Cytokine Release Syndrome Grade Research Articles

Abstract 4114505: Cardiovascular Adverse Events After Anti-BCMA CAR-T (Ide-Cel and Cilta-Cel) for Relapsed/ Refractory Multiple Myeloma

Introduction: Idecabtagene vicleucel (Ide-Cel) and ciltacabtagene autoleucel (Cilta-cel) are novel CAR-T therapies targeting B-cell maturation antigen (BCMA) and approved for relapsed and refractory multiple myeloma (RRMM). While cardiovascular adverse events (CVAE) are relatively common with CD-19 CAR-T, the incidence of CVAE in the real-world setting for anti-BCMA CAR-T in RRMM is largely unknown. This study aims to determine the incidence of CVAE and its associated risk factors in patients treated with ide-cel and cilta-cel. Method: This single-center retrospective cohort study evaluated RRMM patients treated with ide-cel and cilta-cel from May 2021 to December 2023. We assessed baseline cardiac and oncologic characteristics and clinical outcomes post-CAR-T. Cytokine release syndrome (CRS) and immune cell-associated neurologic syndrome (ICANS) grading followed ASTCT consensus guidelines. Result: A total of 164 RRMM patients treated with ide-cel (N=109) or cilta-cel (N=55) with at least 6 months follow-up were included. The average age was 63 years, and 57% were male. Advanced RRMM stage (R-ISS III) was present in 17% with a median of 6 prior lines of therapy. CRS grade equal or greater than 2 occurred in 22%, and ICANS grade equal or greater than 3 in 6.7%. Twenty patients (12.2%) experienced CVAE, including atrial fibrillation (7.9%), non-sustained ventricular arrhythmia (3.0%), heart failure (3.7%), and cardiovascular death (0.6%). R-ISS III was associated with increased CVAE (52.9% vs. 11.5%; P=0.001). Patients with CVAE had higher baseline ferritin and CRP levels and a higher incidence of CRS grade ≥ 2 (60% vs. 16.7%; P<0.001) and ICANS grade ≥ 3 (20% vs 4.9%; P=0.001). Treatment with tocilizumab, steroids, or anakinra was more common in patients with CVAE. Conclusion: CVAE occurred relatively frequently following BCMA CAR-T therapy, with high-grade CRS identified as a consistent risk factor. Most CVAEs were manageable with appropriate supportive care, including careful observation and active treatment of CRS.

INNV-30. TOXICITIES AND OUTCOME AFTER CD19-DIRECTED CHIMERIC ANTIGEN RECEPTOR T-CELL THERAPY FOR NEUROLYMPHOMATOSIS

Abstract BACKGROUND Lymphomatous infiltration of the peripheral nervous system (PNS), termed neurolymphomatosis, represents a distinct extranodal non-Hodgkin lymphoma variant with dismal outcome. CD19-directed chimeric antigen receptor (CD19-CAR) T-cell therapy has emerged as a safe and effective treatment for B-cell lymphomas. We aimed to assess toxicity and efficacy of CD19-CAR T-cells in neurolymphomatosis. METHODS Neurolymphomatosis treated with CD19-CAR T-cells were retrospectively identified at Massachusetts General Hospital over a six-year period. Toxicities were graded according to the ASTCT classification. Management, and response rates were recorded. RESULTS Eleven neurolymphomatosis cases, who had received a median 2 prior PNS-directed treatments (range: 1-3) before CD19-CAR T-cell exposure, were identified. Neurolymphomatosis localized to the nerve roots (8/11, 73%), plexus (5/11, 45%), peripheral (4/11, 36%) and cranial nerves (5/11, 45%). Low grade cytokine release syndrome was detected in 8/11 (73%; grade 1: N = 7; grade 2: N =1) cases. Low- and high-grade immune cell-associated neurotoxicity syndrome were recorded in 5/11 (45%; grade 1: N = 4; grade 2: N = 1) and 1/11 (9%; grade 4) patients, respectively. Seven of eleven neurolymphomatosis patients (64%) responded to CD19-CAR T-cells. Complete remissions were achieved in three cases (27%), of which two are still sustained now 9 and 46 months after CD19-CAR T-cell infusion. All radiographic responses were associated with remission of neurological symptoms. CONCLUSIONS CD19-CAR T-cell treatment was well tolerated and yielded promising efficacy in recurrent neurolymphomatosis, a difficult to treat condition with unmet medical need. Findings suggest that CD19-CAR may sufficiently penetrate the blood-nerve barrier, and toxicity and outcomes were overall similar to CAR-T cell therapy in CNS lymphoma.

Fluctuation of physical function during chimeric antigen receptor T‐cell therapy during rehabilitation intervention: Real‐world data and risk factor analyses

AbstractIntroductionPatients undergoing chimeric antigen receptor (CAR) T‐cell therapy face prolonged treatment timelines and are prone to cytokine release syndrome (CRS) and immune effector cell‐associated neurotoxicity syndrome (ICANS) after infusion. Disabilities in physical function and the importance of rehabilitation during CAR‐T‐cell therapy to maintain physical function have been poorly documented.MethodWe performed a retrospective cohort study to assess changes in exercise tolerance via differences in a 6‐min‐walking distance (Δ6MWD) and factors influencing it.ResultsA total of 77 patients who underwent rehabilitation during CAR‐T‐cell therapy were enrolled, and their 6MWD was 450 m (median, range 180–705 m) before and 450.5 m (107.0–735.0 m) 30 days after CAR‐T treatment. No significant alteration in Δ6MWD was observed overall (11.0 m, 95% confidence interval, −56.1 to 88.2 m). Multiple regression analyses indicated that age (over vs. under 65 years) revealed no notable differences in Δ6MWD (20 vs. 10 m), while ΔHb (β = 0.24, p = 0.03), moderate/severe CRS (grade 1 with continuous fever or grade ≥2; β = −0.25, p = 0.03), and ICANS (any grade; β = −0.22, p = 0.04) were significantly associated with lower Δ6MWD.ConclusionThis real‐world study indicated that CAR‐T‐cell therapy is less likely to reduce physical function even in older patients if rehabilitation is properly performed, whereas CRS and ICANS can be risk factors to deprive exercise tolerance.

