peptide by ⁇ 8
  • the diagnostic agent is a paramagnetic ion, such as chromium (III), manganese (II), iron (III), iron (II), cobalt (II), nickel (II), copper (II), neodymium (III), samarium (HI), ytterbium (HI), gadolinium (HI), vanadium ( ⁇ ), terbium (HI), dysprosium (TCI), holmium (Hi) and erbium ( ⁇ ), or a radiopaque material, such as barium, diatrizoate, ethiodized oil, gallium citrate, iocarmic acid, iocetamic acid, iodamide, iodipamide, lodoxamic acid, iogulamide, iohexol, iopamidol, iopanoic acid, loprocemic acid, iosefamic acid, ioseric acid,
  • the diagnostic agent is a fluorescent labeling compound selected from the group consisting of fluorescein isothiocyanate, rhodamine, phycoerytherin, phycocyanin, allophycocyaniri, o-phthaldehyde and fluorescamine, a chemiluminescent labeling compound selected from the group consisting of luminoi, isoluminol, an aromatic acridinium ester, an imidazole, an acridinium salt and an oxalate ester, or a bioiuminescent compound selected from the group consisting of luciferin, lucif erase and aequorin.
  • the diagnostic immunoconjugates are used in intraoperative, endoscopic, or intravascular tumor diagnosis.
  • multivalent, multispeeific antibodies or fragments thereof comprising at least one binding site that binds to an epitope of MUC5AC as discussed above and one or more hapten binding sites having affinity towards hapten molecules.
  • the antibody or fragment thereof is a chimeric, humanized or fully human antibody or fragment thereof.
  • the hapten molecule may be conjugated to a targetable construct for delivery of one or more therapeutic and/or diagnostic agents.
  • the multivalent antibodies or fragments thereof may be prepared by the DOCK- A D-LOCKTM (DNLTM) technique, as described below.
  • DNLTM construct incorporating hPAM4 antibody fragments is designated TF 10, as described below.
  • a bispecific antibody or fragment thereof comprising at least one binding site with an affinity toward an epitope of MUC5 AC as discussed above and at least one binding site with an affinity toward a targetable construct which is capable of carrying at least one diagnostic and/or therapeutic agent.
  • Targetable constructs suitable for use are disclosed, for example, in U.S. Patent Nos.
  • fusion proteins comprising at least two anti-pancreatic cancer antibodies and fragments thereof as described herein.
  • the fusion protein or fragment thereof may comprise at least one first antibody or fragment thereof thai binds to an epitope of MUC AC as discussed above and at least one second MAb or fragment thereof.
  • the second MAb binds to a tumor-associated antigen, for example selected from the group consisting of CA19.9, DUPAN2, SPAN l , Nd2, B72.3, CC49, CEA (CEACAM5), CEACAM6, Le a , the Lewis antigen Le(y), CSAp, insulin-like growth factor (IGF), epithelial glycoprotein- 1 (EGP- 1 ), epithelial glycoprotein-2 (EGP-2), CD-80, placental growth factor (PIGF), carbonic anhydrase IX, tenascin, !L-6, HLA-DR, CD40, CD74 (e.g., milatuzumab), CD138 (syndecan-1), CTLA-4, PD- 1 , PD-Li, ⁇ -3, LAG-3, matrix metailoproteinase- i (MMP- 1 ), MMP-2, MMP-7, MMP-9, MMP- 14, MUCl , MUC2, M
  • DNA sequences comprising a nucleic acid encoding an anti- pancreatic cancer antibody, fusion protein, multispecific antibody, bispecific antibody or fragment thereof as described herein.
  • Other embodiments concern expression vectors and/or host cells comprising the antibody-encoding DNA sequences, in certain preferred embodiments, the host cell may be an Sp2/0 cell line transformed with a mutant Bcl-2 gene, for example with a triple mutant Bcl-2. gene (T69E, S70E, S87E), that has been adapted to cell transformation and growth in serum free medium. (See, e.g., U.S. Patent Nos. 7,531 ,327; 7,537,930; and 7,608,425, the Examples section of each of which is incorporated herein by reference.)
  • Another embodmient concerns methods of delivering a diagnostic or therapeutic agent, or a combination thereof, to a target comprising (i) providing a composition that comprises an anti-pancreatic cancer antibody or fragment that binds to an epitope located within the second to fourth cysteine-rich subdomains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575-1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575-1725 (Cys2+), most preferably, to an epitope located in Cys2, conjugated to at least one diagnostic and/or therapeutic agent and (ii) administering to a subject in need thereof the diagnostic or therapeutic conjugate of any one of the antibodies, antibody fragments or fusion proteins claimed herein.
  • a composition that comprises an anti-pancreatic cancer antibody or fragment that binds to an epitope located within the second to fourth cysteine-rich subdomains of MUC5
  • the carrier molecule binds to more than one binding site of the antibody.
  • Described herein is a method for diagnosing or treating cancer, comprising: (a) administering to a subject any one of the multivalent, multispecific antibodies or fragments thereof claimed herein that have an affinity toward an epitope of MUC5AC as discussed above and comprising one or more hapten binding sites; (b) waiting a sufficient amount of time for an amount of the non-bound antibody to clear the subject's blood stream; and (c) administering to said subject a carrier molecule comprising a diagnostic agent, a therapeutic agent, or a combination thereof, that binds to a binding site of the antibody.
  • the cancer is pancreatic cancer.
  • the method can be used for intraoperative identification of diseased tissues, endoscopic identification of diseased tissues, or intravascular identification of diseased tissues.
  • Another embodiment is a method of treating a malignancy in a subject comprising administering to said subject a therapeutically effective amount of an antibody or fragment thereof that binds to an epitope of MUC5AC as discussed above, optionally conjugated to at least one therapeutic agent, such as ' Y.
  • the antibody or fragment thereof may alternatively be a naked antibody or fragment thereof.
  • the antibody or fragment is administered either before, simultaneously with, or after administration of another therapeutic agent as described above.
  • [034] Contemplated herein is a method of diagnosing a malignancy in a subject, particularly a pancreatic cancer, comprising (a) administering to said subject a diagnostic conjugate comprising an antibody or fragment thereof that binds to an epitope of MUC5AC as discussed above, wherein said MAb or fragment thereof is conjugated to at least one diagnostic agent, and (b) detecting the presence of labeled antibody bound to pancreatic cancer ceils or other malignant cells, wherein binding of the antibody is diagnostic for the presence of pancreatic cancer or another malignancy.
  • the antibody or fragment binds to pancreatic cancer and not to normal pancreatic tissue, pancreatitis or other non-malignant conditions.
  • the antibody or fragment binds at a significantly higher level to cancer cells than to non-malignant cells, allowing differential diagnosis of cancer from non-malignant conditions.
  • the diagnostic agent may be an F- 18 labeled molecule that is detected by PET imaging.
  • the use of anti -pancreatic cancer antibodies that bind to an epitope located within the second to fourth cysteine-rich siibdomains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575-1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575-1725 (Cys2+), most preferably, to an epitope located in Cys2, allows the detection and/or diagnosis of pancreatic cancer with high specificity and sensitivity at the earliest stages of malignant disease.
  • the diagnostic antibody or fragment is capable of labeling at least 70%, more preferably at least 80%, more preferably at least 90%, more preferably at least 95%, most preferably about 100% of well differentiated, moderately differentiated and poorly differentiated pancreatic cancer and 90% or more of invasive pancreatic adenocarcinomas.
  • the anti-pancreatic cancer antibody of use is preferably capable of detecting 85% or more of PanTN-lA, PanIN-lB, PanIN-2, TPMN and MCN precursor lesions. Most preferably, immunoassays using the anti-pancreatic cancer antibody are capable of detecting 89% or more of total PanIN, 86% or more of IPMN, and 92% or more of MCN.
  • An alternative embodiment is a method of detecting the presence of PAM4-b hiding MUC5AC and/or diagnosing pancreatic cancer in an individual by in vitro analy sis of blood, plasma or serum samples.
  • the sample is subjected to an organic phase extraction, using an organic solvent such as butanol, before it is processed for immunodetection using an anti-pancreatic cancer antibody, such as a PAM4 antibody.
  • organic phase extraction the extracted aqueous phase is analyzed for the presence of the epitope of MUC5AC to which PAM4 binds in the sample, using any of a variety of immunoassay techniques known in the art, such as ELISA, sandwich immunoassay, solid phase RIA, and similar techniques.
  • the organic phase extraction results in the removal of an inhibitor of PAM4 binding to MUC5AC, allowing detection of MUC5 AC in fresh serum samples.
  • serum samples may be analyzed to detect and/or diagnose pancreatic cancer in a subject at the earliest stages of pancreatic adenocarcinoma.
  • Another embodiment is a method of treating a cancer cell in a subject comprising administering to said subject a composition comprising a naked antibody or fragment thereof or a naked antibody fusion protein or fragment thereof that binds to an epitope of MUC5AC as discussed above.
  • the method further comprises administering a second naked antibody or fragment thereof selected from the group consisting of CA 19.9, DUPAN2, SPAN1, Nd2, B72.3, CC49, anti-CEA, anti-CEACAM6, anti-EGP-1, anti-EGP-2, anti-Le 8 , antibodies defined by the Lewis antigen Le(y), and antibodies against CSAp, MUC1, MUC2, MUC3, MUC4, MUC5AC, ⁇ H . (. ' !
  • HLA-DR HLA-DR
  • CD74 CD 138
  • angiogenesis factors e.g., VEGF and placenta-lilve growth factor (PIGF), insulin-like growth factor (IGF), tenascin, platelet-derived growth factor, IL-6, products of oncogenes, cMET, and HER2/neu.
  • Still other embodiments concern a method of diagnosing a malignancy in a subject comprising (i) performing an in vitro diagnosis assay on a specimen from said subject with a composition comprising an antibody or fragment thereof that binds to an epitope of
  • the malignancy is a cancer. More preferably, the cancer is pancreatic cancer,
  • FIG. 1 Co-localization of PAM4 antigen with MUC5AC by cytoflurometrk staining.
  • Mucin-expressing cell lines Capan-1 , BxPC-3, HT-29, and MCF-7) were stained with DAPI, 2-1 1 M1 (anti-MUC5AC), hPAM4, and examined by immunofluorescence microcopy.
  • BxPC-3 and HT-29 ceils were also stained with anti-MUCl .
  • PAM4 antigen was shown to co-localize with MUC5AC, not MUC1.
  • FIG. 2 Co-knockdown of PAM4 antigen and MUC5AC by MUC5AC-specific siR A.
  • CFPAC-1 ceils were treated with a MUC5AC-specific siRNA, followed by immunostaimng with DAPI, hPAM4, and 2-1 1M1 (anti-MUC5 C), or with DAPI, hPAM4 and anti-MUC l .
  • Untreated Cells or cells treated with only the transfection agent (Mock) served as controls.
  • Cells treated with MUCSAC-specific siRNA lost the binding to anti- MLTC5AC and hPAM4 concurrently, with little effect on the binding to anti-MUCl.
  • FIG. 3A Immunoreactivity of fractions elated from SEPHAROSE® CL-2B. Capan-1 cell culture supernatant was separated on a SEPHAROSE® CL2B column with the eluted fractions analyzed by hPAM4 and anti-MUCl .
  • FIG, 3B Immunoreactivity of fractions eloted from SEPHAROSE® CL-2B.
  • the void-volume (Vo) fractions of Capan-1 reacted positively with three anti-MUC5AC antibodies (45M1, 1 - 13M1 and IT- i 60), but not with 2Q445, which recognizes the unglycosylated tandem repeat region of MUC5AC.
  • FIG. 3C Immunoreactivity of fractions elated from SEPHAROSE® CL-2B.
  • the Capan-1 void- volume peak, following capture by 2-1 1M1, could be detected directly by HRP-hPAM4, or indirectly by biotin-45Ml plus SA-HRP.
  • FIG. 4A Agarose gel electrophoresis.
  • the Capan-1 void-volume peak displayed the characteristic banding pattern of MUC5AC as revealed by Western blot analysis with hPAM4, 45M1, and MAN-5ACI.
  • samples in the lanes marked as 1, 1/2, 1/4, and 1/8 were tested undiluted, 2-, 4- and 8 -fold diluted, respectively.
  • the monomelic and dimeric MUC5AC were indicated as M and D, respectively.
  • FIG. 4B Agarose gel electrophoresis.
  • FIG. 5A Mapping the PAM4-reactive epitope on human MUC5AC.
  • FIG. SB Mapping the PAM4-reactive epitope on human MIJC5AC.
  • Lane m indicates samples from untransfected ceils.
  • FIG. 5C Mapping the PAM4-reactive epitope on human MUC5AC. Western blot of c-fragment (AA1218-2199), d-fragment (AA1218-1517) and e-fragment (AA1575-2052), with hPAM4, H160 and 45M1 antibodies. Lane m indicates samples from untransfected cells.
  • FIG. 5D Mapping the PAM4-reactive epitope on human MUC5AC.
  • Lane m indicates samples from untransfected cells.
  • FIG. 5E Mapping the PAM4-reactive epitope o human MUC5AC.
  • Lane m indicates samples from untransfected cells.
  • FIG. 6A SDS-PAGE and Western blot analyses of recombinant MUC5AC fragments expressed in E. colt. Four gels were run under similar conditions of SDS-PAGE. Gel was stained with coomassie blue. Samples, either reduced (R) or non-reduced (NR), were loaded at 500 ng/well; lane M, markers; lanes 1 & 3, Cys2-3-4 (AA1575-2052); lanes 2 &4, Cys2+ (AAl 575-1725).
  • R reduced
  • NR non-reduced
  • FIG. 6B SDS-PAGE and Western blot analyses of recombinant MUC5AC fragments expressed in E. coli.
  • Four gels were run under similar conditions of SDS-PAGE. Gel was transferred onto nitrocellulose membrane and stained with anti-Myc. Samples, either reduced (R) or non-reduced (NR), were loaded at 500 ng well; lane M, markers; lanes 1 & 3, Cys2-3-4 (AAl 575-2052); lanes 2 &4, Cys2+ (AA1575-1725).
  • FIG. 6C SDS-PAGE and Western blot analyses of recombinant MUC5AC fragments expressed in E, coli.
  • Four gels were run under similar conditions of SDS-PAGE. Gel was transferred onto nitrocellulose membrane and stained with hPAM4. Samples, either reduced (R) or non-reduced (NR), were loaded at 500 ng/well; lane M, markers; lanes i & 3, Cys2-3-4 (AA1575-2052); lanes 2 &4, Cys2+ (AAI575-1725).
  • FIG. 6D SDS-PAGE and Western blot analyses of recombinant MUC5AC fragments expressed in E, coif. Four gels were run under similar conditions of SDS-PAGE. Gel was transferred onto nitrocellulose membrane and stained with 1-13M1. Samples, either reduced (R) or non-reduced (NR), were loaded at 500 ng/well: lane M, markers; lanes 1 & 3, Cys2-3-4 (AAl 575-2052); lanes 2 &4, Cys2+ (AA1575-1725).
  • FIG. 7 Overall survival, Kaplan-Meier curves and time -point analyses for all 29 patients in Arm A ( 9o Y-clivatuzumab tetraxetan combined with low-dose gemcitabine) and all 29 patients in Arm B ( w Y--clivatuzurnab tetraxetan alone),
  • FIG, 8 A Variable region cDN A sequences- (SEQ ID NO:9) and the deduced amino acid sequences (SEQ ID NO: 10) of the murine PAM4 Vk.
  • Amino acid sequences encoded by the corresponding DNA sequences are given as one-letter codes below the nucleotide sequence. Numbering of the nucleotide sequence is on the right side. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule numbering is used for amino acid residues as shown by the numbering above the amino acid residues. The amino acid residues numbered by a letter are the insertion residues defined by Kabat numbering scheme. The insertion residues have the same preceding digits as that of the previous residue.
  • FIG. 8B Variable region cDNA sequence (SEQ ID NO: I I) and the deduced amino acid sequence (SEQ ID NO: 12.) of the murine PAM4 VII.
  • Amino acid sequences encoded by the corresponding DNA sequences are given as one-letter codes below the nucleotide sequence. Numbering of the nucleotide sequence is on the right side. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule numbering is used for amino acid residues as shown by the numbering above the amino acid residues. The amino acid residues numbered by a letter are the insertion residues defined by Kabat numbering scheme. The insertion residues have the same preceding digits as that of the previous residue.
  • FIG. 9A Amino acid sequence (SEQ ID NO: 13) of the chimeric P A VI -i (cPAM4) Vk. The sequences are given as one letter codes. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule number scheme is used to number the residues.
  • FIG. 9B Amino acid sequence (SEQ ID NO: 14) of the cPAM4 VH. The sequences are given as one letter codes. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule number scheme is used to number the residues.
  • FIG. 10A Alignment of the VK amino acid seq uences of the human antibody Walker (SEQ ID NO: 15) with PAM4 (SEQ ID NO: 10) and hPAM4 (SEQ ID NO: 16). Dots indicate the residues of PAM4 that are identical to the corresponding residues of the human or humanized antibodies. Boxed regions represent the CDR regions. Both N- and C-terminal residues (underlined) of hPAM4 are fixed by the staging vectors used. Kabat's Ig molecule number scheme is used to number the residues.
  • FIG. I OB Alignment of the VH amino acid sequences of the human antibody Wil2 (FR1 -3) (SEQ ID NO: 17) and NEWM (FR4) (SEQ ID NO: 18) with PAM4 (SEQ ID NO: 12) and hPAM.4 (SEQ ID NO: 19).
  • Dots indicate the residues of PAM4 that are identical to the corresponding residues of the human or humanized antibodies. Boxed regions represent the CDR regions.
  • Both N- and C-terminal residues (underlined) of hPAM4 are fixed by the staging vectors used, Kabat's Ig molecule number scheme is used to number the residues.
  • FIG. 11A DNA (SEQ ID NO:20) and amino acid (SEQ ID NO: 16) sequences of the humanized PAM4 (hPAM4) Vk. Numbering of the nucleotide sequence is on the right side. Amino acid sequences encoded by the corresponding DNA sequences are given as one-letter codes. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule numbering scheme is used for amino acid residues.
  • FIG. i lB DNA (SEQ ID NO:21) and amino acid (SEQ ID NO: 19) sequences of the hPAM4 VH. Numbering of the nucleotide sequence is on the right side. Amino acid sequences encoded by the corresponding DN A sequences are given as one-letter codes. The amino acid residues in the CDR regions are shown in bold and underlined. Kabat's Ig molecule numbering scheme is used for amino acid residues,
  • FIG. 12 Binding activity of humanized PAM4 antibody, hPAM4, as compared to the chimeric PAM4, cPAM4. hPAM4 is shown by diamonds and cPAM4 is shown by closed circles. Results indicate comparable binding activity of the hPAM4 antibody and cPAM4 when competing with l2:, I-cPAM4 binding to CaPanl antigens.
  • FIG. 13 PET ' /CT fusion images for a patient with inoperable metastatic pancreatic cancer treated with fractionated 9J Y-hPAM4 plus gemcitabine, before therapy (left side) and post-therapy (right side).
  • the circle indicates the location of the primary lesion, which shows a significant decrease in PET/CT intensity following therapy.
  • FIG. 14 3D PET images for a patient with inoperable metastatic pancreatic cancer treated with fractionated 90 Y-hPAM4 plus gemcitabine, before therapy (left side) and post- therapy (right side). Arrows point to the locations of the primary lesion (on right) and metastases (on left), each of which shows a significant decrease in PET image intensity after therapy with radiolabeled hPAM4 plus gemcitabine.
  • FIG. 15A In vivo imaging of tumors using an 11 'in-labeled diHSO peptide (IMP 288) with or without pretargeting TF I O bispecific anti-pancreatic cancer MUC5AC antibody.
  • FIG. ISA illustrates mice sho wing the location of tumors (arrow).
  • FIG. 15B In vivo imaging of tumors using an u 'in-labeled diHSG peptide (IMP 288) with or without pretargeting TF iO bispecific anti-pancreatic cancer MUC5AC antibody.
  • FIG. 15B shows the detected tumors with 1 1 'in- labeled IMP 288 in the presence (above) or absence (below) of TF IO bispecific antibody.
  • FIG. 16 Exemplary binding curves for TF 10, PAM4-IgG, PAM4-F(ab * ) 2 and a monovalent bsPAM4 chemical conjugate (PAM4-Fab' x anii-DTPA-Fab'). Binding to target mucin antigen was measured b ELISA assay.
  • FIG. 17A Immunoscintigraphy of CaPanl human pancreatic cancer xenografts (-0.25 g). An image of mice that were injected with bispecific TF iO (80 fig, 5.07 x 10 '" '° mol) followed 16 h later by administration of m In-IMP-288 (30 ⁇ € ' ⁇ , 5.07 X 10 "1 1 mol). The image was taken 3 h later. The intensity of the image background was increased to match the intensity of the image obtained when ' ⁇ ⁇ - ⁇ -288 was administered alone (30 ⁇ (3 ⁇ 4 5.07 X 10 mol).
  • FIG. 1 B Immunoscintigraphy of CaPanl human pancreatic cancer xenografts (-0.25 g). No targeting was observed in mice given " ⁇ - ⁇ -288 alone.
  • FIG. 17C Immunoscintigraphy of CaPa l human pancreatic cancer xenografts (-0.25 g). An image of mice that were given ' "ln-DOTA-PAM4-IgG (20 ⁇ , 50 ⁇ g) with imaging done 24 h later. Although tumors are visible, considerable background activity is still present at this time point,
  • FIG. 18A Extended biodistribution of 11 ! Tn-DOTA-PAM4-IgG (20 ⁇ &, 50 ,ug) and TFlO-pretargeted ! 11 m-IMP-288 (80 ⁇ tg, 5.07 x 10 "!0 mol TF 10 followed 16 h later with 30 ⁇ , 5.07 x 10 " " mol m in-IMP-288) in nude mice bearing CaPanl human pancreatic cancer xenografts (mean tumor weight +/- SD, 0.28 +/- 0.21 and 0.10 +/- 0.06 g for the pretargeting and IgG groups of animals, respectively) .
