Incidence and Outcomes of Cytomegalovirus Reactivation after Chimeric Antigen Receptor T Cell Therapy.

Cytomegalovirus (CMV) reactivation is a major complication among seropositive allogeneic hematopoietic cell transplantation (HCT) recipients; however, data regarding CMV reactivation after chimeric antigen receptor T (CAR T) cell therapy are limited. In this single-center retrospective study, we report the incidence and outcomes of 95 adult CMV seropositive patients who received CAR T cell therapy between February 2018 and February 2023. CMV outcomes were CMV reactivation (any viremia) and clinically significant CMV infection (cs-CMV, viremia requiring antiviral treatment). Thirty-one patients (33%) had evidence of CMV reactivation (any viremia), and 10 patients (11%) had cs-CMV. The median time from CAR T cell infusion to CMV reactivation was 19 days (IQR, 9-31). The cumulative incidence of CMV (any viremia) was significantly higher among patients with grade 3-4 cytokine release syndrome (67 vs. 28%; P=0.01), and those who received corticosteroids (39 vs. 21%; P=0.03), anakinra (56 vs. 28%; P=0.02), or ≥2 immunosuppressants (41 vs. 21%; P=0.02). Receipt of corticosteroids (18 vs. 0%; P=0.004), tocilizumab (14 vs. 0%; P=0.04), anakinra (33 vs. 7%; P=0.008), and ≥2 immunosuppressants (20 vs. 0%; P=0.001) were all associated with cs-CMV. Receiving ≥2 immunosuppressants was associated with a 2-fold increase in CMV reactivation in multivariate analyses (aOR 2.27, 95%CI 1.1-4.8, P=0.03). Overall, 1-year mortality was significantly higher in those with CMV reactivation (57% vs. 23%, P=0.001). Immunosuppression, particularly corticosteroids, for the management of CAR T cell toxicities is a major risk factor for CMV reactivation. CMV preventive strategies in high-risk CAR T recipients might improve outcomes.

Successful restoration of protective immunity against measles, mumps, and rubella following MMR vaccination in adult hematopoietic cell transplant recipients.

BACKGROUND: The optimal number of doses as well as the role for measurement of postvaccination titers after measles, mumps, rubella (MMR) vaccination in adult hematopoietic cell transplantation (HCT) recipients remains unknown. METHODS: In the present study, we assessed humoral immunity against measles, mumps and rubella before and after MMR vaccination in 187 adults who received at least one dose of the MMR vaccine after HCT. RESULTS: Among those with baseline titers, posttransplant prevaccination seroprotection rates were 56%, 30%, and 54% for measles, mumps, and rubella, respectively; and significantly lower in allogeneic versus autologous HCT recipients for measles (39% vs. 80%, p = .0001), mumps (22% vs. 41%; p = .02) and rubella (48% vs. 62%, p = .12). Among those who were seronegative at baseline, seroconversion rates after one dose of MMR were 69%, 56%, and 97% for measles, mumps, and rubella, respectively. Seronegative patients after one dose of MMR (i.e., nonresponders) seroconverted for measles and mumps after a second MMR vaccine dose. CONCLUSION: Our findings demonstrate successful restoration of protective immunity against measles, mumps, and rubella after vaccination in adult HCT recipients; one dose of MMR elicited protective titers in the majority of patients, and a second vaccine dose was immunogenic in nonresponders.

Early administration of SARS-CoV-2 monoclonal antibody reduces the risk of mortality in hematologic malignancy and hematopoietic cell transplant patients with COVID-19.

