In this work, we report a complete response case of a 69-year-old male with metastatic prostate cancer (initial prostate-specific antigen (PSA)=26.3 ng/mL, Gleason score 3+4=7, cT3a, N0, M1b) treated with triplet therapy comprising leuprorelin + docetaxel (75 mg/m<sup>2</sup>/3 weeks) + darolutamide (1,200 mg/d). The gene discussed is KLK3; the disease is metastatic prostate carcinoma.