LY3009120 is a pan-RAF inhibitor that is primarily used in cancer research, particularly in the study of melanoma and other cancers driven by mutations in the RAF kinase pathway. It functions by inhibiting multiple dimeric forms of RAF kinases, which helps overcome resistance seen with some selective RAF inhibitors. This makes it valuable in targeting tumors with BRAF mutations, including those resistant to first-generation inhibitors. It has shown potential in preclinical studies for suppressing tumor growth in both BRAF V600E and non-V600E mutant cancers. Due to its ability to block paradoxical MAPK pathway activation, LY3009120 is also explored in combination therapies with MEK inhibitors to enhance antitumor efficacy and reduce drug resistance. Its application extends to laboratory research for understanding RAF signaling dynamics and evaluating new strategies for treating RAS/RAF pathway-aberrant cancers.