Post-transplant cyclophosphamide separates graft-versus host disease and graft versus leukemia effects after HLA-matched stem-cell transplantation for acute myeloid leukemia.

The association of graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effects after allogeneic stem-cell transplantation (SCT) is well-established but was not confirmed in the modern era and following post-transplant cyclophosphamide (PTCy). We assessed GVHD/ GVL association in AML patients following HLA-matched SCT with standard calcineurin-based (n = 12,653, 57% with additional in-vivo T-cell depletion) or PTCy-based (n = 508) GVHD prophylaxis. Following standard prophylaxis, acute GVHD grade II-IV and III-IV, chronic GVHD, and extensive chronic GVHD rates were 23.8%, 7.5%, 37.0%, and 16.3%, respectively. Acute GVHD grade II and III-IV were associated with lower relapse [hazard-ratio (HR) 0.85, P = 0.002; HR 0.76, P = 0.003, respectively)], higher non-relapse mortality (NRM) (HR 1.5, P < 0.001; HR 6.21, P < 0.001) and lower overall survival (OS) (HR 1.49, P < 0.001; HR 6.1, P < 0.001). Extensive chronic GVHD predicted lower relapse (HR 0.69, P < 0.001), higher NRM (HR 2.83, P < 0.001), and lower OS (HR 2.74, P < 0.001). Following PTCy, GVHD rates were 22.8%, 6.2%, 35.5%, and 17.7%, respectively. Acute GVHD was not associated with relapse (HR 1.37, P = 0.15) but predicted higher NRM (HR 3.34, P < 0.001) and lower OS (HR 1.92, P = 0.001). Chronic GVHD was not prognostic for these outcomes. In conclusion, GVHD and GVL are strongly associated with contemporary SCT. However, following PTCy, GVHD is not associated with reduced relapse.

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.

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 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-Hodgkins 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 (BCL-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 LDH, 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.

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.

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.

Generation of Non-Alloreactive Antiviral Central Memory CD8 Human Veto T Cells for Cell Therapy.

Previous studies in mice demonstrated that CD8 T cells exhibit marked veto activity enhancing engraftment in several models for T cell-depleted bone marrow (TDBM) allografting. To reduce the risk of graft-versus-host disease (GVHD) associated with allogeneic CD8 veto T cells, these studies made use of naive CD8 T cells stimulated against third-party stimulators under cytokine deprivation and subsequent expansion in the presence of IL-15. More recently, it was shown that mouse CD8 veto T cells can be generated by stimulating CD8 memory T cells from ovalbumin immunized mice under cytokine deprivation, using ovalbumin as a third-party antigen. These cells also exhibited substantial enhancement of BM allografting without GVHD. In this study, we tested the hypothesis that stimulation and expansion of human CD8 memory T cells under IL-15 and IL-7 deprivation during the early phase of activation against recall viral antigens can lead to substantial loss of alloreactive T clones while retaining marked veto activity. Memory CD8 T cells were enriched by removal of CD45RA+, CD4+, and CD56+ cells from peripheral blood of cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-positive donors. In parallel, CD14+ monocytes were isolated; differentiated into mature dendritic cells (mDCs); pulsed with a library of CMV, EBV, adenovirus, and BK virus peptides; and irradiated. The CD8 T cell-enriched fraction was then cultured with the pulsed mDCs in the presence of IL-21 for 3 days, after which IL-15 and IL-7 were added. After 12 days of culture, the cells were tested by limiting dilution analysis for the frequency of alloreactive T cell clones and their veto activity. In preclinical runs using GMP reagents, we established that within 12 days of culture, a large number of highly homogenous CD8 T cells, predominantly expressing a central memory phenotype, could be harvested. These cells exhibited marked veto activity in vitro and >3-log depletion of alloreactivity. Based on these preclinical data, a phase 1-2 clinical trial was initiated to test the safety and efficacy of these antiviral CD8 central memory veto cells in the context of nonmyeloablative (NMA) T cell-depleted haploidentical hematopoietic stem cell transplantation (HSCT). In 2 validation runs and 11 clinical runs using GMP reagents, >1 × 1010 cells were generated from a single leukapheresis in 12 out of 13 experiments. At the end of 12 days of culture, there were 97 ± 2.5% CD3+CD8+ T cells, of which 84 ± 9.0% (range, 71.5% to 95.1%) exhibited the CD45RO+CD62L+ CM phenotype. Antiviral activity tested by intracellular expression of INF-γ and TNF-α and showed an average of 38.8 ± 19.6% positive cells on 6 hours of stimulation against the viral peptide mixture. Our results demonstrate a novel approach for depleting alloreactive T cell clones from preparations of antiviral CD8 veto cells. Based on these results, a phase 1-2 clinical trial is currently in progress to test the safety and efficacy of these veto cells in the context of NMA haploidentical T cell-depleted HSCT. Studies testing the hypothesis that these non-alloreactive CD8 T cells could potentially offer a platform for off-the-shelf veto chimeric antigen receptor T cell therapy in allogenic recipients, are warranted.

