Adoptive Cell Transfer of Allogeneic Epstein–Barr Virus-Specific T Lymphocytes for Treatment of Refractory EBV-Associated Posttransplant Smooth Muscle Tumors: A Case Report

Posttransplant smooth muscle tumors (PTSMTs) are rare Epstein–Barr virus (EBV)-associated neoplasms, mostly occurring after solid organ transplantation. Current therapeutic strategies include surgery and reduction of immunosuppressive medication. We describe for the first time a novel treatment approach for PTSMT by adoptive cell transfer (ACT) of EBV-specific T cells to a 20-year-old patient with a medical history of cardiac transplantation, posttransplant lymphoproliferative disease, and multilocular PTSMT. During ACT, mild cytokine release syndrome occurred, while no unexpected safety signals were recorded. We observed in vivo expansion of EBV-specific T cells and reduction of EBV viremia. Best response was stable disease after 4 months with reduction of EBV viremia and normalization of lactate dehydrogenase levels. ACT with EBV-specific T cells may be a safe and efficacious therapeutic option for PTSMT that warrants further exploration.

Sex Differences in EBV Viremia after Haplo-HSCT Imply Sex Bias during Immune Reconstitution

Objective: Posttransplant infection is common and tough to deal, patients after HSCT rely on immune reconstitution for protection. We desperately need a deeper understanding of how the system works to help the patients overcome the infection. Method: This study analyzed the disease course of EBV viremia after haplo-HSCT, as well as the laboratory testing data. The sex bias during immune reconstitution was manifested by comparing the outcomes between male and female patients, Results: 236 patients received haplo-HSCT in 2013 in our center, at a median follow up of 5 years, among whom 78 patients underwent EBV infection. The incidence of EBV viremia after transplantation is 33.1% in total, with a significant difference between men and women (40.0% and 26.7% respectively, p=0.034). Men tended to have earlier onset time (14-434d after HSCT) and longer duration (7-70d) than women (17-592d after HSCT, 7-30d). Both the initial and peak viral load were higher in men than in women (initial viral load＞10 4/ml: men 6.52% vs. women 3.13%, peak viral load＞10 5/ml: men 8.70% vs. women 3.13%). To explain this phenomenon, we analyzed the laboratory testing data on 30d and 60d after HSCT. And we found that male patients had higher plasma levels of immunoglobulin M on 60d after HSCT if infected by EBV, referring to more robust induction of innate immune (p=0.033). By contrast, female patients had significantly increased CD4+ T cell during EBV infection, representing more robust activation of adaptive immune (p=0.019). Conclusion: These findings provide a possible explanation for the observed sex biases in EBV viremia after haplo-HSCT, and provide an important basis for the recognition of immune reconstitution, furthermore, raise concern of the development of a sex-based approach to the treatment and care of male and female patients with infection after HSCT. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Impaired Antibody-Dependent Cellular Cytotoxicity in a Spanish Cohort of Patients With COVID-19 Admitted to the ICU

SARS-CoV-2 infection causes COVID-19, ranging from mild to critical disease in symptomatic subjects. It is essential to better understand the immunologic responses occurring in patients with the most severe outcomes. In this study, parameters related to the humoral immune response elicited against SARS-CoV-2 were analysed in 61 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centres in Madrid, Spain, during the first pandemic peak between April and June 2020. Subjects were allocated as mild patients without hospitalization, severe patients hospitalized or critical patients requiring ICU assistance. Critical patients showed significantly enhanced levels of B cells with memory and plasmablast phenotypes, as well as higher levels of antibodies against SARS-CoV-2 with neutralization ability, which were particularly increased in male gender. Despite all this, antibody-dependent cell-mediated cytotoxicity was defective in these individuals. Besides, patients with critical COVID-19 also showed increased IgG levels against herpesvirus such as CMV, EBV, HSV-1 and VZV, as well as detectable CMV and EBV viremia in plasma. Altogether, these results suggest an enhanced but ineffectual immune response in patients with critical COVID-19 that allowed latent herpesvirus reactivation. These findings should be considered during the clinical management of these patients due to the potential contribution to the most severe disease during SARS-CoV-2 infection.

