Treatment-Responsive Acute Graft-versus-Host Disease after Post-Transplantation Cyclophosphamide-Based Prophylaxis: Incidence and Clinical Outcomes.

Post-transplantation cyclophosphamide (PTCy) following hematopoietic cell transplantation (HCT) has emerged as standard of care for graft-versus-host disease (GVHD) prevention in adult patients without increasing malignant relapse. We previously defined acute GVHD (aGVHD) treatment response categories as corticosteroid-sensitive (SS), -dependent (SD), or -resistant (SR) based on response to first-line corticosteroids and reported their clinical outcomes following non-PTCy-based prophylaxis. More than one-third of patients developed aGVHD necessitating systemic therapy. Cases were predominantly SR, with a 14% overall incidence of SR aGVHD. The incidence and clinical outcomes of these 3 distinct aGVHD treatment response groups following PTCy-based prophylaxis have not been well described. The objective of this retrospective single-institution cohort study was to assess the incidence and clinical outcomes of SS, SD, and SR aGVHD following HCT with PTCy-based prophylaxis using a prophylactic regimen of PTCy, tacrolimus, and mycophenolate mofetil (MMF). We included 196 consecutive adult and pediatric patients undergoing allogeneic HCT for malignant and non-malignant disorders at the University of Minnesota between 2017 and 2021. Patients received PTCy on days +3 and +4 plus tacrolimus and MMF prophylaxis. Bone marrow and peripheral blood stem cell graft sources and related and unrelated donors were included. Recipients received myeloablative or reduced-intensity conditioning regimens. Of the 196 allografts, 54 (28%) developed aGVHD before day +180, with a median time to onset of 50 days (interquartile range, 34 to 71 days). Of those, 32 patients (16% overall) developed maximum grade II-III aGVHD necessitating systemic corticosteroids, with the following response: 13 SS (41%), 10 SD (31%), and 9 SR (28%). The overall incidence of SR aGVHD was 4.6%. Only 12 patients (6%) developed maximum grade III aGVHD, and none had grade IV aGVHD. The 2-year overall survival analyzed from 80 days after initiation of systemic treatment was similar in the SS and SD groups (77 and 75%, respectively), comparable to those without aGVHD (81%), and was lowest in the SR group (20%), with GVHD the primary cause of death. Nonrelapse mortality was highest in the SR group. MN high-risk and higher GVHD grade at onset were risk factors for developing SR aGVHD. Overall, we report a low incidence (16%) of aGVHD requiring systemic corticosteroids with PTCy-based prophylaxis. aGVHD cases were predominantly SS aGVHD, with lower incidences of SD and SR aGVHD. Our findings suggest that PTCy-based prophylaxis reduces the rate of treatment-resistant aGVHD. Patients with SR aGVHD had the worst clinical outcomes and poorest survival. Those with SS and SD aGVHD had similar clinical outcomes, both better than seen with SR aGVHD.

Outcomes of human leukocyte antigen-matched related donor and haploidentical allogeneic hematopoietic cell transplantation recipients by immune profiles of recipients and donors.

BACKGROUND: Haploidentical (Haplo) allogeneic HCTs (alloHCT) have been used more frequently over the last decade as survival is similar to HLA-matched related donor (MRD) alloHCTs. OBJECTIVE: We aimed to identify donor and recipient immune signatures before alloHCT that are associated with clinically meaningful outcomes in MRD vs Haplo alloHCT recipients. STUDY DESIGN: This retrospective cohort study of 165 MRD (n=132) and Haplo (n=33) alloHCT recipients and their related donors between 2007-2019 with paired peripheral blood samples immunophenotyped for T-cell, B-cell, NK cell and dendritic cell (DC) subsets. Immune cells were quantified before alloHCT in donors and recipients; calculations of immune cell ratios were classified as high, intermediate, and low and analyzed with alloHCT outcomes. RESULTS: Haplo donors were younger than MRD donors (median: 35 vs 51 years), whereas Haplo recipients were older than MRD recipients (median: 68 vs 54 years), were more likely to have a Karnofsky Performance Score ≤70 (76% vs 57%), 3+ comorbidities (54% vs 47%), and were in complete remission prior to alloHCT (58% vs 42%). In MRD alloHCT, a lower ratio of CD4+ to CD8+ effector memory cells in the donor was associated with lower 4-yr overall survival (OS; 25% v 61%; p=0.009), lower 4-yr progression free survival (PFS; 25% v 58%; p=0.014) and higher incidence of 1-yr transplant-related mortality (TRM; 39% v 7%; p=0.009) in recipients. A higher ratio of CD8+ effector memory to total NK cells measured in MRD recipients was associated with a higher incidence of grade II-IV aGvHD (63% v 37%; p=0.004) but was not statistically significant for III-IV aGvHD (23% v 12%). In Haplo alloHCT, a lower ratio of total T-regulatory to CD4+ central memory cells in the donor was associated with lower 4-yr PFS (22% v 60%; p=0.0091). A higher ratio of CD4+ effector memory to CD8+ effector memory cells measured in Haplo recipients pre-alloHCT was associated with lower 4-yr OS (25% v 88%; p=0.0039). In both MRD and Haplo recipients, a higher ratio of CD4+ naïve to CD4+ central memory cells was associated with a higher incidence of grade II-IV aGvHD (64% v 38%; p=0.04). CONCLUSION: Evaluation of pre-alloHCT immune signatures of the donor and recipient may influence clinically meaningful patient outcomes in both MRD and Haplo transplants.

