Givastomig (CLDN18.2 x 4-1BB bispecific antibody)

October 25, 2026: NovaBridge Biosciences (NASDAQ: NBP) reported updated Phase 1b data at ESMO 2026 for givastomig, a CLDN18.2 x 4-1BB bispecific antibody, combined with nivolumab and chemotherapy in HER2-negative first-line metastatic gastroesophageal adenocarcinoma. In 71 patients across the 8 mg/kg and 12 mg/kg cohorts (data cutoff August 6, 2026), the company selected 8 mg/kg for registrational development.

At the 8 mg/kg dose, efficacy-evaluable patients had a 79% objective response rate (23/29), 97% disease control rate (28/29), 15.2-month median duration of response, 16.9-month median progression-free survival, and 17.8-month median follow-up. Activity was reported across CLDN18.2 expression levels, with ORR of 82% in tumors with expression at least 75% and 75% in tumors with expression 1%-74%.

Safety was described as manageable and generally consistent with prior observations; no Grade 4 or 5 treatment-related adverse events were attributed to givastomig, and immune-related adverse events were uncommon other than mostly Grade 2 gastritis.

NovaBridge said ongoing FDA interactions led to alignment on a global registrational/Phase 3 study protocol and design. The program has Orphan Drug and Fast Track designations. Upcoming catalyst: a company webcast on November 2, 2026 to discuss the updated data and registrational development strategy.