A Study of ASP546C in Adults With Gastroesophageal Cancer, Pancreatic Cancer or Other Solid Tumors

This study will help find the most suitable dose of ASP546C in people with gastric cancer, gastroesophageal junction (GEJ) cancer, pancreatic cancer, and other specific solid tumors. GEJ is where the food pipe (esophagus) joins the stomach. This study is in 2 parts. In both parts of the study, ASP546C will be given once in 3-week cycles. It will be given slowly through a tube into a vein. This is called an infusion. In Part 1, people with gastric cancer or GEJ cancer can take part. They will receive an infusion of either a higher dose or a lower dose of ASP546C. In Part 2, people with pancreatic cancer or who have one of the other solid tumors can take part. Part 2 doesn't include people with gastric cancer or GEJ cancer. All people in this part of the study will receive an infusion of the higher dose of ASP546C. People will visit the clinic on certain days to receive ASP546C and have health checks. The number of visits and checks done during the study will depend on the health of each person and whether they are still receiving infusions of ASP546C.

NCT Number	NCT07488676
Lead Sponsor	Astellas Pharma Global Development, Inc.
Conditions	Gastric or Gastro-esophageal Junction (GEJ) Adenocarcinoma, Pancreatic Adenocarcinoma
Enrollment	150 participants
Start Date	2026-05-04
Primary Completion	2029-07-31 (estimated)
Study Completion	2029-07-31 (estimated)
Updated on ClinicalTrials.gov	2026-07-02