COLSTAR is a randomized, open-label study comparing Fu/Mo combined with TT to TT monotherapy in RAS/BRAFwt mCRC patients previously treated with chemotherapy….Among the patients included in the study, 4 out of 7 patients had stable disease (SD) as the best overall response (BOR)....Overall, the combination of Fu/Mo with TT was well tolerated in this cohort of 7 patients and no new safety signals were observed.