MAGIC biomarkers predict long-term outcomes for steroid-resistant acute GVHD

High Amphiregulin Expression in Intestinal Biopsies of Pediatric Patients with Severe Acute Graft-Versus-Host Disease

Acute graft-versus-host disease (GvHD) is a major complication of hematopoietic cell transplantation (HCT). Despite of recent advances in prophylaxis, diagnosis and treatment it is still a serious cause of morbidity and mortality after HCT. Amphiregulin (AREG) is an epidermal growth factor receptor ligand known for restoring damaged intestinal tissue. AREG has been studied as a blood biomarker in acute GvHD and was found predictive of steroid response and mortality. However, the expression of AREG in intestinal tissue in pediatric patients with acute GvHD is unknown. The aim of this study is to analyze and evaluate AREG expression in intestinal tissue biopsies of pediatric patients with GvHD, in comparison to patients with inflammatory bowel disease (IBD) and a control group with no pathological findings to provide insights in the biological tissue expression of this potential diagnostic and prognostic biomarker. We performed a retrospective study with pediatric patients who had an intestinal biopsy performed after HCT between 2010 and 2021, patients who had a diagnosis of IBD and patients with normal findings at the University Children's Hospital Zurich. Intestinal biopsies were stained for AREG. We used a semi-quantitative score ranging from 0 (not present) to 3 (intense) to grade the AREG expression. The grading was performed by a pathologist blinded to the group allocation. Lerner scores were also performed. The median AREG scores between the groups were compared using multivariable linear regression with age and sex as confounders. The study protocol was approved by the Ethical committee of Canton Zürich, Switzerland, number 2022-01037. Overall, 59 biopsies were stained for AREG, 20 after HCT (6 patients with severe GvHD, 5 with mild GvHD and 9 without GvHD), 19 with IBD and 20 controls. The median for the AREG overall grade for control group was 2, for the HCT with severe GvHD group 2.5 (P = .060) and for the IBD group 2.5 (P = .007). The results for the AREG epithelium and lamina propria grades were similar. There were no differences in survival between patients with GvHD with overall AREG scores below and greater or equal to the median of 2.5. This study showed that AREG scores were higher in intestinal biopsies from patients with severe GvHD and IBD compared to controls and patients with mild or no GvHD. Consequently, AREG staining could potentially be used as an additional marker for severe inflammation as seen in GvHD and IBD.

Steroid Refractory Acute GVHD: The Hope for a Better Tomorrow

Steroid-refractory acute graft-versus-host disease (SR-AGVHD) presents a significant barrier to successful outcomes following allogeneic hematopoietic cell transplantation (HCT), despite advancements in GVHD prophylaxis and management. While ruxolitinib therapy has shown improved response rates, survival benefits remain elusive. This review explores the definitions and proposed distinct pathophysiology and treatment landscape of SR-AGVHD. Emerging therapies offer potential, yet further research is critical to better define steroid-refractory populations, improve treatment precision with biomarkers, and overcome resistance, particularly in ruxolitinib-refractory cases.

Plasma Nucleosome Levels and Risk of Acute Graft-Versus-Host Disease After Myeloablative Allogeneic Hematopoietic Stem Cell Transplantation: A Single-Center Cohort Study

Circulating nucleosomes are representative of cell death, which is a feature of acute graft-versus-host disease (GVHD) following allogeneic hematopoietic stem cell transplantation (allo-HSCT). We explored whether plasma nucleosome levels were prognostic for acute GVHD. We examined the level of circulating nucleosomes in 131 patients who underwent a myeloablative allo-HSCT between June 2015 and August 2018. The measurements were made using quantitative photometric sandwich-ELISA on stored plasma samples obtained pretransplantation (at a median of day -23) and around days +7, +14, and +28 after allo-HSCT. The median plasma nucleosome level remained constant until day +28, where they increased significantly (P < .001 compared to all other times of measurement). The plasma nucleosome level at day +28 was inversely associated with the risk of later grade II to IV acute GVHD (odds ratio [OR] 0.86 per 5 arbitrary unit [AU] increase [95% confidence intervals (CI): 0.66 to 0.99], P = .03), also after adjustment for risk factors of acute GVHD (OR 0.78 per 5 AU increase [95% CI: 0.56 to 0.96], P = .01). We found no support for an association between the plasma level of nucleosomes measured pretransplantation or around day +7 or +14 and the risk of subsequent grade II to IV acute GVHD. We observed a positive correlation between nucleosomes, suppressor of tumorigenesis 2, and C-reactive protein at day +28 (Spearman's ρ = 0.522, P < .001; and Spearman's ρ = 0.386, P < .001; respectively). A lower level of plasma nucleosomes at day +28 after HSCT was associated with a higher risk of subsequent acute GVHD. Additional studies are needed to validate circulating nucleosomes as a prognostic biomarker of acute GVHD.

Prediction and Prognostication of Acute Graft-Versus-Host Disease by MAGIC Biomarkers

Recent advancements in prophylaxis for acute graft-versus-host disease (GVHD) have successfully reduced the incidence of severe cases; however, overall survival rates have not significantly improved, and GVHD continues to be a major cause of mortality. The severity of gastrointestinal (GI) damage is especially critical, as it strongly correlates with treatment failure and non-relapse mortality, but clinical symptoms do not reliably predict peak severity in its early stages. Biomarker-based algorithms, such as the Mount Sinai Acute GVHD International Consortium (MAGIC) algorithm, leverage serum levels of GI GVHD biomarkers (ST2 and REG3α) to quantify intestinal crypt damage, providing more accurate predictions of GVHD outcomes compared to clinical assessments. Clinical trials have investigated the use of biomarkers as entry criteria for treatment, with notable success in guiding treatment de-escalation, which is increasingly important as the presentation of GVHD shifts towards milder forms. The recently developed MAGIC composite scores further enhance prediction accuracy by integrating clinical symptom severity with biomarker assessments. Future clinical trials that employ these composite scores or similar algorithms are anticipated to be more efficient by identifying patients who are most likely to benefit from specific therapies and ultimately improving the management of GVHD.

Teduglutide for treatment-refractory severe intestinal acute graft-versus-host disease - a multicenter survey

Intestinal glucocorticoid-refractory (SR) acute (a) graft-versus-host disease (GVHD) causes high non-relapse mortality (NRM) in patients after allogeneic hematopoietic cell transplantation (allo-HCT). Recent preclinical data indicate that acute GVHD causes a loss of intestinal neuroendocrine L-cells leading to reduced levels of glucagon-like peptide-2 (GLP-2). GLP-2 substitution improved GVHD severity and increased Paneth cells and intestinal stem cells in mice. This motivated us to treat patients with refractory intestinal aGHVD using the GLP-2-analogon teduglutide. In this retrospective multicenter survey, 17 patients received teduglutide as salvage-therapy for SR-intestinal aGVHD. The best response (CR or PR) at any time point during and after treatment was 64.7% (11/17) including 41.2% (7/17) CR and 23.5% (4/17) PR. At a median follow-up of 28 weeks after teduglutide 10/17 patients are alive. Most patients experienced an increase of the albumin serum level within 2 months after the first teduglutide dose, including patients who clinically did not respond to teduglutide treatment. No specific teduglutide-related toxicity was observed. Our retrospective analysis suggests that teduglutide is safe and has activity in a fraction of patients with intestinal SR-aGVHD, which needs validation in a prospective trial.

Oral beclomethasone dipropionate therapy and prognostic plasma biomarkers for gastrointestinal graft-versus-host disease

The real-world outcomes of oral beclomethasone dipropionate (BDP) for gastrointestinal graft-versus-host disease (GVHD) were evaluated in a single-center, prospective, observational study of 167 patients who developed histologically confirmed gastrointestinal GVHD. The median patient age was 55 years (range 10-71). The initial GVHD grade was mostly IIa (n = 138). BDP was used without systemic corticosteroids in 73 patients (44%), resulting in a decreased proportion of patients who received systemic corticosteroid administration from 76 to 58% (P = 0.001). The 4-week gastrointestinal response rate after BDP therapy, the primary endpoint, was 73% (95% CI 66-80%) compared with 68% (95% CI 55-78%) before BDP implementation. The proportion of patients with maximum gastrointestinal stage ≥ 2 was lower after than before BDP implementation (18% versus 35%, respectively, P = 0.004). The 1 year cumulative incidence of nonrelapse mortality (NRM) after gastrointestinal GVHD therapy was 15% after and 22% before BDP implementation (P = 0.12). The 4-week gastrointestinal response rate was lower in patients with elevated ST2 or REG3α levels than the remaining patients (36% versus 73%, P = 0.03). The 1 year NRM was higher in patients with elevated ST2 or ANG2 levels than the remaining patients (64% versus 12%, P < 0.001). This study characterized the outcomes of BDP therapy in real-world patients.