  • FIG. 18A Extended biodistribution of 11 ! Tn-DOTA-PAM4-IgG (20 ⁇ &, 50 ,ug) and TFlO-pretargeted ! 11 m-IMP-288 (80 ⁇ tg, 5.07 x 10 "!0 mol TF 10 followed 16 h later with
  • FIG. I8B Extended biodistribution of m In-DOTA-PAM4-IgG (20 ⁇ 3 ⁇ 4 50 ⁇ g) and TFlO-pretargeted ! l l In-IMP-288 (80 ⁇ g, 5.07 x i0 "i0 mol TF10 followed 16 h later with 30 ⁇ , 5.07 x 10 "u mol !
  • FIG. ⁇ 8B shows percent of initial dose per per gram of tissue in liver with PAM4 IgG (open triangles), kidney with PAM4 IgG (open diamonds), liver with pretargeted peptide (closed triangles) and kidney with pretargeted peptide (closed diamonds).
  • FIG. ISC Extended biodistribution of ' In-DOTA-PAM4-IgG (20 ⁇ (3 ⁇ 4 50 g) and TF 10-pretargeted m m-IMP-288 (80 ⁇ g, 5.07 x 1 ⁇ '! ° mol TF10 followed 16 h later with 30 ⁇ , 5.07 x 10 "! l mol ! " ⁇ - ⁇ -288) in nude mice bearing CaPanl human pancreatic cancer xenografts (mean tumor weight +/- SD, 0.28 +/- 0.21 and 0.10 +/- 0.06 g for the pretargeting and IgG groups of animals, respectively).
  • FIG. I8D Extended biodistribution of 1 l i In-DOTA-PAM4-IgG (20 ⁇ , 50 g) and TF10-pretargeted ! ! 1 ⁇ - ⁇ -288 (80 ⁇ g, 5.07 x 1 ⁇ '! ° mol TF10 followed 16 h later with 30 ⁇ , 5.07 x 10 "! l mol ! " ⁇ - ⁇ -288) in nude mice bearing CaPanl human pancreatic cancer xenografts (mean tumor weight +/- SD, 0.28 +/- 0.21 and 0.10 +/- 0.06 g for the pretargeting and IgG groups of animals, respectively).
  • 18D shows microcuries per per gram of tissue in liver with PAM4 IgG (open triangles), kidney with PAM4 IgG (open diamonds), liver with pretargeted peptide (closed triangles) and kidney with pretargeted peptide (closed diamonds).
  • FIG. 19 Tnerapeutic activiiy of a single treatment of established (-0.4 cm 3 ) CaPa l tumors with 0, 15 mCi of 90 Y-hPAM4 IgG, or 0.25 or 0.50 mCi of TF10-pretargeted 90 Y-IMP- 288.
  • FIG. 20 Effect of gemcitabine potentiation of PT-RAIT therapy .
  • FIG. 21 Effect of combination of cetuximab with gemcitabine and PT-RAIT.
  • FIG. 22 Differential diagnosis of pancreatic cancer using PAM4-based
  • the horizontal line shows the cutoff level selected for a positive result, based on ROC analysis.
  • FIG. 23 Frequency distribution of PAM4 antigen in patient sera from healthy volunteers and individuals with varying stages of pancreatic cancer.
  • FIG. 24 ROC curve for PAM4 serum immunoassay, showing sensitivity for detection of 81.6% and specificity of 84.6%.
  • FIG. 27 Receiver Operator Characteristics (ROC) cur v e for the performance of the PAM4-based immunoassay; pancreatic adenocarcinoma vs. healthy adults. Values for the area under the curves (AUG) and 95% confidence limits are provided.
  • ROC Receiver Operator Characteristics
  • FIG. 28A Circulating PAM4 antigen levels correlated with progression/regression of tumor volume (CT) following treatment with 90 Y-PAM4-IgG plus gemcitabine.
  • CT tumor volume
  • Patient 076- 001 was responsive to therapy and serum PAM4 antigen decreased.
  • Serum PAM4 levels correlated with tumor volume.
  • FIG. 28B Circulating PAM4 antigen levels correlated with progression regression of tumor volume (CT) following treatment with 0 Y-PAM4-IgG plus gemcitabine.
  • CT tumor volume
  • Serum PAM4 levels correlated with tumor volume.
  • FIG. 29 Reactivity of PAM4 with mucin standards in the presence or absence of palmitic acid.
  • FIG. 30A Sensitivity and specificity for PAM4 detection ofPDAC vs. chronic pancreatitis (CP).
  • FIG. SOB Sensitivity and specificity for PAM4 detection of PDAC vs. all benign tissue samples.
  • FIG. 31 Comparative labeling of PDAC vs. non-neoplastic prostate tissue with PAM4 vs. antibodies against MUC1, MUC4, CEACAM6 and CA19-9.
  • FIG. 32 Reactivity of several anti-mucin MAbs with a high molecular weight mucin containing fraction (CPM1) isolated from the Capan-1, human pancreatic adenocarcinoma. MAbs are identified by clone name with reactive species of mucin indicated by horizontal bars beneath MAb clone names. In addition to PAM4, substantial reactions were observed for anti-MUCl , MUC5 C, and CEACAM6 antibodies. All MAbs were employed at a constant 10 ⁇ ig/mL.
  • FIG. 33 Reaction of several anti-mucin MAbs with PAM4-captured antigen.
  • Mucin antigens were captured on hPAM4 coated plates, and then probed with several murine anti- mucin MAbs for reaction signal Both anti-MUC AC MAbs (2- 1M1 and 45M1) bound to the hPAM4-eaptured mucin, whereas the anti-MUCl MAbs (MAS and KC4) did not bind.
  • the homologous hPAM4/mPAM4, capture/probe immunoassay gave no signal, suggesting the density of PAM4 epitopes within the mucin may be low, possibly only a single site.
  • FIG. 34A Inhibition of hPAM4/antigen binding reaction by murine anti-mucin MAbs.
  • Anti-mucin mMAbs purified IgG
  • mPAM4 provided almost complete inhibition of the reaction between hPAM4 and antigen with the 45M1 anti-MUC5AC providing limited inhibitory affect (IC max - 25.5%).
  • IC max - 25.5% Neither 2-1 !Ml, anti-MUC5AC nor MA5 and KC4, anti- MUCl MAbs were able to inhibit the specific hPAM4/antigcn reaction.
  • FIG. 34B inhibition of hPAM4/antigen binding reaction by murine anti-mucin MAbs.
  • a similar inhibition study was performed with several anti-MUC5AC MAbs obtained as ascites fluids.
  • MAbs 21M1 , 62M1, and 463M1, anti-MUC5AC provided substantial inhibitory affect similar to that observed with mPAM4, IgG, self-inhibition.
  • the ascites form of 45MI yielded an inhibitory affect similar to that of the purified IgG.
  • Ascites containing anti-alpha fetoprotein was employed as a negative control.
  • FIG. 35 Representation of the domains of the MUC5AC glycoprotein with reactive epitopes indicated for several anti-MUC5AC MAbs.
  • Specific blocking studies suggest the PAM4-epitope resides within the cysteine-rich C-terminus domain.
  • the term "PAM4 antibody” includes murine, chimeric, humanized and human PAM4 antibodies.
  • the PAM4 antibody or antigen-binding fragment thereof comprises the CDR sequences of SEQ ID NO: ! to SEQ ID NO:6,
  • an “anti-pancreatic cancer antibody” is an antibody that exhibits the same diagnostic, therapeutic and binding characteristics as the PAM4 antibody.
  • the "anti-pancreatic cancer antibody” binds to an epitope located within the second to fourth cysteine-rich subdomains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1 75-1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575- 1725 (Cys2+), most preferably, to an epitope located in Cys2.
  • a “non-endocrine pancreatic cancer” generally refers to cancers arising from the exocrine pancreatic glands.
  • the term excludes pancreatic insulinomas and includes pancreatic carcinoma, pancreatic adenocarcinoma, adenosquamous carcinoma, squamous cell carcinoma and giant cell carcinoma and precursor lesions such as pancreatic intra-epithelial neoplasia (PanIN), mucinous cyst neoplasms (MCN) and intrapancreatic mucinous neoplasms (IPMN), which are neoplastic but not yet malignant.
  • Pancreatic cancer and “non-endocrine pancreatic cancer” are used interchangeably herein,
  • An antibody refers to a full-length (i.e., naturally occurring or formed by normal immunoglobulin gene fragment recombinatorial processes)
  • immunoglobulin molecule e.g., an IgG antibody
  • immunologically active (i.e., specifically binding) portion of an immunoglobulin molecule like an antibody fragment.
  • An antibody fi'agment is a portion of an antibody such as F(ab')2, Fab', Fab, Fv, sFv and the like. Regardless of structure, an antibody fragment binds with the same antigen that is recognized by the full-length antibody.
  • the term "antibody fragment” also includes isolated fragments consisting of the variable regions of antibodies, such as the "Fv” fragments consisting of the variable regions of the heavy and light chains and recombinant single chain polypeptide molecules in which light and heavy variable regions are connected by a peptide linker ("scFv proteins"). Another form of antibody fragment is a single domain antibody (nanobody).
  • a naked antibody is an antibody or fragment thereof that is not conjugated to a therapeutic or diagnostic agent.
  • the Fc portion of the antibody molecule provides effector functions, such as complement-mediated cytotoxicity (CDC) and ADCC (antibody- dependent cellular cytotoxicity), which set mechanisms into action that may result in cell lysis.
  • CDC complement-mediated cytotoxicity
  • ADCC antibody- dependent cellular cytotoxicity
  • the Fc portion may not be required for therapeutic function, with other mechanisms, such as signaling- induced apoptosis, coming into play.
  • naked antibodies include both polyclonal and monoclonal antibodies, as well as fusion proteins and certain recombinant antibodies, such as chimeric, humanized or human antibodies.
  • a chimeric antibody is a recombinant protein that contains the variable domains including the complementarity determining regions (CDRs) of an antibody derived from one species, preferably a rodent antibody, while the constant domains of the antibody molecule are derived from those of a human antibody.
  • the constant domains of the chimeric antibody may be derived from that of other species, such as a cat or dog.
  • a humanized antibody is a recombinant protein in which the CDRs from an antibody from one species; e.g., a rodent antibody, are transferred from the heavy and light variable chains of the rodent antibody into human heavy and light variable domains (e.g., framework region sequences).
  • the constant domains of the antibody molecule are derived from those of a human antibody.
  • a limited number of framework region amino acid residues from the parent (rodent) antibody may be substituted into the human antibody framework region sequences.
  • a human antibody is, e.g., an antibody obtained from transgenic mice that have been "engineered” to produce specific human antibodies in response to antigenic challenge.
  • elements of the human heavy and light chain loci are introduced into strains of mice deri v ed from embryonic stem cell lines that contain targeted disruptions of the endogenous murine heavy chain and light chain loci.
  • the transgenic mice can synthesize human antibodies specific for particular antigens, and the mice can be used to produce human antibody- secreting hybridomas.
  • Methods for obtaining human antibodies from transgenic mice are described by Green et al., Nature Genet. 7: 13 (1994), Lonberg et al., Nature 368:856 (1994), and Taylor et al., Int. Immun.
  • a fully human antibody also can be constructed by genetic or chromosomal transfeclion methods, as well as phage display technology, all of which are known in the art. See for example, McCafferty et al., Nature 348:552-553 (1990) for the production of human antibodies and fragments thereof in vitro, from immunoglobulin variable domain gene repertoires from unimmunized donors, in this technique, antibody variable domain genes are cloned in-frame into either a major or minor coat protein gene of a filamentous bacteriophage, and displayed as functional antibody fragments on the surface of the phage particle.
  • the filamentous particle contains a single-stranded DNA copy of the phage genome, selections based on the functional properties of the antibody also result in selection of the gene encoding the antibody exhibiting those properties. In this way, the phage mimics some of the properties of the B cell.
  • Phage display can be performed in a variety of formats, for review, see e.g. Johnson and Cniswell, Current Opinion in Structural Biology 3:5564-571 (1993).
  • Human antibodies may also be generated by in vitro activated B cells. See U.S. Pat. Nos. 5,567,610 and 5,229,275, the Examples sections of which are incorporated herein by reference,
  • a therapeutic agent is a compound, molecule or atom which is administered separately, concurrently or sequentially with an antibody moiety or conjugated to an antibody moiety, i.e., antibody or antibody fragment, or a subfragment, and is useful in the treatment of a disease.
  • therapeutic agents include antibodies, antibody fragments, cytotoxic agents, drugs, toxins, nucleases, hormones, immunomodulators, pro-apoptotic agents, anti-angiogenic agents, boron compounds, photoactive agents or dyes and radioisotopes. Therapeutic agents of use are described in more detail below,
  • a diagnostic agent is a molecule, atom or other detectable moiety which may be administered conjugated to an antibody moiety or targetable construct and is useful in detecting or diagnosing a disease by locating ceils containing the target antigen.
  • useful diagnostic agents include, but are not limited to, radioisotopes, dyes, contrast agents, fluorescent compounds or molecules and enhancing agents (e.g., paramagnetic ions) for magnetic resonance imaging (MRI) or positron emission tomography (PET) scanning.
  • the diagnostic agents are selected from the group consisting of radioisotopes, enhancing agents for use in magnetic resonance or PET ' imaging, and fluorescent compounds.
  • a reagent having a long tail to which are attached a multiplicity of chelating groups for binding the ions.
  • a tail can be a polymer such as a polylysine, polysaccharide, or other derivatized or derivatizable chain having pendant groups to which can be bound chelating groups such as, e.g.,
  • EDTA ethyienediaminetetraacetic acid
  • DTP A diethylenetriaminepentaacetic acid
  • DOT A DOT A
  • NQTA DOT A
  • NET A NET A
  • porphyrins polyamines, crown ethers, bis-thiosemicarbazones, polyoximes, and like groups known to be useful for this purpose.
  • Chelates are coupled to the antibodies using standard chemistries.
  • the chelate is normally linked to the antibody by a group which enables formation of a bond to the molecule with minimal loss of
  • metal-chelate combinations include 2-benzyl-DTPA and its monomethyl and eyciohcxyl analogs, used with diagnostic isotopes in the general energy range of 60 to
  • Macrocyclic chelates such as NOT A (1 ,4,7-triazaeyclononane- ⁇ , ⁇ ', ⁇ ''-triacetic acid), DOTA (1 ,4,7, 10-tetraazacyclododecanetetraacetic acid), and TETA (p -brcunoaceiamido-benzyl-tetraethylaminetetraacetic acid) are of use with a variety of metals and radiometals, most particularly with radionuclides of gallium, yttrium and copper, respectively. Such metal-chelate complexes can be made very stable by tailoring the ring size to the metal of interest.
  • ring-type chelates such as macrocyclic polyethers, which are of interest for stably binding nuclides, such as *'*'3 a for radioimmunotherapy (RAIT) are encompassed by the invention. More recently, techniques of general utility for labeling virtually any molecule with an i8 F atom of use in PET imaging have been described in U.S. Patent Nos. 7,563,433; 7,597,876 and 7,993,626, the Examples section of each incorporated herein by reference.
  • An immunoconjugate is an antibody, antibody fragment or antibody fusion protein conjugated to at least one therapeutic and/or diagnostic agent.
  • the diagnostic agent and/or therapeutic agent are as defined above.
  • An expression vector is a DNA molecule comprising a gene that is expressed in a host cell. Typically, gene expression is placed under the control of certain regulatory elements, including constitutive or inducible promoters, tissue-specific regulatory elements and enhancers. Such a gene is said to be "operably linked to" the regulatory elements,
  • a recombinant host may be any prokaryotic or eukaryotic cell that contains either a cloning vector or expression vector. This term also includes those prokaryotic or eukaryotic cells, as well as transgenic animals, that have been genetically engineered to contain the cloned gene(s) in the chromosome or genome of the host cell.
  • Suitable mammalian host cells include myeloma cells, such as SP2/0 cells, and NS0 cells, as well as Chinese Hamster Ovary (CHO) cells, hybridoma cell lines and other mammalian host cell useful for expressing antibodies.
  • Sp2/0 ceils transfected with an apoptosis inhibitor, such as a Bcl-EEE gene, and adapted to grow and be further transfected in serum free conditions, as described in U.S. Patent Nos. 7,531,327; 7,537,930; and 7,608,425, the Examples section of each of which is incorporated herein by reference.
  • Various embodiments of the invention concern antibodies that react with very high selectivity with pancreatic cancer as opposed to normal or benign pancreatic tissues.
  • the anti- pancreatic cancer antibodies and fragments thereof are preferably raised against a crude mucin preparation from a tumor of the human pancreas, although partially purified or even purified MUC AC may be utilized.
  • a non-limiting example of such antibodies is the PAM4 antibody.
  • the murine PAM4 (mPAM4) antibody was developed by employing pancreatic cancer mucin derived from the xenografted RIP-1 human pancreatic carcinoma as immunogen. (Gold et al., Int. J. Cancer, 57:204-210, 1994.) As discussed below, antibody cross-reactivity and immunohistochemicai staining studies indicate that the PAM4 antibody recognizes a unique and novel epitope on MUC5AC. Immunohistochemicai staining studies have shown that the PAM4 MAb binds to an antigen expressed by breast, pancreas and other cancer ceils, with limited binding to normal human tissue. Howe ver, the highest expression is usually by pancreatic cancer cells.
  • the PAM4 antibodies are relatively specific to pancreatic cancer and preferentially bind pancreatic cancer cells.
  • the PAM4 antibody is reactive with a target epitope which can be internalized. This epitope is expressed primarily by antigens associated with pancreatic cancer and not with focal pancreatitis or normal pancreatic tissue. Binding of PAM4 antibody to the PAM4 epitope is inhibited by treatment of the antigen with DTT or periodate. Localization and therapy studies using a radiolabeled PAM4 MAb in animal models have demonstrated tumor targeting and therapeutic efficacy.
  • the PAM4 antibodies bind to an epitope located within the second to fourth cysteine - rich subdomains of MUC5 AC (amino acid residues 1 75-2052), more preferably to an epitope located in amino acid residues 1575-1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575-1725 (Cys2+), most preferably, to an epitope located in Cys2.
  • the PAM4 epitope is expressed by many organs and tumor types, but is preferentially expressed in pancreatic cancer cells. Studies with a PAM4 MAb, as in the Examples below, indicate that the antibody exhibits several important properties, which make it a good candidate for clinical diagnostic and therapeutic applications.
  • the epitope provides a useful target for diagnosis and therapy of pancreatic and other cancers.
  • the PAM4 antibody apparently recognizes an epitope of MUC5AC that is distinct from the epitopes recognized by non-PAM4 anti-pancreatic cancer antibodies (e.g., CA19.9, DUPAN2, SPAM, Nd2, CEACAM5, B72.3, anti-Le a , and other anti-Lewis antigens).
  • non-PAM4 anti-pancreatic cancer antibodies e.g., CA19.9, DUPAN2, SPAM, Nd2, CEACAM5, B72.3, anti-Le a , and other anti-Lewis antigens.
  • the Examples below indicate that the MUC5AC epitope to which PAM4 binds is present in detectable concentrations in serum of patients with very early stage pancreatic cancer. Also surprisingly, it appears that an endogenous inhibitor of PAM4 antibody binding to MUC5AC is present in fresh human serum. The inhibitor is removed by long-term frozen storage of serum samples, or by organic phase extraction of fresh serum. These unexpected results provide the basis of a relatively non-invasive, early detection test for pancreatic cancer, using blood, serum or plasma samples.
  • the PAM4 antibody may be used alone, or else in conjunction with one or more other antibodies, such as CA19.9 antibody, to detect pancreatic cancer markers in serum.
  • PAM4 At the tissue level, the reactivity of PAM4 is highly restricted to PDAC, with the biomarker expressed (or becomes accessible) at the earliest stages of neoplastic devel opment (Gold et al., 1994, Int J Cancer 57:204-10; Gold et al., 2007, Clin Cancer Res 13:7380-7), including pancreatic intraepithelial neoplasia (PanIN), and intraductal papillary mucinous neoplasm (IPMN).
  • PAM4-biomarker is absent from normal pancreas and benign, non-neoplastic lesions.
  • the PAM4-biomarker was identified only within associated PanIN lesions and not by the inflamed parenchyma, including ducts, acinar ceils, and acinar-ductal metaplasia (Shi et al., 2014, Arch Pathol Lab Med 138:220-8).
  • 90 Y-iaheied, humanized PAM4 ( 90 Y-clivatuzumab tetraxetan, hereafter referred to as 90 Y- hPAM4) was well tolerated with manageable hematologic toxicity under maximal tolerated W Y dosing, and produced objective responses in both chemotherapy-naive and -refractory patients with advanced PDAC (Gulec et al., 201 1 , Clin Cancer Res 17:4091-100). Further, 9u Y-hPAM4 in combination with low-dose gemcitabine showed enhanced therapeutic efficacy in patients with metastatic pancreatic cancer (Ocean et al., 2012, Cancer 118:5497- 506).
  • PAM4 or hPAM4-based ELISA has been devised and evaluated for detection of PDAC, showing that nearly two-thirds of patients having confirmed stage - 1 disease had elevated PAM4 antigen in their serum (Gold et a!., 2 10, Cancer Epidemiol Biomarkers Prev 19:2786-94).
  • the current assay which employs hPAM4 as the capture antibody and a polyclonal rabbit anti-mucin antiserum (IgG fraction) as a probe, is not optimal, because the polyclonal probe is available in only limited quantities and, more importantly, is not itself specific for the PAM4 antigen.
  • antibodies suitable for use in combination or conjunction with PAM4 antibodies include, for example, the antibodies CA19.9, DUPAN2, SPAM 1, Nd2, B72.3, CC49, anti-CEA, anti-CEACAM6, anti-Le 8 , anti-HLA-DR, anti-CD40, anti-CD74, anti-CD 138, and antibodies defined by the Lewis antigen Leiy), or antibodies against colon- specific antigen-p (CSAp), CTLA-4, PD-1, PD-LL TIM-3, LAG-3, matrix
  • MMP-l metalloproteinase-1
  • MMP-2 MMP-7
  • MMP-9 MMP- 14, MUC 1, MUC2, MUC3, MUC4, MUC5A.C, MUC16, MUG 17, EGP-1 , EGP-2, HER2/neu, EGFR, angiogenesis factors (e.g., VEGF and PIGF), insulin-like growth factor (IGF), tenascin, platelet-derived growth factor, and IL-6, as well as products of oncogenes (bcl-2, Kras, p53), cMET, and antibodies against tumor necrosis substances, such as described in patents by Epstein et al. (U.S. Pat. Nos.
