Inclusion Criteria:  Patients aged 18 years old or more.  Confirmed diagnosis of R/R AML, defined as:  AML refractory to 1 or 2 intensive chemotherapy courses or a treatment by hypomethylating agents (HMAs)  Or AML in first hematologic relapse or progression after front-line therapy, including intensive chemotherapy or hypomethylating agents (HMAs).  Previous treatments with FLT3 inhibitors (other than gilteritinib) are allowed R/R AML secondary to a prior chemotherapy or radiotherapy for another cancer (tAML) could be included. Presence of a FLT3-ITD mutation (allelic ratio ≥0.05 at last evaluation)* or a FLT3 TKD mutation. ECOG performance status ≤2. AST and ALT ≤ 2.5 x upper the limit of normal (ULN) and/or total and direct serum bilirubin ≤ 1.5 x ULN unless considered due to leukemia. Estimated glomerular filtration rate (GFR) ≥ 50 mL/min according to the formula usually used by the investigator. Written informed consent obtained prior to any screening procedures. Eligible for National Health Insurance in France.  Exclusion Criteria:  Acute promyelocytic leukemia or AML with BCR-ABL1 gene fusion. AML with a prior history of MDS or MPN including CMML (sAML). Patient ineligible for an intensive chemotherapy. Proven central nervous system leukemic involvement. Prior allogeneic HSCT within the last 6 months and/or history of acute GVHD of grade >1 Prior treatment with gemtuzumab ozogamicin within the last 3 months preceding the initiation of the treatment in the present clinical trial. Uncontrolled or active malignant disease within prior 12 months (excluding cutaneous basal cell carcinoma, "in-situ" carcinoma of the cervix or breast, or other local malignancy excised).  Uncontrolled or significant cardiovascular history or symptoms including:  Prior anthracycline exposure equivalent to more than 550 mg/m2 of daunorubicin History of clinically relevant ventricular arrhythmias (e.g. ventricular tachycardia, ventricular fibrillation or torsade de pointes) History of 2° (Mobitz II) or 3° heart block (subjects with pacemakers are allowed if they have no history of clinically relevant arrhythmias with the pacemaker) History of uncontrolled angina pectoris or MI within 6 months History of NYHA Class 3 or 4 heart failure Left ventricular ejection fraction ≤ 50% or less than the institutional lower limit of normal History of complete left bundle branch block Unstable angina, New York Heart Association (NYHA) class 3 or 4 congestive heart failure QTcF > or equal to 450 msec, long QT syndrome (including family history) Bradycardia < 50 bpm (unless subject has a pacemaker) Systolic BP ≥ 180 mmHg or diastolic BP ≥ 110 mmHg Uncontrolled systemic fungal, bacterial, or viral infection (defined as ongoing signs/symptoms related to the infection without improvement despite appropriate treatment). Active known HBV or HCV hepatitis or positive HIV serology. Concurrent therapy with any other investigational agent or cytotoxic drug, within 28 days before starting treatment. Only hydroxyurea ± dexamethasone is permitted for the control of blood counts. Current use or anticipated requirement for drugs that are known strong inducers of CYP3 A4/5. Current use or anticipated requirement for drugs that are known as strong inhibitors or inducers of P glycoprotein (P-gp), as mentioned in the appendix 14 of the protocol, with the exception of drugs that are considered absolutely essential for the care of the subject. Current use or anticipated treatment with concomitant drugs that target 5HT1R or 5HT2BR receptors or sigma non-specific receptor, as mentioned in the appendix 15 of the protocol, with exception of drugs that are considered absolutely essential for the care of the subject. Known malabsorption syndrome or other condition that may significantly impair absorption of oral study medications. Any of concurrent severe and/or uncontrolled medical condition, which could compromise participation in the study. Females who are pregnant or breastfeeding. Male and female subjects of childbearing potential and at risk for pregnancy must agree to use at least one highly effective method of contraception throughout the study and for 180 days after the last dose of study medication or cytarabine, whichever occurs later. Adults subject to a legal protection order or unable to give their consent. Persons deprived of their freedom by judicial or administrative decision, persons hospitalized without their consent by virtue of articles L. 3212-1 and L. 3213-1 and who are not subject to the provisions of article L. 1121-8.