Budesonide, Added to PTCy-Based Regimen, for Prevention of Acute GI GVHD After Allogeneic Stem Cell Transplantation

Oral budesonide exerts local effects with negligible systemic glucocorticoid activity, due to rapid first-pass metabolism, therefore, could potentially be efficacious in preventing gastrointestinal (GI) acute GVHD (aGVHD). We explored the use of budesonide, added to posttransplant cyclophosphamide (PTCy), tacrolimus, and mycophenolate mofetil, for prevention of GI aGVHD after allogeneic hematopoietic stem cell transplantation (AHSCT) in a prospective observational study and treated 80 patients with a median age of 53 years (range 19-74). Results were compared with a publicly available CIBMTR dataset of 646 patients who received PTCy-based GVHD prophylaxis (CIBMTR Study # GV17-02) (control). Cumulative incidence (CI) of 3-month grade 2-4 and grade 3-4 aGVHD in the budesonide and control groups were 3.8% vs. 34.4% (p < 0.001) and 1.3% vs. 9.8% (p = 0.029), respectively. One-year GRFS (70.5% vs. 31.5%, p < 0.001), PFS (73.4% vs. 52.8%, p = 0.003), and OS (80.1% vs. 64.2%, p = 0.038) were significantly higher in the budesonide group compared with control group. Propensity score-adjusted analyses showed that the addition of budesonide significantly decreased risk of aGVHD grade 2-4 (HR 0.29, p < 0.001), grade 3-4 (HR 0.12, p = 0.045), and cGVHD (HR 0.22, p < 0.001), which resulted in better GRFS (HR 0.38, p < 0.001), PFS (HR 0.58, p = 0.012), and OS (HR 0.72, p = 0.044). Similar results were found when using propensity score-matched analysis restricted to recipients of haploidentical transplantation. In conclusion, addition of budesonide to PTCy-based GVHD prophylaxis is safe and effective in preventing severe acute GI GVHD with significantly improved GRFS. These results could facilitate transition to peripheral blood grafts for all allogeneic transplant recipients.

Whole-Blood Longitudinal Molecular Profiling Maps the Road of Graft Versus Host Disease (GVHD)

Background: Graft versus host disease (GVHD) and the graft versus tumor (GVT) effect after allogeneic hematopoietic cell transplantation (allo-HCT) result from complex interactions between the donor immune system and the recipient environment. High-temporal longitudinal monitoring might be necessary to identify triggering events of GVHD and GVT and to intercept these events before their occurrence. But it would require an overall considerable amount of blood by venipuncture, which is unfeasible in such a fragile population. Methods: In this study, we implemented a targeted multiplex microfluidics q-PCR-based transcriptional fingerprint assay (TFA) on 50 µL of blood collected by a simple fingerstick to evaluate post-allo-HCT systemic immune perturbations associated with the development of GVHD. Fluctuations of a panel of 264 genes were measured in 31 allo-HCT patients by frequent (weekly or biweekly) analysis of 50 µL serial blood samples. Cross-sectional and longitudinal analyses correlated with detailed clinical annotations were performed. Results: Signatures of neutrophil activation and interferon (IFN) characterized the onset of acute GVHD, while an ongoing cytotoxic response was modulated in chronic mild GVHD and protein-synthesis and B-cell-related signatures characterized late acute/overlap GVHD. An unexpected erythroid signature distinguished patients with acute and mild chronic GVHD. Conclusions: Our micro-invasive approach unveiled the molecular heterogeneity of GVHD and identified hierarchically important biological processes conducive to different forms of GVHD. These findings increase our understanding of GVHD and reveal potentially targetable alterations. This approach might be implemented clinically to intercept GVHD before its occurrence and to modulate therapeutic interventions accordingly.

Serial Clinical and Biomarker Monitoring during Graft-Versus-Host Disease Treatment Identifies Distinct Risk Strata Including an Ultra-Low Risk Group

BACKGROUND

The standard treatment for acute graft-vs-host disease (GVHD), a common complication following allogeneic hematopoietic cell transplant, remains prolonged courses of high dose corticosteroids. Previous attempts to decrease corticosteroid exposure during GVHD therapy failed because physicians lack the tools necessary to safely reduce and shorten therapy and fear loss of GVHD control in responding patients. Prior studies have shown that a serum biomarker risk score, the MAGIC algorithm probability (MAP), provided prognostic value within groups with similar clinical severity and that patients with GVHD that is Minnesota standard risk by clinical symptoms and who have a low MAP at the start of corticosteroid treatment represent a low risk group with good outcomes.

OBJECTIVE

This study tested the hypothesis that serial monitoring of GVHD symptoms and the MAP score in patients with low risk GVHD could provide further risk stratification, and would identify a subset with exceptionally low rates of failure with standard treatment, which we term ultra-low risk (ULR) GVHD who might benefit from reduced corticosteroid treatment.

STUDY DESIGN

Weekly monitoring of clinical symptoms and MAPs from initiation to day 14 of treatment was used to further divide 450 patients with low risk GVHD into groups with different outcomes, such as overall response rates at day 28 and non-relapse mortality at six-months.

RESULTS

310/450 low risk patients (69%) who achieved clinical response by day 14 and had low MAPs at days 7 and 14 constituted an ultra-low risk (ULR) group. that experienced a significantly higher overall response rate at day 28 (93% vs 50%, p<0.001) that was sustained to day 56 (84% vs 45%, p<0.001) and significantly lower six-month NRM (4% vs 13%, p<0.001) compared to the non-ULR patients. Patients who achieved clinical response by day 14 but who developed a high MAP during monitoring (n=20) experienced six-fold higher six-month NRM than the ULR group (25% vs 4%, p<0.001). Among 120 patients who did not achieve a clinical response by day 14, the overwhelming majority (n=112) who maintained low MAPs at both days 7 and 14 of treatment experienced six-fold lower NRM at six months compared to patients with a high MAP at either time point (8% vs 50%, p<0.001). The majority of deaths within the ULR group were due to infections in patients with complete and sustained control of GVHD symptoms while the majority of deaths in the non-ULR group were due to poorly controlled GVHD.

CONCLUSIONS

Serial monitoring during treatment can identify a large subset of patients by day 14 who achieve excellent GVHD control but remain at risk for treatment complications with standard treatment and who might be suitable candidates for testing abbreviated corticosteroid courses.

18F-FLT PET and Blood-based Biomarkers for Identifying Gastrointestinal Graft versus Host Disease after Allogeneic Cell Transplantation

Purpose To determine whether fluorine 18 (18F) fluorothymidine (FLT) PET imaging alone or combined with Mount Sinai Acute GVHD International Consortium (MAGIC) biomarkers could help identify subclinical gastrointestinal graft versus host disease (GI-GVHD) by day 100 following hematopoietic stem cell transplantation (HSCT). Materials and Methods 18F-FLT PET imaging was analyzed in a prospective pilot study (ClinicalTrials.gov identifier no. NCT01338987) with a primary end point of engraftment for a planned secondary end point identifying GI-GVHD. Regions of interest (ROIs) in the colon (1 cm3), jejunum (1 cm3), and ileum (1 cm3) were drawn in the area of greatest signal intensity within each segment of the GI tract by using software. Standardized uptake values (SUVs) were captured on day 28 following transplantation, along with MAGIC serum biomarkers and MAGIC algorithm probability (MAP) scores using MAGIC serum biomarkers collected at days 28-35. Results Among 20 participants (median age, 33.85 years [IQR: 28.65-39.25 years]; 11 female, nine male), seven presented with clinically diagnosed GI-GVHD by 100 days. Increased SUV was observed throughout the GI tract, most predominantly in the jejunum. Maximum and mean SUV by day 100 were significantly elevated in those with GI-GVHD (maximum SUV, 4.81; mean SUV, 3.73; n = 7) compared with those without (maximum SUV, 3.99; mean SUV, 2.56). MAP score (P = .02) was associated with acute GVHD on day 28 but not on day 100. Spearman correlation between maximum SUV in the jejunum and MAP score was r = 0.65 (P = .002). Conclusion These data suggest that 18F-FLT PET may help identify acute GI-GVHD after HSCT and could inform location in areas difficult to biopsy. Keywords: Transplantation, PET/CT, Bone Marrow, Abdomen/GI ClinicalTrials.gov identifier: NCT01338987 © RSNA, 2024.

Graft-Versus-Host Disease Mouse Models: A Clinical-Translational Perspective

A variety of graft-versus-host disease (GVHD) models have been developed in mice for the purpose of allowing laboratory investigation of the pathobiology, prevention, and treatment of GVHD in humans. While such models are crucial in advancing our knowledge in this field, there are some key limitations that need to be considered when translating laboratory discoveries into the clinical context. This chapter will discuss current clinical practices in transplantation and GVHD and the relative strengths and weaknesses of mouse models that attempt to replicate these states.

ST2 and Reg3α: Can they predict aGvHD, steroid refractoriness and transplant-related mortality in pediatric patients after HSCT?

BACKGROUND/AIM

There are several complications of hematopoietic stem cell transplantation. Without any doubt, most important of these is aGvHD that increases transplant-related mortality. The aim of this study is to investigate whether ST-2 and Reg3α levels measured at an early stage in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation can be individual biomarkers identifying future GvHD and predicting treatment response.

MATERIALS AND METHODS

From January 2019 to January 2021, 27 patients undergoing hematopoietic stem cell transplantation for primary immunodeficiency or hematopoietic diseases formed the study group. During their follow-up, the patients were classified into two groups as those developing and those not developing aGvHD. Nineteen healthy volunteers from a similar age group who needed their blood samples drawn for other reasons and who did not have any history of chronic disease, infection or medication use formed the control group. Blood samples of patients scheduled to have allogeneic HSCT were obtained before the administration of the preparative regimen, on Day +7 post-transplant and on the day of diagnosis if they developed aGvHD. Serum samples were stored at -20ºC until the day of processing. ST2 and Reg3α levels were measured using the ELISA method.

