CAMBRIDGE, Mass. — Takeda announced positive results from a Phase 3 clinical trial of its investigational gastric cancer treatment, arcotatug tavatecan (TAK-921), demonstrating statistically significant improvements in overall survival and progression-free survival among patients with previously treated advanced gastric cancer.
The findings from the G-HOPE-001 study were presented during a late-breaking session at the European Society for Medical Oncology (ESMO) Congress 2026.
The trial evaluated arcotatug tavatecan in patients with advanced gastric or gastroesophageal junction adenocarcinoma whose tumors tested positive for Claudin 18.2 (CLDN18.2), a protein found at elevated levels on certain cancer cells.
According to Takeda, the treatment met both of the study’s primary endpoints, significantly extending survival and delaying disease progression compared with commonly used therapies selected by treating physicians.
Patients receiving arcotatug tavatecan achieved a median overall survival of 10.2 months, compared with 6.9 months among those receiving standard later-line treatments, including irinotecan, paclitaxel or trifluridine/tipiracil.
Median progression-free survival, which measures the time patients live without their cancer worsening, reached 7.1 months in the arcotatug tavatecan group, compared with 3.1 months in the comparison group.
The experimental therapy also demonstrated a higher confirmed objective response rate, with 37.4% of patients experiencing measurable tumor shrinkage, compared with 7.7% among those receiving other treatments.
“People with advanced gastric cancer whose disease has progressed after multiple prior therapies face limited treatment options and poor survival outcomes,” said Kohei Shitara, M.D., Ph.D., a study author and director of the Department of Gastrointestinal Oncology at the National Cancer Center Hospital East in Kashiwa, Japan.
“In the Phase 3 G-HOPE-001 study, arcotatug tavatecan helped patients live longer and significantly extended the time without disease progression compared with commonly used later-line treatments. Together with its manageable safety profile, these findings highlight the potential for arcotatug tavatecan to offer meaningful clinical benefit and become an important new treatment option for patients with advanced CLDN18.2-positive gastric cancer,” Shitara added.
Arcotatug tavatecan is an antibody-drug conjugate designed to deliver a cancer-fighting drug directly to tumor cells expressing CLDN18.2. The therapy combines a targeted antibody with an exatecan-based chemotherapy payload and incorporates technology intended to reduce certain immune-related side effects.
Takeda reported that the treatment’s overall safety profile was generally manageable.
Severe treatment-related adverse events occurred in 47.4% of patients receiving arcotatug tavatecan, compared with 55.9% of those receiving physician-selected treatments.
The most common severe adverse events associated with the experimental therapy included anemia, reported in 20.4% of patients; decreased neutrophil counts, occurring in 17.4%; and reduced white blood cell counts, affecting 11.7%.
Severe gastrointestinal side effects were relatively uncommon, with nausea, vomiting and diarrhea reported in 0.9%, 2.6% and 1.3% of patients, respectively.
Treatment interruptions due to adverse events occurred in 47.4% of patients receiving arcotatug tavatecan, compared with 51.4% in the comparison group. Treatment-related discontinuations were reported in 1.7% of patients receiving the investigational therapy.
The company also disclosed one treatment-related fatal adverse event involving a sudden death of unknown cause in the arcotatug tavatecan group.
The international, randomized, open-label G-HOPE-001 study is being conducted in China and Japan among patients with previously treated, unresectable locally advanced or metastatic gastric or gastroesophageal junction cancer.
Takeda said the findings will support a planned regulatory submission in Japan. In China, its development partner Innovent Biologics has received acceptance of a new drug application for arcotatug tavatecan, which is undergoing priority review by the National Medical Products Administration.
Under a licensing and collaboration agreement with Innovent, Takeda holds worldwide development, manufacturing and commercialization rights to the treatment outside greater China.
“These potentially practice-changing data from G-HOPE-001 not only support the path toward our first regulatory filing and continued global development of arcotatug tavatecan but also mark meaningful progress in translating promising science into new treatment options for patients with a range of challenging CLDN18.2-positive cancers, including gastric and pancreatic cancer,” said Phuong Khanh (P.K.) Morrow, M.D., head of Takeda’s Oncology Therapeutic Area Unit.
Takeda plans to initiate additional global Phase 3 clinical trials evaluating arcotatug tavatecan in gastric and pancreatic cancers, building on ongoing early-stage studies exploring its potential in other CLDN18.2-positive tumors.
Arcotatug tavatecan remains investigational and has not received approval from the U.S. Food and Drug Administration or other regulatory authorities.
