Approximately 10% of patient develop AML after chemotherapy or radiation for unrelated disease (t-AML) and 20% have AML with an antecedent hematologic disorder (AML-MRC). CPX-351 (Vyxeos), a liposomal formulation of a fixed molar ratio (1:5) daunorubicin and cytarabine, has been approved for treatment of adults with newly diagnosed t-AML or AML-MRC. CPX-351 significantly improved median overall survival. Although induction chemotherapy results in remission in many older patients with AML, relapse is common and overall survival is poor. For patients not eligible for HSCT, maintenance therapies are needed to reduce the risk of relapse and prolong overall survival without causing undue adverse effects or compromising health-related quality of life. Oral azacitidine (ONUREG) has been approved by FDA on September, 2020, to treat adult patients with AML who achieved CR or CRi following intensive induction chemotherapy with or without consolidation and who are not able to complete intensive curative therapy (not candidate to HSCT). The use of oral azacitidine maintenance is an integral part of clinical practice for AML patients who have achieved a first complete remission (CR) or complete remission with incomplete blood count recovery (CRi) after intensive 3+7 induction chemotherapy and who are unable to complete intensive curative therapy. But there are few data on its efficacy as a post-CPX-351 maintenance agent in patients with newly diagnosed t-AML or AML-MRC or de novo AML.THe aim of this study is to show the improvement of overall survival with use of oral Azacitidine as maintenance for patients with de novo AML including t-AML or AML-MRC who achieved complete remission or complete remission with incomplete blood count recovery after CPX-351. Long-term product safety is also being studied