This study has two parts. In the first part, people will take a new study medicine called TRI 611 by itself every day in treatment cycles that last 28 days. Researchers will test different dose levels to find the safest and best amount of the medicine. The dose may change during the study based on safety results and how people respond.

In the second part, more people will receive dose levels that were already tested in the first part. Participants will be placed into different study groups and continue taking TRI 611 so researchers can learn more about its safety and how well it works.

During the study, doctors will closely monitor participants and check how their cancer responds to the treatment.

Patients with non-small cell (NSCLC) with a specific genetic change called an ALK fusion.

People can join this study if they are 18 years old or older and have a type of lung cancer called ALK positive non small cell lung cancer that has spread or cannot be removed with surgery. Their cancer must have an ALK gene change that is confirmed by testing.

People cannot join if their cancer has certain other genetic changes that may affect how the study medicine works. They also cannot join if their lung cancer has changed into small cell lung cancer, if they have worsening cancer in the brain or spinal cord that is causing symptoms, or if they are receiving other cancer treatments at the same time.

Participants must wait a certain amount of time after previous cancer treatments before starting the study. People with active serious infections, including uncontrolled hepatitis, tuberculosis, AIDS related illness, or COVID 19 that requires treatment, cannot join. Some controlled infections may be allowed if they are stable and being treated.

The purpose of this study is to test a new medicine called TRI 611 in people who have a type of lung cancer called ALK positive non small cell lung cancer. Researchers want to learn if the medicine is safe and find the best dose to use. They will also study how the medicine affects the cancer and look for both helpful effects and side effects. The goal is to learn if TRI 611 could become a useful treatment for people with this type of lung cancer.