Cumulative incidence or relapse and clonal evolution. In the refractory study (left panels), the rate of relapse was comparable between arms (A), whereas the rate of clonal evolution (C) was higher with rabbit ATG (red) compared with alemtuzumab (blue), but this difference was not statistically significant. In the relapsed study (right panels), the rate of a second relapse after alemtuzumab was 23% (B) and the clonal evolution rate 11% (D). For the relapse study panels, dotted lines represent 95% CI.