Defining Current Patterns of Blood Product Use during Intensive Induction Chemotherapy in Newly Diagnosed Acute Myeloid Leukemia Patients.

Introduction: Blood product transfusion retains a critical role in the supportive care of patients with acute myeloid leukemia (AML). Whereas previous studies have shown increased transfusion dependency to portend inferior outcome, predictive factors of an increased transfusion burden and the prognostic impact of transfusion support have not been assessed recently. Methods/Patients: We performed a retrospective analysis on a recent cohort of patients given intensive induction chemotherapy in 2014-2022. Results: The analysis comprised 180 patients with a median age of 57 years with 80% designated as de novo AML. Fifty-four patients (31%) were FLT3-ITD mutated, and 73 patients (42%) harbored NPM1. Favorable risk and intermediate risk ELN 2017 patients accounted for 43% and 34% of patients, respectively. The median number of red blood cell (RBC) and platelet units given during induction were 9 and 7 units, respectively. Seventeen patients (9%) received cryoprecipitate, and fresh frozen plasma (FFP) was given to 12 patients (7%). Lower initial hemoglobin and platelet levels were predictive of increased use of RBC (p < 0.0001) and platelet transfusions (p < 0.0001). FFP was significantly associated with induction related mortality (42% vs. 5%; p < 0.0001) and with FLT3-ITD (72% vs. 28%; p = 0.004). Blood group AB experienced improved mean overall survival compared to blood group O patients (4.1 years vs. 2.8 years; p = 0.025). In multivariate analysis, increased number of FFP (hazard ratio [HR], 4.23; 95% confidence interval [CI], 2.1-8.6; p < 0.001) and RBC units (HR, 1.8; 95% CI, 1.2-2.8; p = 0.008) given was associated with inferior survival. Conclusion: Transfusion needs during induction crucially impact the clinical trajectory of AML patients.

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 stem cell transplantation for NK/T-cell lymphoma: an international collaborative analysis.

