Abstract B27: Improved survival with erdafitinib (JNJ-42756493) and PD-1 blockade mediated by enhancement of anti-tumor immunity in an FGFR2-driven genetically engineered mouse model of lung cancer (2017)

Abstract Targeted therapies against activated oncogenes, such as receptor tyrosine kinases, have significantly prolonged non-small cell lung cancer (NSCLC) patient survival, but the development of resistance limits the durability of clinical response. Genetic alterations which constitutively activate Fibroblast Growth Factor Receptors (FGFR) have been observed in patients with NSCLC. Erdafitinib (JNJ-42756493), an orally bioavailable pan-FGFR inhibitor discovered as part of a collaboration between Janssen and Astex Pharmaceuticals, has been shown to inhibit FGFR signaling pathways resulting in cell death and tumor growth inhibition in both in vitro and in vivo models of FGFR pathway aberration. Further, erdafitinib has been shown to have favorable pharmaceutical properties with manageable side effects in humans and several clinical trials are currently underway. One potential strategy to enhance the durability of response to targeted therapies, such as FGFR inhibitors, is to couple them with immunotherapy. In this setting, T cell responses primed and activated by increased antigen release resulting from the tumor cell targeted therapy could be enhanced and maintained by T-cell directed checkpoint blockade. To test this hypothesis, we evaluated erdafitinib in combination with an anti-programmed death-1 (PD-1) blocking antibody in an autochthonous FGFR2K660N/p53 genetically engineered mouse model (GEMM) of lung cancer, in which tumors develop within the context of an intact immune microenvironment. Cohorts of tumor bearing FGFR2K660N/p53 mutant mice treated with erdafitinib with or without anti-PD-1 showed significant tumor regressions compared to control and anti-PD-1 alone groups. Despite lack of differences in acute tumor responses between erdafitinib monotherapy and combination therapy, we observed significant survival benefit in the combination group erdafitinib alone (median survival 19.7 weeks vs 13.4 weeks, p&amp;lt;0.004). In a separate study, similar tumor regressions were noted in the FGFR-driven GEMM at 1 week of erdafitinib with or without anti-PD-1 treatment, while no such response to these treatments was noted in a KRAS-driven lung cancer GEMM. Immune profiling of tumor specimens revealed high baseline expression of programmed death ligand-1 (PD-L1) expression by IHC and flow cytometry. Following combination treatment, subsequent immunohistochemistry (IHC) analyses showed a significant decrease in Ki67 and PD-L1 positive tumor cells, accompanied by an increase in cluster of differentiation 3 (CD3) positive tumor-infiltrating cells in combination group as compared to control. T cell function is not inhibited by erdafitinib, as measured in vitro by mixed lymphocyte reaction and cytomegalovirus recall assays. Additional changes observed in lung tumors across treatment groups in immune cell infiltration, functionality, and T-cell clonality will be discussed. These data suggest that combination treatment of erdafitinib and PD-1 blockade drives improved survival in FGFR2-driven model of lung cancer by simultaneous inhibition of FGFR pathway in tumor cells and enhancement of anti-tumor immunity. Thus, data here provide rationale for the combined clinical testing of erdafitinib and PD-1 blockade in patients with FGFR-altered lung cancers. Citation Format: Sangeetha Palakurthi, Mari Kuraguchi, Sima Zacharek, Jeff Liu, Dennis Bonal, Wei Huang, Kristin Depeaux, Abha Dhaneshwar, Sam Regan, Dyane Bailey, Martha Gowaski, Mei Zheng, Roderick Bronson, Catherine Ferrante, Enrique Zudaire, Sylvie Laquerre, Mark Bittinger, Kirschmeier Paul, Kathryn Packman, Raluca I. Verona, Kwok-Kin Wong, Matthew V. Lorenzi. Improved survival with erdafitinib (JNJ-42756493) and PD-1 blockade mediated by enhancement of anti-tumor immunity in an FGFR2-driven genetically engineered mouse model of lung cancer. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr B27.