Nanjing Leads Biolabs Co., Ltd. (HKG: 9887) announced that the Phase 2 clinical study of LBL‑024 (Opamtistomig) in combination therapy as first‑line treatment for locally advanced or metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma has completed the safety lead‑in evaluation and demonstrated positive efficacy signals, supporting progression to the expansion stage — extending the clinical footprint of the world’s most advanced 4‑1BB agonistic bispecific antibody.
Clinical Milestone
| Item | Detail |
|---|---|
| Company | Nanjing Leads Biolabs Co., Ltd. (HKG: 9887) |
| Product | LBL‑024 (Opamtistomig) – anti‑PD‑L1/4‑1BB bispecific antibody |
| Study Phase | Phase 2, combination therapy |
| Setting | First‑line, locally advanced or metastatic gastric / GEJ adenocarcinoma |
| Milestone | Safety lead‑in evaluation completed; positive efficacy signals demonstrated |
| Next Step | Progression to the expansion stage |
| Data Details | Specific efficacy and safety data not disclosed |
Drug Profile & Mechanism of Action
- Molecule: Opamtistomig (LBL‑024), an anti‑PD‑L1/4‑1BB bispecific antibody developed by Leads Biolabs.
- Dual Mechanism: Combines PD‑L1 checkpoint blockade with 4‑1BB (CD137) costimulatory agonism in a single molecule — designed to relieve immune suppression while actively driving T‑cell and NK‑cell costimulation for deeper antitumor immunity.
- Cold‑Tumor Strategy: Evaluated across 14 indications covering multiple major cancer types and “cold tumors” — immunologically inert cancers historically resistant to PD‑(L)1 monotherapy, where 4‑1BB agonism is intended to convert non‑inflamed tumors into responsive ones.
- First‑in‑Class Trajectory: Opamtistomig is expected to become the world’s first approved 4‑1BB antibody drug, the world’s first approved agonistic antibody drug, and the world’s first approved therapy targeting EP‑NEC (extrapulmonary neuroendocrine carcinoma).
- Gastric Cancer Rationale: Advanced gastric/GEJ adenocarcinoma remains a leading cause of cancer death worldwide with limited first‑line options beyond chemotherapy plus checkpoint inhibition — a high‑unmet‑need setting for next‑generation bispecific combinations.
Regulatory Designations & Filing Status
| Jurisdiction | Designation / Status |
|---|---|
| China (NMPA) | Breakthrough Therapy Designation; Marketing Authorization Application accepted (Aug 2026) and included in priority review and approval procedure |
| United States (FDA) | Orphan Drug Designation and Fast Track Designation |
| European Union | Orphan Drug Designation |
| Japan (MHLW) | Orphan Drug Designation |
Market Impact & Outlook
- Imminent First Approval: With the China MAA accepted in August 2026 and placed in priority review, Opamtistomig is positioned to become the world’s first approved 4‑1BB agonistic antibody — a category‑creating event for the costimulatory agonist field that has eluded drug developers for two decades.
- Global Regulatory Momentum: Quadruple‑jurisdiction recognition — NMPA BTD, FDA ODD + Fast Track, EU ODD, and Japan MHLW ODD — signals broad regulatory confidence and paves coordinated international development.
- Pipeline Breadth: Clinical evaluation across 14 indications, including major cancers and cold tumors, gives Leads Biolabs a diversified oncology franchise built on a single differentiated platform.
- Gastric Cancer Opportunity: Positive first‑line signals in gastric/GEJ adenocarcinoma, if confirmed in the expansion stage, would position the combination against the current chemo‑immunotherapy standard in one of oncology’s largest global indications.
- Disclosures: Expansion‑stage enrollment targets, data readout timing, and commercial forecasts were not disclosed in the announcement.
Forward‑Looking Statements
This brief contains forward‑looking statements regarding the clinical development, expansion‑stage progress, regulatory review, and commercialization expectations for Opamtistomig (LBL‑024). Actual results may differ materially due to risks including expansion‑stage efficacy and safety outcomes, NMPA and other regulatory review timelines, competitive dynamics in gastric cancer immunotherapy, and market adoption. Positive early efficacy signals and priority review inclusion do not guarantee eventual approval.-Fineline Info & Tech
