A Phase III Multi-center, Open-label, Sponsor-blinded, Randomized Study of AZD0901 Monotherapy Compared With Investigator’s Choice of Therapy in Second- or Later-Line Adult Participants With Advanced/Metastatic Gastric or Gastroesophageal Junction

The purpose of this study is to learn more about the effectiveness and safety of the study drug AZD0901 compared to standard therapy drugs (Ramucirumab, Paclitaxel, Docetaxel, Irinotecan, and TAS-102). AZD0901 is a type of drug known as an Antibody Drug Conjugate (abbreviated to ADC). AZD0901 recognizes cancer cells by specific protein called Claudin 18.2 (CLDN 18.2). CLDN 18.2 is one of the proteins that is expressed on the surface of gastric cancer cells. AZD0901 binds to CLDN 18.2 on the cancer surface and is taken into the cell where it releases the anti-cancer drug with the goal to stop the cell from reproducing and cause it to die.

Are you Eligible? (Inclusion Criteria)

• Able to provide consent for the trial - Participant must be at least 18 years of legal age - Confirmed unresectable, locally advance or metastatic adenocarcinoma of gastric, GEJ or distal esophagus