Rineterkib hydrochloride (compound B) is an orally active RAF and ERK1 2 inhibitor in the treatment of a proliferative disease characterized by activating mutations in the MAPK pathway. The activity is particularly related to the treatment of KRAS-mutant NSCLC, BRAF-mutant NSCLC, KRAS-mutant pancreatic cancer, KRAS-mutant colorectal cancer (CRC) and KRAS-mutant ovarian cancer[1]. ERK-IN-1 (compound B) (50, 75 mg kg, p.o., qd q2d, 27 days) treatment significantly reduces the tumor volume in the Calu-6 human NSCLC subcutaneous tumor xenograft model in mice[1]. [1]. CAPONIGRO, et al. THERAPEUTIC COMBINATIONS COMPRISING A RAF INHIBITOR AND A ERK INHIBITOR. WO2018051306A1.