LSN3074753

LSN3074753 is an experimental small molecule pan-RAF inhibitor developed by Eli Lilly. As an analog of LY3009120, it is designed to inhibit all three RAF isoforms (ARAF, BRAF, and CRAF), effectively blocking the MAPK/ERK signaling pathway. Preclinical studies, including patient-derived xenograft (PDX) trials, have shown that LSN3074753 has activity against colorectal cancer models with KRAS or BRAF mutations, particularly when used in combination with EGFR inhibitors like cetuximab. It also demonstrates sensitivity against uncommon lung cancer-specific BRAF mutations, suggesting potential utility in treating a broader range of RAF-driven malignancies compared to first-generation BRAF inhibitors. By inhibiting RAF dimers, LSN3074753 aims to overcome the paradoxical activation of the MAPK pathway often observed with earlier BRAF-selective inhibitors.