Siltuximab for chimeric antigen receptor T-cell therapy–related CRS and ICANS: a multicenter retrospective analysis

AbstractChimeric antigen receptor T-cell (CAR-T) therapies are effective in many hematologic malignancies; however, adverse events including cytokine release syndrome (CRS) and immune effector cell–associated neurotoxicity syndrome (ICANS) can affect a significant number of patients. Those who develop refractory CRS or ICANS have few treatment options. Siltuximab, a monoclonal antibody binding circulating interleukin-6, has been proposed to have clinical activity in both CRS and ICANS. We conducted a multicenter retrospective analysis of siltuximab treatment for CRS and ICANS after CAR-T therapy in a real-world cohort from 6 academic centers. Fifty-four patients were evaluated. Sixteen patients had CRS previously treated with tocilizumab and 17 patients had ICANS previously treated with steroids. Of the patients with CRS at the time of siltuximab, 75% had improvement in CRS grade. Of the patients with ICANS at the time of siltuximab, 60% had improvement in ICANS grade. To our knowledge, this is the largest cohort of patients treated with siltuximab for CRS and/or ICANS after CAR-T therapies. Siltuximab appeared to be effective for both CRS and ICANS, including previously treated toxicities. These data support the use of siltuximab in CRS and ICANS as well as provide rationale for future prospective studies.

Anti-CD19 CAR-T cells are effective in severe idiopathic Lambert-Eaton myasthenic syndrome.

Lambert-Eaton myasthenic syndrome (LEMS) is an autoantibody-mediated disease of the neuromuscular junction characterized by muscular weakness. Autoantibodies to presynaptic P/Q-type voltage-gated calcium channels (VGCCs) induce defective neuromuscular function. In severe cases, current immunosuppressive and immunomodulatory treatment strategies are often insufficient. First reports show beneficial effects of anti-CD19 chimeric antigen receptor (CAR)-T cell therapy in patients with autoantibody-mediated myasthenia gravis. We report a patient with isolated idiopathic LEMS treated with autologous anti-CD19-CAR-T cells. In this patient, CAR-T infusion leads to expansion of predominantly CD4+ CAR-T cells with a terminally differentiated effector memory cells re-expressing CD45RA (TEMRA)-like phenotype indicating cytotoxic capabilities and subsequent B cell depletion. VGCC antibody titers decrease, resulting in a clinical improvement of LEMS symptoms, e.g., 8-fold increase in walking distance. The patient does not show relevant side effects except for cytokine release syndrome grade 2 and intermittent neutropenia suggesting that anti-CD19 CAR-T cell therapy may be a treatment option in patients with LEMS.

Fratricide-resistant CD7-CAR T cells in T-ALL.

T cell acute lymphoblastic leukemia (T-ALL) is difficult to treat when it relapses after therapy or is chemoresistant; the prognosis of patients with relapsed or refractory T-ALL is generally poor. We report a case series of 17 such patients who received autologous chimeric antigen receptor (CAR) T cells expressing an anti-CD7 CAR and an anti-CD7 protein expression blocker (PEBL), which prevented CAR T cell fratricide. Despite high leukemic burden and low CAR T cell dosing, 16 of the 17 patients attained minimal residual disease-negative complete remission within 1 month. The remaining patient had CD7- T-ALL cells before infusion, which persisted after infusion. Toxicities were mild: cytokine release syndrome grade 1 in ten patients and grade 2 in three patients; immune effector cell-associated neurotoxicity syndrome grade 1 in two patients. Eleven patients remained relapse-free (median follow-up, 15 months), including all nine patients who received an allotransplant. The first patient is in remission 55 months after infusion without further chemotherapy or transplantation; circulating CAR T cells were detectable for 2 years. T cells regenerating after lymphodepletion lacked CD7 expression, were polyclonal and responded to SARS-CoV-2 vaccination; CD7+ immune cells reemerged concomitantly with CAR T cell disappearance. In conclusion, autologous anti-CD7 PEBL-CAR T cells have powerful antileukemic activity and are potentially an effective option for the treatment of T-ALL.

The Kinetics of Inflammation-Related Proteins and Cytokines in Children Undergoing CAR-T Cell Therapy-Are They Biomarkers of Therapy-Related Toxicities?

CD19-targeted CAR-T cell therapy has revolutionized the treatment of relapsed/refractory (r/r) pre-B acute lymphoblastic leukemia (ALL). However, it can be associated with acute toxicities related to immune activation, particularly cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Cytokines released from activated immune cells play a key role in their pathophysiology. This study was a prospective analysis of proinflammatory proteins and cytokines in children treated with tisagenlecleucel. Serial measurements of C-reactive protein, fibrinogen, ferritin, IL-6, IL-8, IL-10, IFNγ, and TNFα were taken before treatment and on consecutive days after infusion. The incidence of CRS was 77.8%, and the incidence of ICANS was 11.1%. No CRS of grade ≥ 3 was observed. All complications occurred within 14 days following infusion. Higher biomarker concentrations were found in children with CRS grade ≥ 2. Their levels were correlated with disease burden and CAR-T cell dose. While cytokine release syndrome was common, most cases were mild, primarily due to low disease burden before lymphodepleting chemotherapy (LDC). ICANS occurred less frequently but exhibited various clinical courses. None of the toxicities were fatal. All of the analyzed biomarkers rose within 14 days after CAR-T infusion, with most reaching their maximum around the third day following the procedure.

