Prostate Cancer MSK 17-259

Sponsor: Memorial Sloan Kettering Cancer Center

Number: MSK 17-259

This research study is a clinical trial designed to test the effects of a new medication called atezolizumab. This medication is being tested in patients who have advanced prostate cancer that has progressed even with treatment or because they are not a candidate for chemotherapy. This includes people that refused chemotherapy.

The standard of care option for patients with Metastatic Castration Resistant Prostate Cancer is Enzalutamide. It works by interfering with the connection between androgens and androgen receptors. This interference may reduce tumor growth. All participants in this study will receive this medication.

The experimental medication, Atezolizumab is an antibody (a protein that your immune system uses to find and neutralize foreign objects such as viruses, bacteria and tumors) that helps your immune system stop or reverse the growth of tumors. This drug has not yet been approved by the U.S. Food and Drug Administration. Early data suggests that the two medications may be beneficial when given together.

Study participants will first be divided into two stages. The first stage will have a combination of both medications to determine the safety of the medication combination. The second stage will begin once the first is complete. This stage will randomly (by chance) assign patients into 2 groups. The first will have a combination of Atezolizumab and Enzalutamide and the second will be Enzalutamide alone.

Who is eligible:

Patients with:

• Metastatic castration Resistant Prostate Cancer after failure of androgen syntheses inhibitor and failure of, ineligibility for, or refusal of a taxane regimen
• Patients must be over the age of 18
• Patients must be physically able to provide self-care
• Patients must have a life expectancy of > 3 months
• Patients must have adequate organ function
• Certain other medical requirements must be met.  See your doctor to be evaluated for this study.