Identification of predictive models including polymorphisms in cytokines genes and clinical variables associated with post-transplant complications after identical HLA-allogeneic stem cell transplantation.

Backgrounds: Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative therapy for hematological malignancies, it can be associated with relevant post-transplant complications. Several reports have shown that polymorphisms in immune system genes are correlated with the development of post-transplant complications. Within this context, this work focuses on identifying novel polymorphisms in cytokine genes and developing predictive models to anticipate the risk of developing graft-versus-host disease (GVHD), transplantation-related mortality (TRM), relapse and overall survival (OS). Methods: Our group developed a 132-cytokine gene panel which was tested in 90 patients who underwent an HLA-identical sibling-donor allo-HSCT. Bayesian logistic regression (BLR) models were used to select the most relevant variables. Based on the cut-off points selected for each model, patients were classified as being at high or low-risk for each of the post-transplant complications (aGVHD II-IV, aGVHD III-IV, cGVHD, mod-sev cGVHD, TRM, relapse and OS). Results: A total of 737 polymorphisms were selected from the custom panel genes. Of these, 41 polymorphisms were included in the predictive models in 30 cytokine genes were selected (17 interleukins and 13 chemokines). Of these polymorphisms, 5 (12.2%) were located in coding regions, and 36 (87.8%) in non-coding regions. All models had a statistical significance of p<0.0001. Conclusion: Overall, genomic polymorphisms in cytokine genes make it possible to anticipate the development all complications studied following allo-HSCT and, consequently, to optimize the clinical management of patients.

ASTCT Consensus Recommendations on Testing and Treatment of Patients with Donor-specific Anti-HLA Antibodies.

Donor-specific anti-HLA antibodies (DSA) are an important cause of engraftment failure and may negatively impact survival outcomes of patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) using an HLA-mismatched allograft. The incidence of DSA varies across studies, depending on individual factors, detection or identification methods and thresholds considered clinically relevant. Although DSA testing by multiplex bead arrays remains semiquantitative, it has been widely adopted as a standard test in most transplant centers. Additional testing to determine risk of allograft rejection may include assays with HLA antigens in natural conformation, such as flow cytometric crossmatch, and/or antibody binding assays, such as C1q testing. Patients with low level of DSA (<2,000 mean fluorescence intensity; MFI) may not require treatment, while others with very high level of DSA (>20,000 MFI) may be at very high-risk for engraftment failure despite current therapies. By contrast, in patients with moderate or high level of DSA, desensitization therapy can successfully mitigate DSA levels and improve donor cell engraftment rate, with comparable outcomes to patients without DSA. Treatment is largely empirical and multimodal, involving the removal, neutralization, and blocking of antibodies, as well as inhibition of antibody production to prevent activation of the complement cascade. Desensitization protocols are based on accumulated multicenter experience, while prospective multicenter studies remain lacking. Most patients require a full intensity protocol that includes plasma exchange, while protocols relying only on rituximab and intravenous immunoglobulin may be sufficient for patients with lower DSA levels and negative C1q and/or flow cytometric crossmatch. Monitoring DSA levels before and after HSCT could guide preemptive treatment when high levels persist after stem cell infusion. This paper aims to standardize current evidence-based practice and formulate future directions to improve upon current knowledge and advance treatment for this relatively rare, but potentially serious complication in allogeneic HSCT recipients.

Use of Eltrombopag to Improve Thrombocytopenia and Tranfusion Requirement in Anti-CD19 CAR-T Cell-Treated Patients.

