Acute Cytokine Release Syndrome Research Articles

In situ engineering of mRNA-CAR T cells using spleen-targeted ionizable lipid nanoparticles to eliminate cancer cells

Chimeric antigen receptor (CAR) T cell therapy has implemented impressive advances in the treatment of B-cell lymphoma. However, the complex production process of CAR T cells and hindrance of solid tumor penetration remain substantial challenges. Intriguingly, cell-targeting delivery of messenger RNA (mRNA) with ionizable lipid nanoparticles (mRNA-LNPs) is able to efficiently and precisely engineer T cells and other immune cells in vivo to perform their functions. Herein, we harnessed the ionizable LNPs to encapsulate mRNA encoding anti-tyrosinase related protein 1 (TRP1) CAR (CAR-LNPs) for in vivo generation of mRNA-CAR T cells to eliminate melanoma cells. Specifically, the anti-CD3 antibody (aCD3) armed mRNA-LNPs (CD3-mRNA-LNPs) selectively targeted T cells, resulting in the production of functional and therapeutic levels of CAR T cells both ex vivo and in vivo. These CD3-CAR-LNPs engineered CAR T cells were capable of infiltrating into the solid tumor and effectively eliminating melanoma cells with high TRP1 expression, significantly hindering tumor progression. Critically, CD3–7CAR-LNPs containing mRNA encoding both CAR and interleukin-7 (IL-7) generated 7CAR T cells that secreted IL-7, thereby enhancing the activity and proliferation of both CAR T cells and other intratumoral cytotoxic T cells. Alternatively, the employment of anti-programmed cell death protein 1 antibody (aPD-1) protected mRNA-CAR T cells from exhaustion, especially in combination with CD3–7CAR-LNPs, could significantly enhance the antitumor capability of CAR T cells without causing acute cytokine release syndrome (CRS).

Azacitidine, Venetoclax and Allogeneic NK Cells in Newly Diagnosed Acute Myeloid Leukemia (ADVENT-AML): An Investigator-Initiated Multicenter Phase Ib Trial

BACKGROUND AND SIGNIFICANCE : Older/unfit patients with acute myeloid leukemia (AML) have limited treatment options. Outcomes in adverse-risk subgroups of AML are modest with CR/CRi rates of 45% to 60% and median overall survival (OS) of 5 to 12 months with current standard frontline therapy of hypomethylating agent with venetoclax (HMA-VEN).While allogeneic stem cell transplantation (allo-SCT) can significantly improve OS in AML, only 10 to 20% of older pts are able to undergo allo-SCT (Pratz et al. Blood 2019, Maiti et al. Blood 2022) Natural killer (NK) cells bridge the innate and adaptive immune system and play a major role in graft-vs-leukemia (GVL) effect responsible for the clinical benefit noted with allo-SCT. NK cell-based adoptive cellular therapies have shown good safety profiles and promising activity in AML with responses noted in 25% to 88% of patients. Furthermore, NK cells are less likely to induce graft-versus-host disease (GVHD), severe cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). We hypothesize that the combination of azacitidine, venetoclax and allogeneic NK cells will be safe and improve cure rates in AML compared to either Aza/Ven or NK cells alone. Improved clinical activity may be mediated through multiple synergistic mechanisms including reduction of disease burden by Aza/Ven, upregulation of epigenetically silenced NKG2D ligands, dual activation of extrinsic and intrinsic apoptotic cascades, mitochondrial priming of leukemia cells by venetoclax, and bypassing significant morbidity and mortality associated allo-SCT. Significance: This will be the first trial to evaluate 1) cellular therapy in the frontline setting in AML; 2) the synergy of venetoclax with adoptive NK cell therapy; and 3) Aza/Ven as a lymphodepletion strategy. The results will have significant impact on the development of cellular therapies for hematological and solid tumors. STUDY DESIGN AND METHODS: This investigator-initiated, multicenter, open-label, phase Ib study will evaluate the combination of azacitidine, venetoclax and ex vivo-expanded, off-the-shelf cryopreserved allogeneic NK cells in patients with AML (NCT05834244). Eligibility criteria: The dose escalation phase will enroll adults with relapsed or refractory AML or MDS/AML, and the dose expansion phase will enroll older/unfit pts with newly diagnosed adverse-risk AML. Eligible Pts will be ≥ 75 years, or ≥ 18 years with at least one protocol-defined comorbidity. Patients with favorable risk AML, poor end-organ function, needing immunosuppression, uncontrolled infection or CNS leukemia will be excluded. Trial design: The dose escalation phase will enroll a maximum of 12 patients at 2 dose levels to establish a recommended phase 2 dose (RP2D) using a BOIN design. The dose expansion will enroll up to 20 patients at the RP2D ( Fig. 1). Study treatment: Patients will receive Aza/Ven as standard. Two dose levels of NK cells including 0.5 x10 9 and 1 x10 9 flat dose on day 8 and 15 of the first 4 cycles will be evaluated. Subsequently, pts will continue Aza/Ven indefinitely. Objectives: The primary objective is to determine the safety of this novel triplet combination in terms of dose-limiting toxicities including acute GVHD, CRS or ICANS. Secondary objectives include overall response rate, CR/CRi by 4 cycles, rate of negative measurable residual disease, OS and relapse-free survival. Exploratory objectives include additional response and survival endpoints, the persistence of NK cells using SNP-NGS chimerism, kinetics of allorejection, remodeling of host immune microenvironment and impact on AML stem/progenitor cell hierarchies using single cell CyTOF to understand response/resistance mechanisms. Status: Trial approved by the FDA and institutional IRB. Activation planned for 2H 2023. Funding: Gateway for Cancer Research, MDACC PRIME Award, Chimeric Therapeutics, NCI Cancer Center Support Grant.

