Management Of Cytokine Release Syndrome Research Articles

Anticytokine Therapy and Corticosteroids for Cytokine Release Syndrome and for Neurotoxicity Following T-Cell Engager or CAR T-Cell Therapy

What Is the Issue? Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) are the most common toxicities secondary to T-cell engager or chimeric antigen receptor (CAR) T-cell therapy. The US FDA and Health Canada approved tocilizumab, an anti-interleukin-6 receptor antagonist, for the management of severe or life-threatening cases of CRS. Corticosteroids also play an important role in CRS management and are the mainstay of ICANS management. Decision-makers are interested in understanding the use of anticytokine drugs (i.e., tocilizumab, anakinra, siltuximab) and/or corticosteroids in the management of CRS and ICANS following T-cell engager or CAR T-cell therapy. What Did We Do? We identified and summarized the literature comparing the clinical effectiveness and safety of anticytokine therapy and/or corticosteroids with alternative care or treatment as usual for treating and preventing of CRS and ICANS. We also searched for evidence-based recommendations for the use of anticytokine therapy and/or corticosteroids to treat and prevent CRS and ICANS. A research information specialist conducted a literature search of peer-reviewed and grey literature sources published between January 1, 2019 and February 26, 2024 for CRS; and between January 1, 2019 and March 4, 2024 for ICANS. One reviewer screened citations for inclusion based on predefined criteria, critically appraised the included studies, and narratively summarized the findings. What Did We Find? This report presents evidence-based findings on 3 retrospective chart review studies, 2 prospective cohort studies, and 4 consensus guidelines. Limited and low-quality clinical evidence from studies with a high risk of bias suggested that early use of tocilizumab or corticosteroids, or prophylactic use of tocilizumab or anakinra may reduce the risk of a high-grade CRS without a negative impact on neurotoxicity or immunotherapy treatment outcomes. The included guidelines recommend the use of tocilizumab for treatment of higher-grade CRS, or for treatment of grade 1 CRS if symptoms persist for 3 days or more. Corticosteroids could be added in conjunction if there is no improvement or persistent symptoms after tocilizumab therapy. For the management of ICANS in the absence of concurrent CRS, supportive care is the preferred treatment option for grade 1 ICANS, while corticosteroids are recommended for the management of grade 2 to 4 ICANS. In the presence of concurrent CRS, guidelines recommend tocilizumab therapy as per management of CRS, and corticosteroids should be continued until improvement to grade 1. We did not identify any clinical evidence regarding the clinical efficacy and safety of anticytokine therapy and/or corticosteroids for treatment of CRS and ICANS compared with alternative treatment or treatment as usual. We also did not identify any guidelines for the use of prophylactic anticytokine therapy, corticosteroids, or both for the prevention of CRS and ICANS. What Does This Mean? Despite limited and low-quality evidence, the findings suggest some potential benefits of prophylactic or early use of anticytokine therapy and corticosteroids for the management of immunotherapy-related toxicities. Guidelines offer guidance on the management of CRS, ICANS and other less common toxicities related to immunotherapy based on the available low-quality evidence. When using the clinical evidence and recommendations summarized in this report to inform decisions, decision-makers should consider that the evidence is limited and of low quality. To improve the certainty of findings, there is a need for more robust prospective clinical trials with larger sample sizes, and lower risk of bias.

Current and emerging pharmacotherapies for cytokine release syndrome, neurotoxicity, and hemophagocytic lymphohistiocytosis-like syndrome due to CAR T cell therapy.

Chimeric antigen receptor (CAR) T cells have revolutionized treatment of multiple hematologic malignancies. Engineered cellular therapies now offer similar hope to transform management of solid tumors and autoimmune disease. However, toxicities can be serious and often require hospitalization. We review the two chief toxicities of CAR T therapy, cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), and the rarer immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome. We discuss treatment paradigms and promising future pharmacologic strategies. Literature and therapies reviewed were identified by PubMed search, cited references therein, and review of registered trials. Management of CRS and ICANS has improved, aided by consensus definitions and guidelines that facilitate recognition and timely intervention. Further data will define optimal timing of tocilizumab and corticosteroids, current foundations of management. Pathophysiologic understanding has inspired off-label use of IL-1 receptor antagonism, IFNγ and IL-6 neutralizing antibodies, and janus kinase inhibitors, with data emerging from ongoing clinical trials. Further strategies to reduce toxicities include novel pharmacologic targets and safety features engineered into CAR T cells themselves. As these potentially curative therapies are used earlier in oncologic therapy and even in non-oncologic indications, effective accessible strategies to manage toxicities are critical.

Abstract 6734: Preclinical impact of pretreatment with CRS mitigation agents on pharmacodynamic response to TAK-500, a systemically delivered CCR2-targeted STING agonist iADC

Abstract Background: Stimulator of interferon genes (STING) agonists elicit potent innate immune enhancement and mobilize robust adaptive immune responses. Given the potential risk of immunotoxicity from associated cytokine release due to STING agonist treatment, there is a need to identify mitigation strategies that minimize immune-related toxicity while offering a therapeutic window for STING-mediated anti-tumor effects. This strategy is particularly relevant for myeloid-targeted immunotherapies, as cytokine release syndrome (CRS) can be myeloid cell-mediated. We utilized preclinical models to evaluate the pharmacological impact of pretreatment with agents routinely used for management of CRS in advance of delivering TAK-500, a novel, systemic, immune-cell directed STING agonist antibody drug conjugate (iADC) that selectively targets CCR2+ myeloid cells. Methods: Dexamethasone and anti-IL-6R antibodies were tested at clinically relevant doses 1 hour prior to treatment with TAK-500 or mTAK-500, a murine surrogate, to study immunomodulatory and anti-tumor effects in preclinical models. Induction of innate and adaptive immune responses and cytokine release was evaluated in human, ex vivo, and in tumor-bearing mouse models to characterize potential impact of premedication strategies on drug pharmacology and anti-tumor efficacy. Results: TAK-500 triggered dose-dependent monocyte activation and cytokine secretion ex vivo. Monocyte activation was minimally impacted by dexamethasone or anti-IL-6R pretreatment. Suppression of IL-6 and IFN-ƴ and increase in IL-10 were observed following dexamethasone pretreatment, whereas anti-IL-6R maintained a more proinflammatory milieu. In syngeneic mouse models, pretreatment with dexamethasone and anti-mouse IL-6R had minimal impact on mTAK-500 anti-tumor efficacy. Key pharmacodynamic effects, including innate immune cell activation in periphery and tumor-draining lymph node and intratumoral CD8+ T cell accumulation, were minimally impacted by either pretreatment agent. Serum cytokine analyses demonstrated suppression of IL-6, IFN-ƴ and increases in IL-10 with dexamethasone, but not with anti-IL-6R, similar to ex vivo findings. Conclusion: Premedication of TAK-500 and mTAK-500 with dexamethasone or anti-IL-6R antibodies does not substantially impact STING-mediated innate immune activation, mobilization of adaptive immune responses or anti-tumor efficacy, despite altered cytokine profiles compared to (m)TAK-500 without premedication. Clinically, these premedication strategies have been effective in mitigating immunotherapy-associated CRS with T cell therapeutics, and here resulted in maintained anti-tumor activity when used in combination with TAK-500, suggesting a viable potential strategy for mitigation of STING-induced immunotoxicities in patients. Citation Format: Emily Rosentrater, Michelle L. Ganno, Tiquella Hatten, Henry Mack, Arjun Reddy Bollampalli, Dong Mei Zhang, Alex Parent, Jeffrey Raizer, Richard C. Gregory, Neil Lineberry, Vicky Appleman. Preclinical impact of pretreatment with CRS mitigation agents on pharmacodynamic response to TAK-500, a systemically delivered CCR2-targeted STING agonist iADC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6734.

Multi-centers experience using therapeutic plasma exchange for corticosteroid/tocilizumab-refractory cytokine release syndrome following CAR-T therapy

The chimeric antigen receptor T (CAR-T) cell therapy significantly enhances the prognosis of various hematologic malignancies; however, the systemic expansion of CAR-T cells also gives rise to severe cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS). Despite the successful application of corticosteroids and tocilizumab in alleviating severe CRS in most patients, there are still individuals who experience life-threatening CRS without responding to the aforementioned therapies. In our retrospective cohort, we conducted an analysis of clinical and laboratory parameters, including inflammatory cytokines, in 17 patients from three centers who underwent therapeutic plasma exchange (TPE) for refractory CRS with or without ICANS following CAR-T products treatment. Our findings demonstrate a significant improvement in both clinical symptoms and laboratory parameters subsequent to TPE treatment. The rapid decrease in temperature and levels of inflammatory indexes indicates the remarkable scavenging efficacy of TPE against cytokine storm following CAR-T therapy. In conclusion, TPE may serve as a valuable and safe adjunct to corticosteroids and tocilizumab in the management of severe CRS resulting from CAR-T cell infusion. We eagerly await further prospective studies to validate this finding.