Background/Objectives: Immune effector cell-associated hematotoxicity (ICAHT) is a frequent adverse event after chimeric antigen receptor (CAR)-T cell therapy. Grade ≥ 3 thrombocytopenia occurs in around one-third of patients, and many of them become platelet transfusion-dependent. Eltrombopag is a thrombopoietin receptor agonist (TPO-RA) able to accelerate megakaryopoiesis, which has been used successfully in patients with bone marrow failure and immune thrombocytopenia (ITP). Its role in managing thrombocytopenia and other cytopenias in CAR-T cell-treated patients has been scarcely addressed. Our aim was to report the safety and efficacy of this approach in patients included in the Spanish Group for Hematopoietic Transplantation and Cellular Therapy (GETH-TC) registry. Methods: This is a retrospective, multicenter, observational study. Patients who developed platelet transfusion dependence subsequently to CAR-T cells and received eltrombopag to improve platelet counts were recruited in 10 Spanish hospitals. Results: Thirty-eight patients were enrolled and followed up for a median (interquartile range [IQR]) of 175 (99, 489) days since CAR-T cell infusion. At the moment eltrombopag was indicated, 18 patients had thrombocytopenia and another severe cytopenia, while 8 patients had severe pancytopenia. After 32 (14, 38) days on eltrombopag, 29 (76.3%) patients recovered platelet transfusion independence. The number of platelet units transfused correlated with the time needed to restore platelet counts higher than 20 × 109/L (Rho = 0.639, p < 0.001). Non-responders to eltrombopag required more platelet units (58 [29, 69] vs. 12 [6, 26] in responders, p = 0.002). Nineteen out of twenty-three (82.6%) patients recovered from severe neutropenia after 22 (11, 31) days on eltrombopag. Twenty-nine out of thirty-five (82.9%) patients recovered red blood cell (RBC) transfusion independence after 29 (17, 44) days. Seven patients recovered all cell lineages while on treatment. No thromboembolic events were reported. Only two transient toxicities (cholestasis, hyperbilirubinemia) were reported during eltrombopag treatment, none of which compelled permanent drug withdrawal. Conclusions: Eltrombopag could be safely used to manage thrombocytopenia and accelerate transfusion independence in CAR-T cell-treated patients.

Efficacy and safety of bendamustine-containing bridging therapy in R/R LBCL patients receiving CD19 CAR T-cells.

Bridging therapy (BT) after leukapheresis is required in most relapsed/refractory (R/R) large B-cell lymphoma (LBCL) patients receiving chimeric antigen receptor (CAR) T cells. Bendamustine-containing regimens are a potential BT option. We aimed to assess if this agent had a negative impact on CAR-T outcomes when it was administered as BT. We included R/R LBCL patients from six centers who received systemic BT after leukapheresis from February 2019 to September 2022; patients who only received steroids or had pre-apheresis bendamustine exposure were excluded. Patients were divided into two BT groups, with and without bendamustine. Separate safety and efficacy analyses were carried out for axi-cel and tisa-cel. Of 243 patients who received BT, bendamustine (benda) was included in 62 (26%). There was a higher rate of BT progressors in the non-benda group (62% vs. 45%, p = 0.02). Concerning CAR-T efficacy, complete responses were comparable for benda versus non-benda BT cohorts with axi-cel (70% vs. 53%, p = 0.12) and tisa-cel (44% vs. 36%, p = 0.70). Also, 12-month progression-free and overall survival were not significantly different between BT groups with axi-cel (56% vs. 43% and 71% vs. 63%) and tisa-cel (25% vs. 26% and 52% vs. 48%); there were no differences when BT response was considered. CAR T-cell expansion for each construct was similar between BT groups. Regarding safety, CRS G ≥3 (6% vs. 6%, p = 0.79), ICANS G ≥3 (15% vs. 17%, p = 0.68), severe infections, and neutropenia post-infusion were comparable among BT regimens. BT with bendamustine-containing regimens is safe for patients requiring disease control during CAR T-cell manufacturing.

Anti-CD19 CAR-T Cell Therapy in Elderly Patients: Multicentric Real-World Experience from GETH-TC/GELTAMO.

