Current trends and outcomes in cellular therapy activity in the United States, including prospective Patient Reported Outcomes data collection within the CIBMTR registry.

BACKGROUND: Center for International Blood and Marrow Transplant Research (CIBMTR) prepares an annual set of summary slides to detail the trends in transplantation and cellular therapies. For the first time in the 2023 summary slides, CIBMTR incorporates data for patients receiving chimeric antigen receptor T-cell (CAR-T) infusions. In addition, the data on patient-reported outcomes (PROs) is also included. OBJECTIVES: This report aims to update the annual trends in US HCT activity and incorporate data on the use of CAR-T therapies. Here we also aim to present and describe the development, implementation, and current status of the PRO data collection. STUDY DESIGN: In August 2020, CIBMTR launched the Protocol for Collection of Patient Reported Outcomes Data (CIBMTR PRO Protocol). The CIBMTR PRO Protocol operates under a centralized infrastructure to reduce burden to centers. Specifically, PRO data is collected from a prospective convenience sample of adult HCT and CAR-T patients who received treatment at contributing centers and consented for research. Data are merged and stored with the clinical data and used under the governance of the CIBMTR Research Database Protocol. Participants answer a series of surveys developed by the Patient Reported Outcomes Measurement Information System© (PROMIS) focusing on physical, social and emotional, and others measures assessing financial well-being, occupational functioning, and social determinants of health. To complement traditionally measured clinical outcomes, the surveys are administered at the same timepoints that clinical data is routinely collected. RESULTS: As of September 2023, PRO data from 993 patients across 25 different centers has been collected. With the goal of incorporating these important patient perspectives into standard clinical care, CIBMTR has added the PRO data to Data Back to Centers (DBtC). Through expanding the data types represented in the registry, CIBMTR aims to support holistic research accounting for the patient perspective in improving patient outcomes. CONCLUSION: PRO data at CIBMTR aims to provide the foundation for future large scale, population-level evaluations to determine areas for improvement, emerging disparities in access and health outcomes (eg, by age, race, and ethnicity), and new therapies that may impact current treatment guidelines. Continuing to collect and grow the PRO data is critical for understanding these changes and identifying methods for improving patient quality of life.

Bone Marrow Harvest: A White Paper of Best Practices by the NMDP Marrow Alliance.

Data on recent bone marrow harvest (BMH) collections from the NMDP has shown that bone marrow (BM) quality has decreased based on total nucleated cell count in the product. To ensure that quality BM products are available to all recipients, the NMDP Marrow Alliance was formed in April 2021 to increase the capability of BM collection centers to safely deliver high-quality products consistently and to identify and disseminate guidelines for performing BMH. This white paper describes the best practices for BMH as defined by the NMDP Marrow Alliance.

Long-term Outcomes of Peripheral Blood Stem Cell Unrelated Donors Mobilized with Filgrastim.

Allogeneic hematopoietic cell transplantation is a life-saving procedure used to treat of a variety of devastating diseases. It requires hematopoietic stem cells collected via filgrastim mobilized peripheral blood stem cells or bone marrow harvest from volunteer unrelated donors. There is a paucity of safety data regarding donors' long-term adverse events. This prospective, observational study combined peripheral blood stem cell donors enrolled on the NMDP Investigational New Drug trial and bone marrow donors between July 1, 1999, and September 30, 2015. The primary objective was to describe the long-term incidence of myeloid malignancies. Secondary objectives included describing the long-term incidence of lymphoid malignancies, non-hematologic malignancies, autoimmune disorders, and thrombotic events. 21643 donors (14530 peripheral blood stem cells and 7123 bone marrow) were included. The incidence rate of myeloid disorders per 100000 person years in donors of peripheral blood stem cells was 2.53 (95% CI: 0.82-7.84) and in donors of bone marrow it was 4.13 (95% CI: 1.33-12.8). The incidence rate ratio of peripheral blood stem cells /bone marrow donors was 0.61 (95% CI: 0.12-3.03; p=0.55). The incidence of other malignancies, autoimmunity, and thrombosis did not differ between donor types. This comprehensive study of long-term effects of filgrastim in unrelated donors of peripheral blood stem cells provides strong evidence that donors who receive filgrastim are not at increased risk of these events compared to bone marrow donors. It also provides reassurance to current donors undergoing stem cell mobilization as well as individuals considering joining stem cell registries such as NMDP.

