Dexamethasone Added to Intensive Chemotherapy in Older Patients with Acute Myeloid Leukemia (AML)

Inclusion Criteria: 1. \> 60 years of age. 2. Newly diagnosed AML according to the World Health Organization (WHO) 2016 either de novo AML or therapy-related AML (i.e AML arising after previous cytotoxic therapy or radiation) 3. AML with favorable or intermediate cytogenetic risk according to Medical Research Council (MRC 2010) classification. 4. Subjects should be eligible for intensive chemotherapy by Idarubicin, cytarabine, Lomustine. 5. Eastern Cooperative Oncology Group (ECOG) performance status \< 3 (appendix 1). 6. SORROR score ≤ 3 (appendix 2). 7. Adequate baseline organ function defined by the criteria below: * Total bilirubin ≤ 1.5 x Upper Limit of Normal (ULN) unless bilirubin rise is due to Gilbert's syndrome * Alanine Aminotransferase (ALAT) and Aspartate Transaminase (ASAT) ≤ 3xULN * creatinin clearance (Cockcroft-Gault) ≥ 30 ml/min * Unless considered due to leukemic organ involvement 8. Adequate cardiac function with Left Ventricular Ejection Fraction (LVEF) ≥50% 9. Absence of any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule. 10. Women will be menopausal to be enrolled 11. The patient must give written (personally signed and dated) informed consent before completing any study-related procedure which means assessment or evaluation that would not form part of the normal medical care of the patient and before the start of induction chemotherapy. 12. Affiliated to the French Social Security (Health Insurance). Exclusion Criteria: 1. Acute promyelocytic leukemia (APL) or acute megakaryocytic leukemia (AML-FAB M7). 2. AML with adverse cytogenetic risk according to the MRC 2010 classification. 3. AML arising from myelodysplastic syndromes, myeloproliferative disorders or chronic myelo-monocytic leukemia according to WHO classification (2016). 4. AML with Philadelphia chromosome or with BCR-ABL1. 5. Known active central nervous system leukemia 6. Previous anti-AML treatment other than hydroxyurea. 7. Cumulative anthracycline dose equivalent to ≥550 mg/m². 8. Treatment with an investigational drug within 30 days or 5 half-life whichever is longer, preceding the first dose of study medication. 9. Prior history of cancer unless controlled for at least 2 years and except for basal cell carcinoma, non-melanoma skin cancer and in situ cervical carcinoma. 10. Severe medical or mental condition precluding the administration of protocol treatments 11. Any sign of active uncontrolled disease including but not restricted to cardiac disease, infections, hepatitis. 12. Any severe chronic disease potentially interfering with the protocol including HIV infection, active hepatitis B or C. 13. Any severe conditions inducing contra-indications to dexamethasone including uncontrolled diabetes, infections, hypertension, stomach ulcer, mental illness, myasthenia or glaucoma. 14. Any serious medical condition, laboratory abnormality, or psychiatric illness that would place the participant at an unacceptable risk or prevent them from giving informed consent. 15. Known active HIV, Hepatitis B or C infection. 16. Pregnancy or breastfeeding. 17. Patients who are incapacitated, under wardship, legal guardianship, or under the protection of the courts. 18. Patients under State Medical Assistance (AME).