Leads Biolabs advances Opamtistomig to expansion phase in hepatocellular carcinoma after positive Phase II efficacy signals
Executive summary: Leads Biolabs announced on August 6, 2026 that its Phase II clinical trial of Opamtistomig (LBL-024), a proprietary PD-L1/4-1BB bispecific antibody, in combination therapy for first-line hepatocellular carcinoma has advanced to the expansion phase following positive efficacy signals. The advancement signals potential clinical promise for a novel immunotherapy approach in hepatocellular carcinoma, a leading cause of cancer-related death globally, and could influence future development strategies in immuno-oncology combinations.
Who is involved: Nanjing Leads Biolabs Co., Ltd. (Stock Code: 9887.HK), the biotechnology company developing Opamtistomig, conducted the Phase II study; no external collaborators or trial sites were specified in the release.
Likely next: Continued enrollment and data collection in the expansion phase of the Phase II trial, with further efficacy and safety readouts expected before potential Phase III planning or regulatory discussions.
Leads Biolabs announced that its Phase II study of Opamtistomig, a PD-L1/4-1BB bispecific antibody, in first-line hepatocellular carcinoma has progressed to the expansion phase based on positive efficacy signals. The development represents a step forward in immuno-oncology combination therapies for liver cancer, a high-mortality malignancy with limited treatment options. No safety concerns or trial modifications were disclosed in the announcement.
Timeline
- — Leads Biolabs’ Opamtistomig (PD-L1/4-1BB Bispecific Antibody) Advances to Expansion Phase in First-Line Hepatocellular Carcinoma Following Positive Efficacy Signals (GlobeNewswire)
Analysis — what this means
Likely next events
- Expected interim efficacy and safety data readout from expansion phase by Q1 2027
- Potential Phase III trial design discussions with regulators by mid-2027 if expansion phase meets predefined endpoints
Sectors affected
- Hepatocellular carcinoma therapeutics
- Bispecific antibody development
- PD-L1/4-1BB immuno-oncology combinations
Regulatory implications
- Future BLA or NDA submission would require demonstration of improved overall survival or progression-free survival versus standard of care (atezolizumab/bevacizumab or durvalumab/tremelimumab) in pivotal trial
- FDA and EMA may require biomarker stratification (e.g., PD-L1 status, AFP levels) for enrollment in later-phase studies
Historical parallels
- Tecentriq (atezolizumab) + Avastin (bevacizumab) approval for hepatocellular carcinoma (IMbrave150 trial, 2020)
- Imjudo (tremelimumab) + Imfinzi (durvalumab) approval for hepatocellular carcinoma (HIMALAYA trial, 2022)