The effect of Epstein – Barr Virus Viremia on the Progression to Severe COVID-19

BackgroundCoronavirus disease 2019 (COVID-19) can reactivate several latent viruses. Epstein–Barr virus (EBV) is a latent virus that is frequently reactivated in patients with critical illnesses. Recently, a high incidence of viremia has been reported in patients with severe COVID-19. However, it is unclear whether EBV viremia is the result of the severity of COVID-19 or if it affects the severity of COVID-19. Therefore, we conducted a cohort study to evaluate the effects of EBV on the progression of COVID-19.MethodsWe compared the incidence of EBV viremia between the COVID-19 and non-COVID-19 groups. Simplified Acute Physiology Score (SAPS) II and lymphocyte subsets were analyzed in patients with COVID-19. We also observed that patients with COVID-19 with EBV viremia progressed to severe pneumonia more often than those without EBV viremia.ResultsTwo hundred and nine patients with COVID-19 were compared with the control (non-COVID-19) group. The incidence of EBV viremia was lower in the COVID-19 group than in the non-COVID-19 group (17.1% vs. 26.8%, P=0.034). In the subgroup analysis of the COVID-19 group, the EBV-positive group patients had more severe COVID-19 infection than the EBV-negative group (SAPS II, 22.3 vs. 17.4%; P=0.002). However, progression to moderate or severe pneumonia in patients with mild COVID-19 was rather high in the EBV-negative group (not statistically significant), contrary to our expectations.ConclusionsAlthough the severity of COVID-19 may affect EBV viremia, there is no evidence that EBV viremia is a factor that exacerbates pneumonia in patients with early COVID-19. The effect of EBV viremia on prolonged organizing pneumonia should be further studied.

Clinical Experience of Tabelecleucel in Patients with Life-Threatening Complications of Epstein-Barr Virus Viremia

Background Epstein-Barr virus (EBV) viremia - a condition of persistent active (vs latent) EBV infection - can be associated with a variety of life-threatening disorders. One such disorder is chronic active EBV (CAEBV), a type of primary immunodeficiency associated with high mortality rates. Another entity is EBV-driven (EBV+) hemophagocytic lymphohistiocytosis (HLH), characterized by a hyperactive immune response with elevated cytokines. Both can be associated with multi-organ dysfunction and failure. In addition, EBV viremia may be associated with complications following allogeneic hematopoietic cell transplantation (HCT) or can herald relapse of EBV+ malignancies. Tabelecleucel, an investigational off-the-shelf, allogeneic EBV-specific T-cell immunotherapy, has previously shown clinical activity in patients with EBV+ post-transplant lymphoproliferative disease (PTLD), EBV+ PTLD with central nervous system involvement and EBV+ leiomyosarcoma (Prockop S et al, JCI 2020; Kurlander et al, ESMO 2018) and is a potential therapy for CAEBV, HLH or EBVviremia in other life-threatening settings since it may control the EBV-based stimuli underlying these distinct diseases (Icheva V et al, J Clin Oncol 2013). Here, we report data in patients with complications of EBV viremia treated with tabelecleucel in an expanded access study (NCT02822495) within two non-overlapping protocols (EAP-201 [2016-2018] and EAP-901 [2018-present]). Methods Eligible patients received tabelecleucel at ~2 x 106 cells/kg/dose on Days 1, 8 and 15, with laboratory assessments on Day ~28 of each 5-week cycle. EAP-201 enrolled patients with persistent EBV viremia (defined as serum EBV DNA assays showing detectable EBV viral load at least 4 weeks apart and known or suspected immunodeficiency or history of prior EBV+ malignancy) as well as patients with EBV+ HLH. EAP-901 includes patients with persistent EBV viremia and known or suspected immunodeficiency. Patients who did not respond could switch to tabelecleucel with a different human leukocyte antigen (HLA) restriction (restriction switch). In EAP-201, response criteria were based on reduction in EBV viral load and/or on HLH response criteria (Table 1). As EAP-901 is intended to provide compassionate access to tabelecleucel, limited patient data are collected compared with EAP-201; however, response is assessed by the investigators based on reduction in EBV viral load to determine whether an HLA restriction switch is needed. In both protocols, patients continued treatment until unacceptable toxicity, maximal response (2 consecutive complete responses [CR] or 3 partial responses [PR]), or up to 4 different HLA restrictions. Both protocols collected serious AEs (SAEs). Results Patient characteristics, treatment exposure, and responses are reported in Table 1; 5 patients with EBV viremia participated in EAP-201 and 4 in EAP-901. Objective response rates were 80% (n=4/5) for EAP-201 and 50% (n=2/4) for EAP-901. For EAP-201, the median time to first response for the 4 patients who responded was 1.7 (min 1.0, max 4.7) months, and for EAP-901 it was approximately 1 month for both patients who responded. Table 2 summarizes the treatment-emergent SAEs (TESAEs) observed with both protocols. EAP-901 reported a fatal SAE of chronic hepatic failure that was assessed as unrelated to treatment. One patient in EAP-901 experienced a grade 3 TESAE of facial nerve disorder that was assessed as possibly related to tabelecleucel; there were no other fatal or treatment-related TESAEs reported in either protocol, and no safety concern has emerged for this patient population. Conclusions Tabelecleucel was well tolerated and showed evidence of clinical activity in patients with life-threatening EBV viremia. Based on these results, further clinical investigation of tabelecleucel in patients with HLH or CAEBV is planned within an upcoming study (ATA129-EBV-205). Disclosures Ghobadi: Amgen: Consultancy, Research Funding. Stiff:CRISPR: Consultancy; Gamida-Cell: Research Funding; Atara Biotherapeutics: Research Funding; Amgen: Research Funding; Incyte: Research Funding; Takeda: Research Funding; Macrogenics: Research Funding; Eisai: Research Funding. Reshef:Kite: Consultancy, Research Funding; Atara Biotherapeutics: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy; Magenta: Consultancy; Incyte: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Pfizer: Consultancy; Celgene: Research Funding; Shire: Research Funding. Navarro:Atara Biotherapeutics: Current Employment, Current equity holder in publicly-traded company. Gamelin:Atara Biotherapeutics: Current Employment, Current equity holder in publicly-traded company. Dinavahi:Atara Biotherapeutics: Current Employment, Current equity holder in publicly-traded company. Sun:Atara Biotherapeutics: Current Employment, Current equity holder in publicly-traded company. Guzman-Becerra:Atara Biotherapeutics: Current Employment, Current equity holder in publicly-traded company. Prockop:Mesoblast: Consultancy, Research Funding; Atara Biotherapeutics: Research Funding; Jasper Pharmaceuticals: Research Funding; Memorial Sloan Kettering: Patents & Royalties: IP related to the development of third party viral specific T cells with all of my interests assigned to MSK.