Chimeric antigen receptor (CAR)-T cell therapy is approved for the treatment of relapsed/refractory (R/R) large B cell lymphoma (LBCL). However, elderly patients might not be candidates for this therapy due to its toxicity, and criteria for candidate selection are lacking. Our aim was to analyze efficacy and toxicity results of CAR-T cell therapy in the population of patients 70 years and older as compared to those obtained in younger patients in the real-world setting. A multicentric retrospective study was performed including patients with R/R aggressive LBCL who received commercial CAR-T cell therapy with either tisagenlecleucel or axicabtagene ciloleucel within the Spanish Group of Hematopoietic Transplant and Cell Therapy/Spanish Group of Lymphomas and Autologous Transplant (GETH-TC/GELTAMO) centers between 2019 and 2023. As of August 2023, 442 adult patients with aggressive LBCL underwent apheresis for CAR-T cell therapy as third or subsequent line and follow-up data was collected. Of 412 infused patients, 71 (17%) were 70 years or older. Baseline characteristics, product selection, and characteristics at apheresis (including disease status, Ann Arbor stage, revised international prognosis index (R-IPI), bulky disease, lactate dehydrogenase [LDH] and ECOG [Eastern Cooperative Group performance status]) were comparable between groups. Median time from both approval to infusion and apheresis to infusion did not differ. No differences were found between groups in overall and complete response rates at 1 and 3 months. With a median follow-up of 12.2 months (range 1-44), 12-month progression-free survival (PFS) and overall survival (OS) were comparable between groups (35.2% in <70 years vs. 35.9% in ≥70 years (P = .938) and 51.1% and 52.1% (P = .885), respectively). Age ≥70 years did not affect PFS (hazard ratio (HR) 0.98, P = .941) and OS (HR 0.97, P = .890) in the univariate and multivariate analysis. Cytokine release syndrome (CRS) was observed in 82% of patients <70 years old and 84.5% in ≥ 70 years old (P = .408). Grade ≥3 CRS was more frequent in the older group (5% vs. 15%, P = .002). In the multivariate analysis, age ≥70 years was associated with an increased risk of grade ≥3 CRS (OR 3.7, P = .013). No differences were observed in terms of overall neurotoxicity (35% vs. 42%, P = .281) or grade ≥3 (12% vs. 17%, P = .33). The proportion of patients with infections, admission to the intensive care unit within the first month, and non-relapse mortality were similar between both groups. CAR-T cell therapy in patients older than 70 years showed similar efficacy to that observed in younger patients in the real-world setting. However, age ≥70 years was an independent risk factor for grades 3-4 CRS. The need for additional strategies to reduce toxicity in this population should be addressed in future studies.

Real-World Experience with Isavuconazole in Allogeneic Stem Cell Transplantation in Spain.

Invasive fungal infections (IFI) pose a significant complication after hematopoietic stem cell transplantation (HSCT). Isavuconazole (ISV) is a new generation azole with a favourable adverse effect and interaction profile approved for the treatment of invasive aspergillosis and mucormycosis. We analyzed the indications, effectiveness, adverse event profile and drug interaction management of ISV in the real-world setting in adults who received allogeneic-HSCT (allo-HSCT) within the Spanish Group of HSCT and Cell Therapy (GETH-TC). We conducted a multicenter retrospective study of all consecutive adult allo-HSCT recipients (≥18 years) who received ISV either for IFI treatment or prophylaxis, from December 2017 to August 2021, in 20 centers within the Spanish Group of Hematopoietic Stem Cell Transplantation and Cell Therapy (GETH-TC). A total of 166 adult allografted patients who received ISV from 2017 to 2021 were included. Median age was 48 years with 43% females. In 81 (49%) patients, ISV was used for treatment of IFI, and in 85 (51%) for prophylaxis. Median duration of ISV administration for IFI treatment was 57 days (range 31-126) and 86 days (range 33-196) for prophylaxis. Most frequent indication for treatment was invasive aspergillosis (78%), followed by mucormycosis (6%). Therapeutic success (45%) was the most frequent reason for ISV withdrawal. In the prophylaxis group, the resolution of IFI risk factors was the most frequent reason for withdrawal (62%). Six (7%) breakthrough IFI were reported. The majority of patients (80%) presented pharmacologic interactions. Twenty-one patients (13%) reported adverse events related to ISV, mainly liver biochemistry abnormalities, which led to ISV withdrawal in 7 patients (4%). ISV was effective and well tolerated for IFI treatment and prophylaxis, with a manageable interaction profile.

Post-transplant cyclophosphamide compared to sirolimus/tacrolimus in reduced intensity conditioning transplants for patients with lymphoid malignancies.

