Allogeneic Hematopoietic Stem Cell Transplantation Recipients Research Articles

Persistent Impairment in Immune Reconstitution and Worse Survival Outcomes in Allogeneic Stem Cell Transplantation Patients with Early Coronavirus Disease 2019 Infection

Patients undergoing allogenic hematopoietic stem cell transplantation (HSCT) are at an increased risk of mortality due to transplantation-related complications in the first year post-transplantation, owing in part to the profound immune dysregulation with T cell and B cell lymphopenia and functional impairment. Although several large studies have reported higher mortality rates from Coronavirus disease 2019 (COVID-19) in HSCT recipients, to date no study has focused on the impact of early COVID-19 infection on immune reconstitution post-transplantation and the correlation with transplantation outcomes. We retrospectively analyzed 61 consecutive adult patients who underwent their first allogeneic HSCT at our institution. Thirteen patients (21.3%) experienced early COVID-19 infection, with a median time to diagnosis of 100 days post-transplantation. In multivariable analysis, patients with early COVID-19 infection had significantly worse overall survival (adjusted hazard ratio [aHR], 4.06; 95% confidence interval [CI], 1.26 to 13.05; P = .019) and progression-free survival (aHR, 6.68; 95% CI, 2.11 to 21.11; P = .001). This was attributed mainly to higher nonrelapse mortality (NRM) among early COVID-19 patients (P = .042). Allogeneic HSCT recipients with early COVID-19 infection had significant delays in absolute lymphocyte count (95% CI, -703.69 to -56.79; P = .021), CD3+CD4+ cell (95% CI, -105.35 to -11.59; P = .042), CD3+CD8+ cell (95% CI, -324.55 to -57.13; P = .038), and CD3-CD56+ cell (95% CI, -193.51 to -47.31; P = .014) recovery compared to those without early COVID-19 infection. Our findings suggest that patients with early COVID-19 infection after allogeneic HSCT have higher NRM and worse survival, at least in part due to impaired immune reconstitution post-transplantation.

High rates of intestinal colonization with carbapenemase producing Enterobacteriaceae inhematopoietic stem cell transplant recipients.

Carbapenem resistant Enterobacteriaceae (CRE) are major human pathogens because, these cause high number of difficult-to-treat infections. Allogeneic hematopoietic stem cell transplant (AHSCT) recipients are highly exposed to these type of bacteria. The aim of our study was to investigate prevalence of CRE colonization in AHSCT patients and to determine genes encoding carbapenem resistance. Aretrospective study conducted between January 2015 and December 2019, involved 55 patients colonized with CRE strains. We determined the rate of antibiotic resistance according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) and the carbapenem resistance genes by PCR assays for genes encoding most frequent β-lactamases namely, blaGES, blaKPC, blaIMI, blaNDM, blaVIM, blaIMP and blaOXA-48. Eighty-one episodes of CRE colonization were recorded in 55 patients, mainly suffering from acute leukaemia (30%) and aplastic anemia (26%). History of hospitalization was noted in 80 episodes. Prior antibiotic treatment, severe neutropenia and corticosteroid therapy were respectively found in 94%, 76% and 58% of cases. Among the 55 patients, six patients (11%) developed a CRE infection. The CRE responsible for colonization were carbapenemase producers in 90% of cases. They belonged mostly to Klebsiella pneumoniae (61/81) and Escherichia coli species (10/81). Antibiotic resistance rates were 100% for ertapenem, 53% for imipenem, 42% for amikacin, 88% for ciprofloxacin and 27% for fosfomycin. Molecular study showed that blaOXA-48 gene was the most frequent (60.5%), followed by blaNDM (58%). Thirty-five (43%) strains were co-producers of carbapenemases. In our study, we report a high rate of CRE intestinal colonization in AHSCT recipients of our center.

What Are the Perceptions of Recipients of Allogeneic Hematopoietic Stem Cell Transplant About Medication Adherence?: A Synthesis of Qualitative Studies.

Recipients of allogeneic hematopoietic stem cell transplant (HSCT) may encounter difficulties in adhering to their post-transplant medication as prescribed to avoid complications. Despite the relevance of patients' perspectives to inform the clinical practice, to date, no summary regarding their lived experience of oral medication adherence (MA) has been produced. To summarize the lived experience of MA by recipients of allogeneic HSCT as documented in qualitative studies. A systematic review and meta-synthesis of qualitative research was performed. Six databases were searched up to June 27, 2023. Four qualitative studies met eligibility and were included: those designed and conducted with scientifically sound methodologies and those regarding adult patients who had undergone allogeneic HSCT and required an oral medication regimen in the post-transplant phase. Data were extracted and synthesized using thematic analysis. Four analytical themes were identified: "The initiation is a challenge," "Time as a new issue," "Internal and external obstacles threaten medication adherence," and "Different strategies are the answer to medication non-adherence." Medication adherence in patients after HSCT is a complex phenomenon wherein different factors play a role. When designing targeted interventions to improve MA, it is imperative to start with patients' experiences and perspectives. Patients developed different strategies to deal with obstacles to MA that may inform daily practice. Before discharge, healthcare professionals should emphasize to both patients and carers the importance of MA.

Immunogenicity and Tolerance of BNT162b2 mRNA Vaccine in Allogeneic Hematopoietic Stem Cell Transplant Patients.

