Reduced-intensity conditioning by fludarabine/busulfan without additional irradiation or T-cell depletion leads to low non-relapse mortality in unrelated bone marrow transplantation

Pharmacokinetics of intravenous mycophenolate mofetil in allogeneic hematopoietic stem cell-transplanted Japanese patients

PURPOSE

Mycophenolate mofetil (MMF) is increasingly used among Japanese patients undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT). Because pharmacokinetic data for MMF in the Asian population are limited, we conducted this investigation.

METHODS

Intravenous MMF (1000 mg/dose) was administered to 10 patients along with cyclosporine or tacrolimus for 10 days after allo-SCT; it was administered every 8 h in peripheral blood stem cell- and bone marrow-transplanted patients, and every 12 h in cord blood-transplanted patients. MMF was administered orally at the same dose from day 11. Plasma concentrations of mycophenolic acid (MPA) were measured by high-performance liquid chromatography.

RESULTS

The MPA AUC_0 - tau was 31.9 ± 3.4, 26.2 ± 2.4, and 21.0 ± 2.2 µg*h/mL, the mean C_trough was 0.25, 0.35, and 0.37 µg/mL, and the C_max was 10.8, 9.2, and 5.5 µg/mL on days 2, 9, and 16, respectively. The AUC_0 - tau and C_max were significantly higher after intravenous MMF dosing than after oral MMF dosing. All patients exhibited successful neutrophil engraftments in a median time of 18 days. Grade II acute graft-versus-host disease (GvHD) of the skin was observed in two patients, and one patient developed limited chronic GvHD. Individual cases of transient and curable grade III oral mucositis and diarrhea were observed; however, MMF was not discontinued. No other severe complications or infections were observed.

CONCLUSIONS

Intravenously administered MMF was safe and possibly effective in achieving higher MPA plasma concentrations for GvHD prophylaxis after allo-SCT in Japanese patients.

Curcumin Enhanced Busulfan-Induced Apoptosis through Downregulating the Expression of Survivin in Leukemia Stem-Like KG1a Cells

Leukemia relapse and nonrecurrence mortality (NRM) due to leukemia stem cells (LSCs) represent major problems following hematopoietic stem cell transplantation (HSCT). To eliminate LSCs, the sensitivity of LSCs to chemotherapeutic agents used in conditioning regimens should be enhanced. Curcumin (CUR) has received considerable attention as a result of its anticancer activity in leukemia and solid tumors. In this study, we investigated the cytotoxic effects and underlying mechanisms in leukemia stem-like KG1a cells exposed to busulfan (BUS) and CUR, either alone or in combination. KG1a cells exhibiting BUS-resistance demonstrated by MTT and annexin V/propidium iodide (PI) assays, compared with HL-60 cells. CUR induced cell growth inhibition and apoptosis in KG1a cells. Apoptosis of KG1a cells was significantly enhanced by treatment with CUR+BUS, compared with either agent alone. CUR synergistically enhanced the cytotoxic effect of BUS. Seven apoptosis-related proteins were modulated in CUR- and CUR+BUS-treated cells analyzed by proteins array analysis. Importantly, the antiapoptosis protein survivin was significantly downregulated, especially in combination group. Suppression of survivin with specific inhibitor YM155 significantly increased the susceptibility of KG1a cells to BUS. These results demonstrated that CUR could increase the sensitivity of leukemia stem-like KG1a cells to BUS by downregulating the expression of survivin.

