Randomized Study Of Decitabine Versus Conventional Care (Cc) In Patients (Pts) With Intermediate- And High-Risk Acute Myeloid Leukemia (Aml) In First Or Subsequent Complete Remission (Cr).

6527 Background: Maintenance therapy in AML is not standard. Methylation of tumor suppressor genes in CR predicts relapse. Hypomethylating therapy may be effective in maintaining CR. Methods: We compared DAC to conventional care (CC, low dose subcutaneous ara-C, prolonged chemotherapy, or observation) in pts with AML in first (CR1) or subsequent CR (CR>1). Pts with non-favorable risk AML received induction and consolidation, were stratified by age (≤ 60 vs. > 60) and cytogenetics (CG; intermediate vs. poor risk), and randomized to DAC 20 mg/m2 IV daily x 5 every 4 to 8 wks for 12 cycles, or CC. Pts in CR>1 were randomized after salvage. Primary endpoint was no relapse at 1 year. MRD was monitored by multicolor flow cytometry (MFC) by custom staining panels based on the phenotypes in BM. Serial samples for methylation studies were collected. Results: 50 pts have been enrolled; 41 (17 M, 24 F) pts (including 32 in CR1 and 9 in CR>1) were evaluable. Median age is 57 yrs (range, 24-77). 28 pts are ≤ 60 yrs. CG at diagnosis was intermediate in 37 pts, poor-risk in 3 pts, and favorable [inv(16)] in one relapsed patient. 19 evaluable pts were randomized to DAC and have received a median of 4 cycles (range 1-12). 22 evaluable pts were randomized to CC. With a median duration of follow up for the entire group of 69 wks (range, 12-159 wks); 7 of 19 (36.8%) on DAC versus 14 of 22 (63.6%) on CC are alive in CR (p = 0.02). Toxicity in the DAC arm was reversible G 3/4 neutropenia (13), G 3/4 thrombocytopenia (9), and G 2 anemia (1). Other G 3/4 adverse events on the DAC arm include hypertension (1), fatigue (1) and line related infection (1). No treatment-related deaths on the study. MRD assays by MFC were done on BM in 39 pts. MRD was detected in 11 pts, involving 0.04% to 1% (mean 0.5%) of total cells; 9 pts subsequently relapsed 1.5 to 10 mths after first positive MFC; the other 2 died within 2 mths from other causes. MRD was detected in 9 of 19 (47%) pts who relapsed. In 18 pts remaining in CR, no MRD was identified. Conclusions: DAC in CR is well tolerated. MFC can predict relapse in CR. Higher incidence of relapse in the DAC arm may be due to different patterns of methylation and response to DAC in younger AML pts. Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Eisai, MGI Pharma Eisai Eisai, MGI Pharma