Multi-omics analysis of a fecal microbiota transplantation trial identifies novel aspects of acute graft-versus-host disease pathogenesis.

Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic hematopoietic cell transplantation (alloHCT) associated with gut microbiota disruptions. However, whether therapeutic microbiota modulation prevents aGVHD is unknown. We conducted a randomized, placebo-controlled trial of third-party fecal microbiota transplantation (FMT) administered at the peak of microbiota injury in 100 patients with acute myeloid leukemia receiving induction chemotherapy and alloHCT recipients. Despite improvements in microbiome diversity, expansion of commensals, and shrinkage of potential pathogens, aGVHD occurred more frequently after FMT than placebo. Although this unexpected finding could be explained by clinical differences between the two arms, we asked whether a microbiota explanation might be also present. To this end, we performed multi-omics analysis of pre- and post-intervention gut microbiome and serum metabolome. We found that post-intervention expansion of Faecalibacterium, a commensal genus with gut-protective and anti-inflammatory properties under homeostatic conditions, predicted a higher risk for aGVHD. Faecalibacterium expansion occurred predominantly after FMT and was due to engraftment of unique donor taxa, suggesting that donor Faecalibacterium-derived antigens might have stimulated allogeneic immune cells. Faecalibacterium and ursodeoxycholic acid (an anti-inflammatory secondary bile acid) were negatively correlated, offering an alternative mechanistic explanation. In conclusion, we demonstrate context dependence of microbiota effects where a normally beneficial bacteria may become detrimental in disease. While FMT is a broad, community-level intervention, it may need precision engineering in ecologically complex settings where multiple perturbations (e.g. antibiotics, intestinal damage, alloimmunity) are concurrently in effect.

Amphiregulin, ST2,and REG3α Biomarker Risk Algorithms as Predictors of Non-Relapse Mortality in Patients with Acute GVHD.

Graft-vs-host disease (GVHD) is a major cause of non-relapse mortality (NRM) following allogeneic hematopoietic cell transplant (HCT). Algorithms containing either the GI GVHD biomarker amphiregulin (AREG) or a combination of two GI GVHD biomarkers, (ST2+REG3α) when measured at GVHD diagnosis are validated predictors of NRM risk, but have never been assessed in the same patients using identical statistical methods. We measured serum concentrations of ST2, REG3, and AREG by ELISA at the time of GVHD diagnosis in 715 patients divided by date of transplant into training (2004-2015) and validation (2015-2017) cohorts. The training cohort (n=341) was used to develop algorithms for predicting probability of 12 month NRM that contained all possible combinations of 1-3 biomarkers and a threshold corresponding to the concordance probability was used to stratify patients for risk of NRM. Algorithms were compared to each other based on several metrics including the area under the receiver operating characteristics curve (AUC), proportion of patients correctly classified, sensitivity, and specificity using only the validation cohort (n=374). All algorithms were strong discriminators of 12 month NRM, whether or not patients were systemically treated (n=321). An algorithm containing only ST2+REG3α had the highest AUC (0.757), correctly classified the most patients (75%), and more accurately risk stratified those who developed Minnesota standard risk GVHD and for patients who received post-transplant cyclophosphamide-based prophylaxis. An algorithm containing only AREG more accurately risk stratified patients with Minnesota high risk GVHD. Combining ST2, REG3α, and AREG into a single algorithm did not improve performance.