  • Immunomodulators involved in effector cell function against tumor cells could also be useful in combination with PAM4 antibodies alone or in combination with other tumor-associated antibodies, one example being antibodies against CD40.
  • Also of use are antibodies against markers or products of oncogenes (e.g., bcl-2, Kras, p53, cMET), or antibodies against angiogenesis factors, such as VEGFR and placenta-like growth factor (P1GF).
  • the murine, chimeric, humanized and fully human PAM4 antibodies and fragments thereof described herein are exemplary of anti-pancreatic cancer antibodies of use for diagnostic and/or therapeutic methods.
  • the Examples below disclose a preferred embodiment of the construction and use of a humanized PAM4 antibody.
  • humanization of a murine antibody sequences can reduce the adverse immune response that patients may experience.
  • this is often referred to as a Human Anti-Mouse Antibody (HAMA) response.
  • HAMA Human Anti-Mouse Antibody
  • the humanized anti- pancreatic cancer antibody or fragments thereof are replaced by their murine counterparts. It is also preferred that a combination of framework sequences from two different human antibodies is used for VR.
  • the constant domains of the antibody molecule are derived from those of a human antibody.
  • Monoclonal antibodies for specific antigens may be obtained by methods known to those skilled in the art. See, for example. Kohler and Milstem, Nature 256: 495 ( 1975), and Coligan et al. (eds.), CURRENT PROTOCOLS IN IMMUNOLOGY, VOL. 1, pages 2.5.1 - 2.6.7 (John Wiley & Sons 1991 ) (hereinafter "Coligan").
  • anti -pancreatic cancer MAbs can be obtained by injecting mice with a composition comprising a mixture of pancreatic cancer mucins comprising MUC5AC, or a purified MXJC5AC, or a peptide or protein corresponding to an epitope located within the second to fourth cysteine -rich domains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575- 1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575- 1725 (Cys2+), most preferably, to an epitope located in Cys2, verifying the presence of antibody production by removing a serum sample, removing the spleen to obtain B-lympbocytes, fusing the B-lympbocytes with myeloma cells to produce hybridomas, cloning the hybridomas, selecting positive clones which produce antibodies to MUC5
  • the antibodies can be sequenced and subsequently prepared by recombinant techniques to produce chimeric or humanized antibodies. Chimerization of murine antibodies and antibody fragments are well known to those skilled in the art. The use of antibody components derived from chimerized monoclonal antibodies reduces potential problems associated with the immunogenicity of murine constant regions.
  • V (variable light chain) and VH (variable heavy chain) sequences for murine antibodies can be obtained by a variety of molecular cloning procedures, such as RT-PCR, 5'-RACE, and cDNA library screening. Specifically , the VH and V sequences of the murine PAM4 MAb were cloned by PCR amplification from the hybridoma cells by RT-PCR, and their sequences determined by DN A sequencing.
  • V K and V H genes can be expressed in cell culture as a chimeric Ab as described by Orlandi et al., (Proc Natl. Acad. Sci., USA, 86: 3833, 1989).
  • a chimerized PAM4 antibody or antibody fragment comprises the complementarity-determining regions (CDRs) and framework regions (FR) of a murine PAM4 MAb and the light and heavy chain constant regions of a human antibody, wherein the CDRs of the light chain v ariable region of the chirnerized PAM4 comprises CDR l (SASSSVSSSYLY, SEQ ID NO: 3 ); CDR2 (ST8NLA8, SEQ ID NO:2); and CDR3 (HQWNRYPYT, SEQ ID NO:3); and the CDRs of the heavy chain variable region of the chirnerized PAM4 MAb comprises CDRl (SYVLH, SEQ ID NO:4); CDR2
  • humanized monoclonal antibodies may be produced by transferring murine complementary determining regions from heavy and light variable chains of the mouse immunoglobulin into a human variable domain, and then substituting selected human residues in the framework regions with their the murine FR counterparts.
  • the use of human framework region sequences, in addition to human constant region sequences, further reduces the cha ce of inducing PIAMA reactions.
  • Humanized antibodies can be designed and constructed as described by Leung et al. (Mol Immunol. 32: 1413 (1995)).
  • Example 3 describes the humanization process utilized for construction of the hPAM4 MAb.
  • a humanized PAM4 antibody or antibody fragment comprises the light and heavy chain CDR sequences (SEQ ID NO: l to SEQ ID NO: 6) disclosed above.
  • the FRs of the light and heavy chain variable regions of the humanized antibody comprise at least one amino acid substituted from said corresponding FRs of the murine PAM4 MAb.
  • a fully human antibody e.g., human PAM4 can be obtained from a transgenic non- human animal. See, e.g., Mendez et al., Nature Genetics, 15: 146- 156 (1997); U.S. Pat. No. 5,633,425.
  • a human antibody can be recovered from a transgenic mouse possessing human immunoglobulin loci.
  • the mouse humoral immune system is humanized by inactivating the endogenous immunoglobulin genes and introducing human immunoglobulin loci.
  • the human immunoglobulin loci are exceedingly complex and comprise a large number of discrete segments which together occupy almost 0.2% of the human genome.
  • YACs yeast artificial chromosomes
  • each insert is approximately 1 Mb in size.
  • YAC construction requires homologous recombination of overlapping fragments of the immunoglobulin loci.
  • the two YACs, one containing the heavy-chain loci and one containing the light-chain loci, are introduced separately into mice via fusion of YAC-containing yeast spheroblasts with mouse embryonic stem cells.
  • Embryonic stem cell clones are then microinjected into mouse blastocysts. Resulting chimeric males are screened for their ability to transmit the YAC through their germline and are bred with mice deficient in murine antibody production. Breeding the two transgenic strains, one containing the human heavy- chain loci and the other containing the human light-chain loci, creates progeny which produce human antibodies in response to immunization.
  • these techniques are not limiting and other methods known in the art for producing human antibodies, such as the use of phage display, may also be utilized to produce human anti-pancreatic cancer antibodies.
  • Antibodies can be produced by cell culture techniques using methods known in the art.
  • transfectoma cultures are adapted to serum-free medium.
  • cells may be grown as a 500 ml culture in roller bottles using HSFM, Cultures are centrifuged and the supernatant filtered through a 0.2 ⁇ membrane. The filtered medium is passed through a protein- A column (1 x 3 cm) at a flow rate of 1 ml/min. The resin is then washed with about 10 column volumes of PBS and protein A-bound antibody is eluted from the column with O. i M glycine buffer (pH 3.5) containing 10 mM EDTA.
  • Fractions of i .O ml are collected in tubes containing 10 ⁇ of 3 M Tris (pH 8.6), and protein concentrations determined from the absorbance at 280/260 nm. Peak fractions are pooled, dialyzed against PBS, and the antibody concentrated, for example, with a Centricon 30 filter (Amicon, Beverly, MA). The antibody concentration is determined by ELISA and its concentration adjusted to about 1 mg/ml using PBS. Sodium azide, 0.01 % (w/v), is conveniently added to the sample as preservative.
  • Antibodies can be isolated and purified from hybridoma cultures by a variety of well-established techniques. Such isolation techniques include affinity chromatography with Protein-A SEPHAROSE®, size-exclusion chromatography, and ion-exchange
  • Anti-pancreatic cancer MAbs can be characterized by a variety of techniques that are well-known to those of skill in the art. For example, the ability of an antibody to bind to an epitope of MUC5AC as discussed above can be verified using an indirect enzyme immunoassay, flow cytometry analysis, ELISA or Western blot analysis.
  • Antibody fragments are antigen binding portions of an antibody, such as F(ab') Fab', F(ab) 2 , Fab, Fv, sFv, scFv and the like. Antibody fragments which recognize specific epitopes can be generated by known techniques. F(ab') 2 fragments, for example, can be produced by pepsin digestion of the antibody molecule. These and other methods are described, for example, by Goldenberg, U.S. Pat Nos. 4,036,945 and 4,333 ,647 and references contained therein. Also, see Nisonoff et al., Arch Biochem. Biopbys. 89: 230 (1960); Porter, Biochem. J.
  • Fab' expression libraries can be constructed (Huse et at, 1989, Science, 246: 1274-1281) to allow rapid and easy identification of monoclonal Fab' fragments with the desired specificity.
  • a single chain Fv molecule comprises a VL domain and a VH domain.
  • the VL and VH domains associate to form a target binding site. These two domains are further covalently linked by a peptide linker (L).
  • L peptide linker
  • a scF v molecule is denoted as either VL-L-VH if the VL domain is the N-terminal part of the scFv molecule, or as VH-L-VL if the VH domain is the N-terminal part of the scFv molecule.
  • Single domain antibodies may ⁇ be obtained, for example, from camels, alpacas or llamas by standard immunization techniques. (See, e.g., Muyldermans et al., TIBS 26:230-235, 2001; Yau et al, J Immunol Methods 281 : 161 -75, 2003; Maass et al., J Immunol Methods 324: 13-25, 2007).
  • the VHH may have potent antigen-binding capacity and can interact with novel epitopes that are inaccessible to conventional V H -V L pairs.
  • Alpaca serum IgG contains about 50% camelid heavy chain only IgG antibodies (HCAbs) (Maass et al., 2007).
  • Alpacas may be immunized with known antigens, such as TNF-a, and VHHs can be isolated that bind to and neutralize the target antigen (Maass et al., 2007).
  • PGR primers that amplify virtually all alpaca VIIH coding sequences have been identified and may be used to construct alpaca VHH phage display libraries, which can be used for antibody fragment isolation by standard biopanning techniques well known in the art (Maass et al, 2007).
  • Commercially available single domain antibodies, also known as nanobodies may be purchased for example from Ablynx (Ghent, Belgium).
  • An antibody fragment can also be prepared by proteolytic hydrolysis of a full-length antibody or by expression in E. coli or another host of the DNA coding for the fragment.
  • An antibody fragment can be obtained by pepsin or papain digestion of full-length antibodies by conventional methods.
  • an antibody fragment can be produced by enzymatic cleavage of antibodies with pepsin to provide an approximate 100 Kd fragment denoted F(ab') 2 .
  • This fragment can be further cleaved using a thiol reducing agent, and optionally a blocking group for the sulfhydryl groups resulting from cleavage of disulfide linkages, to produce an approximate 50 Kd Fab' monovalent fragment.
  • an enzymatic cleavage using papain produces two monovalent Fab fragments and an Fc fragment directly.
  • Fusion proteins comprising the anti-pancreatic cancer antibodies of interest can be prepared by a variety of conventional procedures, ranging from glutaraldehyde linkage to more specific linkages between functional groups.
  • the antibodies and/or antibody fragments that comprise the fusion proteins described herein are preferably covalently bound to one another, directly or through a linker moiety, through one or more functional groups on the antibody or fragment, e.g., amine, carboxyl, phenyl, thiol, or hydroxy! groups.
  • linkers in addition to glutaraldehyde can be used, e.g., diisocyanates, diiosothiocyanates, bis(hydroxysuccinimide)esters, carbodlimides, maleimidehydroxy succinimide esters, and the like.
  • a simple method for producing fusion proteins is to mix the antibodies or fragments in the presence of glutaraldehyde.
  • the initial Schiff base linkages can be stabilized, e.g., by borohydride reduction to secondary amines.
  • a diiosothiocyanate or carbodiimide can be used in place of glutaraldehyde as a on-site-specific linker.
  • an antibody fusion protein comprises an anti-pancreatic cancer MAb, or fragment thereof, wherein the MAb binds to an epitope located within the second to fourth cysteine-rich domains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575-1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1 75-1725 (Cys2+), most preferably, to an epitope located in Cys2.
  • This fusion protein and fragments thereof preferentially bind pancreatic cancer cells.
  • This monovalent, monospecific MAb is useful for direct targeting of an antigen, where the MAb is attached to a therapeutic agent, a diagnostic agent, or a combination thereof, and the protein is administered directly to a patient.
  • the fusion proteins may instead comprise at least two anti-pancreatic cancer MAbs that bind to distinct epitopes of MUC5AC.
  • the MAbs can produce antigen specific diabodies, triabodies and tetrabodies, which are multivalent but monospecific to the MUC5AC.
  • the non-covalent association of two or more scFv molecules can form functional diabodies, triabodies and tetrabodies.
  • Monospecific diabodies are homodimers of the same scFv, where each scFv comprises the V K domain from the selected antibody connected by a short linker to the VL domain of the same antibody.
  • a diabody is a bivalent dimer formed by the non-covalent association of two scFvs, yielding two Fv binding sites
  • a triabody results from the formation of a trivalent trimer of three scFvs, yielding three binding sites
  • a tetrabody is a tetravalent tetramer of four scFvs, resulting in four binding sites.
  • the multivalent, monospecific antibody fusion protein binds to two or more of the same type of epitopes that can be situated on the same antigen or on separate antigens.
  • the increased valency allows for additional interaction, increased affinity, and longer residence times.
  • These antibody fusion proteins can be utilized in direct targeting systems, where the antibody fusion protein is conjugated to a therapeutic agent, a diagnostic agent, or a combination thereof, and administered directly to a patient in need thereof.
  • a preferred embodiment is a multivalent, multispecifie antibody or fragment thereof comprising one or more antigen binding sites having an affinity toward a PAM4 target epitope and one or more additional binding sites for other epitopes associated with pancreatic cancer.
  • This fusion protein is multispecifie because it binds at least two different epitopes, which can reside on the same or different antigens.
  • the fusion protein may comprise more than one antigen binding site, the first with an affinity toward an epitope of MUC5AC as discussed above and the second with an affinity toward another target antigen such as TAG-72 or CEA.
  • bispecific antibody fusion protein which may comprise a CA19.9 MAb (or fragment thereof) and a PAM4 MAb (or fragment thereof).
  • a fusion protein will have an affinity toward CA19.9 as well as MUC5AC.
  • the antibody fusion proteins and fragments thereof can be utilized in direct targeting systems, where the antibody fusion protein is conjugated to a therapeutic agent, a diagnostic agent, or a combination thereof, and administered directly to a patient in need thereof.
  • Another preferred embodiment is a multivalent, multispecifie antibody comprising at least one binding site having affinity toward a PAM4 target epitope and at least one hapten binding site having affinity towards hapten molecules.
  • a bispecific fusion protein may comprise the 679 MAb (or fragment thereof) and the PAM4 MAb (or fragment thereof).
  • the monoclonal 679 antibody binds with high affinity to molecules containing the tri-peptide moiety histamine succinyl glycyl (HSG).
  • HSG histamine succinyl glycyl
  • Such a bispecific PAM4 antibody fusion protein can be prepared, for example, by obtaining a F(ab') 2 fragment from 679, as described above.
  • the interchain disulfide bridges of the 679 F(ab') 2 fragment are gently reduced with DTT, taking care to avoid light-heavy chain linkage, to form Fab'-SH fragments.
  • the SH group(s) is (are) activated with an excess of bis-maleimide linker (l ,i'-(methylenedi-4, l- phenylene)b-is-maleimide).
  • the PAM4 MAb is converted to Fab'-SH and then reacted with the activated 679 Fab'-SH fragment to obtain a bispecific antibody fusion protein.
  • Bispecific antibody fusion proteins such as this one can be utilized in affinity enhancing systems, where the target antigen is pretargeted with the fusion protein and is subsequently targeted with a diagnostic or therapeutic agent attached to a carrier moiety (target able construct) containing one or more HSG haptens.
  • a DNLTM-based hPAM4- 679 construct such as TF 10, may be prepared and used as described in the Examples below.
  • Bispeciflc antibodies can be made by a variety of conventional methods, e.g., disulfide cleavage and reformation of mixtures of whole IgG or, preferably F(ab') 2 fragments, fusions of more than one hybridoma to form polyomas that produce antibodies having more than one specificity, and by genetic engineering.
  • Bispeciflc antibody fusion proteins have been prepared by oxidative cleavage of Fab' fragments resulting from reductive cleavage of different antibodies.
  • This is advantageously carried out by mixing two different F(ab') 2 fragments produced by pepsin digestion of two different antibodies, reductive cleavage to form a mixture of Fab' fragments, followed by oxidative reformation of the disulfide linkages to produce a mixture of F(ab') 2 fragments including bispeciflc antibody fusion proteins containing a Fab' portion specific to each of the original epitopes.
  • General techniques for the preparation of antibody fusion proteins may be found, for example, in Nisonoff et al., Arch Biochem Biophys. 93: 470 (1961), Hammerling et al, J Exp Med. 128: 1461 ( 1968), and U.S. Pat. No. 4,331,647.
  • More selective linkage can be achieved by using a heterobifunctional linker such as maleimidehydroxysuccinimide ester. Reaction of the ester with an antibody or fragment will derivatize amine groups on the antibody or fragment, and the derivative can then be reacted with, e.g., an antibody Fab fragment having free sulfhydryl groups (or, a larger fragment or intact antibody with sulfhydryl groups appended thereto by, e.g., Tram's Reagent). Such a linker is less likely to crosslink groups in the same antibody and improves the selectivity of the linkage.
  • a heterobifunctional linker such as maleimidehydroxysuccinimide ester.
  • ScFvs with linkers greater than 12 amino acid residues in length allow interactions between the VH and VL domains on the same chain and generally form a mixture of monomers, dimers (termed diabodies) and small amounts of higher mass multi ers, (Kortt et al., Eur J Biochem. (1994) 221 : 1 1 - 157). ScFvs with linkers of 5 or less amino acid residues, however, prohibit intramolecular pairing of the VH and VL domains on the same chain, forcing pairing with VH and VL domains on a different chain.
  • Linkers between 3- and 12-residues form predominantly dimers (Atwell et al., Protein Engineering ( 1999) 12: 597-604). With linkers between 0 and 2 residues, trimeric (termed triabodies), tetrameric (termed tetrabodies) or higher oligomeric structures of scFvs are formed; however, the exact patterns of oligomerization appear to depend on the composition as well as the orientation of the V-domains, in addition to the linker length.
  • DOCK- AND -LOCKTM involves the production of fusion proteins that comprise at their N- or C-terminal ends one of two complementary peptide sequences, called dimerization and docking domain (DDD) and anchoring domain (AD) sequences.
  • the DDD sequences are derived from the regulatory subunits of cAMP-dependent protein kinase and the AD sequence is derived from the sequence of A- kinase anchoring protein (AKAP).
  • the DDD sequences form dimers that bind to the AD sequence, which allows formation of trimers, tetramers, hexamers or any of a variety of other complexes.
  • effector moieties such as antibodies or antibody fragments
  • complexes may be formed of any selected combination of antibodies or antibody fragments.
  • the DNLTM complexes may be covalently stabilized by formation of disulfide bonds or other linkages.
  • Bispecific or multispecific antibodies may be utilized in pre-targeting techniques.
  • Pre- targeting is a multistep process originally developed to resolve the slow blood clearance of directly targeting antibodies, which contributes to undesirable toxicity to normal tissues such as bone marrow.
  • a radionuclide or other therapeutic agent is attached to a small delivery molecule (targetable construct or targetable conjugate) that is cleared within minutes from the blood.
  • a pre-targeting bispecific or multispecific antibody, which has binding sites for the targetable construct as well as a target antigen, is administered first, free antibody is allowed to clear from circulation and then the targetable construct is administered.
  • a pre-targeting method of treating or diagnosing a disease or disorder in a subject may be provided by: (i) administering to the subject a bispeeific antibody or antigen binding antibody fragment; (2) optionally administering to the subject a clearing composition, and allowing the composition to clear the antibody from circulation; and (3) administering to the subject the targetable construct, containing one or more chelated or chemically bound therapeutic or diagnostic agents.
  • the technique may also be utilized for antibody dependent enzyme prodrug therapy (ADEPT) by administering an enzyme conjugated to a targetable construct, followed by a prodrug that is converted into active form by the enzyme.
  • ADPT antibody dependent enzyme prodrug therapy
  • the claimed methods and compositions may utilize any of a variety of antibodies known in the art, for example for combination antibody therapy.
  • Antibodies of use may be commercially obtained from a number of known sources. For example, a variety of antibody secreting hybridoma lines are available from the American Type Culture Collection (ATCC, Manassas, VA). A large number of antibodies against various disease targets, including but not limited to tumor-associated antigens, have been deposited at the ATCC and/or have published variable region sequences and are available for use in the claimed methods and compositions. See, e.g., U.S. Patent Nos. 7,312,318;
  • antibody sequences or antibody-secreting hybridomas against almost any disease-associated antigen may be obtained by a simple search of the A ' TCC, NCBI and/or USPTO databases for antibodies against a selected disease-associated target of interest.
  • the antigen binding domains of the cloned antibodies may be amplified, excised, ligated into an expression vector, transfected into an adapted host cell and used for protein production, using standard techniques well known in the art (see, e.g., U.S. Patent Mos. 7,531,327; 7,537,930; 7,608,425 and 7,785,880, the Examples section of each of which is incorporated herein by reference).
  • antibodies that may be of use for th erapy of cancer within the sc ope of the claimed methods and compositions include, but are not limited to, LLl (anti-CD74), LL2 or RFB4 (anti-CD22), veltuzumab (hA20, anti-CD20), rituximiab (anti-CD20), obinutuzumab (GA lOl , anti-CD20), lambrolizumab (anti-PD- 1 receptor), nivolumab (anti-PD-1 receptor), ipilimumab (anti-CTLA-4), RS7 (anti-epithelial glycoprotein- 1 (EGP-1, also known as TROP-2)), KC4 (anti-mucin), MN- 14 (anti-carcinoembryonic antigen (anti-CEA, also known as CD66e or CEACAM5), MN-15 or MN-3 (anti-CEACAM6), Mu-9 (anti-colon-specific antigen-
  • panitumumab (anti-EGFR); tositixmomab (anti-CD20); PAM4 (aka clivatuzumab, anti- MUC5AC) and trastazumah (anti-ErbB2).
