Impact Of Treatment With Frontline Nilotinib (Nil) Vs Imatinib (Im) On Sustained Deep Molecular Response (Mr) In Patients (Pts) With Newly Diagnosed Chronic Myeloid Leukemia In Chronic Phase (Cml-Cp)

Background: For pts with CML-CP treated with frontline IM, achievement of a sustained deep MR is one of the major criteria associated with successful treatment-free remission (TFR); other factors, including long duration of IM therapy and favorable Sokal risk score, have also been shown to be important. Factors affecting successful TFR in pts treated with frontline NIL are under investigation. Ongoing studies are evaluating TFR in pts who have received different durations of TKI treatment and achieved different durations of sustained MR4 (BCR-ABL1 ≤ 0.01% on the International Scale [BCR-ABL1IS ]) or MR4.5 (BCR-ABL1IS ≤ 0.0032%). Here, 6-y data from the ENESTnd trial of frontline NIL vs IM were analyzed to evaluate rates of MR4 and MR4.5 with each agent and estimate pts' rates of sustained response for ≥ 1 y while on NIL or IM treatment.