Long- and short-term effects of fecal microbiota transplantation on antibiotic resistance genes: results from a randomized placebo-controlled trial.

In small series, third-party fecal microbiota transplantation (FMT) has been successful in decolonizing the gut from clinically relevant antibiotic resistance genes (ARGs). Less is known about the short- and long-term effects of FMT on larger panels of ARGs. We analyzed 226 pre- and post-treatment stool samples from a randomized placebo-controlled trial of FMT in 100 patients undergoing allogeneic hematopoietic cell transplantation or receiving anti-leukemia induction chemotherapy for 47 ARGs. These patients have heavy antibiotic exposure and a high incidence of colonization with multidrug-resistant organisms. Samples from each patient spanned a period of up to 9 months, allowing us to describe both short- and long-term effects of FMT on ARGs, while the randomized design allowed us to distinguish between spontaneous changes vs. FMT effect. We find an overall bimodal pattern. In the first phase (days to weeks after FMT), low-level transfer of ARGs largely associated with commensal healthy donor microbiota occurs. This phase is followed by long-term resistance to new ARGs as stable communities with colonization resistance are formed after FMT. The clinical implications of these findings are likely context-dependent and require further research. In the setting of cancer and intensive therapy, long-term ARG decolonization could translate into fewer downstream infections.

Treatment-Sensitive and Treatment-Dependent Chronic Graft-versus-Host Disease Yield Superior Failure-Free and Overall Survival Compared to Treatment-Resistant Chronic Graft-versus-Host Disease.

Response to treatment of chronic graft-versus-host disease (cGVHD) may help predict prognosis and outcomes. We hypothesized that the response of cGVHD to treatment and the ability to taper immunosuppression define distinct treatment response categories that differ in terms of risk factors and prognosis. Our aim was to determine specific clinical characteristics and outcomes associated with 3 distinct cGVHD treatment response groups based on the response to and duration of immunosuppressive therapy (IST) as treatment-sensitive (TS), treatment-resistant (TR), and treatment-dependent (TD) cGVHD. This retrospective single-institution cohort study included 1142 consecutive adult and pediatric recipients of allogeneic hematopoietic cell transplantation (HCT) performed for malignant and nonmalignant disorders at the University of Minnesota between 2008 and 2016. All donor, graft, conditioning regimen, and GVHD prophylaxis strategies were included, but only patients who commenced systemic treatment within 30 days of cGVHD diagnosis were included. A total of 185 patients who developed cGVHD necessitating IST within 30 days of cGVHD diagnosis were included in this analysis. At 1 year after cGVHD onset, 13% of the patients were TS, 27% were TD, and 60% were TR (including 14% deceased), whereas at 2 years after cGVHD onset, 29% were TS, 5% were TD, and 66% were TR (including 22% deceased). In a landmark analysis starting at 1 year after cGVHD onset, 5-year failure-free survival (FFS) and overall survival (OS) were lowest in the TR group (FFS, 38%; OS, 70%), with comparable outcomes in the TD (74% and 82%, respectively) and TS (79% for both) groups. Compared to no cGVHD, TR cGVHD was associated with worse OS at 5 years after cGVHD (hazard ratio, 2.09 versus no cGVHD; 95% confidence interval, 1.3 to 3.3; P < .01). Our findings suggest that refining cGVHD classification into 3 treatment response states defines important predictors of early and late clinical outcomes and identifies patients needing more effective treatment.

The development and flux of the University of Minnesota Survivorship Program: progress, challenges, and opportunities.