RESULTS

For patients who developed aGvHD (n = 13), ST2 levels obtained before the transplantation, on Day +7 post-transplant and on the day of aGvHD diagnosis (in patients developing GvHD) were significantly higher compared to the healthy Control Group (p-value <0.05). As regards to the samples obtained on the same days, ST2 levels did not differ significantly among patients who developed and those who did not develop GvHD (n = 14; p-value >0.05). ST2 levels of samples obtained on the days that acute skin and gastrointestinal tract GvHD developed did not differ significantly between these two groups (p-value >0.05). Reg3α levels of the pre-transplant samples, on Day +7 after the transplantation and on the day of aGvHD diagnosis did not show any difference between any of the groups (p-value >0.05). As only two patients died after transplantation, thus correlation of ST2 and Reg3α levels with transplant-related mortality could not be proven.

CONCLUSION

The results of this study suggest that ST2 and Reg3α levels are neither diagnostic nor prognostic or predictive biomarkers of aGvHD, steroid resistance or transplant-related mortality in pediatric patients. This study can be regarded as a pilot study because of the small patient population; more research involving a larger patient population is required.

Cytokines in hematopoietic cell transplantation and related cellular therapies

Cytokines are pleiotropic molecules involved in hematopoiesis, immune responses, infections, and inflammation. They play critical roles in hematopoietic cell transplantation (HCT) and immune effector cell (IEC) therapies, mediating both therapeutic and adverse effects. Thus, cytokines contribute to the immunopathology of graft-versus-host disease (GVHD), cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). This review examines cytokine functions in these contexts, their influence on engraftment and immune recovery post-transplantation, and their role in mediating toxicities. We focus on current and potential uses of cytokines to enhance engraftment and potentiate IEC therapies, as well as strategies to mitigate cytokine-mediated complications using cytokine blockers (e.g., tocilizumab, anakinra) and JAK inhibitors (e.g., ruxolitinib). We discuss new insights into GVHD physiology that have led to novel treatments, such as CSF1R blockade, which is effective in refractory chronic GVHD.

Incidence, risk factors and therapy response of acute graft-versus-host disease after myeloablative hematopoietic stem cell transplantation with posttransplant cyclophosphamide

Posttransplant cyclophosphamide, sirolimus and mycophenolate mofetil (PTCy/siro/MMF) constitutes an innovative and well-tolerated acute graft-versus-host disease (aGVHD) prophylaxis after allogeneic stem cell transplantation (allo-HSCT), but risk factors for aGVHD incidence and therapy failure in this setting are scarce. This study prospectively registered all consecutive adult patients with hematologic malignancies who received a myeloablative allo-HSCT using PTCy/siro/MMF prophylaxis at our institution between 2017 and 2023. A total of 385 patients were included, of whom 44%, 34% and 22% were transplanted from matched sibiling, matched unrelated and haploidentical donors, respectively. The 180-day cumulative incidence of aGVHD was 21% (95% confidence interval [CI] 17-25%) for grade II-IV and 11% (95% CI 8-14%) grade III-IV aGVHD. The use of haploidentical donors was associated with an increased risk of severe aGVHD. Among 75 patients receiving first-line systemic corticosteroids, 49% achieved a sustained complete response, while 23% and 24% developed steroid-dependent (SD-aGVHD) and steroid-refractory aGVHD (SR-aGVHD), respectively. SR-aGVHD was associated with worse salvage treatment response and overall survival compared to SD-aGVHD. The 1-year cumulative incidence of aGVHD-related mortality was 5.4% (95% CI, 3.3-8.1). Risk factors for aGVHD-related mortality included haploidentical donors, older donors, diagnosis of myeldysplastic neoplasms, and grade IV aGVHD. This study confirms a low incidence aGVHD with PTCy/siro/MMF prophylaxis. SR-aGVHD showed poorer response to salvage therapies and worse survival, while haploidentical donors and older donor age were negative predictors for aGVHD-related deaths.

Differences in Acute Graft-Versus-Host Disease (GVHD) Severity and Its Outcomes Between Black and White Patients

Acute graft-versus-host disease (GVHD) is a significant complication following hematopoietic stem cell transplantation (HCT). Although recent advancements in GVHD prophylaxis have resulted in successful HCT across HLA barriers and expanded access to HCT for racial minorities, less is known about how race affects the severity and outcomes of acute GVHD. This study examines differences in the clinical course of acute GVHD and the prognostic value of GVHD biomarkers for Black and White recipients. We conducted a retrospective analysis of patients in the Mount Sinai Acute GVHD International Consortium (MAGIC) database who underwent HCT between 2014 and 2021 to describe the difference in clinical course of acute GVHD and significance of GVHD biomarkers between Black and White recipients. We used propensity score matching to generate a 1:3 matched cohort of 234 Black patients and 702 White patients with similar baseline characteristics. In the first year after HCT Black patients experienced a higher cumulative incidence of grade III-IV acute GVHD (17% versus 12%, P = 0.050), higher nonrelapse mortality (NRM; 18% versus 12%, P = .009), and lower overall survival that trended toward statistical significance (73% versus 79%, P = .071) compared to White patients. The difference in NRM in the first year was even greater among Black patients who developed GVHD than White patients (24% versus 14%, P = .041). The distribution of low, intermediate, and high MAGIC biomarker scores at the time of treatment was similar across racial groups (P = .847), however, Black patients with high biomarker scores experienced significantly worse NRM than White patients (71% versus 32%, P = .010). Our data indicate that Black patients are at a higher risk of NRM following HCT, primarily from a higher incidence of severe GVHD. Serum biomarkers at treatment initiation can stratify patients for risk of NRM across races, however Black patients with high biomarker scores had a significantly greater NRM risk. These results suggest a need for strategies that mitigate the higher risk for poor GVHD outcomes among Black patients.

Gastrointestinal involvement refines prognosis in minnesota standard risk acute graft-vs.-host disease

Minnesota acute graft versus host disease (AGVHD) risk score is a validated tool to stratify newly-diagnosed patients into standard-risk (SR) and high-risk (HR) groups with ~85% having SR AGVHD. We aimed to identify factors for further risk-stratification within Minnesota SR patients. A single-center, retrospective analysis of consecutive patients between 1/2010 and 12/2014 was performed. Patients who developed AGVHD within 100 days and treated with systemic corticosteroids were included (N = 416), 356 (86%) of which were Minnesota SR and 60 (14%) had HR AGVHD. Isolated upper gastrointestinal (GI) AGVHD patients had significantly better day 28 and 56 CR/PR rates (90% vs. 72%, p = 0.004) and (83% vs 66%, p = 0.01), respectively, and lower 1-year non-relapse mortality (NRM; 10% vs. 22%; HR 0.4, p = 0.03). Lower GI AGVHD had less favorable outcomes with 1-year NRM of 40% (HR 2.1, p = 0.001), although CR/PR rates were not statistically different. In multivariate analysis, lower GI involvement (HR 2.6, p < 0.001), age ≥ 50 (HR 2.9, p < 0.001) and HCT-CI > 3 (HR 2.1, p = 0.002) predicted for 1-year NRM. Heterogeneity within Minnesota SR patients requires consideration in clinical trials, as distinct outcomes are observed in those with isolated upper GI and lower GI AGVHD, highlighting the importance of stratification in clinical trial design.

Interventions to reduce the risk of side-effects of cancer treatments in childhood

INTRODUCTION

Childhood cancers as a group affect around 1 in 500 children but each individual diagnosis is a rare disease. While research largely focuses on improving cure rates, the management of side effects of treatment are high priority for clinicians, families and children and young people.

AREAS COVERED

The prevention and efficient management of infectious complications, oral mucositis, nausea and vomiting and graft-vs-host disease illustrated with examples of implementation research, translation of engineering to care, advances in statistical methodologies, and traditional bench-to-patient development. The reviews draw from existing systematic reviews and well conducted clinical practice guidelines.

EXPERT OPINION

The four areas are driven from patient and family priorities. Some of the problems outlined are ready for proven interventions, others require us to develop new technologies. Advancement needs us to make the best use of new methods of applied health research and clinical trial methodologies. Some of the greatest challenges may be those we're not fully aware of, as new therapies move from their use in adult oncological practice into children. This will need us to continue our collaborative, multi-professional, multi-disciplinary and eclectic approach.

Regenerating Family Member 3 Alpha Is Predictive of Mortality Following Emergent Large Vessel Occlusion

Regenerating Family Member 3 Alpha (REG3A) is an antimicrobial protein secreted by the intestine and pancreas with additional immunomodulatory properties. Previously, we published that REG3A expression in ischemic stroke patient systemic blood, during mechanical thrombectomy (MT), is significantly associated with inflammatory cytokines and patient function on admission. This paper, however, did not investigate post-acute death rates. Therefore, we investigated plasma REG3A protein expression, during MT, in patients (n = 141) that survived or died within the end of the follow-up after MT. Subjects who died had significantly higher systemic plasma REG3A levels at the time of MT compared to survivors (p = 0.001). Age, sex, time from last known normal, and admission NIHSS were included as predictors to control for confounding variables and were all examined to determine their association in patient mortality. Logistic regression was used to demonstrate that higher odds of death were associated with increased REG3A levels (p = 0.002). REG3A demonstrated acceptable discrimination (AUC (95% CI): 0.669 (0.566-0.772) in predicting mortality. The overall model with age, sex, time from last known normal, and admission NIHSS discriminated well between survivors and those who died (AUC (95% CI): 0.784 (0.703-0.864)). In conclusion, REG3A could be promising as a biomarker to prognosticate stroke outcomes and stratify high-risk groups following acute ischemic stroke.

