A Study of Pasritamig Versus Placebo in Late Line Metastatic Castration-resistant Prostate Cancer (mCRPC)

To be considered for this study, you must be a man aged 18 or older with prostate cancer that has been confirmed through a biopsy. Your cancer must have spread to other parts of your body, like your bones or lymph nodes, and it should no longer be responding to hormone treatments. This spread must be visible on standard scans like CT, MRI, or bone scans.

Your blood test for PSA (Prostate-Specific Antigen) must be 2 nanograms per milliliter (ng/mL) or higher. Your doctor must believe that joining a clinical trial is the best next step for your treatment. You should also have already tried other life-prolonging treatments that your doctor thought were suitable for you and that you had access to.

Specifically, you must have already tried certain established treatments: you should have taken medicines that affect the male hormone pathway (called ARPIs) and found they are no longer working. You should also have had at least two courses of a chemotherapy called a taxane. If you've only had one taxane course, you might still be eligible if other taxane treatments aren't available or your doctor thinks you can't safely have another. You should also have had at least one dose of a specific type of radiation treatment called PSMA-targeted lutetium radioligand therapy, unless your doctor thinks it wasn't suitable for you.

If you decide to take part in this study, you will be given either the study medicine, Pasritamig, or a dummy medicine (placebo). You won't know which one you're receiving, and neither will your doctor, to ensure the results are unbiased. You'll also continue to receive your usual supportive care from your doctors.

Throughout the study, you will have regular visits to the hospital or clinic. These visits will involve various tests and assessments, such as blood tests, urine tests, scans (like CT, MRI, or bone scans) to monitor your cancer, and check-ups with the study doctors and nurses. These appointments are important to see how you're responding to the treatment and to keep an eye on your general health and any side effects you might experience.

The total duration of your participation in the study will depend on how your cancer responds to the treatment and your overall health. You will continue to receive the study drug for as long as it is helping you and you are tolerating it well. Even after you stop the study drug, you will have follow-up visits or phone calls to monitor your long-term health. The exact number and frequency of visits, tests, and duration will be fully explained to you before you agree to join.