Explore the vast range of titles available.

The association between graft-versus-host disease (GVHD) occurrence and acute myeloid leukemia (AML) relapse in patients treated with HLA-haploidentical allogeneic hematopoietic stem cell transplantation (Haplo-HCT) with post-transplant cyclophosphamide (PTCy)-based GVHD prophylaxis has remained debated. Here, we addressed this issue in patients with active AML at transplantation. 2-year cumulative incidences of relapse and leukemia-free survival (LFS) were 49% and 32.3%, respectively. There were no associations between acute nor chronic GVHD of any grade and lower relapse incidence. However, grade I acute GVHD was associated with better LFS (HR = 0.71, 95% CI 0.51–0.99, P  = 0.04). In contrast, grade III–IV acute (HR = 3.09, 95% CI 1.87–5.12, P  < 0.0001) as well as extensive chronic (HR = 3.3, 95% CI 1.81–6.04, P  = 0.0001) GVHD correlated with higher nonrelapse mortality leading to lower LFS (HR = 1.36, 95% CI 0.99–1.86, P  = 0.056 and HR = 1.97, 95% CI 1.35–2.89, P  = 0.0004, respectively). In conclusion, these data suggest a dissociation of graft-versus-leukemia effects from GVHD in patients with active AML treated with PTCy-based Haplo-HCT.

Haploidentical donors are now increasingly considered for transplantation in the absence of HLA-matched donors or when an urgent transplant is needed. Donor-specific anti-HLA antibodies (DSA) have been recently recognized as an important barrier against successful engraftment of donor cells, which can affect transplant survival. DSA appear more prevalent in this type of transplant due to higher likelihood of alloimmunization of multiparous females against offspring’s HLA antigens, and the degree of mismatch. Here we summarize the evidence for the role of DSA in the development of primary graft failure in haploidentical transplantation and provide consensus recommendations from the European Society for Blood and Marrow Transplant Group on testing, monitoring, and treatment of patients with DSA receiving haploidentical hematopoietic progenitor cell transplantation.

Background The use of post-transplant cyclophosphamide (PTCy) is highly effective in preventing graft-versus-host disease (GVHD) in the haploidentical (Haplo) transplant setting and is being increasingly used in matched sibling (MSD) and matched unrelated (MUD) transplants. There is no information on the impact of donor types using homogeneous prophylaxis with PTCy. Methods We retrospectively compared outcomes of adult patients with acute myeloid leukemia (AML) in first complete remission (CR1) who received a first allogeneic stem cell transplantation (SCT) with PTCy as GVHD prophylaxis from MSD ( n = 215), MUD ( n = 235), and Haplo ( n = 789) donors registered in the EBMT database between 2010 and 2017. Results The median follow-up was 2 years. Haplo-SCT carried a significantly increased risk of acute grade II–IV GVHD (HR 1.6; 95% CI 1.1–2.4) and NRM (HR 2.6; 95% CI 1.5–4.5) but a lower risk of relapse (HR 0.7; 95% CI 0.5–0.9) that translated to no differences in LFS (HR 1.1; 95% CI 0.8–1.4) or GVHD/relapse-free survival (HR 1; 95% CI 0.8–1.3). Interestingly, the use of peripheral blood was associated with an increased risk of acute (HR 1.9; 95% CI 1.4–2.6) and chronic GVHD (HR 1.7; 95% CI 1.2–2.4) but a lower risk of relapse (HR 0.7; 95% CI 0.5–0.9). Conclusions The use of PTCy in patients with AML in CR1 receiving SCT from MSD, MUD, and Haplo is safe and effective. Haplo-SCT had increased risk of acute GVHD and NRM and lower relapse incidence but no significant difference in survival.

Allogeneic haematopoietic stem cell transplantation (HSCT) for haematological malignancies can cause acute and chronic graft‐versus‐host disease (GvHD), impacting graft success and mortality. Rabbit anti‐thymocyte globulin (r‐ATG) or post‐transplant cyclophosphamide (PTCy) is effective in reducing GvHD in haploidentical‐HSCT. This review included 17 studies to assess rATG + PTCy for GvHD prophylaxis. Overall acute GvHD grade II‐IV, moderate‐to‐severe chronic GvHD and GvHD‐free relapse‐free survival rates ranged from 11.50%–35.40%, 2.90%–17.78% and 21.80%–63%, respectively. Although r‐ATG + PTCy treatment lowered GvHD incidence and increased survival rates, cytomegalovirus and Epstein–Barr virus reactivation were observed; therefore, more investigations on this treatment are needed, especially on dosing and timing when used for HSCT.

