World's First CLDN18.2 ADC for Regulatory Review: Innovent Biologics Announces IBI343 (arcotatug tavatecan) Met Primary Endpoint in International Phase 3 Study in Advanced Refractory Gastric Cancer and NDA Accepted by China NMPA

SAN FRANCISCO and SUZHOU, China, June 4, 2026 /PRNewswire/ -- Innovent Biologics, Inc. ("Innovent") (HKEX: 01801), a world-class biopharmaceutical company that develops, manufactures and commercializes high quality medicines for the treatment of oncology, cardiovascular and metabolic, autoimmune, ophthalmology and other major diseases, announces that the international multi-center Phase 3 clinical study (G-HOPE-001, NCT06238843) of arcotatug tavatecan (IBI343; Takeda R&D code: TAK-921, an innovative TOPO1i CLDN18.2 ADC) has completed the per-protocol first interim analysis and reached the primary endpoint. Arcotatug tavatecan demonstrated excellent efficacy and a tolerable safety profile in the treatment of advanced gastric cancer. Based on the positive clinical results, Innovent has submitted the new drug application (NDA) for arcotatug tavatecan to the National Medical Products Administration (NMPA) of China, for the treatment of previously treated locally advanced unresectable or metastatic CLDN18.2-positive gastric or gastroesophageal junction adenocarcinoma (G/GEJA) who have received at least two prior systemic therapies. This application has been accepted with priority review.

Arcotatug tavatecan is a biomarker-guided, CLDN18.2-targeted ADC developed as a precision medicine for the treatment of CLDN18.2-expressing cancers. It is designed to selectively deliver a high-potency exatecan payload (TOPO1i) to tumor cells via a cleavable linker, and incorporates Fc silencing to minimize off-tumor toxicities. It is the world's first CLDN18.2 ADC to be submitted for regulatory review.

The G-HOPE-001 study is an international, multicenter, randomized, open-label Phase 3 clinical trial conducted in China and Japan to evaluate the efficacy and safety of IBI343 monotherapy vs. investigator-selected therapy in subjects with previously treated, Claudin 18.2-positive, locally advanced unresectable or metastatic G/GEJA who have received at least two prior systemic therapies. The primary endpoints of the study are PFS and overall survival (OS). The clinical study data are planned to be published in future academic conferences or journals.

Professor Lin Shen, Director of Department of Gastrointestinal Oncology, Beijing Cancer Hospital, said: " We are delighted to see that the pivotal Phase 3 clinical trial of arcotatug tavatecan has been successfully conducted in China and Japan, and achieved its primary endpoint at the first interim analysis. This marks a major breakthrough in targeted precision therapy for gastrointestinal oncology. Meanwhile, the NDA for arcotatug tavatecan has been accepted by the NMPA. The excellent efficacy and manageable safety profile of this product will potentially bring new standardized treatment options and help the adoption of precision diagnosis and treatment for gastrointestinal tumors with targeted therapies."

"Arcotatug tavatecan is a next-generation ADC drug targeting CLDN18.2," said Professor Kohei Shitara, Director of the Department of Gastrointestinal Oncology, National Cancer Center Hospital East. "Clinical study data showed that Arcotatug tavatecan has good overall safety and tolerability, and a low incidence of gastrointestinal-related toxicity. At the same time, it has shown potential and encouraging anti-tumor therapeutic effects in patients with gastric cancer/gastroesophageal junction adenocarcinoma who have high expression of CLDN18.2. The G-HOPE-001 study completed the first interim analysis according to the established study protocol and successfully reached the preset primary endpoint of progression-free survival, which laid a solid foundation for subsequent clinical application."

Dr. Hui Zhou, Chief R&D Officer (oncology pipeline) of Innovent Biologics, said, " Patients with advanced gastric cancer generally have a poor prognosis after initial lines of treatment and are prone to rapid disease progression. There is a lack of effective subsequent treatment options, with median survival of only around six months, highlighting a significant and urgent unmet clinical need. We are excited that the international multicenter Phase 3 study of Arcotatug tavatecan has successfully met its primary endpoint of progression-free survival and that the marketing application in China has been accepted. We look forward to this innovative therapy offering a new and more effective treatment option for patients with advanced gastric cancer."