Harmonizing definitions for hematopoietic recovery, graft rejection, graft failure, poor graft function, and donor chimerism in allogeneic hematopoietic cell transplantation: a report on behalf of the EBMT, ASTCT, CIBMTR, and APBMT.

Despite emergence of novel therapies to treat hematologic malignancies, allogeneic hematopoietic cell transplantation (allo-HCT) remains an essential treatment modality capable of curing these diseases. Allo-HCT has been also shown to be curative in benign hematologic disorders such as aplastic anemia, sickle cell disease, and thalassemia, among others. Recently, the American Society for Transplantation and Cellular Therapy (ASTCT) published standardized definitions for hematopoietic recovery, graft rejection, graft failure, poor graft function, and donor chimerism. To attempt broader international consensus, a panel of adult and pediatric physician transplant experts was assembled from European Society for Blood and Marrow Transplantation (EBMT), ASTCT, the Center for International Blood and Marrow Transplant Research (CIBMTR), and Asia-Pacific Blood and Marrow Transplantation (APBMT). Consensus was defined as ≥70% of voting members strongly agreeing or somewhat agreeing with a definition. With few exceptions, there was a consensus to endorse the prior ASTCT definitions. Importantly, we revised existing EBMT and CIBMTR data collection forms to align with these harmonized definitions that will facilitate research and international collaboration among transplant researchers and across transplant registries.

Donor-Derived Malignancy and Transplantation Morbidity: Risks of Patient and Donor Genetics in Allogeneic Hematopoietic Stem Cell Transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a key treatment option for hematologic malignancies (HMs), although it carries significant risks. Up to 30% of patients relapse after allo-HSCT, of which up to 2% to 5% are donor-derived malignancies (DDMs). DDMs can arise from a germline genetic predisposition allele or clonal hematopoiesis (CH) in the donor. Increasingly, genetic testing reveals that patient and donor genetic factors contribute to the development of DDM and other allo-HSCT complications. Deleterious germline variants in CEBPA, DDX41, GATA2, and RUNX1 predispose to inferior allo-HSCT outcomes. DDM has been linked to donor-acquired somatic CH variants in DNMT3A, ASXL1, JAK2, and IDH2, often with additional new variants. We do not yet have evidence to standardize donor genetic sequencing prior to allo-HSCT. The presence of hereditary HM disorders should be considered in patients with myeloid malignancies and their related donors, and screening of unrelated donors should include family and personal history of cytopenia and HMs. Excellent multidisciplinary care is critical to ensure efficient timelines for screening and necessary discussions among medical oncologists, genetic counselors, recipients, and potential donors. After allo-HSCT, HM relapse monitoring with genetic testing effectively results in genetic sequencing of the donor, as the transplanted hematopoietic system is donor-derived, which presents ethical challenges for disclosure to patients and donors. We encourage consideration of the recent National Marrow Donor Program policy that allows donors to opt-in for notification about detection of their genetic variants after allo-HSCT, with appropriate genetic counseling when feasible. We look forward to prospective investigation of the impact of germline and acquired somatic genetic variants on hematopoietic stem cell mobilization/engraftment, graft-versus-host disease, and DDM to facilitate improved outcomes through knowledge of genetic risk.

Tisagenlecleucel utilisation and outcomes across refractory, first relapse and multiply relapsed B-cell acute lymphoblastic leukemia: a retrospective analysis of real-world patterns.

