Anti-CD19 chimeric antigen receptor T-cell therapy has less efficacy in Richter transformation than in de novo large B-cell lymphoma and transformed low-grade B-cell lymphoma.

The activity of anti-CD19 chimerci antigen receptor (CAR) T-cell therapy in chronic lymphocytic leukemia (CLL) with Richter's transformation (RT) to aggressive large B-cell lymphoma (LBCL) is largely unknown. In a multicenter retrospective study, we report the safety and efficacy of CAR T-cell therapy in patients with RT (N=30) compared to patients with aggressive B-cell lymphoma (N=283) and patients with transformed indolent non-Hodgkin lymphoma (iNHL) (N=141) between April 2016 and January 2023. Two-thirds of patients received prior therapy for CLL before RT and 89% of them received B-cell receptor and B-cell lymphoma 2 inhibitors. Toxicities of CAR T-cell therapy in RT were similar to other lymphomas, with no fatalities related to cytokine release syndrome or immune effector-cell associated neurotoxicity synderome. The 100-day overall response rate and complete response rates in patients with RT were 57% and 47%, respectively. With a median follow-up of 19 months, the median overall survival (OS) was 9.9 months in patients with RT compared to 18 months in de novo LBCL and not reached in patients with transformed iNHL. The OS at 12 months was 45% in patients with RT compared with 62% and 75% in patients with de novo LBCL and transformed iNHL, respectively. In a multivariate analysis, worse OS was associated with RT histology, elevated lactate dehydrogenase, and more prior lines of therapy. CAR T-cell therapy can salvage a proportion of patients with CLL and RT exposed to prior targeted agents; however, efficacy in RT is inferior compared to de novo LBCL and transformed iNHL.

Second hematopoietic stem cell transplantation as salvage therapy for relapsed acute myeloid leukemia/myelodysplastic syndromes after a first transplantation.

Second allogeneic hematopoietic stem-cell transplantation (HSCT2) is a therapeutic option for patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) relapsing after a first transplant (HSCT1). However, patients allocated to HSCT2 may be a selected group with better prognosis and the added efficacy of HSCT2 is not well established. We retrospectively analyzed 407 consecutive patients with relapsed AML/MDS after HSCT1. Sixty-two patients had HSCT2 (15%) and 345 did not. The 2-year cumulative incidence rates of non-relapse mortality and relapse after HSCT2 were 26% (95% confidence interval [95% CI]: 17-39%) and 50% (95% CI: 39-65%), respectively. The 5-year overall survival rates were 25% (95% CI: 14-36%) and 7% (95% CI: 4-10%) in the HSCT2 and no-HSCT2 groups, respectively. Multivariate analysis identified female gender (hazard ratio [HR]=0.31, P=0.001), short remission duration after HSCT1 (HR=2.31, P=0.05), acute graft-versus-host disease after HSCT1 (HR=2.27, P=0.035), HSCT2 from a haplo-identical donor (HR=13.4, P=0.001) or matched unrelated donor (HR=4.53, P=0.007) and relapse after HSCT1 in earlier years (HR=2.46, P=0.02) as factors predicting overall survival after HSCT2. Multivariate analysis of all patients including HSCT2 as a timedependent variable identified relapse within 6 months after HSCT1 (HR=2.32, P<0.001), acute graft-versus-host disease before relapse (HR=1.47, P=0.005), myeloablative conditioning in HSCT1 (HR=0.67, P=0.011), female gender (HR=0.71, P=0.007), relapse in earlier years (HR=1.33, P=0.031) and not having HSCT2 (HR=1.66, P=0.010) as predictive of overall survival after relapse. In conclusion, HSCT2 is associated with longer survival compared to non-transplant treatments and may be the preferred approach in a subset of patients with relapsed AML/MDS after HSCT1.

Immunogenicity and safety of the BNT162b2 mRNA COVID-19 vaccine in haematopoietic stem cell transplantation recipients.

