Patients with BCR-ABL1 values ≤10% at 3 months had significantly better outcome than patients with BCR-ABL1 values >10%. A BCR-ABL1 value >10% at 3 months is categorized as a warning or treatment failure and occurred in 97 of 528 patients. These patients had significantly inferior (A) OS, (B) PFS, (C) FFS, (D) MMR, and (E) MR^4.5 compared with patients where BCR-ABL1 was ≤10% at 3 months (n = 410).