Background: Tisagenlecleucel was approved by the Food and Drug Administration (FDA) in 2017 for refractory B-cell acute lymphoblastic leukemia (B-ALL) and B-ALL in ≥2nd relapse. Outcomes of patients receiving commercial tisagenlecleucel upon 1st relapse have yet to be established. We aimed to report real-world tisagenlecleucel utilisation patterns and outcomes across indications, specifically including patients treated in 1st relapse, an indication omitted from formal FDA approval. Methods: We conducted a retrospective analysis of real-world tisagenlecleucel utilisation patterns across 185 children and young adults treated between August 30, 2017 and March 6, 2020 from centres participating in the Pediatric Real-World CAR Consortium (PRWCC), within the United States. We described definitions of refractory B-ALL used in the real-world setting and categorised patients by reported Chimeric Antigen Receptor (CAR) T-cell indication, including refractory, 1st relapse and ≥2nd relapse B-ALL. We analysed baseline patient characteristics and post-tisagenlecleucel outcomes across defined cohorts. Findings: Thirty-six percent (n = 67) of our cohort received tisagenlecleucel following 1st relapse. Of 66 evaluable patients, 56 (85%, 95% CI 74-92%) achieved morphologic complete response. Overall-survival (OS) and event-free survival (EFS) at 1-year were 69%, (95% CI 58-82%) and 49%, (95% CI 37-64%), respectively, with survival outcomes statistically comparable to remaining patients (OS; p = 0.14, EFS; p = 0.39). Notably, toxicity was increased in this cohort, warranting further study. Interestingly, of 30 patients treated for upfront refractory disease, 23 (77%, 95% CI 58-90%) had flow cytometry and/or next-generation sequencing (NGS) minimum residual disease (MRD)-only disease at the end of induction, not meeting the historic morphologic definition of refractory. Interpretation: Our findings suggested that tisagenlecleucel response and survival rates overlap across patients treated with upfront refractory B-ALL, B-ALL ≥2nd relapse and B-ALL in 1st relapse. We additionally highlighted that definitions of refractory B-ALL are evolving beyond morphologic measures of residual disease. Funding: St. Baldrick's/Stand Up 2 Cancer, Parker Institute for Cancer Immunotherapy, Virginia and D.K. Ludwig Fund for Cancer Research.

The effect of increased collect pump rate on collection efficiency in hematopoietic progenitor cell collection by apheresis in allogeneic adult donors-A single center analysis.

BACKGROUND: Optimizing CD34 recovery while minimizing harm to hematopoietic progenitor cell donors by apheresis (HPC(A) donors) is critical to the success of allogeneic hematopoietic cell transplantation. We examined the efficacy and safety of starting allogeneic HPC(A) donors at a collect pump rate (CPR) of 2 mL/min on the Spectra Optia regardless of the inlet flow rate and/or pre-apheresis white blood cell (WBC) count (high CPR group). STUDY DESIGN AND METHODS: A single-center retrospective study was performed on allogeneic adult donors from 10/2020 to 12/2022. From 10/2020 to 6/19/2022, all donors had CPR of ~1 mL/min (historical group). High CPR group started 6/20/2022. RESULTS: During the study period, 412 donors were in historical group versus 196 (32.2%) in high CPR group. Median CD34 collection efficiency (CE) was higher and more consistent in high CPR group (55.1% vs. 53% in historical group, p < .0001) and remained significant in multivariate analysis. Although product volume was higher in high CPR group, WBC, hematocrit, and platelet concentrations were significantly lower. No difference in engraftment outcomes in patients receiving products from two groups was observed. Moreover, no differences occurred in a significant peri-procedural adverse event or percent decrease in platelets (6.87% decrease in platelets per 100 × 106 CD34 cells collected versus 6.66% in historical group, p = .89). Furthermore, high CPR group had ~26 min less in collection time for every 100 × 106 CD34 cells collected, resulting in less positive fluid balances. CONCLUSIONS: Starting allogeneic HPC(A) donor collection at a CPR of 2 mL/min is safe and effective.

Clinical impact of cryopreservation of allogeneic hematopoietic cell grafts during the onset of the COVID-19 pandemic.

At the onset of the COVID-19 pandemic, the National Marrow Donor Program mandated the cryopreservation of hematopoietic cell grafts from volunteer unrelated donors because of numerous patient and donor safety concerns and logistical hurdles. Using the Center for International Blood and Marrow Transplant Research outcomes database, we report the impact of cryopreservation on overall survival (OS) and other outcomes within 1 year after hematopoietic cell transplantation (HCT). We analyzed 1543 recipients of cryopreserved allografts receiving HCT at US centers during the first 6 months of the pandemic and compared them with 2499 recipients of fresh allografts during a 6-month period in 2019. On multivariable regression analysis, we observed no difference in the OS (P = .09), nonrelapse mortality (P = .89), graft-versus-host disease (GVHD), or GVHD- and relapse-free survival (P = .58) in recipients of cryopreserved vs fresh allografts. Disease-free survival (DFS) was lower in the cryopreserved allograft recipients (P = .006) because of a higher risk of relapse (P = .01) compared with the fresh allograft recipients. Primary graft failure was higher (P = .01), and the risk of chronic GVHD was lower (P = .001) with cryopreservation compared with fresh grafts. In conclusion, although there was no negative impact of cryopreservation on OS, relapse was higher, and DFS was lower than that with no cryopreservation. Fresh grafts are recommended as the pandemic-related logistical hurdles resolve. Cryopreservation should be considered an option for patients when fresh grafts are not feasible.

