DNA-hypomethylating agents are a viable treatment option for AML/myelodysplastic syndrome (MDS) relapse after allograft by upregulating Ags on blasts before DLI. Seventy-two patients with relapsed AML (n=62), MDS (n=8) and other myeloid neoplasms (n=2) after allograft were treated with low-dose 5-azacytidine and, if feasible, DLI.
Patient characteristics: median age 62 years (range 20-75), 42% with adverse cytogenetics, 82% not in remission at transplant and 83% received fludarabine-based reduced-toxicity conditioning. Median duration from transplant to 5-azacytidine was 289 days (range 59-2133). Response criteria: CR, temporary disease control or treatment failure. A median of 2.7 courses (range 1-10) were administered; 65 out of 72 patients also received DLI (41 already before 5-azacytidine). Ten patients developed acute GVHD and two succumbed to treatment-related sepsis. CR rate was 9.7% (in two patients lasting >5 years), 44% had temporary disease control (median duration 71 days, range 31-380). Median survival from 5-azacytidine was 108 days, 21 patients proceeded to subsequent transplant. In multivariate analysis, peripheral blood blasts <1% were predictive of longer OS (P=0.03). Taken together, long-term remissions can be induced by this well-tolerated outpatient treatment, particularly in patients without peripheral blood blasts.