A New Standard in Graft-versus-Host Disease Prophylaxis? An Introduction to Blood and Marrow Transplant Clinical Trials Network 1703

A prospective study of posttransplant cyclophosphamide for unrelated donor peripheral blood stem cell transplant with special attention to graft content and the impact of a higher γδ T cell dose

Posttransplant cyclophosphamide (PtCy) has been shown to decrease post-hematopoietic stem cell transplant acute and chronic graft-versus-host disease (GVHD). In this study, PtCy was used in 44 patients along with mycophenolate and tacrolimus with HLA matched (29) and mismatched (15) unrelated donors to determine the impact of graft content on outcome; thus, all patients had flow cytometric analysis of their graft content including the number of B cells, NK cells, and various T cell subsets. Higher γδ T cell dose was associated with the development of acute GVHD (p = .0038). For PtCy, further studies of the cell product along with further graft manipulation, such as selective γδ T cell depletion, could potentially improve outcomes.

Severity of Chronic Graft-versus-Host Disease and Late Effects Following Allogeneic Hematopoietic Cell Transplantation for Adults with Hematologic Malignancy

The study aimed to determine the association of chronic graft-versus-host disease (cGVHD) diagnosis and severity with the development of subsequent neoplasms (SN) and nonmalignant late effects (NM-LE) in 2-year disease-free adult survivors following hematopoietic cell transplantation (HCT) for a hematologic malignancy. To do so, we conducted a retrospective analysis of 3884 survivors of HCT for hematologic malignancy in the Center of International Blood and Marrow Transplant Research database. We conducted a landmark analysis at the 2-year post-transplantation date, comparing first SN and NM-LE in survivors with and without cGVHD. The cumulative incidence (CuI) of SN and NM-LE were estimated through 10 years post-HCT in both groups, with death or disease relapse as a competing risk. Cox proportional hazards models were used to evaluate the associations of cGVHD and its related characteristics with the development of SN and NM-LE. The estimated 10-year CuI of SN in patients with GVHD (n = 2669) and patients without cGVHD (n = 1215) was 15% (95% confidence interval [CI], 14% to 17%) versus 9% (7.2% to 11%) (P < .001). cGVHD by 2 years post-HCT was independently associated with SN (hazard ratio [HR], 1.94; 95% CI, 1.53 to 2.46; P < .0001) with a standardized incidence ratio of 3.2 (95% CI, 2.9 to 3.5; P < .0001). Increasing severity of cGVHD was associated with an increased risk of SN. The estimated 10-year CuI of first NM-LE in patients with and without cGVHD was 28 (95% CI, 26% to 30%) versus 13% (95% CI, 11% to 15%) (P < .001). cGVHD by 2 years post-HCT was independently associated with NM-LE (HR, 2.23; 95% CI, 1.81 to 2.76; P < .0001). Multivariate analysis of cGVHD-related factors showed that increasing severity of cGVHD, extensive grade, having both mucocutaneous and visceral involvement, and receiving cGVHD treatment for >12 months were associated with the greatest magnitude of risk for NM-LE. cGVHD was closely associated with both SN and NM-LE in adult survivors of HCT for hematologic malignancy. Patients identified as having more severe involvement and both mucocutaneous and visceral organ involvement may warrant enhanced monitoring and screening for SNs and NM-LEs. However, caution is warranted when interpreting these results, as patients with cGVHD may have more vigilant post-transplantation health care and surveillance for late effects.

Successful Outcome in Patients with Myelofibrosis Undergoing Allogeneic Donor Hematopoietic Cell Transplantation Using Reduced-Doses of Post-Transplant Cyclophosphamide: challenges and review of the literature

BACKGROUND

Engraftment and non-relapse mortality (NRM) greatly depend upon the transplant platform in patients with Myelofibrosis (MF).

OBJECTIVE

We report outcomes of 14 consecutive MF patients who received reduced doses of post-transplant Cyclophosphamide (PTCy) (60 mg/kg total dose) and tacrolimus as graft versus host disease (GVHD) prophylaxis as part of a new standardized allogeneic hematopoietic-cell transplantation (allo-HCT) protocol.

STUDY DESIGN

Median age at HCT was 59 years (range: 41-67), and median interval from diagnosis to HCT was 19 months (range: 2-114). All cases received ruxolitinib before HCT and 71% had no response. Most patients (78%) had symptomatic splenomegaly at HCT. Eighty-six percent received reduced-intensity conditioning (RIC) and most of them (64%) from an unrelated donor.

