Background Recurrence is a major cause of treatment failure after allogeneic transplantation for AML and MDS, and treatment options are very limited. Azacitidine is a DNA methyltransferase inhibitor with activity in myeloid disease. We hypothesized that low-dose azacitidine administered after transplant would reduce relapse rates, and conducted a study to determine a safe dose/schedule combination. Methods Forty-five high-risk patients were treated. Median age was 60 years; median number of comorbidities was three; 67% were not in remission. Using a Bayesian adaptive method to determine the best dose/schedule combination based on time to toxicity, we investigated combinations of five daily azacitidine doses: 8, 16, 24, 32 and 40 mg/m2, and four schedules: 1, 2, 3 or 4 cycles, each with 5 days of drug and 25 days of rest. Cycle 1 started on day +40. Results Reversible thrombocytopenia was the dose-limiting toxicity. The optimal combination was 32 mg/m2 given for 4 cycles. Median follow-up is 20.5 months. One-year event-free and overall survival were 58% and 77%, justifying further studies to estimate long-term clinical benefit. No dose significantly affected DNA global methylation. Conclusions Azacitidine at 32 mg/m2 given for 5 days is safe and can be administered after allogeneic transplant for at least 4 cycles to heavily pre-treated AML/MDS patients. Our trial also suggested that this treatment may prolong event-free and overall survival, and that more cycles may be associated with greater benefit.

Purpose: 5-Azacytidine (5-AZA) is a DNA-hypomethylating agent. Valproic acid is a histone deacetylase inhibitor. Combining hypomethylating agents and histone deacetylase inhibitors produces synergistic anticancer activity in vitro and in vivo. On the basis of this evidence, we conducted a phase I study of the combination of 5-AZA and valproic acid in patients with advanced cancers. Experimental Design: 5-AZA was administered s.c. daily for 10 days.Valproic acid was given orally daily with a goal to titrate to plasma levels of 75 to 100 Ag/mL (therapeutic for seizures). Cycles were 28 days long. 5-AZA was started at 20 mg/m 2 and escalated using an adaptive algorithm based on the toxicity profile in the prior cohort (6 + 6 design). Peripheral blood mononuclear cell global DNA methylation and histone H3 acetylation were estimated with the long interspersed nucleotide elements pyrosequencing assay and Western blots, respectively, on days 1and 10 of each cycle when patients agreed to provide them. Results: Fifty-five patients were enrolled. Median age was 60 years (range, 12-77 years). The maximum tolerated dose was 75 mg/m 2 of 5-AZA in combination with valproic acid. Doselimiting toxicities were neutropenic fever and thrombocytopenia, which occurred at a dose of 94 mg/m 2 of 5-AZA. Stable disease lasting 4 to 12 months (median, 6 months) was observed in 14 patients (25%). A significant decrease in global DNA methylation and induction of histone acetylation were observed. Conclusion: The combination of 5-AZA and valproic acid is safe at doses up to 75 mg/m 2 for 5-AZA in patients with advanced malignancies.

The polymorphic products of major histocompatibility complex class I-related chain A (MICA) genes are important in solid organ transplantation rejection. MICA expression is limited to gut epithelium and may play a role in triggering acute graft-versus-host disease (aGVHD). A total of 236 recipients of unrelated donor transplantation were studied. Donor-recipient human leukocyte antigen (HLA) match was 10/10 human leukocyte antigen (HLA-A, -B, -C, -DRB1, -DQB1) in 73% and MICA mismatch in 8.4%. Because of physical vicinity of the loci, MICA mismatch was significantly associated with mismatch at HLA-B and HLA-C. A higher rate of grade II-IV aGVHD was seen in MICA-mismatched patients (80% vs 40%, P ‫؍‬ .003) irrespective of degree of HLA matching (HLA 10/10 match: 75% vs 39%, P ‫؍‬ .02) and HLA any mismatch (83% vs 46%, P ‫؍‬ .003). The rate of grade II-IV gastrointestinal aGVHD was also higher in MICA-mismatched patients (35% vs 17%, P ‫؍‬ .05). We conclude that MICA may represent novel a transplantation antigen recognized by human allogeneic T cells. This study was registered at ClinicalTrials.gov (Identifier NCT00506922).

BackgroundHemorrhagic cystitis is a common cause of morbidity after allogeneic stem cell transplantation, frequently associated with BK virus infection. We hypothesized that patients with positive BK viruria before unrelated or mismatched related donor allogeneic hematopoietic stem cell transplantation have a higher incidence of hemorrhagic cystitis. Design and MethodsTo test this hypothesis, we prospectively studied 209 patients (median age 49 years, range 19-71) with hematologic malignancies who received bone marrow (n=78), peripheral blood (n=108) or umbilical cord blood (n=23) allogeneic hematopoietic stem cell transplantation after myeloablative (n=110) or reduced intensity conditioning (n=99). Donors were unrelated (n=201) or haploidentical related (n=8). ResultsTwenty-five patients developed hemorrhagic cystitis. Pre-transplant BK viruria detected by quantitative PCR was positive in 96 patients. The one-year cumulative incidence of hemorrhagic cystitis was 16% in the PCR-positive group versus 9% in the PCR-negative group (P=0.1). The use of umbilical cord blood or a haploidentical donor was the only significant predictor of the incidence of hemorrhagic cystitis on univariate analysis. There was also a trend for a higher incidence after myeloablative conditioning. Multivariate analysis showed that patients who had a positive PCR pre-transplant and received haploidentical or cord blood grafts with myeloablative conditioning had a significantly higher risk of developing hemorrhagic cystitis (58%) than all other recipients (7%, P<0.001). ConclusionsHemorrhagic cystitis is the result of a complex interaction of donor type, preparative regimen intensity, and BK viruria.

The optimal pretransplant regimen for acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) in patients ≥55 years of age remains to be determined. The myeloablative reduced-toxicity 4-day regimen IV busulfan (Bu) (130 mg/m2)-IV fludarabine (Flu) (40 mg/m2) is associated with low morbidity and mortality. We analyzed 79 patients ≥55 years of age (median, 58 years) with AML (n=63) or MDS (n=16) treated with IV Bu-Flu conditioning regimens between 2001 and 2009 (median follow-up, 24 months). The patients who received this regimen had a good performance status. The 2-year overall survival rates for patients in first complete remission (CR1), second CR (CR2), refractory disease and for all patients at time of transplantation were 71%, 44%, 32%, and 46%, respectively; 2-year event-free survival rates for patients in CR1, CR2, or refractory disease at time of transplantation and for all patients were 68%, 42%, 30%, and 44%, respectively. One-year transplant-related mortality (TRM) rates for patients who were in CR or who had active disease at the time of transplantation were 19% and 20%, respectively. Grade II-IV acute graft-versus-host disease was diagnosed in 40% of the patients. Our results suggest that age alone should not be the primary reason for exclusion from receiving myeloablative reduced-toxicity conditioning with IV Bu-Flu preceding transplantation in patients with AML/MDS.