Fulzerasib (IBI351, GFH925) is an irreversible small molecule inhibitor for KRAS G12C mutation blocking KRAS pathway signaling pERK with an IC50 of 37 nM. It demonstrates potent anti-tumor activity in multiple KRAS G12C-mutant tumor models including human pancreatic cancer, human lung adenocarcinoma, colorectal adenocarcinoma, and lung cancer models.