Infections following chimeric antigen receptor T cell therapy: 2018–2022.

Background Methods Results Conclusion Chimeric antigen receptor (CAR) T‐cell therapy is an emerging therapeutic modality for relapsed and refractory hematological malignancies. Infectious complications following CAR T‐cell therapy are not well defined.This is a retrospective analysis of data on patients who received CAR T‐cell therapy between April 2018 and December 2022 at the Karmanos Cancer Center, Detroit. Patients’ data were collected up to their last known clinic or inpatient follow‐up visit. An infectious episode was defined as any microbiologically proven or clinically documented infection.Seventy‐six patients received therapy with FDA‐approved CAR T‐cell products. Thirty‐three patients (43.4%) had at least one infectious episode. There were 61 infectious episodes during a median follow‐up of 184 (96–340) days. Median duration for the onset of infection was 59 (22–209) days. Bacterial and viral infections occurred in 42.6% and 41% of the infectious episodes, respectively. COVID‐19 was the most common infectious complication (14.8%). Time‐to‐event analysis showed that most infections occurred within the first 100 days. Empirical antibiotic use during Cytokine Release Syndrome/Immune effector Cell‐Associated Neurotoxicity Syndrome (CRS/ICANS) in the absence of documented bacterial infection was reported in 85.7% of patients. <italic>Clostridioides difficile</italic> accounted for 11.5% of all infectious episodes. Five of six patients with <italic>C. difficile</italic> infection had CRS/ICANS and received antibiotics.COVID‐19 and <italic>C. difficile</italic> infection were the most common infections following CAR T‐cell therapy. Most infections occurred within the first 100 days. Empiric antibiotic use and <italic>C. difficile</italic> infection were common in patients with CRS/ICANS, in the absence of documented bacterial infection, thus providing an excellent opportunity for antimicrobial stewardship in this population. [ABSTRACT FROM AUTHOR]