Inpatient burden and clinical outcomes of cytokine release syndrome in patients with cancer: A National Inpatient Sample study.

11067 Background: Cytokine release syndrome (CRS) is a potentially life-threatening complication commonly seen in patients receiving chimeric antigen receptor (CAR)-T cell therapy, allogeneic stem cell transplant, or immunotherapies. This study aims to evaluate the inpatient burden outcomes of CRS leading to hospitalization in patients diagnosed with cancer. Methods: Hospitalizations for cytokine release syndrome (CRS) were identified using ICD-10 coding from the 2020 National Inpatient Sample (NIS), the largest all-payer inpatient database in the US. Only CRS patients with a co-diagnosis of cancer (identified using the Clinical Classification Software (CCS) coding) were included in this study. The underlying severity of illness index was used to verify CRS grading. Sampling weights were applied to generate nationally representative estimates. Results: In 2020, there were 4,765 hospitalizations coded with CRS. 27.2% of these admissions had a co-diagnosis of cancer (n=1,295) and were included in the final analysis. The top co-diagnoses in the patients with CRS without cancer were COVID-19 infection and sepsis. Hematologic malignancies had the highest incidence amongst cancer types (75.7%), the distribution was as follows: 29.6% with diffuse large B-cell lymphoma, 19.9% with acute lymphoblastic leukemia, 12.8% with multiple myeloma, 12.2% with acute myeloid leukemia, and 7.7% with mantle cell lymphoma. The most common procedures in oncology patients hospitalized with CRS were CAR-T cell therapy (29.3%), chemotherapy (28.6%), stem cell transplant (8.5%), or Blinatumomab bispecific antibody (5.4%). 11.4% of patients with CRS received tocilizumab. Of those that received tocilizumab, 10% were CRS grade 2, 56.7% were grade 3, 33.3% were grade 4. 51.7% of tocilizumab was given in the first 48 hours of admission. A minority of CRS patients required critical care interventions: 12.0% requiring intubation, 5.8% requiring vasopressor support, and 2.7% received dialysis. Overall, 10.4% of all oncology admissions with CRS resulted in death during hospitalization (n=135). Of these deaths, 92.6% were in the extreme severity of illness and 63.0% were CRS grade 4. Those with CRS who died during hospitalization had a significantly longer length of stay (24.6 vs 13.6 days, p<0.001). The overall median hospital charges of a CRS-related admission were $531,692. Conclusions: This study represents the inpatient burden of CRS-related admissions in patients diagnosed with cancer. CRS admissions are commonly seen in patients with hematologic malignancies, those undergoing CAR-T cell or immunotherapies (bispecific antibodies). CRS poses a significant healthcare burden, with average hospital charges being greater than 0.5 million US dollars per admission. About 1 in 10 patients with CRS died during hospitalization with higher mortality likely with severe CRS grades and longer length of stay.

Ambulatory teclistamab administration in patients with relapsed/refractory multiple myeloma.

11146 Background: Teclistamab (Tec) is the first B-Cell Maturation antigen (BCMA)xCD3 bispecific antibody FDA approved for the treatment of relapsed or refractory multiple myeloma (RRMM) in patients who have received ≥4 prior lines of therapy. The phase 1-2 MajesTec-1 study raised concerns for cytokine release syndrome (CRS)/immune effector cell-associated neurotoxicity syndrome (ICANS). 48-hour inpatient observation is recommended for step-up dosing, which imposes financial and logistical burdens. We report our institutional experience with ambulatory Tec administration. Methods: Our inpatient/outpatient (IPOP) hybrid nursing unit is staffed with specialized nurses, advanced practice providers, and attending physicians. Our patients treated in IPOP must live within 1 hour of the hospital and have a 24-hour caregiver. Patients were treated with the recommended step-up dosing schedule. CRS grading and ICE scoring were performed daily. Both CRS and ICANS were graded according to the ASTCT grading systems. We collected toxicities until the second full treatment dose, at which point hospitalization is no longer recommended. Results: In total, 25 patients were treated with Tec between January 2023 to December 2023. The median age was 70 years old (range 59-89), with a median of 6 prior lines of therapy. One patient was dialysis dependent prior to starting Tec. All patients were triple class refractory. Thirteen patients (52%) received prior bone marrow transplant. One (4%) patient received prior anti-BCMA CAR-T therapy. Seventeen patients (68%) required admission during the Tec ramp-up period. CRS was observed in 15 (60 %) patients, all of which were grade I/II events. Fourteen of these patients were hospitalized for CRS. They were admitted for median number of 2 hospital days (range 1-6). Tocilizumab was administered for Grade 2 CRS in 3 patients (12%). ICANS was reported in 4 (16%) patients. Two of those patients developed Grade 2 ICANS which completely resolved with dexamethasone. The median number of admitted hospital days for these patients was 3 days (range 2-49). Neutropenia with ANC < 500 was seen in only 1 (4%) patient. Grade 3/4 infections were seen in 3 (12%) patients during the ramp-up period. Conclusions: Tec administration through an inpatient/outpatient hybrid model is safe and feasible. CRS was common but low grade and short lived. ICANS was observed, but remained low grade and may be attributable to our older patient population. As our center gained experience with the Tec management, we noticed lower rates of admission for low grade CRS. Lower incidences of infections and neutropenia demonstrate that these complications emerge in the months after starting therapy. Future studies will help identify patients who are higher risk for CRS and ICANS during ramp-up treatment and may pave the way for prophylactic interventions and outpatient administration.

