Over the last 15 years activity of diagnostic flow cytometry services have evolved from monitoring of CD4 T cell subsets in HIV-1 infection to screening for primary and secondary immune deficiencies syndromes and assessment of immune constitution following B cell depleting therapy and transplantation. Changes in laboratory activity in high income countries have been driven by initiation of anti-retroviral therapy (ART) in HIV-1 regardless of CD4 T cell counts, increasing recognition of primary immune deficiency syndromes and the wider application of B cell depleting therapy and transplantation in clinical practice. Laboratories should use their experience in standardization and quality assurance of CD4 T cell counting in HIV-1 infection to provide immune monitoring services to patients with primary and secondary immune deficiencies. Assessment of immune reconstitution post B cell depleting agents and transplantation can also draw on the expertise acquired by flow cytometry laboratories for detection of CD34 stem cell and assessment of MRD in hematological malignancies. This guideline provides recommendations for clinical laboratories on providing flow cytometry services in screening for immune deficiencies and its emerging role immune reconstitution after B cell targeting therapies and transplantation.

Background/Objectives: Relapsed B-cell acute lymphoblastic leukemia (B-ALL) remains an unresolved matter of concern regarding adverse outcomes. This case study aimed to evaluate the effectiveness of blinatumomab, with or without door lymphocyte infusion (DLI), in treating measurable residual disease (MRD)-positive B-ALL. Methods: All patients who received blinatumomab salvage therapy were included in this study. Eleven patients were included in the study. All patients were evaluated for MRD-negativity. Results: Before starting blinatumomab therapy, seven patients tested positive for MRD, three tested negative, and one had refractory disease. Hematopoietic cell transplantation (HCT) was reserved for five patients with persistent MRD. Six patients became MRD-negative and subsequent HCT was not performed. Only two patients relapsed; one patient died of relapse, and the other one received carfilzomib-based therapy and was MRD-negative thereafter. Nine patients were MRD-negative at a median follow-up of 28 months (15-52 months). Two of three MRD-positive post-transplant patients remained in complete molecular remission after preemptive DLI at the last follow-up date. In the first salvage, blinatumomab may achieve complete remission and bridging to HCT in pediatric patients with end-of-induction MRD-positive B-cell precursor ALL. Conclusions: The decision on how to treat post-transplant relapse continues to affect survival outcomes. Blinatumomab combined with DLI may extend the armamentarium of release options for high-risk pediatric patients. This approach is encouraging for high-risk ALL patients who are MRD-positive post-transplantation.

On behalf of Cell Therapy Transplant Canada (CTTC), we are pleased to present the Abstracts of the CTTC 2023 Annual Conference. The conference was held in-person, 31 May-2 June 2023, in Halifax, Nova Scotia at the Westin Nova Scotian hotel. Poster authors presented their work during a lively and engaging welcome reception on Thursday, 1 June, and oral abstract authors were featured during the oral abstract session in the afternoon of Friday, 2 June 2023. Twenty-three (23) abstracts were selected for presentation as posters and four (4) as oral presentations. Abstracts were submitted within four categories: (1) Basic/Translational Sciences, (2) Clinical Trials/Observations, (3) Laboratory/Quality, and (4) Pharmacy/Nursing/Other Transplant Support. The top four (4) oral abstracts and top four (4) poster abstracts were selected to receive an award. All of these were marked as \"Award Recipient\" within the relevant category. We congratulate all the presenters on their research and contributions to the field.

