More than half of all patients with chronic myeloid leukemia in chronic phase (CML-CP) treated with nilotinib remained in treatment-free remission 48 weeks after discontinuing nilotinib therapy, according to a study presented at the 21st Congress of the European Hematology Association in Copenhagen, Denmark.1

For this single-arm, phase 2 ENESTfreedom trial, researchers evaluated the ability to stop nilotinib and maintain treatment-free remission in patients who achieved a sustained deep molecular response with first-line nilotinib.

Investigators enrolled 215 patients with CML-CP and typical b2a2 and/or b3a2 BCR-ABL1 transcripts who had received at least 2 years of frontline nilotinib and had achieved MR4.5. All participants continued nilotinib for 1 year as consolidation. Of those, 190 achieved a sustained deep molecular response during consolidation and stopped nilotinib.

At 48 weeks of treatment-free remission, 51.6% (95% CI, 44.2-58.9) of the 190 patients remained in major molecular response without renewing treatment. In addition, 47.4% (95% CI, 40.1-54.7) were in MR4.5 without reintroducing nilotinib.

Of the 86 patients who lost major molecular response and reinitiated nilotinib, 85 regained major molecular response and 76 regained MR4.5. Median time to regain major molecular response was 7.9 weeks.

RELATED: TKI Duration and Molecular Response Pivotal for Survival With Chronic Myeloid Leukemia

Myalgia, which has been reported as part of an imatinib withdrawal syndrome in previously reported studies, was observed in 24.7% of patients in treatment-free remission phase. Most of these events occurred in the first 24 weeks of treatment-free remission.                  

Reference

  1. Saglio G, Masszi T, Gomez MT, et al. Results from ENESTfreedom: Treatment-free remission (TFR) following frontline nilotinib (nil) in patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP). Paper presented at: 21st Congress of the European Hematology Association; June 2016; Copenhagen, Denmark.