Abstract

The role of maintenance therapy in acute myeloid leukemia (AML) remains unclear. Continued therapy with cytotoxic agents similar to those used for induction and consolidation is associated with toxicity but can improve disease free survival (DFS). (

Buchner T,
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2006
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24
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and
Lowenberg B,
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1998
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) Immune modulation in this setting may also be effective in prolonging DFS.(
Brune M,
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2006
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108
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88
). Methylation status of tumor suppressor genes in clinical remission predicts the relapse risk in AML with earlier relapse in patients with increased DNA promotor methylation.(
Agrawal S,
Cancer Res
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2007
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67
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1370
) Therefore, hypomethylating therapy may be effective in maintaining remission and prolonging survival in these patients. We are conducting a clinical trial comparing decitabine to cytotoxic chemotherapy or observation in patients with AML in their first or subsequent complete remission (CR). Patients with non-favorable risk AML (including intermediate and poor risk) receive induction therapy with idarubicin and high dose cytarabine followed by at least 2 cycles of cytarabine based consolidation. They are then stratified by age (≤ 60 vs. > 60) and cytogenetics (intermediate vs. poor risk) and randomized to receive decitabine 20 mg/m2 IV daily × 5 every 4 to 8 weeks for 12 cycles, or to continue chemotherapy/observation. Patients in > first CR are randomized after completion of salvage therapy. Serial samples for methylation studies and determination of minimal residual disease by flow cytometry are collected. To date, 19 (8 M, 11 F) patients with AML (including 14 in first CR and 5 in subsequent CR) have been enrolled onto the study. Median age of the patients is 56 years (range 31 – 74). Fourteen patients are ≤ 60 years. Cytogenetics at diagnosis was intermediate in 10 patients, poor-risk in 8 patients, and favorable [inv(16)] in one relapsed patient. Eight patients were randomized to decitabine and have received a median of 3 cycles (range 1 – 6). Eleven patients were randomized to observation/continued therapy and all, except 2 patients, have received further cytarabine based therapy after consolidation. With a median duration of follow up for the entire group of 5 months (range 1 – 9), 7/8 patients on the decitabine arm and 9/11 patients on the other arm have remained in remission. Toxicity in the decitabine treated patients was limited to 4 episodes of grade 3 neutropenia, 2 episode of grade 3 thrombocytopenia, and 1 episodes of grade 3 anemia. All of these cytopenias were short in duration and reversed without any associated adverse events. We conclude that administration of decitabine in CR at the above schedule/dose is safe and well tolerated.

Author notes

Disclosure:Research Funding: MGI Pharma. Honoraria Information: MGI Pharma. Membership Information: Member of advisory committees and speakers bureau - MGI Pharma. Off Label Use: Use of decitabine in remission. Use of decitabine in acute myeloid leukemia.