title: TetraMabs: simultaneous targeting of four oncogenic receptor tyrosine kinases for tumor growth inhibition in heterogeneous tumor cell populations.
abstract: Monoclonal antibody-based targeted tumor therapy has greatly improved treatment options for patients. Antibodies against oncogenic receptor tyrosine kinases (RTKs), especially the ErbB receptor family, are prominent examples. However, long-term efficacy of such antibodies is limited by resistance mechanisms. Tumor evasion by a priori or acquired activation of other kinases is often causative for this phenomenon. These findings led to an increasing number of combination approaches either within a protein family, e.g. the ErbB family or by targeting RTKs of different phylogenetic origin like HER1 and cMet or HER1 and IGF1R. Progress in antibody engineering technology enabled generation of clinical grade bispecific antibodies (BsAbs) to design drugs inherently addressing such resistance mechanisms. Limited data are available on multi-specific antibodies targeting three or more RTKs. In the present study, we have evaluated the cloning, eukaryotic expression and purification of tetraspecific, tetravalent Fc-containing antibodies targeting HER3, cMet, HER1 and IGF1R. The antibodies are based on the combination of single-chain Fab and Fv fragments in an IgG1 antibody format enhanced by the knob-into-hole technology. They are non-agonistic and inhibit tumor cell growth comparable to the combination of four parental antibodies. Importantly, TetraMabs show improved apoptosis induction and tumor growth inhibition over individual monospecific or BsAbs in cellular assays. In addition, a mimicry assay to reflect heterogeneous expression of antigens in a tumor mass was established. With this novel in vitro assay, we can demonstrate the superiority of a tetraspecific antibody to bispecific tumor antigen-binding antibodies in early pre-clinical development.
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Raffaella
authors: R
authors: Castoldi
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Jürgen
authors: J
authors: Schanzer
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Christian
authors: C
authors: Panke
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Ute
authors: U
authors: Jucknischke
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Natalie J
authors: NJ
authors: Neubert
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Rebecca
authors: R
authors: Croasdale
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Werner
authors: W
authors: Scheuer
authors: pRED, Roche Pharma Research & Early Development, Roche Large Molecule Research, Roche Innovation Center, Munich, Nonnenwald 2, 82377 Penzberg, Germany.
authors: Johannes
authors: J
authors: Auer
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Zuerich, Switzerland, Wagistrasse 18, 8952 Schlieren.
authors: Christian
authors: C
authors: Klein
authors: pRED, Roche Pharma Research & Early Development, Roche Innovation Center, Munich, Germany.
authors: Gerhard
authors: G
authors: Niederfellner
authors: Center of Integrated Protein Science Munich (CIPS-M) and Division of Clinical Pharmacology, Department of Medicine IV, Klinikum der Universität München, Lindwurmstraße 2a, 80337 Munich, Germany, Member of the German Center for Lung Research (DZL).
authors: Sebastian
authors: S
authors: Kobold
authors: pRED, Roche Pharma Research & Early Development, Roche Large Molecule Research, Roche Innovation Center, Munich, Nonnenwald 2, 82377 Penzberg, Germany.
authors: Claudio
authors: C
authors: Sustmann
mesh_terms: D000918:Antibody Specificity; D017209:Apoptosis / Q000276:immunology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D018920:Coculture Techniques; D004789:Enzyme Activation; D006801:Humans; D058990:Molecular Targeted Therapy / Q000379:methods*; D015202:Protein Engineering; D020794:Receptor Protein-Tyrosine Kinases / Q000276:immunology* / Q000378:metabolism; D057127:Single-Chain Antibodies / Q000235:genetics / Q000276:immunology*
chemical_list: D057127:Single-Chain Antibodies; D020794:Receptor Protein-Tyrosine Kinases
keywords: EGFR; HER3; IGF1R; cMet; cancer; receptor tyrosine kinase; tetraspecific antibody; therapeutic antibody