Itacitinib for Prevention of Graft-Versus-Host Disease and Cytokine Release Syndrome with T-Cell Replete Peripheral Blood Haploidentical Transplantation

Introduction: Haploidentical peripheral blood allogeneic hematopoietic cell transplantation (PB haplo-HCT) can be complicated by graft-versus-host disease (GVHD) and cytokine release syndrome (CRS). Acute GVHD rates are higher with PB grafts compared with bone marrow, affecting 35-45% of patients and outcomes are poor in steroid refractory cases. Severe CRS occurs in 10-15% of patients receiving PB haplo-HCT and is associated with high non-relapse mortality and one-year overall survival between 25-30%. As interferon-γ and IL-6 are important mediators in both acute GVHD and CRS, we hypothesized that JAK1 inhibition with itacitinib could prevent these toxicities without impairing engraftment. Here we report outcomes from our study of itacitinib with haplo-HCT (NCT03755414). Methods: Patients with AML, MDS, ALL, or NHL in remission undergoing PB haplo-HCT were treated with itacitinib 200 mg/day on days -3 through +100 (first 20 patients) or 180 (second 22 patients), followed by a taper. Myeloablative and reduced intensity conditioning were allowed. GVHD prophylaxis was tacrolimus, mycophenolate mofetil, and post-transplant cyclophosphamide. Primary outcomes were incidence of primary graft failure and incidence of grade III-IV acute GVHD. Secondary outcomes included incidence and severity of CRS, relapse, GRFS, and overall survival. Results: Forty-two patients were enrolled and underwent transplantation on study between November 2019 and December 2022, median days of follow up was 453 days (range 142-1259). The patient population had a median age of 60 years (20 - 73 years) with the majority of patients having AML (AML 60%, ALL 21%), MDS 10%, MF 5%, NHL 4%). All patients with AML, MDS, or ALL were in a complete morphologic remission, although 45% had disease by either cytogenetics, next generation sequencing, or measurable residual disease assay (flow cytometry for AML/MDS, NGS for ALL). There were no cases of grade III-IV acute GVHD. The cumulative incidence of grade II acute GVHD on day 100 was 17.3% (95% CI, 7% - 31%), day 180 was 20.5% and day 365 was 20.5%. There were no cases of severe CRS with 90% of patients having grade 1 CRS and 10% having no CRS. No anti-IL6R or steroid therapy was used. There were no cases of primary graft failure. The cumulative incidence of relapse at 1 year was 10% (95% CI, 3% to 22%) and at 2 years was 14% (95% CI, 5% to 29%). In patients who survived without relapse to day 100, the 1-year cumulative incidence of moderate or severe chronic GVHD was 5% (95% CI 1% - 17%). The refined GRFS at day +180 was 85% (95% CI 69% - 93%) and at day +365 was 79% (95% CI 62% - 89%). Overall survival at 180 days 87% (95% CI 72% - 94%) and at 1 year was 80% (95% CI 63% - 90%). Analysis of peripheral blood mononuclear cells at day +28, +60, and +100, revealed that patients on itacitinib, compared with control haplo-HCT patients, had lower numbers of CD4 and CD8 central memory T cells, lower numbers of CD4 and CD8 naïve T cells, and higher numbers of classical monocytes, nonclassical monocytes, and both myeloid and plasmacytoid dendritic cells. In itacitinib treated patients, T-cell subsets expressed lower LAG3 and PD-1 and higher TIGIT, while monocytes expressed higher HLA-DR, CD80, and CD86. Conclusions: Itacitinib with PB haplo-HCT was safe with low rates of acute and chronic GVHD, without increased risk of relapse or transplant related mortality. Severe CRS was not seen in this trial, and no anti-IL6 or steroid therapy was used. The addition of Jak inhibition to standard PtCy based GVHD prophylaxis was associated with encouraging rates of GRFS and OS on this pilot and expansion study. Patients on itacitinib have unique immune reconstitution characteristics both in terms of PBMC counts and signaling markers within subsets.

New Tocilizumab (TCZ) Dosing Guidance for T-Cell Engaging Bispecific Antibody-Related Cytokine Release Syndrome (CRS) in Patients (pts) with Relapsed/Refractory (R/R) B-Cell Non-Hodgkin Lymphoma (B-NHL): Insights from Pooled Clinical Trial Safety Experience and Quantitative Clinical Pharmacology (qCP) Analyses

