Relapse free survival after 1st course of vemurafenib. (A) RFS after the first course of vemurafenib. A total of 21 out of 31 responders (68%) experienced a relapse after the initial course of vemurafenib with a median RFS of 19 months (95% CI, 12.5-53.9 months). (B) Landmark analysis of RFS in patients who achieved CR vs PR at 3 months. The median RFS was 18.5 months (95% CI, 12.4 months to not reached) for those who achieved CR vs 23.9 months (95% CI, 14.9 months to not reached) for those who demonstrated PR. This was not significantly different (P = .71).