For the past 30 years, the University of Minnesota's Cancer Survivorship Program has been dedicated to providing exceptional care to patients who have lived the cancer experience. Our model is consultative, risk-stratified, and oncologist-led but executed predominately by advanced practice providers. Care is personalized and serves three survivor populations: children, adults, and patients who received BMT with over 500 new patients evaluated annually. As guidelines and survivorship standards have changed, our clinical programs have evolved from a focus on survivorship care plans to supportive care. The program offers a wide range of supportive services from acupuncture to nutritional services as well as several educational programs for patients. The program has a strong research legacy, notably as the birthplace of research that led to the Children's Oncology Group Guidelines as well as advancements in cardio-oncology and frailty after bone marrow transplantation. In 2021, we hosted the first annual Survivorship Research Forum, providing the opportunity and space for experts across disciplines to exchange ideas on a broad range of survivorship topics not possible at other national cancer-related conferences. With successes and challenges, we have identified opportunities for growth as our program continues to evolve and grow in our goal to improve cancer outcomes along a wide spectrum of physical, emotional, functional, and social dimensions. IMPLICATIONS FOR CANCER SURVIVORS: The University of Minnesota Cancer Survivorship Program provides care, education, and research opportunities for patients across the cancer continuum.

The best GVHD prophylaxis: Or at least progress towards finding it.

Options for GVHD prophylaxis after allogeneic hematopoietic cell transplantation can best be chosen by understanding the pathophysiology of GVHD. Interventions to limit T cell activation, expansion and subsequent tissue injury can each be utilized in designing successful GVHD prevention strategies Depleting, tolerizing or blunting T cells or host antigen presenting cells (APCs), blocking co-stimulation or more broadly suppressing inflammation have all been used. Interventions which spare regulatory T cells (Tregs) may prevent GVHD and facilitate controlled allo-responses and not compromise subsequent relapse risks. Graft manipulations and pharmacologic interventions each have potential to limit the morbidity of GVHD while permitting the immunocompetence to prevent infection or relapse.

Potential of Fecal Microbiota Transplantation to Prevent Acute GVHD: Analysis from a Phase II Trial.

PURPOSE: Intestinal microbiota disruptions early after allogeneic hematopoietic cell transplantation have been associated with increased risk for acute GVHD (aGVHD). In our recent randomized phase II trial of oral, encapsulated, third-party fecal microbiota transplantation (FMT) versus placebo, FMT at the time of neutrophil recovery was safe and ameliorated dysbiosis. Here, we evaluated in post hoc analysis whether donor microbiota engraftment after FMT may protect against aGVHD. EXPERIMENTAL DESIGN: We analyzed pre- and post-FMT stool samples and estimated donor microbiota engraftment (a preplanned secondary endpoint) by determining the fraction of post-FMT microbiota formed by unique donor taxa (donor microbiota fraction; dMf). RESULTS: dMf was higher in patients who later developed grade I or no aGVHD (median 33.9%; range, 1.6%-74.3%) than those who developed grade II-IV aGVHD (median 25.3%; range, 2.2%-34.8%; P = 0.006). The cumulative incidence of grade II-IV aGVHD by day 180 was lower in the group with greater-than-median dMf than the group with less-than-median dMf [14.3% (95% confidence interval, CI, 2.1-37.5) vs. 76.9% (95% CI, 39.7-92.8), P = 0.008]. The only determinant of dMf in cross-validated least absolute shrinkage and selection operator (LASSO)-regularized regression was the patient's pre-FMT microbiota diversity (Pearson correlation coefficient -0.82, P = 1.6 × 10-9), indicating more potent microbiota modulation by FMT in patients with more severe dysbiosis. Microbiota network analysis revealed major rewiring including changes in the most central nodes, without emergence of keystone species, as a potential mechanism of FMT effect. CONCLUSIONS: FMT may have protective effects against aGVHD, especially in patients with more severe microbiota disruptions.

Temporal variation in oral microbiome composition of patients undergoing autologous hematopoietic cell transplantation with keratinocyte growth factor.

INTRODUCTION: Autologous hematopoietic cell transplantation (AHCT) is a well-established treatment for lymphoma. Unintended effects of this therapy include oral mucositis (OM) and gastrointestinal toxicities, resulting in poor clinical outcomes. The gut microbiome has been previously linked to transplant toxicities among allogeneic recipients, but little is known about the effects of AHCT on the oral microbiome. METHODS: Seven patients with non-Hodgkin or Hodgkin lymphoma undergoing AHCT with palifermin (keratinocyte growth factor) were included. Buccal swab samples were collected at baseline and 14- and 28-days post-treatment. Oral microbial communities were characterized with 16 S rRNA amplicon sequencing. Temporal trends in community composition, alpha diversity, and beta diversity were investigated. RESULTS: A significant reduction in the relative abundance of the genera Gemella and Actinomyces were observed from baseline. No significant temporal differences in alpha diversity were observed. Significant changes in beta diversity were recorded. CONCLUSION: Results of this pilot study suggest treatment with AHCT and palifermin affects the oral microbiome, resulting in temporal shifts in oral microbial community composition. Future studies are warranted to confirm these trends and further investigate the effects of AHCT on the oral microbiome and how these shifts may affect health outcomes.

