In an attempt to realize the opportunity of T cell co-stimulatory receptors but without the observed peripheral toxicities observed to date, Compte et al. utilized tumor targeting to direct T cell stimulation to the TME. A small collagen homotrimerizing domain was used to scaffold a trimeric bispecific antibody targeting EGFR (with a VHH domain) and 4-1BB (with a scFv). Biochemical and cell-based studies proved the high affinity, specificity, and targeted T cell stimulatory capacity, and in vivo studies demonstrated tumor control, dramatic CD8+ T cell infiltration, and immunological memory without apparent toxicity.
The costimulation of immune cells using first-generation anti-4-1BB monoclonal antibodies (mAbs) has demonstrated anti-tumor activity in human trials. Further clinical development, however, is restricted by significant off-tumor toxicities associated with FcgammaR interactions. Here, we have designed an Fc-free tumor-targeted 4-1BB-agonistic trimerbody, 1D8(N/C)EGa1, consisting of three anti-4-1BB single-chain variable fragments and three anti-EGFR single-domain antibodies positioned in an extended hexagonal conformation around the collagen XVIII homotrimerization domain. The1D8(N/C)EGa1 trimerbody demonstrated high-avidity binding to 4-1BB and EGFR and a potent in vitro costimulatory capacity in the presence of EGFR. The trimerbody rapidly accumulates in EGFR-positive tumors and exhibits anti-tumor activity similar to IgG-based 4-1BB-agonistic mAbs. Importantly, treatment with 1D8(N/C)EGa1 does not induce systemic inflammatory cytokine production or hepatotoxicity associated with IgG-based 4-1BB agonists. These results implicate FcgammaR interactions in the 4-1BB-agonist-associated immune abnormalities, and promote the use of the non-canonical antibody presented in this work for safe and effective costimulatory strategies in cancer immunotherapy.
Author Info: (1) Department of Antibody Engineering, Leadartis SL, 28008, Madrid, Spain. (2) Immunotherapy and Cell Engineering Laboratory, Department of Engineering, Aarhus University, 8000C,
Author Info: (1) Department of Antibody Engineering, Leadartis SL, 28008, Madrid, Spain. (2) Immunotherapy and Cell Engineering Laboratory, Department of Engineering, Aarhus University, 8000C, Aarhus, Denmark. (3) Crystallography and Protein Engineering Unit, Spanish National Cancer Research Centre (CNIO), 28029, Madrid, Spain. (4) Molecular Immunology Unit, Hospital Universitario Puerta de Hierro Majadahonda, 28222 Majadahonda, Madrid, Spain. (5) Department of Antibody Engineering, Leadartis SL, 28008, Madrid, Spain. (6) Instituto de Investigaciones Biomedicas Alberto Sols (IIBm), CSIC-UAM, 28029, Madrid, Spain. Instituto de Investigacion Sanitaria La Paz (IdiPaz), 28029, Madrid, Spain. (7) Department of Antibody Engineering, Leadartis SL, 28008, Madrid, Spain. (8) Structural Biology Unit, CIC bioGUNE, Parque Tecnologico de Bizkaia, 48160, Derio, Spain. (9) Molecular Immunology Unit, Hospital Universitario Puerta de Hierro Majadahonda, 28222 Majadahonda, Madrid, Spain. (10) Molecular Immunology Unit, Hospital Universitario Puerta de Hierro Majadahonda, 28222 Majadahonda, Madrid, Spain. (11) Immunotherapy and Cell Engineering Laboratory, Department of Engineering, Aarhus University, 8000C, Aarhus, Denmark. (12) Histopathology Unit, Spanish National Cancer Research Centre (CNIO), 28029, Madrid, Spain. (13) Molecular Immunology Unit, Hospital Universitario Puerta de Hierro Majadahonda, 28222 Majadahonda, Madrid, Spain. (14) Department of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain. (15) Immunotherapy and Cell Engineering Laboratory, Department of Engineering, Aarhus University, 8000C, Aarhus, Denmark. (16) Crystallography and Protein Engineering Unit, Spanish National Cancer Research Centre (CNIO), 28029, Madrid, Spain. (17) Department of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain. Department of Immunology, University Clinic, University of Navarra, 31008 Pamplona, Spain. Instituto de Investigacion Sanitaria de Navarra (IdISNA), 31008 Pamplona, Spain. CIBERONC-Centro virtual de Investigacion Biomedica en red de Oncologia, 28029 Madrid, Spain. (18) Structural Biology Unit, CIC bioGUNE, Parque Tecnologico de Bizkaia, 48160, Derio, Spain. IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain. (19) Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Research Complex at Harwell, OX11 0QX Harwell-Oxford, UK. Department of Physics, King's College London, WC2R 2LS London, UK. (20) Instituto de Investigaciones Biomedicas Alberto Sols (IIBm), CSIC-UAM, 28029, Madrid, Spain. Instituto de Investigacion Sanitaria La Paz (IdiPaz), 28029, Madrid, Spain. (21) Molecular Immunology Unit, Hospital Universitario Puerta de Hierro Majadahonda, 28222 Majadahonda, Madrid, Spain. (22) Immunotherapy and Cell Engineering Laboratory, Department of Engineering, Aarhus University, 8000C, Aarhus, Denmark. lav@eng.au.dk. Cancer Immunotherapy Unit (UNICA), Department of Immunology, Hospital Universitario 12 de Octubre, 28041, Madrid, Spain. lav@eng.au.dk. Immuno-Oncology and Immunotherapy Group, Instituto de Investigacion Sanitaria 12 de Octubre (i+12), 28041, Madrid, Spain. lav@eng.au.dk.