BACKGROUND: Data on severe acute respiratory distress syndrome coronavirus 2 monoclonal antibody (SARS-CoV-2-specific mAb) use in hematologic malignancy and hematopoietic cell transplantation (HM/HCT) patients are limited. Here, we describe our experience with the use of casirivimab-imdevimab or bamlanivimab for the treatment of coronavirus disease 2019 (COVID-19) in HM/HCT patients. METHODS: This was a retrospective chart review at the University of Miami Hospital and Sylvester Comprehensive Cancer Center for HM/HCT patients with COVID-19 who received casirivimab-imdevimab or bamlanivimab from November 21, 2020, to September 30, 2021. Outcomes measured were mortality, hospital admission, and infusion reaction to SARS-CoV-2-specific mAbs. RESULTS: We identified 59 HM/HCT patients with mild to moderate COVID-19 who received casirivimab-imdevimab or bamlanivimab. Median age was 57 years (interquartile range [IQR]: 45-65). Among the 59 patients, 25 (42%) received cellular therapy: 14 (24%) had undergone allogeneic HCT, nine (15%) autologous HCT, and two (3%) received chimeric antigen receptor T-cell therapy. The median time from COVID-19 symptom onset to SARS-CoV-2-specific mAb administration was 4 (IQR: 3-6) days. Forty-six (78%) patients received SARS-CoV-2-specific mAbs as outpatients and 13 (22%) patients received SARS-CoV-2-specific mAbs during hospitalization. Among patients who received SARS-CoV-2-specific mAbs as outpatients, only four (9%) visited the emergency department at days 10, 11, 15, and 35 after SARS-CoV-2-specific mAb administration. None of these four patients required hospital admission. Among the hospitalized patients, five (38%) were admitted to the hospital with neutropenic fever, four (31%) were already hospitalized for transplantation and cellular therapy, three (23%) were admitted for monitoring of COVID-19 symptoms, and one (8%) was admitted with acute kidney injury. Three hospitalized patients (23%) died at 14, 35, and 59 days after SARS-CoV-2-specific mAb administration; two of these three deaths were attributed to COVID-19 infection. One patient developed an immediate infusion reaction to bamlanivimab, and no infusion reactions were reported to casirivimab-imdevimab use. CONCLUSION: During the alpha and delta variant surges, early administration of bamlanivimab or casirivimab-imdevimab prevented hospitalization and death when given in the outpatient setting. Among patients who received mAbs at or after hospital admission, the risk of COVID-19 disease progression and death remains significant. Larger studies of the use of mAb therapy to treat COVID-19 in this population are needed.

Successful Treatment of Disseminated Disease Due to Highly Resistant Aspergillus calidoustus with a Novel Antifungal Therapy.

Invasive aspergillosis is the most common invasive mold infection following a hematopoietic cell transplant. Widespread use of antifungal prophylaxis has led to the increasing incidence of cryptic Aspergillus species. Aspergillus calidoustus is one of those emerging species and is notorious for multidrug resistance to antifungals. Here, we report a case of disseminated A. calidoustus infection in a hematopoietic stem cell transplant recipient who was successfully treated with combination therapy that included a novel antifungal.

Lower Incidence of Cytomegalovirus Reactivation Following Post-Transplantation Cyclophosphamide HLA-Mismatched Unrelated Donor Transplantation.