BACKGROUND: Hematopoietic cell transplantation (HCT) is a highly invasive and life-threatening treatment for hematological neoplasms and some types of cancer that can challenge the patient\'s meaning structures. Restoring meaning (i.e., building more flexible and significant explanations of the disease and treatment burden) can be aided by strengthening psychological flexibility by means of an Acceptance and Commitment Therapy (ACT) intervention. Thus, this trial aims to examine the effect of the ACT intervention on the meaning-making process and the underlying mechanisms of change in patients following HCT compared to a minimally enhanced usual care (mEUC) control group. The trial will be enhanced with a single-case experimental design (SCED), where ACT interventions will be compared between individuals with various pre-intervention intervals.
METHODS: In total, 192 patients who qualify for the first autologous or allogeneic HCT will be recruited for a two-armed parallel randomized controlled trial comparing an online self-help 14-day ACT training to education sessions (recommendations following HCT). In both conditions, participants will receive once a day a short survey and intervention proposal (about 5-10 min a day) in the outpatient period. Double-blinded assessment will be conducted at baseline, during the intervention, immediately, 1 month, and 3 months after the intervention. In addition, 6-9 participants will be invited to SCED and randomly assigned to pre-intervention measurement length (1-3 weeks) before completing ACT intervention, followed by 7-day observations at the 2nd and 3rd post-intervention measure. The primary outcome is meaning-related distress. Secondary outcomes include psychological flexibility, meaning-making coping, meanings made, and well-being as well as global and situational meaning.
CONCLUSIONS: This trial represents the first study that integrates the ACT and meaning-making frameworks to reduce meaning-related distress, stimulate the meaning-making process, and enhance the well-being of HCT recipients. Testing of an intervention to address existential concerns unique to patients undergoing HCT will be reinforced by a statistically rigorous idiographic approach to see what works for whom and when. Since access to interventions in the HCT population is limited, the web-based ACT self-help program could potentially fill this gap.
BACKGROUND: ClinicalTrials.gov ID: NCT06266182. Registered on February 20, 2024.

UNASSIGNED: Cytomegalovirus (CMV) infection remains the most common clinically significant infection after allogeneic hematopoietic stem cell transplantation (allo-HCT) and is associated with considerable morbidity and mortality.
UNASSIGNED: The present study was designed to describe and compare the incidence of untreated CMV reactivation (uCMVr), clinically significant infection (cs-CMVi) and disease (CMVd), as well as CMV-related hospitalization and outcome of allo-HCT patients, either treated with letermovir (LET) primary prophylaxis or managed with preemptive therapy (PET).
UNASSIGNED: This is a prospective observational cohort study of adult CMV seropositive allo-HCT patients who either received primary prophylaxis with LET within the first 100 days after HCT or were managed with PET.
UNASSIGNED: The study population comprised 105 patients (28 in the LET group and 77 in the PET group). Compared to the PET group, patients in the LET group received more allo-HCT from alternative donors (54.5% vs. 82.14%, P=0.012). More than half of the patients in both groups were classified as high risk for CMVd. In the LET vs. PET group, cs-CMVi and CMVd developed respectively in 0 vs. 50 (64.94%), P=<0.0001, and 0 vs. 6 (7.79%), P=0.18. In the LET group, uCMVr occurred in 5 (17.8%) and were all considered blips. Hospital admissions related to cs-CMVi or CMVd in the PET group vs. LET group were 47 (61.04%) vs. 0, respectively, P=<0.0001. No differences were observed in 100-day mortality.
UNASSIGNED: LET primary prophylaxis proved effective in preventing cs-CMVi and CMVd and reducing hospitalizations in allo-HCT adults. Blips can occur during prophylaxis and do not require LET discontinuation.

Since 1980\'s, the established/standard treatment of acute myeloid leukemia (AML) is cytarabine infusion with anthracycline (7 + 3 regimen). We compared the 7 + 3 regimen in older secondary/high-risk AML patientsfrom a clinical trial with a matched population from the Swedish AML Registrytreated withan increased cytarabine dose in induction and consolidation as recommended in the Swedish National Guidelines since 2005. After successfulpropensity score matching, 104 patients per group were included. The primary outcome was overall survival (OS), and standard dosed patients had a median OS of 6.4 versus 10.7 months with increased dose intensity (hazard ratio:0.69, p = 0.012), with 5-year OS of 8.7% and 18.1%, andremission rates of 36% and 60%, respectively (p < 0.001). Median OS after allogeneic hematopoietic cell transplantation (in 27.9% per group) was 10.4 and 20.7 months, respectively. We conclude that the more intensive cytarabine schedule seems to provide improved outcomes inthe investigated AML patient group.

