DURHAM, NC — For men with homologous recombination repair (HRR) deficient metastatic castration-resistant prostate cancer (CRPC), PARP inhibitors can be life-prolonging therapies. Estimates of PARPi benefit in diverse patient populations are limited, however.
A new study led by the Durham, NC, VA Healthcare System and Duke University described patterns of PARPi use and outcomes in mCRPC in the nationwide VHA, which includes a high proportion of Black patients, otherwise underrepresented in published PARPi studies.
The retrospective cohort included mCRPC patients prescribed a PARPi in the VHA. Researchers collected demographic, clinical, pathologic and genomic data, conducting survival analysis and gathering descriptive statistics. Gleason score, prostatectomy, stage, number of therapies, age, prostate-specific antigen (PSA) at diagnosis and at PARPi start were taken into account.
In the study published in Clinical Genitourinary Cancer, overall survival (OS), defined as time from PARPi initiation to death or censoring, was the primary outcomes, with other outcomes including percent PSA change, time on PARPi and genomics-stratified OS.1
Among 597 veterans included, 79.4% were white and 20.6% Black. Compared to white men, Black men were younger (62 vs. 68 years), had higher PSA at diagnosis (19.0 vs. 8.8 ng/mL), longer time from diagnosis to PARPi initiation (90.6 vs. 69.4 mos) and more commonly received PARPi as ≥4th-line therapy (43.9 vs. 31.4%).
The results indicated that median OS from PARPi initiation was 13.7 months (95% CI, 12.6-15.8), with no statistically significant difference between Black and white patients after IPTW (P = 0.95). “The most common HRR variants were BRCA2, ATM, or CDK12,” the researchers explained. “In exploratory analyses, BRCA altered patients had longer OS than non-BRCA (15.9 vs. 12.6 mos). Black patients with CDK12 alterations had longer OS than those without (21.4 vs. 12.2 mos).”
The authors concluded, “In this real-world cohort of veterans with mCRPC, Black patients had higher-risk disease and later PARPi use, pointing to the need to address equity in practice patterns. After adjustment for baseline differences, survival from PARPi start was similar by race. Further research on CDK12 mutations and PARPi response, especially in Black patients, is warranted.”
- Bitting RL, Tseng CL, Giagtzis A, Wyatt AW, McNair C, Kim H, Halabi S, Giri VN. Patterns of Poly(ADP-Ribose) Polymerase Inhibitor Use and Overall Survival in United States Veterans With Prostate Cancer. Clin Genitourin Cancer. 2026 Aug 5:102640. doi: 10.1016/j.clgc.2026.102640. Epub ahead of print. PMID: 42660761.