The immunogenicity and safety of Pfizer-BioNTech BNT162b2 mRNA vaccine in allogeneic haematopoietic stem cell transplantation (HSCT) recipients are unknown. We prospectively followed 152 HSCT recipients who were at least six months following transplantation and with no active acute graft-versus-host disease (GVHD). Blood samples were taken 2-4 weeks after the second vaccination and analyzed for receptor-binding domain (RBD) antibodies and neutralizing antibodies (NA). 272 immunocompetent healthcare workers served as controls. At a median of 28 days after the second vaccination, 118 patients (77·6%) developed RBD immunoglobulin G (IgG) with a geometric mean titre (GMT) of 2·61 [95% CI (confidence interval), 2·16-3·16]. In the control group 269/272 (98·9%) developed RBD IgG, with a GMT of 5·98 (95% CI 5·70-6·28), P < 0·0001. The GMT of NA in HSCT recipients and controls was 116·0 (95% CI 76·5-175·9), and 427·9 (95% CI 354·3-516·7) respectively (P < 0001). Multivariate logistic regression analysis revealed that HSCT recipients with no chronic GVHD and no immunosuppressive therapy at the time of vaccination had significantly higher levels of NA following the second vaccination. Adverse events were minimal and were less common than in healthy controls. In conclusion; the BNT162b2 mRNA vaccination is safe and effective in HSCT recipients, especially those who are immunosuppression-free. A significant fraction developed protecting NA.

A phase II study of bisantrene in patients with relapsed/refractory acute myeloid leukemia.

OBJECTIVES: To determine the current role of bisantrene, an anthracene with anthracycline-like activity which was shown in earlier studies to be effective therapy in relapsed/refractory acute myeloid leukemia with no discernible cardiotoxicity, in the treatment of patients with R/R AML. METHODS: This phase 2, single-center study (NCT03820908) enrolled adult R/R AML to receive bisantrene (250 mg/m2 daily for 7 days) which was administered via an intravenous infusion over 2 hours on days 1-7. Disease assessment included routine blood work and bone marrow studies. RESULTS: In all, 10 patients were enrolled with a median of 3 lines of prior therapy including seven patients who had relapsed following allogeneic stem cell transplantation. The most frequently reported grade ≥3 treatment-attributed hematologic AE was thrombocytopenia, whereas the most frequently reported grade ≥3 treatment-attributed non-hematologic AE was mucositis. Of the 10 patients, one (10%) achieved a complete remission and three patients achieved a partial remission resulting in an overall response rate of 40%. Next-generation sequencing of patient samples identified a wide array of mutations associated with activated signaling, splicing, and epigenetic modification. CONCLUSIONS: In view of the observed low toxicity, a follow-up study combining bisantrene with complementary anti-leukemic therapy is planned.

Complete Remission with Incomplete Blood Count Recovery Is a Strong Predictor of Nonrelapse Mortality in Acute Myeloid Leukemia Patients Undergoing Allogeneic Stem Cell Transplantation.

INTRODUCTION: Achievement of an initial complete remission (CR) following induction chemotherapy is tightly correlated with survival in acute myeloid leukemia (AML) patients, yet patients in CR with incomplete hematologic recovery (CRi) still experience improved outcomes compared with nonresponding patients. Whether CRi predicts prognosis in patients referred to an allogeneic stem cell transplantation (allo-SCT) is incompletely defined. In this analysis, we evaluated whether clinical outcomes of transplanted AML patients in CR and CRi were significantly different. METHODS: A retrospective single-center analysis of all de novo AML patients who underwent an allo-SCT between 2001 and 2015. The cohort included all adult patients with AML who underwent a first allo-SCT either in first or second CR or CRi at the time of transplantation. RESULTS: The study cohort included 186 CR patients and 44 CRi patients. In univariate analysis, CRi was associated with inferior 3-year survival and 3-year nonrelapse mortality (NRM) compared to CR (41 vs. 62%; p = 0.022 and 27 vs. 10%; p = 0.006, respectively). In multivariate analysis, CRi was associated with decreased rates of survival (hazard ratio [HR] 2.01; 95% CI, 1.24-3.25; p = 0.005) and NRM (HR, 3.5; 95% CI, 1.6-7.8; p = 0.002). CONCLUSION: CRi in transplanted AML patients is potentially a potent predictor of increased NRM and survival.

