A Study to Test Different Doses of BI 765049 in People With Advanced Cancer of the Colon, Rectum, Stomach, or Pancreas

This study is open to adults with advanced cancer of the colon, rectum, stomach, or pancreas, that is the cancer cannot be removed by surgery or has spread. People can take part in this study if their previous treatment was not successful, or no other treatment exists. The study aims to find the highest dose for the study medicine called BI 765049 that people with advanced cancer can tolerate. Another purpose is to find the most suitable dose and best way of administration of BI 765049 for further clinical development. BI 765049 may help the immune system fight cancer. Participants receive BI 765049 at least once every 3 weeks. Participants may continue to get BI 765049 treatment as long as they benefit from treatment and can tolerate it. Participants in this study also get additional medication before and after treatment with BI 765049 for better tolerability. If participants take this medication at home, they have daily phone visits. Participants regularly visit the study site. The study visits include several overnight stays at the hospital. At the visits, study doctors check participants' health, take necessary laboratory tests, and note any unwanted effects. Unwanted effects are any health problems that the doctors think were caused by the study medicine or treatment. To find the highest dose of BI 765049 that participants can tolerate, researchers look at the number of participants with certain severe health problems. These are severe health problems that happen within the time from when a person first receives the intended target dose, until one week after they receive it for the second time.