Management of Patients Undergoing CAR-T Cell Therapy in Germany

Introduction: Chimeric antigen receptor positive T cell (CAR-T cell) treatment became standard therapy for relapsed or refractory hematologic malignancies, such as non-Hodgkin’s lymphoma and multiple myeloma. Owing to the rapidly progressing field of CAR-T cell therapy and the lack of generally accepted treatment guidelines, we hypothesized significant differences between centers in the prevention, diagnosis, and management of short- and long-term complications. Methods: To capture the current CAR-T cell management among German centers to determine the medical need and specific areas for future clinical research, the DAG-HSZT (Deutsche Arbeitsgemeinschaft für Hämatopoetische Stammzelltransplantation und Zelluläre Therapie; German Working Group for Hematopoietic Stem Cell Transplantation and Cellular Therapy) performed a survey among 26 German CAR-T cell centers. Results: We received answers from 17 centers (65%). The survey documents the relevance of evidence in the CAR-T cell field with a homogeneity of practice in areas with existing clinical evidence. In contrast, in areas with no – or low quality – clinical evidence, we identified significant variety in management in between the centers: management of cytokine release syndrome, immune effector cell-related neurotoxicity syndrome, IgG substitution, autologous stem cell backups, anti-infective prophylaxis, and vaccinations. Conclusion: The results indicate the urgent need for better harmonization of supportive care in CAR-T cell therapies including clinical research to improve clinical outcome.

Outpatient Management of CAR-T and Teclistamab for Patients with Lymphoma and Multiple Myeloma

Background: Patients (pts) receiving FDA-approved chimeric antigen receptor T-cell (CAR-T) therapy or Bispecific antibody Teclistamab (Tec) are commonly managed in the inpatient setting given the common adverse events such as cytokine release syndrome (CRS) and immune cell-associated neurotoxicity syndrome ICANS. We have previously reported that hospital-based outpatient (HBO) management of pts receiving CAR-T is feasible and safe (Bansal et al, ASH2022). In 2023, HBO management at our institution began incorporating home health visits and management of grade 1 CRS in outpatient setting for select pts receiving standard of care (SOC) CAR-T. Here, we report outcomes of our updated practice. Methods: We retrospectively analyzed medical records and remote monitoring data of adult pts who received SOC CAR-T or Tec between 10/2020 and 7/2023 at Mayo Clinic, Rochester under an IRB approved protocol. Results: In 3/2023, pts deemed to be low risk for severe CRS (fever onset >= 3 days from infusion, CRP<100) received HBO management for grade 1 CRS, including outpatient administration of tocilizumab. If CRS improved or resolved, outpatient monitoring was continued. If CRS persisted within the observation period on HBO, pts were admitted. Recurrent CRS after the first episode were all managed inpatient. Nine pts met these criteria for HBO CRS management and their outcomes were compared to those who received initial inpatient (INPT) CRS management (INPT, n=17) during the same timeframe, as well as the outcome of 164 pts who had CRS management INPT prior to our practice change (Table 1). Two-third of the pts with initial management of CRS outpatient did not require hospitalization. Median time to hospitalization trended later than those managed inpatient at the onset of CRS. The duration of hospitalization was comparable for all pts admitted between initial HBO and INPT CRS management. However with fewer admissions in the initial CRS HBO group, the average hospitalization days (LOS) per patient treated for that group was lower compared to initial INPT CRS management. Data on additional pts will be presented at ASH. In 1/2023, pts on RPM with no ongoing CRS symptoms, no language barriers, and no compliance concerns received home health visits during weeks 3 and 4 post CAR-T infusion in place of clinic visits on HBO. Home health visit team communicated with HBO staff to review assessment and plan. Changes in HBO utilization will be presented. Finally, 24 pts received 223 Tec infusions on HBO. Median age was 66 years, 15 (61%) were males, 9 (38%) had high risk cytogenetics. The median prior lines of therapy was 5. Among these pts, 220/223 (99%) doses were performed on HBO and 204/220 (93%) infusions never required admission for management. Twenty pts enrolled in RPM (Figure 1). An average of 2 alerts were generated per patient during the 2 week period and median time from infusion to alert was 1.5 days. Majority of alerts were resolved over a phone call and only 13/114 (11%) alerts required a physician visit/hospital admission. Of the 16 Tec infusions resulting in admission, 4/16 (25%) required re-admission resulting in a total of 20 hospitalizations. Admissions mostly occurred during step-up dosing (18/20; 90%). Most common reason for first admission was fever (13/16, 85%) and median time to admission was 1 day from infusion. Median LOS was 1.5 days (range, 0-12). In terms of CRS, majority were Grade 1 (12/13, 93%) which were managed with steroids (dexamethasone/ prednisone) alone. One patient had CRS grade 4 event, in the setting of concurrent decompensation during dialysis, and was treated with steroids, tocilizumab, vasopressor, CRRT, thoracentesis, intubation and mechanical ventilation. The rate of second CRS event after management of first CRS with steroid (dexamethasone/ prednisone) was 15% (2/13). These second CRS episodes also resolved with steroid alone. Data on additional pts receiving Tec will be presented at ASH. Conclusion: Our data showed that additional advances in outpatient practice, including initial outpatient management of CRS and outpatient administration of Tec step up dosing are feasible, safe and reduce hospital resource utilization.

Chimeric Antigen Receptor T-Cell Therapy in Elderly Patients with Relapsed or Refractory Large B-Cell Lymphoma: A Multicenter Study

Background: Anti-CD19 chimeric antigen receptor T-cell (CART) therapy is a standard of care in patients (pts) with relapsed or refractory (RR) large B-cell lymphoma (LBCL). However, it remains underutilized in elderly pts due to limited efficacy and safety data. We therefore evaluated real world outcomes of CART in such pts. Methods: Seven academic centers participated in this retrospective study. Pts aged ≥65 years with RR LBCL who received a commercial CART product were included. Baseline characteristics, treatment data, CART toxicity, and clinical outcomes were collected. Progression-free survival (PFS; time from infusion to disease progression or death) and overall survival (OS; time from infusion to death from any cause) were analyzed using Kaplan-Meier method. Cumulative incidences of non-relapse mortality (NRM) and disease relapse/progression were estimated accounting for competing risks. Statistical analyses were performed in JMP v15 and XLSTAT v2022.1.2. Results: 209 pts were identified. Baseline characteristics and treatment pattern are shown in Table. Median age at infusion was 71 years (range 65-89), and 25 (12%) were ≥80 years. 131 (63%) were male, 188 (90%) were white, and 27 (13%) had ECOG PS of ≥2. The median HCT-CI was 1 (range 0-6), and 39 (22%) pts had a score of ≥3. 165 (84%) had stage III-IV disease, 131 (70%) had extranodal involvement, 24 (18%) had bulky disease, and 24 (11%) had high grade B-cell lymphoma (HGBL; double- or triple-hit lymphoma, n=15; HGBL, NOS, n=9). The median number of prior lines of therapy was 2 (range 1-8), and 99 (48%) pts had ≥3 prior lines of therapy, 45 (22%) had prior bendamustine, and 44 (21%) had prior stem cell transplant (SCT; auto-SCT, n=41; allo-SCT, n=2; both auto- and allo-SCT, n=1). Bridging therapy was given to 100 (52%) pts; among those, 57 had chemotherapy, 20 had radiotherapy, 6 had both chemotherapy and radiotherapy, 10 had lenalidomide-based regimen, and 7 had CD20 antibody and/or corticosteroids. Axicabtagene ciloleucel (axi-cel) was most frequently used (63%, n=131), followed by lisocabtagene maraleucel (liso-cel) (24%, n=49) and tisagenlecleucel (tisa-cel) (13%, n=27). Cytokine release syndrome (CRS) occurred in 75% of pts, and a minority (6%) had grade ≥3. Immune effector cell associated neurotoxicity syndrome (ICANS) occurred in 55%, and 29% had grade ≥3. The management of CRS and ICANS included corticosteroids in 101 (49%) pts, tocilizumab in 116 (56%) pts, and other biologic agents (anakinra, siltuximab, basiliximab) in 8 (4%) pts. Day 30 response was evaluable in 195 pts with an objective response rate (ORR) of 84%, and a complete response rate (CR) of 52%. 82% of the responders continued to have a response at 3 month follow up. The ORR/CR rates were 86%/53% for axi-cel, 64%/44% for tisa-cel, and 89%/52% for liso-cel, respectively. At a median follow up of 19.1 months (95% CI 16.1-23.6) after infusion, the median PFS was 6.7 months (95% CI 5.1-11.5), with 6- and 12-month PFS rates of 54% (95% CI 47-61) and 43% (95% CI 35-50), respectively. The median OS was 16.5 months (95% CI 13.2-26.7), and the 6-and 12-month OS rates were 70% (95% CI 64-77) and 61% (95% CI 54-68), respectively. The NRM rate was 17% (95% CI 11-24) at 1 year, primarily due to infections including 5 COVID-19 related deaths. In univariate analysis, ECOG PS ≥2, bulky disease, elevated LDH, and the need for bridging therapy were associated with inferior PFS and OS. No significant difference in PFS and OS was seen based on age at infusion with a median PFS of 6.4 vs 9.6 vs 6.4 vs 6.0 months ( P=0.93) (Figure) and OS of 16.4 vs 19.2 vs 28.5 vs 12.7 months ( P=0.85) in age groups ≥65-69 vs ≥70-74 vs ≥75-79 vs ≥80-89. In addition, there was no statistically significant difference in PFS and OS based on type of CART with a median PFS of 6.4 vs 5.6 vs 12.7 months ( P=0.16) and OS of 15.1 vs vs 16.1 vs NR months ( P=0.24) in pts treated with axi-cel vs tisa-cel vs liso-cel. Conclusions: In this large multicenter study of elderly pts with RR LBCL, CART therapy demonstrated favorable efficacy and safety profile comparable to that in pivotal registration trials. Survival outcomes appeared similar regardless of patient age, including those aged ≥80 years, and type of CART product used. Similar to younger pts, high tumor burden and poor performance status at CART infusion were associated with inferior survival. This analysis confirms that older pts should not be excluded from receiving CART therapy solely due to chronological age.

