This study is open to adults with advanced cancer that cannot be removed by surgery or have spread to other parts of the body. The purpose of this study is to find the highest and most suitable dose of BI 3968621 that people with advanced cancer can tolerate when taken alone or with ezabenlimab. Another purpose is to find out if taking these medicines can stop tumours from growing or make tumours shrink. In this study, BI 3968621 is given to people for the first time.
The study is done in 3 parts. The parts are called Part A, Part A2, and Part B. Participants get BI 3968621 alone or in combination with ezabenlimab depending on which part they are in. Part A is done to find the highest and the most suitable dose of BI 3968621 that people with advanced cancer can tolerate. Part A2 is done to find out if taking BI 3968621, at certain dose levels, can stop or slow down tumour growth in participants with kidney cancer. Part B is done to find out how BI 3968621 is tolerated when given with ezabenlimab. BI 3968621 is taken daily as tablets. Ezabenlimab is given as an infusion into a vein once every 3 weeks.
Participants can receive study treatment for up to 2 years if they benefit and can tolerate it. During this time, they visit the study site regularly. The number of visits depends on how participants respond to and tolerate the study treatment. Researchers look at the number of participants with certain severe health problems that happen within 3 weeks after the first study treatment. The study doctors check participants' health, take note of unwanted effects, take blood samples, and check how the cancer responds to study treatment.