Allogeneic hematopoietic stem cell transplantation (ASCT) induces acquired immunodeficiency, potentially altering vaccine response. Herein, we aimed to explore the clinical tolerance and the humoral and cellular immune responses following anti-SARS-CoV-2 vaccination in ASCT recipients. A prospective, non-randomized, controlled study that involved 43 ASCT subjects and 31 healthy controls. Humoral response was investigated using the Elecsys® test anti-SARS-CoV-2. Cellular response was assessed using the QFN® SARS-CoV-2 test. The lymphocyte cytokine profile was tested using the LEGENDplex™ HU Th Cytokine Panel Kit (12-plex). Adverse effects (AE) were observed in 69% of patients, encompassing pain at the injection site, fever, asthenia, or headaches. Controls presented more side effects like pain in the injection site and asthenia with no difference in the overall AE frequency. Both groups exhibited robust humoral and cellular responses. Only the vaccine transplant delay impacted the humoral response alongside a previous SARS-CoV-2 infection. Noteworthily, controls displayed a Th1 cytokine profile, while patients showed a mixed Th1/Th2 profile. Pfizer-BioNTech® anti-SARS-CoV-2 vaccination is well tolerated in ASCT patients, inducing robust humoral and cellular responses. Further exploration is warranted to understand the impact of a mixed cytokine profile in ASCT patients.

Gratitude, optimism, and satisfaction with life and patient-reported outcomes in patients undergoing hematopoietic stem cell transplantation.

Associations between positive psychological well-being (PPWB) and patient-reported outcomes (PROs, e.g., quality of life [QOL]) have yet to be studied extensively in patients with hematologic malignancies who are allogeneic hematopoietic stem cell transplant (HSCT) survivors, despite substantial evidence that PPWB impacts PROs of other medical populations. We conducted a secondary analysis of cross-sectional data examining the association of PPWB and PROs at day 100 post-transplant among 158 allogeneic HSCT recipients. Optimism, gratitude, life satisfaction, and PROs (i.e., QOL, anxiety, depression, and PTSD symptoms) were assessed using the Life Orientation Test-Revised, Gratitude Questionnaire, Satisfaction with Life Scale, Functional Assessment of Cancer Therapy-Bone Marrow Transplant, Hospital Anxiety and Depression Scale, and Post-Traumatic Stress Disorder (PTSD) Checklist-Civilian Version, respectively. We used linear and multivariate regressions for all analyses and controlled for patient factors. Optimism was associated with better QOL (β=1.46; p<0.001) and lower levels of anxiety (β=-0.28; p<0.001), depression (β=-0.31; p<0.001), and PTSD (β=-0.58; p<0.001). Gratitude was associated with better QOL (β=1.11; p<0.001) and lower levels of anxiety (β=-0.21; p=0.001), depression (β=-0.14; p=0.021), and PTSD (β=-0.32; p=0.032). Finally, satisfaction with life was associated with better QOL (β=1.26; p<0.001) and lower levels of anxiety (β=-0.18; p<0.001), depression (β=-0.21; p<0.001), and PTSD (β=-0.49; p<0.001). Optimism, gratitude, and satisfaction with life were all associated with better QOL and lower levels of psychological distress in allogeneic HSCT survivors. These data support studies to harness PPWB as a therapeutic intervention for this population throughout HSCT recovery.

A Positive Psychology Intervention for Caregivers of Hematopoietic Stem Cell Transplantation Survivors (PATH-C): Initial Testing and Single-Arm Pilot Trial

Caregivers of patients with hematologic malignancies undergoing allogeneic hematopoietic stem cell transplantation (HSCT) play a crucial role in supporting their loved ones through physical, emotional, and practical challenges. This role has been associated with high levels of psychological distress and low levels of positive psychological well-being (PPWB). Positive psychology interventions for caregivers in other disease groups (eg, breast cancer) have been associated with improved outcomes. However, positive psychology interventions that specifically address HSCT caregivers' psychological needs are currently lacking. The goal of this single-arm open-pilot trial was to determine the feasibility and acceptability of the Positive Affect in the Transplantation of Hematopoietic Stem Cells (PATH) intervention for HSCT Caregivers to identify caregiver preferences to tailor PATH for HSCT caregivers. Adult caregivers of HSCT recipients were eligible for PATH during the HSCT recipient's first 100 d post-transplant. We defined, a priori, feasibility as >60% of participants who start the intervention completing ≥6/9 intervention sessions and acceptability as weekly ratings of ease and utility of the PP exercises ≥7/10 on a 10-point Likert Scale (0 = very difficult/not helpful; 10 = very easy/very helpful). We conducted semistructured qualitative exit interviews (n = 15) to explore HSCT caregivers' perception of PATH's content, benefits of PATH, as well as facilitators and barriers to engaging with the intervention. Transcribed interviews were analyzed using framework-guided rapid analysis by 2 coders. The intervention was feasible with 83% (15/18) of caregivers who started the intervention completing ≥6/9 intervention sessions. Among caregivers who completed ≥6/9 intervention sessions, ratings of ease (mean = 8.1; 95% CI: 7.4, 8.7) and utility (mean = 8.3; 95% CI: 7.8, 8.9) also exceeded our a priori threshold of ≥7/10. Caregivers identified benefits of PATH, including identifying and responding to emotions, dedicating time to self-care, and cultivating important relationships. Sociodemographic factors (eg, being retired) and the manualized structure of PATH were cited as facilitators to intervention engagement. Barriers to PATH engagement included lack of time and competing caregiving responsibilities. Caregivers preferred remote intervention delivery within the first 100 d post HSCT. This is the first study to show a 9-wk, phone-delivered positive psychology intervention is feasible in caregivers of allogeneic HSCT recipients. Our findings also underscore the specific preferences of this population for positive psychology interventions. Larger studies are warranted to establish the efficacy of these interventions in addressing persistent unmet psychological needs for HSCT caregivers.

