KLK3 and prostate carcinoma: In the phase IV Safety Study of Continued Enzalutamide Treatment In Prostate Cancer Patients (PLATO) trial that evaluated 251 patients who were on abiraterone after progression on enzalutamide, the median time to PSA progression (mPSA-P) was 2.8 months, median radiologic progression free survival (rPFS) was 5.7 months, and only 4 patients had PSA decline ≥50% [26,27].