A Study to Learn How Safe AZD6621 is, How Well it Works, and How it Moves Throughout the Body Over Time, in Adult Male Participants With Metastatic Prostate Cancer

This study is looking for men who have prostate cancer that has spread to other parts of their body, even after some other treatments. Your cancer must be a specific type called 'adenocarcinoma' and you must be at least 18 years old.

Your testosterone levels need to be low, either because you've had an operation to remove your testicles or you're already taking medication that lowers testosterone. Importantly, your prostate cancer must have started growing again despite these treatments. We'll also need a recent sample of your tumour tissue, either a fresh one or one that was taken previously.

Doctors will also need to see that your cancer has actually progressed recently, either by looking at blood tests (like PSA levels) or by scans that show new or growing tumours. The specific treatments you've had before might also play a role in whether you can join, depending on which part of the study you might be considered for.

Taking part in this study means you'll receive the experimental drug AZD6621. You'll have regular hospital visits for check-ups, blood tests, and scans to see how you're responding to the treatment and to monitor for any side effects. These assessments will help the study team understand how the drug is working in your body and to keep you safe. The total length of your participation will depend on which part of the study you are in and how you respond to the treatment, but it will involve ongoing check-ups for a period of time.