ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The prospective, multicenter, Stop Imatinib (STIM) trial evaluated imatinib discontinuation for 100 patients with CML >18 years old who achieved CMR (defined as >5-log reduction in BCR–ABL and ABL levels and undetectable transcripts by quantitative RT-PCR) for at least 2 years, after ≥3 years of TKi treatment.