Outcomes and risk factors of SARS-CoV-2 omicron variant in B-cell lymphoma patients following CD19 targeted CAR-T therapy.

BACKGROUND: Little was known on infection and mortality rates, still less the risk factors of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant in B-cell lymphoma patients following CD19 targeted chimeric antigen receptor T cell (CAR-T). AIMS: We performed a retrospective multicenter study and analyzed the details of relapsed/refractory (R/R) B-cell lymphoma patients who received CD19 targeted CAR-T heretofore in five cellular immunotherapy centers in China during the omicron wave. MATERIALS & METHODS: One hundred fifty-four patients were enrolled in this study. RESULTS: Among them, 52 patients (33.8%) were uninfected, 74 patients (48.1) had ambulatory mild disease (including nine patients of asymptomatic infection), 22 patients (14.3%) had moderate disease and six patients (3.9%) had severe disease when data collected up. Three patients with severe disease died from COVID-19, the death rate was 1.9% for all enrolled patients, and 2.9% for infected patients. We also found that patients over 60 years old or with diabetes mellitus (DM) tend to develop severe disease (p = 0.0057 and p = 0.0497, respectively). Patients had CAR-T infusion within 6 months also tend to have severe disease (p = 0.0011). In multivariate logistic regression model, CAR-T infusion within 6 months (relative risk (RR) 40.92; confidence interval (CI) 4.03-415.89; p = 0.002) were associated with significantly higher risk of severe disease. CONCLUSION: Through this study, we conclude that the outcome for B-cell lymphoma patients following CD19 targeted CAR-T therapy when facing omicron infection was improved, but aggressive precautionary measures were particularly crucial for patients with high risk factors.