Transcenta Holding Limited (HKG: 6628) announced that it has been granted an invention patent by the China National Intellectual Property Administration (CNIPA) covering the anti-CLDN18.2 antibodies independently developed by the Group and their diagnostic use for detecting CLDN18.2 expression. The relevant antibody is the proprietary Claudin18.2 antibody developed by the Group for the companion diagnostic test of osemitamab (TST001) — reinforcing the intellectual property foundation supporting the global Phase III registrational program of the company’s lead anti-Claudin18.2 monoclonal antibody.
Contents
IP & Program Milestone
| Item | Detail |
|---|---|
| Patent Authority | China National Intellectual Property Administration (CNIPA) |
| Patent Type | Invention patent (granted) |
| Coverage | Independently developed anti‑CLDN18.2 antibodies and their diagnostic use for detecting CLDN18.2 expression |
| Applied Use | Companion diagnostic (CDx) test for osemitamab (TST001) |
| Announcement Date | 12 Oct 2026 |
| Patent Number / Grant Date | Not disclosed |
| Related Clinical Program | Global Phase III TranStar301 – approved to proceed in the United States, China, and Korea |
Drug Profile & Mechanism of Action – Osemitamab (TST001)
- Molecule: Osemitamab (TST001), a high affinity humanized anti-Claudin18.2 monoclonal antibody.
- Target: Claudin18.2 (CLDN18.2), a tight-junction protein with restricted normal-tissue expression that becomes aberrantly exposed on tumor cells in several adenocarcinomas.
- Effector Mechanism: Engineered with enhanced antibody-dependent cellular cytotoxicity (ADCC), aiming to intensify immune-mediated killing of CLDN18.2-expressing tumor cells.
- Regulatory Status (US): Granted Orphan Drug Designation by the U.S. FDA for the treatment of gastric or gastroesophageal junction (GEJ) adenocarcinoma and pancreatic cancer.
- Pivotal Trial: The global Phase III registrational trial TranStar301 evaluates osemitamab in combination with a checkpoint inhibitor and chemotherapy as first-line treatment for Claudin18.2-expressing gastric or GEJ adenocarcinoma — with trial conduct approved by regulators in the United States, China, and Korea.
Companion Diagnostic Strategy – Patent Scope & Role
- Dual-Coverage Patent: The granted invention patent protects both the antibody compositions themselves and their diagnostic use — detecting CLDN18.2 expression in patient samples.
- Proprietary CDx Antibody: The patented antibody is the Group’s proprietary reagent developed specifically for the osemitamab companion diagnostic test, anchoring patient selection to a Transcenta-controlled tool.
- Trial Support Function: The CLDN18.2 CDx is intended to support the advancement of TranStar301, identifying the CLDN18.2-expressing population eligible for first-line therapy in the registrational study.
- Registration & Commercialization Linkage: The CDx is positioned to underpin the future registration and commercialization of osemitamab — since CLDN18.2-targeted therapy requires a matched diagnostic to define the treatable population.
- IP Moat: Securing granted invention-patent protection in China for both the therapeutic antibody class and its diagnostic application strengthens the Group’s exclusivity position across the osemitamab ecosystem.
Disease & Market Context – CLDN18.2 in Gastric Cancer
- Target Biology: Claudin18.2 is a gastric-mucosa tight-junction protein whose tumor-restricted expression pattern makes it an attractive antibody target in gastric, GEJ, and pancreatic adenocarcinomas.
- Validated Class: The therapeutic relevance of CLDN18.2 has been clinically validated in gastric/GEJ cancer by the first approved anti-CLDN18.2 antibody, establishing biomarker-selected targeting as a treatment paradigm. (Class background; not part of the announcement.)
- First-Line Ambition: TranStar301 positions osemitamab in the first-line setting — combining the anti-CLDN18.2 antibody with a checkpoint inhibitor and chemotherapy, a more aggressive combination strategy than antibody-plus-chemotherapy alone.
- Precision Medicine Requirement: Because therapy is restricted to Claudin18.2-expressing tumors, a robust, proprietary CDx is a strategic necessity for trial enrollment, regulatory approval, and commercial deployment.
- Orphan Footprint: FDA Orphan Drug Designations in both gastric/GEJ adenocarcinoma and pancreatic cancer indicate a development strategy spanning multiple CLDN18.2-positive tumor types.
Market Impact & Outlook
- Full-Stack IP Position: With a granted CNIPA invention patent covering antibody and diagnostic use, Transcenta controls both the therapeutic asset and the companion diagnostic reagent — a vertically integrated position in the CLDN18.2 field.
- Global Registrational Pathway: Regulatory approvals to conduct TranStar301 in the US, China, and Korea establish a multi-region route toward first-line gastric/GEJ cancer registration; trial timelines and interim readouts were not disclosed.
- Combination Differentiation: The checkpoint-inhibitor–chemotherapy–antibody triplet distinguishes osemitamab’s first-line strategy within an increasingly competitive CLDN18.2 landscape.
- CDx as Commercial Enabler: Companion diagnostic readiness ahead of registration supports labeling that mandates biomarker-selected use, aligning reimbursement and prescribing from launch.
- Next Steps: Advancement of TranStar301 with CDx-supported enrollment and continued osemitamab development; specific milestones, data readouts, and further IP filings were not detailed in the announcement.
Forward‑Looking Statements
This brief contains forward‑looking statements regarding Transcenta’s anti‑CLDN18.2 patent, the osemitamab (TST001) companion diagnostic, and the TranStar301 Phase III program. Osemitamab is investigational and not approved in any jurisdiction. Actual results may differ due to risks including trial enrollment and outcomes, regulatory review, CDx validation and approval, competitive dynamics in CLDN18.2 targeting, and IP enforcement.-Fineline Info & Tech
