ENEST1st was a phase 3b, multicenter, single-arm, open-label study investigating the efficacy and safety of nilotinib 300 mg twice daily (the recommended starting dose for patients with newly diagnosed CML-CP1) in a large population of patients with newly diagnosed Ph+ or Ph− BCR-ABL1+ CML-CP. Here, ABL1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.