Despite novel cellular and immunomodulatory therapies, allogeneic hematopoietic stem cell transplantation (HSCT) remains a treatment option for lymphoid malignancies. Post-transplant cyclophosphamide (PTCY) is increasingly employed for graft vs. host disease (GVHD) prophylaxis. This study aims to evaluate the safety and efficacy of PTCY in reduce intensity (RIC) HSCT for patients with lymphoid neoplasms compared to sirolimus with tacrolimus (SIR/TAC). The primary endpoint was to compare grade III-IV acute GVHD, severe chronic GVHD, and relapse-free survival (GRFS) between the two GVHD prophylaxis strategies. This study, conducted from January 2012 to December 2020, included 171 consecutive patients (82 in the PTCY and 89 in the SIR/TAC group). Results revealed a significantly decreased incidence of moderate and severe forms of chronic GVHD in PTCY cohort (5.8% [95% CI, 1.8 to 13.1]) versus the SIR/TAC cohort (39.6% [95% CI, 29.3 to 49.7] (p < 0.001)). Other outcomes, including GRFS (PTCY [45.9% (95% CI, 35.8-58.7)] and SIR/TAC groups [36.8% (95% CI, 28-48.4)], (p = 0.72)), non-relapse mortality (NRM), relapse and overall survival (OS) were similar in both groups. Interestingly, the failure to achieve GRFS was mainly attributed to GVHD in the SIR/TAC group, while disease relapse was the primary reason in the PTCY cohort.

Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease after Unmanipulated Haploidentical Hematopoietic Stem Cell Transplantation with Post-Transplantation Cyclophosphamide: A Study on Behalf of the Spanish Hematopoietic Stem Cell Transplantation and Cellular Therapy Group (GETH).

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a life-threatening complication after both autologous and allogeneic hematopoietic stem cell transplantation (HSCT). However, its characterization after haploidentical HSCT (haplo-HSCT) with post-transplantation cyclophosphamide (PT-Cy) is scarce. This study aimed to describe characteristics and outcomes of patients with SOS/VOD after haplo-HSCT with PT-Cy. We conducted a retrospective study of 797 patients undergoing a haplo-HSCT with PT-Cy between 2007 and 2019 in 9 centers in Spain. SOS/VOD was defined according to modified Seattle, Baltimore, or revised European Society for Blood and Marrow Transplantation (EBMT) criteria. Severity was graded retrospectively according to revised EBMT severity criteria into 4 categories: mild, moderate, severe, and very severe. From a total of 797 haplo-HSCTs performed, 46 patients (5.77%) were diagnosed with SOS/VOD at a median of 19 days (range, 4 to 84 days) after transplantation. Based on revised EBMT severity criteria, the SOS/VOD cases were classified as mild (n = 4; 8.7%), moderate (n = 10; 21.7%), severe (n = 12; 26.1%), and very severe (n = 20; 43.5%). Overall, 30 patients (65%) achieved SOS/VOD complete response, 25 (83%) of whom were treated with defibrotide. Twenty patients (43%) died before day +100 post-HSCT. Death was attributed to SOS/VOD in 11 patients, and 5 patients died of other causes without resolution of SOS/VOD. The incidence of SOS/VOD after haplo-HSCT with PT-Cy was comparable to those reported after HLA-identical HSCT series. Most of the patients developed very severe SOS/VOD according to revised EBMT severity criteria. Despite a promising SOS/VOD complete response (CR) rate (65%), 100-day mortality remained high (43%), indicating that further improvement in the management of this potentially fatal complication is needed.

Dynamics of virological and immunological markers of HIV persistence after allogeneic haematopoietic stem-cell transplantation in the IciStem cohort: a prospective observational cohort study.

