This is a Study to Learn About How the Combination of the Study Medicines Sigvotatug Vedotin Plus Pembrolizumab Works in People With Non-small Cell Lung Cancer With High Levels of PD-L1.

To join this study, you need to have been diagnosed with non-small cell lung cancer that is either advanced (Stage 3B or 3C and can't be treated with surgery or combined chemo/radiotherapy) or has spread to other parts of your body (Stage 4). A key requirement is that your cancer cells must show high levels of the PD-L1 protein, meaning it's found in 50% or more of your cancer cells. Your cancer also needs to be easily measured, and you should be generally well enough to manage the treatment.

There are also some reasons why you might not be able to join. For example, if you have other serious health conditions, or if you've been diagnosed with another type of cancer in the last three years. If you've had severe lung problems in the past, or if you're allergic to any of the study medicines, you wouldn't be able to take part. The study also needs to make sure your specific type of non-small cell lung cancer doesn't have certain other genetic changes (like EGFR, ALK, or ROS1) that would usually be treated differently.

If you decide to take part in this study, you will visit the clinic regularly. All participants will receive pembrolizumab, a study medicine, through an IV drip (directly into a vein) every 6 weeks. Half of the participants will also receive a second study medicine, Sigvotatug Vedotin, through an IV drip every 2 weeks.

You might receive pembrolizumab for up to about two years. If you're also taking Sigvotatug Vedotin, you can continue this as long as your lung cancer is responding to the treatment. During your clinic visits, the study team will closely monitor your health and how you're responding to the treatment. They will do regular checks and tests to see how you are doing.