Risk factors and implications of oral mucositis in recipients of allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Oral mucositis (OM) is a common toxicity of stem cell transplantation (SCT). We sought to evaluate OM burden, risk factors, and implications in a cohort of allogeneic-SCT recipients. METHODS: This was a single-center study including 115 adult allogeneic-SCT transplanted between 2016 and 2018 for various hematological conditions. Conditioning intensity was categorized as myeloablative (MAC, 39%), reduced intensity (34%), or reduced toxicity (RTC, 27%) in patients conditioned with fludarabine-treosulfan. OM was prospectively graded using the Common Terminology Criteria for Adverse Events (v.4.0) system. RESULTS: Moderate-to-severe OM (grade 2-4) was experienced by 60% of patients. In a univariate analysis, younger age (P = .023), lower body mass index (P = .01), recent smoking (P = .08), recent antibiotics exposure (P = .018), MAC (P < .001), and methotrexate (P = .009) were associated with moderate-to-severe OM. In a multivariable logistic regression model, conditioning and graft-versus-host disease prophylaxis remained significant. OM risk was lowest with RTC (RTC vs MAC: odd ratio [OR] 0.05, P < .001), and recent antibiotic exposure trended toward increased risk (OR 1.88, P = .168). OM was associated with longer hospitalization, delayed neutrophil engraftment, and gastrointestinal-related infections. CONCLUSION: Oral mucositis remains a leading SCT complication. Treosulfan-based conditioning has low mucosal toxicity and is appealing given previous reports on its high efficacy.

A simplified method for detection of N-terminal valine adducts in patients receiving treosulfan.

RATIONALE: Treosulfan is a substance that is being studied as part of the conditioning regimen given prior to allogeneic stem cell transplantation in patients with hematological malignancies. It is known to decompose into 1,2:3,4-diepoxybutane (DEB) under physiologic conditions. In this study, we investigate whether N-terminal valine adducts can be utilized to monitor differences in DEB formation of patients receiving treosulfan as part of the conditioning regimen for transplantation. METHODS: Blood samples were collected from a group of 14 transplant recipients and analyzed for N,N-(2,3-dihydroxy-1,4-butadiyl)valine (pyr-Val) and 2,3,4-trihydroxybutylvaline (THB-Val) adducts as biomarkers for drug uptake and metabolism before treosulfan treatment and 6 days after treatment. RESULTS: A new direct injection liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed and validated prior to clinical analysis. The assay precision was determined by 3 replicate analyses on 3 individual days using control globin spiked with known amounts of pyr-Val and THB-Val. The intra- and inter-day precision coefficients of variance (CVs) and accuracy were < 10% and 15%, respectively. In clinical specimens, the means ± SD of pyr-Val and THB-Val background were 0.29 ± 0.10 pmol/g HB and 5.17 ± 1.7 pmol/g HB, respectively. CONCLUSIONS: These values are similar to those found previously. Treosulfan treatment leads to a significant increase in pyr-Val and THB-Val adducts in each patient (Student's t-test p <0.0001). The mean ± SD amounts of adduct formed were 245.3 ± 89.6 and 210 ± 78.5 pmol/g globin for pyr-Val and THB-Val, respectively. Importantly, these results show that this direct injection method can quantitate both background and treosulfan-induced pyr-Val and THB-Val N-terminal valine globin adducts in humans.

Baseline Renal Function and Albumin are Powerful Predictors for Allogeneic Transplantation-Related Mortality.

Biomarkers measured in blood chemistry before allogeneic hematopoietic stem cell transplantation (HSCT) may reflect patients' physiological status. We hypothesized that selected markers are predictive for nonrelapse mortality (NRM) following transplantation and could contribute to risk assessment. We investigated the value of pre-HSCT albumin, estimated glomerular filtration rate (eGFR), and alkaline phosphatase (AlkP) in predicting NRM. We retrospectively analyzed clinical and laboratory data from 1217 patients receiving a first HSCT in 2 European centers between 2003 and 2015. Transplantation indications and conditioning regimens were diverse. Patients had a median age of 55 years and hematopoietic cell transplantation comorbidity index (HCT-CI) scores of 0 (24%), 1 to 2 (39%), and ≥3 (37%). Cutoffs of eGFR <60 mL/min, albumin <3.5 g/dL, and AlkP >180 IU/L corresponded with 8.8%, 8.3%, and 6.5% of the patients, respectively. eGFR and albumin were associated with increased risk and higher cumulative incidence of day-100, 1-year, and 2-year NRM, both as continuous or categorized variables. A similar pattern was observed for AlkP, except for day-100 NRM. In multivariable analyses, eGFR and albumin were consistently among the top risk factors for early and late-term NRM, abrogating the role of age. Prediction models for day-100, 1-year, and 2-year NRM based only on HCT-CI resulted in c-statistics of .565, .575, and .577, respectively. Addition of both biomarkers increased c-statistics for day-100, 1-year, and 2-year NRM to .651, .633, and .624, respectively. Albumin and eGFR are prognostic biomarkers for NRM after HSCT and improve the discriminative power of the HCT-CI.