BACKGROUND: Allogeneic haematopoietic stem-cell transplantation (allo-HSCT) markedly reduces HIV reservoirs, but the mechanisms by which this occurs are only partly understood. In this study, we aimed to describe the dynamics of virological and immunological markers of HIV persistence after allo-HSCT. METHODS: In this prospective observational cohort study, we analysed the viral reservoir and serological dynamics in IciStem cohort participants with HIV who had undergone allo-HSCT and were receiving antiretroviral therapy, ten of whom had received cells from donors with the CCR5Δ32 mutation. Participants from Belgium, Canada, Germany, Italy, the Netherlands, Spain, Switzerland, and the UK were included in the cohort both prospectively and retrospectively between June 1, 2014 and April 30, 2019. In the first 6 months after allo-HSCT, participants had monthly assessments, with annual assessments thereafter, with the protocol tailored to accommodate for the individual health status of each participant. HIV reservoirs were measured in blood and tissues and HIV-specific antibodies were measured in plasma. We used the Wilcoxon signed-rank test to compare data collected before and after allo-HSCT in participants for whom longitudinal data were available. When the paired test was not possible, we used the Mann-Whitney U test. We developed a mathematical model to study the factors influencing HIV reservoir reduction in people with HIV after allo-HSCT. FINDINGS: We included 30 people with HIV with haematological malignancies who received a transplant between Sept 1, 2009 and April 30, 2019 and were enrolled within the IciStem cohort and included in this analysis. HIV reservoirs in peripheral blood were reduced immediately after full donor chimerism was achieved, generally accompanied by undetectable HIV-DNA in bone marrow, ileum, lymph nodes, and cerebrospinal fluid, regardless of donor CCR5 genotype. HIV-specific antibody levels and functionality values declined more slowly than direct HIV reservoir values, decaying significantly only months after full donor chimerism. Mathematical modelling suggests that allogeneic immunity mediated by donor cells is the main viral reservoir depletion mechanism after massive reservoir reduction during conditioning chemotherapy before allo-HSCT (half-life of latently infected replication-competent cells decreased from 44 months to 1·5 months). INTERPRETATION: Our work provides, for the first time, data on the effects of allo-HSCT in the context of HIV infection. Additionally, we raise the question of which marker can serve as the last reporter of the residual viraemia, postulating that the absence of T-cell immune responses might be a more reliable marker than antibody decline after allo-HSCT. FUNDING: amfAR (American Foundation for AIDS Research; ARCHE Program), National Institutes of Health, National Institute of Allergy and Infectious Diseases, and Dutch Aidsfonds.

Characterization of Chronic Graft-versus-host Disease After Haploidentical Stem Cell Transplantation With Posttransplant Cyclophosphamide: A Study on Behalf of GETH-TC.

BACKGROUND: Chronic graft-versus-host disease (cGVHD) is a cause of late morbidity and nonrelapse mortality (NRM) after allogenic hematopoietic stem cell transplantation (allo-HSCT). Although studies evaluating haploidentical allo-HSCT (haplo-HSCT) using posttransplant cyclophosphamide (PTCy) demonstrate lower cGVHD rates, comprehensive data describing the clinical profile, risk factors, or outcomes of cGVHD within this platform are scarce. METHODS: We conducted a retrospective multicenter analysis of 389 consecutive patients who underwent haplo-HSCT PTCy in 7 transplant centers of the Spanish Group Grupo Español de Trasplante Hematopoyético y Terapia Celular (GETH-TC) between 2008 and 2020 describing incidence, clinical profile, risk factors, and cGVHD outcomes. RESULTS: Ninety-five patients of 389 developed cGVHD. Our data revealed that the incidence and severity of cGVHD are lower than those reported for HLA-identical transplantation with conventional prophylaxis and that the strongest predictor for cGVHD was previous acute GVHD ( P  = 0.031). Also, recipient age ≥60 y ( P  = 0.044) was protective against cGVHD. Moreover, patients with moderate cGVHD had longer event-free survival at 3 y than other patients ( P  = 0.016) and a lower relapse rate at 3 y ( P  = 0.036). CONCLUSIONS: Our results support the fact that the incidence and severity of cGVHD are lower than those reported for HLA-identical transplantation with conventional prophylaxis. In this series, patients who develop moderate cGVHD after haplo-HSCT PTCy had a higher overall survival and event-free survival, and lower relapse, suggesting higher graft-versus-leukemia effect. Although this is the largest series focused on characterizing cGVHD in haplo-HSCT PTCy, further prospective studies are needed to confirm the findings.

Digital PCR Improves Sensitivity and Quantification in Monitoring CAR-T Cells in B Cell Lymphoma Patients.

Chimeric antigen receptor T cells (CAR-T) has emerged as a promising therapy, over 60% of patients fail to sustain a long-term response. The underlying factors that leads to the effectiveness of this therapy are not completely understood, CAR-T cell persistence and monitoring seems to be pivotal for ensuring a successful response. Various monitoring methods such as multiparametric flow cytometry (MFC) or quantitative PCR (qPCR) have been applied. Our objective is to develop digital PCR (dPCR) assays for detection and quantification of CAR-T cells, comparing them with MFC and qPCR. Samples taken at different follow-up times from 45 patients treated with CAR-T therapy were analyzed to assess the correlation between the different methodologies. dPCR presented a high correlation with MFC and qPCR (r = 0.97 and r = 0.87, respectively), while offering a higher sensitivity (0.01%) compared to MFC (0.1%) and qPCR (1%). dPCR emerged as an alternative and highly sensitivity method for monitoring CAR-T cell dynamics. This technique is well-suited for implementation in clinical practice as a complementary technique to MFC.

