Clinical and economic comparison of allogeneic peripheral blood progenitor cell and bone marrow transplantation for acute lymphoblastic leukemia in children

There is limited experience in the use of peripheral blood progenitor cells (PBPC) for allogeneic transplantation in children. In the present study we compared engraftment kinetics, incidence of acute and chronic graft-versus-host disease (GVHD) and the outcome and economic costs of allogeneic PBPCT vs BMT in children with ALL in a single institution. All children were transplanted in complete remission (CR) with a similar conditioning regimen and the same GVHD prophylaxis. Patients undergoing PBPCT achieved myeloid and platelet engraftment before patients undergoing BMT (P < 0.001). Platelet recovery was faster for the PBPCT group (P < 0.014 for 50 x 10(9)/l and P < 0.039 for 100 x 10(9)/l). Incidence and severity of acute and chronic GVHD were similar in both groups (acute grade 1-2: 9/13 for PBPCT vs 9/11 for BMT; chronic GVHD: 5/12 for PBPCT vs 3/8 for BMT). Hospital stay was shorter for the PBPCT than for the BMT group (28.8 days vs 42.9 days, respectively) and the PBPCT group used less clinical resources, resulting in overall lower cost for PBPCT (US $14,046) compared to BMT (US $19,840). There was no statistically significant difference in DFS between PBPCT and BMT (68.4% vs 50%, respectively).     

A randomised study of allogeneic transplantation with stem cells from blood or bone marrow

Sixty-one consecutive adult patients with leukaemia, primary myelofibrosis or myelodysplastic syndrome with an HLA-identical or one antigen mismatched family donor were randomised to allogeneic transplantation with PBPC or BM. Progenitor cells were mobilised into the blood by giving the donors 10 microg/kg/day G-CSF subcutaneously for 5-7 days. G-CSF was not given to patients after transplantation. The time to neutrophil counts >0.5 x 109/l was 17 days (95% CI 15.2-18.8 days) in the PBPC group compared to 23 (95% CI 20.3-25.7 days) in the BM group (P = 0.0005). The time to platelet counts >20 x 109/l was 13 days (95% CI 11.7-14.3 days) in the PBPC group and 21 days (95% CI 18.7-23.3 days) in the BM group (P = 0.0005). Acute GVHD of grades II-IV developed in six patients transplanted with PBPC and three patients transplanted with BM. The numbers of patients with chronic GVHD were 15 and 8, respectively. Transplant-related mortality and leukaemia-free survival showed no significant differences. Transplantation with PBPC appears preferable for the recipient due to faster neutrophil and platelet recovery. However, the final conclusion can not be drawn before long-term results on chronic GVHD and relapse incidence in longer randomised trials are available.     

A randomized multicenter comparison of CD34(+)-selected progenitor cells from blood vs from bone marrow in recipients of HLA-identical allogeneic transplants for hematological malignancies

OBJECTIVE: Peripheral blood progenitor cells (PBPC) have been established as an alternative source of hematopoietic stem cells for allogeneic transplantation, but an increased incidence of both acute and chronic graft-vs-host disease (GVHD) has become apparent. We performed a prospective randomized trial comparing bone marrow transplantation (BMT) vs PBPC transplantation (PBPCT) using CD34(+) selection for T-cell depletion (TCD) in both study arms. PATIENTS AND METHODS: Between January 1996 and October 2000, 120 patients with a diagnosis of acute leukemia, myelodysplasia, multiple myeloma, or lymphoma were randomized to receive either filgrastim-mobilized PBPC or BM from HLA-identical sibling donors after standard high-dose chemoradiotherapy. Patient characteristics did not differ between study arms. RESULTS: Recipients of PBPC received more CD3(+) T cells (median: 3.0 vs 2.0 x 10(5)/kg, p<0.0001) and more CD34(+) cells (median: 3.6 vs 0.9 x 10(6)/kg, p<0.0001). Neutrophil and platelet recoveries occurred significantly faster after PBPCT. The cumulative incidence of acute GVHD grades II-IV was 37% after BMT vs 52% after PBPCT and was most significantly (p=0.007) affected by the number of CD3(+) T cells in the graft. Acute GVHD appeared strongly associated with increased treatment-related mortality (TRM) in a time-dependent analysis. Higher numbers of CD34(+) cells were associated with less TRM. With a median follow-up of 37 months (range: 12-75), overall survival at 4 years from transplantation was 60% after BMT and 34% for recipients of PBPCT (p=0.04), which difference was largely due to increased GVHD and TRM in PBPC recipients receiving T-cell dosages greater than 2 x 10(5)/kg. CONCLUSION: Outcome following T cell-depleted PBPCT critically depends on the number of CD3(+) T cells, whereby high T-cell numbers may blunt a favorable effect of higher CD34(+) cell numbers.     