Second Malignancies after Hematopoietic Stem Cell Transplantation.

OPINION STATEMENT: Second malignancies are a rare but well-defined late complication after autologous and allogeneic hematopoietic stem-cell transplantation (SCT). Solid malignancies occur in up to 15% of patients 15 years after SCT with myeloablative conditioning, with no plateau in the incidence rates. They are responsible for 5-10% of late deaths after SCT. The incidence is increased with advanced age at SCT. The major risk factors are the use of total body irradiation, which is associated with adenocarcinomas and with chronic graft-versus-host disease which is associated with squamous cell cancers. There is less data on the incidence of second malignancies after reduced-intensity conditioning, but it may not be lower. The types of solid tumors reported in excess include melanoma and other skin cancers; cancers of the oral cavity and head and neck, brain, liver, uterine cervix, thyroid, breast, lung; and possibly gastrointestinal cancers. Therapy-related myeloid neoplasms (t-MN) are more common after autologous SCT and may be related mostly to pre-transplant therapies. Post-transplant lymphoproliferative disease is donor-cell-derived lymphoma that is more common after allogeneic SCT with T-cell depletion or intensive immune-suppression state. Second malignancies are most often treated similarly to the standard therapy for similar malignancies. Lifelong cancer screening and prevention interventions are required for all transplantation survivors.

Isolated Extramedullary Relapse of Acute Leukemia after Allogeneic Stem Cell Transplantation: Different Kinetics and Better Prognosis than Systemic Relapse.

Allogeneic stem cell transplantation (SCT) is curative treatment in patients with acute leukemia and myelodysplastic syndrome. However, recurrent disease is the major cause of treatment failure. Isolated extramedullary relapse (iEMR) after SCT is relatively rare and not well characterized. We performed a retrospective analysis of 566 consecutive patients with acute myeloid leukemia (n = 446) and acute lymphoblastic leukemia (ALL; n = 120) after SCT to study the incidence, risk factors, treatment options, and outcome of iEMR. The 5-year cumulative incidence of bone marrow relapse (BMR) and iEMR was 41.0% and 5.8%, respectively. iEMR occurred significantly later than BMR at 10 and 4 months, respectively (P < .001). Diagnosis of ALL (HR, 2.6; P = .05), poor cytogenetics (HR, 2.1; P = .06), and prior extramedullary disease (HR, 3.8; P = .002) were independent factors predicting iEMR. Acute and chronic graft-versus-host disease (GVHD) reduced the risk of BMR but did not protect against iEMR. Most patients with iEMR received systemic treatment combined with local radiation and donor lymphocyte infusions when feasible. The 3-year survival after relapse was 8.5% and 30.1% after BMR and iEMR, respectively (P = .002). Patients with a first iEMR continued to have recurrent EMRs, and only a minority progressed to BMR. Second iEMR was also common after first BMR and associated with longer survival than second BMR. iEMR is more frequent in patients with ALL and prior extramedullary disease. It occurs later than BMR and more commonly in patients with chronic GVHD, suggesting less effective graft-versus-leukemia effect in extramedullary sites. Second iEMR is common after a first iEMR but also after a first BMR. Long-term survival is feasible with aggressive treatment.

The combination of cyclosporine and mycophenolate mofetil is less effective than cyclosporine and methotrexate in the prevention of acute graft-versus host disease after stem-cell transplantation from unrelated donors.

