Daily treatment with PD0325901 at doses of 5 and 25 mg kg−1 completely suppressed the growth of SKMEL28 and Colo205 BRAF(V600E) mutant xenografts (Fig. 4a and Supplementary Fig. S3; P < 0.01 for both 5 and 25 mg kg−1 versus control, P = 0.16 for 5 versus 25 mg kg−1).