Efficacy and Safety of Front-Line Nilotinib Treatment and Discontinuation in Older Patients (≥65 years) with Chronic Myeloid Leukemia in Chronic Phase Who Have Achieved MR4.5: Results from ENESTfreedom

Background: Data from the phase 2, single-arm ENESTfreedom study (NCT01784068) have demonstrated the feasibility of treatment-free remission (TFR) following front-line nilotinib (NIL) treatment, with substantial TFR rates being sustained over time among patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP). Results for long-term outcomes after a 5-year follow-up are presented here. The current subanalysis evaluated the efficacy and safety of TFR after upfront treatment with NIL in older (≥65 years [yrs] at study entry) vs younger ( Methods: Adult pts enrolled in ENESTfreedom had achieved MR4.5 after ≥2 years of front-line treatment with NIL. They then entered a 52-week consolidation (CONS) phase in which they continued treatment with NIL 300 mg twice-daily; pts still in MR4.5 at the end of CONS entered the TFR phase. NIL treatment was re-initiated upon loss of major molecular response (MMR). Rates of MMR and MR4.5, as well as safety, were evaluated according to age group ( Results: The total number of pts analyzed was 215, of which 171 were Disclosures García Gutiérrez: Novartis Pharma AG: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Incyte: Consultancy, Honoraria, Research Funding. Radich:Jazz: Consultancy; Amgen: Consultancy; Bristol-Myers Squibb: Consultancy; Novartis Pharmaceuticals Corporation: Consultancy, Research Funding. Hochhaus:MSD: Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Incyte: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Takeda: Honoraria. Saglio:Roche: Research Funding; Ariad: Research Funding; Incyte: Research Funding; Novartis: Research Funding; Bristol-Myers Squibb: Research Funding; Pfizer: Research Funding. Conneally:Novartis: Consultancy, Research Funding; Bristol-Myers Squibb: Honoraria; Pfizer: Honoraria; Gilead: Honoraria. le Coutre:Incyte: Honoraria; Pfizer: Honoraria; Novartis: Honoraria. Gattermann:Novartis: Honoraria, Research Funding. Saussele:Pfizer: Honoraria; Incyte: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria, Research Funding. Giles:Actuate Therapeutics Inc: Consultancy; Pfizer: Research Funding; Novartis: Consultancy, Research Funding. Aimone:Novartis: Current Employment. Li:Novartis: Current Employment. Titorenko:Novartis: Current Employment. Ross:Celgene: Research Funding; Bristol-Myers Squibb: Honoraria; Novartis: Honoraria, Other: Participated in advisory board meetings, Research Funding.