Natural killer/T-cell lymphomas (NKTCL) represent rare and aggressive lymphoid malignancies. Patients (pts) with relapsed/refractory disease after Asparaginase (ASPA)-based chemotherapy have a dismal prognosis. To better define the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT), we conducted a retrospective analysis of data shared with the European Society for Blood and Marrow Transplantation (EBMT) and cooperating Asian centers. We identified 135 pts who received allo-HSCT between 2010 and 2020. Median age was 43.4 years at allo-HSCT, 68.1% were male. Ninety-seven pts (71.9 %) were European, 38 pts (28.1%) Asian. High Prognostic Index for NKTCL (PINK) scores were reported for 44.4%; 76.3% had >1 treatment, 20.7% previous auto-HSCT, and 74.1% ASPA-containing regimens prior to allo-HSCT. Most (79.3%) pts were transplanted in CR/PR. With a median follow-up of 4.8 years, 3-year progression-free(PFS) and overall survival were 48.6% (95%-CI:39.5-57%) and 55.6% (95%-CI:46.5-63.8%). Non-relapse mortality at 1 year was 14.8% (95%-CI:9.3-21.5%) and 1-year relapse incidence 29.6% (95%-CI:21.9-37.6%). In multivariate analyses, shorter time interval (0-12 months) between diagnosis and allo-HSCT [HR = 2.12 (95%-CI:1.03-4.34); P = 0.04] and transplantation not in CR/PR [HR = 2.20 (95%-CI:0.98-4.95); P = 0.056] reduced PFS. Programmed cell death protein 1(PD-1/PD-L1) treatment before HSCT neither increased GVHD nor impacted survival. We demonstrate that allo-HSCT can achieve long-term survival in approximately half of pts allografted for NKTCL.

The occurrence of thrombosis during intensive chemotherapy treatment for acute myeloid leukemia patients does not impact on long-term survival.

Venous thromboembolism (VTE) is frequently seen in acute myeloid leukemia (AML) patients and presents a significant clinical challenge. The association of VTE during intensive chemotherapy with risk models such as the Medical Research Council (MRC) cytogenetic-based assessment and the European LeukemiaNet (ELN) 2017 molecular risk model have not been rigorously evaluated. Additionally, there is a paucity of data pertaining to the long-term prognostic impact of VTE in AML patients. We performed an analysis of baseline parameters of AML patients diagnosed with VTE during intensive chemotherapy and compared them with patients without VTE. The analyzed cohort consisted of 335 newly diagnosed AML patients with a median age of 55 years. Thirty-five patients (11%) were classified as MRC favorable risk, 219 (66%) patients as intermediate risk, 58 patients (17%) as adverse risk. Per ELN 2017, 132 patients (40%) had favorable risk disease, 122 patients (36%) intermediate risk, and 80 patients (24%) had adverse risk. VTE was seen in 33 patients (9.9%), occurring mostly during induction (70%), and required catheter removal in 9 patients (28%). Baseline clinical, laboratory, molecular, and ELN 2017 parameters were not significantly different groups. However, MRC intermediate-risk group patients were significantly more likely to experience thrombosis compared to favorable risk and adverse risk patients (12.8% versus 5.7% and 1.7%, respectively; p = 0.049). Median overall survival was not significantly impacted by the diagnosis of thrombosis (3.7 years versus 2.2 years; p = 0.47). VTE is tightly associated with temporal and cytogenetic parameters in AML but does not significantly impact on long-term outcomes.

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.

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.

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.

CXCL13 chemokine is a novel player in multiple myeloma osteolytic microenvironment, M2 macrophage polarization, and tumor progression.

BACKGROUND: We assessed the mechanism by which multiple myeloma (MM) shapes the bone marrow (BM) microenvironment and affects MΦ polarization. METHODS: In vivo xenograft model of BM-disseminated human myeloma, as well as analysis of MM cell lines, stromal components, and primary samples from patients with MM, was utilized. RESULTS: Analysis of the BM from MM-bearing mice inoculated with human CXCR4-expressing RPMI8226 cells revealed a significant increase in M2 MΦ cell numbers (p < 0.01). CXCL13 was one of the most profoundly increased factors upon MM growth with increased levels in the blood of MM-bearing animals. Myeloid cells were the main source of the increased murine CXCL13 detected in MM-infiltrated BM. MM cell lines induced CXCL13 and concurrent expression of M2 markers (MERTK, CD206, CD163) in co-cultured human MΦ in vitro. Interaction with MΦ reciprocally induced CXCL13 expression in MM cell lines. Mechanistically, TGFß signaling was involved in CXCL13 induction in MM cells, while BTK signaling was implicated in MM-stimulated increase of CXCL13 in MΦ. Recombinant CXCL13 increased RANKL expression and induced TRAP+ osteoclast (OC) formation in vitro, while CXCL13 neutralization blocked these activities. Moreover, mice inoculated with CXCL13-silenced MM cells developed significantly lower BM disease. Reduced tumor load correlated with decreased numbers of M2 MΦ in BM, decreased bone disease, and lower expression of OC-associated genes. Finally, higher levels of CXCL13 were detected in the blood and BM samples of MM patients in comparison with healthy individuals. CONCLUSIONS: Altogether, our findings suggest that bidirectional interactions of MΦ with MM tumor cells result in M2 MΦ polarization, CXCL13 induction, and subsequent OC activation, enhancing their ability to support bone resorption and MM progression. CXCL13 may thus serve as a potential novel target in MM.