Monocytes as an early risk factor for acute graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

Acute graft-versus-host disease (aGVHD) is a major complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and contributes to high morbidity and mortality. However, our current understanding of the development and progression of aGVHD after allo-HSCT remains limited. To identify the potential biomarkers for the prevention and treatment of aGVHD during the early hematopoietic reconstruction after transplantation, we meticulously performed a comparative analysis of single-cell RNA sequencing data from post-transplant patients with or without aGVHD. Prior to the onset of aGVHD, monocytes in the peripheral blood of patients with aGVHD experienced a dramatic rise and activation on day 21 post-transplantation. This phenomenon is closely aligned with clinical cohort results obtained from blood routine examinations. Furthermore, in vitro co-culture experiments showed that peripheral blood monocytes extracted from patients with aGVHD approximately 21 days post-transplantation induced a significantly higher proliferation rate of allogeneic T cells compared to those from patients without aGVHD. Our study indicates that monocytes could be a crucial early clinical risk factor for the development of aGVHD, and this insight could potentially guide the timing of monitoring efforts, recommending assessments at the pivotal juncture of approximately day 21 post-transplantation, shedding fresh light on the significance of early hematopoietic regeneration in relation to the onset of aGVHD.

New investigational drugs for steroid-refractory acute graft-versus-host disease: a review of the literature

INTRODUCTION

Steroid-refractory acute graft-versus-host disease (SR-aGVHD) remains a formidable obstacle in the field of allogeneic hematopoietic cell transplantation (allo-HCT), significantly contributing to patient morbidity and mortality. The current therapeutic landscape for SR-aGVHD is limited, often yielding suboptimal results, thereby emphasizing the urgent need for innovative and effective treatments.

AREAS COVERED

In light of the pivotal REACH2 trial, ruxolitinib phosphate, a Janus kinase inhibitor, has gained prominence as the standard treatment for SR-aGVHD. Nevertheless, a considerable number of patients either do not respond to or cannot tolerate this therapy. This review delves into emerging treatments for SR-aGVHD, including mesenchymal stromal cells (MSCs), fecal microbiota transplantation (FMT), CD3/CD7 blockade, neihulizumab, begelomab, tocilizumab, and vedolizumab. While some of these agents have shown encouraging results in early-phase trials, issues such as treatment-related toxicities and inconsistent responses in larger studies highlight the necessity for ongoing research.

EXPERT OPINION

Current trials exploring new agents and combination therapies offer hope for fulfilling the unmet clinical needs in SR-aGVHD, potentially leading to more effective and precise treatment strategies.

The MAGIC algorithm probability predicts treatment response and long-term outcomes to second-line therapy for acute GVHD

ABSTRACT

The significance of biomarkers in second-line treatment for acute graft-versus-host disease (GVHD) has not been well characterized. We analyzed clinical data and serum samples at the initiation of second-line systemic treatment of acute GVHD from 167 patients from 17 centers of the Mount Sinai Acute GVHD International Consortium (MAGIC) between 2016 and 2021. Sixty-two patients received ruxolitinib-based therapy, whereas 102 received other systemic agents. In agreement with prospective trials, ruxolitinib resulted in a higher day 28 (D28) overall response Frate than nonruxolitinib therapies (55% vs 31%, P = .003) and patients who received ruxolitinib had significantly lower nonrelapse mortality (NRM) than those who received nonruxolitinib therapies (point estimates at 2-year: 35% vs 61%, P = .002). Biomarker analyses demonstrated that the benefit from ruxolitinib was observed only in patients with low MAGIC algorithm probabilities (MAPs) at the start of second-line treatment. Among patients with a low MAP, those who received ruxolitinib experienced significantly lower NRM than those who received nonruxolitinib therapies (point estimates at 2-year: 12% vs 41%, P = .016). However, patients with high MAP experienced high NRM regardless of treatment with ruxolitinib or nonruxolitinib therapies (point estimates at 2-year: 67% vs 80%, P = .65). A landmark analysis demonstrated that the relationship between the D28 response and NRM largely depends on the MAP level at the initiation of second-line therapy. In conclusion, MAP measured at second-line systemic treatment for acute GVHD predicts treatment response and NRM. The outcomes of patients with high MAP are poor regardless of treatment choice, and ruxolitinib appears to primarily benefit patients with low MAP.

A Validated Risk Stratification That Incorporates MAGIC Biomarkers Predicts Long-Term Outcomes in Pediatric Patients with Acute GVHD

Acute graft versus host disease (GVHD) is a common and serious complication of allogeneic hematopoietic cell transplantation (HCT) in children but overall clinical grade at onset only modestly predicts response to treatment and survival outcomes. Two tools to assess risk at initiation of treatment were recently developed. The Minnesota risk system stratifies children for risk of nonrelapse mortality (NRM) according to the pattern of GVHD target organ severity. The Mount Sinai Acute GVHD International Consortium (MAGIC) algorithm of 2 serum biomarkers (ST2 and REG3α) predicts NRM in adult patients but has not been validated in a pediatric population. We aimed to develop and validate a system that stratifies children at the onset of GVHD for risk of 6-month NRM. We determined the MAGIC algorithm probabilities (MAPs) and Minnesota risk for a multicenter cohort of 315 pediatric patients who developed GVHD requiring treatment with systemic corticosteroids. MAPs created 3 risk groups with distinct outcomes at the start of treatment and were more accurate than Minnesota risk stratification for prediction of NRM (area under the receiver operating curve (AUC), .79 versus .62, P = .001). A novel model that combined Minnesota risk and biomarker scores created from a training cohort was more accurate than either biomarkers or clinical systems in a validation cohort (AUC .87) and stratified patients into 2 groups with highly different 6-month NRM (5% versus 38%, P < .001). In summary, we validated the MAP as a prognostic biomarker in pediatric patients with GVHD, and a novel risk stratification that combines Minnesota risk and biomarker risk performed best. Biomarker-based risk stratification can be used in clinical trials to develop more tailored approaches for children who require treatment for GVHD.

Treatment Patterns and Clinical Outcomes of Patients with Moderate to Severe Acute Graft-Versus-Host Disease: A Multicenter Chart Review Study

Acute graft-versus-host disease (aGVHD) remains a barrier to successful allogeneic hematopoietic stem cell transplantation (HSCT) outcomes. Contemporary comprehensive analyses of real-world clinical outcomes among patients who develop aGVHD post-HSCT are needed to better understand the unmet needs of this patient population. This multicenter, retrospective chart review describes treatment patterns and clinical outcomes among patients (≥18 years old) from Finland, Sweden, and France who developed grades II-IV aGVHD after their first HSCT (January 2016-June 2017). From 13 participating centers, 151 patients were included. The median (Q1, Q3) age at HSCT was 56 (45, 62) years old. One line of aGVHD treatment was received by 47.7%, and the most common first-line treatment was methylprednisolone (alone or in a combination regimen, 74.2%; monotherapy, 25.8%). Among patients treated with methylprednisolone, 79.5% achieved a complete or partial response. The median (Q1, Q3) number of treatment lines was 2.0 (1.0, 3.0). The median (Q1, Q3) time to obtain an aGVHD diagnosis from transplant was 29.5 (21.0, 44.0) days, and 14.5 (7.0, 34.0) days to achieve the best response for 110 evaluable patients. At 6 and 12 months, 53.6% and 49.0%, respectively, achieved a complete response. Chronic GVHD occurred in 37.7% of patients, and aGVHD reoccurred in 26.5%. Following aGVHD diagnosis, mortality rates were 30.0% at 6 months and 37.3% at 12 months. Findings from this study demonstrate a continuing unmet need for new therapies that control aGVHD and improve mortality.

Failure to launch commercially-approved mesenchymal stromal cell therapies: what's the path forward? Proceedings of the International Society for Cell & Gene Therapy (ISCT) Annual Meeting Roundtable held in May 2023, Palais des Congrès de Paris, Organized by the ISCT MSC Scientific Committee

Mesenchymal stromal cells (MSCs) are promising cell therapy candidates, but their debated efficacy in clinical trials still limits successful adoption. Here, we discuss proceedings from a roundtable session titled "Failure to Launch Mesenchymal Stromal Cells 10 Years Later: What's on the Horizon?" held at the International Society for Cell & Gene Therapy 2023 Annual Meeting. Panelists discussed recent progress toward developing patient-stratification approaches for MSC treatments, highlighting the role of baseline levels of inflammation in mediating MSC treatment efficacy. In addition, MSC critical quality attributes (CQAs) are beginning to be elucidated and applied to investigational MSC products, including immunomodulatory functional assays and other potency markers that will help to ensure product consistency and quality. Lastly, next-generation MSC products, such as culture-priming strategies, were discussed as a promising strategy to augment MSC basal fitness and therapeutic potency. Key variables that will need to be considered alongside investigations of patient stratification approaches, CQAs and next-generation MSC products include the specific disease target being evaluated, route of administration of the cells and cell manufacturing parameters; these factors will have to be matched with postulated mechanisms of action towards treatment efficacy. Taken together, patient stratification metrics paired with the selection of therapeutically potent MSCs (using rigorous CQAs and/or engineered MSC products) represent a path forward to improve clinical successes and regulatory endorsements.