Efficacy and Safety of Tixagevimab-Cilgavimab (Evusheld or AZD7442) As Pre-Exposure Prophylaxis for COVID-19 Among Allogeneic Hematopoietic Stem Cell Transplant Recipients

Background: Tixagevimab-Cilgavimab (Evusheld or AZD7442) is a combination of two monoclonal antibodies directed against viral spike proteins from binding to hosts' enzyme receptors, thus blocking viral entry into cells. The drug is FDA approved for use as pre-exposure prophylaxis (PrEP) in immunocompromised patients including Allogeneic hematopoietic stem cell transplant (Allo-HSCT) recipients. It has potential to both prevent and treat COVID-19, reducing incidence of severe infections and death for up to 6 months. Allo-HSCT patients are at higher risk of COVID-19, and may fail to mount a robust immune response to vaccination. In this study, we investigate the efficacy and safety of Evusheld in Allo-HSCT recipients 6 months following transplant at our institution. Methods: We performed a retrospective analysis of Allo-HSCT recipients treated at our institution between January 2021 to January 2023. Descriptive statistics related to the participant baseline characteristics, treatment, and transplant data were reported. The incidence of COVID-19 infections and safety data between two groups (Evusheld versus non-Evusheld) were estimated. Results: A total of 48 Allo-HSCT recipients were included in our study, 23 (47.9%) patients received PrEP Evusheld. The median age at transplant was 54.6 years. Patients were predominantly males (58.3%). Notable comorbidities included hypertension (56.3%), diabetes (20.8%), hyperlipidemia (27.1%), and cardiovascular diseases (20.8%). Indications for transplant included acute myeloid leukemia (47.9%), acute lymphocytic leukemia (6.3%), chronic myelogenous leukemia (8.3%), myelodysplastic syndromes (18.8%), and other hematologic malignancies (18.8%) (Table 1). The efficacy and safety results of Evusheld were shown in Table 2. The median time from transplant to Evusheld administration was approximately 100 days. There was no significant difference in the incidence of Covid infection (RR=0.842, 95% CI: 0.196-3.615, p=1.00) or severe Covid infection (RR=0.69, 95% CI: 0.10-4.60, p=1.00) between the two groups following transplant. All-cause mortality (death or hospice) was also comparable between the two groups (RR=0.375, 95% CI: 0.080-1.748, p=0.272). The rate of severe acute graft-versus-host (GVHD) and infections were comparable between the two groups, including clostridium difficile, cytomegalovirus (CMV), BK virus, human herpesvirus-6 (HHV-6), Epstein-Barr virus (EBV), and other bacterial and fungal infections. Conclusions: Our study found no evidence of efficacy of Evusheld against COVID-19 after Allo-HSCT transplant. This lack of efficacy may be attributed to the emergence of the XBB.1.5 subvariant of omicron during the study period. We also found no difference in all-cause mortality between the two groups. Further data is required to gain a comprehensive understanding of the potential use of Evusheld in transplant populations.

Infectious and Non-Infectious Pulmonary Complications in HCT Patients Treated with Post Transplant Cyclophosphamide (PTCy) Based Gvhd Prophylaxis

