Sonesitatug Vedotin in Combination With Capecitabine With or Without Rilvegostomig in Participants With Advanced or Metastatic Gastric, Gastroesophageal Junction, or Esophageal Adenocarcinoma Expressing Claudin18.2

The purpose of this study is to evaluate the efficacy and safety of sonesitatug vedotin in combination with capecitabine with or without rilvegostomig in first-line (1L) Claudin18.2 (CLDN18.2)-positive, human epidermal growth factor receptor 2 (HER2)-negative, gastric, gastroesophageal junction (GEJ), and esophageal adenocarcinoma.

• : * Capable of giving signed informed consent * Participant must be 18 years or the legal age of consent in the jurisdiction in which the study is taking place, at the time of signing the informed consent. * Previously untreated histologically documented unresectable, locally advanced, or metastatic gastric, GEJ, or distal esophagus (distal third of the esophagus) adenocarcinoma * Positive CLDN18.2 expression, as determined prospectively by central IHC testing * Confirmed PD-L1 CPS status by central IHC testing and ICI eligibility per investigator judgement is required to determine cohort eligibility as described below: 1. Cohort 1: PD-L1 positive as determined by central IHC testing and the participant is deemed ICI eligible per investigator judgement. 2. Cohort 2: PD-L1 negative as determined by central IHC testing OR the participant is ICI ineligible * ECOG performance status of 0 or 1 with no deterioration to > 1 over the previous 2 weeks prior to baseline at screening and prior to randomisation. * Minimum life expectancy of ≥ 12 weeks. * At least one lesion (measurable and/or non-measurable) that can be accurately assessed by the investigator based on RECIST 1.1. * Adequate organ and bone marrow function as specified in the…

Use the source registry for the full inclusion and exclusion criteria before discussing referral or enrolment.