Abstract DDT01-03: Discovery and preclinical pharmacology of JNJ-61186372: A novel bispecific antibody targeting EGFR and cMET

NSCLC with activating mutations in the EGFR gene are associated with high response rates to EGFR tyrosine kinase inhibitors (TKIs), such as erlotinib and gefitinib, but invariably acquired resistance emerges over time. A primary cause of resistance is the emergence of secondary mutations in EGFR which neutralize the effectiveness of TKIs. In addition, the cMet pathway is often activated, either through MET gene amplification, overexpression of cMet protein, or an increase in the ligand HGF, to provide a compensatory survival pathway conferring resistance to EGFR TKIs. We have designed a bispecific EGFR-cMet antibody (JNJ-61186372) with a unique set of mechanisms of action resulting in anti-tumor activity in the EGFR mutant setting, with or without cMet pathway activation. We have demonstrated three mechanisms of action that contribute to the activity of JNJ-61186372: 1) inhibition of ligand-induced phosphorylation of both EGFR and cMet, 2) receptor degradation in vivo, and 3) enhanced ADCC activity. JNJ-61186372 inhibited EGF-induced phosphorylation of EGFR in cell lines with either wild-type (WT) EGFR or activating mutations in EGFR. In the same cell lines, JNJ-61186372 inhibited HGF-induced phosphorylation of cMet. JNJ-61186372 also blocked pERK and pAkt with similar IC50 values in EGFR-WT and EGFR mutant cell lines, indicating that downstream signaling pathways were inhibited. Total protein levels of both EGFR and cMet were decreased in xenograft tumor models following treatment with JNJ-61186372 compared to tumors from mice treated with PBS control suggesting that one mechanism by which JNJ-61186372 suppresses EGFR and cMet activity in vivo is through degradation of both receptors. The third mechanism of action is directing immune cells to kill tumor cells. JNJ-61186372 is produced with low levels of fucosylation, which translates to an enhanced antibody-dependent cellular cytotoxicity (ADCC). These three mechanisms of action of JNJ-61186372 provide a distinct preclinical profile for targeting both EGFR and cMET in a single bispecific antibody. JNJ-61186372 demonstrated efficacy in multiple in vivo tumor models with EGFR mutations, including both cell line and patient-derived xenografts. Importantly, JNJ-61186372 effectively inhibited tumor growth in models with mutant EGFR and cMet activation, whereas single agent EGFR inhibitors were less effective. The preclinical data support the clinical development of JNJ-61186372 in patients with lung cancer and other malignancies associated with aberrant EGFR and cMET signaling. Citation Format: Sheri L. Moores, Mark Chiu, Barbara Bushey, Kristen Chevalier, Peter Haytko, Joost Neijssen, Paul Parren, Janine Schuurman, Mark Anderson, Ricardo Attar, Robert Kramer, Matthew V. Lorenzi. Discovery and preclinical pharmacology of JNJ-61186372: A novel bispecific antibody targeting EGFR and cMET. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr DDT01-03. doi:10.1158/1538-7445.AM2014-DDT01-03