Inclusion Criteria:

- Patients with confirmed diagnosis of acute myeloid leukemia according to the World
Health Organization (WHO) classification (including de novo AML, t-AML and s-AML)

- Presence of NPM1 mutation as assessed in one of the central AMLSG reference
laboratories.

- Age > 60 years. There is no upper age limit.

- No prior chemotherapy for leukemia except hydroxyurea to control hyperleukocytosis if
needed for up to 10 days during the diagnostic screening phase.

- Signed written informed consent

- Men must give their informed consent that they do not father a baby and must use a
latex condom during any sexual contact with women of childbearing potential, even if
they have undergone a successful vasectomy. (while on therapy and for 3 month after
the last dose of chemotherapy)

- WHO performance status ≤ 3

- Patients not eligible for intensive chemotherapy according to at least one of the
following criteria

- HCT-CI Score >2

- Patient's decision

- age ≥ 75 years

Exclusion Criteria:

The presence of any of the following will exclude a patient from study enrollment:

- All other AML subtypes, in particular those AML with other recurrent genetic changes
(according to WHO 2008):

- AML with t(8;21)(q22;q22); RUNX1-RUNX1T1

- AML with inv(16)(p13.1q22) or t(16;16)(p13.1;q22); CBFB-MYH11

- AML with t(15;17)(q22;q12); PML-RARA (or other translocations involving RARA)

- AML with t(9;11)(p22;q23); MLLT3-MLL (or other translocations involving MLL)

- AML with t(6;9)(p23;q34); DEK-NUP214

- AML with inv(3)(q21q26.2) or t(3;3)(q21;q26.2); RPN1-EVI1

- No consent for registration, storage and processing of the individual
disease-characteristics and course as well as information of the family physician and
all other treating physicians about study participation

- Bleeding disorder independent of leukemia

- Uncontrolled infection

- Known positive for HIV, HBV or HCV

- Organ insufficiency (creatinine >1.5x upper normal serum level; bilirubin, AST or ALP
>2.5x upper normal serum level, not attributable to AML; heart failure NYHA III/IV;
severe obstructive or restrictive ventilation disorder)

- Severe neurological or psychiatric disorder interfering with ability of giving an
informed consent

- Patients with a "currently active" second malignancy other than non-melanoma skin
cancers. Patients are not considered to have a "currently active" malignancy if they
have completed therapy and are considered by their physician to be at less than 30%
risk of relapse within one year.