  • anti-EGFR panitumumab
  • tositixmomab anti-CD20
  • PAM4 aka clivatuzumab, anti- MUC5AC
  • trastazumah anti-ErbB2
  • Patent No. 7,612,180 liMN-14 (U.S. Patent No. 6,676,924), hMN-15 (U.S. Patent No. 7,541,440), hRl (U.S. Patent Application 12/772,645), hRS7 (U.S. Patent No. 7,238,785), hMN-3 (U.S. Patent No. 7,541 ,440), AB-PG1-XG 1-026 (U.S. Patent Application 1 1/983,372, deposited as ATCC PTA-4405 and PTA-4406), D2/B (WO 2009/130575), B WA-3 (anti- histone ⁇ 4), LG2-1 (anti-histone 113) and LG2-2 (anti-histone H2B) (U.S. Patent Application Serial No. 14/180,646, filed 2/14/14) the text of each recited patent or application is incorporated herein by reference with respect to the Figures and Examples sections.
  • Other useful antigens that may be targeted using the described conjugates include carbonic anbydrase IX, B7, CCL19, CCL21, CSAp, UER-2/neu, BrE3, GDI , CD la, CD2, CD3, CD4, CDS, CDS, GDI 1 A, CD14, CD15, CD16, CD18, CD19, CD20 (e.g., C2B8, hA20, 1 F5 MAbs), CD21, CD22, CD23, CD25, CD29, CD30, CD32b, CD33, CD37, CD38, CD40, CD40L, CD44, CD45, CD46, CD47, CD52, CD54, CD55, CD59, CD64, CD67, CD70, CD74, CD79a, CD80, CD83, CD95, CD 126, CD133, CD138, CD 147, CD 154, CEACAM5, CEACAM6, CTLA-4, CXCR4, alpha-fetoprotein (AFP), VEGF (e.g
  • AVASTTNCf fibronectin splice variant
  • ED-B fibronectin e.g., LI 9
  • EGP-1 TROP-2
  • EGP-2 e.g., 17-1 A
  • EGF receptor ErbB l
  • ErbB2 ErbB3, Factor II, FHL- 1, Flt-3, folate receptor
  • CD Cluster Designation
  • the CD66 antigens consist of five different glycoproteins with similar structures, CD66a-e, encoded by the carcinoembryonic antigen (CEA) gene family members, BCG, CGM6, NCA, CGM1 and CEA, respectively. These CD66 antigens (e.g., CEACAM6) are expressed mainly in granulocytes, normal epithelial cells of the digestive tract and tumor cells of various tissues. Also included as suitable targets for cancers are cancer testis antigens, such as NY-ESO-1 (Theuriilat et al., Int. J. Cancer 2007; 120(11):241 1-7), as well as CD79a in myeloid leukemia (Kozlov et al., Cancer Genet.
  • CEACAM6 carcinoembryonic antigen
  • Macrophage migration inhibitory factor is an important regulator of innate and adaptive immunity and apoptosis. It has been reported that CD74 is the endogenous receptor for MIF (Leng et al., 2003, J Exp Med 197: 1467-76).
  • the therapeutic effect of antagonistic anti-CD74 antibodies on MlF-mediated intracellular path ways may be of use for treatment of a broad range of disease states, such as cancers of the bladder, prostate, breast, lung, colon and chronic lymphocytic leukemia (e.g., Meyer-Siegler et al., 2004, BMC Cancer 12:34; Shachar & Haran, 2011 , Leak Lymphoma 52: 1446-54); autoimmune diseases such as rheumatoid arthritis and sy stemic lupus erythematosus (Morand & Leech, 2005, Front Biosci 10: 12-22; Shachar & Haran, 201 1 , Leuk Lymphoma 52:1446-54); kidney diseases such as renal allograft rejection (Lan, 2008, Nephron Exp Nephrol.
  • a broad range of disease states such as cancers of the bladder, prostate, breast, lung, colon and chronic lymphocytic leukemia (e.g., Meyer-Siegler
  • Anti- TNF-a antibodies are known in the art and may be of use to treat immune diseases, such as autoimmune disease, immune dysfunction (e.g., graft-versus-host disease, organ transplant rejection) or diabetes.
  • Known antibodies against TNF-a include the human antibody CDP571 (Ofei et al, 201 1, Diabetes 45:881 -85); murine antibodies MTNFAI, M2TNFAI, M3T FAI, M3TNFABI, M302B and M303 (Thermo Scientific, Rockford, IL); infliximab (Centocor, Malvern, PA); certolizumab pegol (UCB, Brussels, Belgium); and adalim ' umab (Abbott, Abbott Park, IL).
  • antibodies of use for therapy of immune dysregulatory or autoimmune disease include, but are not limited to, anti-B-cell antibodies such as veltuzumab, epratuzumab, milatuzumab or hL243; tociiizumab (anti-IL-6 receptor); basiliximab (and-CD25); daclizumab (anti-CD25); efalizumab (anti-CD 11a); muromonab-CD3 (anti-CD3 receptor); anti-CD40L (UCB, Brussels, Belgium); natalizumab (anti- ⁇ x4 integrin) and omalizumab (anti-IgE).
  • anti-B-cell antibodies such as veltuzumab, epratuzumab, milatuzumab or hL243; tociiizumab (anti-IL-6 receptor); basiliximab (and-CD25); daclizumab (anti-CD25); efalizumab (
  • Immune checkpoint inhibitor antibodies have been used primarily in cancer therapy. Immune checkpoints refer to inhibitory pathways in the immune system that are responsible for maintaining self-tolerance and modulating the degree of immune system response to minimize peripheral tissue damage. However, tumor cells can also activate immune system checkpoints to decrease the effectiveness of immune response against tumor tissues.
  • Exemplary checkpoint inhibitor antibodies against cytotoxic T-lymphocyte antigen 4 (CTLA- 4, also known as CD 152), programmed cell death protein 1 (PD-1 , also known as CD279) and programmed cell death 1 ligand 1 (PD-L1, also known as CD274), may be used in combination with one or more other agents to enhance the effecti veness of immune response against disease cells, tissues or pathogens.
  • Exemplary anti-PD l antibodies include lambrolizumah (MK-3475, MERCK), nivolumab (BMS-936558, BRISTOL-MYERS SQUIBB), AMP-224 (MERCK), and pidilizumab (CT-01 1, CURETECH LTD.).
  • Anti-PDl antibodies are commercially available, for example from ABCAM® (AB 137132),
  • BIOLEGE D® ( ⁇ 2.2 ⁇ 7, RMP1 -14) and AFF YMETR1X EBIO SCIENCE (J! 05, Jl 16, MIH4).
  • Exemplary anti-PD-Ll antibodies include MDX-1105 (MEDAREX), MEDI4736 (MEDIMMUNE) MPDL3280A (GENENTECH) and BMS-936559 (BRISTOL-MYERS SQUIBB).
  • Anti-PD-Ll antibodies are also commercially available, for example from AFFYMETRIX EBIOSCIENCE (MIHl ).
  • Exemplary anti-CTLA4 antibodies include ipilimumab (Bristol-Myers Squibb) and tremelimumab (PFIZER).
  • Anti-PDl antibodies are commercially available, for example from ABCAM® (AB 134090), SINO BIOLOGICAL INC. (11 159-H03H, 1 1 159-H08H), and THERMO SCIENTIFIC PIERCE (PA5-29572, PA5- 23967, PA5-26465, MAl-12205, MA1-35914). Ipilimumab has recently received FDA approval for treatment of metastatic melanoma (Wada et al., 2013, J Transl Med 1 1 :89). More recently, other checkpoint inhibitory receptors have been identified, including TIM-3 and LAG-3 (Siagg, 2013, Ther Adv Med Oncol 5: 169-81). Antibodies against TIM-3 and LAG-3 may also be used in combination with the anti-MUC5AC antibodies disclosed herein.
  • Antibodies against matrix metalloproteinases for example matrix metalloproteinase-1 (MMP-1 ), MMP-2, MMP-7, MMP-9 and MMP- 4, are also of use in combination anticancer therapies.
  • MMP-1 matrix metalloproteinase-1
  • MMP-2 matrix metalloproteinase-2
  • MMP-7 matrix metalloproteinase-7
  • MMP-9 MMP- 4
  • antibodies of use may include anti-histone antibodies and/or antigen-binding fragments thereof, such as the BWA-3 (anti-H4), LG2-1 (anti-H3) and LG2.-2 (anti-H2B) antibodies.
  • anti-histone antibodies are disclosed, for example, in U.S. Patent Application Serial No. 14/180,646, filed 2/14/14 (the Examples section of which is incorporated herein by reference).
  • antibodies are used that internalize rapidly and are then re-expressed, processed and presented on cell surfaces, enabling continual uptake and accretion of circulating conjugate by the cell.
  • CD74 antigen is highly expressed on B-cell lymphomas (including multiple myeloma) and leukemias, certain T-cell lymphomas, melanomas, colonic, lung, and renal cancers, glioblastomas, and certain other cancers (Ong et al., Immunology 9S:296-302 (1999)), A review of the use of CD 74 antibodies in cancer is contained in Stein et al., Clin Cancer Res. 2007 Sep 15;i3(l 8 Pt 2):5556s-5563s, incorporated herein by reference.
  • the diseases that are preferably treated with anti-CD 74 antibodies include, but are not limited to, non-Hodgkin's lymphoma, Hodgkin's disease, melanoma, lung, renal, colonic cancers, glioblastome multiforme, histiocytomas, myeloid leukemias, and multiple myeloma.
  • Continual expression of the CD 74 antigen for short periods of time on the surface of target cells, followed by internalization of the antigen, and re-expression of the antigen enables the targeting LLI antibody to be internalized along with any chemotherapeutic moiety it carries. This allows a high, and therapeutic, concentration of LLI -chemotherapeutic drag conjugate to be accumulated inside such cells.
  • Internalized LL 1 -chemotherapeutic drug conjugates are cycled through lysosomes and endosomes, and the chemotherapeutic moiety is released in an active form within the target cells.
  • Certain embodiments concern methods of diagnosing or treating a malignancy in a subject, comprising administering to the subject an ami-pancreatic cancer MAb, fusion protein or fragment thereof, wherein the MAb, fusion protein or fragment is bound to at least one diagnostic and/or therapeutic agent.
  • the antibody preferably binds to an epitope located within the second to fourth cysteine -rich domains of MUC5AC (amino acid residues 1575- 2052), more preferably to an epitope located in amino acid residues 1575- 1725 and 1903- 2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1575-1725 (Cys2+), most preferably, to an epitope located in Cys2
  • the cancer is a non-endocrine pancreatic cancer
  • MAbs for in vitro diagnosis. See, for example, Carlsson et al., Bio/Technology 7 (6): 567 (1989).
  • MAbs can be used to detect the presence of a tumor-associated antigen in tissue from biopsy samples.
  • MAbs also can be used to measure the amount of tumor-associated antigen in clinical fluid samples, such as blood or serum, using techniques such as radioimmunoassay, enzyme-linked immunosorbent assay, and fluorescence immunoassay. In vitro and in vivo methods of diagnosis are discussed in further detail below.
  • Conjugates of tumor-targeted MAbs and toxins can be used to selectively kill cancer cells in vivo (Spalding, Bio/Technology 9(8): 701 ( 1991 ); Goldenberg, Scientific American Science & Medicine 1(1): 64 ( 1994)).
  • therapeutic studies in experimental animal models have demonstrated the anti-tumor activity of antibodies carrying cytotoxic radionuclides. (Goldenberg et al., Cancer Res. 41 : 4354 (1981), Cheung et al., J. Nat'l Cancer Inst. 77: 739 ( 1986), and Senekowitsch et al, J. Mucl. Med. 30: 531 ( 1989)).
  • the conjugate comprises a 90 Y-labeIed hPAM4 antibody.
  • the conjugate may optionally be administered in conjunction with one or more other therapeutic agents, in a preferred embodiment, 90 Y-labeled hPAM4 is administered together with gemcitabine or 5- fiuorouracil to a patient with pancreatic cancer.
  • 9Q Y is conjugated to a DOTA chelate for attachment to hPAM4.
  • the 9t 'Y ⁇ DOTA ⁇ hPAM4 is combined with gemcitabine in fractionated doses comprising a treatment cycle, such as with repeated, lower, less-toxic doses of gemcitabine combined with lower, fractionated doses of 90 Y-DOTA-hPAM4.
  • a radiolabeled or other conjugated PAM4 antibody may be administered in combination with another
  • immunoconjugate such as an SN-38 conjugated antibody.
  • a particularly preferred combination is u Y-hPAM4 and SN-38-hRS7 (anti-TROP2 antibody) (see, e.g., U.S. Patent No. 8,586,050, the Examples section incorporated herein by reference).
  • Chimeric, humanized and human antibodies and fragments thereof have been used for in vivo therapeutic and diagnostic methods. Accordingly contemplated is a method of delivering a diagnostic or therapeutic agent, or a combination thereof, to a target comprising (i) providing a composition that comprises an anti-pancreatic cancer antibody or fragment thereof, such as a chimeric, humanized or human PAM4 antibody, conjugated to at least one diagnostic and/or therapeutic agent and (ii) administering to a subject the diagnostic or therapeutic antibody conjugate.
  • the anti-pancreatic cancer antibodies and fragments thereof are humanized or fully human.
  • Another embodiment concerns a method for treating a malignancy comprising administering a naked or conjugated anti-pancreatic cancer antibody, antibody fragment or fusion protein that binds to an epitope located within the second to fourth cysteine-rich domains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575- 1725 and 1903-2052 (Cys2 and Cys 4), even more preferably to an epitope located in amino acid residues 1 75- 1 725 (Cys2+), most preferably, to an epitope located in Cys2, such as a PAM4 antibody, either alone or in conjunction with one or more other therapeutic agents.
  • a naked or conjugated anti-pancreatic cancer antibody, antibody fragment or fusion protein that binds to an epitope located within the second to fourth cysteine-rich domains of MUC5AC (amino acid residues 1575-2052), more preferably to an epitope located in amino acid residues 1575- 1725
  • the other therapeutic agent may be added before, simultaneously with or after the antibody.
  • the therapeutic agent is gemcitabine, and in a more preferred embodiment, gemcitabine is given w th the hPAM4 radioconjugate in a fractionated dose schedule at lower doses than the conventional 800- 1,000 mg/ ⁇ doses of gemcitabine given weekly for 6 weeks.
  • gemcitabine is given w th the hPAM4 radioconjugate in a fractionated dose schedule at lower doses than the conventional 800- 1,000 mg/ ⁇ doses of gemcitabine given weekly for 6 weeks.
  • fractionated therapeutic doses of W Y-PAM4 repeated fractionated doses intended to function as a radiosensitizing agent of 200-380 mg/m ' gemcitabine are infused.
  • the antibodies, fusion proteins and/or fragments thereof described and claimed herein may be administered with any known or described therapeutic agent, including but not limited to heat shock protein 90 (Hsp90).
  • Hsp90 heat shock protein 90
  • cyclophosphamide 200-400 mg/m * etoposide, and 150-200 mg/ ' m 7' carmustine
  • a regimen used to treat non-Hodgkin's lymphoma Patti et at, Eur. J. Haematol. 51: 18 (1993).
  • Other suitable combination chemotherapeutic regimens are well-known to those of skill in the art. See, for example, Freedman et at, "Non-Hodgkin's Lymphomas," in CANCER MEDICINE, VOLUME 2, 3rd Edition, Holland et at (eds.), pages 2028-2068 (Lea & Febiger 1993).
  • first generation chemotherapeutic regimens for treatment of intermediate- grade non-Hodgkin's lymphoma include C-MOPP (cyclophosphamide, vincristine, procarbazine and prednisone) and CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone).
  • a useful second generation chemotherapeutic regimen is m-BACOD
  • a suitable third generation regimen is MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, bleomycin and leucovorin).
  • Additional useful drugs include phenyl butyrate, bendamustme, and bryostatin-1.
  • the present invention contemplates the administration of anti-pancreatic cancer antibodies and fragments thereof, including fusion proteins and fragments thereof, alone, as a naked antibody or antibody fragment, or administered as a multimodal therapy.
  • the antibody is a humanized or fully human P.AM4 antibody or fragment thereof.
  • Multimodal therapies further include immunotherapy with a naked anti-pancreatic cancer antibody supplemented with administration of other antibodies in the form of naked antibodies, fusion proteins, or as immunoconjugates.
  • a humanized or fully human PAM4 antibody may be combined with another naked antibody, or a humanized PAM4 or other antibody conjugated to an isotope, one or more chemotherapeutic agents, cytokines, toxins or a combination thereof.
  • the present invention contemplates treatment of a naked or conjugated PAM4 antibody or fragments thereof before, in combination with, or after other pancreatic tumor associated antibodies such as CA19.9, DUPAN2, SPAN!, Nd2, B72.3, CC49, anti-Le a antibodies, and antibodies to other Lewis antigens (e.g., Le(y)), as well as antibodies against carcinoembryonic antigen (CEA or CEACAM5), CEACAM6, colon- specific antigen-p (CSAp), MUC1, MUC2, MUC3, MUC4, MUC5A.C, MLIC16, MUC17, HLA-DR, CD40, CD74, CD138, HER2/neu, EGFR, EGP-1, EGP-2, angiogenesis factors (e.g., VEGF, P1GF), insulin-like growth factor (IGF), tenascin, platelet-derived growth factor, and IL-6, as well as products of oncogenes (e.g., bcl-2,
  • These solid tumor antibodies may be naked or conjugated to, inter alia, drugs, toxins, isotopes, radionuclides or immuno modulators. Many different antibody combinations may be constructed and used in either naked or conjugated form. Alternatively, different naked antibody combinations may be employed for administration in combination with other therapeutic agents, such as a cytotoxic drug or with radiation, given consecutively, simultaneously, or sequentially.
  • Administration of the antibodies and their fragments can be effected by intravenous, intraarterial, intraperitoneal, intramuscular, subcutaneous, intrapleural, intrathecal, perfusion through a regional catheter, or direct intraiesional injection.
  • the administration may be by continuous infusion or by single or multiple boluses.
  • the immunoconjugate of the present invention can be formulated for intravenous administration via, for example, bolus injection or continuous infusion.
  • the antibody of the present invention is infused over a period of less than about 4 hours, and more preferably, over a period of less than about 3 hours.
  • the first 25-50 mg could be infused within 30 minutes, preferably even 1 min, and the remainder infused over the next 2-3 hrs.
  • Formulations for injection can be presented in unit dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative.
  • compositions can take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and can contain formulatory agents such as suspending, stabilizing and/or dispersing agents.
  • the active ingredient can be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use.
  • Control release preparations can be prepared through the use of polymers to complex or adsorb the immunoconjugate.
  • biocompatible polymers include matrices of poly(ethylene-co-vinyl acetate) and matrices of a polyanhydride copolymer of a stearic acid dimer and sebacic acid. Sherwood et al, Bio/Technology 10: 1446 (1992). The rate of release of an immunoconjugate or antibody from such a matrix depends upon the molecular weight of the immunoconjugate or antibody, the amount of immunoconjugate or antibody within the matrix, and the size of dispersed particles. Saltzman et al., Biophys. J. 55: 163 ( 1989); Sherwood et al, supra. Other solid dosage forms are described in Ansel et al., PHARMACEUTICAL DOSAGE FORMS AND DRUG
  • the dosage of an administered immunoconjugate for humans will vary depending upon such factors as the patient's age, weight, height, sex, general medical condition and previous medical history. It may be desirable to provide the recipient with a dosage of immunoconjugate, antibody fusion protein that is in the range of from about i mg/kg to 25 mg/kg as a single intravenous infusion, although a lower or higher dosage also may be administered as circumstances dictate.
  • the dosage may be repeated as needed, for example, once per week for 4-10 weeks, once per week for 8 weeks, or once per week for 4 weeks. It may also be given less frequently, such as every other week for several months, or monthly or quarterly for many months, as needed in a maintenance therapy.
  • an antibody may be administered as one dosage every 2. or 3 weeks, repeated for a total of at least 3 dosages.
  • the antibodies may be administered twice per week for 4-6 weeks. If the dosage is lowered to approximately 200-300 mg/m (340 mg per dosage for a 1.7-m patient, or 4.9 mg/kg for a 70 kg patient), it may be administered once or even twice weekly for 4 to 1 weeks.
  • the dosage schedule may be decreased, namely every 2 or 3 weeks for 2-3 months. It has been determined, however, that even higher doses, such as 2.0 mg/kg once weekly or once every 2.-3 weeks can be administered by slow i.y. infusion, for repeated dosing cycles.
  • the dosing schedule can optionally be repeated at other intervals and dosage may be given through various parenteral routes, with appropriate adjustment of the dose and schedule.
  • Anti-pancreatic cancer antibodies and fragments thereof may be conjugated to at least one therapeutic and/or diagnostic agent for therapy or diagnosis.
  • the objective is to deliver cytotoxic doses of radioactivity, toxin, antibody and/or drug to target ceils, while minimizing exposure to non-target tissues.
  • anti-pancreatic cancer antibodies are used to diagnose and/or treat pancreatic tumors.
  • any of the antibodies, antibody fragments and fusion proteins can be conjugated with one or more therapeutic or diagnostic agents, using a variety of techniques known in the art.
  • One or more therapeutic or diagnostic agents may be attached to each antibody, antibody fragment or fusion protein, for example by conjugating an agent to a carbohydrate moiety in the Fc region of the antibody. If the Fc region is absent (for example with certain antibody fragments), it is possible to introduce a carbohydrate moiety into the light chain variable region of either an antibody or antibody fragment to which a therapeutic or diagnostic agent may be attached. See, for example, Leung et al., J Immunol. 154: 5919 (1995); Hansen et al., U.S. Pat. No. 5,443,953 ( 1995), Leung et al., U.S. Pat. No. 6,254,868, the Examples section of each patent incorporated herein b reference.
