Inclusion Criteria:

- MDS with int 2 or high IPSS score eitherRAEB 1 or 2 according to the WHO
classification (see appendix 1) or CMML with WBC < 13 109/l RAEB-T according to the
FAB classification (see appendix 1) without t(8 ;21), inv 16 or t(16;16) AML
secondary to MDS (sAML) with a confirmed MDS phase of at least 2 months with
available bone marrow cytogenetics at diagnosis of AML

AND

in CR or PR according to IWG criteria (see appendix 3) after one or two courses of
predefined intensive chemotherapy (see page 12) with available cytogenetics at evaluation
of response Aged 18 years of age or more Written Informed consent Adequate Contraception,
if relevant Negative pregnancy test if relevant. Patients not eligible for the
azacitidine confirmatory trial (azacitidine " versus " conventional treatment ") or
unwilling to participate to it

Exclusion Criteria:

- AML secondary to myeloproliferative or MDS/MPD WHO subgroups except CMML with WBC< 13
109/l

- Therapy related MDS (after chemo or radiotherapy for a previous neoplasm or immune
disorder)

- Patients eligible for allogeneic bone marrow transplantation (with a identified
donor)

- Liver and/or kidney failures prohibiting the use of azacitidine. Creatininemia > 1.5
normal value ALAT and ASAT > 3N

- Bilirubin > 2 N, unless due to dyserythropoiesis

- Known hypersensitivity to azacitidine or mannitol

- Other tumor, unstable for the last three years, except in situ uterine carcinoma or
basal skin tumor

- Uncontrolled infection,

- WHO Performance status > 2

- Life expectancy less than 3 months