Favourable outcome of patients older than 40 years of age after transplantation with marrow grafts depleted of lymphocytes by counterflow centrifugation

Nineteen patients with a median age of 43 years (range 40-48) were transplanted for acute myelogenous leukaemia (AML), refractory anaemia with excess of blasts in transformation (RAEBt), acute lymphoblastic leukaemia (ALL) in first complete remission, multiple myeloma, and chronic myelogenous leukaemia (CML) in chronic or accelerated phase. Their outcome was compared with that of 35 patients with a median age of 34 years (range 30-39), and a group of patients with age younger than 30 years (median 24; range 16-29) transplanted for the same indications. Donors were human leucocyte antigen (HLA)-identical, mixed lymphocyte culture (MLC) negative siblings. All marrow grafts were depleted of lymphocytes by counterflow centrifugation. The estimated event-free survival at 3 years after allogeneic bone marrow transplantation was 60.7% for patients with age greater than 39 years, 57.8% for patients with age less than 30, and 43.0% for the intermediate age group (P greater than 0.3). The estimated transplant-related mortality showed no tendency to increase with older age of recipients. The incidence of acute GVHD greater than grade 1 was 15.7% in patients with age greater than 39 years, 9.5% in patients younger than 30 years, and 23% in the intermediate age group. The incidence of chronic GVHD was higher in the older patients (39% compared to 24% in patients younger than 30 years, 19% in the intermediate age group). Chronic GVHD resolved completely in five out of seven patients aged 40 years or more. Reduction of the incidence of acute graft-versus-host disease by physical lymphocyte depletion allows allogeneic bone marrow transplantation for patients aged 40-50 years without increase of transplant-related mortality resulting in similar event-free survival in patients older than 40 years compared to those younger than 40 years.     

A comparison of postengraftment infectious morbidity and mortality after allogeneic partially T cell-depleted peripheral blood progenitor cell transplantation versus T cell-depleted bone marrow transplantation

OBJECTIVE: Postengraftment infections are a major cause of transplant-related morbidity and mortality following allogeneic hematopoietic stem cell transplantation (allo-SCT). Allogeneic peripheral blood progenitor cell transplantation (PBPCT) is associated with faster hematopoietic recovery compared to bone marrow transplantation (BMT) and unmanipulated PBPCT may be associated with fewer postengraftment infections. We set out to evaluate and compare the incidence, cause, and outcome of postengraftment infections following HLA-identical sibling T cell-depleted PBPCT vs T cell-depleted BMT between days 30 and 365 posttransplant. PATIENTS: Forty recipients of peripheral blood progenitor cells (PBPC) and 47 recipients of bone marrow (BM) were included. The two groups of patients were comparable with respect to their baseline characteristics. RESULTS: PBPC grafts contained significantly more CD34+ cells and PBPCT was associated with significantly faster neutrophil and lymphocyte recovery as compared to BMT. PBPC recipients experienced more chronic graft-vs-host disease (GVHD; 55% vs 34%; p=0.02). The number of definite and clinical infections per 100 patient days was comparable between recipients of PBPC and BM with similar contribution of causative microorganisms. At one year post SCT, 68% of PBPC recipients had experienced at least one CTC grade 3-4 infection vs 65% of BM recipients. Treatment-related mortality at one year from transplantation was 34% after PBPCT vs 30% after BMT, and no difference in infection-related mortality was observed. CONCLUSION: Postengraftment infectious morbidity and mortality were comparable between recipients of PBPC and BM despite a higher CD34+ cell content of PBPC grafts and faster lymphocyte recovery after PBPCT, which may in part be explained by the higher incidence of chronic GVHD.     