  • Antibody fusion proteins or multispecific antibodies comprise two or more antibodies or fragments thereof, each of which may be attached to at least one therapeutic agent and/or diagnostic agent. Accordingly, one or more of the antibodies or fragments thereof of the antibody fusion protein can have more than one therapeutic and/or diagnostic agent attached. Further, the therapeutic agents do not need to be the same but can be different therapeutic agents, for example, one can attach a drag and a radioisotope to the same fusion protein. For example, an IgG can be radiolabeled with !ji I and attached to a drag. The Bl I can be incorporated into the tyrosine of the IgG and the drug attached to the epsilon amino group of the IgG lysines.
  • Both therapeutic and diagnostic agents also can be attached to reduced SH groups and to the carbohydrate side chains of antibodies.
  • a bispecific antibody may comprise one antibody or fragment thereof against a disease antigen and another against a hapten attached to a targetable construct, for use in pretargeting techniques as discussed above.
  • a therapeutic or diagnostic agent can be attached at the hinge region of a reduced antibody component via disulfide bond formation.
  • such agents can be attached to the antibody component using a heter obi functional cross-linker, such as N- succinyl 3-(2-pyndyldithio)proprionate (SPDP). Yu et al., Int. J. Cancer 56: 244 ( 1994). General techniques for such conjugation are well-known in the art.
  • the azide alkyne Huisgen cycloaddition reaction uses a copper catalyst in the presence of a reducing agent to catalyze the reaction of a terminal alkyne group attached to a first molecule.
  • a second molecule comprising an azide moiety
  • the azide reacts with the activated alkyne to form a 1,4-disubstituted 1,2,3-triazole.
  • the copper catalyzed reaction occurs at room temperature and is sufficiently specific that purification of the reaction product is often not required.
  • a copper- free click reaction has been proposed for covalent modification of biomolecules.
  • the copper- free reaction uses ring strain in place of the copper cataly st to promote a [3 + 2] azide-alkyne cycloaddition reaction (Id.)
  • cyclooctyne is a 8-carbon ring structure comprising an internal alkyne bond.
  • the closed ring structure induces a substantia] bond angle deformation of the acetylene, which is highly reactive with azide groups to form a triazole.
  • cyclooctyne derivatives may be used for copper-free click reactions (Id.) [0190] Another type of copper- free click reaction was reported by Ning et al . (2010, Angew Chem Int Ed 49:3065-68), involving strain-promoted alkyne-nitrone cycloaddition.
  • a wide variety of therapeutic reagents can be administered concurrently or sequentially, or advantageously conjugated to the antibodies of the invention, for example, dmgs, toxins, oligonucleotides (e.g., siRNA), imniunomodulators, hormones, hormone antagonists, enzymes, enzyme inhibitors, radionuclides, a giogenesis inhibitors, pro- apoptotic agents, etc.
  • the therapeutic agents recited here are those agents that are useful for either conjugated to an antibody, fragment or fusion protein or for administration separately with a naked antibody as described above.
  • Therapeutic agents include, for example, chemoiherapeutic drugs such as vinea alkaloids, anthracyclines, gemciiabine, epipodophyllotoxins, taxanes, antimetabolites, alkylating agents, antibiotics, SN-38, COX-2 inhibitors, antimitotics, anti angiogenic and apoptotie agents, particularly doxorubicin, methotrexate, taxol, CPT-1 1, camptothecans, proieosome inhibitors, mTOR inhibitors, HDAC inhibitors, tyrosine kinase inhibitors, and others from these and other classes of anticancer agents.
  • chemoiherapeutic drugs such as vinea alkaloids, anthracyclines, gemciiabine, epipodophyllotoxins, taxanes, antimetabolites, alkylating agents, antibiotics, SN-38, COX-2 inhibitors, antimitotics, anti angiogenic and apoptotie agents, particularly
  • cancer chemoiherapeutic drugs include nitrogen mustards, alkyl sulfonates, nitrosoureas, triazenes, folic acid analogs, COX-2 inhibitors, antimetabolites, pyrimidine analogs, purine analogs, platinum coordination complexes, mTOR inhibitors, tyrosine kinase inhibitors, proieosome inhibitors, HDAC inhibitors, camptothecins and hormones.
  • Suitable chemoiherapeutic agents are described in REMINGTON'S
  • Specific drugs of use may include 5-fluorouracil, afatmib, aplidin, azaribine, anastrozole, anthracyclines, axitinib, AVL- 101 , AVL-291, bendamusiine, bleomycin, bortezomib, hosulinib, bryostalin-1, busulfan, calicheamycin, camptothecin, carboplatin, 10- hydroxycamptothecin, carmustine, Celebrex, chlorambucil, cisplatin (CDDP), Cox-2 inhibitors, irinotecan (CPT-11), SN-38, carboplatin, cladribine, camptothecans, crizotinib, cyclophosphamide, cylarabine, dacarbazine, dasatinib, dinaciclib, docetaxel, dactinomycin, daunorubicin, doxorubicin
  • conjugates of camptothecins and related compounds may be conjugated to hPAM4 or other anti-pancreatic cancer antibodies, for example as disclosed in U.S. Patent No. 7,591,994; and U.S. Patent Application Serial No. 1 1/388,032, filed March 23, 2006, the Examples section of each of which is incorporated herein by reference.
  • prodrug forms of 2-PDQX as disclosed in U.S. Patent Application Serial No. 14/175,089 (the Examples section of which is incorporated herein by reference) may be used as an immunoeonjugate with an anti-pancreatic cancer antibody that binds to an epitope of MUC5AC as discussed above.
  • an hPAM4 antibody is given with gemcitabine, which may be given before, after, or concurrently with a naked or conjugated chimeric, humanized or human PAM4 antibody.
  • the conjugated hPAM4 antibody or antibody fragment is conjugated to a radionuclide.
  • a toxin can be of animal, plant or microbial origin.
  • a toxin, such as Pseudomonas exotoxin, may also be complexed to or form the therapeutic agent portion of an
  • toxins suitably employed in the preparation of such conjugates or other fusion proteins, include ricin, abrin, ribonuclease (RNase), DNase I, Staphylococcal enterotoxin- A, pokeweed antiviral protein, gelonin, diphtheria toxin, ranpirnase, Pseudomonas exotoxin, and Pseudomonas endotoxin.
  • An immunomodulator such as a cytokine
  • a cytokine may also be conjugated to, or form the therapeutic agent portion of the immunoeonjugate, or may be administered with, but unconjugated to, an antibody, antibody fragment or fusion protein.
  • the fusion protein may comprise one or more antibodies or fragments thereof binding to different antigens.
  • the fusion protein may bind to an epitope of MUC5AC as discussed above as well as to immunomodulating cells or factors.
  • subjects can receive a naked antibody, antibody fragment or fusion protein and a separately administered cytokine, which can be administered before, concurrently or after administration of the naked antibodies.
  • the term "immunomodulator” includes a cytokine, a lymphokine, a monokine, a stem cell growth factor, a lymphotoxin, a hematopoietic factor, a colony stimulating factor (C8F), an interferon (IF ), parathyroid hormone, thyroxine, insulin, proinsulin, relaxin, prorelaxin, follicle stimulating hormone (FSH), thyroid stimulating hormone (TSH), luteinizing hormone (LH), hepatic growth factor, prostaglandin, fibroblast growth factor, prolactin, placental lactogen, OB protein, a transforming growth factor (TGF), TGF-a, TGF- ⁇ , insulin-like growth factor (IGF), erythropoietin, thrombopoietin, tumor necrosis iactor (TNF), TNF- a, TNF- ⁇ , a mullerian-inhi biting substance, mouse go
  • the therapeutic agent may comprise one or more radioactive isotopes useful for treating diseased tissue.
  • Particularly useful therapeutic radionuclides include, but are not limited to i n In, i77 Lu, 2i2 Bi, 2 i3 Bi, 2 i i At, 6 Cix, 64 Cu, 67 Cu, 90 Y, i25 I, i 31 1, 2 P, 33 P, 4? Sc, m Ag, 67 Ga, i 42 Pr, !53 Sm, ! 6! Tb, ! 66 Dy, i66 Ho, i 86 Re, ! 88 Re, !
  • the therapeutic radionuclide preferably has a decay energy in the range of 20 to 6,000 keV, preferably in the ranges 60 to 200 keV for an Auger emitter, i 00-2,500 keV for a beta emitter, and 4,000-6,000 keV for an alpha emitter.
  • Maximum decay energies of useful beta- particle-emitting nuclides are preferably 20-5,000 keV, more preferably 100-4,000 keV, and most preferably 500-2,500 keV. Also preferred are radionuclides that substantially decay with Auger-emitting particles. For example, Co-58, Ga-67, Br-80m, Tc-99m, Rh- 103m, Pt- 109, In- 1 1 1 , Sb- 1 19, 1-125, Ho-161 , Os- 189m and lr- 192. Decay energies of useful beta- particle-emitting nuclides are preferably ⁇ 1,000 keV, more preferably ⁇ 100 keV, and most preferably ⁇ 70 keV.
  • radionuclides that substantially decay with generation of alpha-particles.
  • Such radionuclides include, but are not limited to: Dy-152, At-21 1 , Bi- 212, Ra-223, Rn-219, Po-215, Bi-21 1. Ac-225. Fr-221, At-217, Bi-213, Th-227 and Fm-255. Decay energies of useful alpha-particle-emitting radionuclides are preferably 2,000-10,000 keV, more preferably 3,000-8,000 keV, and most preferably 4,000-7,000 keV.
  • 6 'Cu considered one of the more promising radioisotopes for radioimmunotherapy due to its 61.5-hour half-life and abundant supply of beta parucles and gamma rays
  • TETA p-bromoacetamido- benzyl-tetraethylaminetetraacetic acid
  • v0 Y which emits an energetic beta particle, can be coupled to an antibody, antibody fragment or fusion protein, using diethylenetriaminepentaacetic acid (DTP A), or more preferably using DOTA.
  • DTP A diethylenetriaminepentaacetic acid
  • Additional potential therapeutic radioisotopes include ! i C, ! ' , l5 0, ' 5 Br, !9S Au,
  • a radiosensitizer can be used in combination with a naked or conjugated antibody or antibody fragment.
  • the radiosensitizer can be used in combination with a radiolabeled antibody or antibody fragment.
  • the addition of the radiosensitizer can result in enhanced efficacy when compared to treatment with the radiolabeled antibody or antibody fragment alone. Radiosensitizers are described in D. M. Goldenberg (ed.), CANCER THERAPY WITH RADIOLABELED ANTIBODIES, CRC Press (1995).
  • radionsensitizers of interest for use with this technology include gemcitabine, 5-fluorouracil, and cisplatin, and have been used in combination with extenial irradiation in the therapy of diverse cancers, including pancreatic cancer. Therefore, we have studied the combination of gemcitabine at what is believed to be radiosensitizing doses (once weekly 200 mg/m 2 over 4 weeks) of gemcitabine combined with fractionated doses of 0 Y- hPAM4, and have observed objective evidence of pancreatic cancer reduction after a single cycle of this combination that proved to be well-tolerated (no grade 3-4 toxicities by NCI- CTC v. 3 standard),
  • Antibodies or fragments thereof that have a boron addend-loaded carrier for thermal neutron activation therapy will normally be affected in similar ways. However, it will be advantageous to wait until non-targeted immunoconjugate clears before neutron irradiation is performed. Clearance can be accelerated using an anti-idiotypic antibody that binds to the anti-pancreatic cancer antibody. See U.S. Pat. No. 4,624,846 for a description of this general principle.
  • boron addends such as carboranes, can be attached to antibodies. Carboranes can be prepared with carboxyl functions on pendant side chains, as is well-known in the art.
  • Attachment of carboranes to a carrier can be achieved by activation of the carboxyl groups of the carboranes and condensation with amines on the carrier.
  • the intermediate conjugate is then conjugated to the antibody.
  • a boron addend is activated by thermal neutron irradiation and converted to radioactive atoms which decay by alpha-emission to produce highly toxic, short- range effects.
  • RNAi RNA interference
  • RISC RNA-induced silencing complex
  • Types of RNAi molecules include microRNA (miRNA) and small interfering RNA (siRNA), RNAi species can bind with messenger RNA (mRNA) through complementary base-pairing and inhibits gene expression by post- transcriptional gene silencing.
  • RNAi Upon binding to a complementary mRNA species, RNAi induces cleavage of the mRNA molecule by the argonaute component of RISC.
  • miRN A and siRNA differ in the degree of specificity for particular gene targets, with siRNA being relatively specific for a particular target gene and miRNA inhibiting translation of multiple mRNA species.
  • RNAi by inhibition of selected gene expression has been attempted for a variety of disease states, such as macular degeneration and respiratory syncytial virus infection (Sah, 2006, Life Sci 79: 1773-80). It has been suggested that siRNA functions in host cell defenses against viral infection and siRNA has been widely examined as an approach to anti-viral therapy (see, e.g., Zhang et al., 2004, Nature Med 1 1 :56-62; Novina et al., 2002, Nature Med 8:681 -86; Palliser et al., 2006, Nature 439:89-94). The use of siRNA for cancer therapy has also been attempted. Fujii et al.
  • siRNA or interference RNA species may be attached to the subject antibodies.
  • siRNA and RNAi species against a wide variety of targets are known in the art, and any such known oligonucleotide species may be utilized in the claimed methods and compositions.
  • siRNA species of potential use include those specific for IKK-gamma (U.S. Patent 7,022,828); VEGF, Flt-1 and Flk-l/KDR (U.S. Patent 7, 148,342); Bcl2 and EGFR (U.S. Patent 7,541 ,453); CDC20 (U.S. Patent 7,550,572); transducin (beta)-like 3 (U.S. Patent 7,576,196); KRAS (U.S. Patent 7,576,197); carbonic anhydrase II (U.S. Patent 7,579,457); complement component 3 (U.S.
  • Patent 7,582,746 interleukin- 1 receptor- associated kinase 4 (IRAK4) (U.S. Patent 7,592,443); survivin (U.S. Patent 7,608,7070); superoxide dismutase 1 (U.S. Patent 7,632,938); MET proto-oncogene (U.S. Patent
  • amyloid beta precursor protein U.S. Patent 7,635,771
  • IGF-1R U.S. Patent 7,638,621
  • ICAMl U.S. Patent 7,642,349
  • complement factor B U.S. Patent 7,696,344
  • p53 7,781 ,575)
  • apolipoprotein B 7,795,421
  • siRNA species are available from known commercial sources, such as Sigma-Aldrich (St Louis, MO), Invitrogen (Carlsbad, CA), Santa Cruz Biotechnology (Santa Cruz, CA), Ambion (Austin, TX), Dhannacon (Thermo Scientific, Lafayette, CO), Promega (Madison, WI), Minis Bio (Madison, WI) and Qiagen (Valencia, CA), among many others.
  • Other publicly available sources of siRNA species include the siRNAdb database at the Swedish Bioinformatics Centre, the MIT/ICBP siRNA Database, the RNAi Consortium shRNA Library at the Broad Institute, and the Probe database at NCBI.
  • siRNA species there are 30,852 siRNA species in the NCBI Probe database.
  • the skilled artisan will realize thai for any gene of interest, either an siRNA species has already been designed, or one may readily be designed using publicly available software tools. Any such siRNA species may be delivered using the subject DNLTM complexes.
  • siRNA species that have been reported are listed in Table i. Although siRNA is delivered as a double-stranded molecule, for simplicity only the sense strand sequences are shown in Table 1.
  • VEGF R2 AATGCGGCGGTGGTGACAGTA SEQ ID NO: 2 VEGF R2 AAGCTCAGCACACAGAAAGAC SEQ ID NO:23 CXCR4 UAAAAUCUUCCUGCCCACCdTdT SEQ ID NO:24 CXCR4 GGAAGC UGUU GGCUGAAAAdTd ' T SEQ ID NO:25 PPARC1 AAGACCAGCCUCUUUGCCCAG SEQ ID NO:26 Dynamin 2 GGACCAGGCAGAAAACGAG SEQ ID NO:27 Catenin CUAUCAGGAUGACGCGG SEQ ID NO:28
  • Sortilin I AGGTGGTGTTAACAGCAGAG SEQ ID NO:32 Apolipoprotein E AAGGTGGAGCAAGCGGTGGAG SEQ ID O:33 Apolipoprotein E A AGG AGTTG AA GGCCG ACA A A SEQ ID NO:. -.4 Bcl-X UAUGGAGCUGCAGAGGAUGdTdT SEQ ID NO:35 Raf- 1 TTTGAATATCTGTGCTGAGAACACA SEQ ID NO:36
  • IGFBP3 AAUCAUCAUCAAGAAAGGGCA SEQ ID NO:38 Thioredoxin AUGACUGlJCAGGAlJGUIJGCdTdT SEQ ID NO:39 CD44 GAACGAAUCCUGAAGACAUCU SEQ ID NO:40 MMP14 AAGCCTG GCT AC AGC AATATGCCTGTCTC SEQ ID NO:41
  • CEACAM1 AACCTTCTGGAACCCGCCCAC SEQ ID NO:47
  • diagnosis In the context of this application, the terms “diagnosis” or “detection” can be used interchangeably. Whereas diagnosis usually refers to defining a tissue's specific histological status, detection recognizes and locates a tissue, lesion or organism containing a particular antigen.
  • the subject antibodies and fragments can be detectably labeled by linking the antibody to an enzyme.
  • the enzyme moiety reacts with the substrate to produce a chemical moiety which can be detected, for example, by spectrophotometrie s iluorometric or visual means.
  • enzymes that can be used to detectably label antibody include malate dehydrogenase, staphylococcal nuclease, delta-V-steroid isomerase, yeast alcohol dehydrogenase, alpha-glycerophosphaie dehydrogenase, triose phosphate isomerase, horseradish peroxidase, alkaline phosphatase, asparaginase, glucose oxidase, alpha- galactosidase, ribonuclease, urease, catalase, glucosc-6-phosphate dehydrogenase, glucoamylase and acetylcholinesterase.
  • the immunoconjugate may comprise one or more radioactive isotopes useful for detecting diseased tissue.
  • Particularly useful diagnostic radionuclides include, but are not limited to, n o In, l u In, ! 77 Lu, , 8 F, 52 Fe, 6 Cu, 64 Cu, 67 Cu, 67 Ga, Ga, 86 Y, 90 Y, 9 Zr, Wm Tc, 94 Tc, 99m Tc, i20 I, i23 I, % i2 % 1 I, i54' - i5S Gd, 32 P, 1 ! C, i3 N, 15 0, 186 Re, 188 Re, 5 !
  • positron-emitters preferably with a decay energy in the range of 20 to 4,000 keV, more preferably in the range of 25 to 4,000 keV, and even more preferably in the range of 25 to 1 ,000 keV, and still more preferably in the range of 70 to 700 keV.
  • Total decay energies of useful positron-emitting radionuclides are preferably ⁇ 2,000 keV, more preferably under 1,000 keV, and most preferably ⁇ 700 keV.
  • Radionuclides useful as diagnostic agents utilizing gamma-ray detection include, but are not limited to: 5l Cr, 5 ? Co, 38 Co, 59 Fe, 6? Cu, °'Ga, ?5 Se, 9 'Ru, m Te, 11 'in, i i4m In, 12 I, 125 I, 13i I, i69 Yb, 197 Hg, and 201 T1. Decay energies of useful gamma-ray emitting radionuclides are preferably 20-2000 keV, more preferably 60-600 keV, and most preferably 100-300 keV.
  • Methods of diagnosing cancer in a subject may be accomplished by administering a diagnostic immunoconjugate and detecting the diagnostic label attached to an
  • a suitable non-radioactive diagnostic agent is a contrast agent suitable for magnetic resonance imaging, X-rays, computed tomography or ultrasound.
  • Magnetic imaging agents include, for example, nonradioactive metals, such as manganese, iron and gadolinium, complexed with metal-chelate combinations that include 2-benzyl-DTPA and its monomethyl and cyclohexyl analogs. See U.S. Ser. No. 09/921 ,290 (now abandoned) filed on Oct. 10, 2001 , the Examples section of which is incorporated herein by reference.
  • Other imaging agents such as PET scanning nucleotides, preierably l8 F, may also be used.
  • Contrast agents such as MR1 contrast agents, including, for example, gadolinium ions, lanthanum ions, dysprosium ions, iron ions, manganese ions or other comparable labels, CT contrast agents, and ultrasound contrast agents may be used as diagnostic agents.
  • Paramagnetic ions suitable for use include chromium (111), manganese (II), iron (III ), iron
  • gadolinium is particularly preferred.
  • Ions useful in other contexts include but are not limited to lanthanum (III), gold (III), lead (II) and bismuth (III).
  • Fluorescent labels include rhodamine, fluorescein and renographin. Rhodamine and fluorescein are often linked via an isothiocyanate intermediate.
  • Metals are also useful in diagnostic agents, including those for magnetic resonance imaging techniques. These metals include, but are not limited to: gadolinium, manganese, iron, chromium, copper, cobalt, nickel, dysprosium, rhenium, europium, terbium, holmium and neodymium.
  • a reagent having a long tail to which are attached a multiplicity of chelating groups for binding the ions.
  • a tail can be a polymer such as a polylysine.
  • polysaccharide or other derivatized or derivatizable chain having pendant groups to which can be bound chelating groups such as, e.g., ethylenediamineteiraacetic acid EDTA), diethylenetriaminepentaaeetic acid (DTPA), porphyrins, polyamines, crown ethers, bis-thiosemicarbazones, polyoximes, and like groups known to be useful for this purpose.
  • chelating groups such as, e.g., ethylenediamineteiraacetic acid EDTA), diethylenetriaminepentaaeetic acid (DTPA), porphyrins, polyamines, crown ethers, bis-thiosemicarbazones, polyoximes, and like groups known to be useful for this purpose.
  • Chelates are coupled to an antibody, fusion protein, or fragments thereof using standard chemistries.
  • the chelate is normally linked to the antibody by a group which enables formation of a bond to the molecule with minimal loss of immunoreactiyity and minimal aggregation and/or internal cross-linking.
