18 Months Follow-Up of Deep Molecular Response 4.5 (MR4.5) with Nilotinib in Patients with Newly Diagnosed Chronic-Phase Chronic Myeloid Leukemia: A Prospective, Multi-Center Study in China

Early stable deep molecular response (DMR) of nilotinib is associated with goal of treatment-free remission (TFR) for patients with chronic-phase chronic myeloid leukemia (CML-CP). It is significant to early distinguish patients who can obtain DMR and fit for TFR. We performed a multicenter study to explore early cumulative MR4.5 rate by 18 months with nilotinib in patients with newly diagnosed CML-CP (ND-CML-CP) in China. From 29 institutes, 106 ND-CML-CP patients received nilotinib (300mg BID). The cumulative MR4.5 rate of nilotinib by 18 months was 69.8% (74/106). The cumulative MMR and MR4.0 rates of nilotinib by 18 months were 94.3% (100/106) and 84.9% (90/106), respectively. Patients with ultra-early molecular response (u-EMR) at 6 weeks were not significantly different to obtain DMR or MMR by 24 months compared to those without u-EMR (P=0.7584, P=0.9543, respectively). Our study demonstrated that treatment with nilotinib in patients with ND-CML-CP contributed to obtain high early MR4.5.