Overall survival in metastatic castration-resistant prostate cancer (mCRPC): A retrospective electronic medical record analysis of men treated with sipuleucel-T in community urology over 14 years.

e17041 Background: Treating mCRPC remains challenging, with limited options for prolonging overall survival (OS). Sipuleucel-T, an autologous prostate-specific antigen (PSA)-targeting cellular immunotherapy (therapeutic vaccine), was FDA-approved in April 2010. We examined the outcomes of treatment for mCRPC since 2010 in SoNaR for Prostate Cancer, the deidentified PPS Analytics/Specialty Networks Uro-oncology electronic medical record (EMR) database that encompasses 90 United States (US) community urology practices with over 3,200 providers. Methods: This multicenter, retrospective study analyzed OS in 2 cohorts of men aged ≥18 years who were diagnosed with mCRPC between January 1, 2010 and May 31, 2024 and treated (Cohort 1) or not treated (Cohort 2) with sipuleucel-T in community urology settings. For the preliminary covariates of race, US region, and age and Gleason group scores at diagnosis, patient characteristics were summarized descriptively, Kaplan-Meier (KM) methods and log-rank tests compared OS, and Cox proportional hazards estimated hazard ratios (HRs). Results: Of a total 11,265 men, 46.9% received sipuleucel-T (Cohort 1). Data from the the sipuleucel-T-treated cohort are described in text; all patients are described in the table. Mean age was 73.4 years, 14% were Black, and 46% were in the Southern US region (Table). At PC diagnosis, the mean Gleason score was 7.3, categorizing 53% as high-risk. At mCRPC diagnosis, the mean PSA level was 49.1 ng/mL (median 6.3 ng/mL). Median OS was 44 months (Table). Among the 4,494 patients of cohort 1 with known status, 28% were still alive 5 years after treatment; their median OS was 97 months. Conclusions: Despite their high-risk disease, patients who received sipuleucel-T had a 44-month median OS, with 28% being alive at 5 years later. This highlights the potential therapeutic benefit of integrating sipuleucel-T into real-world treatment for mCRPC. Further analysis is needed, leveraging the rich nature of this dataset. Supported by Dendreon Pharmaceuticals, LLC. Patient characteristics and outcomes. Overall (n=11,265) Cohort 1Sipuleucel-T (n=5,281) Cohort 2No Sipuleucel-T(n=5,984) P -value, Cohort 1 vs 2 Median age, years 76 74 78 <0.001 Race, % (White/Black/Other) 67/15/19 69/14/17 65/15/21 <0.001 US region, % (Midwest/Northeast/South/West) 25/16/45/14 25/16/46/13 26/16/44/14 0.124 PSA at mCRPC diagnosis (mean/median) 81.1/8.0 49.1/6.3 110.0/10.3 <0.001 Gleason score at PC diagnosis, mean 7.3 7.3 7.2 0.064 Alive at 5 years, % 20% 28% 12% <0.001 KM OS (median, 95% CI), months 33 (32, 34) 44 (43, 46) 24 (24, 25) HR (95%CI), Cohort 1 vs 2 1.7 (1.6-1.8)<0.001 CI, confidence interval.