Amphiregulin as monitoring biomarker for life-threatening acute graft-versushost disease: secondary analysis of two prospective clinical trials.

Not available.

Graft-versus-host disease: teaching old drugs new tricks at less cost.

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic stem cell transplantation (SCT). Currently, more patients can receive SCT. This is attributed to the use of reduced intensity regimens and the use of different GVHD prophylaxis that breaks the barrier of human leukocyte antigen, allowing an increase in the donor pool. Once an area with relatively few clinical trial options, there has been an increase in interest in GVHD prophylaxis and treatment, which has led to many US Food and Drug Administration (FDA) approvals. Although there is considerable excitement over novel therapies, many patients may not have access to them due to geographical or other resource constraints. In this review article, we summarize the latest evidence on how we can continue to repurpose drugs for GVHD prophylaxis and treatment. Drugs covered by our review include those that have been FDA approved for other uses for at least 15 years (since 2008); thus, they are likely to have generic equivalents available now or in the near future.

Pre-transplant and longitudinal changes in faecal microbiome characteristics are associated with subsequent development of chronic graft-versus-host disease.

The role of the gastrointestinal microbiome in predisposing to chronic graft-versus-host disease (cGVHD), an immune-mediated haematopoietic cell transplant (HCT) complication, is not well defined. We examined the relationship of the host faecal microbiome with subsequent cGVHD development by analysing baseline stool samples as well as post-HCT changes in microbiome composition and metabolite pathway analyses. We analysed pre-transplant baseline samples from 11 patients who subsequently developed cGVHD compared to 13 controls who did not develop acute GVHD or cGVHD at any time. We found a significant differential abundance of multiple taxa at baseline between cGVHD versus controls, including the Actinobacteria phylum and Clostridium genus. A subgroup analysis of longitudinal samples within each patient revealed a greater loss of alpha diversity from baseline to post-engraftment in patients who subsequently developed cGVHD. Metabolic pathways analysis revealed that two pathways associated with short-chain fatty acid metabolism were enriched in cGVHD patient microbiomes: ß-oxidation and acyl-CoA synthesis, and γ-aminobutyrate shunt. In contrast, a tryptophan catabolism pathway was enriched in controls. Our findings show a distinct pattern of baseline microbiome and metabolic capacity that may play a role in modulating alloreactivity in patients developing cGVHD. These findings support the therapeutic potential of microbiome manipulation for cGVHD prevention.

Phase II, Open-Label Clinical Trial of Urinary-Derived Human Chorionic Gonadotropin/Epidermal Growth Factor for Life-Threatening Acute Graft-versus-Host Disease.

Treatments that aid inflammation resolution, immune tolerance, and epithelial repair may improve outcomes beyond high-dose corticosteroids and other broad immunosuppressants for life-threatening acute graft-versus-host disease (aGVHD). We studied the addition of urinary-derived human chorionic gonadotropin/epidermal growth factor (uhCG/EGF; Pregnyl; Organon, Jersey City, NJ) to standard aGVHD therapy in a prospective Phase II clinical trial (ClinicalTrials.gov identifier NCT02525029). Twenty-two patients with Minnesota (MN) high-risk aGVHD received methylprednisolone 48 mg/m2/day plus 2000 units/m2 of uhCG/EGF s.c. every other day for 1 week. Patients requiring second-line aGVHD therapy received uhCG/EGF 2000 to 5000 units/m2 s.c. every other day for 2 weeks plus standard of care immunosuppression (physician's choice). Responding patients were eligible to receive maintenance doses twice weekly for 5 weeks. Immune cell subsets in peripheral blood were evaluated by mass cytometry and correlated with plasma amphiregulin (AREG) level and response to therapy. Most patients had stage 3-4 lower gastrointestinal tract GVHD (52%) and overall grade III-IV aGVHD (75%) at time of enrollment. The overall proportion of patients with a response at day 28 (primary endpoint) was 68% (57% with complete response, 11% with partial response). Nonresponders had higher baseline counts of KLRG1+ CD8 cells and T cell subsets expressing TIM-3. Plasma AREG levels remained persistently elevated in nonresponders and correlated with AREG expression on peripheral blood T cells and plasmablasts. The addition of uhCG/EGF to standard therapy is a feasible supportive care measure for patients with life-threatening aGVHD. As a commercially available, safe, and inexpensive drug, uhCG/EGF added to standard therapy may reduce morbidity and mortality from severe aGVHD and merits further study.

