A Phase 3 Study to Evaluate Petosemtamab Compared With Investigator's Choice Monotherapy in Previously Treated Head and Neck Squamous Cell Carcinoma Patients (LiGeR-HN2)

To be considered for this study, you must be 18 years or older and have a confirmed diagnosis of head and neck squamous cell carcinoma that has either spread or can't be treated with a cure. Importantly, your cancer must have continued to grow despite having received prior treatments, including both anti-PD-1 therapy and platinum-based chemotherapy. If you've only had platinum-based chemotherapy for cancer that was removed or treated locally, your cancer must have come back within six months of your last dose.

Your cancer must be measurable on scans, and you should be in good general health, with a life expectancy of at least 12 weeks. Also, specific parts of your body, like your heart, liver, and kidneys, need to be working well. Doctors will check for other specific medical conditions that might mean this study isn't right for you, such as certain heart problems or untreated brain metastases.

Things that would mean you couldn't join include having uncontrolled spreading to the brain or spinal cord, having had other cancer treatments within the last four weeks, or major surgery within three weeks before the study starts. You also can't have ongoing severe side effects from previous cancer treatments or certain other serious health issues.

If you decide to join this study, you will be randomly assigned to one of two groups: one receiving the new drug, petosemtamab, or one receiving a standard treatment chosen by your doctor. This is like flipping a coin to decide which treatment you get. Both you and your study doctor will know which treatment you are receiving because this is an 'open-label' study. You will have regular visits to the hospital or clinic for your treatment and to have various tests, such as blood tests and scans (like CT or MRI scans), to monitor your health and how the treatment is working. We cannot give specific details here about the frequency of visits or total duration as this will vary depending on your individual response and the treatment you receive, but your study team will explain everything thoroughly. You will continue treatment as long as it is working for you and you are not experiencing unacceptable side effects.