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About Vidaza

In May 2004, Vidaza became the first drug approved by the FDA for the treatment of patients with Myelodysplastic Syndromes (MDS). The FDA approved Vidaza, the first in a new class of drugs called demethylation agents, for treatment of all five MDS subtypes. These subtypes include: 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 (CMML).

Vidaza is believed to exert its antineoplastic effects by causing hypomethylation of DNA and direct cytotoxicity on abnormal hematopoietic cells in the bone marrow. The concentration of Vidaza required for maximum inhibition of DNA methylation in vitro does not cause major suppression of DNA synthesis. Hypomethylation may restore normal function to genes that are critical for differentiation and proliferation. The cytotoxic effects of Vidaza cause the death of rapidly dividing cells, including cancer cells that are no longer responsive to normal growth control mechanisms. Non- proliferating cells are relatively insensitive to Vidaza. Vidaza was approved for IV administration in January 2007.

About Epigenetics

Azacitidine is the first of a new class of anti-cancer compounds called epigenetic therapies. DNA methylation and histone deacetylation are two of the more studied epigenetic regulators of gene expression. Epigenetics refers to changes in the regulation of gene expression. Epigenetic changes can silence gene expression and, unlike DNA mutations, may be reversed by targeting the enzymes involved. The silencing of key cell cycle control genes and tumor suppressor genes through these two mechanisms of epigenetic regulation has been demonstrated in vitro and in vivo in h
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