RESULTS

There were not graft failures and neutrophil and platelet recovery occurred at a median of 21 and 31 days. The cumulative incidence of grade II-IV and III-IV acute GVHD was 28.6% and 7%. The 2-year incidence of overall and moderate-severe chronic GVHD was 36% and 14%. Only 1 patient relapsed after transplant, and NRM at 100 days and 2-years was 7% and 14%. GVHD-free/relapse-free and immunosuppression free incidence at 1 year was 41%. With a median follow-up for survivors of 28 months (range:8-55), the 2-year overall survival and progression-free survival are 86% and 69%.

CONCLUSION

Reduced doses of PTCy as GVHD prophylaxis for high risk MF patients shows promising results by reducing GVHD incidence without cases of graft failure.

Post-Transplantation Cyclophosphamide Is Associated with an Increase in Non-Cytomegalovirus Herpesvirus Infections in Patients with Acute Leukemia and Myelodysplastic Syndrome

The use of post-transplantation cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis in recipients of haploidentical and fully matched transplantations is on the increase. Published studies have reported an increased incidence of cytomegalovirus (CMV) infection with the use of PTCy. Limited data exist on the incidence and outcomes of infection with non-CMV herpesviruses (NCHV) in this setting. The aim of this study was to evaluate the cumulative incidence of NCHV infections and the association of NCHV infections with transplantation-specific outcomes in recipients of haploidentical transplantation with PTCy (HaploCy), matched sibling donor transplantation with PTCy (SibCy), and matched sibling donor transplantation with calcineurin inhibitor-based prophylaxis (SibCNI). We hypothesized that, like CMV infection, HaploCy recipients of also will have a higher risk of NCHV infections. Using the Center for International Blood and Marrow Transplantation Research database, we analyzed 2765 patients (HaploCy, n = 757; SibCNI, n = 1605; SibCy, n = 403) who had undergone their first hematopoietic stem cell transplantation (HCT) between 2012 and 2017 for acute myelogenous leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome. The cumulative incidence of NCHV at 6 months post-NCT was 13.9% (99% confidence interval], 10.8% to 17.3%) in the HaploCy group, 10.7% (99% CI, 7.1% to 15%) in the SibCy group, and 5.7% (99% CI, 4.3% to 7.3%) in the Sib CNI group (P < .001). This was due primarily to a higher frequency of human herpesvirus 6 viremia reported in patients receiving PTCy. The incidence of Epstein-Barr viremia was low in all groups, and no cases of post-transplantation lymphoproliferative disorder were seen in either PTCy group. The incidence of NCHV organ disease was low in all 3 cohorts. The development of NCHV infection was associated with increased treatment-related mortality, particularly in the HaploCy group. There was no association with the development of GVHD, relapse, or disease-free survival. Patients in PTCy cohorts who did not develop NCHV infection had lower rates of cGVHD. This study demonstrates that the use of PTCy is associated with an increased risk of NCHV infection. The development of NCHV infection was associated with increased nonrelapse mortality, especially in the HaploCy group. Prospective trials should consider viral surveillance strategies in conjunction with assessment of immune reconstitution for a better understanding of the clinical relevance of viral reactivation in different HCT settings.

Cardiac Toxicity after Matched Allogeneic Hematopoietic Cell Transplantation in the Post-Transplant Cyclophosphamide Era

Graft-versus-host-disease (GVHD) is one of the leading causes of non-relapse mortality (NRM) following allogeneic hematopoietic cell transplantation (alloHCT). Post-transplant cyclophosphamide (PTCy) has shown promise in managing GVHD. However, cyclophosphamide has known cardiac toxicities and few studies have evaluated the cardiac toxicities that arise following PTCy. Here, we completed a retrospective analysis of matched alloHCT patients at our institution who received PTCy or non-PTCy-based GVHD prophylaxis, with the goal of determining the incidence of cardiac toxicities up to 100 days after alloHCT. We included 585 patients in our analysis and found that 38 patients (6.5%) experienced cardiac toxicities after alloHCT. The toxicities observed included arrhythmias (n=21), heart failure (n=14), pericardial effusions (n=10), and myocardial infarction or ischemia (n=7). Patients who received PTCy had a 7.4% incidence of cardiac toxicities, while non-PTCy patients had an incidence of 5.8% (p=0.4). We found that age > 55 years (p=0.02), history of hypertension (p=0.01), arrhythmia (p=0.003), diabetes (p=0.04), and cardiac comorbidities (p<0.001) were significant predictors of cardiac toxicity, while none of the preparative and GVHD prophylaxis regimens used were predictive of cardiac toxicity. From these findings, we proposed the use of a Cardiac Risk Stratification Score to quantify the risk of cardiac toxicity following alloHCT and found that a higher score correlated with cardiac toxicity incidence. Furthermore, the development of cardiac toxicity was associated with worse 1-yr overall survival (OS) and NRM while the use of PTCy was associated with improvements in 1-year OS and NRM rates.