Flares of acute graft-versus-host disease: a Mount Sinai Acute GVHD International Consortium analysis

ABSTRACT

The absence of a standardized definition for graft-versus-host disease (GVHD) flares and data on its clinical course are significant concerns. We retrospectively evaluated 968 patients across 23 Mount Sinai Acute GVHD International Consortium (MAGIC) transplant centers who achieved complete response (CR) or very good partial response (VGPR) within 4 weeks of treatment. The cumulative incidence of flares within 6 months was 22%, and flares were associated with a higher risk of nonrelapse mortality (NRM; adjusted hazard ratio [aHR], 4.84; 95% confidence interval [CI], 3.19-7.36; P < .001). Flares were more severe (grades 3/4, 41% vs 16%; P < .001) and had more frequent lower gastrointestinal (LGI) involvement (55% vs 32%; P < .001) than the initial GVHD. At CR/VGPR, elevated MAGIC biomarkers predicted the future occurrence of a flare, along with its severity and LGI involvement. In multivariate analyses, higher Ann Arbor (AA) biomarker scores at CR/VGPR were significant risk factors for flares (AA2 vs AA1: aHR, 1.81 [95% CI, 1.32-2.48; P = .001]; AA3 vs AA1: aHR, 3.14 [95% CI, 1.98-4.98; P < .001]), as were early response to initial treatment (aHR, 1.84; 95% CI, 1.21-2.80; P = .004) and HLA-mismatched unrelated donor (aHR, 1.74; 95% CI, 1.00-3.02; P = .049). MAGIC biomarkers also stratified the risk of NRM both at CR/VGPR and at the time of flare. We conclude that GVHD flares are common and carry a significant mortality risk. The occurrence of future flares can be predicted by serum biomarkers that may serve to guide adjustment and discontinuation of immunosuppression.

A Day 14 Endpoint for Acute GVHD Clinical Trials

The overall response rate (ORR) 28 days after treatment has been adopted as the primary endpoint for clinical trials of acute graft versus host disease (GVHD). However, physicians often need to modify immunosuppression earlier than day (D) 28, and non-relapse mortality (NRM) does not always correlate with ORR at D28. We studied 1144 patients that received systemic treatment for GVHD in the Mount Sinai Acute GVHD International Consortium (MAGIC) and divided them into a training set (n=764) and a validation set (n=380). We used a recursive partitioning algorithm to create a Mount Sinai model that classifies patients into favorable or unfavorable groups that predicted 12 month NRM according to overall GVHD grade at both onset and D14. In the Mount Sinai model grade II GVHD at D14 was unfavorable for grade III/IV GVHD at onset and predicted NRM as well as the D28 standard response model. The MAGIC algorithm probability (MAP) is a validated score that combines the serum concentrations of suppression of tumorigenicity 2 (ST2) and regenerating islet-derived 3-alpha (REG3α) to predict NRM. Inclusion of the D14 MAP biomarker score with the D14 Mount Sinai model created three distinct groups (good, intermediate, poor) with strikingly different NRM (8%, 35%, 76% respectively). This D14 MAGIC model displayed better AUC, sensitivity, positive and negative predictive value, and net benefit in decision curve analysis compared to the D28 standard response model. We conclude that this D14 MAGIC model could be useful in therapeutic decisions and may offer an improved endpoint for clinical trials of acute GVHD treatment.

Pediatric transplant-associated thrombotic microangiopathy health care utilization and implications of eculizumab therapy

ABSTRACT

The health care use (HCU) burden of transplant-associated thrombotic microangiopathy (TA-TMA) and its treatments are unknown. The objective of this study was to investigate inpatient costs associated with meeting criteria for TA-TMA in the first year after hematopoietic cell transplant (HCT). This institutional review board-approved retrospective multicenter study included serial children who underwent HCT from 1 January 2015 to 1 July 2019. A standardized unit cost (adjusted for geographic location, differences in cost of living, and inflation) for inpatient hospitalization was extracted from the Pediatric Health Information System data and linked to clinical data. Both total cost and cost per day from 15 days before stem cell infusion to 1-year after HCT were calculated. Among allogeneic (allo) transplant recipients, after adjusting for severe grade 3/4 acute graft-versus-host disease (GVHD), infections, and HLA mismatch, costs were not different in TA-TMA (n = 137) vs no TA-TMA (n = 238). Severe GVHD was significantly associated with increased costs. Among allo high-risk (HR) TMA-TMA, unadjusted costs were significantly higher in the eculizumab-treated cohort (n = 19) than in the supportive care group (n = 36). However, after adjusting for gastrointestinal bleeding that occurred disproportionately in the eculizumab (n = 6) vs supportive care (n = 0) cohort, eculizumab treatment was not associated with increased total costs. More studies are needed to determine the etiology of increased HCU costs in those with HR-TA-TMA and predict those more likely to benefit from eculizumab, reducing HCU and improving outcomes.

Unlocking protein-based biomarker potential for graft-versus-host disease following allogenic hematopoietic stem cell transplants

Despite the numerous advantages of allogeneic hematopoietic stem cell transplants (allo-HSCT), there exists a notable association with risks, particularly during the preconditioning period and predominantly post-intervention, exemplified by the occurrence of graft-versus-host disease (GVHD). Risk stratification prior to symptom manifestation, along with precise diagnosis and prognosis, relies heavily on clinical features. A critical imperative is the development of tools capable of early identification and effective management of patients undergoing allo-HSCT. A promising avenue in this pursuit is the utilization of proteomics-based biomarkers obtained from non-invasive biospecimens. This review comprehensively outlines the application of proteomics and proteomics-based biomarkers in GVHD patients. It delves into both single protein markers and protein panels, offering insights into their relevance in acute and chronic GVHD. Furthermore, the review provides a detailed examination of the site-specific involvement of GVHD. In summary, this article explores the potential of proteomics as a tool for timely and accurate intervention in the context of GVHD following allo-HSCT.

Easix Score Correlates With Endothelial Dysfunction Biomarkers and Predicts Risk of Acute Graft-Versus-Host Disease After Allogeneic Transplantation

Plasma biomarkers of endothelial dysfunction have been postulated for the diagnosis and prognosis of acute graft-versus-host disease (aGVHD). However, their use is not validated in clinical practice yet. The endothelial activation and stress index (EASIX), a simple score based on routine laboratory parameters, is considered to be an indirect marker of endothelial damage. High value of EASIX was correlated with worse non-relapse mortality (NRM) and overall survival (OS) and a high risk of sinusoidal obstructive syndrome and transplant-associated thrombotic microangiopathy (TA-TMA). This study investigates the predictive value of plasma biomarkers and the EASIX score for the prediction of aGVHD. We assessed vascular cell adhesion molecule-1 (VCAM-1), tumor necrosis factor receptor 1 (TNFR1), and VWF:Ag plasma levels and the EASIX score before allogeneic hematopoietic stem cell transplantation (allo-HSCT) and on days 0, 3, 7, 14, and 21 in an experimental cohort (n = 33). EASIX was transformed to a base-2 logarithm to perform the analysis. For the most relevant biomarkers, we estimate the optimal cutoff values and the discriminatory ability to differentiate patients with high-risk of aGVHD. The conclusions obtained in the experimental cohort were validated in a large cohort of 321 patients at the same institution. Plasma biomarkers and EASIX showed similar post-transplantation dynamics consisting of a progressive increase. Multivariate analysis showed an association between high TNFR1 levels and Log-2 EASIX score on day 7 after transplantation with an increased likelihood of developing aGVHD (hazard ratio [HR] = 1, P = .002; HR = 2.31, P = .013, respectively). Patients with TNFR1 ≥1300 ng/mL (HR = 7.19, P = .006) and Log2-EASIX ≥3 (HR = 14.7, P <.001) at day 7 after transplantation were more likely to develop aGVHD with high predictive accuracy (C-index of 74% and 81%, respectively). In the validation cohort, patients with Log2-EASIX ≥3 on day 7 after transplantation presented a significantly higher incidence of grade II-IV aGVHD (HR = 1.94, P = .004) independent of GVHD prophylaxis (HR = 0.38, P = .004), conditioning regimen (HR = 0.59, P =.02) and type of donor (HR = 2.38, P = .014). Differential degree of endothelial damage can be measured using both EASIX score and plasma biomarkers in the early post-transplantation period. Patients at risk of developing aGVHD could be easily identified by a high EASIX score. Both indicators of endothelial activation represent a promising approach to predict aGVHD.

Acute Steroid-Refractory Gastrointestinal Graft-Versus-Host Disease Is Not Associated With Significant Differences in Gut Taxonomic Composition Compared to Steroid-Sensitive Gastrointestinal Graft-Versus-Host Disease Immediately Before Onset of Disease

Taxonomic composition of the gut microbiota at the time of neutrophil engraftment is associated with the development of acute gastrointestinal graft-versus-host disease (GI GVHD) in patients undergoing allogeneic hematopoietic stem cell transplantation. However, less is known about the relationship between the gut microbiota and development of steroid-refractory GI GVHD immediately before the onset of disease. Markers of steroid-refractory GI GVHD are needed to identify patients who may benefit from the early initiation of non-corticosteroid-based GVHD treatment. Our aim was to identify differences in taxonomic composition in stool samples from patients without GVHD, with steroid-responsive GVHD and with steroid-refractory GI GVHD to identify predictive microbiome biomarkers of steroid-refractory GI GVHD. We conducted a retrospective case-control, single institution study, performing shotgun metagenomic sequencing on stool samples from patients with (n = 36) and without GVHD (n = 34) matched for time since transplantation. We compared the taxonomic composition of the gut microbiome in those with steroid-sensitive GI GVHD (n = 17) and steroid-refractory GI GVHD (n = 19) to each other and to those without GVHD. We also performed associations between steroid-refractory GI GVHD, gut taxonomic composition, and fecal calprotectin, a marker of GI GVHD to develop composite fecal markers of steroid-refractory GVHD before the onset of GI disease. We found that fecal samples within 30 days of GVHD onset from patients with and without GVHD or with and without steroid-refractory GI GVHD did not differ significantly in Shannon diversity (alpha-diversity) or in overall taxonomic composition (beta-diversity). Although those patients without GVHD had higher relative abundance of Clostridium spp., those with and without steroid-refractory GI GVHD did not significantly differ in taxonomic composition between one another. In our study, fecal calprotectin before disease onset was significantly higher in patients with GVHD compared to those without GVHD and higher in patients with steroid-refractory GI GVHD compared to steroid-sensitive GI GVHD. No taxa were significantly associated with higher levels of calprotectin.

