KLK3 and prostate cancer: A U.S. National Cancer Institute (nci)–sponsored Eastern Cooperative Oncology Group randomized phase ii trial was then carried out using two different psa poxvirus vectors in various prime-and-boost regimens: recombinant fowlpox rF–psa (F) alone or combined with rV–psa (V) in patients (n = 64) with biochemical progression after local therapy for prostate cancer.