A multicenter, randomized phase 2 study evaluating the efficacy and safety of HLX43 (an anti-PD-L1 ADC) in recurrent/metastatic esophageal squamous cell carcinoma.

作者：Linlin Wang, Qi Dang, Yuan Yuan, Yunjian Huang, Jin Zhou, Shoumei Yang, Meili Sun, Shegan Gao, Ruinuo Jia, Leilei Yuan, Lin Zhao, Mudan Yang, Yanqiao Zhang, Jiang Zhao, Xiaoli Hou, Haoyu Yu, Jing Li, Qingyu Wang, Jun Zhu, Jinming Yu · 发表于：Journal of Clinical Oncology · 年份：2026 · DOI：10.1200/jco.2026.44.2_suppl.364 · 研究领域：Mast cells and histamine、CAR-T cell therapy research、Cancer Immunotherapy and Biomarkers

364 Background: Chemotherapy is the predominant treatment option for patients with advanced ESCC following disease progression on first-line chemoimmunotherapy, which has limited efficacy. HLX43 is a novel antibody-drug conjugate targeting the programmed cell death-ligand 1 (PD-L1). Its promising efficacy alongside good tolerability was demonstrated in patients with advanced solid tumors refractory to immune checkpoint inhibitors in a phase 1 trial. This phase 2 study evaluated the efficacy and safety of HLX43 in previously treated recurrent/metastatic ESCC. Methods: Patients with histologically or cytologically confirmed recurrent/metastatic ESCC who progressed on or are intolerant to first-line chemoimmunotherapy were enrolled and randomized 1:1:1 to receive intravenous HLX43 at 2 mg/kg, 2.5 mg/kg, or 3 mg/kg once every 3 weeks. The primary endpoints were investigator-assessed objective response rate (ORR) and progression-free survival per RECIST v1.1. Secondary endpoints included other efficacy endpoints, safety, pharmacokinetics, immunogenicity, and biomarker explorations. Results: As of data cutoff date Aug 26, 2025, 35 patients were randomized to and received HLX43 at 2 mg/kg (n = 11), 2.5 mg/kg (n = 12) and 3 mg/kg (n = 12) groups. Most enrolled patients had an Eastern Cooperative Oncology Group performance status score of 1 (85.7%). Patients received a median line of prior antitumor therapy of 2 (range, 1–4). Among the 7 response-evaluable patients in the 3 mg/kg grou...