Early lymphocyte recovery post-allogeneic hematopoietic stem cell transplantation is associated with significant graft-versus-leukemia effect without increase in graft-versus-host disease in pediatric acute lymphoblastic leukemia

To study the effect of early lymphocyte recovery post-allogeneic hematopoietic stem cell transplantation (HSCT) on outcome in pediatric ALL, we reviewed 136 consecutive pediatric patients with ALL who received allogeneic HSCT between 1994 and 2005 at the Hospital for Sick Children, Toronto, Canada. Patients with an absolute lymphocyte count (ALC) <0.3 x 10(9) per liter at day 21 (n=104) had more than five times risk of relapse compared to those with ALC >0.3 x 10(9) per liter (n=32) (hazard ratio (HR) 5.3; P=0.002) and had inferior 3-year event-free survival, (EFS), 0.42 (95% confidence interval (CI) 0.32, 0.51) compared to 0.66 (95% CI 0.48, 0.82; P=0.02). Similarly, patients with an ALC <0.3 x 10(9) per liter (n=48) at day 30 were more than twice as likely to relapse compared to those with an ALC >0.3 x 10(9) per liter (n=88) (HR 2.2; P=0.01) and had an inferior 3-year EFS, 0.30 (95% CI 0.18, 0.45) compared to 0.57 (95% CI 0.46, 0.68; P=0.0001). Interestingly, increasing ALC at days 21 and 30 was not associated with increased incidence of acute or chronic GVHD or transplant-related mortality (TRM). Early lymphocyte recovery post-HSCT is associated with a significant GVL without increase in GVHD.     

HLA-identical sibling peripheral blood progenitor cell transplants (PBPCT).

Peripheral blood progenitor cells (PBPC) are being investigated as an alternative stem cell source in allogeneic transplantation. The current paper presents a 'state-of-the-art' review of HLA-identical sibling transplants (PBPCT). Medline search and meeting reports were used to identify the latest reports from the various transplant centers. The data are presented systematically with the goal of providing a basis for evidence-based medicine. This approach offered the opportunity to identify threshold CD34+ cell numbers for rapid engraftment, threshold CD3+ cell numbers to prevent acute GVHD, prognostic factors for various outcome parameters and are a strong indication that the infused CD3+ cell dose might influence chronic graft-versus-host disease (GVHD), the most controversial and concerning aspect in allogeneic PBPCT. The value of systematic reviews for future clinical research planning is emphasized.     

Treatment of myelodysplastic syndrome with busulfan-cyclophosphamide conditioning followed by allogeneic BMT.

Twenty-three consecutive patients undergoing related-donor BMT for myelodysplastic syndrome (MDS) were conditioned with a combination of busulfan (BU) and cyclophosphamide (CY). GVHD prophylaxis was with cyclosporine (CSP)/methotrexate (MTX) in 15 patients, CSP/methylprednisolone (MP) in six patients, and CSP/MP/MTX in two patients. The most frequent regimen-related toxicities were oral mucosal (87% of patients, 61% > or = grade II) and hepatic (82% of patients, 43% > or = grade II). The overall incidence of grade II-IV acute GVHD was 48% with eight patients dying of acute or chronic GVHD. There have been five relapses, with the cumulative risk of relapse being 35% (95% confidence interval [CI], 16%-66%). Eight patients remain alive and well (median follow-up 27 months, range 15-70 months), with an estimated 3-year event-free survival (EFS) of 35% (95% CI, 17%-54%). Univariate analysis of EFS by pretransplant variables indicated that only age < or = 35 years correlated with a favorable outcome (p = 0.04). BUCY is an effective, well-tolerated alternative conditioning regimen for MDS patients undergoing allogeneic BMT.     

