Patients with aggressive B-cell lymphoma receiving CAR T-cell therapy have a low rate of severe infections despite lack of universal antibacterial and antifungal prophylaxis.

OBJECTIVES: Our aim was to describe the frequency and severity of infectious complications after chimeric antigen receptor (CAR) T-cell therapy in patients with large B-cell lymphoma (LBCL).

METHODS: We retrospectively reviewed clinical records of LBCL patients treated with CD19-targeted CAR T-cell therapy from July/2018 to December/2021 at our institution, and identified all infectious episodes from CAR T-cell infusion until disease progression, death or last follow-up.

RESULTS: Overall, 137 patients were included. Thirty six percent had received ≥3 previous lines of therapy and 26% an autologous hematopoietic cell transplantation (auto-HCT). Cytokine release syndrome occurred in 87 (64%) patients. Antibacterial prophylaxis was not used in any patient; only 38% received antifungal prophylaxis. Sixty three infectious events were observed in 41 (30%) patients. Fifty two (83%) of the infectious events had at least one pathogen identified (bacteria [n = 38], virus [n = 11], and fungi [n = 3]). Most of the infectious events occurred during hospitalization for CAR-T treatment. Infection-related mortality was observed in two patients. Independent risk factors for infection included male gender, previous auto-HCT, ≥3 lines of treatment and pre-lymphodepletion neutropenia.

CONCLUSIONS: Infections after CAR T-cell therapy in patients with lymphoma are frequent but generally not severe. A conservative and tailored antimicrobial prophylaxis seems to be a safe approach.