Infectious complications associated with tocilizumab following chimeric antigen receptor T-cell therapy

Purpose Chimeric antigen receptor (CAR) T-cell therapy has reshaped the outlook for patients with relapsed or refractory hematologic malignancies. In pivotal trials, infections occurred in 19–56% and 42–69% of patients receiving CD19- and B-cell maturation antigen (BCMA)-directed therapies, respectively. Administration of corticosteroids and tocilizumab may further increase the risk of infection. The study purpose is to determine if tocilizumab administration leads to a higher incidence of infection after receiving CAR T-cell therapy. Methods This is a single-center retrospective study analyzing 198 patients who received CAR T-cell treatment from June 1, 2018 through August 21, 2023. Patients who received tocilizumab after CAR T-cell administration were compared to patients who did not. The primary outcome is the incidence of documented infection within 90 days of receiving CAR T-cell therapy. Results During their index admission, 100 patients received tocilizumab after CAR T-cell therapy and 98 patients did not receive tocilizumab. Within 90 days of CAR T-cell administration, the incidence of any infection was 31.6% in patients who did not receive tocilizumab compared to 33% in patients who received tocilizumab (p = 0.837). Positive bacterial cultures occurred in 9.2% of patients who did not receive tocilizumab compared to 20% of patients who did receive tocilizumab (p = 0.031); however, this was not supported with logistic regression (p = 0.076). Conclusion In conclusion, tocilizumab administration did not appear to increase the risk of infection within 90 days after CAR T-cell therapy. These results are limited by the retrospective, single-center nature of the study. A multicenter cohort is recommended to further validate these results.