Safety and feasibility of outpatient CAR-T therapy: A single center analysis.

e19005 Background: Chimeric Antigen Receptor modified R Cell Immunotherapy (CAR-T) cell products have revolutionized the landscape of treatment of relapsed and refractory (R/R) B-cell malignancies and multiple myeloma. Yet, these therapies emerged with their own challenges, Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) are the most common and serious adverse events. The model of CAR-T cell therapy in the University of Oklahoma is unique as it is designated as an outpatient therapy. Little is known regarding risk factors for hospitalization after CAR-T therapy. Methods: This is a retrospective analysis of all consecutive adult patients who had CAR-T therapy from 9/1/2019 through 9/30/2023 at the University of Oklahoma Health Sciences Center (OUHSC). Inclusion criteria were adult patients with hematologic malignancies who received an FDA approved CAR-T therapy. Exclusion criteria included patients who were younger than 18 at the time of infusion, those who received cellular therapy for solid tumors and those who received investigational CAR-T cell products. Descriptive statistics were created for continuous and categorical variables. Chi-Square analysis and independent samples t-tests were used to measure association with hospital admission and treatment response. Logistic regression was used to explore associations for all covariates with each outcome. SAS 9.4 was used to perform all analysis. An alpha of 0.05 was used to determine significance. Results: A total of 118 patients received outpatient CAR-T/Cellular therapy at OUHSC during the study period with 78 patients meeting the inclusion criteria. The mean age at time of infusion was 58.6 (range=18-85) with most being male (n=46, 59.0%), White (n=63, 80.8%), and overweight/obese (n=50, 64.1%). The majority of patients received anti CD19 CAR-T (n=64, 82.1%) while 18.0% received anti BCMA products. CRS grade 0,1 occurred in 79.5% of patients (n=62) and 79.2% of patients were hospitalized within 30 days after CAR-T therapy (Median day of admission post CAR-T=5.5). Of patients who were hospitalized 26% had grades 2-4 CRS. Complete remission was achieved in 54.7% of patients. We compared the hospitalized and non-hospitalized patients across multiple characteristics, there was no association or predictors of hospitalization found. Albumin was the only predictor for CR. Conclusions: Our study provides data for safety and feasibility of outpatient CAR-T therapy despite potential risks for hospitalization. There are no clear predictors for hospitalizations after CAR-T therapy except for the development of CRS and ICAN. Higher baseline (pre-CAR-T) serum Albumin level was associated with higher odds of achieving CR.

Evaluation of cytokine release syndrome (CRS) in patients with relapsed or refractory multiple myeloma (RRMM) receiving step-up priming doses and longer dosing intervals of elranatamab: MagnetisMM-9.

7522 Background: Elranatamab (ELRA) is a humanized BCMA-CD3 bispecific antibody. In the phase 2 registrational MagnetisMM-3 (MM-3) trial, SC ELRA was given as 2 step-up priming doses (12 mg on C1D1 and 32 mg on C1D4) followed by 76 mg QW in patients (pts) with RRMM. Overall, 56.3% of pts had CRS (grade 2, 14.3%; no grade ≥3). Most events occurred after doses 1 (44.5%), 2 (20.2%), and 3 (5.9%); 0.8% (1 pt) had CRS with doses 4+. Recurrent CRS (>1 event) occurred in 15.1% of pts (Lesokhin Nat Med 2023). Methods: MagnetisMM-9 (MM-9; NCT05014412) is a phase 1/2, open-label, nonrandomized study of ELRA examining an alternative 2-dose step-up priming regimen (4 and 20 mg on C1D1 and C1D4, respectively). Eligible pts had RRMM and were refractory to ≥1 IMiD, ≥1 PI, and ≥1 anti-CD38 antibody. After the priming doses, ELRA 76 mg was given QW for 6 cycles (Part 1) or for 1 cycle followed by 116 or 152 mg Q2W for 5 cycles (Part 2A). The RP2D from Part 2A (152 mg) was evaluated in Part 2B (dose expansion). The rate of grade ≥2 CRS per ASTCT criteria during C1 is the primary endpoint for both parts. Secondary endpoints include evaluation of AEs and PK. Here, we report the overall safety and CRS profile associated with the 4/20 mg priming regimen. Results: For 85 treated pts, median age was 64.0 y; 49.4% were male; 23.5% had EMD; 31.8% had high-risk cytogenetics. Pts had a median of 5.0 (range, 1-12) prior LOTs; 85.9% had triple-class refractory disease. After a median follow-up of 7.4 mo, the most common (>50%) AEs were CRS (63.5%; grade ≥2, 15.3%) and neutropenia (54.1%; all grade ≥2). ICANS occurred in 4.7% of pts (all grade ≤2). The grade ≥2 CRS rate in C1 was 14.1% (90% CI, 8.4-21.9). CRS rates after the first 3 doses are in the the table. For doses 4+, any grade (grade ≥2) CRS was observed in 10.6% (3.5%) of pts overall, 12.1% (3.0%) of pts continuing to receive 76 mg (n=33), 25.0% (0%) of pts receiving 116 mg (n=12), and 5.0% (5.0%) of pts receiving 152 mg (RP2D; n=40). Overall, recurrent CRS was observed in 20.0% of pts. The geometric means (CV%) of free ELRA concentrations 24 h (Cmax-24h) after step-up doses 1 and 2 were 85.64 (48%) and 242.8 (55%). Conclusions: The 4/20 mg step-up priming regimen and alternative dosing schedules resulted in similar safety and incidence of overall and grade ≥2 CRS events vs the regimen used in MM-3 (12/32 mg), with no new safety signals identified. However, the CRS profile in this study differed, with more CRS after doses 2, 3, and 4+ and a higher prevalence of recurrent CRS. The Cmax-24h of free ELRA (CV%) after the priming doses were lower than those in MM-3 (107.4 [47%] and 405.1 [72%], respectively). Thus, the priming regimen used in MM-3 remains the optimal regimen for mitigating CRS. Future analyses of ongoing studies will be used to confirm these results. Clinical trial information: NCT05014412 . [Table: see text]