Day +3/Day 0 Ferritin Ratio: A Simple Point-of-Care Index Predictive of Severe Immune Effector Cell-Associated Neurotoxicity Syndrome after CD19 CAR T-Cell Therapy

Introduction: Chimeric antigen receptor (CAR) T-cell therapy is transforming the management of patients with relapsed/refractory (R/R) B- and plasma-cell malignancies. However, a major limitation of CAR T-cell therapy is the development of severe, sometimes life-threatening, toxicities such as immune effector cell-associated neurotoxicity (ICANS) and cytokine release syndrome (CRS). While the management of CRS has dramatically improved with the early use of tocilizumab and corticosteroids, how to best predict and treat ICANS remains poorly understood, with up to 30% of patients developing severe ICANS after CD19 CAR T-cell therapy. Since we had previously observed features overlapping with hemophagocytosis lymphohistiocytosis in patients with severe CRS and ICANS, we hypothesized that the early kinetics of ferritin and soluble IL-2 receptor alpha [sIL-2Rα] post infusion could predict the development of severe ICANS. Methods: We retrospectively analyzed data from 195 patients with R/R B-cell malignancies previously treated on a phase I/II clinical trial (NCT01865617) of an investigational defined 1:1 CD8+:CD4+ composition CD19 CAR-T product (JCAR014; training set). CRS and ICANS severity were graded using Lee 2014 and CTCAE 4.03 criteria, respectively. Logistic regression was used to predict the occurrence of severe ICANS. Ferritin was measured using an enzyme immunoassay. sIL-2Rα was measured using Luminex®. Goodness of fit was assessed using the Akaike information criterion (AIC). Independent test set included 203 patients treated at our center with the standard-of-care CD19 CAR T-cell products axicabtagene or lisocabatagene maraleucel. Discrimination and calibration were assessed in both the training and test set. Results: In the training set (n=195), median age was 55 (range: 20-76). Disease type was as follows: acute lymphoblastic leukemia, n=64 (32.8%); B-cell non-Hodgkin lymphoma, n=82 (42.1%); chronic lymphocytic leukemia, n= 47 (24.1%). We observed any grade and grade ≥3 CRS in 134 (68.7%) and 27 (13.8%), respectively, and any grade and grade ≥3 ICANS in 72 (38.8%) and 37 (19.0%), respectively. Longitudinal analyses of serum ferritin (Figure 1) and sIL-2Rα values using locally estimated scatterplot smoothing suggested that the rate of increase of both analytes was markedly higher in patients with grade ≥3 ICANS compared to grade 0-2 ICANS. We applied univariate logistic regression to estimate the association between serum ferritin levels at early timepoints, select ratios of ferritin and sIL-2Rα values, and the occurrence of severe ICANS. The strongest association was observed between the ferritin day +3/day 0 ratio and severe ICANS (OR per log10 increase, 175; 95% CI, 19.1-2668; p < 0.001). We could further improve our model by modeling the ferritin day +3/day 0 ratio with a restricted cubic spline to allow for non-linear effects (unsplined model, AIC = 129, C-index, 0.74; splined model, AIC = 127, C-index, 0.78). Ferritin day +3/day 0 ratios of 3, 5, and 10 were associated with an 81%, 95%, and 99% probability of grade ≥3 ICANS, respectively (Figure 2). The splined model was associated with near-perfect calibration corrected for optimism using bootstrapping. We next evaluated the predictive ability of the ferritin day +3/day 0 ratio to predict severe ICANS in our independent test set. Predictions in the test set based on our splined model retained good discriminative ability with a C-index of 0.64, although with suboptimal calibration. In a refitted logistic regression model in the test set, the ferritin day +3/day 0 ratio remained strongly associated with the development of severe ICANS (OR = 18.8 per log10 increase, 95%CI, 2.48-142.01, p = 0.004). Conclusion: We validated the ability of a simple point-of-care index (day +3/day 0 ferritin ratio) to predict the development of severe ICANS after CD19 CAR T-cell therapy in our training and test set. Since serum ferritin levels can be quickly measured by most clinical laboratories, the day +3/day 0 ferritin ratio could become a practical and useful tool for practitioners taking care of CAR T-cell patients. The early identification of patients at high risk of developing severe ICANS days prior to symptoms onset could enable the evaluation of targeted prophylactic interventions in future clinical trials. We plan to refine our modeling approach to further improve the calibration in test set.

Real-World Incidence, Characteristics and Management of Cytokine Release Syndrome Induced By Chimeric Antigen Receptor T-Cell Therapy across Hematologic Malignancies

Background: Cytokine release syndrome (CRS) is a potentially life-threatening, supraphysiologic response following immunotherapy resulting in the activation or engagement of endogenous or infused T cells and/or other immune effector cells. CRS occurs with varying frequency and severity, depending on the underlying disease and immunotherapy used, such as chimeric antigen receptor T-cell (CAR-T) therapy or off-the-shelf T-cell engaging bispecific antibodies. Limited research exists on the diagnosis and management of CRS in the real world. This study describes the real-world incidence, severity and clinical management of CRS induced by commercially available CAR-T therapies for diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL) and multiple myeloma (MM). Methods: Real-world data (RWD) were obtained from the Flatiron Health, US, nationwide electronic health record (EHR)-derived, de-identified database of cancer patients within a network comprised primarily of community cancer practices. The Flatiron Health network also includes practices designated as academic sites by the National Cancer Institute; however, relative proportions of community/academic practices may vary depending on the study cohort. Data as of August 31, 2022, on CAR-T therapy, clinical characteristics and disease outcomes specific to CAR-T therapy, as well as CRS and its clinical management, were abstracted from unstructured documents in EHRs (in addition to routinely available structured data), in a cohort of patients receiving commercial CAR-T therapy. Specifically, data for CRS including treatments and resolution were abstracted based on explicit mention of and attribution to CRS in charts. Results: Table 1 summarizes data by indication. Incidence of CRS ranged from 56% (104/185) in DLBCL to 72% (66/92) in MCL. Excluding categories with small numbers of cases (<15), CRS incidence also varied by individual CAR-T therapy and underlying indication and ranged from 35% for idecabtagene vicleucel in MM to 73% for brexucabtagene autoleucel in MCL. Highest incidence of Grade ≥2 CRS was observed among MCL patients, whereas Grade ≥3 CRS was most commonly observed among FL patients. Time to onset of CRS ranged from 0 to 16 days, with median onset between 3-4 days among lymphoma patients and earlier median onset of 1 day for MM patients. Median time to CRS resolution ranged from 2 to 6 days across indications. While 81-95% of patients received CAR-T therapy at an academic center, 5-14% received CAR-T therapy at a community center. Tocilizumab and corticosteroids were the most commonly used treatments for CRS, including 37-48% use of tocilizumab for Grade 1 CRS (Table 2). Discussion: This study uniquely summarizes RWD on CRS following the use of commercially available CAR-T therapies across multiple hematologic malignancies, based on information from clinical notes abstracted retrospectively from EHRs. Consistent with the timing of approval of commercially available CAR-T therapies, the sample size for MM was limited compared with other malignancies. Safety events are typically under-reported in RWD sources, specifically for CRS when relying on information documented in patients' EHRs, compared with other published literature. In accordance with other RWD on CRS, grading criteria for CRS as well as vasopressor and oxygen use were not consistently reported in patients' EHRs. CAR-T treatments were predominantly administered in academic centers. Limited use in community practices was also observed; however, further information to accurately characterize the size and capabilities of community centers was not available in this database. Data also showed considerable use of tocilizumab to treat low-grade CRS, suggesting the need for additional evidence on its role to treat CRS beyond its current regulatory approval. Increased evidence generation, specifically from usual clinical practice, can contribute to increased awareness and knowledge about CRS diagnosis and management, and in turn realize the maximum potential of T-cell therapeutics.