Background Compared with HLA-matched sibling donor (MSD) transplant, the outcomes of haploidentical donor (HID) transplant for refractory acute leukemia need to be further explored. In this study, we compared the outcomes of HID with MSD for refractory acute leukemia. Patients and methods This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Two hundred and seventy-eight patients with refractory acute leukemia were enrolled in this study, including 119 in HID group and 132 in MSD group. Sequential intensified conditioning was employed in all patients, and donor lymphocyte infusion (DLI) was administered in patients in the absence of active GVHD and according to minimal residual disease (MRD) from day + 60 post-transplantation for preventing relapse. Results The complete remission of leukemia by day + 30 post-transplant were 94% and 93%, respectively, in HID and MSD groups ( p = .802). The 1-year incidence of grades II–IV acute GVHD was 62% and 54% ( p = .025), and 3-year incidence of chronic GVHD was 55% and 55% ( p = .789), respectively, in two groups. HID transplant had lower incidence of first episode of MRD positivity and relapse than MSD transplant (28% vs 45%, p = .006; 26% vs 38%, p = .034). There was higher infection-related mortality in HID than MSD (8% vs 2%, p = .049) within the first 100 days’ post-transplant. The 5-year overall survival was 46% and 42% ( p = .832), respectively; the 5-year disease-free survival was 43% and 39% ( p = .665), in HID and MSD groups, respectively. Conclusions HID transplant has lower relapse, but higher infection-related mortality and similar survival rates in refractory acute leukemia by the strategy of sequential intensified conditioning followed by DLI compared with MSD transplant.

Posttransplant cyclophosphamide (PTCy) has revolutionized the landscape of human leukocyte antigen (HLA)-haploidentical hematopoietic cell transplantation (haplo-HCT), providing a pivotal therapeutic option for patients with hematological malignancies who lack an HLA-matched donor. In this retrospective analysis involving 54 adult patients undergoing PTCy-based haplo-HCT, we evaluated the impact of inhibitory killer immunoglobulin-like receptor (KIR)/HLA mismatch, alongside patient, donor, and transplant factors, on clinical outcomes within a homogeneous cohort characterized by a myeloablative conditioning regimen and bone marrow graft. With a median follow-up of 73.2 months, our findings reveal promising outcomes: 6-year overall survival, relapse-free survival, and graft-versus-host disease (GVHD) and relapse-free survival rates were 63% (95% CI: 51-79), 58% (95% CI: 46-74), and 42% (95% CI: 30-58), respectively. Notably, the cumulative incidence rates of relapse and non-relapse mortality at 6 years post-haplo-HCT were 29% (95% CI: 19-45) and 12% (95% CI: 6-26), respectively. Acute GVHD at day 100 posttransplantation occurred with a cumulative incidence of 33% (95% CI: 22- 49) for grades II-IV and 9% (95% CI: 3-23) for grades III-IV. Furthermore, 41% of patients developed chronic GVHD within 1 year posttransplantation, distributed as follows: 28% mild, 9% moderate, and 4% severe. Within our cohort, several variables were associated with outcomes following PTCy-based haplo-HCT. However, inhibitory KIR/HLA mismatch did not influence these outcomes.

Haploidentical related donor transplantation (haplo-HCT) is associated with cytokine release syndrome (CRS). We conducted a multicenter retrospective study to analyze risk factors for CRS and outcomes after haplo-HCT. We included 451 patients from four academic centers receiving both peripheral blood and bone marrow grafts. Severe CRS was more common with PB vs. BM grafts (19.5% vs 4.9%, OR 2.9, p = 0.05). Multivariable analysis identified recipient CMV sero-positivity, prior transplant, HCT-CI score and donor–recipient sex mismatch as risk factors for severe CRS. Outcomes were analyzed with no CRS as the comparison group. Overall survival (OS) was superior with mild CRS (HR 0.64, p = 0.05) and worst with severe CRS (HR 2.12, p = 0.0038). Relapse risk was significantly decreased in both mild CRS (HR 0.38, p < 0.0001) and severe CRS (HR 0.17, p < 0.0001) groups. The risk of non-relapse mortality was notably higher in severe CRS group (HR 8.0, p < 0.0001), but not in mild CRS group. Acute GVHD was similar among groups. Chronic GVHD at 1 year was 18.5% for no CRS, 23% for mild CRS, and 4.3% for severe CRS (p = 0.0023), with the competing risk of early mortality and short follow up of surviving patients contributing to the low chronic GVHD rates in the severe CRS group.