Metformin and cytokine release syndrome after immune effector cell therapy.

e14535 Background: Cytokine release syndrome (CRS) is the most common complication of chimeric antigen receptor T cells (CAR-T) for hematologic malignancies. We hypothesized that patients undergoing CAR-T therapy who are on metformin will experience a lower incidence or severity of CRS than patients not on this medication. Methods: We evaluated all patients treated with CAR-T at Mayo Clinic Rochester between 1/1/2018 and 1/31/2023, and abstracted relevant clinical and laboratory characteristics to determine the incidence and severity of CRS, PFS as well as OS in patients who were, or were not, on metformin before and during CAR-T therapy for Type 2 diabetes mellitus. We used the Chi-Square test, Mann-Whitney test and the Kaplan-Meier method to analyze data. Results: In the 5-year interval under consideration 237 patients received CAR-T, 168 for non-Hodgkin lymphoma (NHL), and 69 for multiple myeloma (MM). 23 patients (15 NHL and 8 MM) were on metformin at the time of CAR-T. 15 patient developed CRS while on metformin and 175 patients not on metformin (p=0.05). Grade 3 or 4 CRS incidence was 4% in both groups (p=0.41). Of the 153 patients with NHL not on metformin, 121 developed any grade of CRS, while 10 of 15 patients on metformin developed CRS (p=0.268). 4 NHL patients developed CRS Grade ≥3 or higher, while 0 of 15 on metformin developed Grade ≥3 CRS (p=0.237). For the MM patients, the incidence of CRS was 49 patients not on metformin and 5 patients on metformin (p<0.001). 3 MM patients developed CRS Grade ≥3 or higher, while 0 of 8 on metformin developed Grade ≥3 CRS (p=0.346). 12 of 15 patients on metformin with NHL achieved CR compared to 92 of 153 patients not on metformin (p=0.1305). 3 of 8 patients with MM on metformin compared to 24 of 61 patients with MM not on metformin achieved CR or better post CAR-T (p=0.92). Tocilizumab was used in 40% of patients on metformin but in 66% of patients not on metformin (p=0.0016). In NHL patients, PFS from CAR-T infusion was not reached (range: 6.3 to NR) for patients on metformin versus 9.9 months (range: 6.3–19.5) in patients not on metformin (p = 0.3332). In the MM patients, progression-free survival (PFS) from CAR-T infusion was 8.4 months (95% CI: 7.9–not reached [NR]) for patients on metformin and 22.6 months (13.7–NR) for those not on metformin (p = 0.07). Median OS for NHL patients on metformin was not reached (9.766–NR) versus 32.6 months (18.6–NR) for patients not on metformin (p = 0.7022). Median OS was 17 months (95% CI: 8.3 to NR) for patients with MM on metformin vs NR (95% CI: 9.4 to NR) for patients not on metformin (p = 0.2559). Conclusions: In this retrospective study, the co-administration of metformin during CAR-T cell therapy for NHL and MM appears to be associated with a numerically reduced incidence of CRS. The effect appears to be particularly marked in patients with multiple myeloma. Metformin therapy did not seem to affect the response to CAR-T therapy in either NHL or MM.

OPTec: A phase 2 study to evaluate outpatient (OP) step-up administration of teclistamab (Tec), a BCMA-targeting bispecific antibody, in patients (pts) with relapsed/refractory multiple myeloma (RRMM).

7528 Background: Tec is the only approved BCMA×CD3 bispecific antibody with personalized, weight-based dosing for triple-class exposed RRMM. In the MajesTEC-1 study, Tec showed deep, durable responses and a manageable safety profile. Cytokine release syndrome (CRS) occurred in 72% of pts during Cycles 1-2, and 33% of pts had recurrent CRS grade (gr) ≤3 (gr 3, 0.6%). Tocilizumab (Toci) is used to manage CRS. In a separate MajesTEC-1 cohort, pts who received prophylactic Toci (proToci) experienced less CRS, compared with pts who did not (26% vs 72%). Administering the Tec step-up dosing (SUD) regimen in the OP setting may make Tec more accessible, especially at community centers. Therefore, we are investigating whether proToci can reduce the incidence and severity of CRS associated with Tec and facilitate safe OP administration. Methods: This single-arm, non-randomized, multicenter, prospective study (NCT05972135) will evaluate proToci in pts treated with Tec using an OP SUD regimen. The primary endpoint is the overall incidence of CRS. Secondary endpoints include recurrent CRS gr ≥3, and any gr infections, neurotoxicity (NT) including ICANS, neutropenia, and efficacy. Eligible pts are ≥18 years with RRMM and ≥4 prior lines of therapy. Pts with rapidly progressing MM, CNS involvement, active infection, or contraindication to Toci are excluded. Toci 8 mg/kg IV is administered 2 to 4 hours prior to SUD 1 of Tec in an OP setting. The Tec SUD regimen consists of 0.06 mg/kg subcutaneously (SC), 0.3 mg/kg SC 2 to 4 days later, and 1.5 mg/kg SC 1 week after SUD 1. Tec 1.5 mg/kg SC is then given weekly for 12 cycles (28-day) or until MM progression or unacceptable toxicity. Pts with ≥PR after 6 mo can receive 1.5 mg/kg SC biweekly. IVIG is allowed in pts with serum IgG <400 mg/dL. Results: Ten pts will be enrolled at 4 Sarah Cannon / US Oncology community sites in a safety and PK/PD cohort, followed by 40 pts at 12 sites. After the first 6 pts, a Data Review Committee (DRC) meeting was held. Median age was 74 (56 to 83) yrs; half of pts were male. Pts had received a median of 4.5 (4 to 6) prior therapies. One pt with diffuse bony lesions had an SAE of bilateral leg weakness and pain unrelated to Toci or Tec, did not complete the SUD regimen, and died on C1D40 of unknown causes. The other 5 pts completed the SUD regimen per protocol. AEs in >1 pt were fatigue, headache and neutropenia (2 each). Gr 2 hypotension (1 pt) and gr 1 confusion and dizziness (1 pt each) were not felt due to CRS or ICANS. Stopping criteria (gr >3 CRS or NT/ICANS) were not met. The DRC recommended proceeding with enrollment. Conclusions: Initial results indicate that proToci prior to SUD 1 of Tec may mitigate the risk of CRS. Enrollment is ongoing to determine if proToci may make Tec safe to give in an OP setting and increase accessibility in community centers. The full safety cohort will be presented at ASCO. Clinical trial information: NCT05972135 .