Background: Mosunetuzumab (Mosun), approved for treatment of pts with R/R follicular lymphoma (FL) and ≥2 prior therapies, and glofitamab (Glofit), approved for treatment of pts with R/R diffuse large B-cell lymphoma, or large B-cell lymphoma arising from FL, and ≥2 prior therapies, are CD20xCD3 T-cell engaging bispecific antibodies that redirect T cells to eliminate B cells. CRS is a common on-target adverse event observed with bispecific antibodies and associated with exposure. TCZ, a humanized anti-interleukin-6 (IL-6) receptor, is often used for CRS management. TCZ dosing recommendations derived from CAR T-cell studies (Le et al. Oncologist 2018) may not be optimal for bispecific antibody-treated pts. Using TCZ clinical usage patterns in Mosun- or Glofit-treated pts with R/R B-NHL, qCP, and cytokine analyses, we explored a new TCZ dosing regimen for CRS management (for pts >30 kg body weight). Methods: Pooled safety data from seven Phase I/II studies evaluating Mosun or Glofit in pts with R/R B-NHL were analyzed. CRS was graded using ASTCT criteria (Lee et al. Biol Blood Marrow Transplant 2019). Modeling was used to predict TCZ concentrations (conc) and soluble IL-6 receptor (s-IL6R) occupancy over time, following administration of different TCZ dosing regimens in a subset of pts. Downstream cytokine pharmacodynamic responses (IL-6 and C-reactive protein [CRP]) were evaluated graphically post-TCZ dosing. Results: Data from 733 Mosun- and 772 Glofit-treated pts across different Mosun/Glofit dose levels were analyzed; of these, 232 (31.7%) and 427 (55.3%) pts, respectively, had ≥1 CRS event, and 36/232 (15.5%) and 140/427 (32.8%) pts received TCZ for CRS management. CRS events were mainly Grade 1/2 and occurred during the first treatment cycle. Most pts who received TCZ for CRS received ≤2 doses of TCZ overall (Mosun: 94.4%; Glofit: 84.2%) ( Table), and 1 dose of TCZ for the management of a single CRS event (Mosun: 91.7%; Glofit: 84.9%). CRS resolution was achieved within 3 days of TCZ administration in 75.0% and 66.9% of Mosun- and Glofit-treated pts, respectively. By then, a reduction in IL-6 and CRP levels was also observed. In a prior pharmacokinetic (PK) analysis of TCZ in pts with CAR T-cell-associated CRS, predicted TCZ conc after administration of 4 intravenous (IV) TCZ doses of 8 mg/kg every 8 hours (q8h) was generally below 649 μg/mL, the observed maximum conc in healthy volunteers and “safety threshold” used by the FDA (Le et al. Oncologist 2018). qCP analyses of TCZ PK and s-IL6R data from 67 pts who received TCZ for CRS management following treatment with Mosun or Glofit indicated that this TCZ regimen may exceed the safety threshold, in part because maximum TCZ conc is one-third lower in pts with CAR T-cell-induced CRS vs bispecific antibody-induced CRS. In addition, typical bispecific antibody regimens involve multiple doses compared with a single CAR T-cell infusion, with the potential for multiple CRS events requiring TCZ treatment; therefore, TCZ accumulation must be considered. qCP simulations predicted that for 1 x 8 mg/kg dose, median duration of >90% s-IL6R saturation was 28 (range: 14-28) days ( Table). Furthermore, simulations indicated that ≤2 consecutive TCZ doses q8h per CRS event and a maximum of 3 TCZ doses within a 6-week time period maintain the TCZ conc below the FDA safety threshold, while ensuring sustained s-IL6R occupancy ( Table). Conclusions: qCP results and clinical experience in Mosun and Glofit studies support a TCZ dosing regimen of ≤2 IV doses of 8 mg/kg per CRS event administered q8h, not exceeding a total of 3 doses within a 6-week period. Further improvement in CRS management and symptom resolution with additional TCZ doses is unlikely given the predicted duration of s-IL6R occupancy and observed rapid decline in systemic inflammatory markers post dosing. This proposed TCZ dosing regimen reflects TCZ usage patterns in clinical trials evaluating Mosun and Glofit, and is included in their Summaries of Product Characteristics. In patients with R/R B-NHL receiving bispecific antibody treatment, TCZ is generally suitable for management of acute CRS, and balances risk-benefit for potential scenarios involving multiple TCZ administrations for pts with CRS recurrence. This recommendation considers TCZ safety factors, the unique PK properties of TCZ in this setting and the expected duration of activity based on pharmacological modeling of target binding (s-IL6R occupancy).

Invasive Yeast Infection after Haploidentical Donor Hematopoietic Cell Transplantation Associated with Cytokine Release Syndrome

The use of haploidentical donor hematopoietic cell transplantation (haploHCT) has expanded, but recent reports raise concern for increased rates of infectious complications. The incidence and risk factors for invasive fungal disease (IFD) after haploHCT have not been well elucidated. This study aimed to evaluate the incidence and risk factors for IFD after haploHCT. The identification of key risk factors will permit targeted prevention measures and may explain elevated risk for other infectious complications after haploHCT. This single-center retrospective study included all adults undergoing haploHCT between May 2011 and May 2021 (n=205). The 30-day and 1-year cumulative incidences of proven or probable IFD and 1-year nonrelapse mortality (NRM) were assessed. Secondary analyses evaluated risk factors for invasive yeast infection (IYI) using univariate and multivariable Cox regression models. Twenty-nine patients (14%) developed IFD following haploHCT. Nineteen (9.3%) developed IYI in the first year, 13 of which occurred early, with a 30-day cumulative incidence of 6.3% (95% confidence interval [CI], 2.9% to 9.6%) and increased NRM in patients with IYI (53.9% versus 10.9%). The majority of yeast isolates (17 of 20; 85%) were fluconazole- susceptible. The incidence of IYI in the first 30 days after haploHCT was 10% in the 110 patients (54%) who developed cytokine release syndrome (CRS) and 21% in the 29 patients (14%) who received tocilizumab. On multivariable analysis, acute myelogenous leukemia (hazard ratio [HR], 6.24; 95% CI, 1.66 to 23.37; P=.007) and CRS (HR, 4.65; 95% CI, 1.00 to 21.58; P=.049) were associated with an increased risk of early IYI after haploHCT. CRS after haploHCT is common and is associated with increased risk of early IYI. The identification of CRS as a risk factor for IYI raises questions about its potential association with other infections after haploHCT. Recognition of key risk factors for infection may permit the development of individualized strategies for prevention and intervention and minimize potential side effects.

