Nilotinib versus imatinib for the treatment of patients with newly diagnosed chronic phase, Philadelphia chromosome-positive, chronic myeloid leukaemia: 24-month minimum follow-up of the phase 3 randomised ENESTnd trial

BackgroundNilotinib has shown greater efficacy than imatinib in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukaemia (CML) in chronic phase after a minimum follow-up of 12 months. We present data from the Evaluating Nilotinib Efficacy and Safety in clinical Trials-newly diagnosed patients (ENESTnd) study after a minimum follow-up of 24 months.MethodsENESTnd was a phase 3, multicentre, open-label, randomised study. Adult patients were eligible if they had been diagnosed with chronic phase, Philadelphia chromosome-positive CML within the previous 6 months. Patients were randomly assigned (1:1:1) to receive nilotinib 300 mg twice a day, nilotinib 400 mg twice a day, or imatinib 400 mg once a day, all administered orally, by use of a computer-generated randomisation schedule, using permuted blocks, and stratified according to Sokal score. Efficacy results are reported for the intention-to-treat population. The primary endpoint was major molecular response at 12 months, defined as BCR-ABL transcript levels on the International Scale (BCR-ABL(IS)) of 0·1% or less by real-time quantitative PCR in peripheral blood. This study is registered with ClinicalTrials.gov, number NCT00471497.Findings282 patients were randomly assigned to receive nilotinib 300 mg twice daily, 281 to receive nilotinib 400 mg twice daily, and 283 to receive imatinib. By 24 months, significantly more patients had a major molecular response with nilotinib than with imatinib (201 [71%] with nilotinib 300 mg twice daily, 187 [67%] with nilotinib 400 mg twice daily, and 124 [44%] with imatinib; pInterpretationNilotinib continues to show better efficacy than imatinib for the treatment of patients with newly diagnosed CML in chronic phase. These results support nilotinib as a first-line treatment option for patients with newly diagnosed disease.FundingNovartis.Hagop M Kantarjian, Andreas Hochhaus, Giuseppe Saglio, Carmino De Souza, Ian W Flinn, Leif Stenke, Yeow-Tee Goh, Gianantonio Rosti, Hirohisa Nakamae, Neil J Gallagher, Albert Hoenekopp, Rick E Blakesley, Richard A Larson, Timothy P Hughe