Prevalence of adverse events following bispecific antibody therapy in non-Hodgkin lymphoma: A meta-analysis.

e19008 Background: Bispecific antibodies (BsAb) have emerged as a new treatment modality for relapsed/refractory non-Hodgkin lymphomas (R/R NHL). They exert their effect by binding to CD3 on T-cells and CD19 or CD20 on lymphoma cells, activating the T-cell to exert cytotoxic effects against the tumor and normal B-cells. Treatment related adverse events (TRAE) include infections, cytokine release syndrome (CRS), neurotoxicity (ICANS). This meta-analysis was conducted to assess prevalence of TRAEs from prospective clinical trials that evaluated BsAb in R/R NHL. Methods: A systematic review was conducted through PubMed, Embase, Scopus, Web of Science, and Cochrane to identify BsAb clinical trials in NHL through October 2023. Eligible studies included phase I-III trials evaluating BsAb in any type of NHL, either as monotherapy or combination therapy irrespective of prior lines of treatment. Primary outcomes of interest include infection, neutropenia, CRS, and ICANS. All studies were weighted equally. Pooled prevalence estimates of TRAE were calculated using common and random effects models. Heterogeneity tests were performed using Cochran’s Q test. Subgroup analysis examined infection rates in monotherapy versus combination therapy cohorts. Results: After screening 1039 studies, 36 clinical trials with 2162 patients were included. The lymphoma subtypes were diffuse-large B cell lymphoma, follicular lymphoma, and mantle cell lymphoma. The BsAbs included mosunetuzumab (13 studies), epcoritamab (10 studies), blinatumomab (5 studies), glofitamab (5 studies), odronextamab (2 studies), and AFM11 (1 study). The median age of patients was 66 years, and patients had received a median of two prior lines of therapy. Median follow-up duration was 9.1 months. The prevalence of all-grade infections was 35% (95% CI: 0.33-0.38; I2 = 79%). For grade ≥3 infections, the prevalence was 16% (95% CI: 0.14-0.18, (I2 = 77%). There were higher rates of all-grade infections in the combination therapy cohort (41%, 95% CI: 0.36-0.47) compared with the monotherapy cohort (33%, 95% CI: 0.30-0.36). All-grade and grade ≥3 neutropenia occurred in 31% (95% CI: 0.29-0.34; I2 = 80%) and 22% (95% CI: 0.20-0.24, I2 = 61%) of patients. CRS was observed in 45% of patients (95% CI: 0.43-0.48, I2 = 85%). Grade ≥3 CRS occurred in only 2% of patients (95% CI: 0.02-0.03, I2 = 0%, p = 0.99). ICANS occurred in 12% (95% CI: 0.10-0.14, I2 = 90%) while grade ≥3 ICANS was rare, at 3% (95% CI: 0.02-0.03, I2 = 0%, p = 0.99). Conclusions: BsAb is associated with nontrivial rates of infections and neutropenia. The rates of high grade CRS and ICANS are low. The heterogeneity of the findings could be attributed by an underreporting of TRAE and small sample sizes from various studies. These results highlight the need for vigilant practices to diagnose and treat infections early and consideration for antibacterial prophylaxis in this immunocompromised population.

Dynamics of circulating cytokines and chemokines during and after tumor-infiltrating lymphocyte cell therapy with lifileucel in advanced melanoma patients.

9594 Background: Lifileucel, a one-time autologous tumor-infiltrating lymphocyte (TIL) cell therapy, has demonstrated potentially clinically meaningful activity and durable responses in patients with advanced (unresectable or metastatic) melanoma. The regimen includes nonmyeloablative lymphodepletion (NMA-LD) prior to lifileucel infusion, and a short course of interleukin-2 (IL-2) post infusion. The safety profile of the regimen is consistent with the underlying disease and the known safety profiles of NMA-LD and IL-2. Cytokine release syndrome (CRS) is an acute and severe adverse event commonly associated with chimeric antigen receptor T-cell therapy. Here, we report circulating cytokine levels during and after the lifileucel treatment to monitor immune activation, and the dynamics of cytokines and chemokines to explore mechanism of action and potential predictive clinical biomarkers. Methods: The full analysis set of C-144-01 (NCT02360579) includes 153 patients with unresectable or metastatic melanoma who have progressed on checkpoint inhibitors and, if applicable, BRAF/MEK inhibitors. After tumor resection, patients received NMA-LD (cyclophosphamide on Days −7 to −6 and fludarabine on Days −5 to −1) followed by a single lifileucel infusion (Day 0) and up to 6 doses of IL-2 (Days 0-4). Peripheral blood samples were collected at baseline (pre-NMA-LD and pre-lifileucel infusion) and post-lifileucel infusion on Days 1, 4, 14, 42, and 84. Serum cytokine and chemokine levels were measured with BioPlex and included a multiplex panel for IL-6, IL-7, IL-9, IL-10, IL-12, CCL2, CXCL10, IFN-γ, and TNF-α. Plasma samples also were tested for IL-6, IL-15, and IL-7 levels by ELISA. Results: IL-15 levels following NMA-LD peaked at Day 1 and returned to baseline by Day 42. This is consistent with prior reports that NMA-LD increases circulating IL-15 levels, which may promote TIL expansion in the absence of competing endogenous lymphocytes. Similarly, IL-7 and CCL2 also peaked at Day 1. IL-6 did not increase during or after the lifileucel regimen, consistent with absence of severe systemic inflammation including higher grade CRS after lifileucel treatment. There was no difference in cytokine and chemokine levels between responders and nonresponders in the full analysis set. Conclusions: These data support the hypothesized mechanism of action of NMA-LD in the lifileucel regimen. Cytokine levels measured during treatment are consistent with lack of severe systemic inflammation observed in patients treated with lifileucel. Cytokine and chemokine dynamics did not predict for response to lifileucel. Clinical trial information: NCT02360579 .