Spatial transcriptomics reveals distinct tissue niches linked with steroid responsiveness in acute gastrointestinal GVHD

Severe acute graft-versus-host disease (aGVHD) is associated with significant mortality and morbidity, especially in steroid-resistant (SR) cases. Spatial transcriptomic technology can elucidate tissue-based interactions in vivo and possibly identify predictors of treatment response. Tissue sections from 32 treatment-naïve patients with biopsy-confirmed lower gastrointestinal (GI) aGVHD were obtained. The GeoMx digital spatial profiler was used to capture transcriptome profiles of >18 000 genes from different foci of immune infiltrates, colonic epithelium, and vascular endothelium. Each tissue compartment sampled showed 2 distinct clusters that were analyzed for differential expression and spatially resolved correlation of gene signatures. Classic cell-mediated immunity signatures, normal differentiated epithelial cells, and inflamed vasculature dominated foci sampled from steroid-sensitive cases. In contrast, a neutrophil predominant noncanonical inflammation with regenerative epithelial cells and some indication of angiogenic endothelial response was overrepresented in areas from SR cases. Evaluation of potential prognostic biomarkers identified ubiquitin specific peptidase 17-like (USP17L) family of genes as being differentially expressed in immune cells from patients with worsened survival. In summary, we demonstrate distinct tissue niches with unique gene expression signatures within lower GI tissue from patients with aGVHD and provide evidence of a potential prognostic biomarker.

Hepatic graft-versus-host disease: what we know, when to biopsy, and how to diagnose

Graft-versus-host disease (GVHD) is one of the serious complications that may develop after hematopoietic cell transplantation (HCT), for hematologic malignancies, solid organ transplantation, and other hematologic disorders. GVHD develops due to T lymphocytes present in the graft attacking the host antigens, which results in tissue damage. A significant number of HCT patients develop acute or chronic GVHD, which may affect multiple organs including the liver. The diagnosis of hepatic GVHD (hGVHD) is challenging as many other conditions in HCT patients may lead to liver dysfunction. Particularly challenging among the various conditions that give rise to liver dysfunction is differentiating sinusoidal obstruction syndrome and drug-induced liver injury (DILI) from hGVHD on clinical grounds and laboratory tests. Despite the minimal risks involved in performing a liver biopsy, the information gleaned from the histopathologic changes may help in the management of these very complex patients. There is a spectrum of histologic features found in hGVHD, and most involve histopathologic changes affecting the interlobular bile ducts. These include nuclear and cytoplasmic abnormalities including dysmorphic bile ducts, apoptosis, and cholangiocyte necrosis, among others. The hepatitic form of hGVHD typically shows severe acute hepatitis. With chronic hGVHD, there is progressive bile duct loss and eventually fibrosis. Accurate diagnosis of hGVHD is paramount so that timely treatment and management can be initiated. Techniques to prevent and lower the risk of GVHD from developing have recently evolved. If a diagnosis of acute GVHD is made, the first-line of treatment is steroids. Recurrence is common and steroid resistance or dependency is not unusual in this setting. Second-line therapies differ among institutions and have not been uniformly established. The development of GVHD, particularly hGVHD, is associated with increased morbidity and mortality.

Anandamide reduces the migration of lymphocytes to the intestine by CB2 activation and reduces TNF-α in the target organs, protecting mice from graft-versus-host disease

Graft-versus-host disease (GVHD) is a serious inflammatory illness that often occurs as a secondary complication of bone marrow transplantation. Current therapies have limited effectiveness and fail to achieve a balance between inflammation and the graft-versus-tumor effect. In this study, we investigate the effects of the endocannabinoid anandamide on the complex pathology of GVHD. We assess the effects of an irreversible inhibitor of fatty acid amine hydrolase or exogenous anandamide and find that they increase survival and reduce clinical signs in GVHD mice. In the intestine of GVHD mice, treatment with exogenous anandamide also leads to a reduction in the number of CD3+, CD3+CD4+, and CD3+CD8+ cells, which reduces the activation of CD3+CD4+ and CD3+CD8+ cells, as assessed by enhanced CD28 expression, a T cell co-stimulatory molecule. Exogenous AEA was also able to reduce TNF-α and increase IL-10 in the intestine of GVHD mice. In the liver, exogenous AEA reduces injury, TNF-α levels, and the number of CD3+CD8+ cells. Interestingly, anandamide reduces Mac-1α, which lowers the adhesion of transplanted cells in mesenteric veins. These effects are mimicked by JWH133-a CB2 selective agonist-and abolished by treatment with a CB2 antagonist. Furthermore, the effects caused by anandamide treatment on survival were related to the CB2 receptor, as the CB2 antagonist abolished it. This study shows the critical role of the CB2 receptor in the modulation of the inflammatory response of GVHD by treatment with anandamide, the most prominent endocannabinoid.

Novel therapies for graft versus host disease with a focus on cell therapies

Graft versus host disease (GVHD) can occur at any period post allogeneic hematopoietic stem cell transplantation as a common clinical complication contributing to significant morbidity and mortality. Acute GVHD develops in approximately 30-50% of patients receiving transplants from matched related donors. High doses of steroids are used as first-line treatment, but are unsuccessful in around 40% of patients, resulting in the diagnosis of steroid-refractory acute GVHD. Consensus has yet to develop for the management of steroid-refractory acute GVHD, and prognosis at six months has been estimated at around 50%. Thus, it is critical to find effective treatments that increase survival of steroid-refractory acute GVHD. This article describes the currently known characteristics, pathophysiology, and treatments for GVHD, with a special focus on recent advances in cell therapies. In particular, a novel cell therapy using decidua stromal cells (DSCs) was recently shown to have promising results for acute GVHD, with improved effectiveness over previous treatments including mesenchymal stromal cells. At the Karolinska Institute, severe acute GVHD patients treated with placenta-derived DSCs supplemented with either 5% albumin or 10% AB plasma displayed a one-year survival rate of 76% and 47% respectively. Furthermore, patients with steroid-refractory acute GVHD, displayed survival rates of 73% with albumin and 31% with AB plasma-supplemented DSCs, compared to the 20% survival rate in the mesenchymal stromal cell control group. Adverse events and deaths were found to be attributed only to complications of hematopoietic stem cell transplant and GVHD, not to the study intervention. ASC Therapeutics, Inc, in collaboration with the Karolinska Institute, will soon initiate a phase 2 multicenter, open-label study to further assess the efficacy and safety of intravenous DSC treatment in sixty patients with Grade II-IV steroid-refractory acute GVHD. This novel cell therapy represents a promising treatment to combat the poor prognosis that steroid-refractory acute GVHD patients currently face.

Chronic GvHD NIH Consensus Project Biology Task Force: evolving path to personalized treatment of chronic GvHD

Chronic graft-versus-host disease (cGvHD) remains a prominent barrier to allogeneic hematopoietic stem cell transplantion as the leading cause of nonrelapse mortality and significant morbidity. Tremendous progress has been achieved in both the understanding of pathophysiology and the development of new therapies for cGvHD. Although our field has historically approached treatment from an empiric position, research performed at the bedside and bench has elucidated some of the complex pathophysiology of cGvHD. From the clinical perspective, there is significant variability of disease manifestations between individual patients, pointing to diverse biological underpinnings. Capitalizing on progress made to date, the field is now focused on establishing personalized approaches to treatment. The intent of this article is to concisely review recent knowledge gained and formulate a path toward patient-specific cGvHD therapy.

Intestinal permeability in patients undergoing stem cell transplantation correlates with systemic acute phase responses and dysbiosis

Intestinal permeability may correlate with adverse outcomes during hematopoietic stem cell transplantation (HSCT), but longitudinal quantification with traditional oral mannitol and lactulose is not feasible in HSCT recipients because of mucositis and diarrhea. A modified lactulose:rhamnose (LR) assay is validated in children with environmental enteritis. Our study objective was to quantify peri-HSCT intestinal permeability changes using the modified LR assay. The LR assay was administered before transplant, at day +7 and +30 to 80 pediatric and young adult patients who received allogeneic HSCT. Lactulose and rhamnose were detected using urine mass spectrometry and expressed as an L:R ratio. Metagenomic shotgun sequencing of stool for microbiome analyses and enzyme-linked immunosorbent assay analyses of plasma lipopolysaccharide binding protein (LBP), ST2, REG3α, claudin1, occludin, and intestinal alkaline phosphatase were performed at the same timepoints. L:R ratios were increased at day +7 but returned to baseline at day +30 in most patients (P = .014). Conditioning regimen intensity did not affect the trajectory of L:R (P = .39). Baseline L:R ratios did not vary with diagnosis. L:R correlated with LBP levels (r2 = 0.208; P = .0014). High L:R ratios were associated with lower microbiome diversity (P = .035), loss of anaerobic organisms (P = .020), and higher plasma LBP (P = .0014). No adverse gastrointestinal effects occurred because of LR. Intestinal permeability as measured through L:R ratios after allogeneic HSCT correlates with intestinal dysbiosis and elevated plasma LBP. The LR assay is well-tolerated and may identify transplant recipients who are more likely to experience adverse outcomes.

