Study to Assess GTAEXS617 in Participants With Advanced Solid Tumors

This study tests a new experimental drug called GTAEXS617 in people with advanced solid tumors — including head and neck cancer, pancreatic cancer, non-small cell lung cancer, and others — to see if it is safe and effective. **You may be eligible if...** - You have been diagnosed with a confirmed advanced solid tumor (such as head and neck, pancreatic, or lung cancer) - You are able to carry out basic daily activities with little or no assistance (ECOG 0-1) - Your expected survival is greater than 3 months **You may NOT be eligible if...** - You have poor physical function and cannot care for yourself - Your expected survival is 3 months or less - You have not been diagnosed with one of the specific tumor types in the study Talk to your doctor to see if this trial is right for you.