Preclinical work has provided evidence that KRAS-mutant tumor cells are inherently resistant to MEK inhibitors secondary to RAF-mediated MEK activation, hence providing a rationale for the simultaneous inhibition of mutant KRAS and MEK.250,251 The CodeBreaK 101 trial evaluated trametinib in combination with sotorasib, with or without panitumumab, in patients with various KRASG12C-mutant solid tumors (NCT04185883). This evidence concerns the gene KRAS and neoplasm.