Published in:
Open Access
01-12-2021 | Acute Lymphoblastic Leukemia | Original Article
CD19 CAR-T cell treatment conferred sustained remission in B-ALL patients with minimal residual disease
Authors:
Wenyi Lu, Yunxiong Wei, Yaqing Cao, Xia Xiao, Qing Li, Hairong Lyu, Yili Jiang, Huan Zhang, Xin Li, Yanyu Jiang, Juanxia Meng, Ting Yuan, Haibo Zhu, Xiaoyuan He, Xin Jin, Rui Sun, Tao Sui, Kaiqi Liu, Mingfeng Zhao
Published in:
Cancer Immunology, Immunotherapy
|
Issue 12/2021
Login to get access
Abstract
The persistence or recurrence of minimal residual disease (MRD) after chemotherapy predicts relapse of B-cell acute lymphoblastic leukemia (B-ALL). CD19-directed chimeric antigen receptor T (CD19 CAR-T) cells have shown promising responses in B-ALL. However, their role in chemotherapy-refractory MRD-positive B-ALL remains unclear. Here we aimed to assess the effectiveness and safety of CD19 CAR-T cells in MRD-positive B-ALL patients. From January 2018, a total of 14 MRD-positive B-ALL patients received one or more infusions of autogenous CD19 CAR-T cells. Among them, 12 patients achieved MRD-negative remission after one cycle of CAR-T infusion. At a median follow-up time of 647 days (range 172–945 days), the 2-year event-free survival rate in MRD-positive patients was 61.2% ± 14.0% and the 2-year overall survival was 78.6 ± 11.0%, which were significantly higher than patients with active disease (blasts ≥ 5% or with extramedullary disease). Moreover, patients with MRD had a lower grade of cytokine release syndrome (CRS) than patients with active disease. However, the peak expansion of CAR-T cells in MRD positive patients showed no statistical difference compared to patients with active disease. Five patients received two or more CAR-T cell infusions and these patients showed a decreased peak expansion of CAR-T cell in subsequent infusions. In conclusion, pre-emptive CD19 CAR-T cell treatment is an effective and safe approach and may confer sustained remission in B-ALL patients with chemotherapy-refractory MRD. The trials were registered at
www.chictr.org.cn as ChiCTR-ONN-16009862 (November 14, 2016) and ChiCTR1800015164 (March 11, 2018).