Phase II Study of Myeloablative 7-8/8-Matched Allotransplantation with Post-Transplantation Cyclophosphamide, Tacrolimus, and Mycophenolate Mofetil.

Graft-versus-host disease (GVHD) is the major toxicity of allogeneic hematopoietic cell transplantation (HCT). We hypothesized that a GVHD prophylaxis regimen of post-transplantation cyclophosphamide (PTCy), tacrolimus (Tac), and mycophenolate mofetil (MMF) would be associated with incidences of acute and chronic GVHD in patients receiving a matched or single antigen mismatched HCT. This Phase II study was conducted at the University of Minnesota using a myeloablative regimen of either total body irradiation (TBI) at a total dose of 1320 cGy, administered in 165-cGy fractions, twice daily from day -4 to day -1, or busulfan (Bu) 3.2 mg/kg daily (cumulative area under the curve, 19,000 to 21,000 µmol/min/L) plus fludarabine (Flu) 40 mg/m2 once daily on days -5 to -2, followed by a GVHD prophylaxis regimen of PTCy 50 mg/kg on days +3 and +4, Tac, and MMF beginning on day +5. The primary endpoint was the cumulative incidence of chronic GVHD necessitating systemic immunosuppression (IST) at 1 year post-transplantation. Between March 2018 and May 2022, we enrolled 125 pediatric and adult patients, with a median follow-up of 813 days. The incidence of chronic GVHD necessitating systemic IST at 1 year was 5.5%. The rate of grade II-IV acute GVHD was 17.1%, and that of grade III-IV acute GVHD was 5.5%. Two-year overall survival was 73.7%, and 2-year graft-versus-host disease-free, relapse-free survival was 52.2%. The 2-year cumulative incidence of nonrelapse mortality was 10.2%, and the rate of relapse was 39.1%. There was no statistically significant difference in survival outcomes between recipients of matched donor transplants versus recipients of 7/8 matched donor transplants. Our data show that myeloablative HCT with PTCy/Tac/MMF results in an extremely low incidence of severe acute and chronic GVHD in well-matched allogeneic HCT.

Post-Transplantation Cyclophosphamide-Based Graft-versus-Host Disease Prophylaxis.

BACKGROUND: In patients undergoing allogeneic hematopoietic stem-cell transplantation (HSCT), a calcineurin inhibitor plus methotrexate has been a standard prophylaxis against graft-versus-host disease (GVHD). A phase 2 study indicated the potential superiority of a post-transplantation regimen of cyclophosphamide, tacrolimus, and mycophenolate mofetil. METHODS: In a phase 3 trial, we randomly assigned adults with hematologic cancers in a 1:1 ratio to receive cyclophosphamide-tacrolimus-mycophenolate mofetil (experimental prophylaxis) or tacrolimus-methotrexate (standard prophylaxis). The patients underwent HSCT from an HLA-matched related donor or a matched or 7/8 mismatched (i.e., mismatched at only one of the HLA-A, HLA-B, HLA-C, and HLA-DRB1 loci) unrelated donor, after reduced-intensity conditioning. The primary end point was GVHD-free, relapse-free survival at 1 year, assessed in a time-to-event analysis, with events defined as grade III or IV acute GVHD, chronic GVHD warranting systemic immunosuppression, disease relapse or progression, and death from any cause. RESULTS: In a multivariate Cox regression analysis, GVHD-free, relapse-free survival was significantly more common among the 214 patients in the experimental-prophylaxis group than among the 217 patients in the standard-prophylaxis group (hazard ratio for grade III or IV acute GVHD, chronic GVHD, disease relapse or progression, or death, 0.64; 95% confidence interval [CI], 0.49 to 0.83; P = 0.001). At 1 year, the adjusted GVHD-free, relapse-free survival was 52.7% (95% CI, 45.8 to 59.2) with experimental prophylaxis and 34.9% (95% CI, 28.6 to 41.3) with standard prophylaxis. Patients in the experimental-prophylaxis group appeared to have less severe acute or chronic GVHD and a higher incidence of immunosuppression-free survival at 1 year. Overall and disease-free survival, relapse, transplantation-related death, and engraftment did not differ substantially between the groups. CONCLUSIONS: Among patients undergoing allogeneic HLA-matched HSCT with reduced-intensity conditioning, GVHD-free, relapse-free survival at 1 year was significantly more common among those who received cyclophosphamide-tacrolimus-mycophenolate mofetil than among those who received tacrolimus-methotrexate. (Funded by the National Heart, Lung, and Blood Institute and others; BMT CTN 1703 ClinicalTrials.gov number, NCT03959241.).