Frailty is a phenotype of decreased physiologic reserve associated with increased risk of toxicities and nonrelapse mortality (NRM) in hematopoietic cell transplant (HCT) recipients. The incidence, predictors, and adverse effects of pre-HCT frailty are not well known. We evaluated the association of pre-HCT frailty, defined using Fried\'s criteria, with age and baseline characteristics in patients ≥18 years undergoing autologous (auto) or allogeneic (allo) HCT for hematological malignancies. Assessments were performed as part of routine pre-HCT evaluations and then retrospectively analyzed. We additionally investigated the association of mental health distress indicators with frailty and the association between frailty and transplant outcomes including NRM and overall survival (OS) plus healthcare utilization. Patients undergoing HCT for hematological malignancies were analyzed (total n = 300; 162 auto, 138 allo). The overall prevalence of frailty was 18%, 21.7% among alloHCT, and 14.8% among autoHCT recipients, with similar distributions of frailty domains. Logistic regression analysis of the overall cohort revealed that older age was associated with an increased risk of frailty (odds ratio [OR] 1.37, 95% confidence interval [CI] [1.02-1.82]; P = 0.04). AlloHCT (OR 2.03, CI [1.07-3.84]; P = .03), and patient health questionnaire-9 (PHQ-9) (health depression) score ≥10 (OR 6.28, CI 1.93-20.43; P < .01) were each independently associated with pre-HCT frailty. In alloHCT patients, older age (OR 1.44, CI [1.00-2.06]; P = .05) was the only significant risk factor for pre-HCT frailty, while for autoHCT patients, only a higher PHQ-9 score was associated with frailty (OR 6.43, CI [1.34-30.82]; P = .02). For the whole cohort OS at 1 year was lower in frail recipients at 83% (95% CI, 70-91%) versus 92% (95% CI, 88-95%) in nonfrail (P = .04); with multivariate analysis showing higher risk of death in the frail group (hazard ratio [HR] 2.31, CI 0.97-5.46; P = .06). In the alloHCT cohort, multivariate analysis showed greater 1-year mortality in frail recipients (HR 2.55, CI [0.99-6.56]; P = .053). In the alloHCT recipients, we observed a 1-year NRM of 20% in frail patients versus 9% in nonfrail, and multivariate analysis showed a marginally higher risk of NRM in the frail group (HR 2.70, CI 0.90-8.10; P = .08). Frailty was not associated with higher risk of relapse in alloHCT or autoHCT recipients. Frail alloHCT patients experienced a longer initial hospital stay following HCT compared to nonfrail recipients (P < .01). We observed a high prevalence of pre-HCT frailty across all age groups, and identify older age is a risk factor for frailty, particularly in alloHCT recipients. Frailty is associated with a greater risk of NRM and lower survival which needs investigation in a larger cohort. Frailty associates with greater HCT complexity suggesting a need for early assessments and targeted interventions for this vulnerable population. Our findings suggest the utility of frailty and mental distress screening along with multidisciplinary interventions in pre-HCT to limit the morbidity of HCT.

BACKGROUND: Patients with hematological malignancies receiving hematopoietic cell transplantation (HCT) or chimeric antigen receptor (CAR) T-cell therapy are at risk of developing serious clinical complications after discharge.
OBJECTIVE: The aim of the TEL-HEMATO study was to improve our telehealth platform for the follow-up of patients undergoing HCT or CAR T-cell therapy during the first 3 months after discharge with the addition of wearable devices.
METHODS: Eleven patients who received autologous (n=2) or allogeneic (n=5) HCT or CAR T-cell therapy (n=4) for hematological malignancies were screened from November 2022 to July 2023. Two patients discontinued the study after enrollment. The telehealth platform consisted of the daily collection of vital signs, physical symptoms, and quality of life assessment up to 3 months after hospital discharge. Each patient received a clinically validated smartwatch (ScanWatch) and a digital thermometer, and a dedicated smartphone app was used to collect these data. Daily revision of the data was performed through a web-based platform by a hematologist or a nurse specialized in HCT and CAR T-cell therapy.
RESULTS: Vital signs measured through ScanWatch were successfully collected with medium/high adherence: heart rate was recorded in 8/9 (89%) patients, oxygen saturation and daily steps were recorded in 9/9 (100%) patients, and sleeping hours were recorded in 7/9 (78%) patients. However, temperature recorded manually by the patients was associated with lower compliance, which was recorded in 5/9 (55%) patients. Overall, 5/9 (55%) patients reported clinical symptoms in the app. Quality of life assessment was completed by 8/9 (89%) patients at study enrollment, which decreased to 3/9 (33%) at the end of the third month. Usability was considered acceptable through ratings provided on the System Usability Scale. However, technological issues were reported by the patients.
CONCLUSIONS: While the addition of wearable devices to a telehealth clinical platform could have potentially synergic benefits for HCT and CAR T-cell therapy patient monitoring, noncomplete automation of the platform and the absence of a dedicated telemedicine team still represent major limitations to be overcome. This is especially true in our real-life setting where the target population generally comprises patients of older age with a low digital education level.

