[Reactivation of cytomegalovirus and its influencing factors in patients with B-lymphocyte malignancy after CAR-T cell therapy].

<b>Objective:</b> This study aimed to analyze cytomegalovirus (CMV) reactivation and its influencing factors in patients with B-lymphocyte malignancy who received chimeric antigen receptor T (CAR-T) cell therapy. <b>Methods:</b> This study retrospectively reviewed patients with B-lymphocyte malignancy who received CAR-T cell therapy in the First Affiliated Hospital of Soochow University from January 2021 to December 2023. The data of patients who underwent CMV-DNA detection and/or pathogen metagenomic sequencing twice or more within 100 days after CAR-T cell therapy were analyzed. The clinical characteristics of the CMV reactivation and non-activation groups were compared. The factors related to CMV reactivation were analyzed with the Chi-square test and nonparametric rank sum test, and the risk factors were examined with Logistic regression. <b>Results:</b> This study included 86 patients, among whom 18 (20.9%) had CMV reactivation, and the median time of reactivation was 20 (1-95) days. All of the 18 patients had CMV viremia, and no CMV disease was observed. Seven patients turned to the latent state after continuing acyclovir antiviral therapy, and 11 patients returned to the latent state after upgrading the antiviral therapy to first-line drugs, including ganciclovir and foscarnet sodium. Six or more courses of anti-tumor treatment before CAR-T cell therapy, allogeneic hematopoietic stem cell transplantation within 2 years before CAR-T cell therapy, non-remission before treatment, and the use of high-dose glucocorticoids and/or tocilizumab were related to CMV reactivation, among which allogeneic hematopoietic stem cell transplantation within 2 years pre-treatment and the use of high-dose glucocorticoids and/or tocilizumab treatment were independent risk factors for CMV reactivation. <b>Conclusion:</b> Patients with B-lymphocyte malignancy who received CAR-T cell therapy have the risk of CMV reactivation, especially for those who received allogeneic hematopoietic stem cell transplantation within 2 years pre-treatment and those who received high-dose glucocorticoids and/or tocilizumab treatment.