Incidence, clinical presentation, risk factors, outcomes, and biomarkers in de novo late acute GVHD

Late acute graft-versus-host disease (GVHD) is defined as de novo acute GVHD presenting beyond 100 days after allogeneic hematopoietic cell transplantation (HCT) without manifestations of chronic GVHD. Data are limited regarding its characteristics, clinical course, and risk factors because of underrecognition and changes in classification. We evaluated 3542 consecutive adult recipients of first HCTs at 24 Mount Sinai Acute GVHD International Consortium (MAGIC) centers between January 2014 and August 2021 to better describe the clinical evolution and outcomes of late acute GVHD. The cumulative incidence of classic acute GVHD that required systemic treatment was 35.2%, and an additional 5.7% of patients required treatment for late acute GVHD. At the onset of symptoms, late acute GVHD was more severe than classic acute GVHD based on both clinical and MAGIC algorithm probability biomarker parameters and showed a lower overall response rate on day 28. Both clinical and biomarker grading at the time of treatment stratified the risk of nonrelapse mortality (NRM) in patients with classic and late acute GVHD, respectively, but long-term NRM and overall survival did not differ between patients with classic and late acute GVHD. Advanced age, female-to-male sex mismatch, and the use of reduced intensity conditioning were associated with the development of late acute GVHD, whereas the use of posttransplant cyclophosphamide-based GVHD prevention was protective mainly because of shifts in GVHD timing. Because overall outcomes were comparable, our findings, although not definitive, suggest that similar treatment strategies, including eligibility for clinical trials, based solely on clinical presentation at onset are appropriate.

Pooled allogeneic faecal microbiota MaaT013 for steroid-resistant gastrointestinal acute graft-versus-host disease: a single-arm, multicentre phase 2 trial

Background

Failure of gastrointestinal acute graft-versus-host disease (GI-aGvHD) to respond to steroid therapy is associated with limited further therapeutic options. We aimed to assess the safety and efficacy of the first-in-human use of the pooled allogeneic faecal microbiota, MaaT013, for the treatment of steroid-refractory GI-aGvHD.

Methods

This prospective, international, single-arm, phase 2a study reports clinical outcomes from a 24-patient cohort with grade III-IV, steroid refractory GI-aGvHD treated with the pooled allogeneic faecal microbiota MaaT013. MaaT013 involved pooling faecal matter from 3 to 8 screened donors then transplanting the pooled batches into patients to treat GI-aGVHD. The 24 patients were treated in the HERACLES study (Aug 2018 to Nov 2020) at 26 sites in Europe and an additional 52 patients were treated in a compassionate use/expanded access program (EAP) in France (July 2018 to April 2021). The primary endpoint was GI response at day 28, defined as the proportion of patients with GI-aGvHD who had a complete response (CR) or very good partial response (VGPR). GvHD grading and staging were assessed according to the revised Glucksberg criteria. Adverse events and severe adverse events were monitored for 6 months and 12 months, respectively. The HERACLES study was registered with ClinicalTrials.gov (NCT03359980).

Findings

Compared with single donors, MaaT013 is characterised by higher microbial richness and reduced variability across batches. At day 28 (D28), the GI-overall response rate (ORR) was 38% in the prospective population, including 5 complete responses (CR), 2 very good partial responses (VGPR) and 2 partial responses (PR). In the EAP, the GI-ORR was 58% (17 CR, 9 VGPR and 4 PR). The 12-month overall survival (OS) was 25% in the prospective study and 38% in the EAP. Regarding safety, five infectious complications, including 3 sepsis, could not be excluded from being related to the study procedure in HERACLES. Shotgun sequencing analyses of the identified strains suggest that none were found in MaaT013. In the EAP, 18 pharmacovigilance cases were reported among 52 treated patients, including 11 bacteraemia/sepsis. In HERACLES, we observed in stools from responding patients at D28 a higher microbiota richness and increased levels of beneficial bacteria, in particular butyrate producers, along with increased levels of short-chain fatty acid and bile acids. In contrast, stools from non-responding (NR) patients displayed increased levels of pathogenic pro-inflammatory bacteria along with increased systemic inflammatory parameters.

Interpretation

Overall, MaaT013 was safe in this population of highly immunocompromised patients and was associated with responses in some patients with GI-aGvHD and deserves further investigation.

Funding

MaaT Pharma.

Chronic graft-versus-host disease in pediatric patients: Differences and challenges

Despite the use of high-resolution molecular techniques for tissue typing, chronic graft-versus-host disease (cGVHD) remains a major complication following allogeneic hematopoietic stem cell transplant. cGVHD adversely affects the life-expectancy and quality of life. The latter is particularly important and functionally relevant in pediatric patients who have a longer life-expectancy than adults. Current laboratory evidence suggests that there is not any difference in the pathophysiology of cGVHD between adults and pediatric patients. However, there are some clinical features and complications of the disease that are different in pediatric patients. There are also challenges in the development of new therapeutics for this group of patients. In this review, we will discuss the epidemiology, pathophysiology, clinical features and consequences of the disease, and highlight the differences between pediatric and adult patients. We will examine the current treatment options for pediatric patients with moderate to severe cGVHD and discuss the challenges facing therapeutic development for cGVHD in the pediatric population.

Safety and efficacy of mesenchymal stromal cell therapy for multi-drug-resistant acute and late-acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation

Graft versus host disease (GvHD) remains a significant risk for mortality and morbidity following allogeneic hematopoietic stem cell transplantation (HSCT). A growing literature supports successful applications of mesenchymal stromal cells (MSCs) for the treatment of steroid-refractory acute GvHD (aGvHD). However, there is limited knowledge about the effects of MSC treatment on late-acute GvHD (late aGvHD). In this article, we present our multicenter study on the safety and efficacy of MSC therapy for patients with steroid-refractory late aGvHD in comparison to those with aGvHD. The outcome measures include non-relapse mortality (NRM) and survival probability over a 2-year follow-up. The study includes a total of 76 patients with grades III-IV aGvHD (n = 46) or late aGvHD (n = 30), who had been treated with at least two lines of steroid-containing immunosuppressive therapy. Patients received weekly adipose or umbilical cord-derived MSC infusions at a dose of median 1.55 (ranging from 0.84 to 2.56) × 106/kg in the aGvHD group, and 1.64 (ranging from 0.85 to 2.58) × 106/kg in the late aGvHD group. This was an add-on treatment to ongoing conventional pharmaceutical management. In the aGvHD group, 23 patients received one or two infusions, 20 patients had 3-4, and three had ≥ 5. Likewise, in the late aGvHD group, 20 patients received one or two infusions, nine patients had 3-4, and one had ≥ 5. MSC was safe without acute or late adverse effects in 76 patients receiving over 190 infusions. In aGvHD group, 10.9% of the patients had a complete response (CR), 23.9% had a partial response (PR), and 65.2% had no response (NR). On the other hand, in the late aGvHD group, 23.3% of the patients had CR, 36.7% had PR, and the remaining 40% had NR. These findings were statistically significant (p = 0.031). Also, at the 2-year follow-up, the cumulative incidence of NRM was significantly lower in patients with late aGvHD than in patients with aGvHD at 40% (95% CI, 25-62%) versus 71% (95% CI, 59-86%), respectively (p = 0.032). In addition, the probability of survival at 2 years was significantly higher in patients with late aGvHD than in the aGvHD group at 59% (95% CI, 37-74%) versus 28% (95% CI, 13-40%), respectively (p = 0.002). To our knowledge, our study is the first to compare the safety and efficacy of MSC infusion(s) for the treatment of steroid-resistant late aGVHD and aGVHD. There were no infusion-related adverse effects in either group. The response rate to MSC therapy was significantly higher in the late aGvHD group than in the aGvHD group. In addition, at the 2-year follow-up, the survival and NRM rates were more favorable in patients with late aGVHD than in those with aGVHD. Thus, the results are encouraging and warrant further studies to optimize MSC-based treatment for late aGVHD.

Acute Graft-versus-Host Disease: An Update on New Treatment Options

Acute graft-versus-host disease (GVHD) occurs in approximately 50% of patients and remains a primary driver of non-relapse and transplant-related mortality. The best treatment remains prevention with either in vivo or ex vivo T-cell depletion, with multiple strategies used worldwide based on factors such as institution preference, ability to perform graft manipulation, and ongoing clinical trials. Predicting patients at high risk for developing severe acute GVHD based on clinical and biomarker-based criteria allows for escalation or potential de-escalation of therapy. Modern therapies for treatment of the disease include JAK/STAT pathway inhibitors, which are standard of care in the second-line setting and are being investigated for upfront management of non-severe risk based on biomarkers. Salvage therapies beyond the second-line remain suboptimal. In this review, we will focus on the most clinically used GVHD prevention and treatment strategies, including the accumulating data on JAK inhibitors in both settings.