Acute graft-versus-host disease (GVHD) is the major treatment-related complication after stem-cell transplantation (SCT) from unrelated-donors. Several GVHD prophylaxis regimens have been explored, but no regimen has shown superiority. We analyzed transplantation outcomes in 472 consecutive unrelated-donor SCT recipients, using cyclosporine/methotrexate (MTX, n = 314) or cyclosporine/mycophenolate-mofetil (MMF, n = 158) for GVHD prophylaxis. Neutrophil engraftment was faster after MMF, days 11 and 14, respectively (P = .001). Acute GVHD grade II-IV and III-IV occurred in 47% and 28% after MMF compared to 27% and 12% after MTX, respectively (P < .001). Nonrelapse mortality (NRM) was 44% and 24%, respectively (P < .001). Death associated with GVHD occurred in 25% and 8% (P < .0001), while other NRM causes occurred in 19% and 16%, respectively (P = .39). Relapse mortality was similar. Overall survival was better after MTX, 40% and 29%, respectively (P = .006). However, this difference had only borderline significance when adjusting for differences in patient characteristics (HR, 1.3, P = .08). To minimize potential selection bias we analyzed outcomes on the basis of an intention-to-treat like analysis. During the years 2008-2009, the leading GVHD prophylaxis regimen for unrelated-donor SCT included MMF (89% of transplants). During the other periods, MTX was used predominantly (82% of transplants). The two periods were otherwise well-matched. Acute GVHD occurred more often in 2008-2009. Death associated with GVHD occurred more often, while other NRM causes occurred less often resulting in similar NRM and overall survival. In conclusion, cyclosporine/MMF is associated with faster engraftment and possibly with less organ toxicity than cyclosporine/MTX. However, it is associated with increased rates of acute GVHD and GVHD-associated deaths.

Missing HLA C group 1 ligand in patients with AML and MDS is associated with reduced risk of relapse and better survival after allogeneic stem cell transplantation with fludarabine and treosulfan reduced toxicity conditioning.

Reduced-toxicity conditioning with fludarabine and treosulfan is a dose-intensive regimen with enhanced anti-leukemia effect and acceptable toxicity in AML/MDS. HLA-C regulates natural-killer (NK) cell function by inhibiting Killer immunoglobulin-like receptors (KIR) and is divided into C1 and C2 epitopes. The missing-ligand theory suggests that missing recipient KIR ligands drives NK-alloreactivity after SCT, in the absence of HLA-mismatch by activating unlicensed donor NK cells. We analyzed SCT outcomes in 203 patients with AML/MDS, median age 58 years, given SCT from matched-siblings (n = 97) or matched-unrelated donors (n = 106), using two treosulfan doses (total 36 or 42 g/m2 ). 34% expressed one HLA-C group 1 allele (C1C1), 19% one HLA-C group 2 allele (C2C2), and 48% both KIR ligands (C1C2). Median follow-up was 48 months. 5-year relapse, nonrelapse mortality (NRM) and leukemia-free survival (LFS) rates were 38%, 27%, and 36%, respectively. Relapse rates were 43%, 45%, and 26% in patients expressing C1C1, C1C2, and C2C2 ligands, respectively (P = .03). Multivariate-analysis identified chemo-refractory disease (HR 3.1, P = .003), poor cytogenetics (HR 1.7, P = .08), female donor to male recipient (HR 0.4, P = .01) and C2C2 ligands (HR 0.4, P = .04) as independent factors predicting relapse. HLA-C ligands were not associated with GVHD or NRM. LFS was 33%, 30%, and 46%, respectively (P = .07). Chemorefractory disease (HR 3.1, P = .0004) and C2C2 group ligand (HR 0.6, P = .06) independently predicted LFS. Treosulfan dose did not predict any SCT outcome. In conclusion, missing HLA-C group 1 ligand is associated with reduced relapse risk, similar NRM and improved LFS, after HLA-matched SCT with treosulfan conditioning in AML/MDS.

Biosimilar Filgrastim (Tevagrastim, XMO2) for Allogeneic Hematopoietic Stem Cell Mobilization and Transplantation in Patients with Acute Myelogenous Leukemia/Myelodysplastic Syndromes.