Point-of-care CAR T-cell therapy as salvage strategy for out-of-specification tisagenlecleucel.

Tisagenlecleucel (tisa-cel) is an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for patients with relapsed/refractory large B-cell lymphoma. Outcomes of patients with out-of-commercial specification (OOS) CAR T products are not well characterized. We therefore assessed 37 adult patients who underwent leukapheresis for tisa-cel therapy in a single center. In nine (24%) patients, manufactured tisa-cel was considered OOS. Three of them (33%) received tisa-cel after institutional review board approval; 2/9 (22%) did not receive tisa-cel due to disease progression; and 4/9 (44%) received academic point-of-care (POC) CAR T-cell as salvage therapy, at a median of 35 days following OOS notification. Three of those four patients achieved a complete response. In univariate analysis, risk factors for OOS were ≥ 4 prior therapies or previous bendamustine exposure. In conclusion, we report high OOS incidence of 24% in real-life setting. Forty-four percent of those patients received POC CAR T-cell as salvage therapy.

Contemporary evaluation of acute myeloid leukemia patients with long-term survival exceeding 5 years.

OBJECTIVES: Define clinical and laboratory attributes of acute myeloid leukemia (AML) patients with long-term survival exceeding five years and compare them with AML patients succumbing to disease within 2 years of diagnosis. METHODS: A retrospective analysis of AML patients alive at least five years from the time of initial diagnosis. Baseline clinical data were compared with patients who died within 2 years of diagnosis. RESULTS: The long-term cohort consisted of 93 patients treated in 2007-2016 with a median follow-up duration of 7.7 years (range 5-13.6 years). European LeukemiaNet (ELN) 2017 favorable risk patients accounted for 60% of the cohort. All long-term survivors achieved remission following induction chemotherapy. Multivariate analysis showed that compared with 132 patients experiencing death within 2 years of diagnosis, long-term survivors were more likely to be of younger age [odds ratio (OR), 0.92; 95% confidence interval (CI), 0.9-0.95; p < 0.001], have a lower initial WBC count (OR, 0.58; 95% CI, 0.43-0.79; p = 0.0004), undergo an allogeneic stem cell transplantation (OR, 7.95; 95% CI, 3.07-20.59; p < 0.0001), and harbor favorable risk cytogenetics (OR, 0.03; 95% CI, 0.006-0.23; p = 0.0004). CONCLUSIONS: Long-term survival of AML is seen in a distinct demographic and biologic patient subset.

Molecular and Functional Signatures Associated with CAR T Cell Exhaustion and Impaired Clinical Response in Patients with B Cell Malignancies.

Despite the high rates of complete remission following chimeric antigen receptor (CAR) T cell therapy, its full capacity is currently limited by the generation of dysfunctional CAR T cells. Senescent or exhausted CAR T cells possess poor targeting and effector functions, as well as impaired cell proliferation and persistence in vivo. Strategies to detect, prevent or reverse T cell exhaustion are therefore required in order to enhance the effectiveness of CAR T immunotherapy. Here we report that CD19 CAR T cells from non-responding patients with B cell malignancies show enrichment of CD8+ cells with exhausted/senescent phenotype and display a distinct transcriptional signature with dysregulation of genes associated with terminal exhaustion. Furthermore, CAR T cells from non-responding patients exhibit reduced proliferative capacity and decreased IL-2 production in vitro, indicating functional impairment. Overall, our work reveals potential mediators of resistance, paving the way to studies that will enhance the efficacy and durability of CAR T therapy in B cell malignancies.