Health Care Resource Utilization (HCRU) and Cost of Management of Cytokine Release Syndrome (CRS) and Neurological Events (NEs) in Patients with R/R CLL/SLL Receiving Lisocabtagene Maraleucel (liso-cel) Treatment in the TRANSCEND CLL 004 Study

Background:Liso-cel is an autologous, CD19-directed, 4-1BB CAR T cell product administered at equal target doses of CD8 + and CD4 + CAR + T cells, which is currently being evaluated for treatment of patients with R/R CLL/SLL in the TRANSCEND CLL 004 study (NCT03331198). Initial study results suggested that a single infusion induced CRs or remission in patients with R/R CLL/SLL and had a manageable safety profile, with low to moderate incidence of severe CRS and NEs (Siddiqi T, et al. Lancet 2023). While the clinical consequences of CRS/NEs associated with CAR T cell therapies are well understood, limited data are available on the cost of management of these AEs. This analysis evaluated HCRU and estimated costs of managing CRS/NEs by grade in patients with R/R CLL/SLL who received liso-cel treatment in TRANSCEND CLL 004. Methods: Case report forms were analyzed from the trial database, capturing patient-level HCRU related to the management of CRS/NEs. Only patients that received liso-cel at a dose level of 100 × 10 6 CAR + T cells (dose level 2 [DL2]) and subsequently experienced treatment-emergent CRS and/or NEs were included in this study. Treatment-emergent AEs were defined as those initiated within a 90-day period of liso-cel administration. Costs for management of CRS/NEs were estimated using microcosting methodology. Relevant HCRU observed from the day of AE onset through resolution that was associated with the management of CRS/NEs per protocol management guidelines was identified; unit costs sourced from public databases were applied to each HCRU. Included HCRU categories were: facility (standard inpatient admission, ICU stay), diagnostics (laboratory, imaging), medications (tocilizumab, corticosteroids, vasopressors), and procedures (dialysis, intubation). Cost analyses were conducted from the United States (US) health care system perspective and adjusted to 2023 US dollars. Unit costs were obtained from the US Centers for Medicare & Medicaid Services Hospital Outpatient Prospective Payment System, laboratory and physician fee schedules, IBM ® Micromedex ® RED BOOK ®, and literature. Descriptive statistical analyses stratified by AE severity grade and type of AE experienced were performed. Results: Ninety-four of 108 (87%) patients who received liso-cel at DL2 experienced CRS and/or NEs; 68 (72%) were grade ≤ 2 and 26 (28%) were grade ≥ 3. Overall, 44 (47%) patients had CRS only, 1 (1%) had NEs only, and 49 (52%) experienced both CRS and NEs. The study sample had a mean (standard deviation) age of 64.5 y (7.9) and were predominantly male (69%), White (84%), and non-Hispanic or Latino (90%). HCRU and total length of stay (LOS; the sum of inpatient and ICU stay days) are shown in the Table. All patients had an inpatient stay. ICU admissions only occurred among patients who experienced both CRS and NEs (10/49 [20%]) and were more common among patients with grade ≥ 3 (29%) compared with grade ≤ 2 (12%) AEs. Among patients who had an ICU admission, the median duration of an ICU stay was 5 days. Median total LOS increased with increasing AE severity for patients who had CRS only (grade 1, 5 days; grade 2, 9 days; grade 3, 15 days) and for patients who experienced both CRS and NEs (grade ≤ 2, 12 days; grade ≥ 3, 15 days). Overall, 68% and 62% of patients received tocilizumab and corticosteroids, respectively. Patients with grade ≥ 3 CRS and/or NEs had higher rates of utilization of medications, diagnostics, and procedures than those with grade ≤ 2 (Table). Additionally, patients who experienced both CRS and NEs had higher rates of utilization across all HCRU categories compared with those who experienced CRS or NEs only (Table). Estimated median management costs for CRS or NEs ranged from $14,638 (CRS only grade 1) to $46,802 (experienced both CRS and NEs with CRS or NEs grade ≥ 3) (Figure). Facility-related costs were the largest contributor to median total costs. Conclusions: While most patients treated with liso-cel at DL2 in TRANSCEND CLL 004 experienced CRS and/or NEs, they were primarily of low severity. HCRU and associated costs for management of CRS and/or NEs after liso-cel infusion increased with AE severity.Although everyone in this study required hospitalization, ICU admissions were rare and only observed among patients who experienced both CRS and NEs. Overall, costs of managing CRS and/or NEs were modest.

Implementation of Clinical Pathways for CAR-T Cell Therapy in a Brazilian Private Healthcare Organization

Introduction: the treatment with CAR-T cells in Brazil is challenging because it requires a highly qualified multidisciplinary team trained in new clinical pathways to take care of these patients. Objective: to describe the implementation of the clinical pathways for CAR-T cell therapy, ensuring safety and quality. Method: this is an experience report study, performed in four private general hospitals of the Americas from São Paulo, Rio de Janeiro and Ceará states, during the year of 2022. The process of implementing the CAR-T Cell clinical pathway included: creation of a medical committee with the main medical references and specialist nurses from each center, for the elaboration of the main clinical protocols and operational procedures, in addition to the discussion of eligibility cases for therapy with CAR-T Cells. Identification of the multidisciplinary reference team in all phases of treatment, training the team involved in the clinical care of the patient, and finally, establishment of patient clinical pathway before, during and after the CAR-T cell therapy. The implementation process lasted seven months between the qualification of centers by the Therapy provider, internal qualification each center and the first cell infusion with CAR-T Cell performed. Results: In all hospitals, professionals from the multidisciplinary team (pharmacy, nursing, physicians - hematologists, pediatric hematology-oncologists involved in hematopoietic stem cell transplantation, neurologists, pediatric and adult intensive care physicians) were trained. The Multidisciplinary Care Protocol was elaborated including indications, early and late complications. The Standard Operating Procedures addressed the pre and post infusion care, daily screening, criteria to transfer the patients to the intensive care unit, recognition and management of cytokine release syndrome and neurological toxicities. The main challenges of this process were to create the routines for evaluation and systematic monitoring and to identify and involve the multidisciplinary professionals directly involved in patient care. Conclusions: the implementation of the program brought improvements to the clinical pathway, positively impacting professional satisfaction, the quality and safety of the patients. The CAR-T cell therapy was performed in a safe and integrated environment, uneventful and successful.