The Incidence and Severity of Oral Mucositis among Allogeneic Hematopoietic Stem Cell Transplantation Patients: A Systematic Review

Oral mucositis (OM) is a debilitating early adverse effect of allogeneic hematopoietic stem cell transplantation (HSCT). The intensity of the conditioning regimen correlates with the incidence and severity of OM, but no studies have analyzed this relationship among various conditioning regimens. We performed a systematic review on the incidence and outcomes of OM in allogeneic HSCT patients and analyzed this association. A comprehensive search of several databases (Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Cochrane CRCT, Cochrane DSR, Scopus) from 1990 to 2014 for studies of OM in allogeneic HSCT patients was conducted. Professional societies' meeting abstracts were also searched. Grade of OM was analyzed based on the World Health Organization (WHO) or National Cancer Institutes (NCI) Common Terminology Criteria for Adverse Events scales. Severe mucositis was defined as either grades 2 to 4 or grades 3 and 4, depending on the studies' definition of severity. Cohorts were analyzed based on regimen intensity; ie, reduced-intensity conditioning (RIC) (including nonmyeloablative) and myeloablative (MA). Random effect (RE) and standard logistic models weighted by the number of patients in each cohort were used for comparisons. A total of 624 studies were generated from the search. Of the 395 patients in 8 eligible MA regimen studies, 73.2% experienced any OM, whereas in 245 patients in the 6 eligible RIC regimen studies, 86.5% experienced any OM (chi-square P < .0001; RE, P = .05). Severe (grades 2 to 4) OM occurred among 79.7% of the WHO/NCI-graded MA patients and 71.5% of RIC patients (chi-square, P = .0421; RE, P < .01). In comparing graft-versus-host disease (GVHD) prophylaxis, only 55.4% of patients receiving nonmethotrexate regimens experienced OM; this was lower (chi-square, P < .0001; RE, P = .06) than that found among patients who received methotrexate (83.4%), either standard or reduced dose. Besides NCI and WHO grading scales, other scales included in the studies were Oral Mucositis Index, the Southwest Oncology Group Criteria, and Eastern Cooperative Oncology Group scale. To our knowledge, this is the first analysis on OM in allogeneic HSCT patients with respect to conditioning regimens, and we observed that RIC regimens led to a high incidence of OM similar to that of MA regimens. Clinical trials on treatment of OM are lacking, emphasizing the essential need for prospective studies in this arena. A significant variance in the criteria for grading OM underscores the importance of establishing a standard grading system for OM measurement in future allogeneic HSCT clinical trials.

HLA haploidentical peripheral blood stem cell transplantation using reduced dose of posttransplantation cyclophosphamide for poor-prognosis or refractory leukemia and myelodysplastic syndrome

Nonmyeloablative, human leukocyte antigen (HLA) haploidentical, T-cell-replete bone marrow transplantation followed by high-dose posttransplantation cyclophosphamide (PT/Cy) has recently been developed. This transplantation milieu has resulted in favorable outcomes with low transplantation-related mortality, owing to a low incidence of graft-versus-host disease (GVHD), without increased infectious complications. However, the high relapse rate remains a major concern. We therefore performed a prospective pilot study of HLA haploidentical peripheral blood stem cell transplantation (PBSCT) with intensified conditioning, followed by two lower doses of PT/Cy. A total of 20 patients with refractory or poor-prognosis myelodysplastic syndrome (MDS) and leukemia were enrolled in the study. A trend toward a lower incidence of grade III-IV acute GVHD at day 100 in the group receiving 25 mg/kg × 2 doses of PT/Cy, compared with the group receiving 25 mg/kg of PT/Cy (9.1% vs. 33%, p = 0.20), was noted. However, the cumulative incidence of chronic GVHD was low, at 10% irrespective of PT/Cy dose. The number of infused CD34(+) cells significantly correlated with the grade of acute GVHD (p = 0.004). In addition, the occurrence of BK virus hemorrhagic cystitis was significantly more common in the double-dose PT/Cy group (25% vs. 0%, p = 0.043), especially when combined with busulfan. The probability of overall survival at 1 year in the double-dose group tended to be better compared with that in the single-dose group (64% vs. 44%, respectively; p = 0.20). In conclusion, HLA haploidentical, T-cell-replete PBSCT with 25 mg/kg × 2 doses of PT/Cy might be a feasible option for treating high-risk leukemia and MDS.