4-Year Outcome Of 215 Patients With Newly Diagnosed Chronic Myeloid Leukemia (CML) Treated Frontline With Nilotinib In Investigator-Sponsored Studies. A Report From The Gimema CML Working Party

Nilotinib is a potent and selective BCR-ABL inhibitor approved for the frontline treatment of CML. The latest update (4-yr follow-up) of the ENESTnd study demonstrated sustained superiority of nilotinib vs. imatinib (Hochhaus et al, EHA 2013, abstract 712). The CML Italian Registry of Nilotinib is the largest series of patients treated frontline with nilotinib-based regimens, outside of Company-sponsored trials. Therefore, it represents an important resource for an independent evaluation of the outcome of such patients.to analyze the response rates and outcome in an independent cohort of patients treated frontline with nilotinib-based regimens in Italy.The CML Italian Registry of Nilotinib includes 215 patients, enrolled in 2 multicenter phase II studies conducted by the GIMEMA CML WP (ClinicalTrials.gov. NCT00481052 and NCT00769327) with nilotinib 300 mg or 400 mg BID as initial treatment; 123 patients received a sequential treatment with nilotinib and imatinib, with a 3-mo rotation period. The median age was 53 years (range 18–86). Ten out of 215 patients (5%) had a high EUTOS score. The median follow-up was 43 months (range 18–69 months). We analyzed: the rates of Complete Cytogenetic Response (CCyR) and Major Molecular Response (MMR); the overall survival (OS; any death included), progression-free survival (PFS; progression to accelerated/blast phase [AP/BP] and deaths for any cause), failure-free survival (FFS; failures according to ELN 2013 recommendations and deaths for any cause), and event-free survival (EFS; events: failures, permanent discontinuation of nilotinib for any cause, including deaths).Rates of CCyR were 72% and 92% by 3 months and 12 months, respectively. Rates of MMR were 56% and 83% by 3 months and 12 months, respectively. The cumulative rates of CCyR and MMR were 93% and 92%, respectively. Overall, events were recorded in 64 (30%) patients: 31 (14%) patients permanently discontinued nilotinib for adverse events or intolerance; 22 (10%) patients failed therapy according to ELN 2013 recommendations, including 8 (3.7%) patients that progressed to AP/BP; 11 (5%) patients permanently discontinued nilotinib for other reasons. All progressions to AP/BP occurred within the first year of therapy, and all patients subsequently died. Nilotinib-resistant mutations were identified in 5 of these patients (4 T315I; 1 Y253H). No difference in the rate of progression to AP/BP was observed between patients receiving nilotinib alone or nilotinib and imatinib in sequential schedule. Overall, 15 (7%) patients died, in 7 cases for reasons unrelated to CML progression. The 4-year OS, PFS, FFS, and EFS were 93%, 93%, 86%, and 69%, respectively.These Italian nilotinib registry data provide an independent and unbiased overview of the therapeutic effects of nilotinib, with high and early rates of complete cytogenetic and major molecular response. All progressions (3.7%) to AP or BP occurred within the 1st year of therapy; however, all cases were fatal, emphasizing how crucial is the prevention of AP/BP. With a median follow-up of 43 months, 69% of patients were still on nilotinib, and 93% were alive and progression-free.European LeukemiaNet, COFIN, Bologna University, BolognAILGugliotta: Novartis: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria. Castagnetti:Novartis: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria. Bocchia:Novartis and Bristol Mayer Squibb: Honoraria. Soverini:Novartis: Consultancy; Bristol-Myers Squibb: Consultancy; ARIAD: Consultancy. Saglio:Novartis: Consultancy, Honoraria; Bristol Myers Squibb: Consultancy, Honoraria; ARIAD: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Cavo:Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Millennium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Onyx: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees. Baccarani:Novartis: Honoraria, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Speakers Bureau; Pfizer: Honoraria; Ariad: Honoraria. Rosti:Novartis: Consultancy, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Speakers Bureau; Ariad: Consultancy; Roche: Speakers Bureau.