Levofloxacin Prophylaxis and Infectious Outcomes After Car T-cell Therapy
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background Patients receiving chimeric antigen receptor T-cell therapy are at high risk of febrile neutropenia and bacterial infections. The benefit of levofloxacin prophylaxis remains uncertain and must be balanced against the selection of resistant microorganisms. Objectives To compare episodes of febrile neutropenia, bloodstream infection, and 30-day mortality between patients who received or did not receive levofloxacin prophylaxis. Materials and Methods This retrospective cohort included 56 patients treated with chimeric antigen receptor T cells for non-Hodgkin lymphoma (n = 33), multiple myeloma (n = 19), or acute lymphoblastic leukemia (n = 4). Sixteen patients received levofloxacin prophylaxis and 40 did not. Febrile neutropenia was defined as neutropenic fever treated with antibiotics for at least seven days. Bloodstream infection was defined by a positive blood culture through day-30. Early mortality was defined as death between infusion and day-30, inclusive. Patients without documented death were evaluable if they had at least 30-days of follow-up. Available-case analyses and Fisher’s exact test were used. Results The groups were similar regarding age, sex, performance status, underlying disease, preinfusion disease status, cellular product, and occurrence of cytokine release syndrome. No episodes of febrile neutropenia occurred among the 16 patients receiving prophylaxis, compared with five episodes among 37 evaluable patients without prophylaxis (0.00% vs. 13.50%; p = 0.31). Bloodstream infection occurred in 2/16 (12.50%) patients receiving prophylaxis and 1/26 (3.80%) without prophylaxis (p = 0.55). Thirty-day mortality was 2/16 (12.50%) and 0/26 (0.00%), respectively (p = 0.14), with deaths occurring on days 22 and 30. Three bacterial infections were recorded in the prophylaxis group and two in the nonprophylaxis group. Antimicrobial susceptibility data were unavailable, precluding comparison between susceptible and resistant microorganisms. Discussion A numerically lower proportion of febrile neutropenia episodes was observed with levofloxacin, without statistical significance. No differences were identified in bloodstream infection or early mortality. The small number of events, limited sample size, and unequal follow-up availability constrain the analysis. Fluoroquinolone prophylaxis exerts selective pressure on the microbiota and may promote resistant bacteria, potentially reducing the effectiveness of empirical antimicrobial therapy. The absence of susceptibility data prevented direct assessment of this effect. Conclusion Levofloxacin prophylaxis showed a signal toward fewer episodes of febrile neutropenia, without statistical significance, and was not associated with reductions in bloodstream infection or 30-day mortality. Its use should balance uncertain clinical benefit against the potential risk of antimicrobial resistance. Prospective studies with larger samples and systematic microbiological surveillance are needed.
Institution: AC Camargo Hospital
Language: English
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7223083415