Factors affecting long-term outcome after allogeneic haematopoietic stem cell transplantation for acute myelogenous leukaemia: a retrospective study of 172 adult patients reported to the Austrian Stem Cell Transplantation Registry

Between 1982 and 2000, 172 patients with acute myelogenous leukaemia (AML) received haematopoietic stem cell transplants (SCT) from related (n = 132) or unrelated (n = 40) donors at four Austrian transplant centres and their results were reported to the Austrian Stem Cell Transplantation Registry. Conditioning for SCT consisted of cyclophosphamide and total body irradiation in 156 (91%) patients. Graft-versus-host disease (GVHD) prophylaxis was with standard cyclosporine and methotrexate in 95 (55%) patients. Median post-transplant follow-up was 5.6 years (range, 0.2--16.7). Multivariate analysis of transplant-related mortality (TRM) identified four variables associated with a lower risk: disease status of first complete remission (CR) at SCT, patient age of 45 years and younger, transplant performed during or after 1995, and lack of acute GVHD. Variables associated with significantly improved leukaemia-free survival were: bone marrow as the stem cell source, disease status of first CR at SCT, and occurrence of chronic GVHD. In multivariate analysis, transplantation performed during or after 1995, first CR at SCT, occurrence of limited chronic GVHD and lack of acute GVHD grades III to IV were associated with increased overall survival. Based on these analyses, options for the improvement of results obtained with allogeneic SCT in patients with AML could be defined.     

The addition of allogeneic peripheral blood-derived progenitor cells to bone marrow for transplantation: results of a randomised clinical trial

Background: The use of cytokine-mobilised peripheral-blood-derived progenitor cells (PBPC) has resulted in a significant improvement in the safety of autologous transplantation. Collections of PBPC contain large numbers of haemopoietic progenitors and T-lymphocytes when compared with bone marrow (BM). Aims: To assess the clinical effects and safety of filgrastim-mobilised allogeneic PBPC, in particular whether PBPC would alter the kinetics of engraftment or the incidence and severity of graft-versus-host disease (GVHD). Methods: Twenty-seven patients undergoing allogeneic transplantation were randomised to receive BM or BM supplemented by PBPC. Patients were conditioned with busulphan 16 mg/kg and cyclophosphamide 120 mg/kg. GVHD prophylaxis was with methotrexate and cyclosporin. Ganciclovir prophylaxis was administered to all cytomegalovirus seropositive patients. No haemopoietic growth factor was used after BMT. Donors of PBPC underwent a single, seven litre apheresis after four days of filgrastim, 10 μg/kg/day by subcutaneous injection. Results: Donor toxicity was mild, with the most frequently reported being bone pain in the cytokine-treated donors. The patients transplanted with BM+PBPC received an eight-fold increase in CD3+ T-lymphocytes (1.65X10⁸kg vs 0.22×10⁸/kg, p=0.04) and the cytokine product contained a median of 5×10⁶ CD34+ cells/kg. BM+PBPC patients had more rapid engraftment of neutrophils to 0.5×10⁹/L (17 days vs 19 days, p=0.02) and platelets to 50×10⁹/L (22 days vs 35 days, p=0.04). BM megakaryocyte numbers were significantly enhanced at days 14 and 28 after BMT (both p=0.04), however platelet transfusions were not significantly different. The incidence, organ distribution, severity and time to onset of acute and chronic GVHD were not different between the treatment groups and there was no difference in overall survival or event-free survival. Conclusions: Allogeneic PBPC from HLA-identical siblings may speed engraftment of neutrophils and platelets without detrimental effects on GVHD or survival.     

