Comparison of two treatments for men with metastatic castration-resistant prostate cancer

The TheraP study compared two treatments, (1) lutetium-177 [177Lu]Lu-PSMA-617 and (2) a

chemotherapy agent, cabazitaxel, for men with metastatic castration-resistant prostate cancer that had worsened after chemotherapy with docetaxel. This phase 2 trial, conducted at 11 centers in Australia, focused on patients whose PET imaging showed prostate-specific membrane antigen (PSMA)-positive disease.

Between February 2018 and September 2019, 291 men were registered, and 200 eligible participants were randomly assigned to receive either [177Lu]Lu- PSMA-617 or cabazitaxel. After a median follow-up of about 36 months, no significant difference in overall survival was found between the groups. Safety profiles remained consistent over the longer follow-up period.

Additionally, 27% of initially registered men were excluded due to low PSMA expression or discordant PET findings.

The authors conclude that [177Lu]Lu-PSMA-617 is a viable treatment option alongside cabazitaxel for PSMA-positive metastatic castration-resistant prostate cancer after having previously failed docetaxel therapy. The findings emphasize the importance of PSMA imaging in selecting appropriate therapies, highlighting that PSMA expression levels may influence treatment outcomes.

Lancet Oncol. 2024 Jan;25(1):99-107. doi: 10.1016/S1470-2045(23)00529-6. Epub 2023 Nov 30. PMID: 38043558 DOI: 10.1016/S1470- 2045(23)00529-6