QureBio's Q-1802 Bispecific Antibody Shows 70% Response Rate in Advanced Gastric Cancer Phase II Trial
核心洞察
QureBio's Q-1802, a CLDN18.2 (搜索)/PD-L1 (搜索) bispecific antibody, demonstrated a 70% overall response rate and 11.3-month median progression-free survival in 60 patients with advanced gastric/gastroesophageal junction cancer.
The Phase Ib/II trial showed manageable safety profile with no dose-limiting toxicities observed and only 6.5% permanent discontinuation rate due to adverse events.
Response rates improved to 81.8% in patients with high CLDN18.2 (搜索) expression and PD-L1 (搜索) CPS≥5, supporting advancement to Phase III trials.
QureBio Ltd. (搜索) announced promising Phase Ib/II clinical results for its bispecific antibody Q-1802 in treatment-naïve patients with advanced gastric and gastroesophageal junction cancers, with data to be presented at the 2026 American Society of Clinical Oncology (ASCO) annual meeting.
Strong Efficacy Signals in Advanced Gastric Cancer
The Phase Ib/II trial enrolled 62 eligible patients with CLDN18.2 (搜索)-positive (≥40% tumor cells with 2+/3+ membranous staining), HER2-negative, treatment-naïve, histologically confirmed unresectable locally advanced or metastatic gastric cancer (GC) or gastroesophageal junction (GEJ) cancer. Patients received Q-1802 at doses of 10 mg/kg or 20 mg/kg every two weeks plus standard XELOX (搜索) chemotherapy.
Among 60 efficacy-evaluable patients, the overall response rate (ORR) reached 70.0% (42/60), with a disease control rate (DCR) of 98.3% (59/60) and median progression-free survival (mPFS) of 11.3 months. In the 10 mg/kg cohort, patients with high CLDN18.2 (搜索) expression achieved an ORR of 73.0% (27/37) and mPFS of 11.3 months.
The most encouraging results emerged in a subset of patients with both high CLDN18.2 (搜索) expression and PD-L1 (搜索) combined positive score (CPS) ≥5, where the ORR improved to 81.8% and mPFS extended to 12.2 months among 11 evaluable patients.
Favorable Safety Profile Supports Phase III Advancement
The safety analysis revealed no dose-limiting toxicities (DLT) and the maximum tolerated dose (MTD) was not reached. The most common Q-1802-related grade ≥3 treatment-emergent adverse events included thrombocytopenia (8.1%), neutropenia (6.5%), and anemia, white blood cell decrease, and hypokalemia (4.8% each). Only 6.5% of patients required permanent discontinuation of Q-1802 due to adverse events, and no treatment-related deaths occurred.
Dr. Gong and colleagues concluded that Q-1802 plus XELOX (搜索) demonstrates manageable safety and promising antitumor activity as first-line therapy for CLDN18.2 (搜索)-positive/HER2-negative advanced gastric and gastroesophageal junction cancers, supporting advancement to Phase III trials with Q-1802 10 mg/kg as the recommended dose.
Regulatory Milestone and Mechanism of Action
The Chinese Center for Drug Evaluation (CDE) has recently approved the Phase III trial for Q-1802, marking a significant regulatory milestone for the program.
Q-1802 is a humanized Claudin18.2/PD-L1 (搜索) bispecific antibody designed to eliminate tumors through dual mechanisms involving both innate and adaptive immunity. The antibody activates innate immune responses through antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cell-mediated phagocytosis (ADCP), while simultaneously engaging adaptive immunity involving dendritic cells and T cells. The compound exhibits high affinity and selectivity for its dual targets.
Company Background and Development Pipeline
QureBio Ltd. (搜索), founded in 2017 as a clinical-stage biotechnology company, focuses on developing bispecific antibodies and engineered biopharmaceuticals for cancer, inflammation, and other serious disorders. The company has established proprietary technologies for engineered bio-macromolecules, including innovative platforms for bispecific and trispecific antibodies.
The company has secured funding from multiple investors including Viva Fund, Jundu Investment, Watson Capital, Shenzhen Capital Group, and others, and maintains ongoing collaborations with industrial partners including Precision Scientific and Hengrui Pharmaceuticals.