Son of sevenless homolog 1 (SOS1) plays a crucial role in the conversion of KRAS from its GDP- to its GTP-bound form independently of KRAS mutational status, thus being a promising therapeutic target for all tumors driven by KRAS. Haihe Biopharma Co. Ltd. has presented a potent SOS1 inhibitor, HH-100937, that has been found effective as monotherapy or when combined with drugs targeting the KRAS/MAPK pathway.