HLH-like toxicities predict poor survival after the use of tisagenlecleucel in children and young adults with B-ALL.

Chimeric antigen receptor-associated hemophagocytic lymphohistiocytosis (HLH)-like toxicities (LTs) involving hyperferritinemia, multiorgan dysfunction, coagulopathy, and/or hemophagocytosis are described as occurring in a subset of patients with cytokine release syndrome (CRS). Case series report poor outcomes for those with B-cell acute lymphoblastic leukemia (B-ALL) who develop HLH-LTs, although larger outcomes analyses of children and young adults (CAYAs) with B-ALL who develop these toxicities after the administration of commercially available tisagenlecleucel are not described. Using a multi-institutional database of 185 CAYAs with B-ALL, we conducted a retrospective cohort study including groups that developed HLH-LTs, high-grade (HG) CRS without HLH-LTs, or no to low-grade (NLG) CRS without HLH-LTs. Primary objectives included characterizing the incidence, outcomes, and preinfusion factors associated with HLH-LTs. Among 185 CAYAs infused with tisagenlecleucel, 26 (14.1%) met the criteria for HLH-LTs. One-year overall survival and relapse-free survival were 25.7% and 4.7%, respectively, in those with HLH-LTs compared with 80.1% and 57.6%, respectively, in those without. In multivariable analysis for death, meeting criteria for HLH-LTs carried a hazard ratio of 4.61 (95% confidence interval, 2.41-8.83), controlling for disease burden, age, and sex. Patients who developed HLH-LTs had higher pretisagenlecleucel disease burden, ferritin, and C-reactive protein levels and lower platelet and absolute neutrophil counts than patients with HG- or NLG-CRS without HLH-LTs. Overall, CAYAs with B-ALL who developed HLH-LTs after tisagenlecleucel experienced high rates of relapse and nonrelapse mortality, indicating the urgent need for further investigations into prevention and optimal management of patients who develop HLH-LTs after tisagenlecleucel.

Real-World Data Showing Trends and Outcomes by Race and Ethnicity in Allogeneic Hematopoietic Cell Transplantation: A Report from the Center for International Blood and Marrow Transplant Research.

The use of HLA-mismatched donors could enable more patients with ethnically diverse backgrounds to receive allogeneic hematopoietic cell transplantation (HCT) in the United States. However, real-world trends and outcomes following mismatched donor HCT for diverse patients remain largely undefined. We conducted this study to determine whether the use of mismatched donor platforms have increased the access to allogeneic HCT for ethnically diverse patients, particularly through the application of novel graft-versus-host disease (GVHD) prophylaxis regimens, and whether outcomes for diverse patients are comparable to those of non-Hispanic White patients. This observational cross-sectional study used real-world data from the Center for International Blood and Marrow Transplant Research (CIBMTR) registry. All patients receiving their first allogeneic HCT in the United States between 2009 and 2020 were included, with a focus on transplantations performed in 2020. Data from patients undergoing allogeneic HCT using bone marrow, peripheral blood, or cord blood from HLA-matched or mismatched related and unrelated donors were analyzed. Specifically, relative proportion of allogeneic HCT was generated as percentage of total for donor type and for patient age, disease indication, GVHD prophylaxis, and race and ethnicity. Causes of death were summarized using frequencies, and the Kaplan-Meier estimator was used for estimating overall survival. Compared to matched related donor and matched unrelated donor HCT, more ethnically diverse patients received mismatched unrelated donor, haploidentical donor, and cord blood HCT. Although matched unrelated donor remains the most common donor type, the use of haploidentical donors has increased significantly over the last 5 years. Paralleling this increase in haploidentical HCT is the increased use of post-transplantation cyclophosphamide (PTCy) as GVHD prophylaxis. Relative to previous transplantation eras, the most contemporary era is associated with the highest survival rates following allogeneic HCT irrespective of patient race and ethnicity. Nonetheless, disease relapse remains the primary cause of death for both adult and pediatric allogeneic HCT recipients by donor type and across all patient racial/ethnic groups. Ethnically diverse patients are undergoing allogeneic HCT at higher rates, largely through the use of alternative donor platforms incorporating PTCy. Maintaining access to potential life-saving allogeneic HCT using alternative donors and novel GVHD prophylaxis strategies and improving HCT outcomes, particularly disease relapse, remain urgent clinical needs.