Real-World Patient Profile and Step-up Dosing Process of Early Initiators of Teclistamab for Multiple Myeloma in US Hospitals - an Updated Analysis Using Premier Healthcare Database

Introduction: Teclistamab, a first-in-class B-cell maturation antigen (BCMA) x CD3 bispecific antibody with a personalized, weight-based dosing schedule, gained US regulatory approval in October 2022 for the treatment of triple-class exposed relapsed/refractory multiple myeloma (MM). Teclistamab administration is initiated with a step-up dosing (SUD) period, which includes two step-up doses followed by the first treatment dose. In a prior analysis of 40 patients, we found that early initiators of teclistamab were elderly, diverse, and had significant comorbidities, yet most of the patients completed SUD without delay (Tan SOHO 2023). To continue describing the real-world profile of patients initiating this novel therapy, we updated the prior analysis with a larger sample size and more data. This updated analysis revisited outcomes reported previously, including patient characteristics and SUD process, and evaluated the incidence and management of cytokine release syndrome (CRS) observed in the real-world United States (US) hospital setting. Methods: This was a real-world, retrospective, observational study using the Premier Healthcare Database, a hospital chargemaster database covering approximately 20% of US hospitals. We identified hospital encounters with ≥1 teclistamab administration between November 1, 2022 and April 1, 2023, with the earliest encounter as index. To be included, patients were required to have ≥1 diagnosis of MM (International Classification of Diseases, 10 th Revision, Clinical Modification [ICD-10-CM]: C90.0x) on or prior to index, ≥18 years of age on index, and no evidence of clinical trial engagement on or after index. We descriptively analyzed characteristics across all patients in the study, and SUD patterns and CRS in those who completed SUD. CRS was identified in two ways: ICD-10-CM codes and a published algorithm of CRS-related symptom and treatment codes (Keating algorithm). Results: A total of 113 patients with ≥1 teclistamab administration were included. Median (interquartile range) age was 65.0 (58-74) years; 21.2% were age ≥75 years; 61.1% had Medicare insurance. Most were male (61.1%), White (65.5%), and non-Hispanic (82.3%), with 21.2% Black. Most patients were treated at urban (97.4%) teaching hospitals (84.1%) with ≥300 beds (89.4%). During hospital encounter for SUD, 62.0% of patients had documented hypertension, 57.5% had anemia, 38.9% had renal impairment/failure, and 36.3% had peripheral neuropathy. Of 88 patients with available dose strength data, 58 (65.9%) completed SUD by data cut-off, with all SUD doses administered in one inpatient admission. Similar to the prior report, the mean (standard deviation) length of stay was 8.6 (1.7) days after omitting extreme outliers. Most patients had a 3-day (39.7%) or 2-day (20.7%) interval between SUD doses. Among the 58 patients who completed SUD, 25.9% of patients had an ICD-10-CM diagnosis code for CRS, with 19.0% with grade 1 and 6.9% with grade 2 as the highest grade. Per the Keating algorithm, 46.6% of patients experienced CRS-related symptoms, and a majority (41.4%) were classified as mild CRS. The most common symptoms indicative of CRS were fever (24.1%) and hypotension (17.2%) (Table 1). At any time during SUD, 10.3% patients received tocilizumab, 100% received corticosteroids, and 87.9% received acetaminophen (Table 2). Conclusion: This updated analysis of the first national real-world study of teclistamab confirmed that these initial patients were diverse, elderly, and had significant comorbidities, and most completed SUD without delay. Additionally, fewer than half of patients in this real-world cohort experienced CRS, as identified using ICD-10-CM codes. Limitations of our analysis include the small sample size, reliance on chargemaster data with inherent limitations (e.g., misclassification and coding errors), and the estimation of CRS incidence and management using diagnosis codes. However, this is the largest, real-world hospital-data analysis of patients initiating teclistamab within the first 5 months of market availability. Further updates are needed to augment the data with more patients and longer follow-up time.

Health Care Resource Utilization (HCRU) and Cost of Management of Cytokine Release Syndrome (CRS) and Neurological Events (NEs) in Patients with R/R Follicular Lymphoma (FL) Receiving Lisocabtagene Maraleucel (liso-cel) in the TRANSCEND FL Study

Background: Adverse events (AEs) such as CRS and NEs of varying severity have been associated with CAR T cell therapies, including liso-cel, an autologous, CD19-directed, 4-1BB CAR T cell product administered at equal target doses of CD8 + and CD4 + CAR + T cells. Liso-cel has previously demonstrated clinically meaningful responses in patients with R/R FL in the phase 2 TRANSCEND FL study (NCT04245839). In addition, previous research among patients with large B-cell lymphoma has suggested an acceptable safety profile with few grade ≥ 3 CRS/NEs, and safety data from TRANSCEND FL are in line with this larger dataset. However, there is limited to no research published on estimates of HCRU and costs related to the management of CRS/NEs among liso-cel-treated patients with FL. This analysis evaluated HCRU and estimated costs of managing CRS/NEs by grade and concurrency for patients with R/R FL who received liso-cel treatment in the TRANSCEND FL study. Methods: Retrospective analyses were conducted for liso-cel-treated patients with R/R FL (second line or later) who experienced CRS/NEs within 90 days after infusion using patient-level HCRU data from the TRANSCEND FL study databases. HCRU captured included facility (standard inpatient [IP] and ICU hospitalizations), length of stay (LOS), diagnostics (eg, laboratory and imaging), procedures (eg, dialysis and mechanical ventilation), and medications (eg, oncology supportive care, prophylactics, and other AE management). Costs of managing CRS/NEs were estimated using a microcosting methodology in which 1) HCRU from the time of AE onset through resolution was identified and 2) the most recently available unit costs sourced from public databases or literature (US Centers for Medicare and Medicaid Services, Healthcare Cost and Utilization Project, and IBM ® Micromedex ® RED BOOK ®) were applied to each HCRU and adjusted to 2023 US dollars using the Consumer Price Index. Analyses were stratified by AE grade and concurrency of events (CRS or NEs only, nonconcurrent CRS and NEs, and concurrent CRS and NEs). Patients with nonconcurrent and concurrent CRS/NEs were categorized by the highest-grade event experienced. Results: CRS only occurred in 59/130 (45%) patients, NEs only occurred in 4/130 (3%), and CRS and/or NEs occurred in 79/130 (61%). Of the 79 patients who experienced CRS and/or NEs, 75 (95%) were grade ≤ 2 and 4 (5%) were grade 3; no grade 4 or 5 CRS/NEs were observed. Most CRS/NEs were experienced as a single event (63/79 [80%]). Patients who experienced CRS and/or NEs had a median (range) age of 60 (23‒78) years and were predominantly male (51/79 [65%]). Estimated median management costs ranged from $20,306 (grade 1 CRS only) to $50,400 (grade 3 CRS or NEs; Figure). The largest contributor to median management costs across CRS/NE categories was facility HCRU. Key HCRU and total LOS (standard IP hospitalization and ICU stay days among hospitalized patients) are shown in the Table. Almost all patients (78/79 [99%]) had a standard IP hospitalization, and only 1 patient (1%) with a grade 3 CRS only event was admitted to the ICU. Median (range) total LOS for IP/ICU admission was 1.5 days longer among patients with grade 3 versus grade ≤ 2 CRS and/or NEs (5.5 [3‒8] days vs 4 [1‒14] days). Although there were very few grade 3 events (n = 4) to assess, patients with grade 3 versus grade ≤ 2 CRS and/or NEs also had higher rates of utilization for some medications (eg, tocilizumab: 3/4 [75%] vs 28/75 [37%]; corticosteroids: 4/4 [100%] vs 19/75 [25%]). Conclusions: While most patients with R/R FL treated with liso-cel in the TRANSCEND FL study experienced treatment-emergent CRS and/or NEs, they were almost all of low severity (grade ≤ 2) and experienced as single events. Management costs for CRS/NEs, primarily related to facility HCRU, increased with greater AE severity and concurrency. The additional median cost for a patient with grade 3 versus grade ≤ 2 CRS or NEs was $22,586, representing an 88% increase in cost; however, this finding must be considered in the context of the small number of overall grade 3 events (n = 4) and ICU admissions (n = 1). CAR T cell therapies with few associated higher severity AEs provide a potential option to optimize resource use and costs for the management of CRS/NEs in patients with FL.

