4CPS-098 Cytokine release syndrome incidence and management in car-t therapies: a comparative study of axicabtagen ciloleucel and tisagenlecleucel

<h3>Background and Importance</h3> Chimeric Antigen Receptor T-Cell (CAR-T) therapies have significantly improved leukaemias, lymphomas, and multiple myeloma treatments. However, they can induce several adverse effects such as cytokine release syndrome (CRS), which typically manifests its symptoms within first 3–14 days and can be potentially fatal. As a result, early treatment is essential, using drugs such as interleukin-6 inhibitors, among which tocilizumab stands out. <h3>Aim and Objectives</h3> To analyse and to compare cytokine release syndrome incidence following different CAR-T therapies and its resolution through tocilizumab administration. <h3>Material and Methods</h3> Observational, descriptive and retrospective study in a tertiary care hospital including all patients treated with CAR-T therapies (axicabtagen ciloleucel or tisagenlecleucel) from January 2020 to August 2024. Variables were collected from patients’ clinical records(OrionClínic): gender, age, diagnosis, first infusion date; toxicity: yes/no, grade, start/end date and treatment; tocilizumab doses required, ICU stay, and deaths. Quantitative variables are expressed as mean and standard deviation(SD) and qualitative variables as number and percentage(%). The chi-square test was used to compare qualitative variables. Statistical significance was considered when p≤ 0.05. Statistical analysis was performed with SPSS version 23.0. <h3>Results</h3> A total of 50 patients were included. Axicabtagen was administered to 30(60%) patients, 15(50%) women, average age was 55.2(15.2) years and diffuse large B-cell lymphoma(DLBCL) diagnosis. CRS occurred in 29(97%) patients, 27(93%) treated with tocilizumab and 2.2(1.0) average doses administered/patient. Toxicity grade(TG) 1: 15(52%) patients; TG2: 11(38%) patients; TG3: 3(10%) patients. ICU stay: 6(21%) patients. CRS duration: 4.7(2.1) days. On the other hand, tisagenlecleucel was administered to 20(40%) patients, 12(60%) men, average age was 59.7(16.1) years, 18(90%) patients with DLBCL and 2(10%) with acute lymphoblastic leukaemia. CRS occurred in 12(60%) patients, 5(42%) of them treated with tocilizumab, 1.4(0.9) average doses administered/patient. TG1: 9(75%) patients; TG2: 2(17%) patients; TG3: 1(8%) patient. ICU stay: 3(25%) patients. CRS duration: 4.0(1.6)days. The difference between the number of patients who experienced CRS with each treatment was statistically significant. No patient died. <h3>Conclusion and Relevance</h3> This study suggests that patients treated with axicabtagen are more likely to develop CRS and require more tocilizumab doses compared to those treated with tisagenlecleucel. It also suggests that CRS resolution time after tocilizumab administration is very similar in both treatments and TG1 is the most likely TG. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest