Abstract

Allogeneic blood or marrow transplantation (alloBMT) is standard of care for adults with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) in first complete remission (CR1). The routine pretransplant and posttransplant use of tyrosine kinase inhibitors (TKIs) has dramatically improved outcomes, but the optimal conditioning regimen, donor type, and TKI remain undefined. The bone marrow transplant database at Johns Hopkins was queried for adult patients with de novo Ph+ ALL who received alloBMT using posttransplantation cyclophosphamide (PTCy) as a component of graft-versus-host disease (GVHD) prophylaxis from 2008 to 2018. Among transplants for Ph+ ALL, 69 (85%) were performed in CR1, and 12 (15%) were performed in second or greater remission (CR2+). The majority of transplants (58%) were HLA haploidentical. Nearly all patients (91.4%) initiated TKI posttransplant. For patients in CR1, the 5-year relapse-free survival (RFS) was 66%. The use of nonmyeloablative conditioning, absence of measurable residual disease (MRD) according to flow cytometry at transplant, and the use of dasatinib vs imatinib at diagnosis were associated with improved overall survival (OS) and RFS. Neither donor type nor recipient age ≥60 years affected RFS. When analyzing all transplants, alloBMT in CR1 (vs CR2+) and the absence of pretransplant MRD were associated with improved RFS. Most relapses were associated with the emergence of kinase domain mutations. The cumulative incidence of grade 3 to 4 acute GVHD at 1 year was 9%, and moderate to severe chronic GVHD at 2 years was 8%. Nonmyeloablative alloBMT with PTCy for Ph+ ALL in an MRD-negative CR1 after initial treatment with dasatinib yields favorable outcomes.

Abstract

BACKGROUND Anti-thymocyte globulin (ATG) is widely used to prevent graft-versus-host disease (GVHD) after allogeneic peripheral blood stem cell transplantation (alloPBSCT). The goal of this study was to retrospectively assess the effect of ATG on outcomes in the setting of Philadelphia chromosome-positive acute lymphoblastic leukaemia (Ph+ ALL). METHODS In the analysis, 1170 adult patients undergoing alloPBSCT from human leucocyte antigen-matched sibling or unrelated donors in the first complete remission between 2007 and 2016 were included. ATG was used in 429/575 (75%) and 121/595 (20%) patients transplanted from unrelated or sibling donors, respectively. RESULTS The incidence of chronic GVHD was 35% for patients treated with ATG compared with 52% in those not receiving ATG (p < 0.001), while the rate of extensive chronic GVHD was 16% and 36%, respectively (p < 0.001). The probability of survival free from GVHD and relapse (GRFS) was 42% and 32%, respectively (p = 0.002). In a multivariate model, the use of ATG was associated with reduced risk of overall chronic GVHD (hazard ratio [HR] = 0.52, p < 0.001) and extensive chronic GVHD (HR = 0.46, p < 0.001). It was also associated with better GRFS (HR = 0.77, p = 0.007), despite increased risk of relapse (HR = 1.41, p = 0.02). No significant effect was found with regard to the risk of non-relapse mortality and overall mortality. CONCLUSIONS The use of ATG for patients with Ph+ ALL undergoing alloPBSCT is associated with reduced risk of chronic GVHD without impact on survival and therefore, could be considered. However, increased risk of relapse suggests the need for strict monitoring of minimal residual diseases and appropriate interventions after transplantation.

Abstract

BACKGROUND Mobilized peripheral blood stem cells are currently the predominant source of grafts for allogeneic transplantation (allogeneic peripheral blood stem cell transplantation [allo-PBSCT]), although, in comparison with bone marrow, their use is associated with an increased risk of chronic graft-versus-host disease (cGVHD). Attempts to reduce the incidence of cGVHD include the addition of anti-thymocyte globulin (ATG) to the pretransplant conditioning regimen. METHODS The goal of this retrospective study was to analyze the effect of ATG on allo-PBSCT outcomes for adults with Philadelphia-negative acute lymphoblastic leukemia (Ph-neg ALL). The primary endpoint was survival free from relapse, grade 3 to 4 acute graft-versus-host disease (aGVHD), and cGVHD (ie, graft-versus-host disease-free/relapse-free survival [GRFS]). Nine-hundred twenty-four patients who underwent unmanipulated allo-PBSCT in their first complete remission between 2007 and 2016 were included. ATG was used in 97 of the 494 transplants from matched sibling donors (20%) and in 307 of the 430 transplants from human leukocyte antigen-matched (8 of 8 loci) unrelated donors (71%). RESULTS The use of ATG was an independent factor for an improved chance of GRFS (hazard ratio [HR], 0.70; P = .0009). Furthermore, it was associated with a reduced risk of both grade 2 to 4 (HR, 0.66; P = .005) and grade 3 to 4 aGVHD (HR, 0.58; P = .03). Similarly, its addition reduced the incidence of both total (HR, 0.45; P < 10(-5) ) and extensive cGVHD (HR, 0.30; P < 10(-5) ) as well as nonrelapse mortality (HR, 0.58; P = .01). No significant effect was found with respect to leukemia-free or overall survival. However, an increased risk of relapse was noted for those who received ATG (HR, 1.40; P = .04). CONCLUSIONS Patients with Ph-neg ALL treated with allo-PBSCT benefit from the use of ATG in terms of improved GRFS. Its use may, therefore, be considered in this setting. Cancer 2018. (c) 2018 American Cancer Society.