  • Other, more unusual, methods and reagents for conjugating chelates to antibodies are disclosed in U.S. Pat. No. 4,824,659 to Hawthorne, entitled “Antibody Conjugates", issued Apr. 25, 1989, the Examples section of which is incorporated herein by reference.
  • Particularly useful meiai-chelate combinations include 2- benzyl-DTPA and its monomethyl and cyclohexyl analogs, used with diagnostic isotopes in the general energy range of 20 to 2,000 keV.
  • the same chelates, when complexed with nonradioactive metals, such as manganese, iron and gadolinium are useful for MRI.
  • Macrocyclic chelates such as NOT A, DOTA, and TETA are of use with a variety of metals and radiometals, most particularly with radionuclides of gallium, yttrium and copper, respectively.
  • Such metal-chelate complexes can be made very stable by tailoring the ring size to the metal of interest.
  • Other ring-type chelates such as macrocyclic polyethers, which are of interest for stably binding nuclides, such as 223Ra for RAIT are encompassed by the invention.
  • Radiopaque and contrast materials are used for enhancing X-rays and computed tomography, and include iodine compounds, barium compounds, gallium compounds, thallium compounds, etc. Specific compounds include barium, diatrizoate, ethiodized oil, gallium citrate, iocarmic acid, iocetamic acid, iodamide, iodipamide, iodoxamic acid, iogulamide, iohexoi, iopamidoi, iopanoic acid, ioprocemic acid, iosefamic acid, ioseric acid, iosulamide meglumine, iosemetic acid, iotasul, iotetric acid, iothalamic acid, totroxic acid, ioxaglic acid, ioxotrizoic acid, ipodate, meglumine, metrizamide, metrizo
  • the antibodies, antibody fragments and fusion proteins also can be labeled with a fluorescent compound.
  • the presence of a fluorescent-labeled MAb is determined by exposing the antibody to light of the proper wavelength and detecting the resultant fluorescence.
  • Fluorescent labeling compounds include Alexa 350, Alexa 430, AMCA, aminoacridine, BODIPY 630/650, BODIPY 650/665, RODIPY-FL, BODIPY-R.6G, BODIPY-TMR,
  • BODIPY-TRX 5-carboxy-4',5'-dichloro-2 ⁇ 7'-dimethoxy fluorescein, 5-carboxy-2',4',5',7'- teirachlorofluorescein, 5-carboxyfluorescein, 5-carboxyrhodamine, 6-carboxyrhodamine, 6- carboxytetramethyl amino, Cascade Blue, Cy2, Cy3, Cy5,6-FAM, dansyl chloride.
  • Fluorescently-labeled antibodies are particularly useful for flow cytometry analysis, but can also be used in endoscopic and intravascular detection methods.
  • the antibodies, antibody fragments and fusion proteins can be detectably labeled by coupling the antibody to a chemiluminescent compound.
  • the presence of the chemiluminescent-tagged MAb is determined by detecting the presence of luminescence that arises during the course of a chemical reaction. Examples of
  • chemiluminescent labeling compounds include iuminol, isoluminol, an aromatic acridinium ester, an imidazole, an acridinium salt and an oxalate ester.
  • a bioluminescent compound can be used to label the antibodies and fragments there.
  • Bioluminescence is a type of chemiluminescence found in biological systems in which a catalytic protein increases the efficiency of the chemiluminescent reaction. The presence of a bioluminescent protein is determined by detecting the presence of luminescence.
  • Bioluminescent compounds thai are useful for labeling include luciferin, iuciferase and aequorin.
  • a method of diagnosing a malignancy in a subject comprising performing an in vitro diagnosis assay on a specimen (fluid, tissue or cells) from the subject with a composition comprising an anti-pancreatic cancer MAb, fusion protein or fragment thereof, Immunohistochemistry can be used to detect the presence of PAM4 antigen in a ceil or tissue by the presence of bound antibody.
  • the malignancy that is being diagnosed is a cancer.
  • the cancer is pancreatic cancer.
  • a chelator such as DTPA, DOTA, TETA, or NOTA or a suitable peptide, to which a detectable label, such as a fluorescent molecule, or cytotoxic agent, such as a heavy metal or radionuclide, can be conjugated to a subject antibody.
  • a therapeutically useful immunoconj ugate can be obtained by conjugating a photoactive agent or dye to an antibody fusion protein.
  • Fluorescent compositions, such as fluorochrome, and other chromogens, or dyes, such as porphyrins sensitive to visible light have been used to detect and to treat lesions by directing the suitable light to the lesion. In therapy, this has been termed photoradiation, phototherapy, or photodynamic therapy (Jori et al. (eds.),
  • Fluorescent and radioactive agents conjugated to antibodies or used in bispecific, pretargeting methods are particularly useful for endoscopic, intraoperative or intravascular detection of the targeted antigens associated with diseased tissues or clusters of cells, such as malignant tumors, as disclosed in Goldenberg U.S. Pat. Nos. 5,716,595; 6,096,289 and 6,387,350, the Examples section of each incorporated herein by reference, particularly with gamma-, beta- and positron-emitters.
  • Endoscopic applications may be used when there is spread to a structure that allows an endoscope, such as the colon.
  • Radionuclides useful for positron emission tomography include, but are not limited to: F-18, Mn-51, Mn-52m, Fe-52, Co-55, Cu-62, Cu-64, Ga-68, As-72, Br-75, Br-76, Rb-82m, Sr-83, Y-86, Zr-89, Tc-94m, In- 1 10, 1- 120, and 1-124.
  • Total decay energies of useful positron-emitting radionuclides are preferably ⁇ 2,000 keV, more preferably under 1,000 keV, and most preferably ⁇ 700 keV.
  • Radionuclides useful as diagnostic agents utilizing gamma-ray detection include, but are not limited to: Cr-51 , Co-57, Co-58, Fe-59, Cu-67, Ga-67, Se-75, Ru-97, Tc-99m, ln-111, In- 1 14m, 1-123, 1-125, 1-131, Yb- 169, Hg-197, and T ' i-201. Decay energies of useful gamma-ray emitting radionuclides are preferably 20-2000 keV, more preferably 60-600 keV, and most preferably i 00-300 keV.
  • the present invention contemplates the use of anti-pancreatic cancer antibodies to screen biological samples in vitro for the presence of the PAM4 antigen. In such
  • the antibody, antibody fragment or fusion protein may be utilized in liquid phase or bound to a solid-phase carrier, as described below.
  • a solid-phase carrier for purposes of in vitro diagnosis, any type of antibody such as murine, chimeric, humanized or human may be utilized, since there is no host immune response to consider.
  • a screening method for determining whether a biological sample contains MUC5AC is the radioimmunoassay (RIA).
  • RIA radioimmunoassay
  • the substance under test is mixed with PAM4 MAb in the presence of radiolabeled MUC5AC.
  • the concentration of the test substance will be inversely proportional to the amount of labeled MUC5AC bound to the MAb and directly related to the amount of free, labeled MUC5AC.
  • Other suitable screening methods will be readily apparent to those of skill in the art.
  • in vitro assays can be performed in which an anti-pancreatic cancer antibody, antibody fragment or fusion protein is bound to a solid-phase carrier.
  • MAbs can be attached to a polymer, such as aminodextran, in order to link the MAb to an insoluble support such as a polymer-coated bead, a plate or a tube.
  • the presence of the PAM4 antigen in a biological sample can be determined using an enzyme-linked immunosorbent assay (ELISA) (e.g., Gold et al. J Clin Oncol. 24:252-58, 2006).
  • ELISA enzyme-linked immunosorbent assay
  • a pure or semipure antigen preparation is bound to a solid support that is insoluble in the fluid or cellular extract being tested and a quantity of detectably labeled soluble antibody is added to permit detection and/or quantitation of the binary complex formed between solid-phase antigen and labeled antibody.
  • a double-determinant ELISA also known as a “two-site ELISA” or “sandwich assay”
  • the double-determinant ELISA is preferred to the direct competitive ELISA for the detection of an antigen in a clinical sample. See, for example, the use of the double-determinant ELIS A for quantitation of the c-mye oncoprotein in biopsy specimens. Field et al.. Oncogene 4: 1463 (1989); Spandidos et al, Anticancer Res. 9: 821 (1989).
  • a quantity of unlabeled MAb or antibody fragment (the "capture antibody”) is bound to a solid support, the test sample is brought into contact with the capture antibody, and a quantity of detectably labeled soluble antibody (or antibody fragment ) is added to permit detection and/or quantitation of the ternary complex formed between the capture antibody, antigen, and labeled antibody.
  • an antibody fragment is a portion of an anti-pancreatic cancer MAb that binds to an epitope of MUC5AC.
  • the soluble antibody or antibody fragment must bind to a MUC5AC epitope that is distinct from the epitope recognized by the capture antibody.
  • the double- determinant ELISA can be performed to ascertain whether the PAM4 antigen is present in a biopsy sample. Alternati ely, the assay can be performed to quantitate the amount of MUC5AC that is present in a clinical sample of body fluid.
  • the quantitative assay can be performed by including dilutions of purified MUC5AC.
  • the anti-pancreatic cancer MAbs, fusion proteins, and fragments thereof also are suited for the preparation of an assay kit.
  • a kit may comprise a carrier means that is compartmentalized to receive in close confinement one or more container means such as vials, tubes and the like, each of said container means comprising the separate elements of the immunoassay.
  • the subject antibodies, antibody fragments and fusion proteins also can be used to detect the presence of the PAM4 antigen in tissue sections prepared from a histological specimen.
  • Such in situ detection can be used to determine the presence of MUC5AC and to determine the distribution of MUC5AC in the examined tissue.
  • In situ detection can be accomplished by applying a detectably-labeled antibody to frozen tissue sections. Studies indicate that the PAM4 antigen is preserved in paraffin-embedded sections. General techniques of in situ detection are well-known to those of ordinary skill. See, for example, Ponder, "Cell Marking Techniques and Their Application," in MAMMALIAN
  • Antibodies, antibody fragme s and fusion proteins can be detectably labeled with any appropriate marker moiety, for example, a radioisotope, an enzyme, a fluorescent label, a dye, a chromogen, a chemiluminescent label, a bioluminescent labels or a paramagnetic label.
  • a marker moiety for example, a radioisotope, an enzyme, a fluorescent label, a dye, a chromogen, a chemiluminescent label, a bioluminescent labels or a paramagnetic label.
  • the marker moiety can be a radioisotope that is detected by such means as the use of a gamma counter or a scintillation counter or by autoradiography.
  • the diagnostic conjugate is a gamma-, beta- or a positron-emitting isotope.
  • a marker moiety in the present description refers to a molecule that will generate a signal under predetermined conditions. Examples of marker moieties include radioisotopes, enzymes, fluorescent labels, chemiluminescent labels, bioluminescent labels and paramagnetic labels.
  • the above-described in vitro and in situ detection methods may be used to assist in the diagnosis or staging of a pathological condition.
  • such methods can be used to detect tumors that express the PAM4 antigen such as pancreatic cancer.
  • radioisotopes may be bound to antibody either directly or indirectly by using an intermediar functional group.
  • intermediary functional groups include chelators such as ethylenediarnmetetraacetie acid and diethylenetxiaminepentaacetic acid.
  • the radiation dose delivered to the patient is maintained at as low a level as possible through the choice of isotope for the best combination of minimum half-life, minimum retention in the body, and minimum quantity of isotope which will permit detection and accurate measurement.
  • radioisotopes that can be bound to anti-pancreatic cancer antibody and are appropriate for diagnostic imaging include 99m Tc, n 'In and iS F.
  • the subject antibodies, antibody fragments and fusion proteins also can be labeled with paramagnetic ions and a variety of radiological contrast agents for purposes of in vivo diagnosis.
  • Contrast agents that are particularly useful for magnetic resonance imaging comprise gadolinium, manganese, dysprosium, lanthanum, or iron ions. Additional agents include chromium, copper, cobalt, nickel, rhenium, europium, terbium, holmium, or neodymium.
  • Antibodies and fragments thereof can also be conjugated to ultrasound contrast/enhancing agents.
  • one ultrasound contrast agent is a liposome.
  • the ultrasound contrast agent is a liposome that is gas filled.
  • a bispeeific antibody can be conjugated to a contrast agent.
  • the bispeeific antibody may comprise more than one image- enhancing agent for use in ultrasound imaging.
  • the contrast agent is a liposome.
  • the liposome comprises a bivalent DTP A -peptide covalently attached to the outside surface of the liposome.
  • Control release preparations can be prepared through the use of polymers to complex or adsorb the antibody, antibody fragment or fusion protein.
  • biocompatible polymers include matrices of poly(ethylene-co- vinyl acetate) and matrices of a polyanhydride copolymer of a stearic acid dimer and sebacic acid. Sherwood et al., Bio/Technology 10: 1446 ( 1992). The rate of release of an antibody, antibody fragment or fusion protein from such a matrix depends upon the molecular weight of the antibody, antibody fragment or fusion protein, the amount of antibody within the matrix, and the size of dispersed particles.
  • the antibodies, fragments thereof or fusion proteins to be delivered to a subject can comprise one or more pharmaceutically suitable excipients, one or more additional ingredients, or some combination of these.
  • the antibody can be formulated according to known methods to prepare pharmaceutically useful compositions, whereby the
  • a pharmaceutically suitable excipient Sterile phosphate-buffered saline is one example of a pharmaceutically suitable excipient.
  • Other suitable excipients are well-known to those in the art. See, for example, Ansel et al., PHARMACEUTICAL DOS AGE FORMS AND DRUG DELIVERY SYSTEMS, 5th Edition (Lea & Febiger 1990), and Gennaro (ed.), REMINGTON'S
  • the immunoconjugate or naked antibody can be formulated for intravenous administration via, for example, bolus injection or continuous infusion.
  • Formulations for injection can be presented in unit dosage form, e.g., in ampules or in multi-dose containers, with an added preservative.
  • the compositions can take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and can contain formulatory agents such as suspending, stabilizing and/or dispersing agents.
  • the active ingredient can be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen- ree water, before use.
  • the immunoconjugate, naked antibody, fragment thereof or fusion protein may also be administered to a mammal subeutancously or by other parenteral routes.
  • the antibody or fragment thereof is administered in a dosage of 20 to 2000 milligrams protein per dose.
  • the administration may be by continuous infusion or by single or multiple boluses.
  • the dosage of an administered immunoconjugate, fusion protein or naked antibody for humans will vary depending upon such factors as the patient's age, weight, height, sex, general medical condition and previous medical history.
  • a dosage of immunoconjugate, antibody fusion protein or naked antibody that is in the range of from about I mg/kg to 20 mg/kg as a single intravenous or infusion, although a lower or higher dosage also may be administered as circumstances dictate.
  • This dosage may be repeated as needed, for example, once per week for four to ten weeks, preferably once per week for eight weeks, and more preferably, once per week for four weeks. It may also be given less frequently, such as every other week for several months, or more frequently, such as two- or three-time weekly.
  • the dosage may be given through various parenteral routes, with appropriate adjustment of the dose and schedule.
  • kits containing components suitable for treating or diagnosing diseased tissue in a patient may contain at least one antibody, antigen binding fragment or fusion protein as described herein. If the composition containing components for administration is not formulated for delivery via the alimentary canal, such as by oral delivery, a device capable of delivering the kit components through some other route may be included.
  • a device capable of delivering the kit components through some other route may be included.
  • an anti-pancreatic cancer antibody or antigen binding fragment thereof may be provided in the form of a prefllled syringe or autoinjection pen containing a sterile, liquid formulation or lyophilized preparation of antibody (e.g., Kivitz et al confuse Clin, Ther. 2006, 28: 1619-29).
  • the kit components may be packaged together or separated into two or more containers.
  • the containers may be vials that contain sterile, lyophilized formulations of a composition that are suitable for reconstitution.
  • a kit may also contain one or more buffers suitable for reconstitution and/or dilution of other reagents.
  • Other containers that may be used include, but are not limited to, a pouch, tray, box, tube, or the like. Kit components may be packaged and maintained sterilely within the containers. Another component that can be included is instructions for use of the kit,
  • PAM4 is a murine monoclonal antibody showing high specificity for pancreatic ductal adenocarcinoma (PDAC) compared with normal tissues and other cancers.
  • PDAC pancreatic ductal adenocarcinoma
  • Humanized PAM4 labeled with 90 Y in combination with low-dose gemeitabine has shown promising therapeutic activity in patients with metastatic PDAC, and is being evaluated in a phase III registration trial.
  • Prior efforts have suggested the mucin species recognized by PAM4 is human MUC5AC, a secretory mucin expressed de novo in early pancreatic intraepithelial neoplasia and retained throughout disease progression.
  • HRP horseradish peroxidase
  • HPAM4 horseradish peroxidase conjugate
  • SureLINK HRP Conjugation Kit Karlegaard & Perry Laboratories
  • MAN-5ACI a rabbit antiserum against MUC5AC (Thornton et al., 1996, Biochem J 316:967-75) was a generous gift from Dr. David J. Thornton (University of Manchester).
  • SEPHAROSE® ® CL-2B was purchased from Sigraa-Aldrich.
  • cells were fixed in 4% formalin (Sigma- Aldrich) for 15 min at RT, and then treated with 0.1% Triton X-100 in PBS for another 15 min. After washing twice with PBS, ceils were incubated with 10 , ug/mi of either hPAM4 or a murine mAb against MUC5AC or MIJCl in PBS plus 1 % BSA for 45 min at RT. Afterwards, cells were washed twice and incubated with a mixture of FITC-GAH and Cy3-GAM in PBS plus 1% BSA for 30 min at RT. After three washes, chambers were dissembled.
  • RNA Interference - CFPAC-1 cells grown to 90% confluence were used for transfection.
  • MUC5AC SiRNA or PBS alone (Mock) was 1 : 100 diluted into Opti-MEM I Medium (Life Technologies) prior to the addition of 1/100 volume of LIPOFECTAMINE® RNAiMAX Reagent (Life Technologies). After 20 min incubation at RT, the siRNA or Mock mixture was dispersed onto 8-chamber slides (80 ⁇ /chamber). Meanwhile, cells were trypsinized, washed, diluted in complete growth medium, and then added at 8x 10 3 cells/400 ⁇ /chamber. The final RNA concentration was 15.6 nM in a total volume of 480 ⁇ . After 48- h incubation, cells were stained with hPAM4 and anti-MUC5AC mAbs and examined under fluorescence microscope as described above.
  • HRP-hPAM4 or ⁇ -MUCl was diluted in PBS and added at 100 ⁇ /well. After 1 -h incubation at RT, plates with ot-MUCl were washed and incubated further with HRP-GAM for I h. Plates were washed and bound HRP-hPAM4 or HRP-GAM was detected with o-phenylenedi mine dihydrochloride (0.4 mg/ml) in PBS plus 0.03% hydrogen peroxide as a substrate. The optical density was read at 490 nm using the En Vision 2100 Multilabel Reader (PerkinElmer).
  • the fractions eluted in the void-volume peak were also pooled, dialyzed against the PBS- AG buffer (35.2 mM Na 2 P0 4 .7H 2 0; 0.4 M NaCl; 6.5 mM NaH 2 P04.H 2 0; 150 mM arginine; 150 mM monosodium glutamate, pH 8.0), and concentrated with 30 kDa Amicon Ultra centrifugal filters (EMD Millipore) for further analysis.
  • PBS- AG buffer 35.2 mM Na 2 P0 4 .7H 2 0; 0.4 M NaCl; 6.5 mM NaH 2 P04.H 2 0; 150 mM arginine; 150 mM monosodium glutamate, pH 8.0
  • EMD Millipore Amicon Ultra centrifugal filters
  • MUC5AC Sandwich ELISA - MaxiSorp 96-well plates were coated with 100 ⁇ of 2- 1 1M1 (20 ⁇ g/ml in PBS and incubated at 4 °C overnight. After blocking with casein buffer, a 5-fold concentrated void-volume peak pooled from the CL-2B fractionation of Capan-1 supernatant (hereafter referred to as the Capan-1 void- volume peak) was 2-fold serially diluted and added to the plate at 100 ⁇ /weli. After overnight incubation at RT, plates were washed and detected by HRP-PAM4, or by Biotin-45Ml plus HRP-streptavidin as a positive control.
  • Agarose Gel Electrophoresis was performed as described (Sheehan et al., 2000, Bioehem J 347:37-44), with modifications. Briefly, the Capan-1 void- volume peak was concentrated in PBS-AG buffer and diluted with gel running buffer (40 mM Tris-acetaie/lmM EDTA, 0.1%SDS, pH 8.0). In selective experiments, serum samples from normal subjects or pancreatic cancer patients were mixed with an equal volume of 8 M guanidine hydrochloride (GdmCl) and dialyzed into gel running buffer.
  • Gel running buffer 40 mM Tris-acetaie/lmM EDTA, 0.1%SDS, pH 8.0.
  • Electrophoresis was performed at 30 V for 4 to 8 h in the Horizon 58 Electrophoresis Apparatus (LAJBRepCo),
  • Additional vectors were constructed from pSM-MUC5AC-CH-long by replacing the DNA sequence of AA3993-5030 with that of AA 1 -1217, AA1218-2199, AA 1218-1517, AA 1575-2052, AA1725-2052, AAl 575- 1723/1903-2052, AA1575-1853, and AA1575-1725, to express Dl-D2-D'-D3 (b- fragment), 1 lP15-Cysl-2-3-4-5 (c-fragment), HP15-Cysl (d-fragment), Cys2-3-4 (e- fragment), Cys3-4 (f-fragment), Cys2/4 (g-firagment), Cys2-3 (h- fragment), and Cys2+ (i- fragment), respectively, as listed in Table 2.
  • GFP-fused fragments were produced by replacing the Myc tag with a full GFP sequence in the vectors encoding Cys2-3- 4, Cys3-4, Cys2/4, and Cys2-3, resulting in the e*-, f*-, g*- and h*-fragment, respectively.
  • Myc-tagged Cys2-3-4 and Cys2+ were also expressed in E. coli, and purified from the inclusion body using HIS-Select Nickel Affinity Gel (Sigma- Aldrich), and refolded.
