VIDAZA is a nucleoside metabolic inhibitor indicated for the treatment of patients with the following FAB myelodysplastic syndrome (MDS) subtypes: Refractory anemia (RA) or refractory anemia with ringed sideroblasts (RARS) (if accompanied by neutropenia or thrombocytopenia or requiring transfusions), refractory anemia with excess blasts (RAEB), refractory anemia with excess blasts in transformation (RAEB-T), and chronic myelomonocytic leukemia (CMMoL).
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Refractory anemias -- A severe sometimes chronic anemia, usually macrocytic in type, that does not respond to ordinary antianemic therapy.
Refractory anemia with ringed sideroblasts -- A myelodysplastic syndrome characterized by an anemia in which 15% or more of the erythroid precursors are ringed sideroblasts. The ring sideroblast is an erythroid precursor in which one third or more of the nucleus is encircled by granules which are positive for iron stain. It occurs primarily in older individuals. The median survival exceeds 5 years. (WHO, 2001)
Neutropenia -- A decrease in the number of neutrophilic leukocytes in the blood. (Dorland, 27th ed)
Thrombocytopenia -- A subnormal level of BLOOD PLATELETS.
Refractory anaemia with excess blasts -- Chronic refractory anemia with granulocytopenia, and/or thrombocytopenia. Myeloblasts and progranulocytes constitute 5 to 40 percent of the nucleated marrow cells.
refractory anemia with excess blasts in transformation -- Refractory anemia with excess blasts in transformation (RAEB-T) is characterised by dysplastic features of the myeloid and usually erythroid progenitor cells in the bone marrow and an increased number of myeloblasts in the peripheral blood. The peripheral blood blast count ranges from 20% to 30%. RAEB-T used to be a subcategory of myelodysplastic syndromes in the past. Recently, the term has been eliminated from the WHO based classification of myelodysplastic syndromes. The reason is that the percentage of peripheral blood blasts required for the diagnosis of acute myeloid leukemia has been reduced to 20%. The elimination of the RAEB-T term by the WHO experts has created confusion and ongoing arguments. Currently, according to WHO classification, the vast majority of RAEB-T cases are best classified as acute leukemias (acute leukemias with multilineage dysplasia following myelodysplastic syndrome). A minority of cases are part of RAEB-2.
Chronic Myelomonocytic Leukemia-1 --
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