EFS and overall survival after vemurafenib treatment. EFS (time from start of vemurafenib to death or retreatment) and overall survival of patients receiving vemurafenib for HCL (n = 21). Median EFS from start of treatment was 17 months and median overall survival was not reached. Median time after cessation of vemurafenib treatment to retreatment or death was 14 months.