Association Between Cytomegalovirus and Epstein-Barr Virus Viremia And Human Immunodeficiency Virus DNA Levels in the Reservoir of Kenyan Infants Receiving Antiretroviral Therapy

Identifying determinants of human immunodeficiency virus (HIV) reservoir levels may inform novel viral eradication strategies. Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) coinfections were assessed as predictors of HIV proviral DNA level in 26 HIV RNA–suppressed Kenyan children starting antiretroviral therapy before 7 months of age. Earlier acquisition of CMV and EBV and higher cumulative burden of systemic EBV DNA viremia were each associated with higher HIV DNA level in the reservoir after 24 months of antiretroviral therapy, independent of HIV RNA levels over time. These data suggest that delaying or containing CMV and EBV viremia may be novel strategies to limit HIV reservoir formation.

Epstein–Barr Virus and Cytomegalovirus Reactivation in Patients with COVID-19

BackgroundSince first report of COVID-19 in December 2019, it has spread to a pandemic, making many deaths. Dysfunction of immune function is considered as one of the reasons for high mortality. Epstein–Barr virus (EBV) and Cytomegalovirus (CMV) reactivation in severe patients is thought to be related to immune dysfunction but is not yet known in COVID-19. MethodsWe conducted EBV and CMV real-time PCR confirmed patients with COVID-19 who were admitted to our hospitals.ResultsOf the 61 COVID-19 patients, nine EBV and two CMV viremia were found. The group with EBV viremia had a higher probability of progressing to severe COVID-19 infection than the group without, but it was not statistically significant. One out of two people with CMV viremia died and one survived after Extracorporeal Membrane Oxygenation use. ConclusionsOur study suggests immune dysfunction in COVID-19, and further research is needed on the role of EBV/CMV in COVID-19.

Pre-Transplant MRD Negativity Predicts Favorable Outcomes of CAR-T Therapy Followed By Haploidentical HSCT for Relapsed/Refractory Acute Lymphoblastic Leukemia: A Multi-Center Retrospective Study