Allogeneic bone marrow transplantation for chronic myeloid leukemia in childhood: a report from the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC)

To determine the results of allogeneic hematopoietic stem cell (HSC) transplantation for chronic myelogenous leukemia (CML) at various stages of the disease in children, a retrospective analysis was carried out on the outcome of transplants performed on 76 children and teenagers with CML between 1982 and 1998. In all, 60 patients were transplanted from a matched sibling donor (MSD) and 16 from a matched unrelated donor (MUD). There was a higher incidence of acute graft-versus-host disease after MUD transplantation (P<10(-3)). The main cause of death was transplant-related toxicity in both groups. In MSD recipients, the probability of relapse at 5 years for patients transplanted in the first chronic phase was lower than in patients transplanted in the advanced phase (relative risk (rr)=5.90; 95% confidence interval (CI), 1.85-18.82, P<0.01). The estimated 5-year event-free survival (EFS) rate was higher after MSD vs MUD transplantation (61% (95% CI, 48-73%) vs 27% (95% CI, 4-49%), rr=0.25, P<10(-3)). In children transplanted from MSD, the 5-year EFS was higher when transplantation was performed in the first chronic phase vs the advanced phases (73% (95% CI, 59-87%) vs 32% (95% CI, 10-54%), P<10(-3)). Disease status at transplantation was the unique factor influencing survival in patients undergoing transplantation from MSD with a better outcome for those transplanted in the first chronic phase. Allogeneic HSC offers a possibility of curing childhood CML with a significant advantage for patients transplanted in chronic phase using a human leukocyte antigen-identical sibling donor.     

Myeloablative allogeneic stem cell transplantation for advanced stage multiple myeloma: very long-term follow up of a single center experience

We aimed to review the long-term outcome of myeloablative allogeneic stem cell transplantation (SCT) performed for multiple myeloma (MM) at our institution. Records of all patients who received standard myeloablative allogeneic SCT for MM were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), and event-free survival (EFS) were calculated using the Kaplan-Meier method. In total 37 transplants had been performed. Median follow up post-SCT was 108 months (range: 33-148). The majority of patients suffered advanced stage disease and/or had received multiple prior therapies prior to SCT. Transplant-related mortality (TRM) at 100 days was 32%. Grades 2-4 acute graft-vs.-host disease (GVHD) occurred in 18 patients (49%), and extensive stage chronic GVHD in seven (28%) of 25 patients surviving greater than day 100. Median OS, PFS, and EFS were 28 months, 66 months and 13 months, respectively, with 5 year OS, PFS, and EFS 40%, 54% and 24%. Our results suggest that allogeneic SCT, even when performed in advanced stage, heavily pretreated MM, still results in long-term EFS in a significant minority of patients. Efforts should continue on alternative allogeneic SCT approaches to reduce the high early TRM rate associated with myeloablative conditioning.     

Donor T-lymphocyte infusion for unrelated allogeneic bone marrow transplantation with CD3+ T-cell-depleted graft

In T-cell-depleted allogeneic bone marrow transplantation (TCD-BMT) using unrelated donors, the role of donor lymphocyte infusion (DLI) for survival and disease control has not been defined. In a study of 116 patients (92 matched, 24 mismatched) who received CD3+ T-cell-depleted marrow graft, sequential infusions of escalated doses of donor T lymphocytes up to 1 x 10(6) CD3+ cells/kg were prospectively investigated. T cells were administered while patients were on cyclosporine, provided >or=grade II acute graft-versus-host-disease (GVHD) had not occurred. Acute GVHD of >or=grade II occurred in 27 of 110 (25%) patients before DLI and in 39 of 79 (49%) patients after DLI. In total, 12 of 27 (44%) patients without DLI and 44 of 72 (61%) patients who received DLI developed chronic GVHD. A total of 19 patients died of GVHD, with 17 of acute and two of chronic GVHD. Overall survival (OS) and event-free survival (EFS) at 5 years were 27 and 21%, respectively. The 2-year incidence of relapse was 14%. In multivariate analysis, only chronic GVHD was a good prognostic factor for both OS: hazard ratio (HR) 1.4, P=0.04, and EFS: HR 1.6, P=0.01. Both acute and chronic GVHD were favorable prognostic factors for relapse probability: HR 1.9 for both, P=0.02, 0.01, respectively. The 1-year cumulative incidence of transplant-related mortality (TRM), excluding cases of GVHD, was 42%. The two most common causes of 1-year non-GVHD death were viral infection (9%) and idiopathic pneumonia syndrome (12%). Although the incidence of relapse was low, the study suggests that the current scheme of DLI in unrelated TCD-BMT would not improve survival unless TRM decreases significantly.     