Clonal Hematopoiesis is Associated With Severe Cytokine Release Syndrome in Patients Treated With Chimeric Antigen Receptor T-Cell (CART) Therapy

Among patients receiving CD19 or B-cell maturation antigen (BCMA) CAR T therapy, inflammation pre- and post-CAR T infusion is implicated in the development of toxicities including cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), and likely contributes to prolonged cytopenias. Clonal hematopoiesis (CH), the clonal expansion of hematopoietic stem cells harboring somatic mutations, has been associated with inflammasome upregulation. Herein, we examined the prevalence of pre-CAR T CH in a predominantly transplant-naïve cohort of recipients with non-Hodgkin lymphoma (NHL) or multiple myeloma (MM), and assessed the relationship between the presence of CH mutations and CAR T-related outcomes including CRS, ICANS, prolonged cytopenia, progression-free survival (PFS), and overall survival (OS). This study included 62 patients with NHL or MM who underwent CD19 or BCMA CAR T therapy from 2017 to 2022 at City of Hope and had available pre-CAR T cryopreserved peripheral blood mononuclear cells (PBMCs). DNA was isolated with QIAamp DNA Mini Kit (Qiagen) from PBMC samples (94% collected <30d of CART infusion), on which we performed targeted exome sequencing (108 pre-defined gene panel with 1000x sequencing depth) to determine the presence of CH (variant allele frequency [VAF] ≥2%). Multivariable logistic regression was used to examine the association between CH and absolute neutrophil count (ANC) recovery at day +30 and +60, maximum grade CRS and ICANS, grade <2 versus 2+, and OS and PFS at 1y. Covariates considered were age at CART, baseline ANC, sex, race, CAR-HEMATOTOX, LDH, bridging therapy (Y/N), and number of prior lines of therapy. Fifteen (24%) patients had at least one pathogenic CH mutation; 2 (13%) had ≥2 CH mutations concurrently. DMT3A mutations were the most common; 29% of mutations had VAFs >10%. Patients with CH were significantly more likely to develop grade ≥2 CRS (60% versus 28%, p = .03) compared to those without CH (odds ratio [OR] 3.9, 95% CI 1.2-13.2; p = .027). Accounting for baseline ANC (which was higher among the CH cohort and associated with delayed ANC recovery, p = .02) patients with CH did not have a significantly different rate of delayed ANC recovery compared to those without CH (adjusted OR 0.37, 95% CI 0.09-1.5; p = .17). There was no association between CH and ICANS, nor with 1y PFS or OS. CH was frequent (24%) in this cohort of CAR T recipients and was associated with a higher risk of development of grade ≥2 CRS after CAR T. Additional validation studies are currently underway, which may set the stage for consideration of pre-CAR T CH as a biomarker for risk stratification towards more proactive CRS prophylaxis. Translational studies could aim to prove a direct relationship between CH-mutated myeloid cells and CRS.

The degree of HLA matching determines the incidence of cytokine release syndrome and associated nonrelapse mortality in matched related and unrelated allogeneic stem cell transplantation with post-transplant cyclophosphamide

Cytokine release syndrome (CRS) occurs frequently after haplo-identical allogeneic stem cell transplantation (alloSCT) with post-transplant cyclophosphamide (PTCy), increasing nonrelapse mortality (NRM) and decreasing survival. Data on CRS in HLA-matched alloSCT are limited and effects of specific HLA-mismatches on CRS development unknown. We hypothesized that in HLA-matched alloSCT increasing degrees of HLA-mismatching influence CRS incidence, NRM and survival. Retrospective analysis of 126 HLA-matched PTCy-alloSCT patients showed that higher degrees of HLA-mismatching significantly increased CRS incidence (26%, 75% and 90% CRS with 12/12, 10/10 and 9/10 matched donors, respectively). Maximum temperature during CRS increased with higher HLA-mismatch. Specific associations between HLA-mismatches and CRS could be determined. Grade 2 CRS and CRS-induced grade 3 fever were associated with significantly increased NRM (p < 0.001 and p = 0.003, respectively) and inferior survival (p < 0.001 and p = 0.005, respectively). NRM was mainly caused by disease conditions that may be considered CRS-induced inflammatory responses (encephalopathy, cryptogenic organizing pneumonia and multi-organ failure).

