Tunlametinib (科露平®) is an oral, selective, mitogen-activated protein kinase kinase 1 and 2 (MEK 1/2) inhibitor being developed by Shanghai KeChow Pharma, Inc. for the treatment of solid tumours with RAS and RAF mutations, including melanoma, non-small cell cancer (NSCLC), colorectal cancer (CRC) and neurofibromatosis type 1 (NF1) plexiform neurofibromas. In March 2024, tunlametinib was granted conditional approval in China (based on surrogate endpoints) for use in patients with NRAS-mutated advanced melanoma who have failed anti-PD-1/PD-L1 treatment. This article summarizes the milestones in the development of tunlametinib leading to this first approval for the treatment of solid tumours with RAS and RAF mutations.