Recent Bendamustine Treatment Before Apheresis Has a Negative Impact on Outcomes in Patients With Large B-Cell Lymphoma Receiving Chimeric Antigen Receptor T-Cell Therapy.

PURPOSE: Approximately 30%-40% of patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL) infused with CD19-targeted chimeric antigen receptor (CAR) T cells achieve durable responses. Consensus guidelines suggest avoiding bendamustine before apheresis, but specific data in this setting are lacking. We report distinct outcomes after CAR T-cell therapy according to previous bendamustine exposure. METHODS: The study included CAR T-cell recipients from seven European sites. Safety, efficacy, and CAR T-cell expansion kinetics were analyzed according to preapheresis bendamustine exposure. Additional studies on the impact of the washout period and bendamustine dose were performed. Inverse probability treatment weighting (IPTW) and propensity score matching (PSM) analyses were carried out for all efficacy comparisons between bendamustine-exposed and bendamustine-naïve patients. RESULTS: The study included 439 patients with R/R LBCL infused with CD19-targeted commercial CAR T cells, of whom 80 had received bendamustine before apheresis. Exposed patients had significantly lower CD3+ cells and platelets at apheresis. These patients had a lower overall response rate (ORR, 53% v 72%; P < .01), a shorter progression-free survival (PFS, 3.1 v 6.2 months; P = .04), and overall survival (OS, 10.3 v 23.5 months; P = .01) in comparison with the bendamustine-naïve group. Following adjustment methods for baseline variables, these differences were mitigated. Focusing on the impact of bendamustine washout before apheresis, those with recent (<9 months) exposure (N = 42) displayed a lower ORR (40% v 72%; P < .01), shorter PFS (1.3 v 6.2 months; P < .01), and OS (4.6 v 23.5 months; P < .01) in comparison with bendamustine-naïve patients. These differences remained significant after IPTW and PSM analysis. Conversely, the cumulative dose of bendamustine before apheresis did not affect CAR-T efficacy outcomes. CONCLUSION: Recent bendamustine exposure before apheresis was associated with negative treatment outcomes after CD19-targeted CAR T-cell therapy and should be therefore avoided in CAR T-cell candidates.

Impact of SCHOLAR-1 Criteria on Chimeric Antigen Receptor T Cell Therapy Efficacy in Aggressive B Lymphoma: A Real-World GELTAMO/GETH Study.

