BACKGROUND: Interim analysis of the ENZA-p trial showed improved prostate-specific antigen (PSA) progression-free survival with the addition of lutetium-177 [ METHODS: ENZA-p was a multicentre, open-label, randomised, phase 2 trial done at 15 hospitals in Australia. Participants were men aged 18 years or older who had not previously been treated with docetaxel or androgen receptor pathway inhibitors for metastatic castration-resistant prostate cancer, gallium-68 [ FINDINGS: Between Aug 17, 2020, and July 26, 2022, 79 patients were randomly assigned to enzalutamide and 83 to enzalutamide plus [ INTERPRETATION: The addition of [ FUNDING: The Prostate Cancer Research Alliance initiative (Movember and Australian Federal Government), St Vincent's Clinic Foundation, GenesisCare, RoyMorgan, AdAcAp (a Novartis company), and Astellas.