Point-of-care anti-CD19 CAR T-cells for treatment of relapsed and refractory aggressive B-cell lymphoma.

Anti CD19 chimeric antigen receptor (CAR) T-cell therapy has transformed the care of relapsed and refractory aggressive B-cell lymphoma. However, financial toxicity and manufacturing time represent barriers to its widespread implementation. Study applicability, toxicity, and efficacy of a locally produced autologous CD19-directed CAR T-cell product were studied. We performed a phase 1b/2 clinical trial with a point-of-care (POC) CAR T-cell product that contains a CD28 costimulatory domain. Adult patients with aggressive B-cell lymphoma or transformed low-grade lymphoma who received at least 2 prior regimens were eligible. A total of 73 patients, with a median age of 49 years, met inclusion criteria. CAR T-cell production time from apheresis was 10 days (interquartile range 10-11), negating the need for bridging chemotherapy. Overall and complete response rates were 62.5% and 37.5%. Median progression-free and overall survival were 3.7 and 12.1 months, respectively. Overall and progression-free survival at 12 months were 52.1% (confidence interval [CI]: 40.8%-66.5%) and 40% (CI: 30%-53.7%), respectively. Patients who achieved response had longer progression-free and overall survival. Grade 3-4 cytokine release syndrome was observed in 9.5% of the patients, and immune effector cell-associated neurotoxicity syndrome grade 3-4 in 21.9%. No deaths occurred due to CAR T-cell toxicity. Fifteen patients (20%) underwent allogeneic stem cell transplantation at a median time of 60 days after CAR T-cell therapy; 8 were alive at last follow-up. Of the 6 patients who underwent the transplantation in complete response 2 deceased because of toxicity. POC CAR T-cells are a feasible therapeutic option in aggressive B-cell lymphoma. They provide good efficacy while minimizing production time and the need for bridging therapy.

Evaluating outcomes of adult patients with acute lymphoblastic leukemia and lymphoblastic lymphoma treated on the GMALL 07/2003 protocol.

Chemotherapy-based approaches still constitute an essential feature in the treatment paradigm of adult acute lymphoblastic leukemia (ALL). The German Multicenter Study Group (GMALL) is a well-established protocol for ALL. In this study, we assessed our recent experience with the GMALL 07/2003 protocol reviewing all adult ALL patients who were treated with GMALL in three major centers in Israel during 2007-2020. The analysis comprised 127 patients with a median age of 41 years (range 17-83). Sixty-two were B-ALL (49%), 20 (16%) patients were Philadelphia chromosome positive ALL, and 45 (35%) were T-ALL. The 2-year and 5-year overall survival rates were 71% and 57%, respectively. The 2-year relapse rate was 30% with 2-year and 5-year leukemia-free survival rates of 59% and 50%, respectively. Adolescents and young adults experienced significantly longer overall survival (84 months versus 51 months; p=0.047) as well as leukemia-free survival compared with older patients (66 months versus 54 months, p=0.003; hazard ratio=0.39, 95% confidence interval, 0.19-0.79; p=0.009). T-ALL patients had longer survival compared to B-ALL patients while survival was comparable among Philadelphia chromosome positive patients and Philadelphia chromosome negative patients. An increased number of cytogenetic clones at diagnosis were tightly associated with adverse prognosis (15-month survival for ≥2 clones versus 81 months for normal karyotype; p=0.003). Positive measurable residual disease studies following consolidation were predictive for increased risk of relapse (64% versus 22%; p=0.003) and shorter leukemia-free survival (11 months versus 42 months; p=0.0003). While GMALL is an effective adult regimen, a substantial patient segment still experiences relapse.