Germline genetic testing for patients with severe aplastic anemia (SAA) is recommended to guide treatment, including the use of immunosuppressive therapy and/or adjustment of hematopoietic cell transplantation (HCT) modalities. Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory condition often associated with cytopenias with autosomal recessive (AR) or X-linked recessive (XLR) inheritance. HLH is part of the SAA differential diagnosis, and genetic testing may identify variants in HLH genes in patients with SAA. The impact of pathogenic/likely pathogenic (P/LP) variants in HLH genes on HCT outcomes in SAA is unclear. In this study, we aimed to determine the frequency of HLH gene variants in a large cohort of patients with acquired SAA and to evaluate their association(s) with HCT outcomes. The Transplant Outcomes in Aplastic Anemia project, a collaboration between the National Cancer Institute and the Center for International Blood and Marrow Transplant Research, collected genomic and clinical data from 824 patients who underwent HCT for SAA between 1989 and 2015. We excluded 140 patients with inherited bone marrow failure syndromes and used exome sequencing data from the remaining 684 patients with acquired SAA to identify P/LP variants in 14 HLH-associated genes (11 AR, 3 XLR) curated using American College of Medical Genetics and Genomics/Association of Molecular Pathology (ACMG/AMP) criteria. Deleterious variants of uncertain significance (del-VUS) were defined as those not meeting the ACMG/AMP P/LP criteria but with damaging predictions in ≥3 of 5 meta-predictors (BayesDel, REVEL, CADD, MetaSVM, and/or EIGEN). The Kaplan-Meier estimator was used to calculate the probability of overall survival (OS) after HCT, and the cumulative incidence calculator was used for other HCT outcomes, accounting for relevant competing risks. There were 46 HLH variants in 49 of the 684 patients (7.2%). Seventeen variants in 19 patients (2.8%) were P/LP; 8 of these were loss-of-function variants. Among the 19 patients with P/LP HLH variants, 16 (84%) had monoallelic variants in genes with AR inheritance, and 3 had variants in XLR genes. PRF1 was the most frequently affected gene (in 8 of the 19 patients). We found no statistically significant differences in transplantation-related factors between patients with and those without P/LP HLH variants. The 5-year survival probability was 89% (95% confidence interval [CI], 72% to 99%) in patients with P/LP HLH variants and 70% (95% CI, 53% to 85%) in those with del-VUS HLH variants, compared to 66% (95% CI, 62% to 70%) in those without variants (P = .16, log-rank test). The median time to neutrophil engraftment was 16 days for patients with P/LP HLH variants and 18 days in those with del-VUS HLH variants or without variants combined (P = .01, Gray\'s test). No statistically significant associations between P/LP HLH variants and the risk of acute or chronic graft-versus-host disease were noted. In this large cohort of patients with acquired SAA, we found that 2.8% of patients harbored a P/LP variant in an HLH gene. No negative effects of HLH gene variants on post-HCT survival were noted. The small number of patients with P/LP HLH variants limits the study\'s ability to provide conclusive evidence; nonetheless, our data suggest that there is no need for special transplantation considerations for patients with SAA carrying P/LP variants.

Mesenchymal stromal cells (MSCs) have been used in multiple clinical trials for steroid-refractory moderate-severe (grade II-IV) acute graft-versus-host disease (aGVHD) across the world over the last two decades. Despite very promising results in a variety of trials, it failed to get widespread approval by regulatory agencies such as the U.S. Food and Drug Administration and the European Medicines Agency. What lessons can we learn from this for future studies on MSCs and other cell therapy products? Broad heterogeneity among published trials using MSCs in aGVHD was likely the core problem. We propose a standardized approach in regards to donor-related factors, MSCs-related characteristics, as well as clinical trial design, to limit heterogeneity in trials for aGVHD and to fulfill the requirements of regulatory agencies. This approach may be expanded beyond MSCs to other Cell and Gene therapy products and trials in other diseases.