A Single-Arm, Open-Label, Pilot Study of the JAK1 Selective Inhibitor Itacitinib for the Prophylaxis of Graft-Versus-Host Disease and Cytokine Release Syndrome in T-Cell Replete Haploidentical Peripheral Blood Hematopoietic Cell Transplantation

Introduction:Haploidentical peripheral blood allogeneic hematopoietic cell transplantation (PB haplo-HCT) can be complicated by graft-versus-host disease (GVHD) and cytokine release syndrome (CRS). Acute GVHD rates are higher with PB grafts compared with bone marrow, affecting 35-45% of patients and outcomes are poor in steroid refractory cases. Severe CRS occurs in 10-15% of patients receiving PB haplo-HCT and is associated with high non-relapse mortality and dismal one year overall survival between 25-30%. As interferon-γ and IL-6 are important mediators in both acute GVHD and CRS, we hypothesized that JAK1 inhibition with itacitinib could prevent these toxicities without impairing engraftment. Here we report the clinical outcomes from our pilot study of itacitinib with haplo-HCT (NCT03755414).Methods:Patients with AML, ALL, or NHL in remission undergoing PB haplo-HCT were treated with itacitinib 200 mg/day on days -3 through +100, followed by a taper. Myeloablative and reduced intensity conditioning were allowed. GVHD prophylaxis was tacrolimus, mycophenolate mofetil, and post-transplant cyclophosphamide. Primary outcomes were incidence of primary graft failure and incidence of grade III-IV acute GVHD. Secondary outcomes included incidence and severity of CRS (graded by Lee criteria). Peripheral blood and serum samples were banked prior to conditioning and on days -1, 1, 3, 7, 14, 28, 60, 100, end of treatment, and time of diagnosis of acute GVHD. Matched control samples were collected from patients undergoing haplo-HCT off clinical trials. Correlative studies include flow cytometry (FACS) with five 28-color panels for cellular subsets, mass cytometry (CyTOF) with 40-colors for intracellular signaling events, single cell RNA sequencing, and serum cytokine and chemokine measurements.Results:Twenty of a planned 20 patients completed enrollment and underwent haplo-HCT between 11/2019 and 3/2021. Median age at transplant was 49 (21-74). Diagnoses were AML (13), ALL (5) and NHL (2). Median follow up is 319 days, with 18/20 beyond 180 days. There were no cases of engraftment failure with short median times to neutrophil (14 days, range 12-20) and platelet (14 days, range 7-54) engraftment (historical 16 and 25 days, respectively). There were no cases of grade III-IV acute GVHD. The incidence of grade II acute GVHD on day 100 was 15%. Two patients developed grade I-II skin acute GVHD during itacitinib taper and responded to resumption of a higher dose. There were no cases of extensive chronic GVHD. There were no cases of severe CRS (historical rate 17%), with 90% of patients having grade 1 CRS and 10% having no CRS. Furthermore, no anti-IL6R or steroid therapy was used. Overall survival at day 180 was 90% (95% CI 75-100%) by Kaplan-Meier estimate. Incidence of relapse at 180 days was 5.5% (95% CI 0-15.6%). Refined GVHD and relapse-free survival at 180 days was 83% (95% CI 68-100%). All patients had full donor engraftment and >95% chimerism at day 100.FACS and CyTOF have been performed and analyzed for the day 28 time point from 14 patients and four controls. Flow cytometry revealed no difference in cell subset numbers between controls and patient samples. CyTOF revealed differences in intracellular signaling molecules between itacitinib and control patients - including higher Ki-67, pNF-κB, and Caspase3 in controls. Phospho-Stat1 and pStat3 were lower CD4 T subsets. FACS and CyTOF at remaining time points, single cell RNA sequencing, and serum cytokine and chemokine measurements are underway and will be presented at the ASH 2021 meeting.Conclusions:Itacitinib with PB haplo-HCT was safe with no engraftment failure and prompt engraftment. Rates of acute and chronic GVHD were low, without increased risk of relapse or transplant related mortality. Severe CRS was not seen in this trial, and no anti-IL6 or steroid therapy was used. Flow cytometry demonstrated comparable immune reconstitution in terms of cell lineage and number between treated patients and controls. Mass cytometry revealed lower Ki-67, pNF-κB, and caspase3 levels, among other markers, which suggest lower immune cell activity, proliferation, and apoptosis. An extension cohort of 20 additional patients is enrolling. Multi-platform correlative studies are underway, comparing samples from haplo-HCT patients treated with and without itacitinib. [Display omitted] DisclosuresUy: Astellas: Honoraria, Speakers Bureau; Novartis: Consultancy; Agios: Consultancy; Jazz: Consultancy; Genentech: Consultancy; AbbVie: Consultancy; GlaxoSmithKline: Consultancy; Macrogenics: Research Funding. Ghobadi: Atara: Consultancy; Amgen: Consultancy, Research Funding; Wugen: Consultancy; Celgene: Consultancy; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding. Jacoby: Abbvie: Research Funding; Jazz: Research Funding. Pusic: Syndax: Other: Advisory Board. Schroeder: Equillium Inc: Honoraria; Janssen: Honoraria; Sanofi Genzyme: Honoraria.