The use of haploidentical or HLA-mismatched unrelated donors (MMUD) allows allogeneic hematopoietic cell transplantation in individuals without suitable matched donors. Post-transplantation cyclophosphamide (PTCy) is used routinely for prevention of graft-versus-host disease in recipients of haploidentical transplants, and its use has been recently explored in MMUD transplantation. We compared the incidence of cytomegalovirus (CMV) reactivation and rate of lymphocyte recovery between PTCy MMUD and alternative transplantation modalities. Single-center retrospective study of 22 consecutive PTCy MMUD recipients transplanted between April 2017 and January 2019. Patients undergoing anti-thymocyte globulin (ATG) MMUD (n = 37) and PTCy haploidentical transplantation (n = 19) between January 2015 and July 2018 served as historical controls. We assessed the incidence of CMV (any viremia) and clinically significant CMV reactivation (cs-CMVi; defined as CMV disease or CMV viremia leading to preemptive treatment) in these 3 groups. Immune reconstitution was assessed by absolute lymphocyte count (ALC) at days 30, 90, 180, and 360 after transplantation. Statistical analyses included Kaplan-Meier plots with a log-rank test, Kruskal-Wallis test, and Fisher's exact test where appropriate, and logistic regression analyses. For PTCy MMUD, PTCy haploidentical and ATG MMUD groups, the 100-day and 200-day incidence of CMV (any viremia) were 41%, 63%, and 77% (P = .02), and 64%, 68%, and 86% (P = .049), respectively. The rate of cs-CMVi was also lower in PTCy MMUD compared to PTCy haploidentical and ATG MMUD (14% versus 53% and 54% at day 100 [P = .01] and 25% versus 53% and 58% at day 200 [P = .03]). There was a trend toward lower 200-day incidence of cs-CMVi in PTCy MMUD compared to ATG MMUD, even after excluding letermovir-treated patients from the analysis (25% versus 58% [P = .06]). The association between PTCy MMUD and lower risk of cs-CMVi remained significant even after adjusting for letermovir prophylaxis (odds ratio = 0.23, 95% confidence interval, 0.07-0.81 [P = .02]). Day 30 ALC was lower in PTCy MMUD compared to PTCy haploidentical and ATG MMUD (0.14, 0.33, 0.44 × 109/L, respectively [P = .005) but similar across groups at other time points. PTCy MMUD transplantation was associated with lower incidence of CMV events, independent of the use of CMV prophylaxis. Larger studies are needed.

Viral kinetics and outcomes of adenovirus viremia following allogeneic hematopoietic cell transplantation.

BACKGROUND: Adenovirus (AdV) is a serious infection following hematopoietic cell transplantation (HCT). Little is known about AdV viral kinetics and optimal threshold for initiation of pre-emptive therapy. METHODS: Single-center retrospective study of 16 consecutive adult HCT recipients with detectable AdV identified over a 5-year period. RESULTS: Median time to AdV reactivation after HCT was 176 days (IQR 86-408). Nine patients received cidofovir, although 14/16 had no tissue-invasive disease. Among treated patients, median duration of viremia was shorter when initiating treatment at viral loads < 10,000 copies/ml (28 vs. 52 days). All-cause mortality in this cohort was 44%. All six patients (five of which were untreated) with peak viral loads < 10,000 copies/ml survived; whereas only 30% (3/10) of patients with peak viral loads greater than this threshold survived, despite most (n = 8; 80%) of them receiving cidofovir (P = .01). Three-month survival following diagnosis of AdV viremia was significantly lower with peak viremia > 10,000 copies/ml (100 vs. 17%; P = .005). CONCLUSION: AdV is associated with high all-cause mortality, especially for viremia > 10,000 copies/ml. Delaying therapy until viremia reaches AdV levels ≥10,000 copies/ml was associated with more protracted infection and poor outcomes. Larger studies are needed.

Clinical presentation and outcomes of COVID-19 following hematopoietic cell transplantation and cellular therapy.

BACKGROUND: One year into the pandemic, published data on hematopoietic cell transplantation (HCT) recipients with coronavirus disease 2019 (COVID-19) remain limited. METHODS: Single-center retrospective cohort study of adult HCT recipients with polymerase chain reaction (PCR)-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. RESULTS: Twenty-eight consecutive transplantation and cellular therapy patients (autologous, n = 12; allogeneic, n = 15; chimeric antigen receptor T-cell therapy [CAR-T], n = 1) with COVID-19 were identified. The median age was 57 years. The median time from HCT to COVID-19 diagnosis was 656 days (interquartile range [IQR], 33-1274). Patients were followed for a median of 59 days (IQR, 40-88). Among assessable patients (n = 19), 10 (53%) had documented virological clearance; median time to clearance was 34 days (range, 21-56). Out of 28, 12 (43%), 6 (21%), and 10 (36%) patients had mild, moderate, and severe/critical disease, respectively. Overall mortality was 25%, nearly identical for autologous and allogeneic HCT, and exclusively seen in hospitalized patients, older than 50 years of age with severe COVID-19. None of the patients with mild (n = 12) or moderate (n = 6) COVID-19 died whereas 7/10 patients (70%) with severe/critical COVID-19 died (P = .0001). Patients diagnosed with COVID-19 within 12 months of HCT exhibited higher mortality (57% vs 14%; P = .04). All-cause 30-day mortality (n = 4) was 14%. A higher proportion of patients who died within 30 days of COVID-19 diagnosis (3/4) were receiving ≥2 immunosuppressants, compared with patients who survived beyond 30 days after COVID-19 diagnosis (2/24; 75% vs. 8%; P = .01). CONCLUSIONS: Mortality in COVID-19 HCT patients is higher than that of the age-comparable general population and largely dependent on age, disease severity, timing from HCT, and intensity of immunosuppression.