Introduction: Pulmonary complications are a leading cause of mortality and morbidity amongst pts undergoing hematopoietic stem cell transplantation (HCT). Increasingly, allogeneic HCT recipients are undergoing HCT with PTCy based GVHD prophylaxis. While lower rates of severe GVHD has been reported with PTCy, increased infection and organ toxicity has also been seen compared with standard calcineurin inhibitor (CNI) prophylaxis. The incidence and outcomes of pulmonary complications, both infectious and non-infectious/immune in pts receiving PTCy remain poorly characterized. Therefore, we aimed to assess for these in this study. Methods: We performed a retrospective review of pts between 2012-2022 who underwent 1st allogeneic BMT and received PTCy as part of GVHD prophylaxis. We identified pts requiring hospitalization for pulmonary complications. Infectious cases were categorized as bacterial, fungal, viral, or mixed. Bacterial pneumonia was defined as fever, cough, dyspnea, purulence sputum, and new or progressive radiographic evidence of infiltrate not explained by a non-infectious cause, treated with at least 5 days of antibiotics. Viral and fungal pneumonia were diagnosed based on identified organism. Noninfectious complications included idiopathic pulmonary syndrome (IPS), diffuse alveolar hemorrhage (DAH), cryptogenic organizing pneumonia (COP), and bronchiolitis obliterans syndrome (BOS). IPS was defined as radiographic evidence of alveolar infiltrates, dyspnea, cough, increased work of breathing or oxygen requirements, exclusion of infection or alternate pathology, and treated with high-dose systemic corticosteroids. DAH was defined as radiographic evidence of widespread alveolar injury, increased work of breathing or oxygen requirements, and persistent and progressive bloody return on BAL. COP was defined as pathologic evidence of organizing pneumonia on transbronchial lung biopsy in the absence of pathogens. BOS was defined as FEV1/FVC &amp;lt;0.7 and FEV1 &amp;lt;75% with a ≥10% decline over &amp;lt;2 years. Results: A total of 224 pts were identified. Median age at HCT was 55 years (20-78) (Table 1). 138 (64%) were male. The median comorbidity index (HCT-CI) score was 3 and median Karnofsky Performance Score was 80. 56%(n=125) pts underwent HCT with nonmyoablative conditioning, 78% (n=157) underwent HCT with a haploidentical donor, and 65% (n=145) of grafts were peripheral blood. 4%(n=10) were current smokers at time of HCT, 38% (n=84) were former smokers. 16% (n=35) had an existing diagnosis of asthma or COPD. 72 (32%) pts were hospitalized for pneumonia at any point after HCT. There were 23 bacterial pneumonias (30%), 20 viral (27%), 13 fungal (18%), and 12 were mixed (17%) (Table 2). There were 4 pts (6%)with documented pneumonia of unknown etiology due to rapid progression to death or hospice. 10 pts (4%) developed IPS with a median onset of 153 days (20-354). 2 pts (1%) developed COP with a mean onset of 754 days (388 - 1119). 5 pts (2%) developed BOS with a median onset of 336 days (153-677). 8 pts (4%) developed DAH with a median onset of 48 days (20-152). Among all patients, 57 pts (25%) required mechanical ventilation at any point post-HCT, and 18 pts (8%) were prescribed home oxygen at any point post-HCT. Overall, 80pts (77%) died due to non-relapse causes. 29 deaths (28%) were pulmonary related, (21 (20%) infectious and 8 (8%) noninfectious). Of the noninfectious pulmonary deaths, 3 pts died due to IPS, and 5 died due to DAH. Conclusion: In our cohort of pts receiving PTCy based GVHD prophylaxis, significant infectious pulmonary complications were common and were fatal in 9.4% of pts. Infections were the major driver of pulmonary related mortality, however, we observed noninfectious/immunologic pulmonary complications at a rate within or only slightly below the previously reported ranges among transplanted pts predominantly receiving CNI based prophylaxis.

Treatment of Refractory Adenovirus (ADV) Infections Using Adv-Specific Cytotoxic T-Lymphocytes (CTLs) in Children, Adolescents and Young Adults (CAYA) Post Allogeneic Hematopoietic Stem Cell Transplantation (AlloHSCT), Solid Organ Transplantation (SOT), or with Primary Immunodeficiency (PID)

Background: AlloHSCT induces long-term, cure in CAYA with malignant and non-malignant disorders, including those with primary immunodeficiencies (PID). However, post-transplant complications secondary to immunosuppression and slow or delayed immune reconstitution remains a cause of morbidity and mortality amongst AlloHSCT recipients (Satwani/Cairo, BBMT, 2009). Major complications include refractory viral infections, most importantly adenovirus (ADV), which is secondary to absent or decreased adenovirus specific T-cell immunity which occurs due to delayed immune reconstitution and/or continued immunosuppression (George/Cairo, BJH, 2012). The use of virus-specific (vs) CTLs in immunocompromised patients offer an opportunity to restore temporary virus specific immunity. From the Viral Cytotoxic T-Lymphocyte Consortium (VIRCTLC), we present safety and efficacy results on immune compromised, AlloHSCT, or SOT patients treated with familial ADV specific CTLs. Objective: Determine the safety and efficacy of familial ADV specific CTLs for the treatment of refractory systemic ADV infections. Design/Methods: Patient were deemed eligible if they had a history of AlloHSCT, SOT, or PID and had evidence of ADV infections refractory to anti-viral agents. Refractory ADV infection was defined by increasing serum RT-PCR DNA (by 1 log) after 7 days or persistent quantitative RT-PCR DNA copies after 14 days of appropriate anti-viral therapy, and/or known resistance/intolerance to anti-viral agents. Related donors were required to be matched ≥3 HLA (A, B, or DRB1) loci and have an adequate T-cell response to viral specific MACS ADV PepTivators®. We chose a direct selection method to facilitate more rapid generation of cellular products in a point of care setting (and with 14 hrs eligibility determination). Peripheral blood mononuclear cells were collected from eligible family donors using non-mobilized apheresis. vsCTLs were isolated using the CliniMACS ® Prodigy following stimulation with viral specific MACS® GMP PepTivator® AdV5 Hexon, generously provided by Miltenyi Biotec®. ADV specific CTLs were enriched using a Cytokine Capture System (CCS). CD4+ and CD8+ vsCTLs were quantified by flow cytometry (Feuchtinger et al, Blood, 2010). The target cell dose was 0.5x10 4 CD3+ cells/kg (recipient weight) for haploidentical related donors and 2.5x10 4 CD3+ cells/kg for matched related donors. Repeated doses were permitted every 2 weeks to a maximum of doses in the absence of a complete response (CR) and adverse events. The following were used to define response: CR - undetected ADV PCR, partial response (PR) - at least one log decrease from baseline, progressive disease (PD) - at least one log increase from baseline, and patients with stable disease. Results: Fifteen patients were enrolled: 10 females and 5 males; aged 1-19 years. All patients were post-AlloHSCT. All vsCTL donors were haploidentical: 8 were the original HSCT donors and 7 were third party donors (5 maternal, 2 paternal). The mean number of ADV CTL infusions was 3.7 (range: 1-16). One patient with underlying aplastic anemia had progressive disease complicated by increased adenoviral load despite 5 infusions of vsCTLs. Patient received FDA approval for additional CTLs, totaling 16 doses. Thirteen patients achieved CR as defined and 2 achieved PR. The overall response (OR) was 100% and the CR was 88%. The average time to OR was 33 days (range 6-112 days) and time to CR was 34 days (range 6-112 days). Day 100 and 365 overall survival (OS) post-HSCT was 86.1% (CI95: 49.4-95.7) and 70.5% (CI95: 38.9-87.8), respectively (Figure 1). For patients who achieved CR, the Day 100 OS post AlloHSCT was 83.9% (CI95: 55.0-94.3) and Day 365 post AlloHSCT was 74.6% (CI95: 39.8-91.1). Day 100 and 365 probability of ADV related mortality was 0% (Figure 2). One patient developed acute grade 2 skin GVHD possibly related to infusion, which resolved. Conclusion: Our preliminary data demonstrate that haploidentical ADV specific CTLs manufactured by direct selections using the CCS with the CliniMACS® Prodigy and ADV specific peptivators are safe, well-tolerated, and efficacious in patients with refractory/persistent ADV infections after AlloHSCT. Manufacturing is rapid, reproducible, and effective. Accrual is ongoing. This research is supported by FDA RO1006301A1.