Janus Kinase Inhibitors and Cell Therapy.

Cellular therapies such as allogeneic hematopoietic stem cell transplantation (HSCT) and immune-effector cell therapy (IECT) continue to have a critical role in the treatment of patients with high risk malignancies and hematologic conditions. These therapies are also associated with inflammatory conditions such as graft-versus-host disease (GVHD) and cytokine release syndrome (CRS) which contribute significantly to the morbidity and mortality associated with these therapies. Recent advances in our understanding of the immunological mechanisms that underly GVHD and CRS highlight an important role for Janus kinases (JAK). JAK pathways are important for the signaling of several cytokines and are involved in the activation and proliferation of several immune cell subsets. In this review, we provide an overview of the preclinical and clinical evidence supporting the use of JAK inhibitors for acute and chronic GVHD and CRS.

Beyond Cytokine Storm: Optimizing Treatment Strategies to Target the Complex Interplay between CAR Mediated Inflammatory Response, Disseminated Intravascular Coagulation and Macrophage Activation Syndrome

Background: Cytokine release syndrome (CRS) is a well described, non-specific toxicity of CAR therapy caused by high-level immune activation. Generally, CRS starts within a week of CAR-T cell infusion, is typically self-limited, and mitigation strategies utilizing tocilizumab (anti-IL6 receptor antibody) and/or corticosteroids are rapidly effective. Despite initial improvement, delayed manifestations including disseminated intravascular coagulation (DIC) and macrophage activation syndrome (MAS) may occur in some for whom CAR mediated inflammatory responses continue to evolve. To improve upon the safety profile of CAR therapy, we report on our experience with DIC and MAS.Design: We report on the toxicity profile of the first 30 children and young adults with relapsed/refractory CD22+ ALL treated on our phase I dose escalation anti-CD22 CAR therapy. All had routine monitoring of cytokines, fibrinogen, D-Dimer, PT/INR, PTT and CBC. Following observations of clinically significant DIC, we prospectively evaluated markers of activated coagulation, including: thrombomodulin, E-selectin, s-VCAM, v-ICAM, P-selectin, prothrombin fragment 1 + 2, tissue factor, and PAI-1. Markers for MAS, including ferritin, triglycerides and soluble IL2R were monitored, as well as immunohistochemical staining for hemophagocytosis on the bone marrow aspirate/biopsy.Results: From December 2014 to July 2017, 30 patients with ALL were treated at 3 dose levels. CRS was seen in 24/30 (80%), which was grade 1-2 in all, except for one grade 4. Eight of 24 (33%) with CRS developed DIC, which was grade 2 (no bleeding) in 3 patients and grade 3 (with bleeding) in 5 patients. Bleeding complications were primarily mucosal and included diffuse alveolar hemorrhage, epistaxis, hematuria, subconjunctival hemorrhage and petechiae/purpura that appeared disproportionate to the platelet count and typically occurred after resolution of acute CRS. Correspondingly, morphologic evaluation revealed hypogranular/agranular platelets seen in 16 of 20 patients (confirmed by electron microscopy in one), of whom 7 had DIC, suggesting an acquired platelet function defect; such patients received higher transfusion support. In those with DIC, PT/INR/PTT and D-Dimer rose with onset of CRS. Fibrinogen, initially elevated with the onset of CRS, fell precipitously with resolution of fever. At the time of clinically evident DIC, in 8 of 12 evaluable subjects, P-selectin values rose at least 50%, on average 17.6 days after CAR-T infusion and in 11 of 12 evaluable subjects, endothelial markers rose and peaked 2 weeks after CAR-T infusion (mean 15.2 days). Treatment of DIC was primarily supportive; methylprednisolone, starting at 0.5-1 mg/kg was initiated in patients with active bleeding, and continued q6-8 hours until stabilization. Resolution of DIC typically coincided with decrease in ferritin, suggesting an inflammatory mediated coagulopathy. Accordingly, patients with DIC also had statistically significantly higher ferritin (median 361,585 v 14,349, p<0.0001) IFN-g, IL-1b, IL-6, IL-8, IL-10 and MIP-1a (p<0.01 for all) than in those without DIC, mimicking elevations seen in MAS. Further supporting the link to MAS, 3 of 4 patients with DIC had soluble IL2R levels > 5-fold x the upper limit of normal at 2 weeks post CAR therapy. Additionally, one patient with DIC had active hemophagocytosis at the 1 month evaluation (Figure), which in the constellation of hepatic transaminitis, cytopenias and hyperferritinemia led to a diagnosis of MAS. Treatment with single agent anakinra, an IL-1 receptor antagonist, initiated as a steroid-sparing agent, was well tolerated and led to full resolution of hemophagocytosis; importantly, it did not impede ongoing CAR response, with clearance of all minimal residual disease from the one month to the two-month restaging time point.Conclusion: An intricate relationship exists between the initial inflammatory CRS, and later complications of DIC and MAS potentially induced by CAR T related inflammation. Although steroids and supportive care measures may stabilize DIC, cytokine profiles, which include elevated IL-1b, can assist when choosing targeted, steroid-sparing therapies such as anakinra. Future directions will include exploring the link between inflammation, DIC, and MAS and optimizing targeted anti-inflammatory strategies earlier in the treatment course to prevent serious complications. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

S1068 Transaminases Are Potential Biomarkers of Disease Severity in Coronavirus Disease-2019 (COVID-19) Patients

