(UroToday.com) Lutetium-177 is a radioligand that when bound to a prostate-specific membrane antigen (PSMA) targeting molecule delivers beta-particle radiation to PSMA-expressing cells and their local microenvironment. This therapy depends on prostate cancer cell surface expression of PSMA, which may be altered by androgen pathway inhibitors. To optimize the utility of this treatment modality in metastatic hormone-sensitive prostate cancer (mHSPC), the PSMAddition trial (NCT04720157) was designed.