Fc-mediated mechanism of action for the novel EGFR-cMET bispecific antibody (JNJ-61186372) in non-small cell lung cancer

JNJ-61186372 (JNJ-372) is an anti-EGFR and cMet bispecific antibody with an active Fc backbone (IgG1) designed to treat non-small cell lung cancer (NSCLC) disease. A first-in-human study is currently being conducted to assess the safety and preliminary efficacy of JNJ-372 in patients with advanced NSCLC. Early data suggests that JNJ-372 can induce partial responses in subjects with diverse populations of EGFR-mutated NSCLC, including Exon 20ins as well as TKI resistance mutations. Our previous pre-clinical in vivo studies showed that the Fc inactive version (IgG2sigma) of the EGFR/cMet antibody was significantly impaired in its ability to inhibit tumor growth compared to the Fc active JNJ-372. The IgG2sigma variant also reduced the ability of the bispecific antibody to mediate downregulation of EGFR, cMet and downstream signaling components. This suggested that the interaction of the Fc arm with the Fc receptors on the innate immune cells play a crucial role in the mechanism of action of JNJ-372. While JNJ-372 has demonstrated antibody dependent cellular cytotoxicity (ADCC) and antibody dependent cellular phagocytosis (ADCP) in vitro, the potential role of Fc interactions in downregulation of EGFR and cMet was not well understood. We explored the different Fc-mediated immune effector functions of JNJ-372 and interrogated how they contribute to EGFR and cMet downregulation and overall efficacy. In NSCLC cell lines, JNJ-372 induced Fc-mediated dose-dependent ADCC and ADCP but not complement-dependent cytotoxicity. Further, the presence of isolated human immune cells (PBMC) significantly enhanced JNJ-372 mediated EGFR and cMet downregulation and dose-dependent tumor cell killing. Studies are in progress to better understand which immune cells and which Fc receptor interactions are essential for the drug efficacy through immune cell depletion and FcR blocking studies; such studies may help guide clinical biomarker development. This work elucidates a novel Fc-dependent mechanism of action for the EGFR-cMet bispecific antibody. Citation Format: Smruthi Vijayaraghavan, Barbara Bushey, Lorriane Lipfert, Rupesh Nanjunda, Eilyn R. Lacy, Peter Buckley, Sylvie Laquerre, Matthew V. Lorenzi, Sheri Moores. Fc-mediated mechanism of action for the novel EGFR-cMET bispecific antibody (JNJ-61186372) in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4818.