Long-term results of bone marrow transplantation for patients with AML, ALL and CML prepared with single dose total body irradiation of 500 cGy delivered with a high dose rate.

One hundred and sixty-six patients between the ages of 12 and 48 years with acute myelogenous leukemia (AML), acute lymphoblastic leukemia (ALL) or chronic myelogenous leukemia (CML) underwent allogeneic bone marrow transplantation following single fraction total body irradiation (TBI) of 500 cGy from a cobalt source. Patients also received one of three chemotherapeutic regimens according to their diagnosis or disease status at time of transplant. The median follow-up was 67 months with a range of 33-120 months. The actuarial 5-year event-free survival (EFS) for the subgroup of patients with good risk disease (first complete remission AML and ALL or first chronic phase CML) was 43% with an actuarial relapse rate at 5 years of 26%. Patients with poor risk disease (other than first remission AML and ALL or other than first chronic phase CML) had an EFS at 5 years of 15% with a relapse rate of 62%. Disease status at the time of transplantation was the most important factor predicting outcome in this patient population. We conclude that preparation of good risk patients with chemotherapy and single fraction TBI of 500 cGy at a dose rate of 42-91 cGy/min resulted in EFS and relapse rates similar to those observed by centers using fractionated radiotherapy schedules, without a concomitant increase in toxicity, in particular interstitial pneumonitis and cataracts.     

The Japanese cord blood bank network experience with cord blood transplantation from unrelated donors for haematological malignancies: an evaluation of graft-versus-host disease prophylaxis

Cryopreserved umbilical cord blood (CB) from unrelated donors can restore haematopoiesis after myeloablative therapy in patients with haematological malignancy. We investigated the clinical outcomes of CB transplantation (CBT) with special emphasis on graft-versus-host disease (GVHD) prophylaxis. Patients with haematological malignancies (n = 216) received intensive chemotherapy or immunosuppressive therapy, followed by transplantation of cryopreserved CB cells from unrelated donors. The clinical outcomes, i.e. haematological reconstitution, the incidence of acute or chronic GVHD, relapse and event-free survival (EFS), were evaluated. The estimated probability of neutrophil recovery was 88.2%. The median follow-up for the survivors was 557 d (range 21-1492 d). The overall and EFS rates were 32.6% and 25.5%, respectively, 3.5 years after transplantation. Multivariate analysis using Cox's proportional hazards model showed that high-risk disease status at CBT and single-drug GVHD prophylaxis were associated with worse 2-year EFS rates [P = 0.0013, relative risk (RR) 1.90, 95% confidence interval (CI) 1.28-2.81 and P = 0.0007, RR 1.91, 95% CI 1.31-2.79 respectively). Age at CBT had no significant influence on EFS. Cryopreserved CB from unrelated donors can restore haematopoiesis in patients with haematological malignancy. Although the incidence is low, the prophylaxis for acute GVHD is an important factor for survival of CBT from unrelated donors. A high rate of suitable donors was found, with a probability of 1 to every 18 CB units, when compared with human leucocyte antigen matching at other haematopoietic stem cell banks.     

