Retrospective Analysis of Racial Differences in Treatment Patterns and Prostate-Specific Antigen Responses Among Patients with Prostate Cancer Treated with Relugolix in the Veterans Health Administration
Advances in Therapy, 2025
Introduction
Relugolix is the only oral androgen deprivation therapy (ADT) approved for advanced prostate cancer (PC). Real-world evidence on treatment patterns and prostate-specific antigen (PSA) responses of relugolix, especially as a function of race, remain limited. This study assessed these outcomes and compared differences between Black and White patients.
Methods
Veterans Health Administration data were analyzed to identify male adults with PC who initiated relugolix between December 2020 and December 2023. Adherence to relugolix was assessed for up to 1 year after treatment initiation and was compared between races using generalized linear models. Discontinuation of relugolix, switching to another ADT, and initiating an add-on PC treatment were assessed using Kaplan-Meier analyses and compared between races using Cox regressions. PSA responses during relugolix treatment, including ≥ 50% and ≥ 90% decline from baseline and achieving < 0.2 ng/mL, were assessed among ADT-naïve patients.
Results
A total of 507 patients were identified (141 Black and 313 White patients). During the first 12 months of treatment, both races had > 90% adherence to relugolix with no significant differences between them. During follow-up (median 10.7 and 12.6 months for Black and White patients, respectively), 27.0% Black and 21.1% White patients discontinued relugolix; 9.2% Black and 3.8% White patients switched to another ADT; and 11.3% Black and 10.5% White patients initiated an add-on PC treatment. Among ADT-naïve patients, 87.2% Black and 87.2% White patients achieved PSA decline ≥ 50% from baseline; 69.2% and 64.1% achieved ≥ 90% decline; 51.3% and 47.4% achieved PSA < 0.2 ng/mL.
Conclusion
Adherence to relugolix was very high during the first year of treatment. These data support that in the real world, patients can adhere to relugolix with PSA responses on par with clinical trials regardless of race. Black patients were more likely to discontinue or switch to another ADT than White patients, but the reasons for this require further study.
Authors
Freedland SJ, Ramaswamy K, Kavati A, Gao W, Razo JF, Cole M, Li B, Yang H, Guo T, Chen G, McKay RR