Use of maintenance therapy and incidence of recurrent Cytomegalovirus DNAemia among allogeneic hematopoietic cell transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) infection is the most common infection following hematopoietic cell transplantation (HCT). Preemptive antiviral therapy is highly effective at halting viral replication and preventing CMV disease; however, recurrence rates after clearance of CMV DNAemia are high (50-70%). Current treatment guidelines recommend maintenance therapy after initial clearance. Yet, the effectiveness of this intervention to prevent recurrence is not well defined. OBJECTIVES: We aimed to assess the impact of maintenance therapy on the probability of recurrent CMV in allogeneic HCT recipients with early CMV reactivation. STUDY DESIGN: Sixty-six patients with an initial episode of early CMV reactivation who achieved viral clearance in response to preemptive therapy were included. We compared the incidence of recurrent CMV DNAemia in patients who received maintenance therapy vs those who underwent early discontinuation of antiviral therapy. RESULTS: Recurrence occurred in 47/64 (73%) patients, including 11/14 (79%) patients without maintenance therapy and 36/50 (72%) of patients who received maintenance therapy (P = 0.74). The propensity score adjusted risk ratio for the effect of maintenance therapy on recurrence was 0.89 (95% CI 0.64-1.25; P = 0.41). In a time to event analysis using the unweighted cohort, the 90-day probability of CMV recurrence was similar between patient groups independent of maintenance therapy administration (54% vs 64% for maintenance vs non-maintenance groups, respectively; log-rank P = 0.37). CONCLUSION: These data suggest that maintenance antiviral therapy does not reduce the incidence of CMV recurrence while off therapy and is of limited value in HCT recipients who have successfully eradicated CMV DNAemia in response to preemptive therapy. Larger studies in this area are needed.

Next-generation sequencing of microbial cell-free DNA for rapid noninvasive diagnosis of infectious diseases in immunocompromised hosts.

Background: Cell-free DNA (cfDNA) sequencing has emerged as an effective laboratory method for rapid and noninvasive diagnosis in prenatal screening testing, organ transplant rejection screening, and oncology liquid biopsies but clinical experience for use of this technology in diagnostic evaluation of infections in immunocompromised hosts is limited.  Methods: We conducted an exploratory study using next-generation sequencing (NGS) for detection of microbial cfDNA in a cohort of ten immunocompromised patients with febrile neutropenia, pneumonia or intra-abdominal infection.  Results: Pathogen identification by cfDNA NGS demonstrated positive agreement with conventional diagnostic laboratory methods in 7 (70%) cases, including patients with proven/probable invasive aspergillosis, Pneumocystis jirovecii pneumonia, Stenotrophomonas maltophilia bacteremia, Cytomegalovirus and Adenovirus viremia. NGS results were discordant in 3 (30%) cases including two patients with culture negative sepsis who had undergone hematopoietic stem cell transplant in whom cfDNA testing identified the potential etiological agent of sepsis; and one kidney transplant recipient with invasive aspergillosis who had received >6 months of antifungal therapy prior to NGS testing. Conclusion: These observations support the clinical utility of measurement of microbial cfDNA sequencing from peripheral blood for rapid noninvasive diagnosis of infections in immunocompromised hosts. Larger studies are needed.