Inclusion Criteria:

Screening:

- signed informed consent

- Age ≥18 years

- patients with MDS or AML after conventional chemotherapy or allogeneic HSCT and
positive molecular marker such as t(8,21), inv16, t(6,9), NPM1 pos. or CD34+ in the
case of an allogeneic HSCT

Treatment:

- MDS or AML without haematological relapse (blasts <5% in the bone marrow), and

- decrease of CD34 donor chimerism (<80%) after allogeneic related or unrelated HSCT in
CD34+ MDS or AML or

- increase in the AML-specific molecular marker in the quantitative PCR for t(8,21),
inv16, t(6,9), NPM1+ AML >1% after conventional chemotherapy or allogeneic HSCT or

- persistence of the (above) MRD levels >1% (relative to the reference gene) after
conventional chemotherapy or allogeneic HSCT

- leukocytes > 3 Gpt/l and platelets >75 Gpt/l (transfusion independent)

Exclusion Criteria:

- Known history of hypersensitivity to any of the drugs used or their constituents or
to drugs with similar chemical structure,

- Participation of the patient in another clinical trial within the last 4 weeks before
the inclusion

- addiction or other disorders that do not allow the concerned person, to assess the
nature and scope and possible consequences in the clinical investigation

- pregnant or breast feeding women

- women of childbearing potential, except women who meet the following criteria:

- post-menopausal (12 months natural amenorrhea or 6 months amenorrhea with serum
FSH >40 U/ml)

- postoperative (6 weeks after bilateral ovariectomy with or without hysterectomy)

- regular and proper use of a contraceptive method with error rate <1% per year
(e.g., implants, depot injections, oral contraceptives, intrauterine device,
IUD)

- sexual abstinence

- Vasectomy of the partner

- Men who do not use one of the following types of contraception for a period of 3
months after completion of therapy:

- sexual abstinence

- State post-vasectomy

- Condom

- Evidence that the participating person is not expected to comply with the protocol
(such as lack of cooperation)

- Uncontrolled active infection

- Severe hepatic impairment (AST and ALT may not exceed three times the normal) or
liver cirrhosis or malignant liver tumor

- Dialysis dependent renal dysfunction

- Known severe congestive heart failure, incidence of clinically unstable cardiac or
pulmonary disease These criteria are not for the screening phase up to a known
allergic reaction to azacitidine or intolerance to apply.