Assessment of Early Intervention Strategies for Management of Cytokine Release Syndrome and Neurologic Events after Brexucabtagene Autoleucel (Brexu-Cel) Treatment in Patients with Relapsed or Refractory Mantle Cell Lymphoma (R/R MCL) in ZUMA-2

Introduction: Brexu-cel is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved in the United States for the treatment of adults with R/R MCL and in the European Union for adults with R/R MCL after ≥2 prior therapies, including a Bruton tyrosine kinase inhibitor (BTKi). In the Phase 2 ZUMA-2 study, with a median follow-up of 35.6 months, brexu-cel showed an objective response rate of 91%, a median duration of response of 28.2 months, and a median overall survival of 46.6 months with a manageable safety profile in treated patients (pts) with R/R MCL (N=68). Grade (Gr) ≥3 infections, cytokine release syndrome (CRS), and neurologic events (NEs) occurred in 37%, 15%, and 31% of pts, respectively (Wang et al. J Clin Oncol. 2023). In August 2018, CRS and NE management strategies for ZUMA-2 were updated to initiate treatment of these adverse events earlier at the onset of Gr 1 events to improve safety outcomes. Here, we report 4-yr safety outcomes for pts in ZUMA-2 by initial and updated CRS and NE management strategies. Methods: Pts with R/R MCL and ≤5 prior treatments, including a BTKi, underwent leukapheresis and conditioning chemotherapy followed by a single infusion of brexu-cel (2×10 6 CAR T cells/kg). For CRS, the initial toxicity management strategy was to consider tocilizumab ± corticosteroids (methylprednisolone 1 mg/kg bid or dexamethasone 10 mg q6h) for Gr 2 CRS with extensive comorbidities or older age and Gr 3 CRS, and to increase the dose of corticosteroids (methylprednisolone 1 g/day x3, followed by a rapid taper consisting of 250 mg bid x2 days, 125 mg bid x2 days and then 60 mg bid x2 days) for Gr 4 CRS. The updated guidance was to administer tocilizumab for Gr 1/2 CRS that does not improve after 24 hours, and tocilizumab + corticosteroids (only if no resolution after 24 hours) and vasopressors for Gr 2 and 3 CRS. For NEs, the initial guidance was to consider use of tocilizumab for Gr 2 NEs only if other comorbid conditions exist (8 mg/kg IV over 1 hour, not to exceed 800 mg) and to add corticosteroids (dexamethasone 10 mg IV q6h, methylprednisolone 1 mg/kg bid) for Gr ≥3 NEs. In the updated guidance, steroid treatment without concurrent CRS remained the same, but both tocilizumab + dexamethasone 10 mg IV were to be administered for Gr ≥2 NEs concurrent with CRS. Both guidance protocols recommended treatment with antibiotics for management of infections. This exploratory post hoc analysis examined safety outcomes related to CRS, NEs, and infections for pts in each management group, with descriptive statistics reported. Results: As of July 23 2022, the median follow-up in the 68 treated pts was 47.5 months (range, 37.9-68.3). Of these pts, 40 received updated guidance (early intervention group [EIG]) and 28 received initial guidance (later intervention group [LIG]). Gr ≥3 CRS events were experienced at similar rates in both groups while Gr ≥3 NEs and Gr ≥3 infections occurred less often in the EIG vs the LIG (Table). Gr 5 infections occurred in 2 pts in the EIG and 0 pts in the LIG. No Gr 5 CRS or NEs occurred in either group. The median durations of Gr ≥3 CRS and infections were shorter for the EIG than the LIG while the median duration of Gr ≥3 NEs was longer for the EIG. Any Gr CRS and NEs were resolved at similar rates in both groups, but fewer any Gr infections were resolved for the EIG (all unresolved events in both groups were due to pt death before event resolution). Concomitant medications of interest were used in 80% (n=32) and 82% (n=23) of pts in the EIG and LIG, respectively. Tocilizumab was used at similar rates in the EIG and LIG (73% vs 68%), but steroids (55% vs 68%), vasopressors (18% vs 29%), and immunoglobulins (28% vs 50%) were used at lower rates in the EIG. Median CAR T-cell peak levels and area under the curve were lower for the EIG than the LIG while median CAR T-cell levels peaked at similar times in both groups. Conclusions: With an updated safety management protocol emphasizing early intervention with tocilizumab and corticosteroids for CRS and NEs, only 20% of pts had Gr ≥3 NEs and 30% had Gr ≥3 infections. Additionally, a lower percentage of EIG pts required steroid, vasopressor, and immunoglobulin use than pts in the LIG. CAR T-cell expansion levels were numerically lower in the EIG. Although limited by small pt numbers, these findings support the current clinical guidance for safety management during brexu-cel treatment, which is close to the ZUMA-2 updated toxicity management guidance that was examined in this study.

Cytokine Release Syndrome: The Patient, Caregiver and Healthcare Professional Experience

Background: Cytokine release syndrome (CRS) is a supraphysiologic response to T-cell engaging immunotherapy that can negatively impact the treatment experience of patients with non-Hodgkin lymphoma (NHL) and other blood cancers. We explored patient, caregiver and healthcare professional (HCP) perspectives on key burdens and unmet needs associated with CRS. Methods: Existing insights from disease-level patient journeys (follicular lymphoma, diffuse large B-cell lymphoma, multiple myeloma [MM]) and reports from focus groups with a CRS patient working group from the USA, UK, Canada, and Belgium were assessed to identify key questions. Further interviews were conducted (November 2022-January 2023) in the USA, UK, Germany, and Austria to address these questions with patients, caregivers and HCPs. HCP insights were collected via 60-minute virtual interviews; patient and caregiver insights were collected via video homework tasks and 60-minute virtual interviews. Outputs were validated by the working group, consisting of patients with CRS experience and representatives of patient organizations. Results: A total of 34 HCPs (hemato-oncologists, n=24; nurses, n=10; Tables 1 & 2) with varying degrees of experience of managing CRS were interviewed, along with 9 patients and 3 caregivers (associated diagnoses: NHL, n=6; MM, n=5; acute lymphocytic leukemia, n=1). All patients had experienced CRS (Grade 1-3) as a result of CAR T-cell (n=6) or bispecific antibody (n=3) therapy. Insights were based on five focus areas: 1) patient education and information; 2) CRS diagnosis and management; 3) CRS in different healthcare archetypes; 4) digital literacy and the role of technology in mitigating/monitoring/managing CRS; and 5) the caregiver perspective. CRS education was a primary unmet need, but overall awareness and knowledge of CRS was strong among the patient sample. Patients noted the life-threatening potential of CRS, but preferred to be on active treatment. HCP communication to patients focused on CRS being an expected occurrence rather than a marker of treatment failure, the need for in-patient admission in some cases and/or close monitoring, and the critical role of caregivers. Generally, HCPs were familiar with CRS and the procedures for its monitoring and management, but the variability in time to onset, severity of symptoms, and potential impact on quality of life (QOL) warranted caution. Logistics emerged as a common barrier, with CRS treatment often administered at major hospitals, as local, community-based clinics do not currently have the required capacity/capability to manage CRS; this could be achieved via the provision of training and support. Uncertainty remains regarding the broader roll out of bispecific antibodies, given the variability in CRS treatment between countries. Patients, HCPs and caregivers were aligned on their preferences for remote monitoring for CRS. All three groups expressed the need for simple, easy-to-use solutions that integrate seamlessly with existing systems and do not cause undue concern with false alarms, complex technical set-up and patient user experience. Patients emphasized the need for prompt and assured access to their medical team in case of an emergency. HCPs expressed a range of opinions on the feasibility of adopting such solutions. Some were open to using new tools and saw the potential for alleviating resource challenges. Others had reservations about interoperability and questions around over-informing patients with detailed data. Patients were open to adopting new technologies, if they added tangible benefit to their QOL, avoided additional logistical burden and improved their experience. Conclusions: There is strong awareness among patients, caregivers, and HCPs of the risks associated with CRS and the potential impact on QOL. HCPs with experience in administering cellular immunotherapies are confident in monitoring and managing CRS; however, its unpredictability and logistical burden need to be addressed. There is value in adopting digital solutions for CRS monitoring and management. Concerns remain around interoperability, data stewardship, and integration and validation within current hospital systems. Patients' concerns regarding the useability of such digital solutions and assured data privacy also need to be addressed as part of solution development in the CRS space.