INTRODUCTION: Considering the rapid spread of SARS-CoV2, the clinical implications of hepatic manifestations of COVID-19 in the U.S. population requires analysis. METHODS: We retrospectively reviewed all adult patients with COVID-19 admitted to our facility between March 13th and May 1st, 2020. Patients were divided into two groups based on the presence or absence of transaminitis at presentation. All patients with elevated alanine transaminase (ALT) or aspartate transaminase (AST) > 1 x upper limit of normal were considered to have transaminitis. Kruskal-Wallis and Pearson's chi-square tests were used to compare median of continuous and categorical variables, respectively. Multivariate logistic regression analysis was performed to identify predictors of mechanical ventilation (MV), cytokine release syndrome (CRS), and mortality after adjusting for baseline variables. RESULTS: A total of 84 patients were included in the analysis; 44 (52.3%) patients had transaminitis on admission. There was a higher number of male patients with transaminitis than without transaminitis (79.5% vs. 42.5%, P = 0.0001) (Table 1). Baseline demographics and laboratory parameters were similar among patients with and without transaminitis (Table 2). Patients with transaminitis had significantly higher risk of developing acute hypoxic respiratory failure, shock, CRS, and deep vein thrombosis as demonstrated in Table 3A. On a multivariate analysis, presence of transaminitis on admission ((adjusted odds ratio (aOR): 5.69, 95% CI, 1.47–21.99, P = 0.01) was associated with an increased risk of developing cytokine release syndrome (CRS). Transaminitis on admission and elevated total bilirubin during hospitalization were associated with an increased need for MV (aOR of 6.17, 95% CI, 1.49–25.44, P = 0.02 and aOR of 7.29, 95% CI, 1.73–30.75, P = 0.007, respectively). Elevated AST on admission (aOR of 13.41, 95% CI, 1.08–165.69, P = 0.04) and elevated total bilirubin during hospitalization (aOR of 82.68, 95% CI, 1.67–4074.8, P = 0.02) were independently associated with an increased risk of mortality in COVID-19 patients (Table 3B). CONCLUSION: COVID-19 patients with transaminitis had higher risk of requiring MV and developing CRS. Patients with elevated AST on admission and elevated total bilirubin during hospitalization had higher mortality. As such, elevated transaminases seemed to correlate with worsening disease severity and could be potential markers for risk stratification in the western population.Table 1Table 2Table 3

Incidence and Management of Effusions during CD19-Directed Chimeric Antigen Receptor (CAR) T-Cell Receptor Therapy in B-Cell Lymphoma: A Single Institution Experience

<h3>Background</h3> In patients with lymphoma, third space fluid accumulations may develop or worsen during cytokine release syndrome (CRS) associated with chimeric antigen receptor (CAR) T-cell therapy. Pre-existing symptomatic pleural effusions were excluded by the ZUMA-1 trial of axicabtagene ciloleucel (axi-cel) for large B cell lymphoma (LBCL) and variants. The optimal management of effusions that develop before or after axi-cel infusion in LBCL is unknown. <h3>Methods</h3> We performed a single center retrospective study evaluating 148 patients receiving CD19 CAR T-cell therapy for LBCL between 05/2015 and 09/2019. We identified all patients who developed pleural, pericardial and peritoneal effusions before (pre-CAR-T) or during the first 30 days after CAR T-cell infusion (post-CAR-T). Clinically relevant effusions were considered symptomatic based upon physician documentation. <h3>Results</h3> Total effusions and symptomatic effusions were noted in 24% (36/148) and 18% (27/148) of patients, respectively. Among 27 patients with symptomatic effusions, 59% (16/27) were pre-CAR-T effusions, 52% (14/27) persisted after day 30, and 44% (12/27) were malignant effusions. Overall, 67% of symptomatic effusions (18/27) were managed with diuretics, 44% (12/27) with a therapeutic thoracentesis or paracentesis and 33% (9/27) were observed with only supplemental oxygen provided. Six patients required pleural or abdominal catheters with a median indwelling duration of 54 (range, 29, 202) days, although 2 of these patients passed away with these indwelling catheters. Among symptomatic effusions developing only post-CAR-T (n=11), time to onset of effusion was median of 5 (range, 2-11) days and none of these patients required interventional drainage. Table 1 differentiates between effusions based on whether they were present (n = 19) or not (n = 17) prior to CAR T cell infusion. <h3>Conclusions</h3> Nearly half of all effusions diagnosed in patients receiving CAR T cell therapy develop after infusion but most can be medically managed. Patients with pre-CAR-T effusions may require procedural drainage or indwelling catheters, as these effusions may persist beyond the acute CRS period.