Richter transformation – retrospective treatment outcomes analysis in Polish Adult Leukemia Study Group

Richter transformation (RT) is defined as developing an aggressive lymphoma in 2–10% of patients suffering from chronic lymphocytic leukemia (CLL). So far, no complex analysis of RT demographics and treatment outcomes has been performed in Poland. Thus, the retrospective analysis of 124 patients with RT from Polish hematology centers was designed. Ninety-nine patients with diffuse large B-cell lymphoma (DLBCL-RT) were identified. The median overall survival (OS) for DLBCL-RT was 17.3 months, while for Hodgkin lymphoma (HL-RT)-21.3 months. In multivariate analysis, the independent factors of worse OS for DLBCL-RT were: prior CLL therapy, ECOG stage ≥2, and elevated serum LDH activity. Patients who proceeded to hematopoietic stem cell transplantation (HSCT) achieved better results. The median OS in allogeneic HSCT recipients was not reached, while in autologous HSCT median OS was 51.3 months. In conclusion, our study represents the largest dataset of patients diagnosed with RT in Poland and confirms its dismal prognosis.

QuantiFERON-CMV and monitor predict cytomegalovirus, mortality, and graft-versus-host disease in transplant recipients.

Cytomegalovirus (CMV) is the most prevalent infection in recipients of hematopoietic stem cell transplant (HSCT). QuantiFERON-CMV (QF-CMV) and QuantiFERON-Monitor (QFM) assays were used to test whether immune-competent adult allogeneic HSCT recipients with CMV-specific T cells can control CMV infection or reactivation. Our data demonstrated a significant correlation between CMV infection measured by CMV-antigenemia test and QF-CMV results, graft versus host disease (GvHD), and mortality rates. The QF-CMV test revealed that CMV-specific T cells with higher interferon-γ (IFN-γ) release were correlated with lower CMV infection rates. There was a significant negative association between QF-CMV results, GvHD, and mortality rates. Data showed that a one-unit rise in IFN-γ was linked with a 12.7% reduction in GvHD and a 20.7% reduction in the mortality odds ratio. In addition, a negative correlation was found between QF-M results and CMV infection, with the QFM test predicting protection against CMV infection by 1.9%. This is one of the few studies establishing the QF-CMV test's predictive value for GvHD and mortality, its use to monitor HSCT patients for pre-emptive therapy, and the use of the QFM test to predict CMV infection and mortality in HSCT patients. Thus, these assays could be utilized to optimize preventive and pre-emptive therapy procedures to reduce transplant recipient adverse effects and posttransplant therapy costs.

Feasibility of a dietary intervention to modify gut microbial metabolism in patients with hematopoietic stem cell transplantation

Evaluation of the impact of dietary intervention on gastrointestinal microbiota and metabolites after allogeneic hematopoietic stem cell transplantation (HCT) is lacking. We conducted a feasibility study as the first of a two-phase trial. Ten adults received resistant potato starch (RPS) daily from day −7 to day 100. The primary objective was to test the feasibility of RPS and its effect on intestinal microbiome and metabolites, including the short-chain fatty acid butyrate. Feasibility met the preset goal of 60% or more, adhering to 70% or more doses; fecal butyrate levels were significantly higher when participants were on RPS than when they were not (P < 0.0001). An exploratory objective was to evaluate plasma metabolites. We observed longitudinal changes in plasma metabolites compared to baseline, which were independent of RPS (P < 0.0001). However, in recipients of RPS, the dominant plasma metabolites were more stable compared to historical controls with significant difference at engraftment (P < 0.05). These results indicate that RPS in recipients of allogeneic HCT is feasible; in this study, it was associated with significant alterations in intestinal and plasma metabolites. A phase 2 trial examining the effect of RPS on graft-versus-host disease in recipients of allogeneic HCT is underway. ClinicalTrials.gov registration: NCT02763033.