[Clinical study of 19 cases of steroid-refractory gastrointestinal acute graft-versus-host disease after allogeneic hematopoietic stem cell transplantation with fecal microbiota transplantation]

Objective: To investigate the clinical efficacy of fecal microbiota transplantation (FMT) for treating steroid-refractory gastrointestinal acute graft-versus-host disease (GI-aGVHD) . Methods: This analysis included 29 patients with hematology who developed steroid-refractory GI-aGVHD after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Huaian Hospital Affiliated to Xuzhou Medical University from March 2017 to March 2022. Among them, 19 patients underwent FMT treatment (the FMT group) and 10 patients did not (the control group). The efficacy and safety of FMT were assessed, as well as the changes in intestinal microbiota abundance, lymphocyte subpopulation ratio, peripheral blood inflammatory cytokines, and GVHD biomarkers before and after FMT treatment. Results: ① Complete remission of clinical symptoms after FMT was achieved by 13 (68.4%) patients and 2 (20.0%) controls, with a statistically significant difference (P<0.05). Intestinal microbiota diversity increased and gradually recovered to normal levels after FMT and FMT-related infections did not occur. ②The proportion of CD3(+) and CD8(+) cells in the FMT group after treatment decreased compared with the control group, and the ratio of CD4(+), regulatory T cells (Treg), and CD4(+)/CD8(+) cells increased (all P< 0.05). The interleukin (IL) -6 concentration in the FMT group was lower than that in the control group [4.15 (1.91-5.71) ng/L vs 6.82 (2.40-8.91) ng/L, P=0.040], and the IL-10 concentration in the FMT group was higher than that in the control group [12.11 (5.69-20.36) ng/L vs 7.51 (4.10-9.58) ng/L, P=0.024]. Islet-derived protein 3α (REG3α) was significantly increased in patients with GI-aGVHD, and the REG3α level in the FMT group was lower than that in the control group after treatment [30.70 (10.50-105.00) μg/L vs 74.35 (33.50-139.50) μg/L, P=0.021]. Conclusion: FMT is a safe and effective method for the treatment of steroid-refractory GI-aGVHD by restoring intestinal microbiota diversity, regulating inflammatory cytokines, and upregulating Treg cells.

A Pilot Trial of Patient-Reported Outcomes for Acute Graft-Versus-Host-Disease

BACKGROUND

Acute graft-versus-host disease (GVHD) is a major cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (HCT). Acute GVHD is associated with severe physical and psychosocial symptoms.

OBJECTIVES

We sought to evaluate the feasibility of capturing patient-reported outcome (PRO) measures in acute GVHD to better measure symptom burden and quality of life (QOL).

STUDY DESIGN

We conducted a pilot study of adult patients undergoing first allogeneic HCT. Questions from FACT-BMT, PROMIS-10, and PRO-CTCAE were selected, and the survey was administered electronically pre-HCT, at days 14, 50, and 100 post-HCT. In addition, patients who developed grade 2-4 acute GVHD received it weekly for four weeks and then monthly up to 3 months.

RESULTS

From 2018 to 2020, 73 patients were consented, of which 66 went on to receive HCT and were included in the analysis. Median age at transplant was 63 years, and 92% were Caucasian. Only 47% of expected surveys were completed (range 0-67% for each time point). Descriptive exploratory analysis demonstrate an expected trajectory of QOL using the FACT-BMT and PROMIS-10 scores throughout transplant. Patients who developed acute GVHD (N=15) generally had lower QOL scores compared to those with no or mild GVHD post-HCT. The PRO-CTCAE captured several physical and mental/emotional symptoms in all patients and those with GVHD. Fatigue (100%), decreased appetite (92%), problem tasting (85%), loose stools (77%), pain (77%), skin itching (77%) and depression (feeling sad) (69%) were the most prevalent symptoms among patients with grade 2-4 acute GVHD. Patients with acute GVHD generally reported worse symptoms than those with no/mild GVHD in frequency, severity, and interference in normal activities. Several challenges were identified including poor access/literacy of electronic surveys, acute illness, and need for extensive research/resource support.

CONCLUSIONS

We demonstrate the challenges yet potential of using PRO measures in acute GVHD. We demonstrate that the PROMIS-10 and PRO-CTCAE measures are able to capture several symptoms and QOL domains of acute GVHD. Further investigation into making PROs feasible in acute GVHD are needed.

Inflammatory CD4/CD8 double-positive human T cells arise from reactive CD8 T cells and are sufficient to mediate GVHD pathology

An important paradigm in allogeneic hematopoietic cell transplantations (allo-HCTs) is the prevention of graft-versus-host disease (GVHD) while preserving the graft-versus-leukemia (GVL) activity of donor T cells. From an observational clinical study of adult allo-HCT recipients, we identified a CD4+/CD8+ double-positive T cell (DPT) population, not present in starting grafts, whose presence was predictive of ≥ grade 2 GVHD. Using an established xenogeneic transplant model, we reveal that the DPT population develops from antigen-stimulated CD8 T cells, which become transcriptionally, metabolically, and phenotypically distinct from single-positive CD4 and CD8 T cells. Isolated DPTs were sufficient to mediate xeno-GVHD pathology when retransplanted into naïve mice but provided no survival benefit when mice were challenged with a human B-ALL cell line. Overall, this study reveals human DPTs as a T cell population directly involved with GVHD pathology.

Harmonizing Definitions for Diagnostic Criteria and Prognostic Assessment of Transplantation-Associated Thrombotic Microangiopathy: A Report on Behalf of the European Society for Blood and Marrow Transplantation, American Society for Transplantation and Cellular Therapy, Asia-Pacific Blood and Marrow Transplantation Group, and Center for International Blood and Marrow Transplant Research

Transplantation-associated thrombotic microangiopathy (TA-TMA) is an increasingly recognized complication of hematopoietic cell transplantation (HCT) associated with significant morbidity and mortality. However, TA-TMA is a clinical diagnosis, and multiple criteria have been proposed without universal application. Although some patients have a self-resolving disease, others progress to multiorgan failure and/or death. Poor prognostic features also are not uniformly accepted. The lack of harmonization of diagnostic and prognostic markers has precluded multi-institutional studies to better understand incidence and outcomes. Even current interventional trials use different criteria, making it challenging to interpret the data. To address this urgent need, the American Society for Transplantation and Cellular Therapy, Center for International Bone Marrow Transplant Research, Asia-Pacific Blood and Marrow Transplantation, and European Society for Blood and Marrow Transplantation nominated representatives for an expert panel tasked with reaching consensus on diagnostic and prognostic criteria. The panel reviewed literature, generated consensus statements regarding diagnostic and prognostic features of TA-TMA using the Delphi method, and identified future directions of investigation. Consensus was reached on 4 key concepts: (1) TA-TMA can be diagnosed using clinical and laboratory criteria or tissue biopsy of kidney or gastrointestinal tissue; however, biopsy is not required; (2) consensus diagnostic criteria are proposed using the modified Jodele criteria with additional definitions of anemia and thrombocytopenia. TA-TMA is diagnosed when ≥4 of the following 7 features occur twice within 14 days: anemia, defined as failure to achieve transfusion independence despite neutrophil engraftment; hemoglobin decline by ≥1 g/dL or new-onset transfusion dependence; thrombocytopenia, defined as failure to achieve platelet engraftment, higher-than-expected transfusion needs, refractory to platelet transfusions, or ≥50% reduction in baseline platelet count after full platelet engraftment; lactate dehydrogenase (LDH) exceeding the upper limit of normal (ULN); schistocytes; hypertension; soluble C5b-9 (sC5b-9) exceeding the ULN; and proteinuria (≥1 mg/mg random urine protein-to-creatinine ratio [rUPCR]); (3) patients with any of the following features are at increased risk of nonrelapse mortality and should be stratified as high-risk TA-TMA: elevated sC5b-9, LDH ≥2 times the ULN, rUPCR ≥1 mg/mg, multiorgan dysfunction, concurrent grade II-IV acute graft-versus-host disease (GVHD), or infection (bacterial or viral); and (4) all allogeneic and pediatric autologous HCT recipients with neuroblastoma should be screened weekly for TA-TMA during the first 100 days post-HCT. Patients diagnosed with TA-TMA should be risk-stratified, and those with high-risk disease should be offered participation in a clinical trial for TA-TMA-directed therapy if available. We propose that these criteria and risk stratification features be used in data registries, prospective studies, and clinical practice across international settings. This harmonization will facilitate the investigation of TA-TMA across populations diverse in race, ethnicity, age, disease indications, and transplantation characteristics. As these criteria are widely used, we expect continued refinement as necessary. Efforts to identify more specific diagnostic and prognostic biomarkers are a top priority of the field. Finally, an investigation of the impact of TA-TMA-directed treatment, particularly in the setting of concurrent highly morbid complications, such as steroid-refractory GVHD and infection, is critically needed.

EASIX predicts non-relapse mortality after haploidentical transplantation with post-transplant cyclophosphamide

Endothelial Activation and Stress Index (EASIX) is a prognostic score reflecting endothelial damage. It can identify cohorts of patients at higher risk of non-relapse mortality (NRM) after allogeneic stem cell transplantation (SCT) from a matched-related or -unrelated donor. No data are available in the setting of haploidentical-SCT with post-transplant cyclophosphamide (PT-Cy). We retrospectively analyzed the role of EASIX score in a cohort of 266 patients receiving Haplo-SCT with PT-Cy at our center. By a decision-tree model, 1-year NRM was 16% vs. 29% and overall survival was 59% vs. 32%, respectively, for patients with a pre-transplant EASIX (EASIX-PRE) <0.8 vs. ≥0.8 (p < 0.001). By multivariable analysis, EASIX-PRE was an independent predictor of NRM (hazard ratio [HR] 2.43, p < 0.001) and overall survival (HR: 1.64, p = 0.011). EASIX-PRE did not predict patients at higher risk of developing acute graft-versus-host disease (GVHD) but was an independent predictor of 1-year NRM (3.2 cutoff, HR 6.61, p = 0.002; <3.2 vs. ≥3.2: 10% vs. 56%, p < 0.001) in patients developing acute GVHD. EASIX score can also represent an important tool to predict mortality in the setting of Haplo-SCT with PT-Cy. It may help to make therapeutic decisions both before the transplant and at the onset of acute GVHD.