Reduced-intensity allogeneic haemopoietic stem cell transplantation induces durable responses in patients with chronic B-lymphoproliferative disorders

Thirty-six patients with chronic B-lymphoproliferative disorders (B-LPD) underwent reduced-intensity allogeneic transplantation (RIT) from HLA-identical related donors. Diagnoses included follicular (n=17), mantle cell (n=9) and small lymphocytic lymphoma (n=2), and chronic lymphocytic leukaemia (n=8). Median age at transplant was 51 years (range, 30-66) and time from diagnosis was 3.4 years (range, 0.3-9.5). At transplant, 28% were in CR, 36% were in PR and 36% were chemorefractory. Conditioning therapy included fludarabine and either cyclophosphamide (n=27) or melphalan (n=9). Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin (CsA)/methotrexate (n=21), CsA/mycophenolate mofetil (n=13) or CsA alone (n=2). Eight patients died owing to acute GVHD (n=3), infection in association with chronic GVHD (n=4) and intra-abdominal bleeding (n=1). Treatment-related mortality was 8% at day 100, and 17 and 20% at one and two years, respectively. The cumulative incidence of grade II-IV acute GVHD was 58%, whereas limited and extensive chronic GVHD occurred in 25 and 56%, respectively. No patient has relapsed or progressed. At a median follow-up of 48 months, overall survival probability is 80% (95% CI, 67-93%). We confirm that RIT in chronic B-LPD can result in high and durable CR rates but with significant incidences of acute and chronic GVHD.     

Bone marrow transplantation for adolescents and young adults with sickle cell disease: Results of a prospective multicenter pilot study

We conducted a multicenter pilot investigation of the safety and feasibility of bone marrow transplantation (BMT) in adults with severe sickle cell disease (SCD) (NCT 01565616) using a reduced toxicity preparative regimen of busulfan (13.2 mg/kg), fludarabine (175 mg/m²) and thymoglobulin (6 mg/kg) and cyclosporine or tacrolimus and methotrexate for graft-vs-host disease (GVHD) prophylaxis. Twenty-two patients (median age 22 years; range 17-36) were enrolled at eight centers. Seventeen patients received marrow from an HLA-identical sibling donor and five patients received marrow from an 8/8 HLA-allele matched unrelated donor. Before BMT, patients had stroke, acute chest syndrome, recurrent pain events, were receiving regular red blood cell transfusions, or had an elevated tricuspid regurgitant jet (TRJ) velocity, which fulfilled eligibility criteria. Four patients developed grades II-III acute GVHD (18%) and six developed chronic GVHD (27%) that was moderate in two and severe in one patient. One patient died of intracranial hemorrhage and one of GVHD. Nineteen patients had stable donor chimerism, 1-year post-transplant. One patient who developed secondary graft failure survives disease-free after a second BMT. The one-year overall survival and event-free survival (EFS) are 91% (95% CI 68%-98%) and 86% (95% CI, 63%-95%), respectively, and 3-year EFS is 82%. Statistically significant improvements in the pain interference and physical function domains of health-related quality of life were observed. The study satisfied the primary endpoint of 1-year EFS ≥70%. This regimen is being studied in a prospective clinical trial comparing HLA-matched donor BMT with standard of care in adults with severe SCD (NCT02766465).     

Chimeric antigen receptor T-cell therapy as a bridge to haematopoietic stem cell transplantation for refractory/relapsed B-cell acute lymphoblastic leukemia

Although chimeric antigen receptor T cells (CAR-T) targeted at CD19 or CD22 have achieved high complete remission (CR) in refractory/relapsed B-cell acute lymphoblastic leukaemia (B-ALL), it is uncertain if allogeneic haematopoietic stem cell transplantation (allo-HSCT) should be performed after CAR-T therapy to accomplish a sustainable remission. Fifty-two cases with relapsed/refractory B-ALL who underwent allo-HSCT after CR by CD19 or CD22 CAR-T were enrolled. The median time from CAR-T infusion to allo-HSCT was 50 (34–98) days. Myeloablative reduced-intensity conditioning (RIC) with total body irradiation/fludarabine-based or busulfan/fludarabine-based regimens was used. Incidences of grade II–IV acute graft-versus-host disease (aGVHD) and severe aGVHD were 23·1% and 5·8% respectively. Of 48 evaluable cases, 16 developed chronic GVHD (cGVHD) and in three of them the pattern was extensive. With a median follow-up of 334 (41–479) days, one-year overall survival and event-free survival (EFS) were 87·7% and 73·0%. One-year relapse rate and transplant-related mortality (TRM) were 24·7% and 2·2% respectively. With quick bridge to allo-HSCT after CAR-T therapy, high EFS for refractory/relapsed B-ALL has been achieved in this relatively large cohort. Our myeloablative RIC regimens have resulted in low incidences of aGVHD, cGVHD, viral reactivation and very low TRM even majority of transplants from haploidentical donors. Long-term follow-up is warranted.     

