Hong Kong-listed Edding Genor Group Holdings Limited (HKEX: 06998) announced on August 6 that the first subject has been dosed in the Phase Ib/II clinical trial of GB268, a PD-1/CTLA-4/VEGF trispecific antibody, in patients with locally advanced unresectable or metastatic breast cancer. The milestone marks the entry of GB268 into breast cancer-specific clinical testing, with the company planning to present Phase I monotherapy data at the European Society for Medical Oncology (ESMO) congress in Q4 2026.
GB268 simultaneously targets PD-1, CTLA-4, and VEGF, combining dual immune checkpoint blockade with anti-angiogenic activity in a single molecule. The trial is enrolling patients with triple-negative breast cancer (TNBC) and hormone receptor-positive/HER2-negative (HR+/HER2-) breast cancer — two subtypes that differ substantially in biology and standard-of-care management but share limited options in later lines. The study, registered with China's National Medical Products Administration (NMPA) under identifier CTR20262740, is designed to enroll up to 270 patients across multiple cohorts.
The open-label, multi-cohort, multi-center study evaluates GB268 as monotherapy, in combination with chemotherapy, and in combination with antibody-drug conjugates (ADCs). Primary endpoints cover safety and tolerability in combination settings — including dose-limiting toxicity (DLT) — and preliminary anti-tumor activity across both monotherapy and combination arms in the respective breast cancer populations. The protocol is designed to span first-line through later-line settings. No efficacy or safety data have been reported at this stage.