Grade 3/4 toxicities by course, with mean grade and test for differences using the Wilcoxon rank-sum test. (A) LDAC vs vosaroxin course 1; (B) LDAC vs vosaroxin course 2; (C) LDAC vs LDAC + vosaroxin course 1; and (D) LDAC vs LDAC + vosaroxin course 2. ALT, alanine transaminase; AST, aspartate transaminase; vosa, vosaroxin.