Human recombinant granulocyte colony-stimulating factor (G-CSF), filgrastim (Neupogen; Amgen, Thousand Oaks, CA, USA), has been widely used for the mobilization of CD34(+) hematopoietic stem cells (HSC) from healthy donors. The experience with biosimilar G-CSF agents in this area is limited. We performed a prospective study assessing Tevagrastim (biosimilar filgrastim, XMO2; Teva, Israel) for mobilization of CD34(+) peripheral blood HSC in HLA-matched healthy sibling donors for transplantation in 24 patients with acute myelogenous leukemia (AML) and high-risk myelodysplastic syndromes (MDS) (NCT01542944). Results were compared to a historical control group of sibling donors who received filgrastim for stem cell mobilization for allogeneic stem cell transplantations in patients with AML and MDS. The healthy donors received Tevagrastim or filgrastim in a dose of 10 µg/kg body weight (BW) subcutaneously for 4 days. The target yields of CD34(+) cells was 5 × 10(6) CD34(+) cells/kg BW of the recipient. A median 10.2 × 10(6) (range, 2.52 to 35.4) and 9.35 × 10(6) (range, 3.7 to 30.6) CD34(+) cells per kg BW were collected in the Tevagrastim and filgrastim groups, respectively. All patients promptly engrafted with a median day of absolute neutrophil count (ANC) of >.5 × 10(9)/L and >1 × 10(9)/L of 13 days (range, 10 to 21) and 13.5 days (range, 10 to 22), respectively in the Tevagrastim group and 12 days (range, 10 to 18) and 13 days (range, 10 to 18) in the filgrastim group, respectively. Platelets reached counts of >20 × 10(9)/L and >50 × 10(9)/L within a median of 14 days (range, 11 to 33) and 17 days (range, 12 to 33) in the Tevagrastim group and 13 (range, 10 to 29) and 15 (range, 10 to 32) days in the filgrastim group, respectively. The donors developed only mild and transient side effects, which were not different between the Tevagrastim study group and the filgrastim historical control group. Similarly, the transplantation-related toxicities and outcomes did not differ between the patients who underwent transplantation with Tevagrastim-mobilized grafts and the filgrastim historical controls. In summary, we observed a similar yield of CD34(+) stem cell mobilization in the Tevagrastim study group and the filgrastim historical control group with similar engraftment kinetic, hematopoietic reconstitution, and transplantation outcome. Tevagrastim administration was safe with minimal side effects and toxicity not different than historical controls. The lack of significant differences for all parameters of stem cell collection, engraftment, and safety with the biosimilar XMO2 Tevagrastim demonstrate the "similarity" of the biosimilar and recombinant human G-CSF in this indication.

Plerixafor (Mozobil): A Stem Cell-Mobilizing Agent for Transplantation in Lymphoma Patients Predicted to Be Poor Mobilizers - A Pilot Study.

Autologous hematopoietic stem cell transplantation is the standard therapy for refractory/relapsed aggressive lymphoma. The initial step of the procedure involves mobilization and collection of hematopoietic stem cells. G-CSF fails to achieve mobilization in 15-25% of lymphoma patients. Plerixafor is a novel CXCR4 antagonist that can promote mobilization. It has been used successfully in patients after the failure of G-CSF. It is reasonable to test whether plerixafor should become the mobilizing agent of choice in patients expected to exhibit difficulties in mobilization. We initiated a study to assess the use of plerixafor as a first-line stem cell mobilizer in 20 elderly or heavily pretreated patients with non-Hodgkin or Hodgkin lymphoma. The minimum defined CD34+ cell dose of ≥2 × 106 cells/kg was achieved by 90% of the patients, and for 83% of them with one apheresis procedure. The target CD34+ dose of ≥5 × 106 cells/kg was achieved by 70% of the patients. The median number of circulating CD34+ cells before and after plerixafor was 14.4 and 42.8 cells/µl, respectively. The post-plerixafor adverse events were mild. All patients promptly engrafted after high-dose chemotherapy treatment. We conclude that plerixafor administration is safe and efficient for upfront mobilization in lymphoma patients predicted to be poor mobilizers.

Liver stiffness measurements predict Sinusoidal Obstructive Syndrome after hematopoietic stem cell transplantation.