  • KPAM4 exclusively co-localized with MUC5AC (as identified by two anti- MUC5AC mAbs, 2-1 1 M1 and 2-12M1), but not with MUC1 or MUC17 (data not shown), suggesting that MUC5AC is the hPAM4-reactive antigen.
  • hPAM4 and 2-1 1M1 are co- localized in untreated CFPAC-1 ceils, as well as the mock-treated (transfection agent alone) cells, in contrast, treatment with MUCSAC-specific siRNA resulted in substantially reduced immunostaining for both 2- 1 1 M1 and hPAM4. Moreover, as shown in the bottom panel of FIG. 2, siRNA knockdown of MUC5AC did not alter the anti-MUCl immunostaining, providing further evidence that hPAM4 is not reactive with MUCI .
  • Presence of the hPAM4 Antigen in the Culture Supernatant of Mucin-producing Carcinoma Cell Lines - MUC5AC is a highly oligomeric secretory mucin that has been isolated from cell culture and in vivo mucous secretions (Sheehan et ai., 2000, Biochem J 347:37-44; Hovenberg et al, 1996, Giycoconj J 13:839-47).
  • Our early studies showed that hPAM4 reacts with mucin derived from the CaPan-1 xenografted human PDAC (Gold et ai, 1994, Int J Cancer 57:204-10).
  • HT-29 Sheehan et al., 2000, Biochem J 347:37-44
  • LS 174T Asker et al., 1998, Biochem J 335:381-7
  • SW1990 Hoshi et al, 201 1, int J Oncol 38:6 9- 27
  • CFPAC- 1 Liuka et al., 201 1 , J Biorned Biotechriol 201 1 :93475728
  • Calu-3 Rose et al., 2000, J Aerosol Med 13:245-61
  • Cys2-3-4 (AA1575-2052) and Cys2+ (AA1575-1725) in E. coli, as evidenced by the coomassie blue staining (FIG. 6A) and Western blot using anti- Myc (FIG. 6B), was instrumental in further defining the location of the hPAM4 epitope to the Cys2 subdomain.
  • the nglycosylated Cys2-3-4 and Cys2+ were isolated predominantly as monomeric species of 55.4 and 20.5 kDa, respectively.
  • hPAM4 reacts with non-reduced, but not the reduced, Cys2-3-4 and Cys2+.
  • MUC5AC could be detected as early as the pre-malignant/dysplastic stages (Nagata et al., 2007, j Hepatobiliary Pancreat Surg 14:243-54), and was identified in a high percentage of PDAC (Remmers et al., 2013, Clin Cancer Res 19:1981-93; Yamazoe et al, 201 1, Pancreas 40:896-904; Kanno et al, 2006, Pancreas 33:391-6).
  • DEG Y TFCESPR SEQ ID NO:56
  • SEQ ID NO:56 one of the 6 MUC5AC peptides most frequently detected in the pancreatic cystic lesions with malignant potential, and not in the benign lesions, is located in the Cys2 and Cys4 subdomains, as reported in a very recent study of mucin proteomics (Jabbar et al., 2014, j Nail Cancer Inst 106:djt439).
  • hPAM4 would prevail for underglycosylated MUC5AC, whose expression in epithelial cancers in general, and PDAC in particular, including the early-stage pancreatic cancer precursors, has not been as well studied as that of underglycosylated MUC1 (Reis et al., 1998, Int J Cancer 79:402-10).
  • MUCSAC-expressing cancers such as biliary tract cancer (Wongkham et al, 2003, Cancer Lett 195:93-9), colorectal cancer (Bu et al., 2010, World J Gastroenterol 16:4089-94), and gastric cancer (Wang et al., 2003, J Surg Oncol 83 :453-60), in addition to PDAC.
  • the chelate-hPAM4 conjugate (clivatiizumab tetraxetan) was labeled with 90 -yttrium ( 0 Y), a beta-emitting radionuclide with a radiation path-length of ⁇ 5 mm suitable for bulky tumors.
  • Gemcitabine is a known radioscnsitizcr (Morgan et al, 2008, Clin Cancer Res 14:6744-50), tolerated clinically at low doses with external radiotherapy (Pauwels et al, 2005, Oncologist 10:34-51), and preclinical studies showed enhanced anti-tumor activity combining ⁇ Y-labeled PAM4 with gemcitabine (Cardillo et al, 2002, Int J Cancer 97:386-92; Gold et al, 2003, Clin Cancer Res 9:39298- 37S; Gold et al, 2004, Int J Cancer 109:618-26).
  • This Example reports the results of an open-label, multicenter phase lb study of 9J Y- clivatuzumab tetraxetan administered with or without 200 mg/m' gemcitabine in patients with metastatic pancreatic adenocarcinoma after >2 prior therapies.
  • Primary study objectives included evaluating treatment safety and tolerability in this setting. Additional objectives were to obtain evidence of efficacy based on survival, CT imaging and CA19-9 serum levels, assess the contribution of gemcitabine to this treatment regimen, and evaluate any immunogenicity toward this antibody-based regimen.
  • Adverse events were graded by NCI-CTCAE v4.0 (National Cancer Institute (NCI). Common terminology criteria for adverse events (CTCAE) version 4.0). Vital signs, physical examination, blood counts, serum chemistries, and CA 19-9 serum levels were evaluated during treatment cycles, then 4, 8, and 12 weeks after l st cycle. Serum samples were evaluated by enzyme immunoassay for any human anti-hPAM4 antibodies ( ⁇ ). CT scans were interpreted by local radiologists every 4 weeks after each cycle until progression or 12 weeks post-treatment. Tumor lesion changes were categorized as a complete response (CR), partial response (PR), stable (SD), or progressive disease (PD) by RECIST vl.O [27]. i8 F-FDG-PET or PET/CT imaging was optional. All patients were followed for survival.
  • T Irinotecan, oxaliplatin, and 5-fluorouraeil leucovorin combination T Irinotecan, oxaliplatin, and 5-fluorouraeil leucovorin combination.
  • Adverse Events were thrombocytopenia, 50% of patients; fatigue, 26%; anemia, 22%; nausea, 16%; leukopenia, neutropenia, 12% each; abdominal pain, anorexia, vomiting, diarrhea, 9% each; bleeding, fever, chills, 7% each; dyspnea, hyperbilirubinemia, headache, 5% each: others ⁇ 5%.
  • thrombocytopenia 50% of patients; fatigue, 26%; anemia, 22%; nausea, 16%; leukopenia, neutropenia, 12% each; abdominal pain, anorexia, vomiting, diarrhea, 9% each; bleeding, fever, chills, 7% each; dyspnea, hyperbilirubinemia, headache, 5% each: others ⁇ 5%.
  • Grade >3 events of thrombocytopenia 19%; anemia, leukopenia, neutropenia, 7% each; others ⁇ 2%).
  • Headache 14 0 0 0
  • infections occurred in 1 1 (19%) patients, including 4 serious events [fatal septic entercolitis from pre-study pancreatectomy (Sump syndrome); fatal septic bacteremia from unidentified source; post-interventional Grade 3 acute cholangitis; Grade 3 pneumonia responding to antibiotics]; and 10 Grade 1-2 events [upper respiratory infection (URI) x 4, urinary tract infection (UTT) x 3, superficial fungal infection x 2, pneumonia, Lyme disease). The fatal bacteremia was considered possibly-related although the patient had a history of severe infections and recent biliary stent placement; other infections were considered unrelated by the investigators. Furthermore, only 3 patients were neutropenic (700 - 900 cells/ ⁇ .) at time of infection (pneumonia, UTI, URI ).
  • Treatment-related myelosuppression may have exacerbated two cases of consumptive coagulopathy, but otherwise, the few infections or major bleeding events that occurred could be attributed to complications of underlying disease. Most other AEs were mild-moderate constitutional and gastrointestinal events also expected in advanced pancreatic cancer, and comparison of events between treatment arms showed no substantial differences. Thus this combination approach appears to be an acceptable regimen in this advanced population.
  • the claimed methods and compositions utilize the antibody hPAM4 which is a humanized IgG of the murine PAM4 MAb raised against pancreatic cancer mucin. Humanization of the murine PAM4 sequences was utilized to reduce the human antimouse antibody (FIAMA) response. To produce the humanized P.AM4, murine complementarity determining regions (CDR) were transferred from heavy and light variable chains of the mouse immunoglobulin into human framework region (FR) antibody sequences, followed by the replacement of some human FR residues with their murine counterparts. Humanized monoclonal antibodies are suitable for use in in vitro and in vivo diagnostic and therapeutic methods.
  • CDR complementarity determining regions
  • variable region framework sequences of the murine PAM4 MAb (FIG. 8A and FIG. 8B) to known human antibodies in the abat database showed that the FRs of PAM4 V and VH exhibited the highest degree of sequence homology to that of the human antibodies Walker VK (FIG. 10A) and W112 V H (FIG. 10B), respectively. Therefore, the Walker VK (FIG. 10 A) and Wil2 V H (FIG. 10B) FRs were selected as the human frameworks into which the murine CDRs for PAM4 VK and V H were grafted, respectively.
  • the FR4 sequence of the human antibody, EWM was used to replace the Wil2 FR4 sequence for the humanization of the PAM4 heavy chain (FIG. 10B).
  • a few amino acid residues in PAM4 FRs that flank the putative CDRs were maintained in hPAM4 based on the consideration that these residues have more impact on Ag binding than other FR residues. These residues were 21M, 47W, 59P, 60A, 85S, 87F, and 100G of VK (FIG. 10A) and 27Y, 30P, 38 , 481, 66K, 67A, and 69L of V H (FIG. 10B).
  • the DNA and amino acid sequences of hPAM4 VK (SEQ ID NO: 16) and V H (SEQ ID NO: 19) are shown in FIG. 11A and 11B, respectively.
  • hPAM4 VRB represents the minus strand of the hPAM4 VH domain complementary to nt 169 to 341.
  • oligonucleotides Each annealed end serves as a primer for the transcription of the single stranded DNA, resulting in a double strand DNA composed of the nt 17 to 341 of hPAM4 VH.
  • This DNA was further amplified in the presence of two short oligonucleotides, hPAM4 VHBACK and hPAM4 V H FOR to form the full-length hPAM4 V H .
  • the underlined portions are restriction sites for subcloning as shown in FIG. ⁇ IB.
  • hPAM4 ⁇ ' ⁇ and VHB (determined empirically) was amplified in the presence of 10 ⁇ . of 10X PGR. Buffer (500 mM KC1, 100 mM Tris HC1 buffer, pH 8.3, 15 mM MgCl 2 ), 2 ⁇ of hPAM4 VHBACK and hPAM4 V K FOR, and 2.5 units of Taq DNA polymerase (Perkiri Elmer Cetus, Norwalk, Conn.). This reaction mixture was subjected to three cycles of polymerase chain reaction (PGR) consisting of denaturation at 94°C for 1 minute, annealing at 45°C for i minute, and polymerization at 72°C for 1.5 minutes.
  • PGR polymerase chain reaction
  • Double-stranded PCR-ampiified product for hPAM4 VH was gel-purified, restriction-digested with Psti and BstEll restriction sites and cloned into the complementary Pstl/BstEII restriction sites of the heavy chain staging vector, V H pBS2, in which the VH sequence was fully assembled with the DNA sequence encoding the translation initiation codon and a secretion signal peptide in-frame li gated at the 5 '-end and an intron sequence at the 3'-end.
  • V H pBS2 is a modified staging vector of V H pBS (Leung et al., Hybridoma, 13:469, 1994), into which a Xhol restriction site was introduced at sixteen bases upstream of the translation initiation codon to facilitate the next subcloning step.
  • the assembled VH gene was subeloned as a XhoI-BamHI restriction fragment into the expression vector, pdHL2, which contains the expression cassettes for both human IgG heavy and light chains under the control of IgH enhancer and MT1 promoter, as well as a mouse d/fr gene as a marker for selection and amplification.
  • hPAM4 V K pdHL2 Since the heavy chain region of pdHL2 lacks a BamHI restriction site, this ligation requires use of a linker to provide a bridge between the BamHI site of the variable chain and the Hindlll site present in the pdHL2 vector.
  • the resulting expression vectors were designated as hPAM4 V K pdHL2.
  • hPAM4 VKA 157-mer
  • hPAM4 V K B 156-mer
  • hPAM4 V K A and V K B were amplified by two short oligonucleotides hPAM4 VKBACK and hPAM4 VKFOR as described above.
  • nPAM4 V K A represents nt 16 to 172 of the hPAM4 VK domain.
  • hPAM4 VRB represents the minus strand of the hPAM4 VK domain complementary to nt 153 to 308,
  • hPAM4 V K A and VRB anneal to form a short double-stranded DNA flanked by the rest of the long oligonucleotides.
  • Each annealed end served as a primer for the transcription of the single stranded DNA, resulting in a double strand DN A composed of nt 16 to 308 of hP AM4 VK.
  • This DNA was further amplified in the presence of two short oligonucleotides, hPAM4 VKBACK and hPAM4 V K FOR to form the full-length hPAM4 VK,
  • the underlined portions are restriction sites for subcloning as described below.
  • V ' KPBR2 is a modified staging vector of Vi B (Leung et al., Hybridoma, 13:469, 1994), into which a Xbal restriction site was introduced at sixteen bases upstream of the translation initiation codon.
  • the assembled V genes were subeloned as Xhal-BarriHI restriction fragments into the expression vector containing the VR sequence, hPAM4 ViipdHI.2.
  • the resulting expression vectors were designated as hPAM4pdHL2.
  • hPAM4pdHL2 was linearized by digestion with Sail and transfected into 8p2/0-Agl4 cells by electroporation at 450 V and 25 ⁇ .
  • the transfected cells were plated into 96-well plates and incubated in a CQ 2 cell culture incubator for two days and then selected for MTX resistance. Colonies surviving selection emerged in two to three weeks and were screened for human antibody secretion by ELISA assay. Briefly, supernatants (- 100 ul) from the surviving colonies were added into the wells of an ELISA microplate precoated with goat anti-human IgO F(ab') 2 fragment-specific Ab. The plate was incubated for one hour at room temperature.
  • Unbound proteins were removed by washing three times with wash buffer (PBS containing 0.05% Tween-20). Horseradish peroxidase- conjugated goat anti-human IgG Fc fragment- specific Ab was added to the wells. Following incubation for one hour, a substrate solution (100 .uL/weil) containing 4 mM 0- phenylenediamine dihydrochloride (OPD) and 0.04% HjOji PBS was added to the wells after washing. Color was allowed to develop in the dark for 30 minutes and the reaction was stopped by the addition of 50 ⁇ £ of 4 N H 2 SO 4 solution. The bound human IgG was measured by reading the absorbance at 490 nm on an ELISA reader. Positive cell clones were expanded and hPAM4 was purified from cell culture supernatant by affinity chromatography on a Protein A column.
  • the Ag-binding activity of hPAM4 was confirmed by ELISA assay in a micro titer plate coated with pancreas cancer cell extracts.
  • An ELISA competitive binding assay using PAM4- ntigen coated plates was developed to assess the Ag-binding affinity of hPAM4 in comparison with that of a chimeric PAM4 composed of murine V and human C domains.
  • Constant amounts of the HRP-conjugated cPAM4 mixed with varying concentrations of cPAM4 or hPAM4 were added to the coated wells and incubated at room temperature for 1-2 h.
  • the amount of HRP-conjugated cPAM4 bound to the CaPanl Ag was revealed by reading the absorbance at 490 nm after the addition of a substrate solution containing 4 mM 0- phenylenediamine dihydrochloride and 0.04% H 2 0 2 . As shown by the competition assays in FIG. 12, hPAM4 and cPAM4 antibodies exhibited similar binding activities.
  • PAM4 was reactive with twenty one out of twenty five (85%) pancreatic cancers (Table 9 and Table 10) and ten out of twenty six colon cancers, but only limited reactivity with tu mors of the stomach, lung, breast, ovary, prostate, liver or kidney (Table 10). PAM4 reactivity appeared to correlate with the stage of tumor differentiation, with a greater percentage of staining observed in well differentiated pancreatic cancers than in moderately differentiated or poorly differenti ted tumors. Generally, poorly differentiated tumors represent less than 10% of all pancreatic cancers.
  • PAM4 was found to be only weakly reactive with three out of twelve chronic pancreatitis specimens, whereas CA19.9 and DUPAN2 were strongly reactive with all twelve specimens. Although it is recognized that specificity is dependent in part upon the type of assay employed and the range and number of tissues examined, the ability of PAM4 to discriminate between normal and neoplastic pancreatic tissue, its ability to react with a large percentage of the cancer specimens, the high intensity of the reactions, and the ability to distinguish between early stage pancreatic cancer and benign conditions such as pancreatitis are important characteristics of this exemplary anti-pancreatic cancer antibody.
  • a - values are mean from two autopsy specimens
  • the biodistribution data were used to estimate potential radiation doses to the tumor of 12,230; 10,684; 6,835; and 1 ,843 cGy/mCi of injected dose to AsPc l , BxPc3, IIs766T and CaPanl , respeciively.
  • MTD maximum tolerated dose
  • PAM4 could provide substantial rad dose to each of the xenografted tumor models.
  • the blood levels of radiolabeled PAM4 were significantly (P ⁇ 0.01-0.001 lower than the nonspecific Ag8.
  • Potential radiation doses to the blood from PAM4 were 1.4-4.4 fold lower than from Ag8.
  • the tumors received doses that were 2,2; 3.3; 3.4; and 13.1 -fold higher than blood, respectively.
  • PAM4 showed no evidence of targeting to normal tissues, except in the CaPanl tumor model, where a small but statistically significant splenic uptake was observed (range 3.1- 7.5% ID/g on day-3). This type of splenic targeting has been observed in the clinical application of the anti-mucin antibodies B72.3 and CC49. Importantly, these studies also reported that splenic targeting did not affect tumor uptake of antibody nor did it interfere with interpretation of the nuclear scans.
  • splenic targeting was not du e to crossreactive antigens in the spleen, nor to binding by Fc receptors, but rather to one or more of the following possibilities: direct targeting of antigen trapped in the spleen, or indirect uptake of antigen:antibody complexes formed either in the blood or released from the tumor site. The latter would require the presence of immune complexes in the blood.
  • a single 350 ⁇ € ⁇ dose was not as effective against larger tumors, a single dose may not be the appropriate regimen for large tumors.
  • Toxicity studies indicate the ability to give multiple cycles of radioimmunotherapy , which may be more effective with a larger tumor burden.
  • the untreated group had a mean survival time of 3.7 ⁇ 1.0 weeks (survival defined as time for tumor to reach 5 cm 3 ). Animals died as early as three weeks, with no animal surviving past six weeks, A single dose of 350 ⁇ & ' " ''l- P.AM4 produced a significant increase in the survival time to 1 8.8 ⁇ 4.2 weeks (PO.0001 ).
  • the range of animal deaths extended from weeks thirteen to twenty five. None of the animals were alive at the end of the study period of twenty six weeks.
  • Radiolabeled PAM4 provided a significant survival advantage ( ⁇ 0.001) as compared to the untreated or Ag8 treated animals, with 70% survival at sixteen weeks, the end of the experiment. At this time the surviving animals were sacrificed to determine tumor size. All animals had tumor with an average weight of 1.2 g, as well as one or two small ( ⁇ 0.1 g) metastases evident in four of the seven animals. At sixteen weeks of gro wth, these tumors were more representative of an eight-week-old tumor.
  • the PAM4 antibody appears to bind to the same antigenic protein as the 45M1 anti-MUC5AC MAb, it is noted that MUC5AC is not specific to pancreas cancer and it is found in a number of normal tissues (other than the gastric mucosa with which PAM4 is reactive). For example, MUC5. C is found in normal lung, colon and other tissues. PAM4 antibody does not bind to normal lung tissues, except as indicated above in few samples and to a limited or minimal amount.
  • PAM4 antibody binding was examined with two different phage display peptide libraries.
  • the first was a linear peptide library consisting of 12 amino acid sequences and the second was a cyclic peptide consisting of 7 amino acid sequences cyclized by a disulfide bridge.
  • Phage binding in a non-specific manner i.e., binding to epratuzumab [hLL2]) were discarded.
  • the sequence WTWNITKAYPLP (SEQ ID NO:7) was identified 30 times (in 35 sequenced phage), each of which were shown to have reactivity with PAM4 antibodies, A mutational analysis was conducted in which a library- based on this sequence and having 7.5% degeneracy at each position, was constructed, panned and screened as before. Variability was noted in the 19 obtained peptide sequences that were positive for PAM4 binding with 7 being identical to the parental sequence, 5 having the sequence WTWNITKEYPQP (SEQ ID NO:65) and the rest being uniquely present. Table 11 shows the results of this mutational analysis.
  • the upper row lists the sequences identified and the lo were ro w lists the frequency with which each of the amino acids was identified in that position.
  • the parent sequence is most frequent (bold) with the next highest variation a substitution of E for A at position 8 and a substitution of Q for I. at position 1 1. It does not appear that these substitutions had any great effect upon immunoreactivity.
  • GTTGTTC (SEQ ID NO:67) is present within the MUC5AC protein towards the amino terminus as compared to the cyclic peptide sequence shown above, which shows homology at the C-terminal end of the consensus peptide sequence.
  • the cyclic peptide only showed approximately 10% of the immunoreactivity of the linear sequence with the PAM4 antibody.
  • Both linear and cyclic consensus sequences are associated with a cysteine, which may or may not relate to the effect of DTT on MUC5AC immunoreactivity.
  • Example 12 Immunohistology of Pancreatic Cancer in a Pancreatitis Specimesi
  • pancreatic carcinoma such as pancreatitis, diabetes, smoking and others.
  • screening measures are particularly important for the early detection of pancreatic neoplasia.
  • Patient 1 18-001, CWG, is a 63-year-old man with Stage-lV pancreatic
  • adenocarcinoma with multiple liver metastases diagnosed in November of 2007.
  • Example 14 Therapy of a Patient with inoperable Metastatic Pancreatic
  • Y-DOTA-hPAM4 radiolabeled humanized antibody is administered at a dose of 10 mCi/iiT of 90 Y and 2.0 mg antibody protein, in a two-hour i.v. infusion.