Sequential CD19- and Bcma-Specific Chimeric Antigen Receptor T Cell Treatment for RRMM: Report from a Single Center Study

Background: Relapsed and/or refractory multiple myeloma (RRMM) has a very poor prognosis, especially for chinese patients with limited therapeutic options. Chimeric antigen receptor transduced T cells (CARTs) had been approved to be one of the rescue strategies for malignant B cell hematological tumors. CARTs targeting B-Cell Maturation Antigen (BCMA) were effective against RRMM in recent published clinical studies. CD19 is expressed by B cells before terminal differentiation into plasma cells and is associated with the enhancement of tumor-propagating and drug-resistance properties of myeloma. Thus, CD19 is also a potential therapeutic target. To our knowledge, we firstly designed the clinical study to evaluate the safety and efficacy of sequential infusion of CD19 and BCMA-Specific CARTs for RRMM patients (pts) (NCT 03196414). Our initial results showed this stragety had substantial anti-myeloma activity and well tolerated toxicities, which had been released at the 59th ASH meeting. Here, we will report the latest clinical data of a total of 28 RRMM patients receiving combined autologous CARTs infusion. Methods: Human T cells were collected from autologous peripheral blood mononuclear cells (PBSC). CART production was performed by the Unicar-Therapy Bio-medicine Technology Company (Shanghai, China). In this trial, RRMM pts firstly receive FC regimen as lymphodepleting conditioning , then were infused into CART-19 (1×107/kg on day 0) and CART-BCMA (total dose range: 2-6.8×107/kg) cells as split-dose infusions (40% on day 1 and 60% on day 2). After one month from CARTs infusion, some pts were adminstrated IMiDs for maintence therapy after hematopoietic recovery, including oral thalidomide 50mg/d or lenalidomide 10mg/d. This trial design and observation was seen in Blood,2017,130(Suppl.):506.The median follow-up time was 16 (3-28) months. Results: By January 2019, 28 pts were enrolled in this clinical trial. Among them, 23 (82.1%) pts were males and 5 (17.9%) pts were females. The median age was 57.5 (range: 42-69) years old. All pts were resistant to proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), or both. These pts had received an average of 3 (2-8) lines of therapy prior to enrollment. The most common adverse event of CART therapy was acute cytokine release syndrome (CRS), which occurred in 28 pts (100%). 19 pts (67.9%) were evaluated grade 1-2 CRS. 7 pts (25.0%) were evaluated grade 3 CRS, and 2 pts (7.1%) were grade 4. High-grade CRS was associated with elevated levels of IL-6, IFNγ, IL-10 and CRP, especially IL-6 upgradation to thousands of times the baseline. Other toxicities within two weeks of CARTs infusion included fatigue (n=28; 100%), cytopenia (n=28; 100%), anemia (n=28; 100%), prolonged APTT (n=23; 82.1%), elevated creatinine (n=13; 46.4%), gastrointestinal reaction(n=9; 32.1%), elevated transaminase (n=9; 32.1%). Notably, one patient (CRS grade 4) developed grade 4 CRES who exhibited generalized seizure. But this life-threatening complication was quickly relieved after corticosteroids and sodium valproate administration. Two pts (7.1%) had HLH/MAS. No fatal or severe adverse events emerged after two weeks following the infusion. Chronic side effects included chronic diarrhea, hematocytopenia, mild infection, grade ≤2 bilirubin and/or transaminase elevation, hypogammaglobulinemia, etc. No treatment related mortality occurred in this group of pts. Among the 28 pts who completed the CARTs infusion, 27 pts were monitored at predetermined time points and one patient lost follow-up. The overall response rate was 92.6%, and 88.9% of the pts were above PR. 11 pts (40.7%) were CR or sCR, 8 pts (29.6%) were VGPR, 5 pts (18.5%) were PR and one (3.7%) was MR. The remaining 2 pts, one (3.7%) was evaluated as SD and another (3.7%) was PD. 4 pts died from myeloma progression during the follow-up. Of those pts, the median PFS was 8 months. The median OS was 16 months. Conclusions: Combined sequential administration of CART-19 and CART-BCMA cells can be manufactured from heavily-treated MM pts, and could elicit sustained remission for RRMM pts. Toxicities can be well tolerated. CARTs early expansion and persistence in vivo post infusion may be predictive of clinical outcome. How to prolong the survival time of CARTs in vivo is one of the subjects worth studying in the future. Disclosures No relevant conflicts of interest to declare.

Early administration of tocilizumab (Toci) for the prevention of grade 4 cytokine release syndrome (CRS) after CD19-directed CAR T-cell therapy (CTL019)

Background & Aim The most common side effect of CD19-directed CAR-T cell therapy is CRS. IL-6 blockade by toci typically results in rapid resolution of severe CRS in CTL019 treated pts; however, the ideal timing of toci remains unclear. Pts with high tumor burden (TB; defined as ≥40% marrow blasts) are at high risk for severe CRS. We hypothesized that preemptive toci administration early in the course of CRS in pts with high TB might decrease acute CRS severity without compromising efficacy. Methods, Results & Conclusion MTD We conducted a two-cohort, open-label study of the timing of toci on CTL019-associated CRS. Pts were 1-24 yo with CD19-expressing relapsed or refractory B-cell acute lymphoblastic leukemia (r/r B-ALL). CTL019 was manufactured at the UPenn Cell and Vaccine Production Facility. Enrolled pts were assigned to high (≥ 40%) or low ( 38.5 C measured twice in 24 hours (“early toci”) and subsequently treated per standard CRS algorithm. Primary endpoint: frequency of gr4 CRS (Penn scale) in ≤5/15 pts. Secondary endpoints: D28 tumor response, remission duration, additional toxicities. RES 78 pts were screened, all were enrolled. 65 pts were evaluable for analysis at data cutoff. 15 pts were assigned to HTBC, 50 pts to LTBC and all were infused with CTL019 (median dose 5.0 × 106 [range 5.6 × 105-3.9 × 107] CAR+ T cells/kg). The overall rate of gr4 CRS was 9% (27% in the HTBC, 4% in the LTBC, Table 1). The overall rate of gr1-4 CRS was 72% (100% in the HTBC, 64% in the LTBC). One pt in the HTBC died from CNS hemorrhage after gr4 CRS. All patients in the HTBC received the early toci intervention. The overall rate of gr3 and 4 CRS was lower than in two prior studies of CTL019 therapy in pediatric r/r B-ALL (18% vs 42% in CHP959 and 48% in ELIANA). The ORR at day 28 follow-up was 97% (87% HTBC, 100% LTBC, with 71% CR and 26% CRi, Table 2). CONC We defined clincially meaningful reduction in severe CRS if ≤5/15 subjects had gr4 CRS in the HTBC; this a priori defined primary end-point was met. Early administration of toci targeted to pts with high TB may reduce the incidence of severe CRS while maintaining excellent efficacy of CTL019 therapy. TB remains a major predictor of toxicity. Longer follow-up is ongoing to assess impact on duration of remission.

