LNG-451 causes tumor regression in both cell line-derived and patient-derived EGFR Ex20ins-dependent xenograft tumor models...LNG-451 treatments were well-tolerated and produced significant anti-tumor activities with 99.5% (2.5 mg/kg LNG-451) and 99.9% (25 mg/kg LNG-451) reductions in total bioluminescence signal (BLI) and regression of tumor BLI (2.5 mg/kg LNG-451 28.8% regression; 25 mg/kg LNG-451, 80.3% regression)...LNG-451 is a CNS-penetrant, wild-type EGFR-sparing, EGFR Ex20ins inhibitor that is expected to provide strong anti‑tumor efficacy for patients with advanced/metastatic solid cancers harboring oncogenic EGFR exon 20 insertions with reduced WT EGFR driven toxicities.