Vaccine trials?

My last psa test was 0.27, down from 0.29. Using nomograns my doubling time is between 106 and 124 months - doesn't qualify me for the "zero club" but good enough to just wait and watch.
However, I have come to the conclusion that both hormone treatments and salvage radiation are "blunt instruments" (my urologists phrase for hormone treatment) and that vaccines genetically modified to target prostate cancer cells are the way to go. I have checked into clinical trials and most are for patients whose hormone treatments have failed. My Gleason 9 disqualifies me from some studies and others need a psa score of at least 1.
Does anyone have experience with clinical trials involving vaccines?