In the pre-chimeric antigen receptor T cell (CAR-T) therapy era, the SCHOLAR-1 study identified a group of patients with refractory aggressive B cell lymphoma (ABCL) with particularly poor prognoses. We recently published our real-world data from Spain, focused on this SCHOLAR-1 refractory group, and compared patients who underwent CAR-T therapy with the previous standard of care. In this study, we found that the efficacy of CAR-T therapy in refractory patients, in terms of progression-free survival (PFS) and overall survival (OS), was superior to that of the treatments available in the pre-CAR-T era. The main objective of these new analyses was to analyze treatment efficacy in terms of response rates and survival for patients with ABCL with or without the SCHOLAR-1 criteria. In addition, we analyzed the prognostic impact of each SCHOLAR-1 criterion independently. Our study aimed to assess the prognostic impact of SCHOLAR-1 criteria on ABCL patients treated with CAR-T therapy in Spain. This multicenter, retrospective, observational study. We included all adult patients treated with commercially available CAR-T cell products and diagnosed with ABCL different from primary mediastinal large B cell lymphoma between February 2019 and July 2022. Patients meeting any SCHOLAR-1 criteria (progressive disease as the best response to any line of therapy, stable disease as the best response to ≥4 cycles of first-line therapy or ≥2 cycles of later-line therapy, or relapse at <12 months after autologous stem cell transplantation [auto-SCT]) in the line of treatment before CAR-T therapy (SCHOLAR-1 group) were compared with those not meeting any of these criteria (non-SCHOLAR-1 group). To analyze the prognostic impact of individual SCHOLAR-1 criteria, all the patients who met any of the SCHOLAR-1 criteria at any time were included to assess whether these criteria have the same prognostic impact in the CAR-T era. In addition, patients were grouped according to whether they were refractory to the first line of treatment, refractory to the last line of treatment, or relapsed early after auto-SCT. The PFS and OS were calculated from the time of appearance of the SCHOLAR-1 refractoriness criteria. Of 329 patients treated with CAR-T (169 with axi-cel and 160 with tisa-cel), 52 were in the non-SCHOLAR-1 group and 277 were in the SCHOLAR-1 group. We found significantly better outcomes in the non-SCHOLAR-1 patients compared with the SCHOLAR-1 patients (median PFS of 12.2 and 3.3 months, respectively; P = .009). In addition, axi-cel showed better results in terms of efficacy than tisa-cel for both the non-SCHOLAR-1 group (hazard ratio [HR] for PFS, 2.7 [95% confidence interval (CI), 1.1 to 6.7; P = .028]; HR for OS, 7.1 [95% CI, 1.5 to 34.6; P = .015]) and SCHOLAR-1 group (HR for PFS, 1.8 [95% CI, 1.3 to 2.5; P < .001]; HR for OS, 1.8 [95% CI, 1.2 to 2.6; P = .002]), but also significantly more toxicity. Finally, separately analyzing the prognostic impact of each SCHOLAR-1 criterion revealed that refractoriness to the last line of treatment was the variable with the most significant impact on survival. In conclusion, SCHOLAR-1 refractoriness criteria notably influence the efficacy of CAR-T therapy. In our experience, axi-cel showed better efficacy than tisa-cel for both SCHOLAR-1 and non-SCHOLAR-1 patients. Refractoriness to the last line of treatment was the variable with the most significant impact on survival in the CAR-T therapy era.

Results of haploidentical transplant in patients with donor-specific antibodies: a survey on behalf of the Spanish Group of Hematopoietic Transplant and Cell Therapy.

Background: Donor-specific antibodies (DSAs) are IgG allo-antibodies against mismatched donor HLA molecules and can cause graft failure (GF) in the setting of haploidentical hematopoietic stem cell transplantation (haplo-HSCT). Our aim was to report the experience of the Spanish Group of Hematopoietic Transplant (GETH-TC) in DSA-positive patients who had undergone haplo-HSCT. Methods: We conducted a survey of patients who underwent haplo-HSCT in GETH-TC centers between 2012 and 2021. Data were collected on the DSA assay used, monitoring strategy, complement fixation, criteria for desensitization, desensitization strategies and transplant outcomes. Results: Fifteen centers from the GETH-TC responded to the survey. During the study period, 1,454 patients underwent haplo-HSCT. Seventy of the transplants were performed in 69 DSA-positive patients, all of whom lacked a suitable alternative donor; 61 (88%) patients were female (90% with prior pregnancies). All patients received post-transplant cyclophosphamide-based graft-versus-host disease prophylaxis. Regarding baseline DSA intensity, 46 (67%) patients presented mean fluorescence intensity (MFI) >5,000, including 21 (30%) with MFI >10,000 and three (4%) with MFI >20,000. Six patients did not receive desensitization treatment, four of them with MFI <5,000. Of 63 patients receiving desensitization treatment, 48 (76%) were tested after desensitization therapy, and a reduction in intensity was confirmed in 45 (71%). Three patients (5%) experienced an increase in MFI after desensitization, two of whom experienced primary GF. Cumulative incidence of neutrophil engraftment at day 28 was 74% in a median of 18 days (IQR, 15─20); six patients died before engraftment due to toxicity or infection and eight patients had primary GF despite desensitization in seven of them. After a median follow-up of 30 months, two-year overall and event-free survival were 46.5% and 39%, respectively. The two-year cumulative incidence of relapse was 16% and non-relapse mortality (NRM) was 43%. Infection was the most frequent cause of NRM, followed by endothelial toxicity. Multivariate analysis identified baseline MFI >20,000 as an independent risk factor for survival and an increase in titers after infusion as an independent risk factor for GF. Conclusions: Haplo-HSCT is feasible in DSA-positive patients, with high rates of engraftment after desensitization guided by DSA intensity. Baseline MFI >20,000 and increased intensity after infusion are risk factors for survival and GF.

