This study is testing a new drug, AB801, to see if it is safe and if it can help treat advanced cancers. Advanced malignancies mean very serious types of cancer that have spread or are hard to treat. The study will help find the best dose of AB801 to use in future research.

People can join if they have certain types of cancer, like lung, colon, or breast cancer, that don't respond to regular treatments. They need at least one tumor that can be measured and need to be in good physical shape. Certain people can't join, like those who have taken live vaccines recently, have certain medical conditions, or are taking specific medicines.

• The study involves taking AB801 alone or with other treatments to see how it works on cancer.
• It will last several weeks, and participants may need to visit the research site often for check-ups.
• Participants will be closely monitored for safety, and their response to the treatment will be evaluated.

This is an important study for those who have run out of other treatment options. Joining this study means working closely with doctors and possibly trying a new treatment.