Immunogenicity and Safety of Booster SARS-CoV-2 mRNA Vaccine Dose in Allogeneic Hematopoietic Stem Cell Transplantation Recipients

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients are susceptible to severe outcomes of Coronavirus disease 2019 (COVID-19). Most guidelines recommend a fourth dose (ie, booster) of COVID-19 vaccine to reduce the infection risk, and observational studies are needed to determine the immunogenicity and safety of the booster dose in this population. The primary outcome was to determine the quantitative anti-receptor-binding domain (RBD) antibody titers after the fourth dose of the COVID-19 vaccine. The secondary outcomes included adverse effects and all-cause mortality. This single-group prospective cohort included allogeneic HSCT recipients age ≥18 years who received their fourth dose of COVID-19 mRNA vaccine between December 15, 2021, and August 2, 2022. We excluded patients with a history of COVID-19 diagnosis and those who received i.v. Ig within 21 days of antibody testing or rituximab within 6 months before study entry. We used regression models to determine the contributing factors significantly associated with post-fourth dose anti-RBD titer. Sixty-seven patients (median age, 59.5 years; IQR, 53.5 to 65.5 years; 33 males [61%]) received the fourth dose of vaccine, and 54 were included in the anti-RBD titer analysis. The median anti-RBD titers at 4 to 6 weeks after the third and fourth doses differed significantly (13,350 U/mL [IQR, 2618 to 34,740 U/mL] and 44,500 U/mL [IQR, 11,163 to 84,330 U/mL], respectively; P < .0001). In univariate analysis, the post-third dose anti-RBD titer (β=.70; 95% CI, .54 to .87; P < .001) and treatment with mycophenolate compounds (β=-1.05; 95% CI, -1.97 to -1.12; P=.03) significantly predicted the antibody response to the fourth dose. In multivariate analysis, the inverse association between treatment with mycophenolate compounds and the post-fourth dose anti-RBD antibody titer was not significant (β=-.57; 95% CI, -1.32 to .19; P=.14), whereas the significant association between the anti-RBD titers following the third and fourth doses did not change considerably (β=.66; 95% CI, .47 to .86; P < .001). The most frequent adverse event was vaccination site soreness (44%), followed by fatigue (16%), myalgia (4%), and headache (2%). No recipient experienced new or worsened preexisting graft-versus-host disease within 40 days of vaccination, and no patient died. Six patients (11%) developed breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection not associated with hospitalization or severe outcomes. The fourth dose of the COVID-19 vaccine appears to be highly immunogenic and safe in allogeneic HSCT recipients. Further studies are needed to determine the neutralizing antibody titers against SARS-CoV-2 subvariants and the effectiveness and immunogenicity of bivalent vaccines in allogeneic HSCT recipients.

From support to therapy: rethinking the role of nutrition in acute graft-versus-host disease.

Allogeneic Hematopoietic stem cell transplantation (HSCT) offers a potential cure for patients with hematologic malignancies. Unfortunately, graft-versus-host disease (GVHD) remains a major obstacle to the greater success of this treatment. Despite intensive research efforts over the past several decades, GVHD is still a major cause of morbidity and mortality in patients receiving allogeneic HSCT. The genetic disparity between donor and recipient is the primary factor that dictates the extent of alloimmune response and the severity of acute GVHD (aGVHD). However, some nongenetic factors are also actively involved in GVHD pathogenesis. Thus, identifying host factors that can be readily modified to reduce GVHD risk is of important clinical significance. We are particularly interested in the potential role of nutrition, as a nongenetic factor, in the etiology and management of aGVHD. In this article, we summarize recent findings regarding how different routes of nutritional support and various dietary factors affect aGVHD. Since diet is one of the most important factors that shape gut microbiota, we also provide evidence for a potential link between certain nutrients and gut microbiota in recipients of allogeneic HSCT. We propose a shifting role of nutrition from support to therapy in GVHD by targeting gut microbiota.

What do patients think about palliative care? A national survey of hematopoietic stem cell transplant recipients.

Palliative care (PC) benefits patients undergoing hematopoietic stem cell transplantation (HSCT), but it remains underutilized. Although transplant physicians report concerns regarding how patients perceive PC, HSCT recipients' perceptions about PC remain unaddressed. We conducted a multisite, cross-sectional survey of autologous and allogeneic HSCT recipients 3 to 12months after transplant to assess their familiarity, knowledge, and perception of PC, as well as their unmet PC needs. We computed a composite score of patients' perceptions of PC and used a generalized linear regression model to examine factors associated with these perceptions. We enrolled 69.6% (250/359) of potential participants (median age= 58.1; 63.1% autologous HSCT). Overall, 44.3.8% (109/249) reported limited knowledge about PC and 52% (127/245) endorsed familiarity with PC. Most patients felt hopeful (54%) and reassured (50%) when they heard the term PC; 83% saw referral as a sign their doctor cared about what was happening to them. In multivariate analyses, patients who were more knowledgeable about PC were more likely to have positive perceptions of PC (B= 7.54, standard error= 1.61, P< .001). Patients' demographics, HSCT features, quality of life, and symptom burden were not significantly associated with perceptions of PC. HSCT recipients have positive perceptions of PC, though many have limited knowledge about its role. Patients who were more knowledgeable about PC were more likely to have positive perceptions of PC. These data do not support transplant physicians' negative concerns about how patients perceive PC and underscore the need to further educate patients and transplant physicians about PC.

