Hi Atlantic77. I can't address your specific situation. As a very general rule, the patient (or his insurance) is usually responsible for costs that would be SOC (standard of care) were he not in the trial, and the trial sponsor covers all "experimental" tests/procedures/treatments/medications. Things can vary. If the treatment arms are blinded and, say, the control arm is a SOC medication and the experimental arm is that medication plus X, the sponsor would logically pay for both arms. My experience, however, comes from working in non-urological oncology trials. Other Forum brothers can chime in with their personal experience with PCa -trials expenses.
If the study is up and running, you should call one of the active study Sites (listed at clinical trials.gov) and speak to a research nurse, who can probably tell you the payment basics of that particular trial. Another avenue of inquiry would be to look at the trial details at
clinicaltrials.gov and email one of the principal investigators with your questions. Of course once you go over the (usually very long) enrollment form with the research nurse, all you questions will be answered, but you want answers before you come here. Also read the Inclusion and Exclusion criteria for the study very carefully. You might get here and fail to meet one or more criteria -- for example routine lab values. For some "failures" you can sometimes "correct" the problem (like a lab value that's out-of-range) and retest -- not so for other criteria, e.g. prior treatments/procedures or the results of a genetic (DNA) or genomic (tumor RNA) test.
Hope that helps,
Djin