Patients with relapsed/refractory acute lymphoblastic leukemia (R/R ALL) usually have a very poor prognosis and an expected survival of less than 6 months.The complete remission (CR) rates in the setting of the first salvage chemotherapy are about 30% to 46% and these rates drop sharply to 18% to 25% after the second salvage chemotherapy. Chimeric antigen receptor T cells (CAR-T) can induce high CR rates of 70-95% (MRD negative CR rates of 60-90%) among patients with R/R ALL. Howeve, relapse after CAR-T treatment is supposed a main obstacle for long-term outcome. Some reports have described relapse rates of 20-70% when the follow-up was long enough. It remains controversial whether these patients should receive allo-HSCT after CAR-T treatment or not. We designed a multi-center retrospective study to assess the efficacy and safety profiles of CAR-T therapy followed by haplo-HSCT. A total of 31 patients treated with CAR-T therapy followed by haplo-HSCT were included. Eleven patients who progressed to MRD positive or relapse subsequently underwent haplo-HSCT (MRD positive or relapse group) and the rest 20 patients with MRD negativity received haplo-HSCT (MRD negative group). The median time from CAR-T infusion to haplo-HSCT was 83 (range 62-114) days. After a median follow-up period of 288 (range 189-554) days post-transplantation, the 100-day cumulative incidence (CI) of grade III~IV aGVHD was 0% and 10.5% in the MRD positive or relapse group and MRD negative group, respectively (P>0.05)(Figure 1a). One and 2-year CIs of cGVHD requiring systemic steroid therapy were 52.3% and 31.1% (P>0.05), 52.3% and 39.7% (P>0.05) in the MRD positive or relapse group and MRD negative group, respectively(Figure 1b).The 1-year cumulative incidence of CMV viremia was 90.9%, 68.4% and 77.8% in the MRD positive or relapse group, MRD negative group and the whole population respectively (P>0.05). The 2-year cumulative incidence of CMV viremia was 90.9%, 78.9% and 85.2% in the MRD positive or relapse group, MRD negative group and the whole population respectively (P>0.05). The 1-year cumulative incidence of EBV viremia was 90.9%, 79.6% and 84.2% in the MRD positive or relapse group, MRD negative group and the whole population, respectively (P>0.05). And the 2-year cumulative incidence of EBV viremia was 90.9%, 89.8% and 89.5% in the MRD negative or relapse group, MRD negative group and the whole population, respectively (P>0.05). Onset of CMV and EBV viremia occurred in 33.5 (26.3-50.0) days and 44.0 (28.5-57.0) days after transplantation in 24 and 25 patients, respectively. Median peak CMV DNA and EBV DNA load were 1.5X104 (2.6X103-3.4X104) copies/ml and 2.2X104 (1.1X104, 4.1X104) copies/ml, respectively. One and 2-year CIs of relapse were 84.8% and 6.7% (p<0.001), 100% and 15.2% (p<0.01%) in the MRD positive or relapse group and MRD negative group, respectively (Figure 1d). One-year GVHD and relapse free survival (GRFS), leukemia free survival (LFS) and overall survival (OS) in the MRD positive or relapse group and MRD negative group were 18.2% and 58.9% (P=0.024), 15.2% and 93.3% (P<0.001), 43.6% and 100% (P=0.002), respectively (Figure 1f). Two-year GRFS, LFS and OS in the MRD positive or relapse group and MRD negative group were 0% and 50.5% (P=0.007), 0% and 84.8% (P<0.001), 14.5% and 83.3% (P<0.001), respectively (Figure 1c,e,f). No patient died of therapy-associated complications. Relapse or MRD positivity at the time of haplo-HSCT is the only independent factor associated with poor LFS [hazard ratio (HR): 23.6, 95% confidence interval (CI): 2.78-201.63, P=0.004] and OS [HR: 10.4, 95% CI: 1.12-94.45, P= 0.037]. In conclusion, our trial provided data to illustrate the safety and efficacy profiles of a novel combining therapeutic strategy against R/R ALL by using the combination of CAR-T cells for re-induction followed by haplo-HSCT for consolidation. We confirmed that achieving pre-transplant MRD negativity after CAR-T treatment is a suitable basis for haplo-HSCT. Our study results imply that CAR-T therapy followed by haplo-HSCT could further improve LFS and OS without increasing risks of treatment-related toxicity in such a previously heavily treated population. Further evaluation is needed from larger scale studies with a more homogeneous patient population and longer follow-ups. Figure 1 Disclosures Blaise: Jazz Pharmaceuticals: Honoraria; Sanofi: Honoraria; Molmed: Consultancy, Honoraria; Pierre Fabre medicaments: Honoraria. Mohty:Jazz Pharmaceuticals: Honoraria, Research Funding.