Clinical Features of Acute Kidney Injury in the Early Post-Transplantation Period Following Reduced-Intensity Conditioning Allogeneic Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (HCT) is a potentially curative therapy for patients with hematologic malignancies but is associated with acute kidney injury (AKI). To date, few studies have examined risk factors for AKI at engraftment, or the relationship of AKI with clinical outcomes. This study examined the incidence and risk factors for periengraftment AKI, as well as the association between AKI and overall survival (OS) and nonrelapse mortality (NRM). We conducted a retrospective analysis of adult patients undergoing reduced-intensity conditioning (RIC) allogeneic HCT at the Dana-Farber Cancer Institute between 2012 and 2019. Periengraftment (day 0 to day 30) AKI incidence and severity were defined using modified KDIGO (Kidney Disease: Improving Global Outcomes) criteria. Factors associated with periengraftment AKI risk were examined using Cox regression analysis. The impact of periengraftment AKI on OS and NRM (defined as death without recurrent disease after HCT), was evaluated using Cox regression and the Fine and Gray competing risks model, respectively. Kidney recovery, defined as a return of serum creatinine (SCr) within 25% of baseline or liberation from kidney replacement therapy (KRT), was examined at day 90 post-HCT. Periengraftment AKI occurred in 330 of 987 patients (33.4%) at a median of 13 days (interquartile range, 4 to 30 days) post-transplantation. Factors associated with a higher multivariable-adjusted risk of AKI were supratherapeutic rapamycin (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.20 to 2.03; P < .001), fludarabine/melphalan conditioning (HR, 1.35, 95% CI, 1.01 to 1.81; P = .05, compared to fludarabine/busulfan and fludarabine, cyclophosphamide, and total body irradiation), HCT Comorbidity Index ≥4 (HR, 1.43; 95% CI, 1.14 to 1.79; P = .002), albumin <3.4 g/dL (HR, 2.04; 95% CI, 1.33 to 3.12; P = .001), hemoglobin ≤12 (HR, 1.96; 95% CI, 1.38 to 2.78; P < .001), supratherapeutic tacrolimus (HR, 1.45; 95% CI, 1.07 to 1.95; P = .02), and baseline SCr >1.1 mg/dL (HR, 1.87; 95% CI, 1.48 to 2.35; P < .001). Periengraftment AKI was associated with worse OS (HR, 1.40; 95% CI, 1.16 to 1.71; P < .001) and NRM (subdistribution HR, 2.10; 95% CI, 1.52 to 2.89; P < .001). Kidney recovery occurred in 18%, 15%, and 30% of patients with stage 1, stage 2, and stage 3 AKI without KRT, respectively, and 4 of 16 patients (25%) were liberated from KRT. Periengraftment AKI is common among RIC allogeneic HCT recipients. We identified several important risk factors for periengraftment AKI. Its association with worse OS and NRM underscores the importance of timely recognition and management.

One-year mortality of hematopoietic stem cell recipients admitted to an intensive care unit in a dedicated Brazilian cancer center: a retrospective cohort study.

Hematopoietic stem cell transplantation (HSCT) recipients requiring intensive care unit (ICU) admission early after transplantation have a poor prognosis. However, many studies have only focused on allogeneic HSCT recipients. To describe the characteristics of HSCT recipients admitted to the ICU shortly after transplantation and assess differences in 1-year mortality between autologous and allogeneic HSCT recipients. A single-center retrospective cohort study in a cancer center in Brazil. We included all consecutive patients who underwent HSCT less than a year before ICU admission between 2009 and 2018. We collected clinical and demographic data and assessed the 1-year mortality of all patients. The effect of allogeneic HSCT compared with autologous HSCT on 1-year mortality risk was evaluated in an unadjusted model and an adjusted Cox proportional hazard model for age and Sequential Organ Failure Assessment (SOFA) at admission. Of the 942 patients who underwent HSCT during the study period, 83 (8.8%) were included in the study (autologous HSCT = 57 [68.7%], allogeneic HSCT = 26 [31.3%]). At 1 year after ICU admission, 21 (36.8%) and 18 (69.2%) patients who underwent autologous and allogeneic HSCT, respectively, had died. Allogeneic HSCT was associated with increased 1-year mortality (unadjusted hazard ratio, HR = 2.79 [confidence interval, CI, 95%, 1.48-5.26]; adjusted HR = 2.62 [CI 95%, 1.29-5.31]). Allogeneic HSCT recipients admitted to the ICU had higher short- and long-term mortality rates than autologous HSCT recipients, even after adjusting for age and severity at ICU admission.

Third BNT162b2 mRNA SARS-CoV-2 Vaccine Dose Significantly Enhances Immunogenicity in Recipients of Allogeneic Hematopoietic Stem Cell Transplantation.