Glofitamab Plus Polatuzumab Vedotin Continues to Demonstrate Frequent and Durable Responses and Has a Manageable Safety Profile in Patients with ≥2L Relapsed/Refractory DLBCL, Including HGBCL, and in Patients with Prior CAR T-Cell Therapy: Updated Results from a Phase Ib/II Study

Background: Glofitamab (Glofit) is a CD20xCD3 bispecific antibody which engages and redirects T cells to eliminate B cells. Glofit monotherapy recently received FDA and EMA approval for treatment of relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) after ≥2 prior lines of therapy. Polatuzumab vedotin (Pola) is a CD79b-targeted antibody-drug conjugate that has a complementary mode of action to Glofit, with little toxicity overlap. In this open-label, multicenter Phase Ib/II study (NCT03533283), Glofit+Pola demonstrated durable responses and a manageable safety profile in patients with R/R DLBCL (Hutchings et al. ICML 2023). We present updated results with longer follow-up in patients with R/R DLBCL, including high-grade B-cell lymphoma (HGBCL), and in patients with prior chimeric antigen receptor (CAR) T-cell therapy. Methods: Patients receivedobinutuzumab 1000mg on Cycle (C) 1 Day (D) 1 to mitigate the risk of severe cytokine release syndrome (CRS). Pola 1.8mg/kg was given on C1D2 and D1 of C2-6 (21-day cycles). Glofit was given with step-up dosing in C1 (C1D8 2.5mg; C1D15 10mg; D1 of C2-12 10/30mg) for up to 12 cycles. The primary objective was to establish the recommended Phase II dose of Glofit when combined with Pola; this was previously identified as 30mg based on the dose-escalation phase and the NCT03075696 study (Hutchings et al. ASH 2021; Hutchings et al. J Clin Oncol 2021). Results: At the data cut-off (Jan 25, 2023), 111 patients had received ≥1 dose of study drug (safety population). The median age was 68 (range 23-82) years; 61.3% of patients were male; 50.5% had DLBCL not otherwise specified (NOS), 24.3% had HGBCL, 23.4% had transformed follicular lymphoma (trFL), and 1.8% had primary mediastinal large B-cell lymphoma (PMBCL). Most patients were refractory to their last prior therapy (71.2%). Median number of prior lines of therapy was 2 (range 1-7; 61.3% of patients had received ≥2), 24.3% had received prior CAR T-cell therapy. The overall response rate (ORR) in 109 efficacy-evaluable patients was 78.0%, with a complete metabolic response (CMR) rate of 56.0%. In patients with DLBCL NOS (n=56), ORR and CMR rate were 85.7% and 60.7%, respectively. In patients with trFL (n=26), ORR and CMR rate were 76.9% and 53.8%, respectively. In patients with HGBCL (n=25), ORR and CMR rate were 60.0% and 44.0%, respectively. The two patients with PMBCL achieved a CMR. In patients who had prior CAR T-cell therapy (n=27), ORR was 77.8% and CMR rate was 44.4%. In 61 patients who had a complete response, estimated 6- and 12-month duration of complete response (DOCR) rates were 89.2% and 73.1%, respectively ( Figure). Estimated 6-month and 12-month DOCR rates in patients with DLBCL NOS (n=34) were 84.2% and 59.2%, respectively; with trFL (n=14), were 92.9% and 85.7%; with HGBCL (n=11), both were 100%. In patients with PMBCL (n=2), the estimated 6-month DOCR was 100%. With a median follow-up of 13.0 months, median progression-free survival was 10.4 (95% confidence interval [CI]: 5.8-19.0) months ( Figure). Median overall survival was not reached after a median survival follow-up of 15.2 months. In 108/111 patients who had received ≥1 dose of Glofit, the most common adverse event (AE) was CRS (45.4% [Grade 1, 30.5%; Grade 2, 13.9%]). One patient had Grade 5 CRS in the context of an unresolved infection; the patient declined further CRS management when the event was Grade 3. Of 111 safety-evaluable patients, 27 (24.3%) had peripheral neuropathy (all Grade 1/2, 8 events were resolved). Glofit-related AEs potentially consistent with immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 3 patients and were all Grade 1/2. Grade 3/4 AEs were reported in 61.3% of patients, with neutropenia the most common event (29.7%). Serious AEs occurred in 58.6% of patients, and Grade 5 AEs occurred in 6.3% of patients (5/7 events due to COVID-19); 9.9% of patients discontinued any treatment due to an AE (6.3% discontinued Pola; 9.0% discontinued Glofit). Conclusions: Glofit+Pola demonstrated high response rates and durable responses in heavily pre-treated patients, the majority of whom were refractory to their last prior therapy, across all histologies, including in patients with HGBCL and those with prior CAR T-cell therapy. The safety profile was manageable and consistent with the individual drugs. The rates of CRS events and AEs potentially consistent with ICANS were low. Updated data will be presented.

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).

A Phase II Trial of Prophylactic Anakinra to Prevent Neurotoxicity in Patients Receiving Anti-CD19 CAR T-Cell Therapy for Relapsed or Refractory Lymphoma: Final Results from Cohort 2

Background: Whilst tocilizumab is effective in the management of chimeric antigen receptor T-cell (CAR-T) associated cytokine release syndrome (CRS), there are no targeted therapies for immune effector cell-associated neurotoxicity syndrome (ICANS). Rates of severe (≥ grade 3) ICANS remain high with axicabtagene (axi-cel) and brexucabtagene (brexu-cel) at > 30%. Preclinical models have shown that anakinra, an IL-1 receptor antagonist, reduced CAR-mediated immune toxicities without affecting efficacy. Based on these data, we conducted a phase 2 trial of prophylactic anakinra in patients receiving commercial anti-CD19 CAR-T for r/r B-cell lymphoma (NCT04148430). The study had sequential enrollment in 2 independent cohorts. We recently reported results from cohort 1 in which patients received subcutaneous (SC) anakinra from day 2 until at least day 10 post-CAR infusion and showed that prophylactic anakinra reduced the rate of severe ICANS to 9.7% (Park, Nat Med, 2023). Herein, we report results from cohort 2 of the study where we utilized anakinra as a complete prophylactic strategy. Methods: Adult patients with a diagnosis of r/r large B-cell lymphoma (LBCL), high-grade B-cell lymphoma (HGBCL), follicular lymphoma (FL) or mantle cell lymphoma (MCL) receiving commercial anti-CD19 CAR-T were enrolled. Patients received SC anakinra 100 mg daily from day 0 for at least 7 d. The frequency of anakinra could be increased up to 100 mg every 6 h, and the duration beyond 7 d for persistent or progressive CRS and ICANS. Tocilizumab and steroid use were allowed for the management of persistent or progressive CRS and ICANS. A baseline and day 5 lumbar puncture were performed for CSF analysis. The primary endpoint was the rate of severe ICANS, graded per the ASTCT criteria. Secondary endpoints included rates of severe CRS, all grade CRS and ICANS, overall response rate (ORR), survival outcomes, and serum and CSF biomarker levels. Results: 37 patients were screened, 31 enrolled, and 30 treated (LBCL=13, HGBCL=6, FL=6, MCL=5). 1 enrolled patient did not proceed with treatment due to COVID-19 infection. The median age of the cohort was 65yrs (range: 24 - 81yrs) and patients received axi-cel (19 pts; 63%), brexu-cel (5 pts; 17%), lisocabtagene (4 pts; 13%) and tisagenlecleucel (2 pts; 7%). Patients received a median 3 prior lines of therapy (range: 1 - 7); 22 (73%) were refractory to their immediate prior therapy; 17 (57%) received bridging therapy and 3 (10%) had active CNS disease at CAR infusion. Pretherapy tumor burden as measured by the median sum of the products of diameters was 1638mm 2 (range: 0 - 21,570mm 2). All patients started anakinra on day 0. Anakinra administration was increased in 24 patients (80%) during CRS; it was increased to a maximum of 100mg q12h in 1 patient and 100mg q6h in 23 patients. The median duration of anakinra administration was 9.5 d (IQR 8 - 13). No patient stopped anakinra due to an adverse event. A total of 3 patients (10%) experienced severe ICANS, all of which were grade 3 only. 9 patients (30%) experienced any grade ICANS (Fig 1A). The median time to ICANS onset was 6.5 d (range: 4 - 10 d). All-grade CRS occurred in 24 patients (80%). Most CRS events were grade 1 or 2 except for 3 grade 3 events (10%) (Fig 1A). Of the 24 patients who received CD28-containing CARs (axi-cel and brexu-cel), all-grade and severe ICANS rate was 29% and 12.5%, respectively (Fig 1B). In the 3 patients with active CNS disease, there was 1 grade 2, and 1 grade 3 ICANS event. 23 patients (77%) received tocilizumab and 18 (60%) received steroids for CRS and/or ICANS. The median follow-up was 5.8mo. The best ORR by day 100 was 83% (95% CI 65-94%) with a CR rate of 73% (95% CI 54-89%). The estimated progression-free and overall survival at 6mo was 72% (95% CI 50-93%) and 81% (95% CI 66-86%), respectively. Conclusion: Early use of prophylactic anakinra was safe, feasible and reduced the rate of severe ICANS without affecting efficacy in adult patients receiving anti-CD19 CAR-T for r/r B-cell lymphoma. Rates of severe ICANS were very similar between cohorts 1 and 2; at 9.7% and 10% in the entire cohorts, respectively, and 11% and 12.5% in patients treated with CD28-containing CARs, respectively. The risk-adapted dosing of anakinra likely contributed to the low rates of severe ICANS in this study. Detailed comparison of results from cohort 1, analysis of the anakinra dose-relationship on efficacy, and serum and CSF biomarkers will be presented at the meeting.