Evaluation of Children with Malignancies for Blood and Marrow Transplantation: A Report from the ASTCT Committee on Practice Guidelines.

Evaluation of a candidate for hematopoietic cell transplantation (HCT) is a complex process with substantial intercenter variability. Although literature providing guidance for evaluating the eligibility of adults is well established, similar guidance for children is lacking. To address gaps between adult recommendations and the specific needs of children, we convened a panel of pediatric HCT experts from a wide geographic range of American Society of Transplantation and Cellular Therapy (ASTCT) member institutions to offer recommendations for pediatric-focused pre-HCT evaluation. In this report from the ASTCT Committee on Practice Guidelines, we present a practical framework for evaluating children with malignancies who are candidates for HCT. We also highlight key differences from adults and emphasize areas of unmet need that require additional research to delineate best practices.

A Multicenter Phase 2 Clinical Trial of 10-Day Decitabine, Dose-Escalated Donor Lymphocyte Infusion, and Ruxolitinib for Relapsed Acute Myeloid Leukemia and Myelodysplastic Syndromes after Allogeneic Hematopoietic Cell Transplantation.

Post-transplantation relapse of acute myeloid leukemia and myelodysplastic syndromes has a poor prognosis. Donor lymphocyte infusion (DLI) is one treatment approach. However, efficacy is limited, and toxicity, mostly in the form of acute graft-versus-host disease (GVHD), is frequent. We tested a novel approach using 10-day decitabine, dose-escalated DLI, and ruxolitinib in a multicenter phase 2 trial aimed at increasing the efficacy of DLI and reducing its toxicity. Up to four 28-day cycles were administered. The primary endpoint was 6-month overall survival (OS). Of the 14 patients who started cycle 1, 13 received 1 DLI, 6 received 2 DLIs, and 1 received 3 4 DLIs. A preplanned interim analysis after enrolling 14 patients suggested futility, and the trial was closed to accrual. The final analysis showed a 6-month OS of 36% (95% confidence interval [CI], 18 to 72), a 1-year progression-free survival of 7% (95% CI, 1% to 47%), a 6-month cumulative incidence of grade II-IV acute GVHD of 57% (95% CI, 26% to 80%), and a 1-year nonrelapse mortality of 14% (95% CI, 2% to 38%). The combined modality treatment studied in this trial was ineffective and did not reduce DLI toxicity.

Association of ABO mismatch with the outcomes of allogeneic hematopoietic cell transplantation for acute leukemia.

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment for acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). While many factors influence the outcomes of allo-HCT, the independent impact of donor-recipient ABO mismatching remains unclear. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we identified patients aged ≥18 years with AML or ALL who underwent allo-HCT between 2008 and 2018. Our objectives were to analyze the outcomes of allo-HCT based on the donor-recipient ABO status (match, minor mismatch, major mismatch, bidirectional mismatch). Among 4946 eligible patients, 2741 patients (55.4%) were ABO matched, 1030 patients (20.8%) had a minor ABO mismatch, 899 patients (18.1%) had a major ABO mismatch, and 276 patients (5.6%) had a bidirectional ABO mismatch. In multivariable analyses, compared to ABO matched allo-HCT, the presence of a major ABO mismatch was associated with worse overall survival (HR 1.16, 95% CI 1.05-1.29; p = 0.005), inferior platelet engraftment (HR 0.83, 95% CI 0.77-0.90; p < 0.001), and higher primary graft failure (HR 1.60, 95% CI 1.12-2.30, p = 0.01). Relapse, acute graft versus host disease (GVHD) grades III-IV and chronic GVHD were not significantly associated with ABO status. While donor age was not significantly associated with outcomes, older recipient age was associated with worse survival and non-relapse mortality. Our study demonstrates that donor-recipient ABO status is independently associated with survival and other post-transplantation outcomes in acute leukemia. This underscores the importance of considering the ABO status in donor selection algorithms and its impact in acute leukemia.