Background There is no information on the impact of donor type in allogeneic hematopoietic stem cell transplantation (HCT) using homogeneous graft-versus-host (GVHD) prophylaxis with post-transplant cyclophosphamide (PTCy) in acute lymphoblastic leukemia (ALL). Methods We retrospectively analyzed outcomes of adult patients with ALL in CR1 that had received HCT with PTCy as GVHD prophylaxis from HLA-matched sibling (MSD) ( n  = 78), matched unrelated (MUD) ( n  = 94) and haploidentical family (Haplo) ( n  = 297) donors registered in the EBMT database between 2010 and 2018. The median follow-up period of the entire cohort was 2.2 years. Results Median age of patients was 38 years (range 18–76). Compared to MSD and MUD, Haplo patients received peripheral blood less frequently. For Haplo, MUD, and MSD, the cumulative incidence of 100-day acute GVHD grade II–IV and III–IV, and 2-year chronic and extensive chronic GVHD were 32%, 41%, and 34% ( p  = 0.4); 13%, 15%, and 15% ( p  = 0.8); 35%, 50%, and 42% ( p  = 0.01); and 11%, 17%, and 21% ( p  = 0.2), respectively. At 2 years, the cumulative incidence of relapse and non-relapse mortality was 20%, 20%, and 28% ( p  = 0.8); and 21%, 18%, and 21% ( p  = 0.8) for Haplo, MUD, and MSD, respectively. The leukemia-free survival, overall survival and GVHD-free, relapse-free survival for Haplo, MUD, and MSD was 59%, 62%, and 51% ( p  = 0.8); 66%, 69%, and 62% ( p  = 0.8); and 46%, 44%, and 35% ( p  = 0.9), respectively. On multivariable analysis, transplant outcomes did not differ significantly between donor types. TBI-based conditioning was associated with better LFS. Conclusions Donor type did not significantly affect transplant outcome in patient with ALL receiving SCT with PTCy.

Letermovir (LTV) prophylaxis is effective in reducing the incidence of clinically significant cytomegalovirus (CMV) infection (cs CMVi) after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Since our centre began administering LTV prophylaxis in June 2022, we have observed a certain increase in the incidence of Epstein–Barr virus (EBV) reactivation after haploidentical HSCT. We retrospectively analysed 230 consecutive patients who underwent haploidentical HSCT with rabbit anti-thymocyte globulin (ATG) from October 2022 to June 2023. The LTV group included 133 patients who received LTV prophylaxis, and the control group included 97 patients who did not receive LTV prophylaxis. At 1 year after HSCT, EBV reactivation was observed in 36 patients (27%) in the LTV group and 13 patients (13%) in the control group ( p  = 0.012). All patients with EBV reactivation had EBV-DNAemia, and one patient in each group developed EBV-associated posttransplantation lymphoproliferative disorder (PTLD). The proportion of patients with low EBV-DNA loads (> 5 × 10 2 to < 1 × 10 4 copies/mL) was greater in the LTV group than in the control group (23% vs. 10%, p  = 0.01). The proportion of patients with CMV reactivation was lower in the LTV group than in the control group (35% vs. 56%, p  = 0.002). There was no significant difference between the groups in terms of neutrophil and platelet count recovery, the cumulative incidence of acute/chronic graft-versus-host disease, overall survival, cumulative relapse rate or nonrelapse mortality. Our results show that the increased incidence of EBV reactivation may be associated with LTV prophylaxis for CMV after haploidentical HSCT.

Hematopoietic stem cell transplantation from a haploidentical donor is increasingly used and has become a standard donor option for patients lacking an appropriately matched sibling or unrelated donor. Historically, prohibitive immunological barriers resulting from the high degree of HLA-mismatch included graft-vs.-host disease (GVHD) and graft failure. These were overcome with increasingly sophisticated strategies to manipulate the sensitive balance between donor and recipient immune cells. Three different approaches are currently in clinical use: (a) T-cell depletion resulting in grafts with defined immune cell content (b) extensive immunosuppression with a T-cell replete graft consisting of G-CSF primed bone marrow and PBSC (GIAC) (c) T-cell replete grafts with post-transplant cyclophosphamide (PTCy). Intriguing studies have recently elucidated the immunologic mechanisms by which PTCy prevents GVHD. Each approach uniquely affects post-transplant immune reconstitution which is critical for the control of post-transplant infections and relapse. NK-cells play a key role in haplo-HCT since they do not mediate GVHD but can successfully mediate a graft-vs.-leukemia effect. This effect is in part regulated by KIR receptors that inhibit NK cell cytotoxic function when binding to the appropriate HLA-class I ligands. In the context of an HLA-class I mismatch in haplo-HCT, lack of inhibition can contribute to NK-cell alloreactivity leading to enhanced anti-leukemic effect. Emerging work reveals immune evasion phenomena such as copy-neutral loss of heterozygosity of the incompatible HLA alleles as one of the major mechanisms of relapse. Relapse and infectious complications remain the leading causes impacting overall survival and are central to scientific advances seeking to improve haplo-HCT. Given that haploidentical donors can typically be readily approached to collect additional stem- or immune cells for the recipient, haplo-HCT represents a unique platform for cell- and immune-based therapies aimed at further reducing relapse and infections. The rapid advancements in our understanding of the immunobiology of haplo-HCT are therefore poised to lead to iterative innovations resulting in further improvement of outcomes with this compelling transplant modality.