Article
作者: Mushtaq, Muhammad Umair ; Sturrock, John ; Nikam, Mugdha Harshakumar ; O'Donnell, David ; Hyzy, Sharon L. ; Lee-Sundlov, Melissa M. ; Keschner, Yonina ; DiPersio, John F. ; Berglund, Eric ; Shah, Nirali N ; Lydeard, John R. ; Mundelboim, Guy ; Canesin, Giacomo ; Magenau, John M ; Whangbo, Jennifer S ; Koehne, Guenther ; Lin, Michelle I. ; Scherer, Julian ; Hu, Jianxin ; Xavier-Ferrucio, Juliana ; Etchin, Julia ; Maakaron, Joseph E. ; Koura, Divya ; Azzi, Jacques ; Lloyd, Deborah M. ; Muffly, Lori S. ; Spink, Kristin ; Beuka, Kelly ; Thosar, Sanjana ; McClune, Brian ; Cooper, Brenda W ; Rimando, Joseph C ; Hummel, Diana ; Vasquez, Michele D ; Suh, Hyung C.
VCAR33, a donor-derived CD33-directed chimeric antigen receptor (CAR) T cell product, was developed to decrease relapse of high-risk acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) after allogeneic hematopoietic cell transplantation (alloHCT). We describe pre-clinical characterization of the VCAR33 construct, which was optimized for long-term anti-tumor surveillance based on killing and persistence assays. Prior to its use in post-alloHCT maintenance, we evaluated safety and efficacy of VCAR33 in a phase 1/2 clinical study for adults with relapsed or measurable residual disease (MRD)-positive CD33+ AML/MDS after alloHCT. Fifteen patients received VCAR33 across 2 arms stratified by disease burden: 7 patients in Arm A (bone marrow blasts ≥ 5%) at dose level 1 (DL1; 1 x 106 CAR+ T cells/kg) and 8 patients in Arm B (bone marrow blasts < 5%) at DL1 (n=5) and DL2 (3 x 106 CAR+ T cells/kg; n=3). The study ended for non-safety reasons before escalation to DL3 (1 x 107 CAR+ T cells/kg) and maximum tolerated dose was not determined. The most common treatment-related adverse event was cytokine release syndrome (93.3%; all < grade 3). Four patients (26.7%) experienced immune cell-associated neurotoxicity syndrome (1 ≥ grade 3) and 1 patient (6.7%) had grade III acute graft-versus-host disease within 28 days of VCAR33 infusion. Fourteen patients (93.3%) had transient VCAR33 expansion. Overall response rate was 20%: 2 patients had complete remission with incomplete count recovery in Arm A and 1 Arm B patient achieved MRD clearance. This allogeneic CAR T product demonstrated acceptable safety and preliminary anti-leukemic activity. ClinicalTrials.gov: NCT05984199.