Acute acalculous cholecystitis: A new safety risk for patients with MS treated with alemtuzumab.

To evaluate acute acalculous cholecystitis (AAC) as a potential safety risk for patients treated with alemtuzumab. The Food and Drug Administration Adverse Event Reporting System and the medical literature were searched for cases of AAC in conjunction with alemtuzumab for all clinical indications. Eight spontaneously reported cases meeting the case definition of AAC in close temporal association with alemtuzumab use were identified. Based on established criteria within the Food and Drug Administration Division of Pharmacovigilance for causality assessment, 4 cases were assessed as probable while 4 were possible. All cases occurred in patients with relapsing-remitting multiple sclerosis. Seven of the 8 cases presented with AAC during or shortly after alemtuzumab treatment, thereby suggesting an acute cytokine release syndrome as a putative pathogenic mechanism. The cases identified in this review differ from the typical AAC cases described in the medical literature based on female preponderance, lack of concurrent critical illnesses, inconsistent presence of other risk factors, and resolution with conservative treatment in the majority of cases. AAC represents a new and potentially life-threatening adverse event associated with alemtuzumab use in relapsing-remitting multiple sclerosis. In cases seen to date, early and conservative treatment resulted in good clinical outcome, although the natural history of AAC in this population without critical illness is not well defined. Awareness of this safety risk by general and specialty neurologists is important for prompt recognition and optimal management.

Durable remissions with BCMA-specific chimeric antigen receptor (CAR)-modified T cells in patients with refractory/relapsed multiple myeloma.

LBA3001 Background: Chimeric antigen receptor engineered T cell (CAR-T) is a novel immunotherapeutic approach for cancer treatment and has been clinically validated in the treatment of acute lymphoblastic leukemia (ALL). Here we report an encouraging breakthrough of treating multiple myeloma (MM) using a CAR-T designated LCAR-B38M CAR-T, which targets principally BCMA. Methods: A single arm clinical trial was conducted to assess safety and efficacy of this approach. A total of 19 patients with refractory/relapsed multiple myeloma were included in the trial. The median number of infused cells was 4.7 (0.6 ~ 7.0) × 10e6/ kg. The median follow-up times was 208 (62 ~ 321) days. Results: Among the 19 patients who completed the infusion, 7 patients were monitored for a period of more than 6 months. Six out of the 7 achieved complete remission (CR) and minimal residual disease (MRD)-negative status. The 12 patients who were followed up for less than 6 months met near CR criteria of modified EBMT criteria for various degrees of positive immunofixation. All these effects were observed with a progressive decrease of M-protein and thus expected to eventually meet CR criteria. In the most recent follow-up examination, all 18 survived patients were determined to be free of myeloma-related biochemical and hematologic abnormalities. One of the most common adverse event of CAR-T therapy is acute cytokine release syndrome (CRS). This was observed in 14 (74%) patients who received treatment. Among these 14 patients there were 9 cases of grade 1, 2 cases of grade 2, 1 case of grade 3, and 1 case of grade 4 patient who recovered after treatments. Conclusions: A 100% objective response rate (ORR) to LCAR-B38M CAR-T cells was observed in refractory/relapsed myeloma patients. 18 out of 19 (95%) patients reached CR or near CR status without a single event of relapse in a median follow-up of 6 months. The majority (14) of the patients experienced mild or manageable CRS, and the rest (5) were even free of diagnosable CRS. Based on the encouraging safety and efficacy outcomes, we believe that our LCAR-B38M CAR-T cell therapy is an innovative and highly effective treatment for multiple myeloma.

Macrophages sense pathogens via DNA motifs: induction of tumor necrosis factor-alpha-mediated shock.

Cell surface components of pathogens, such as lipopolysaccharide (LPS), are an important signal for receptor-mediated activation of immune cells. Here we demonstrate that DNA of gram-positive and gram-negative bacteria or certain synthetic oligonucleotides displaying unmethylated CpG-motifs can trigger macrophages in vitro to induce nuclear translocation of nuclear factor-kappa B, accumulate tumor necrosis factor (TNF)-alpha mRNA and release large amounts of TNF-alpha. In vivo these events culminate in acute cytokine-release syndrome which includes systemic but transient accumulation of TNF-alpha. D-Galactosamine (DGalN)-sensitized mice succumb to lethal toxic shock due to macrophage-derived TNF-alpha resulting in fulminant apoptosis of liver cells. LPS and a specific oligonucleotide synergized in vivo as measured by TNF-alpha-release, suggesting that macrophages integrate the respective signals. The ability of macrophages to discriminate and to respond to bacterial DNA with acute release of pro-inflammatory cytokines may point out an important and as yet unappreciated sensing mechanism for foreign DNA.