Study of Vidaza (Azacitidine) Versus Support Treatment in Patients With Low Risk Myelodysplastic Syndrome (Low and Intermediate-1 IPSS) Without the 5q Deletion and Transfusion Dependent Anaemia

Inclusion Criteria: 1. Patients over 18 years of age. 2. Patients who agree to take part in the study must understand the informed consent and sign it voluntarily. 3. Patients must be able to comply with all the programmed visits and other study requirements. 4. Patients with low risk International Prognostic Scoring System (IPSS 0 or Int-1) myelodysplastic syndrome (MDS) without chromosome 5 (5q) deletion and anaemia with transfusion needs. Transfusion dependence is defined as at least 2 units of erythrocyte concentrate (EC) during the 8 weeks prior to inclusion in the study, and symptomatic anaemia, defined by a haemoglobin value ≤9.0 gr/dl. 5. Patients who have not responded to previous treatment with erythropoietin (EPO): With a response profile based on basal erythropoietin (EPO) levels of \> 250 u/L, with no response alter 12 weeks of treatment at maximum doses (60.000 U or 250 µg darbepoetin (DAB), in combination with Granulocyte colony-stimulating factor (G-CSF) in cases of refractory anaemia with ringed sideroblasts (RARS)) , or with loss of the response obtained after an initial optimum response. 6. Patients who are not candidates for intensive chemotherapy and transplant modalities. 7. Patients with an Eastern Cooperative Oncology Group (ECOG) score ≤ 3 8. Women of child-bearing age and heterosexual men whose partner is of child-bearing age, must undertake to use an effective contraceptive method for the duration of the treatment and for at least 3 months alter is has finalised. Exclusion Criteria: 1. The presence of a psychiatric or medical disease which prevents the patient from signing of the informed consent. 2. Human immunodeficiency virus (HIV) Seropositive, hepatitis B antigen (AgVHB) positive or hepatitis C virus (HCV) polymerase chain reaction (PCR) positive. 3. Pregnant or nursing women. 4. Uncontrolled intercurrent disease: Active infection requiring parenteral antibiotics, Symptomatic chronic heart failure (New York Heart Association (NYHA) class III or IV), Instable angina pectoris, or Another neoplasia apart from his myelodysplastic syndromes (MDS). 5. Have been treated with demethylating drugs at any moment prior to inclusion in the study.