About gastric/gastroesophageal junction adenocarcinoma

Gastric cancer is one of the most common malignant tumors in the world and is one of the leading causes of death due to cancer worldwide. The 5-year survival rate of patients with metastatic gastric cancer is less than 5%¹. China and Japan are high-incidence areas for gastric cancer². Currently, chemotherapy and immune checkpoint inhibitor therapy combined with fluoropyrimidine and platinum are the standard treatment for patients with advanced metastatic gastric cancer. Systemic therapy has limited efficacy for advanced gastric cancer, especially for third-line and above gastric cancer, the prognosis is usually poor, with few treatment options and short expected survival. The median survival is about half a year³.

CLDN18.2, a tight junction protein specifically expressed in normal gastric mucosa and abnormally highly expressed in gastric cancer and gastroesophageal junction adenocarcinoma (positivity rate up to approx. 80% of cases), is a promising star target for precision treatment of gastric cancer.

About IBI343 (Arcotatug tavatecan)

IBI343 (Arcotatug tavatecan) is a recombinant human anti-CLDN18.2 monoclonal antibody-drug conjugate (ADC) developed by Innovent Biologics. It specifically binds to the tumor cells expressing CLDN18.2, triggering CLDN18.2-dependent internalization of the ADC. Once inside the cell, the cytotoxic payload is released, resulting in DNA damage and ultimately apoptosis of the tumor cells. The released drug can also diffuse across the plasma membrane to reach and kill neighboring cells, resulting in a "bystander killing effect".

Arcotatug tavatecan is currently under NMPA's review and being explored in solid tumor types such as gastric cancer and pancreatic cancer, including:

• Arcotatug tavatecan is under NMPA's priority review for previously treated locally advanced unresectable or metastatic CLDN18.2-positive gastric or gastroesophageal junction adenocarcinoma, based on the positive first interim analysis results from the international multi-center Phase 3 clinical study G-HOPE-001;
• Arcotatug tavatecan is under a Phase 3 clinical study in China for patients with CLDN18.2-positive advanced pancreatic cancer;
• Arcotatug tavatecan is also being explored in Phase 1 clinical studies such as the first-line treatment for patients with gastric cancer and patients with pancreatic cancer.

In October 2025, Innovent Biologics entered into a global strategic partnership with Takeda Pharmaceuticals, which includes granting Takeda exclusive rights for IBI343 (Takeda's R&D code: TAK-921) outside Greater China.

About Innovent Biologics

Innovent is a leading biopharmaceutical company founded in 2011 with the mission to empower patients worldwide with affordable, high-quality biopharmaceuticals. The company discovers, develops, manufactures and commercializes innovative medicines that target some of the most intractable diseases. Its pioneering therapies treat cancer, cardiovascular and metabolic, autoimmune and eye diseases. Innovent has launched 18 products in the market. It has 1 asset under NMPA review, 4 assets in phase 3 or pivotal clinical trials, and 14 more molecules in early clinical stage. Innovent partners with over 30 global healthcare companies, including Eli Lilly, Roche, Takeda, Sanofi, Incyte, LG Chem and MD Anderson Cancer Center.

Guided by the motto, "Start with Integrity, Succeed through Action," Innovent maintains the highest standard of industry practices and works collaboratively to advance the biopharmaceutical industry so that first-rate pharmaceutical drugs can become widely accessible. For more information, visit www.innoventbio.com, or follow Innovent on Facebook and LinkedIn.

Forward-Looking Statements

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These forward-looking statements are based on the Company's management's existing views, assumptions, expectations, estimates, forecasts, and understandings of the future affairs at the time of the statements. These statements are not guarantees for future development and are subject to risks, uncertainties, and other factors, some of which are beyond the control of the Company and are difficult to predict. As a result, actual results may differ materially from those contained in the forward-looking statements as a result of future changes and developments in our business, competitive environment, political, economic, legal, and social conditions.

References

1. Lasithiotakis K, Antoniou SA, Antoniou GA, Kaklamanos I, Zoras O. Gastrectomy for stage IV gastric cancer.  a systematic review and meta-analysis. Anticancer Res. May 2014;34(5):2079-85.
2. Xu B, Wang JM. Epidemiological study of gastric cancer[J]. Chin J Cancer Prev Treat, 2006,13(1): 81-87.
3. Chan WL, Lam KO, So TH, et al. Third-line systemic treatment in advanced/metastatic gastric cancer: a comprehensive review. Ther Adv Med Oncol. 2019;11:1758835919859990.

SOURCE Innovent Biologics