Efficacy of Siltuximab for Chimeric Antigen Receptor T-Cell Therapy Toxicities - a Multicenter Retrospective Analysis

Background: Chimeric Antigen Receptor T-Cell therapies (CAR-T) are effective in a variety of hematologic (hem) malignancies; however, adverse events including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) can affect a significant number of patients (pts). Tocilizumab, a monoclonal antibody (mAb) binding the interleukin-6 (IL-6) receptor, is the standard of care for managing CRS, but is ineffective for ICANS. Corticosteroids remain the standard of care for managing ICANS. Pts who develop refractory CRS or ICANS have few treatment options. Siltuximab, a mAb binding circulating IL-6, has been proposed to have clinical activity in both CRS and ICANS (Patel, ASH, 2022; Narkhede, TCT, 2023). This study assesses the efficacy of siltuximab for managing CRS and ICANS in a real-world cohort from six academic medical centers. Methods: We conducted a multicenter retrospective review of adult pts with hem malignancies treated with CAR-T therapy who received siltuximab for treatment of CRS and/or ICANS. Siltuximab administration occurred between January 2020 and August 2022. Pts who died within 48 hours of siltuximab administration (n=2) were excluded from this analysis. The co-primary endpoints were the percentage of pts who had improvement in CRS or ICANS after receiving siltuximab. Secondary endpoints included time to improvement of CRS or ICANS and overall survival (OS) from the date of CAR-T infusion. Time to event endpoints were evaluated by Kaplan-Meier methodology. Results: Fifty-two pts were eligible and evaluated. The median age was 60 years (range 23-81). Diffuse large B-cell lymphoma was the most common hem malignancy (52%). Axicabtagene ciloleucel (42%) was the most common cellular therapy product. Table 1 describes disease subtypes and cell therapy products in detail. Fifty-one pts (98%) developed CRS with median time to onset of 2 days (range 0-9). Max CRS grade prior to siltuximab administration was grade 1-2 in 83% and grade 3-4 in 15%. ICANS occurred in 65% with median time to onset of 6 days (range 0-16). Max ICANS grade prior to siltuximab administration was grade 1-2 in 29% and grade 3-4 in 37%. Prior to siltuximab, 52% of pts received tocilizumab with the majority (59%) receiving more than 1 dose, 69% of pts received corticosteroids, and 10 pts received additional treatments: anakinra (7/10 pts), LP with intrathecal (IT) chemo (3/10 pts), LP with IT steroids (2/10 pts), ruxolitinib (1/10 pt). Reasons for siltuximab administration included steroid refractory ICANS in 17 pts (33%), tocilizumab refractory CRS in 8 pts (15%), tocilizumab shortage in 26 pts (50%), and non-steroid refractory grade 4 ICANS in 1 pt (2%). At the time of siltuximab administration, 42 pts (81%) had evidence of CRS (10% grade 3-4 CRS) and 28 pts (54%) had evidence of ICANS (31% grade 3-4 ICANS). 18 pts (35%) had concurrent CRS and ICANS. Thirty-six pts (86%) had improved CRS grade following siltuximab treatment. The median time to CRS resolution after siltuximab was 1.5 days (range 0-18). Twelve pts with CRS received more than 1 dose of siltuximab. 4/8 pts (50%) with tocilizumab refractory CRS had improved CRS grade after siltuximab. Nineteen pts (68%) had improved ICANS grade following siltuximab treatment. The median time to ICANS resolution after siltuximab was 5 days (range 1-40). Nine pts with ICANS received more than 1 dose of siltuximab. 13/17 pts (76%) with steroid refractory ICANS had improved ICANS grade after siltuximab. The median time to discharge after siltuximab administration was 14 days (range 7-90). CAR-T therapy objective response rate was 73% and complete response rate was 48%. Twenty-one pts had died at the time of data collection; 4 deaths were deemed secondary to CAR-T toxicity. The median OS was 13.8 months (95% CI 9.6-NR) and was not statistically different based on indication of CAR-T therapy, Figure 1. Conclusions: To our knowledge, this is the largest cohort of pts treated with siltuximab for CRS and/or ICANS following CAR-T therapy. Half of the pts had CRS or ICANS refractory to tocilizumab and/or steroids. Siltuximab appeared to be effective for both CRS and ICANS, including refractory toxicities. These data support the use of siltuximab for refractory CRS and ICANS and warrant further investigation of siltuximab in earlier lines of therapy for CRS and ICANS management.

An Economic Model to Estimate Costs of Cytokine Release Syndrome and Neurological Events Among Patients Treated with CAR T Cell Therapies for Relapsed or Refractory Follicular Lymphoma

Background: CAR T cell therapies have exhibited promising clinical responses in populations that are traditionally challenging to treat. Axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) are 2 CAR T cell therapies now available in the United States (US) for the treatment of R/R follicular lymphoma (FL) after 2 or more lines of systemic therapy. Lisocabtagene maraleucel (liso-cel) is currently being investigated in clinical trials for the treatment of patients with R/R second-line high-risk and third line or later FL. As observed in other approved indications, the improved response and survival rates from the introduction of CAR T cell therapies are typically accompanied by the potential for AEs, such as cytokine release syndrome (CRS) and neurological events (NEs). However, the rates and severity of these AEs tend to vary across CAR T cell therapies. Understanding the economic implications of these 3 CAR T cell therapies and their associated AEs is crucial for informed decision-making and to underscore key economic and safety differences across the 3 CAR T cell therapies. The primary objective of this analysis was to estimate the average per-patient weighted costs of CRS and NEs for a patient with R/R FL treated with a CAR T cell therapy (liso-cel, axi-cel, or tisa-cel) based on clinical trial rates. Secondary objectives included estimates for (1) the opportunity cost of treating with axi-cel or tisa-cel versus liso-cel and (2) the additional number of patients eligible for treatment with liso-cel based on a hypothetical sample of 100 treated patients. Methods: An economic model was developed using data from the TRANSCEND FL (NCT04245839; n = 130), ZUMA-5 (NCT03105336; n = 124), and ELARA (NCT03568461; n = 97) studies. CRS and NE rates reported in the FL studies were incorporated in a decision analytic economic model to estimate costs from a health care system perspective in 2023 US dollars. Microcosting analysis data from the TRANSCEND FL study were used as CRS and NE cost inputs; the model assumed that CRS and NE management costs across CAR T cell therapies would not differ. The analysis used a Monte Carlo simulation approach to address uncertainty surrounding the clinical and economic data. The model output was a weighted average that represented cost for the average treated patient, including those with and without CRS and/or NEs. The average per-patient total cost difference between CAR T cell therapies was used to estimate the number of additional patients who could be treated with liso-cel versus axi-cel or tisa-cel. Results: Rates of CRS grade 1‒2/≥ 3 were 56.9/0.8% for liso-cel, 71.8%/6.5% for axi-cel, and 48.5%/0.0% for tisa-cel. Rates of NE grade 1‒2/≥ 3 were 13.1%/2.3% for liso-cel, 41.1%/ 15.3% for axi-cel, and 34.0%/ 3.1% for tisa-cel. The overall per-patient weighted average costs for CRS and NEs were estimated to be $20,626 for liso-cel, $44,096 for axi-cel, and $26,460 for tisa-cel (Figure). The per-patient weighted average cost per CRS event was $14,631 for liso-cel, $21,299 for axi-cel, and $12,456 for tisa-cel. The per-patient weighted average cost per NE was $5994, $22,797, and $14,004 for liso-cel, axi-cel, and tisa-cel, respectively. Total per-patient cost differences for liso-cel compared with axi-cel and tisa-cel were −$23,470 and −$5835, respectively. The resulting opportunity costs from treating 100 patients with liso-cel instead of axi-cel and tisa-cel would allow for the treatment of an additional 5.2 and 1.3 patients, respectively. Conclusions: This economic analysis revealed lower overall per-patient weighted average costs associated with liso-cel compared with axi-cel and tisa-cel, primarily due to lower CRS and NE rates versus axi-cel and lower NE rates versus tisa-cel. In comparison with axi-cel and tisa-cel, liso-cel demonstrated robust economic and clinical value, with lower rates of CRS and/or NEs associated with substantial cost savings per AE event.