Results of a Multicentre, Randomized, Controlled Open-Label Study on the Use of Anti-T-Lymphocyte Globulin (ATLG) and Rituximab for Immunomodulation of Graft-Versus-Host Disease (GvHD) and Graft Failure (GF) in Patients with Non-Malignant Disorders

BACKGROUND: Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) is increasingly used to treat a wide range of non-malignant disorders. However, the optimal strategy to be employed for GvHD prevention remains a matter of debate. In particular, the use of ATLG for the prevention of immune-mediated complications in patients transplanted from a matched-related donor (MRD) is still controversial. In the matched unrelated donor (MUD) setting, there is retrospective evidence that Rituximab used as prophylaxis of EBV viremia may protect from acute GvHD (aGvHD) development, but the clinical benefit of pre-transplant Rituximab has never been assessed in prospective randomized studies. METHODS: We conducted a multicentre, randomized, open-label, trial (NCT01810926) in 5 Italian centres enrolling patients with non-malignant haematological and inherited metabolic disorders transplanted from either a MRD or a MUD, selected using high-resolution typing for HLA-class I/II loci and stringent criteria of HLA-compatibility (>9/10). All patients received the same myeloablative regimen consisting of Treosulfan, Thiotepa and Fludarabine. Enrolled patients were randomized (1:1) to receive either standard or intensified GvHD prophylaxis. Cyclosporine-A plus short-term methotrexate was the standard GvHD prophylaxis in MRD HSCT recipients. In the experimental arm, patients were additionally given ATLG (Grafalon®, Neovii, 5 mg/kg/day on day -4,-3, and -2). In patients transplanted from a MUD, standard GvHD prophylaxis consisted of Cyclosporine-A plus short-term methotrexate and ATLG (10 mg/kg on day -4,-3 and-2). In the experimental arm, patients were additionally given Rituximab 200 mg/sq on day -1 (Mabthera®, Roche). In MRD group randomization was stratified by disease (hemoglobinopathies vs. other conditions) and in the MUD group by center. For patients given MRD HSCT, the primary end-point was the probability of survival (SUR) free from: a) primary and secondary GF, b) grade II-IV aGvHD, c) chronic GvHD (cGvHD), d) death, whichever occurred first. For patients transplanted from a MUD, the primary end-point was the SUR probability free from: a) grade II-IV aGvHD, b) EBV viremia (>1,000 copies of viral DNA/ml whole blood), whichever occurred first. Secondary endpoint was overall SUR (OS). Statistical analyses were conducted according to intention-to-treat. FINDINGS: Between August 2011 and February 2018, 126 patients were enrolled. Patient and disease characteristics by randomized treatment are shown in Table 1. Median age at HSCT was 6.1 years in the MRD group (range 0.8-38) and 4.9 years in the MUD group (range 0.9-20.7). Median follow-up was 3.6 years. Among the 51 MRD-HSCT recipients, 25 were randomly assigned to the ATLG group and 26 to the NO-ATLG group. No death and no cases of grade II-IV aGvHD were observed in either of the two randomization arms. Two GF occurred in each of the two arms, while 1 and 2 cases of cGvHD occurred in the ATLG and NO-ATLG groups, respectively. Consequently, no statistically significant difference in the probability of SUR without events was observed (p=0.75) and the 3-years estimates (±SE) were 86.9%±7.1% vs. 83.8%±7.5%, respectively. In the MUD setting, 38 patients were allocated in the Rituximab group and 37 in the NO-Rituximab group. Although no statistically significant difference in OS (p=0.21) was observed between the two arms (3-years estimates: 94.1%±4.1% for Rituximab, 85.7%±5.9% for No-Rituximab), patients receiving Rituximab had a better probability of SUR without events (73.0%±7.3% vs 26.5%±7.3%, respectively; p=0.0002), entirely due to a lower incidence of EBV viremia. One case of fatal post-transplant lymphoproliferative disorder was observed in the No-Rituximab arm. Eight patients developed grade II-IV aGvHD in each of the two arms. No patient has persistent dependence on ivIG replacement therapy. CONCLUSIONS Our data indicate that, in patients with non-malignant disorders given a MRD HSCT, the addition of ATLG does not confer any advantage in the prevention of both acute and chronic GvHD, as well as of GF. In MUD-HSCT recipients, the administration of a fixed dose of pre-transplant Rituximab as part of the conditioning regimen does not affect the risk of aGvHD and transplant-related mortality, while it significantly reduces the incidence of episodes of EBV-viremia, without impairing B-cell recovery. Disclosures Algeri: Bluebird bio: Consultancy, Honoraria; Miltenyi: Honoraria; Atara Biotherapeutics: Consultancy, Honoraria. Merli:Novartis: Honoraria; Sobi: Consultancy; Amgen: Honoraria; Bellicum: Consultancy. Locatelli:Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; bluebird bio: Consultancy; Miltenyi: Honoraria; Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees.