A First-in-Human Study Using BDC-4182 as a Single Agent in Advanced Gastric and Gastroesophageal Cancer

This is a first-in-human study testing a new drug called BDC-4182 for people with advanced stomach or gastroesophageal junction (where the stomach meets the esophagus) cancer. The drug targets a protein called Claudin 18.2, which is found on many gastric cancer cells. **You may be eligible if...** - You have confirmed stage 3 (unresectable) or stage 4 (metastatic) gastric or gastroesophageal cancer - You have already tried at least one or two standard treatments, or cannot tolerate them - Your tumor expresses the Claudin 18.2 protein - You have measurable disease on imaging - Your organ function is adequate **You may NOT be eligible if...** - You have never received any prior treatment for your cancer - Your tumor does not express Claudin 18.2 - You have active autoimmune disease, uncontrolled infections, or poor overall health - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.