Study of STM-416p Administered to Patients Undergoing Radical Prostatectomy

This trial tests STM-416p, an experimental drug, in men with prostate cancer who are scheduled to have their prostate surgically removed (radical prostatectomy). The drug is given before surgery to see how it affects the tumor. **You may be eligible if...** - You are a male aged 18 or older - You have histologically confirmed prostate cancer with Gleason grade group 2–5 - You are scheduled for radical prostatectomy within 28 days - You have adequate organ and bone marrow function **You may NOT be eligible if...** - You have another invasive cancer other than prostate cancer - Your overall health (ECOG status) is too poor (greater than 2) Talk to your doctor to see if this trial is right for you.