Nanobody-based naturally selected CD7-targeted CAR-T therapy for acute myeloid leukemia

作者：Peihua Lu, Xian Zhang, Junfang Yang, Jingjing Li, Liyuan Qiu, Meiwei Gong, Hui Wang, Jiaqi Chen, Hongxing Liu, Min Xiong, Ying Liu, Lin Wang · 发表于：Blood · 年份：2024 · DOI：10.1182/blood.2024024861 · 被引用次数：49 · 研究领域：CAR-T cell therapy research、Biosimilars and Bioanalytical Methods、CRISPR and Genetic Engineering

ABSTRACT: Approximately 30% of patients with acute myeloid leukemia (AML) express CD7 on their myeloblasts. We have previously demonstrated that single-chain variable fragment (scFv)-based "naturally selected" CD7 chimeric antigen receptor T-cell (NS7CAR-T) therapy shows significant efficacy, with a favorable safety profile in T-cell lymphoid malignancies. Here, we derived dual variable heavy-chain domain of a heavy-chain antibody (dVHH) NS7CAR-Ts that have superior CD7 binding specificity, affinity to their scFv-based counterparts, and improved proliferative capability. In this phase 1 clinical trial, we evaluated the efficacy and safety of nanobody-based dVHH NS7CAR-Ts for patients with CD7+ refractory/relapsed AML. A cohort of 10 patients received dVHH NS7CAR-Ts across 2 dosage levels of 5 × 105/kg and 1 × 106/kg. Before enrollment, patients had undergone a median of 8 (range, 3-17) prior lines of therapy. Seven patients had prior transplants. After NS7CAR-T infusion, 7 of 10 (70%) patients achieved complete remission (CR). The median observation time was 178 days (range, 28-776). Among 7 patients who achieved CR, 3 who relapsed from prior transplants underwent a second allogeneic hematopoietic stem cell transplant (allo-HSCT). One patient remained leukemia free on day 401, and the other 2 died on day 241 and day 776, respectively, from nonrelapse-related causes. Three CR patients without consolidative (allo-HSCT) relapsed within 90 days. All the nonresponders and relapsed...