Sinusoidal Obstructive Syndrome (SOS) is a life-threatening complication after hematopoietic stem-cell transplantation (HSCT), characterized by post-sinusoidal portal hypertension. FibroScan is used to assess portal hypertension non-invasively. We assessed transient elastography (TE) applicability in diagnosing SOS. The study included 27 adult patients, 11 underwent TE for high SOS risk pre-HSCT, 17 underwent TE post-HSCT due to bilirubin ≥2 mg/dl with no definite diagnosis of SOS. The first group had median Liver Stiffness Measurement (LSM) of 7.4 kPa (range, 3.3-22.5). Based on LSM results, conditioning regimen was modified for six patients and two of them developed SOS. Only one patient who did not have protocol adjustment experienced SOS. No patient with LSM < 7 kPa developed SOS. The second group had median LSM of 7.7 kPa (4.4-31.5). Median LSM after HSCT was significantly higher in patients who subsequently developed established SOS (n = 10) compared to patients who did not (n = 8), with values of 10.7 kPa (5.6-31.5) and 5.9 kPa (4.4-13.8), respectively (p = 0.02). An LSM cut-off of 7.5 kPa had a sensitivity and specificity of 75 and 80% for diagnosing SOS. In conclusion, pre-HSCT LSM can help adjustment of conditioning regimen in patients with high-risk for SOS. Post-HSCT LSM can help in early diagnosis of SOS.

Point of care CD19 chimeric antigen receptor (CAR) T-cells for relapsed/refractory acute myeloid leukemia (AML) with aberrant CD19 antigen expression.

Relapsed/refractory (r/r) acute myeloid leukemia (AML) is associated with poor prognosis. CD19 is a B-cell marker, is aberrantly expressed in AML, mostly with t(8; 21)(q22; q22.1). Here we report the results of a phase 2 study giving point of care produced CD19 CAR T- cells for r/r AML with aberrant expression of CD19 (NCT04257175). Lymphodepletion included fludarabine and cyclophosphamide The response was evaluated by bone marrow (BM) aspiration on day 28. Six patients (5 adults and 1 child) were included. Median number of previous chemotherapy lines was 4 (range, 3-8) and four patients received CAR T-cells 8-18 months post allogeneic hematopoietic stem cell transplantation (allo-HSCT). Cytokine release syndrome (CRS) of any grade occurred in all patients, and 1 patient had grade 3 CRS. Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 2 patients at low grades. Tocilizumab was administered to 2 patients and corticosteroids to 3 patients. Four patients achieved a complete remission (CR), while 2/6 progressed (PD). Three patients (2 with CR and 1 with PD) underwent allo-HSCT (it was the second transplant in 2) 2-5 months post CAR T-cells infusion. The median duration of response in patients achieving CR was 8.5 (range; 3-14) months. However, all patients eventually died within 5 (1-18) months. In conclusion, CD19 CAR T- cell treatment for AML is feasible and safe. However, the response is short and should be followed by allo-HSCT. Hopefully, future long term results will be improved by combining the CAR T- cell therapy with the emerging novel effective anti-leukemic compounds.

Fecal microbiota transplantation in capsules for the treatment of steroid refractory and steroid dependent acute graft vs. host disease: a pilot study.

Acute graft-versus-host disease (aGvHD) is a serious complication of allogeneic hematopoietic stem-cell transplantation with limited treatment options. The gut microbiome plays a critical role in aGvHD pathogenesis. Fecal microbiota transplantation (FMT) has emerged as a potential therapeutic approach to restore gut microbial diversity. In this prospective pilot study, 21 patients with steroid-resistant or steroid-dependent lower gastrointestinal aGvHD received FMT in capsule form. At 28 days after the first FMT, the overall response rate was 52.4%, with 23.8% complete and 28.6% partial responses. However, sustained responses were infrequent, with only one patient remaining aGvHD-free long-term. FMT was generally well-tolerated. Microbiome analysis revealed dysbiosis in pre-FMT patient stool samples, with distinct microbial characteristics compared to donors. Following FMT, there was an increase in beneficial Clostridiales and a decrease in pathogenic Enterobacteriales. These findings highlight the potential of FMT as a treatment option for steroid-resistant aGvHD. Trial registration number NCT #03214289.

Point-of-care anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory follicular lymphoma.

Patients with relapsed/refractory follicular lymphoma (R/R-FL) often require multiple treatment lines. We performed a phase 1b/2 single-center clinical trial of autologous point-of-care anti-CD19 chimeric antigen receptor (CAR) T-cells in R/R-FL patients treated patients with ≥ 2 treatment lines. All 26 patients enrolled received CAR T-cell infusion at a median of 11 days after leukapheresis. Seventy-seven percent of patients had POD24. At enrollment, disease stage was III-IV in 85% of the patients, 77% had high-risk FLIPI score, and 77% had progressive disease. Grade III-IV cytokine release and immune effector cell-associated neurotoxicity syndromes occurred in 12% and 16% of the patients, respectively. Overall response rate at 1-month was 88%. The median follow-up was 15.4 months. One-year overall and progression-free survival were 100% and 63%, respectively. In conclusion, point-of-care CAR T-cell, manufactured within 11 days, induced a high response rate with an acceptable safety profile in patients with high-risk R/R-FL.

