title: T cell-engaging BiTE antibodies specific for EGFR potently eliminate KRAS- and BRAF-mutated colorectal cancer cells.
abstract: Epidermal growth factor receptor (EGFR)-specific monoclonal antibodies predominantly inhibit colorectal cancer (CRC) growth by interfering with receptor signaling. Recent analyses have shown that patients with CRC with mutated KRAS and BRAF oncogenes do not profit from treatment with such antibodies. Here we have used the binding domains of cetuximab and pantitumumab for constructing T cell-engaging BiTE antibodies. Both EGFR-specific BiTE antibodies mediated potent redirected lysis of KRAS- and BRAF-mutated CRC lines by human T cells at subpicomolar concentrations. The cetuximab-based BiTE antibody also prevented at very low doses growth of tumors from KRAS- and BRAF-mutated human CRC xenografts, whereas cetuximab was not effective. In nonhuman primates, no significant adverse events were observed during treatment for 3 wk at BiTE serum concentrations inducing, within 1 d, complete lysis of EGFR-overexpressing cancer cells. EGFR-specific BiTE antibodies may have potential to treat CRC that does not respond to conventional antibodies.
authors.affiliation: Micromet, 81477 Munich, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Lutterbuese
authors.forename: Tobias
authors.initials: T
authors.lastname: Raum
authors.forename: Roman
authors.initials: R
authors.lastname: Kischel
authors.forename: Patrick
authors.initials: P
authors.lastname: Hoffmann
authors.forename: Susanne
authors.initials: S
authors.lastname: Mangold
authors.forename: Benno
authors.initials: B
authors.lastname: Rattel
authors.forename: Matthias
authors.initials: M
authors.lastname: Friedrich
authors.forename: Oliver
authors.initials: O
authors.lastname: Thomas
authors.forename: Grit
authors.initials: G
authors.lastname: Lorenczewski
authors.forename: Doris
authors.initials: D
authors.lastname: Rau
authors.forename: Evelyne
authors.initials: E
authors.lastname: Schaller
authors.forename: Ines
authors.initials: I
authors.lastname: Herrmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Wolf
authors.forename: Thomas
authors.initials: T
authors.lastname: Urbig
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Baeuerle
authors.forename: Peter
authors.initials: P
authors.lastname: Kufer
mesh_terms: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000235:genetics* / Q000473:pathology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011905:Genes, ras / Q000187:drug effects; D006801:Humans; D009154:Mutation / Q000187:drug effects; D009369:Neoplasms / Q000235:genetics; D048493:Proto-Oncogene Proteins B-raf; D012307:Risk Factors
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D066246:ErbB Receptors; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D000068818:Cetuximab