Total body irradiation–high-dose cytosine arabinoside and melphalan followed by allogeneic bone marrow transplantation from HLA-identical siblings in the treatment of children with acute lymphoblastic leukaemia after relapse while receiving chemotherapy: a Société Française de Greffe de Moelle study

We investigated the use of a new conditioning regimen followed by allogeneic bone marrow transplantation (BMT) for treating children with acute lymphoblastic leukaemia (ALL) after relapse within 6 months of the completion of therapy. One hundred and sixteen children with acute lymphoblastic leukaemia in second or subsequent complete remission (CR) underwent allogeneic bone marrow transplantation from HLA-identical siblings after a preparative regimen comprising total body irradiation (TBI), high-dose cytosine arabinoside and melphalan (TAM regimen). The Kaplan-Meier product-limit estimate (mean ± SE) of disease-free survival (DFS) at 7 years was 59.5 ± 9% (95% confidence interval). The estimated chance of relapse was 22.5 ± 15% with a median follow-up of 88.5 months (range 51–132). 26 patients (22.4%) died with no evidence of recurrent leukaemia, mainly from interstitial pneumonitis, veno-occlusive disease or acute graft-versus-host disease (GVHD). Three factors significantly affected DFS: acute GVHD, site of relapse and, for children in second remission after a marrow relapse, the disease status at the time of transplantation. The DFS were 59.02 ± 12.6%, 37.5 ± 19.8% and 77.4 ± 15% among patients in CR2 after a marrow relapse, in CR3 or in untreated partial marrow relapse, and in CR2 after an isolated CNS relapse, respectively. The lowest DFS was seen in children with acute GVHD grades 3–4. Two significant factors were associated with relapse: the marrow status at the time of transplantation and chronic GVHD. The relapse rate was lower among children in CR2 or with chronic GVHD. We conclude that transplantation after the TAM regimen is an effective therapy for this population with acceptable toxicity, particularly for children in second remission after a very early marrow relapse, or those with early isolated CNS involvement.     

Comparison of outcome following allogeneic bone marrow transplantation with cyclophosphamide-total body irradiation versus busulphan-cyclophosphamide conditioning regimens for acute myelogenous leukaemia in first remission

We evaluated transplant-related mortality (TRM), leukaemia relapse, leukaemia-free survival (LFS) and overall survival (OS) in patients receiving busulphan and cyclophosphamide (BuCy) or cyclophosphamide and total body irradiation (CyTBI) prior to allogeneic bone marrow transplantation (BMT) for acute myelogenous leukaemia (AML) in first remission. Outcomes of 381 human leucocyte antigen (HLA)-matched sibling transplants using BuCy were compared with 200 transplants using CyTBI performed between 1988 and 1996. The incidence of hepatic veno-occlusive disease was higher with BuCy (13%) than with CyTBI (6%) (P = 0.009). Risks of acute and chronic GVHD were similar. In multivariate analysis, relapse risk was higher in the BuCy group [relative risk (RR) = 1.72; 95% confidence interval (CI), 1.05-2.81; P = 0.031]. Eleven of 373 evaluable patients in the BuCy group had a central nervous system relapse in contrast to none of 194 evaluable patients in the CyTBI group (P = 0.016). There were no differences in TRM, LFS and OS. CyTBI conditioning may lower relapse risk but produces comparable TRM, LFS and OS to BuCy for HLA-matched sibling transplantation in first remission AML.