  • the patient is given a course of gemcitabine chemotherapy consisting of 3 weekly doses of 600 mg/rrf by i.v. infusion.
  • the patient is then evaluated 4 weeks later, and has a mild leukopenia (grade-2), no other major blood or enzyme changes over baseline, but shows an improvement in the blood CA19.9 titer from 5,700 to 1,200 and a decrease in jaundice, with an overall subjective improvement.
  • grade-2 mild leukopenia
  • This follows 3 weeks later with a repeat of the cycle of lower-dose gemcitabine (weekly x 4), with 3 doses of 90 Y-DOTA- hPAM4.
  • the patient is reevaluated, and the CT and PET scans confirm an approximately 40% reduction of total tumor mass (primary cancer and metastases), with a further reduction of the CA19.9 titer to 870.
  • the patient regains appetite and activity, and is able to return to more usual daily activities without the need for pain medication. He gains 12 lbs after beginning this experimental therapy. A repeat of the scans and blood values indicates that this response is maintained 6 weeks later.
  • the DNLTM technique can be used to make dimers, trimers, tetramers, hexamers, etc. comprising virtually any antibodies or fragments thereof or other effector moieties.
  • IgG antibodies or Fab antibody fragments may be produced as fusion proteins containing either a dimerization and docking domain (DDD) or anchoring domain (AD) sequence.
  • DDD and AD moieties are produced as fusion proteins, the skilled artisan will realize that other methods of conjugation, such as chemical cross-linking or click chemistry, may be utilized within the scope of the claimed methods and compositions.
  • Bispecific antibodies may be formed by combining a Fab-DDD fusion protein of a first antibody with a Fab- AD fusion protein of a second antibody.
  • constructs may be made that combine IgG-AD fusion proteins with Fab-DDD fusion proteins.
  • the technique is not limiting and any protein or peptide of use may be produced as an AD or DDD fusion protein for incorporation into a DNLTM construct.
  • the AD and DDD conjugates are not limited to proteins or peptides and may comprise any molec ule that may be cross-linked to an AD or DDD sequence using any cross - linking technique known in the art.
  • a polyethylene glycol (PEG) or other polymeric moiety may be incorporated into a D LTM construct, as described in further detail below.
  • an antibody or fragment containing a binding site for an antigen associated with a diseased tissue such as a tumor-associated antigen (TAA)
  • TAA tumor-associated antigen
  • a second antibody or fragment that binds a hapten on a targetable construct to which a therapeutic and/or diagnostic agent is attached.
  • TAA tumor-associated antigen
  • the DNLTM-based bispecific antibody is administered to a subject, circulating antibody is allowed to clear from the blood and localize to target tissue, and the conjugated targetable construct is added and binds to the localized antibody for diagnosis or therapy.
  • Independent transgenic cell lines may be developed for each Fab or IgG fusion protein. Once produced, the modules can be purified if desired or maintained in the cell culture supernatant fluid. Following production, any DDD-fusion protein module can be combined with any AD-fusion protein module to generate a bispecific DNLTM construct. For different types of constructs, different AD or DDD sequences may be utilized. Exemplary DDD and AD sequences are provided below.
  • DDD2 CGHIQIPPGLTELLQGYTVEVLRQQPPDLVEFAVEYFTRLREARA (SEQ ID NO:
  • AD 1 QIEYLA QIVDNAIQQA (SEQ ID NO: 70)
  • AD2 CGQIEYLAKQIVDNAIQQAGC (SEQ ID NO:7i)
  • DDDl and DDD2 comprise the DDD sequence of the human Rlla form of protein kinase A.
  • the DDD and AD moieties may be based on the DDD sequence of the human Rla form of protein kinase A and a corresponding AKAP sequence, as exemplified in DDD3, DDD3C and AD3 below.
  • the plasmid vector pdHL2 has been used to produce a number of antibodies and antibody-based constructs. See Gillies et al., J Immunol Methods ( 1989), 125 : 191 -202; Losman et al., Cancer (Phila) (1997), 80:2660-6.
  • the di-cistronic mammalian expression vector directs the syn thesis of the heavy and light chains of IgG.
  • the vector sequences are mostly identical for many different IgG-pdHL2 constracts, with the only differences existing in the variable domain (VH and VL) sequences.
  • these IgG expression vectors can be converted into Fab-DDD or Fab- D expression vectors.
  • the coding sequences for the hinge, CH2 and CH3 domains of the heavy chain are replaced with a sequence encoding the first 4 residues of the hinge, a 14 residue Gly-Ser linker and the first 44 residues of human Rlla (referred to as DDD 1).
  • AD l A AP-Z.S'
  • Two shuttle vectors were designed to facilitate the conversion of TgG-pdHL2 vectors to either Fab-DDD 1 or Fab-AD i expression vectors, as described below.
  • the CH I domain was amplified by PGR using the pdHL2 plasmid vector as a template.
  • the left PGR primer consisted of the upstream (5 ') end of the CHI domain and a SacII restriction endonuclease site, which is 5' of the CHI coding sequence.
  • the right primer consisted of the sequence coding for the first 4 residues of the hinge (PKSC (SEQ ID NO:
  • the 410 bp PGR amplimer was cloned into the PGEMT® PGR cloning vector (PROMEGA®, Inc.) and clones were screened for inserts in the T7 (5'j orientation.
  • duplex oligonucleotide designated (G 4 S) 2 DDD1 ('(G 4 S) 2 ' disclosed as SEQ ID NO:
  • oligonucleotides designated RJIA1-44 top and R.IIA1-44 bottom, which overlap by 30 base pairs on their 3' ends, were synthesized and combined to comprise the central 154 base pairs of the 174 bp DDD1 sequence.
  • the oligonucleotides were annealed and subjected to a primer extension reaction with Taq polymerase. Following primer extension, the duplex was amplified by PCR. The amplimer was cloned into PGEMT® and screened for inserts in the T7 (5') orientation.
  • a duplex oligonucleotide was synthesized to code for the amino acid sequence of AD1 preceded by 1 1 residues of the linker peptide with the first two codons comprising a BamHI restriction site. A stop codon and an Eagl restriction site are appended to the 3 'end. The encoded polypeptide sequence is shown belo w.
  • AKAP-IS Top and AKAP-IS Bottom Two complimentary overlapping oligonucleotides encoding the above peptide sequence, designated AKAP-IS Top and AKAP-IS Bottom, were synthesized and annealed. The duplex was amplified by PCR. The amplimer was cloned into the PGEMT® vector and screened for inserts in the T7 (5') orientation.
  • a 190 bp fragment encoding the DDD1 sequence was excised from PGEMT® with BamHI and Notl restriction enzymes and then ligated into the same sites in CFll -PGEMT® to generate the shuttle vector CHI -DDD1 -PGEMT®.
  • CHl-DDDl or CHl -AD l can be incorporated into any IgG construct in the pdHL2 vector.
  • the entire heavy chain constant domain is replaced with one of the above constructs by removing the Saell/Eagl restriction fragment (CHI -CHS) from pdHL2 and replacing it with the SacII/EagI fragment of CHl-DDDl or CHl -ADl , which is excised from the respective pGemT shuttle vector.
  • CHI -CHS Saell/Eagl restriction fragment
  • h679-Fd-AD 1 -pdHL2 is an expression vector for production ofh679 Fab with AD 1 coupled to the carboxyl terminal end of the CHi domain of the Fd via a flexible Gly/Ser peptide spacer composed of 14 amino acid residues.
  • a pdHL2-based vector containing the variable domains of h679 was converted to h679-Fd-AD 1 -pdHL2 by replacement of the Sacil/Eagi fragment with the CHl -ADl fragment, which was excised from the CHI -AD! - SV3 shuttle vector with SacII and Eagl.
  • C-DDD 1 -Fd-bMN- 14-pdHL2 is an expression vector for production of a stable dimer that comprises two copies of a fusion protein C-DDD I -Fab-hMN- 14, in which DDD1 is linked to hMN-14 Fab at the carboxyl terminus of CHI via a flexible peptide spacer.
  • the plasmid vector hMN- 14(l)-pdHL2 which has been used to produce hMN-14 IgG, was converted to C-DDD l-Fd-hMN-14-pdHL2 by digestion with SacII and Eagl restriction endonuc leases to remove the CH1-CH3 domains and insertion of the CHl-DDD l fragment, which was excised from the CH1-DDD -SV3 shuttle vector with SacII and Eagl.
  • AD- and DDD-fusion proteins comprising a Fab fragment of any of such antibodies may be combined, in an approximate ratio of two DDD-fusion proteins per one AD-fusion protein, to generate a trimerie DNLTM construct comprising two Fab fragments of a first antibody and one Fab fragment of a second antibody.
  • C-DDD2-Fd-hMN- 14-pdHL2 is an expression vector for production of C-DDD2-Fab- hMN-14, which possesses a dimerization and docking domain sequence of DDD2 appended to the carboxyl terminus of the Fd of hMN-14 via a 14 amino acid residue Gly/Ser peptide linker.
  • the fusion protein secreted is composed of two identical copies of hMN- 14 Fab held together by non-covalent interaction of the DDD2 domains.
  • the expression vector was engineered as follows. Two overlapping, complimentary oligonucleotides, which comprise the coding sequence for part of the linker peptide and residues 1 - 13 of DDD2, were made synthetically. The oligonucleotides were annealed and phosphoryl ted with T4 PNK, resulting in overhangs on the 5' and 3' ends that are compatible for ligation with DNA digested with the restriction endonucleases BamHT and PstT, respectively.
  • the duplex DMA was ligated with the shuttle vector CH1-DDD1-PGEMT®, which was prepared by digestion with BamHl and Pstl, to generate the shuttle vector CH1 -DDD2- PGEMT®.
  • a 507 bp fragment was excised from CH 1 -DDD2-PGEMT® with SacII and Eagl and ligated with the IgG expression vector hMN-14(I)-pdHL2, which was prepared by digestion with SacII and Eagl.
  • the final expression construct was designated C-DDD2-Fd- hMN- 14 ⁇ pdHL2. Similar techniques have been utilized to generated DDD2-fusion proteins of the Fab fragments of a number of different humanized antibodies.
  • h679-Fab-AD2 was designed to pair as B to C-DDD2-Fab-hMN- 14 as A
  • h679-Fd- AD2-pdHL2 is an expression vector for the production of h679-Fab-AD2, which possesses an anchoring domain sequence of AD2 appended to the carboxyl terminal end of the CHI domain via a 14 amino acid residue Gly/Ser peptide linker.
  • AD2 has one cysteine residue preceding and another one following the anchor domain sequence of AD ! .
  • the expression vector was engineered as follows. Two overlapping, complimentary oligonucleotides (AD2 Top and AD2 Bottom), which comprise the coding sequence for AD2 and part of the linker sequence, were made synthetically. The oligonucleotides were annealed and phosphorylated with T4 PNK, resulting in overhangs on the 5' and 3 s ends that are compatible for ligation with DNA digested with the restriction endonucleases BamHI and Spel, respectively.
  • duplex DNA was ligated into the shuttle vector CH 1 - AD 1 -PGEMT®, which was prepared by digestion with BamHI and Spel, to generate the shuttle vector CH1 -AD2- PGEMT®.
  • a 429 base pair fragment containing CHI and AD2 coding sequences was excised from the shuttle vector with SacII and Eagl restriction enzymes and ligated into h679-pdHL2 vector that prepared by digestion with those same enzymes.
  • the final expression vector is b679-Fd-AD2-pdHL2.
  • the IgG and Fab fusion proteins shown in Table 14 were constructed and incorporated into DNLTM constructs.
  • the fusion proteins retained the antigen-binding characteristics of the parent antibodies and the DNLTM constructs exhibited the antigen-binding activities of the incorporated antibodies or antibody fragments.
  • Table 14 Fusion proteins comprising IgG or Fab
  • the AD and DDD sequences incorporated into the DNLTM construct comprise the amino acid sequences of AD1 , AD2, AD3, DDD 1 , DDD2, DDD3 or DDD3C as discussed above.
  • sequence v ariants of AD and/or DDD moieties may be utilized in construction of the DNLTM complexes.
  • th re are only four variants of human PKA.
  • the Rlla DDD sequence is the basis of DDD 1 and DDD2 disclosed above.
  • the four human PKA DDD sequences are shown below.
  • the DDD sequence represents residues 1 -44 of Rlla, 1 -44 of Rlip, 12-61 ofRIa and 13-66 of Rip. (Note that the sequence of DDD 1 is modified slightly from the human PKA Rlla DDD moiety.)
  • SIEIPAGLTELLQGFTVEVLRHQPADLLEFALQHFTRLQQENER SEQ ID NO:80
  • the structure- function relationships of the AD and DDD domains have been the subject of investigation. (See, e.g., Burns-Hamuro et al., 2005, Protein Sci 14:2982-92; Can et al, 2001 , J Biol Chem 276: 17332-38; Alto et al., 2003, Proc Natl Acad Sci USA 100:4445- 50; Hundsrucker et al, 2006, Biochem J 396:297-306; Stokka et al., 2006, Biochem J 400:493-99; Gold et al., 2006, Mol Cell 24:383-95; Kinderman et al., 2006, Mol Cell 24:397- 408, the entire text of each of which is incorporated herein by reference.)
  • Alto et al. (2003) performed a bioinformatie analysis of the AD sequence of various AKAP proteins to design an RI! selective AD sequence called AKAP-TS (SEQ ID NO:70), with a binding constant for DDD of 0.4 nM.
  • the AKAP-IS sequence was designed as a peptide antagonist of AKAP binding to PKA. Residues in the AKAP-IS sequence where substitutions tended to decrease binding to DDD are underlined in SEQ ID NO:70.
  • sequence variants of the AD sequence one would desirably avoid changing any of the underlined residues, while conservative amino acid substitutions might be made for residues that are less critical for DDD binding.
  • the SuperAKAP-IS sequence may be substituted for the AKAP-IS AD moiety sequence to prepare DNLTM constructs.
  • Other alternative sequences that might be substituted for the AKAP-IS AD sequence are shown in SEQ ID NO:82-84. Substitutions relative to the AKAP-IS sequence are underlined. It is anticipated that, as with the AD2 sequence shown in SEQ ID NO:68. the AD moiety may also include the additional N-terminal residues cysteine and glycine and C- terminal residues glycine and cysteine,
  • Figure 2 of Gold et al. disclosed additional DDD-binding sequences from a variety of AKAP proteins, shown below.
  • MAP2D TAEEVSARIVQVVTAEAV SEQ ID NO: 92
  • AKAP7 ⁇ 5-L308D-pep PEDAELVRLSKRDVENAVLKAVQQY (SEQ ID NO: 103)
  • AKAP7()-P ⁇ pep PEDAELVRLSKRLPENAVLKA VQQY (SEQ ID NO: 104)
  • AKAP7 ⁇ S-PP-pep PEDAELVRLSKRLPENAPLKAVQQY (SEQ ID NO: 105)
  • AKAP9-pep LEKQ Y QEQLEEEV AK YTVSMSIAFA (SI iQ ID NO: 1 10)
  • AKAPl O-pep NTDEAQEELAWKIAKMIVSDIMQQA i sEQ ID NO: 1 1 1
  • AKAPl I -pep VNLDKKAVLAEKIVAEAIEKAEREL S: EQ ID NO: 1 12
  • AKAP12-pep NGILELETKSSKLVQNIIQTAVDQF (SEQ ID NO: l 13)
  • Carr et al. (2.001 ) examined the degree of sequence homology between different AKAP-binding DDD sequences from human and non-human proteins and identified residues in the DDD sequences that appeared to be the most highly conserved among different DDD moieties. These are indicated below by underlining with reference to the human PKA Rlla DDD sequence of SEQ ID NO:68. Residues that were particularly conserved are farther indicated by italics. The residues overlap with, but are not identical to those suggested by Kinderman et al. (2006) to be important for binding to AKAP proteins.
  • SHiQIPVGLTELLQGYTVEVLRQOPWJLVEFAYEYFTRIMEARA SEQ ID NO:68
  • the skilled artisan will realize thai these and other amino acid substitutions in the antibody moiety or linker portions of the DNLTM constructs may be utilized to enhance the therapeutic and/or pharmacokinetic properties of the resulting DNLTM constructs.
  • a trimeric DNLTM construct designated TF2 was obtained by reacting C-DDD2-Fab- hMN-14 with h679-Fab-AD2.
  • a pilot batch of TF2 was generated with >90% yield as follows.
  • Protein L-purified C-DDD2 -Fab-hMN- 14 200 mg was mixed with h679-Fab-AD2 (60 mg) at a 1.4: 1 molar ratio.
  • the total protein concentration was 1.5 mg ml in PBS containing 1 mM EDTA.
  • Subsequent steps involved T ' CEP reduction, HIC chromatography, DMSO oxidation, and IMP 291 affinity chromatography.
  • Non-reducing SDS-PAGE analysis demonstrated that the majority of TF2 exists as a large, covalent structure with a relative mobility near that of IgG (not shown). The additional bands suggest that disulfide formation is incomplete under the experimental conditions (not shown). Reducing SDS-PAGE shows that any additional bands apparent in the non-reducing gel are product-related (not shown), as only bands representing the constituent polypeptides of TF2 were evident (not shown). However, the relative mobilities of each of the four polypeptides were too close to be resolved. MALDT-TOF mass spectrometry (not shown) revealed a single peak of 156,434 Da, which is within 99.5% of the calculated mass ( 157,319 Da) of TF2.
  • TF2 The functionality of TF2 was determined by BIACORE® assay.
  • TF2, C-DDD 1- hMN- 14+h679-AD 1 (used as a control sample of noncovalent a3 ⁇ 4 complex), or C-DDD2- hMN-14-4i679-AD2 (used as a control sample of unreduced a? and b components) were diluted to 1 ⁇ ig/mi (total protein) and passed over a sensorchip immobilized with HSG.
  • the response for TF2 was approximately two-fold that of the two control samples, indicating that only the h679-Fab-AD component in the control samples would bind to and remain on the sensorchip.
  • TF10 DNLTM construct comprising two copies of a C-DDD2-Fab-hPAM4 and one copy of C-AD2-Fab-679.
  • the cancer- targeting antibody component in TFl 0 was derived from liPAM4, a humanized anti- MUC5AC MAb that has been studied in detail as a radiolabeled MAb (e.g., Gold et al., Clin. Cancer Res. 13: 7380-7387, 2007).
  • the hapten-binding component was derived from h679, a humanized anti-hisiaminyi-succinyi-giycine (HSG) MAb.
  • the TF10 bispecific ([hPAM4] 2 x h679) antibody was produced using the method disclosed for production of the (anti CEA)2 x anti HSG bsAb TF2, as described above.
  • the TF10 construct bears two humanized PAM4 Fabs and one humanized 679 Fab.
  • tissue culture supernatant fluids were combined, resulting in a two-fold molar excess of hPAM4-DDD.
  • the reaction mixture was incubated at room temperature for 24 hours under mild reducing conditions using 1 mM reduced glutathione. Following reduction, the DNLTM reaction was completed by mild oxidation using 2 mM oxidized glutathione.
  • TF10 was isolated by affinity chromatography using IMP 291-affigel resin, which binds with high specificity to the h679 Fab.
  • hP AM4 igG A full tissue histology and blood cell binding panel has been examined for hP AM4 igG and for an anti-CEA x anti-FiSG bsMAb that is entering clinical trials.
  • hPAM4 binding was restricted to very weak binding to the urinary bladder and stomach in 1/3 specimens (no binding was seen in vivo), and no binding to normal tissues was attributed to the anti-CEA x anti-HSG bsMAb.
  • Example 20 Imaging Siisdies Using Pretargeting With TFIO Bispecific Antibody and iil In-LabeIed Peptides
  • the following study demonstrates the feasibility of in vivo imaging using the pretargeting technique with bispecific antibodies incorporating hPAM4 and labeled peptides.
  • the TF10 bispecific antibody comprising two copies of a C-DDD2-Fab-hPAM4 and one copy of C-AD2-Fab-679, was prepared as described in the preceding Example, Nude mice bearing 0.2 to 0.3 g human pancreatic cancer xenografts were imaged, using pretargeting with TFIO and m In-IMP-288 peptide.
  • FIG. 15A and FIG. 15B The results, shown in FIG. 15A and FIG. 15B,

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Abstract

La présente invention concerne des compositions et des procédés d'utilisation d'anticorps ou de fragments d'anticorps qui se lient à un épitope situé dans le second domaine riche en cystéine (Cys2, résidus d'acides aminés 1575-1725) de MUC5AC. Les anticorps se lient au cancer du pancréas avec une spécificité et une sélectivité élevées, et sont utilisés pour la thérapie, la détection et/ou le diagnostic de cancer du pancréas. Dans des modes de réalisation préférés, un anticorps thérapeutique peut être conjugué à au moins un agent thérapeutique, tel que 90Y. Une détection à la fois in vivo et in vitro du cancer du pancréas peut être réalisée avec les procédés et les compositions de l'invention. L'invention concerne des dosages spécifiques de gemcitabine et/ou d'anticorps radiomarqué, utilisés chez des patients humains atteints du cancer du pancréas.
PCT/US2015/038252 2014-06-30 2015-06-29 Anticorps réagissant avec un épitope situé dans la région n-terminale de muc5ac comprenant un sous-domaine 2 riche en cystéine (cys2) WO2016003869A1 (fr)

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EP15815785.9A EP3160499A4 (fr) 2014-06-30 2015-06-29 Anticorps réagissant avec un épitope situé dans la région n-terminale de muc5ac comprenant un sous-domaine 2 riche en cystéine (cys2)

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US14/632,480 2015-02-26
US14/632,480 US9238084B2 (en) 2003-06-16 2015-02-26 Anti-mucin antibodies for early detection and treatment of pancreatic cancer
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WO2023056240A3 (fr) * 2021-09-28 2023-05-04 Frontaim Biomedicines, Inc. Formats multiples de complexes moléculaires
CN114276980A (zh) * 2021-12-29 2022-04-05 王意忠 一种培养适合临床应用的胰岛细胞的方法
CN114276980B (zh) * 2021-12-29 2023-12-05 王意忠 一种培养适合临床应用的胰岛细胞的方法

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