Allogeneic Hematopoietic Cell Transplantation after Chimeric Antigen Receptor T Cell Therapy in Large B Cell Lymphoma.

Anti-CD19 chimeric antigen receptor T cell (CAR-T) therapy has transformed the care of patients with relapsed/refractory large B cell lymphoma (LBCL). However, approximately 60% of CAR-T recipients ultimately will experience disease recurrence or progression. Salvage therapies after CAR-T treatment failures are of limited efficacy and have a short duration of response. The objective of the present study was to evaluate the role of allogeneic hematopoietic cell transplantation (allo-HCT) after CAR-T therapy in LBCL patients. This was a multicenter observational study reporting the outcome of 39 adult LBCL patients who underwent allo-HCT following anti-CD19 CAR-T therapy. The median patient age was 47 years (range, 20 to 68 years). HLA-matched sibling, HLA-matched unrelated, and alternative donors were used in 36%, 36%, and 28% of transplantations, respectively. Conditioning regimens were primarily of low or intermediate intensity. Disease status at allo-HCT was complete response in 41%, partial response in 38%, and progressive disease in 21%. Allo-HCT was performed at a median of 127 days (range, 82 to 206 days) after CAR-T therapy. A high incidence of hepatic toxicity (28%), including sinusoidal obstruction syndrome (15.4%; 95% confidence interval; [CI], 6.2% to 28.5%), was observed. The 1-year cumulative incidence of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) was 38.5% (95% CI, 23.2% to 53.6%) and 15.4% (95% CI, 6.1% to 28.5%), respectively. The 2-year cumulative incidence of moderate-severe chronic GVHD was 11.1% (95% CI, 3.3% to 24.3%). Overall, 2-year nonrelapse mortality and relapse/progression incidence were 26% (95% CI, 13% to 41%) and 43% (95% CI, 27% to 59%), respectively. With a median follow-up of 32 months, the 2-year overall survival (OS) and progression-free survival (PFS) were 45% (95% CI, 31% to 66%) and 31% (95% CI, 19% to 50%), respectively. In multivariable analyses, pre-HCT elevated lactate dehydrogenase level and transformed lymphoma were predictive of OS and PFS, respectively. Our data suggest that allo-HCT after anti-CD19 CAR-T treatment failure is feasible with a relatively promising efficacy but possibly high toxicity rate.

Outcomes of first therapy after CD19-CAR-T treatment failure in large B-cell lymphoma.

Persistence or recurrence of large B-cell lymphoma after CD19-CAR-T is common, yet data guiding management are limited. We describe outcomes and features following CAR-T treatment failure. Of 305 adults who received CD19-CAR-T, 182 experienced disease recurrence or progression (1-year cumulative incidence 63% [95%CI: 57-69]). Of 52 post-CAR-T biopsies evaluated by flow cytometry, 49 (94%) expressed CD19. Subsequent anti-cancer treatment was administered in 135/182 (74%) patients with CAR-T treatment failure. Median OS from the first post-CAR-T treatment was 8 months (95%CI 5.6-11.0). Polatuzumab-, standard chemotherapy-, and lenalidomide-based treatments were the most common approaches after CAR-T. No complete responses (CRs) were observed with conventional chemotherapy, while CR rates exceeding 30% were seen following polatuzumab- or lenalidomide-based therapies. Factors associated with poor OS among patients treated post-CAR-T were pre-CAR-T bulky disease (HR 2.27 [1.10-4.72]), lack of response to CAR-T (2.33 [1.02-5.29]), age >65 years (HR 2.65 [1.49-4.73]) and elevated LDH at post-CAR-T treatment (HR 2.95 [1.61-5.38]). The presence of ≥2 of these factors was associated with inferior OS compared to ≤1 (56% vs. 19%). In this largest analysis to date of patients who progressed or relapsed after CD19-CAR-T, survival is poor, though novel agents such as polatuzumab and lenalidomide may have hold promise.