Three-Year Update of Tisagenlecleucel in Pediatric and Young Adult Patients With Relapsed/Refractory Acute Lymphoblastic Leukemia in the ELIANA Trial.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.In the primary analysis of the global phase II ELIANA trial (ClinicalTrials.gov identifier: NCT02435849), tisagenlecleucel provided an overall remission rate of 81% in pediatric and young adult patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL), with 59% of responders remaining relapse-free at 12 months. Here, we report an update on efficacy, safety, and patient-reported quality of life in 79 pediatric and young adult patients with R/R B-ALL following a median follow-up of 38.8 months. The overall remission rate was 82%. The median event-free survival was 24 months, and the median overall survival was not reached. Event-free survival was 44% (95% CI, 31 to 57) and overall survival was 63% (95% CI, 51 to 73) at 3 years overall (most events occur within the first 2 years). The estimated 3-year relapse-free survival with and without censoring for subsequent therapy was 52% (95% CI, 37 to 66) and 48% (95% CI, 34 to 60), respectively. No new or unexpected long-term adverse events were reported. Grade 3/4 adverse events were reported in 29% of patients > 1 year after infusion; grade 3/4 infection rate did not increase > 1 year after infusion. Patients reported improvements in quality of life up to 36 months after infusion. These findings demonstrate favorable long-term safety and suggest tisagenlecleucel as a curative treatment option for heavily pretreated pediatric and young adult patients with R/R B-ALL.

Outcomes After Nonresponse and Relapse Post-Tisagenlecleucel in Children, Adolescents, and Young Adults With B-Cell Acute Lymphoblastic Leukemia.

PURPOSE: Nonresponse and relapse after CD19-chimeric antigen receptor (CAR) T-cell therapy continue to challenge survival outcomes. Phase II landmark data from the ELIANA trial demonstrated nonresponse and relapse rates of 14.5% and 28%, respectively, whereas use in the real-world setting showed nonresponse and relapse rates of 15% and 37%. Outcome analyses describing fate after post-CAR nonresponse and relapse remain limited. Here, we aim to establish survival outcomes after nonresponse and both CD19+ and CD19- relapses and explore treatment variables associated with inferior survival. METHODS: We conducted a retrospective multi-institutional study of 80 children and young adults with B-cell acute lymphoblastic leukemia experiencing nonresponse (n = 23) or relapse (n = 57) after tisagenlecleucel. We analyze associations between baseline characteristics and these outcomes and establish survival rates and salvage approaches. RESULTS: The overall survival (OS) at 12 months was 19% across nonresponders (n = 23; 95% CI, 7 to 50). Ninety-five percent of patients with nonresponse had high preinfusion disease burden. Among 156 morphologic responders, the cumulative incidence of relapse was 37% (95% CI, 30 to 47) at 12 months (CD19+; 21% [15 to 29], CD19-; 16% [11 to 24], median follow-up; 380 days). Across 57 patients experiencing relapse, the OS was 52% (95% CI, 38 to 71) at 12 months after time of relapse. Notably, CD19- relapse was associated with significantly decreased OS as compared with patients who relapsed with conserved CD19 expression (CD19- 12-month OS; 30% [14 to 66], CD19+ 12-month OS; 68% [49 to 92], P = .0068). Inotuzumab, CAR reinfusion, and chemotherapy were used as postrelapse salvage therapy with greatest frequency, yet high variability in treatment sequencing and responses limits efficacy analysis across salvage approaches. CONCLUSION: We describe poor survival across patients experiencing nonresponse to tisagenlecleucel. In the post-tisagenlecleucel relapse setting, patients can be salvaged; however, CD19- relapse is distinctly associated with decreased survival outcomes.

Higher doses of tisagenlecleucel are associated with improved outcomes: a report from the pediatric real-world CAR consortium.

