Vorinostat and 177Lu-PSMA-617 for the Treatment of PSMA-Low Metastatic Castration-Resistant Prostate Cancer

This phase II trial tests how well vorinostat works in treating patients with prostate-specific membrane antigen (PSMA)-low castration-resistant prostate cancer that has spread from where it first started (primary site) to other places in the body (metastatic) (mCRPC). Prostate cancer that has not spread to other parts of the body (localized) is typically treated through surgery or radiotherapy, which for many men is curable. Despite definitive local therapy, cancer that has come back after a period of improvement (recurrent) disease develops in 27-53% of men. Often this is detected by measurement of prostate-specific antigen (PSA) without visible evidence of metastatic disease. Lutetium Lu 177 vipivotide tetraxetan (177Lu-prostate specific membrane antigen \[PSMA\]-617) is a new small molecule PSMA-targeted radioactive therapy that has been approved by the Food and Drug Administration for the treatment of adult patients with PSMA-positive mCRPC who have been treated with androgen receptor inhibitors and taxane-based chemotherapy. Vorinostat is used to treat various types of cancer that does not get better, gets worse, or comes back during or after treatment with other drugs. Vorinostat is a drug which inhibits the enzyme histone deacetylase and may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving vorinostat and 177Lu-PSMA-617 may kill more tumor cells in in patients with PSMA-low mCRPC.

NCT Number	NCT06145633
Lead Sponsor	Fred Hutchinson Cancer Center Collaborators: Novartis, Institute for Prostate Cancer Research (IPCR), National Cancer Institute (NCI)
Conditions	Castration-Resistant Prostate Carcinoma, Metastatic Prostate Adenocarcinoma, Stage IVB Prostate Cancer AJCC v8
Enrollment	15 participants
Start Date	2024-09-18
Primary Completion	2026-12-30 (estimated)
Study Completion	2027-12-30 (estimated)
Updated on ClinicalTrials.gov	2026-08-06