Poor graft function after haploidentical stem cell transplantation with post-transplant cyclophosphamide.

This is a retrospective cohort study of consecutive adult patients who received a haploidentical-SCT (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) in a single centre. Poor graft function (PGF) was defined as the occurrence of either persistent neutropenia (ANC < 0.5 × 109/µL) with poor response to granulocyte colony-stimulating factors (G-CSF) and/or thrombocytopenia (platelets < 20 × 109/L) with transfusion dependence, with complete donor chimerism and without concurrent severe GVHD or underlying disease relapse, during the first 12 months after transplantation. Forty-four (27.5%) out of 161 patients were diagnosed with PGF. Previous CMV reactivation was significantly more frequent in patients with PGF (88.6% versus 73.5%, p = 0.04) and the number of reactivations was also higher in these patients. Besides, early CMV reactivations in the first 6 months post-SCT were also significantly more frequent among patients with PGF (88.6% versus 71.8% p = 0.025). Thirty-two percent of patients with PGF were treated with increasing doses of thrombopoietin-receptor agonists (TRA) and 7 patients were treated with a donor CD34 + selected boost. In total, 93.2% of patients reached adequate peripheral blood counts in a median time of 101 days (range 11-475) after diagnosis. PGF is a frequent complication after haplo-SCT with PT-Cy. CMV reactivation might be the most relevant factor associated to its development. Even when most patients recover peripheral counts with support therapy, there is a group of patients with persistent cytopenias who can effectively be treated with TRA and/or a boost of CD34 + selective cells.

Cell-Free DNA Dynamic Concentration and Other Variables Are Predictors of Early Progression after Chimeric Antigen Receptor T Cell Therapy in Patients with Diffuse Large B Cell Lymphoma.

We propose a novel biomarker that can identify patients at high risk of early progression after chimeric antigen receptor (CAR) T cell therapy. Calculation of cell-free DNA (cfDNA) with a pre-apheresis (PA) and pre-lymphodepletion (PL) sample allows monitoring of tumor dynamics (∆cfDNA). In the present study, ∆cfDNA and other biomarkers and clinical variables were evaluated in 58 patients with relapsed/refractory diffuse large B cell lymphoma (DLBCL). ∆cfDNA (>11 ng/mL plasma; P =.003), C-reactive protein (CRP) PL (>1.06 mg/dL; P = .004), lactate dehydrogenase (LDH) PL (>304; P = .006), disease status PL (progressive disease; P = .035) and sex (male; P = .016) were highly correlated with 1 month progression. After adjusting for ∆cfDNA, CRP PL, and LDH PL, disease status PL, and sex, ∆cfDNA remained associated with 1-month progression after CAR T cell infusion.

Role of allogeneic hematopoietic cell transplant for relapsed/refractory aggressive B-cell lymphomas in the CART era.

Anti-CD19 chimeric antigen receptor T cells (CART) has rapidly been adopted as the standard third-line therapy to treat aggressive B-cell lymphomas (ABCL) after failure of second-line therapy despite the lack of direct comparisons with allogeneic hematopoietic cell transplantation (alloHCT)-based strategies. Using the Grupo Español de Trasplante y Terapia Celular (GETH-TC) registry, we selected patients with the following characteristics: CART or alloHCT performed between 2016 and 2021; ≥18 years old; ABCL diagnosis; ≥2 lines of therapy; and either anti-CD19 CART or alloHCT as therapy at relapse. The analysis included a total of 316 (CART = 215, alloHCT = 101) patients. Median follow-up was 15 and 36 months for the CART and alloHCT cohorts, respectively. In the multivariate analysis, CART was confirmed to be similar to alloHCT for the primary study endpoint (progression-free survival) (hazard ratio [HR] 0.92, CI95%:0.56-1.51, p = 0.75). Furthermore, when the analysis was limited to only patients with chemo-sensitive diseases (complete and partial response) at infusion (CART = 26, alloHCT=93), no differences were reported (progression-free survival at month +18: 65% versus 55%, p = 0.59). However, CART had lower non-relapse mortality (HR 0.34, 95% CI: 0.13-0.85, p = 0.02). Given the lower toxicity and similar survival outcomes, these results suggest the use of CART before alloHCT.