Remarkable complete response rates have been shown with tisagenlecleucel, a chimeric antigen receptor (CAR) T-cell therapy targeting CD19, in patients up to age 26 years with refractory/relapsed B-cell acute lymphoblastic leukemia; it is US Food and Drug Administration approved for this indication. Currently, patients receive a single dose of tisagenlecleucel across a wide dose range of 0.2 to 5.0 × 106 and 0.1 to 2.5 × 108 CAR T cells per kg for patients ≤50 and >50 kg, respectively. The effect of cell dose on survival and remission is not yet well established. Our primary goal was to determine if CAR T-cell dose affects overall survival (OS), event-free survival (EFS), or relapse-free-survival (RFS) in tisagenlecleucel recipients. Retrospective data were collected from Pediatric Real World CAR Consortium member institutions and included 185 patients infused with commercial tisagenlecleucel. The median dose of viable transduced CAR T cells was 1.7 × 106 CAR T cells per kg. To assess the impact of cell dose, we divided responders into dose quartiles: 0.134 to 1.300 × 106 (n = 48 [27%]), 1.301 to 1.700 × 106 (n = 46 [26%]), 1.701 to 2.400 × 106 (n = 43 [24%]), and 2.401 to 5.100 × 106 (n = 43 [24%]). OS, EFS, and RFS were improved in patients who received higher doses of tisagenlecleucel (P = .031, .0079, and .0045, respectively). Higher doses of tisagenlecleucel were not associated with increased toxicity. Because the current tisagenlecleucel package insert dose range remains broad, this work has implications in regard to targeting higher cell doses, within the approved dose range, to optimize patients' potential for long-standing remission.

Neither COVID-19, nor cryopreservation, prevented allogeneic product infusion: A report from the National Marrow Donor Program.

Background: The Coronavirus Disease 2019 (COVID-19) pandemic in early 2020 has resulted in an unprecedented level of uncertainty and challenge for the stem cell donor registries. To address these challenges, rapid strategies were implemented by the National Marrow Donor Registry (NMDP) and its network partners. Herein, we aim to report the impact of the COVID-19 pandemic on the collection, utilization of grafts, and short-term outcomes of patients who received stem cell products from COVID-19-positive donors. Methods: NMDP data during the early phase (1 March 2020 through 1 May 2020) of the pandemic were compared to the later phase (1 March 2021 through 1 May 2021). Odds ratios were calculated to determine the impact of the pandemic on graft sources requested by transplant centers (TCs). The Kruskal-Wallis test was used to test the effect of the pandemic on the disease indication, volume of searches, and number of products not infused. Results: Although there was an initial decline in overall donor searches during the early phase of the pandemic, these numbers increased reaching pre-pandemic levels during the later phase. Urgent malignant diseases remained the most common indication for transplant in 2021. The pandemic necessitated cryopreservation of stem cell products due to transportation restrictions as well as clinical uncertainties in managing the virus. Cryopreserved grafts remained the most common requested grafts throughout the pandemic. In the later phase of the pandemic, the total numbers of requests for fresh grafts increased, mostly due to the increase in requests for fresh bone marrow (BM) grafts. As the pandemic continued, TCs became more accepting of cryopreservation, resulting in a reduction in the number of products not infused. Lastly, no short-term deleterious outcomes were noted among the patients who had stem cell products infused from a SARS-CoV-2-positive donor. Conclusion: Throughout the pandemic, the NMDP and TCs worked tirelessly to ensure that patients would receive lifesaving grafts when needed. The data reported here, although limited by small numbers, illustrate that transplantation from donors with COVID-19 is feasible and safe.

Suitability of haematopoietic cell donors: updated consensus recommendations from the WBMT standing committee on donor issues.

The contribution of related donors to the globally rising number of allogeneic haematopoietic stem cell transplantations (HSCT) remains increasingly important, particularly because of the growing use of haploidentical HSCT. Compared with the strict recommendations on the suitability for unrelated donors, criteria for related donors allow for more discretion and vary between centres. In 2015, the donor outcome committee of the Worldwide Network for Blood and Marrow Transplantation (WBMT) proposed consensus recommendations of suitability criteria for paediatric and adult related donors. This Review provides updates and additions to these recommendations from a panel of experts with global representation, including the WBMT, the European Society for Blood and Marrow Transplantation donor outcome committee, the Center for International Blood and Marrow Transplant Research donor health and safety committee, the US National Marrow Donor Program, and the World Marrow Donor Association, after review of the current literature and guidelines. Sections on the suitability of related donors who would not qualify as unrelated donors have been updated. Sections on communicable diseases, clonal haematopoiesis of indeterminate potential, paediatric aspects including psychological issues, and reporting on serious adverse events have been added. The intention of this Review is to support decision making, with the goal of minimising the medical risk to the donor and protecting the recipient from transmissible diseases.