Clinical outcomes of lutetium-177-PSMA-617 in a racially diverse cohort of patients with metastatic castration-resistant prostate cancer.

BACKGROUND

Lutetium-177 (177Lu)-PSMA-617 is a beta-emitting radioligand approved for treatment of metastatic castration-resistant prostate cancer (mCRPC), despite the underrepresentation of Black patients in pivotal trials. We analyzed outcomes of 177Lu-PSMA-617 in a racially diverse cohort.

METHODS

Retrospective analysis of patients with mCRPC treated with 177Lu-PSMA-617 was conducted at the Emory Winship Cancer Institute. Primary outcomes assessed were progression-free survival (PFS), overall survival (OS), and prostate-specific antigen (PSA) reduction ≥50% (PSA50). Cox proportional hazard models were used for univariate and multivariate OS and PFS, and logistic regression was used for PSA50 analysis.

RESULTS

Among 163 patients treated with 177Lu-PSMA-617, 97 (59.5%) self-identified as White or other racial groups and 66 (40.5%) self-identified as Black. On univariate analysis, Black patients had comparable OS, PFS, and PSA50 responses to non-Black patients, with a trend toward improved outcomes (OS HR: 0.82, P = .446; PFS HR 0.92, P = .655; PSA50 OR = 1.79, P = .088). Multivariate analysis demonstrated a non-significant prolonged PFS and reduction in mortality risk for Black patients (PFS HR: 0.65, P = .106; OS: HR 0.59, HR P-value .081). The odds of a PSA50 response were 2.45 times higher for Black patients (OR = 2.45, P = .027).

CONCLUSIONS

In our racially diverse cohort of patients with mCRPC, Black patients had PFS and OS comparable to non-Black patients, although wide confidence intervals limit definitive conclusions. Black patients had a significantly greater odds of achieving a PSA50 response. Our findings suggest efficacy of 177Lu-PSMA-617 among Black patients in real-world settings and underscore the importance of improved representation in prospective studies.