COVID-19-related mortality among hematopoietic stem cell transplantation (HSCT) recipients in the pre-vaccine era ranged between 22 and 33%. The Pfizer/BioNTech BNT162b2 vaccine demonstrated significant immunogenicity and efficacy in the healthy population; however, its long-term effects on allogeneic HSCT recipients remained unclear. Our study longitudinally evaluated humoral and cellular responses to the BNT162b2 vaccine in adult allogeneic HSCT patients. A positive response was defined as antibody titers ≥ 150 AU/mL post-second vaccination. Among 77 included patients, 51 (66.2%) responded to vaccination. Response-associated factors were female gender, recent anti-CD20 therapy, and a longer interval between transplant and vaccination. Response rates reached 83.7% in patients vaccinated >12 months post-transplant. At 6 months post-second vaccination, antibody titers dropped, but were significantly increased with the booster dose. Moreover, 43% (6/14) of non-responders to the second vaccination acquired sufficient antibody titers after booster administration, resulting in an overall response rate of 79.5% for the entire cohort. The BNT162b2 vaccine was effective in allogeneic transplant recipients. Although antibody titers decreased with time, the third vaccination led to their significant elevation, with 93% of third-dose responders maintaining titers above 150 AU/mL at 3 months post-administration.

Predicted Bezlotoxumab Exposure in Patients Who Have Received a Hematopoietic Stem Cell Transplant

Bezlotoxumab is approved for prevention of recurrent Clostridioides (Clostridium) difficile infection (CDI) in adults receiving antibacterial treatment for CDI who are at high risk for recurrent CDI. Previous studies have shown that although serum albumin levels are an important predictor for bezlotoxumab exposure, this has no clinically meaningful impact on efficacy. This pharmacokinetic modeling study assessed whether hematopoietic stem cell transplant (HSCT) recipients, at increased risk of CDI and exhibiting decreased albumin levels within the first month posttransplant, are at risk of clinically relevant reductions in bezlotoxumab exposure. Observed bezlotoxumab concentration-time data pooled from participants in Phase III trials MODIFY I and II (ClinicalTrials.gov identifiers NCT01241552/NCT01513239) and three Phase I studies (PN004, PN005, and PN006) were used to predict bezlotoxumab exposures in two adult post-HSCT populations: A Phase Ib study of posaconazole including allogeneic HSCT recipients (ClinicalTrials.gov identifier NCT01777763; posaconazole-HSCT population); and a Phase III study of fidaxomicin for CDI prophylaxis (ClinicalTrials.gov identifier NCT01691248; fidaxomicin-HSCT population). The bezlotoxumab PK model used the minimum albumin level for each individual in post-HSCT populations to mimic a "worst-case scenario." Predicted worst-case bezlotoxumab exposures for the posaconazole-HSCT population (N=87) were decreased by 10.8% versus bezlotoxumab exposures observed in the pooled Phase III/Phase I data set (N=1587). No further decrease was predicted for the fidaxomicin-HSCT population (N=350). Based on published population pharmacokinetic data, the predicted decrease in bezlotoxumab exposure in the post-HSCT populations is not expected to have a clinically meaningful effect on bezlotoxumab efficacy at the recommended 10 mg/kg dose. Dose modification is therefore not required in the hypoalbuminemia setting expected post-HSCT.

Features of cytomegalovirus DNAemia and virus-specific T-cell responses in allogeneic hematopoietic stem-cell transplant recipients during prophylaxis with letermovir.

There is scarce information on the natural kinetics of cytomegalovirus (CMV) DNAemia and dynamics of CMV-specific T-cell reconstitution in allogeneic hematopoietic transplant recipients (allo-HSCT) undergoing letermovir (LMV) prophylaxis. Twelve adult CMV-seropositive high-risk recipients (median age, 53 years; 9 males/3 females) undergoing LMV prophylaxis and 13 non-LMV allo-HSCT controls (median age, 58 years; 7 males/6 females) were included. CMV DNAemia in plasma was monitored by real-time polymerase chain reaction. Preemptive antiviral therapy (PET) was administered upon detection of ≥1500IU/ml. CMV-specific interferon-gamma (IFN-γ)-producing CD8+ and CD4+ T cells were enumerated by flow cytometry around days +30, +60, and +90 after allo-HSCT. Ex vivo experiments assessing of the potential effect of LMV on CMV-specific T-cell expansion in a single CMV-seropositive donor were also conducted. Five LMV patients (41.6%) developed CMV DNAemia that cleared spontaneously. Four patients (33.3%) developed CMV DNAemia after LMV cessation, of which two required PET. Nine non-LMV patients (69.2%) developed CMV DNAemia (five required PET). The percentage of LMV and non-LMV patients exhibiting detectable CMV-specific T-cell responses was comparable (7/10 vs. 10/13; p=.71). Nevertheless, median CMV-specific CD4+ and CD8+ T-cell counts were lower in LMV patients by days +60 (p=.006 and .02, respectively) and +90 (p=.08 and .02). Ex vivo, CMV-specific CD8+ T cells expanded to the same level either in the presence (19.8%) or in the absence of LMV (20.6%). In our series, episodes of CMV DNAemia in LMV patients cleared spontaneously. A diminished degree of CMV-specific T-cell reconstitution in LMV patients compared to non-LMV patients was observed.