Growth Factor in the Setting of CAR T-Cell Therapy: To Use or Not to Use

Patients undergoing chimeric antigen receptor (CAR) T-cell therapy may experience side effects including cytokine release syndrome (CRS), immune effector cell–associated neurotoxicity syndrome (ICANS), neutropenia, and infection. Growth factor has historically been used to treat neutropenia; however, its role in CAR T-cell therapy is not well explained. Existing data on the safety and efficacy of growth factor are conflicting. The purpose of this integrative review was to explore the safety and efficacy of growth factor in adult patients with hematologic malignancies undergoing CAR T-cell therapy. A literature review was conducted using PubMed, Cumulative Index to Nursing &amp; Allied Health (CINAHL), and Scopus databases. A total of 2,635 articles were retrieved. Four studies were included that looked at the use of growth factor in the CAR T-cell setting. Safety outcomes evaluated included CRS, ICANS, neutropenic fever and/or infection, and neutropenia duration. Efficacy outcomes evaluated included CAR T-cell expansion and treatment response. The literature suggests that growth factor may not increase CRS prevalence, but may lead to an increased grade of CRS, namely grade 2. Growth factor administration does not have any association with ICANS toxicity, CAR T-cell expansion, or treatment response. Its use may not necessarily lead to decreased infection rates but may shorten the duration of neutropenia. Practice implications for providers working with this unique patient population include using growth factor early in the course of CAR T-cell therapy as treatment to shorten the duration of neutropenia rather than infection prophylaxis.

Infectious complications in pediatric patients undergoing CD19+CD22+ chimeric antigen receptor T-cell therapy for relapsed/refractory B-lymphoblastic leukemia

Chimeric antigen receptor T-cell (CAR-T) therapy is effective in the treatment of relapsed/refractory acute B-lymphoblastic leukemia (R/R B-ALL); however, patients who receive CAR-T therapy are predisposed to infections, with considerable detrimental effects on long-term survival rates and the quality of life of patients. This study retrospectively analyzed infectious complications in 79 pediatric patients with R/R B-ALL treated with CAR-T cells at our institution. Overall, 53 patients developed 88 infections. Nine patients experienced nine infections during lymphodepletion chemotherapy, 35 experienced 41 infections during the early phase (days 0–+ 30 after infusion), and 29 experienced 38 infections during the late phase (day + 31–+ 90 after infusion). Pathogens were identified in 31 infections, including 23 bacteria, seven viruses, and one fungus. Four patients were admitted to the intensive care unit for infection and one died. In a univariate analysis, there were ten factors associated with infection, including tumor load, lymphodepleting chemotherapy, neutrophil deficiency and lymphocyte reduction, cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), etc. In a multivariate analysis, CRS ≥ grade 3 was identified as a risk factor for infection (hazard ratio = 2.41, 95% confidence interval: 1.08–5.36, P = 0.031). Therefore, actively reducing the CRS grade may decrease the risk of infection and improve the long-term quality of life of these patients.

Abstract CT244: HR001, a novel CD19-targeted CAR-T cell therapy for patients with relapsed/refractory non-Hodgkin's lymphoma: primary results of a phase II study (HRAIN01-NHL01-II)

Abstract Background: HR001 is a CD19-targeted CAR-T cell for patients with relapsed and refractory non-Hodgkin's (R/R NHL). Here, we report the primary results of the phase 2 study (HRAIN01-NHL01-II). Methods: HRAIN01-NHL01-II is an open-label, single-arm, and multicenter (17 centers) study in China. It enrolled R/R NHL patients treated with at least two lines of therapy (must-have anthracycline and CD20-targeted agents) or after autologous hematopoietic stem cell transplantation. All patients received a single infusion of HR001 at the 2.0 × 106 CAR+T cells/kg dose. The disease response was evaluated by the independent review committee with Lugano response criteria [2014]. Results: As of May 16th, 2023, 81 R/R NHL patients with ECOG 0-1 at baseline received the infusion HR001 from the Jinshan manufacturing facility [51.9% male; median age 53.4 years (range 23~74); 3.7% CD19 negative; 91.4% diffuse large B-cell lymphoma; 79.0% III-IV of Ann Arbor classification or Lugano] with a median follow-up of 160 days (range 7 to 454). The median time to best response was 30 days (range 28-358). The 3-month, 6 month and best objective response rate (ORR) was 53.1%(95% CI: 41.7-64.3), 45.7%(95% CI: 34.6-57.1) and 74.1% (95% CI: 63.1-83.2) respectively. The 3-month, 6 month and best complete response rate (CRR) was 32.1%(95% CI: 22.2-43.4), 29.6%(95% CI: 20.0-40.8) and 49.4%(95% CI: 38.1-60.7) respectively. Median duration of response (DOR) and progression-free survival (PFS) were 339 days (95% CI: 149-NE) and 176 days (95% CI: 91-NE) respectively. The overall survival (OS) was not reached. The most common treatment-related adverse events (AEs) happened in the hematologic system. The cytokine release syndrome (CRS) occurred in 95.1% of patients, with ≥3 grade CRS observed in 3.7% of patients. Immune effector cell-associated neurotoxicity syndrome (ICANS) happened in 8.6% of patients, without any ≥ 3 grade ICANS reported. The treatment-related mortality was 1.2%. The median time to CAR T-cell peak expansion was 240 hours (120~672) after infusion, median maximum expansion (Cmax) was 17413.9 copies/μg DNA (124.9~136382.2), and median AUC0-28d was 3201014.0 copies/μg DNA (205082.8~18400016.2). Positive tests for the anti-drug antibody (ADA) were noted in 14.8% of patients, while neutralizing antibody (Nab) tests were positive in 3.7% of patients. Among Nab-positive patients, the complete response was maintained until follow-up. Conclusions: Patients with R/R NHL could benefit from the HR001 treatment with satisfactory objective response, durable remission, and favorable safety profile. Citation Format: Yian Zhang, Yuhua Li, Kai Hu, Wuping Li, Hongwei Xue, Qi Deng, Zheng Ge, Liangquan Geng, Xianmin Song, Kang Yu, Hongmei Jing, Bing Chen, Xin Li, Zhimin Zhai, Jianping Shen, Jiang Cao, Qingming Wang, Peng Liu. HR001, a novel CD19-targeted CAR-T cell therapy for patients with relapsed/refractory non-Hodgkin's lymphoma: primary results of a phase II study (HRAIN01-NHL01-II) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT244.