Decitabine

Decitabine is believed to exert its antineoplastic effects after phosphorylation and direct incorporation into DNA and inhibition of DNA methyltransferase, causing hypomethylation of DNA and cellular differentiation or apoptosis. Decitabine inhibits DNA methylation in vitro, which is achieved at concentrations that do not cause major suppression of DNA synthesis. Decitabine-induced hypomethylation in neoplastic cells may restore normal function to genes that are critical for the control of cellular differentiation and proliferation. In rapidly dividing cells, the cytotoxicity of decitabine may also be attributed to the formation of covalent adducts between DNA methyltransferase and decitabine incorporated into DNA. Non-proliferating cells are relatively insensitive to decitabine.

Three Day Regimen: Administer DACOGEN at a dose of 15 mg/m2 by continuous intravenous infusion over 3 hours repeated every 8 hours for 3 days. Repeat cycles every 6 weeks upon hematologic recovery (ANC at least 1,000/µL and platelets at least 50,000/µL) for a minimum of 4 cycles. . A complete or partial response may take longer than 4 cycles. Delay and reduce dose for hematologic toxicity

Five Day Regimen: Administer DACOGEN at a dose of 20 mg/m2 by continuous intravenous infusion over 1 hour daily for 5 days. Delay and reduce dose for hematologic toxicity (see Dose Modifications for Toxicity). Repeat cycles every 4 weeks upon hematologic recovery (ANC at least 1,000/µL and platelets at least 50,000/µL) for a minimum of 4 cycles. A complete or partial response may take longer than 4 cycles.

Drug interaction studies with decitabine have not been conducted. In vitro studies in human liver microsomes suggest that decitabine is unlikely to inhibit or induce cytochrome P450 enzymes. In vitro metabolism studies have suggested that decitabine is not a substrate for human liver cytochrome P450 enzymes. As plasma protein binding of decitabine is negligible (<1%), interactions due to displacement of more highly protein bound drugs from plasma proteins are not expected.

Most common adverse reactions (>50%) are neutropenia, thrombocytopenia, anemia, and pyrexia.

Based on findings from human data, animal studies, and the mechanism of action, Decitabine can cause fetal harm when administered to a pregnant woman. Advise not to breastfeed. There are no data on the presence of decitabine or its metabolites in human milk, the effects on the breastfed child, or the effects on milk production.

Neutropenia and thrombocytopenia: Perform complete blood counts and platelet counts.

Embryo-fetal Toxicity: Can cause fetal harm. Advise patients of reproductive potential of the potential risk to a fetus and to use effective contraception.

Keep below 25°C temperature, away from light & moisture. Keep out of the reach of children.