Randomized Double-Blind Phase II Trial of Fecal Microbiota Transplantation Versus Placebo in Allogeneic Hematopoietic Cell Transplantation and AML.

PURPOSE: Gut microbiota injury in allogeneic hematopoietic cell transplantation (HCT) recipients and patients with AML has been associated with adverse clinical outcomes. Previous studies in these patients have shown improvements in various microbiome indices after fecal microbiota transplantation (FMT). However, whether microbiome improvements translate into improved clinical outcomes remains unclear. We examined this question in a randomized, double-blind, placebo-controlled phase II trial. METHODS: Two independent cohorts of allogeneic HCT recipients and patients with AML receiving induction chemotherapy were randomly assigned in a 2:1 ratio to receive standardized oral encapsulated FMT versus placebo upon neutrophil recovery. After each course of antibacterial antibiotics, patients received a study treatment. Up to three treatments were administered within 3 months. The primary end point was 4-month all-cause infection rate. Patients were followed for 9 months. RESULTS: In the HCT cohort (74 patients), 4-month infection density was 0.74 and 0.91 events per 100 patient-days in FMT and placebo arms, respectively (infection rate ratio, 0.83; 95% CI, 0.48 to 1.42; P = .49). In the AML cohort (26 patients), 4-month infection density was 0.93 in the FMT arm and 1.25 in the placebo arm, with an infection rate ratio of 0.74 (95% CI, 0.32 to 1.71; P = .48). Unique donor bacterial sequences comprised 25%-30% of the fecal microbiota after FMT. FMT improved postantibiotic recovery of microbiota diversity, restored several depleted obligate anaerobic commensals, and reduced the abundance of expanded genera Enterococcus, Streptococcus, Veillonella, and Dialister. CONCLUSION: In allogeneic HCT recipients and patients with AML, third-party FMT was safe and ameliorated intestinal dysbiosis, but did not decrease infections. Novel findings from this trial will inform future development of FMT trials.

A prospective phase 2 clinical trial of a C5a complement inhibitor for acute GVHD with lower GI tract involvement.

Involvement of lower gastrointestinal tract (LGI) occurs in 60% of patients with graft-versus-host-disease (GVHD). Complement components C3 and C5 are involved in GVHD pathogenesis. In this phase 2a study, we evaluated the safety and efficacy of ALXN1007, a monoclonal antibody against C5a, in patients with newly diagnosed LGI acute GVHD receiving concomitant corticosteroid. Twenty-five patients were enrolled; one was excluded from the efficacy analysis based upon negative biopsy. Most patients (16/25, 64%) had acute leukemia; 52% (13/25) had an HLA-matched unrelated donor; and 68% (17/25) received myeloablative conditioning. Half the patients (12/24) had a high biomarker profile, Ann Arbor score 3; 42% (10/24) had high-risk GVHD per Minnesota classification. Day-28 overall response was 58% (13/24 complete response, 1/24 partial response), and 63% by Day-56 (all complete responses). Day-28 overall response was 50% (5/10) in Minnesota high-risk and 42% (5/12) in high-risk Ann Arbor patients, increasing to 58% (7/12) by Day-56. Non-relapse mortality at 6-months was 24% (95% CI 11-53). The most common treatment-related adverse event was infection (6/25, 24%). Neither baseline complement levels (except for C5), activity, nor inhibition of C5a with ALXN1007 correlated with GVHD severity or responses. Further studies are needed to evaluate the role of complement inhibition in GVHD treatment.

