Background and Importance In the context of B-cell non-Hodgkin lymphomas, the use of CAR T-cell therapy offered new treatment possibilities. The evolution of these therapies can improve the treatment arsenal and patients’ life expectancy. However, some patients experience treatment failure: the identification of predictors can be crucial for a cost-effective use of this therapy.

Aim and Objectives The purpose of this analysis was to evaluate the correlation between some possible predictive factors and outcome after tisagenlecleucel infusion in patients with diffuse B-cell lymphoma. A retrospective observational study was conducted on a cohort of 35 patients treated with tisagenlecleucel from clinical practice in an Italian Oncologic Institute from December 2019 to August 2023. Patients were evaluated based on their response to the therapy in terms of overall response rate over an 18-month period following infusion. The analysed factors included age, gender, development of cytokine release syndrome and its grade, tocilizumab administration, steroid administration, lymphocyte count at the time of leukapheresis, lymphocyte count at day 14 and day 30 post-infusion, c-reactive protein at day 0, peak of c-reactive protein within 14 days post-infusion, ferritin at day 0, peak ferritin within 14 days, previous therapy lines, previous autologous marrow transplantation, disease stage, bridge therapy received.

Material and Methods Factors that could influence response were analysed by stratified analysis dividing patients into responders (complete remission, partial remission) and non-responders (death and progression) at 18 months; Mann-Whitney U test for continuous variables and Fisher’s exact test for categorical variables were used. Univariate logistic regression was used to assess the independent contribution of each factor on the probability of response to therapy. Statistical significance was considered for a value of p<0.05.

Results Elevated baseline levels of c-reactive protein and ferritin increase the risk of therapy failure. Higher ferritin peaks within 14 days also increase the risk of failure. Higher lymphocyte expansion at day 30 is associated with a better response; previous autologous marrow transplantation correlates with a better response.

Conclusion and Relevance The patient‘s inflammatory status before therapy should be carefully evaluated: elevated levels of inflammatory markers are associated with therapy failure. Previous autologous marrow transplantation correlates with a better response; the analysis of factors that can predict the possibility of treatment failure is important.

Conflict of Interest No conflict of interest.