Abstract

Haploidentical transplantation performed with post-transplantation cyclophosphamide (PTCy)-based graft-versus-host disease (GVHD) prophylaxis has been associated with favorable outcomes for patients with acute myeloid leukemia and lymphomas. However, it remains unclear if such approach is effective for patients with acute lymphoblastic leukemia (ALL). We analyzed outcomes of 109 consecutively treated ALL patients 18 years of age and older at 5 institutions. The median age was 32 years and the median follow-up for survivors was 13 months. Thirty-two patients were in first complete remission (CR1), while the rest were beyond CR1. Neutrophil engraftment occurred in 95% of the patients. The cumulative incidences of grades II to IV and III and IV acute GVHD at day 100 after transplantation were 32% and 11%, respectively, whereas chronic GVHD, nonrelapse mortality, relapse rate, and disease-free survival (DFS) at 1 year after transplantation were 32%, 21%, 27%, and 51%, respectively. Patients in CR1 had 52% DFS at 3 years. These results suggest that haploidentical transplants performed with PTCy-based GVHD prophylaxis provide a very suitable alternative to HLA-matched transplantations for patients with ALL.

Abstract

Clinical efficacy of post-transplantation cyclophosphamide (PTCy) as graft-versus-host disease (GVHD) prophylaxis has been demonstrated in haploidentical and HLA-matched bone marrow but not in unrelated peripheral blood stem cell (PBSC) transplantations. Also, no direct comparisons have been published with current standard of care, combination of antithymocyte globulin (ATG), calcineurin inhibitors, and either methotrexate or mycophenolate mofetil (MMF). Eighty-six adult patients (median age 34 years; range, 18 to 59) with acute myeloblastic and lymphoblastic leukemia underwent unrelated PBSC transplantation with PTCy, tacrolimus, and MMF as GVHD prophylaxis in the single-center trial (clinicaltrial.govNCT02294552). The control group comprised 125 consecutive historical control patients who received ATG, tacrolimus, and methotrexate or MMF. Cumulative incidences of grades II to IV acute (19% versus 45%, P = .0003), grades III to IV acute (4% versus 27%, P < .0001), and chronic GVHD (16% versus 65%, P < .0001) were significantly lower in the PTCy compared with the ATG group. PTCy-based prophylaxis was associated with reduced incidence of nonrelapse mortality (16% versus 36%, P = .005; HR, .55; 95% CI, .34 to .89) and improved overall survival (69% versus 40%, P = .0007; HR, .43; 95% CI, .26 to .70), event-free survival (65% versus 38%, P = .0006; HR, .49; 95% CI, .31 to .78), and GVHD relapse-free survival (52% versus 12%, P < .0001). PTCy-based prophylaxis also had a better safety profile compared with ATG with reduced incidence of veno-occlusive disease, cytomegalovirus reactivation, invasive mycosis, and reduced severity of mucositis. In this study we demonstrated that PTCy in combination with tacrolimus and MMF is a safe and effective GVHD prophylaxis for unrelated PBSC transplantation. Although there are several limitations of the historical control approach, this study suggests the superiority of a PTCy-based approach over an ATG-based prophylaxis. Copyright © 2016 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Abstract

There is currently a major concern regarding the optimal immunosuppression therapy to be administered after hematopoietic stem cell transplantation (HSCT) to reduce both the toxicity of GvHD and the rate of relapse. We report the outcome of high-risk leukemia children transplanted with a new way of managing cyclosporine (CsA)-based GvHD prophylaxis. A total of 110 HSCT in 109 ALL or AML children who received CsA without mycophenolate or methotrexate in matched related as well as in matched or mismatched unrelated stem cell transplantation were included. CsA dosage regimens were individualized to obtain specific trough blood concentrations values. The incidences of grade I-II and III-IV acute GvHD were 69.1% and 1.8%, respectively, and 8.4% for chronic GvHD. GvHD was neither more frequent nor severe in unrelated than in related HSCT. GvHD occurred in 87% of patients with a mean CsA trough concentration 120ng/mL versus 43% with concentration >120ng/mL (P<0.0001). Five-year disease-free survival (DFS) and overall survival were 78% and 83.6%, respectively. DFS was 76.9% for ALL and 80.4% for AML patients. There was no difference in DFS between matched siblings and matched unrelated or mismatched unrelated HSCT. DFS in patients with minimal residual disease (MRD) 10(-3) and in those with MRD <10(-3) before SCT was comparable. Our results indicate that a GvHD prophylaxis regimen based on CsA without mycophenolate or methotrexate is safe and effective whatever the donor compatibility is. These results suggest that GvL effect may be enhanced by this strategy of GvHD prophylaxis.