Phase II Study of Myeloablative 8/8- or 7/8-Matched Allotransplantation with Post-Transplant Cyclophosphamide, Tacrolimus, and Mycophenolate Mofetil: Marked Reduction in GVHD Risk Without Increased Relapse Risk Compared to Historical Cyclosporine/Methotrexate.

Introduction: Graft-versus host disease (GVHD) is a major limitation to the success of allogeneic hematopoietic cell transplant (HCT). We hypothesized that the GVHD prophylaxis regimen of post-transplant cyclophosphamide (PTCy), tacrolimus (Tac) and mycophenolate mofetil (MMF) would reduce the incidence of GVHD in patients receiving a matched or single antigen mismatched HCT without an increase in risk of malignant relapse. Methods: This is a phase II study conducted at the University of Minnesota using a myeloablative regimen of either: (A) total body irradiation (TBI, total dose 1320 cGy, administered in 165 cGy fractions, twice a day from days -4 to -1) or (B) Busulfan 3.2mg/kg daily (cumulative AUC 19,000 - 21,000 µmol/min/L) plus fludarabine 160mg/m2 days -5 to -2, followed by a GVHD prophylaxis regimen of PTCy (50mg/kg days +3 and +4), Tac and MMF (beginning day +5). The primary endpoint is cumulative incidence of chronic GVHD requiring systemic immunosuppression at 1-year post-transplant. We compared results to our previous myeloablative protocol for matched donors utilizing cyclosporine/methotrexate (CSA/MTX) GVHD prophylaxis. Results: From March 2018 - June 2022, we enrolled and treated 125 pediatric and adult patients with a median follow up of 472 days. Grade II-IV acute GVHD occurred in 16% (95% confidence interval (CI): 9-23%); Grade III-IV acute GVHD was 4% (CI: 0-8%). No patients experienced grade IV GVHD, and there were no deaths due to GVHD before day 100. Only 3 developed chronic GVHD requiring immune suppression, (4%, CI: 0-8%). Two-year overall survival (OS) was 80% (CI: 69-87%), and (graft-versus-host disease-free, relapse-free survival) GRFS 57% (CI: 45-67%), both higher than historical CSA/MTX. The incidence of grade II-IV aGVHD, cGVHD, and NRM were all lower with PTCy/Tac/MMF compared to historical CSA/MTX. One-quarter (25%) experienced relapse (CI: 15-36%) similar to historical CSA/MTX. There was no statistically significant difference in survival outcomes between recipients of matched versus 7/8 donors. Conclusion: Myeloablative HCT with PTCy/Tac/MMF results in extremely low incidence of severe acute or chronic GVHD, the primary endpoint of this clinical trial. Relapse risk is not increased compared to our historical CSA/MTX cohort.

Chronic GVHD after steroid-sensitive, -dependent, and -refractory acute GVHD: incidence and clinical outcomes.

Chronic graft-versus-host disease (cGVHD) is a major limitation to the long-term success of allogeneic hematopoietic cell transplantation (HCT). Our prior study of acute GVHD (aGVHD) defined distinct treatment-response groups based on the response to first-line corticosteroids: steroid-sensitive (SS), steroid-resistant (SR), and steroid-dependent (SD) aGVHDs. We conducted a retrospective, single-institution, cohort study to assess the incidence, risk factors, and clinical outcomes of patients with cGVHD after a previous diagnosis of SS, SD, or SR aGVHD, compared with those with no history of aGVHD. Among 784 consecutive adult and pediatric recipients of HCT for hematologic malignancies between 2008 and 2016, 347 (44%) developed aGVHD, with 13% SS, 12% SD, and 19% SR aGVHD. The 3-year cumulative incidence of cGVHD was 25%. Among those with cGVHD, 39% had no prior aGVHD diagnosis, whereas among those with a prior aGVHD diagnosis, 16% had SS, 24% had SD, and 21% had SR aGVHD. Mild or moderate cGVHD was highest among those with preceding SD aGVHD, whereas severe cGVHD was most frequent among those with previous SR aGVHD. We identified SD and SR aGVHDs as significant independent risk factors for the development of cGVHD after allogeneic HCT, whereas SS aGVHD was not a risk factor. Our study demonstrates that cGVHD after SD aGVHD did not have an intermediate prognosis between SR and SS groups as hypothesized; rather, cGVHD after both SD and SR aGVHD have similar prognoses. Our findings suggest that previous aGVHD response states are important predictors of cGVHD severity and outcomes.