Median Baseline Prostate-specific Antigen Research Articles

A phase 2, single-arm trial evaluating 131I-PSMA-1095 targeted radioligand therapy for metastatic castration-resistant prostate cancer.

Metastatic castration-resistant prostate cancer (mCRPC) remains uniformly lethal. Prostate specific membrane antigen (PSMA) is a transmembrane glycoprotein overexpressed in prostate cancer. 131I-PSMA-1095 (also known as 131I-MIP-1095) is a PSMA-targeted radioligand which selectively delivers therapeutic radiation to cancer cells and the tumor microenvironment. We conducted a single-arm, phase 2 trial to assess efficacy and tolerability of 131I-PSMA-1095 in mCRPC patients who had exhausted all lines of approved therapy. All patients underwent 18F-DCFPyL PET and 18F-FDG PET to determine PSMA-positive tumor volume, and patients with >50% PSMA-positive tumor volume were treated with up to four doses of 131I-PSMA-1095. The primary endpoint was the response rate of prostate specific antigen (PSA). Secondary endpoints included rates of radiographic response and adverse events. Overall and radiographic progression-free survival were also analyzed. Eleven patients were screened for inclusion and nine patients received 131I-PSMA-1095. The median baseline PSA was 162 µg/l, and six patients demonstrated a >50% PSA decrease. One patient demonstrated a confirmed radiographic response. Median overall survival was 10.3 months, and median progression-free survival was 5.4 months. Four patients experienced adverse events of grade 3 or higher, the most frequent being thrombocytopenia and anemia. 131I-PSMA-1095 is highly active against heavily-pretreated PSMA-positive mCRPC, significantly decreasing tumor burden as measured by PSA. Adverse events, mainly hematologic toxicity, were not infrequent, likely related to off-target irradiation. This hematologic toxicity, as well as a higher logistical burden associated with use, could represent relative disadvantages of 131I-PSMA-1095 compared to 177Lu-PSMA-617.

Real-world retrospective study of prostate-specific antigen and safety assessment with darolutamide plus androgen deprivation therapy for metastasis hormone-sensitive prostate cancer.

ARASENS has demonstrated the efficacy and safety for darolutamide (DARO) with androgen deprivation therapy (ADT) plus docetaxel in metastasis hormone-sensitive prostate cancer (mHSPC). There is a lack of reports for DARO with ADT in mHSPC though the regimen is used in clinical from time to time. Moreover, recent studies have supported the importance of early and rapid prostate-specific antigen (PSA) reduction, which correlates with reduced disease progression and improved survival in patients with mHSPC. This study aims to evaluate PSA reduction as a primary endpoint for DARO with ADT in the treatment of mHSPC and to evaluate the real-world short-term PSA control of DARO with ADT from two leading medical centers in China. We retrospectively reviewed the clinical records of patients with mHSPC receiving ADT and DARO (600 mg, b.i.d.). The collection of data spanned from March 1, 2022, to July 31, 2023. The main observation indicators were PSA level and drug-related adverse events (AE) after medication. PSA levels were closely monitored prior to treatment initiation and at 2-week intervals, as well as at 1, 3, and 6 months after the initiation of treatment. We also conducted an analysis to determine the proportion of patients achieving a PSA reduction of 50% or more (PSA50) and 90% or more (PSA90) as well as the percentage of patients with a notable decrease in PSA level to 0.2 ng/mL and PSA nadir of ≤0.02 ng/mL. Fifty-one patients were included in the study, with a median age of 73 years. At diagnosis of HSPC, the majority of patients had a Gleason score ≥8 (n=40, 78.40%) and a median baseline PSA level of 88 ng/mL. Approximately 45.1% (n=23) of patients had a Charlson Comorbidity Index over 1 and were receiving one or more nontumor-related treatments. The median follow-up time was 9.3 months (range, 1.16-15.8 months). The median reductions in PSA levels compared to baseline were 84.37%, 91.48%, 94.67% and 99.81% at 2 weeks, 1 month, 3 months and 6 months after administration of DARO with ADT, respectively. The median time to PSA50, PSA90, significant PSA reduction (PSA <0.2 ng/mL), and PSA nadir (PSA <0.02 ng/mL) was 0.97, 1.27, 1.98, and 2.08 months, respectively. AE mainly included fatigue (two patients) and arm pain (one patient), all of which were grade I or II AE. No grade III or AE were observed. For treating prostate cancer, DARO with ADT has good early efficacy, demonstrating prompt and substantial control of PSA levels, with a favorable safety profile.

The survival outcomes for men with metastatic castration-resistant prostate cancer (mCRPC) with and without homologous recombination deficiencies (HRD) treated with radium-223: Princess Margaret Cancer Centre (PMCC) experience.

179 Background: Radium-223 (223Ra) is a radiopharmaceutical that emits alpha particles and specifically targets bone metastases in mCRPC, where it has been shown to improve overall survival (OS). Since 223Ra induces double-strand DNA breaks, we hypothesized that patients with HRD may exhibit heightened sensitivity to 223Ra, resulting in improved survival outcomes compared to patients without HRD. Methods: This retrospective analysis was performed in men with mCRPC and bone metastases, with and without HRD, treated with 223Ra at PMCC. Demographics and disease characteristics were collected. Germline and/or somatic DNA sequencing data were identified. OS and progression free survival (PFS) were calculated using the Kaplan–Meier method; differences in outcomes were assessed using the log-rank test. Alkaline phosphatase (ALP) and prostate specific antigen (PSA) responses were calculated at 12 weeks post 223Ra treatment. Results: We identified 40 mCRPC patients who had germline and/or somatic DNA sequencing and received 223Ra between December 2015 and May 2022. The median age at the start of 223Ra was 76.5 (range: 66.5-80.8), and ECOG was 0/1 (75%). A total of 29 (72.5%) patients received 233 Ra following abiraterone or enzalutamide treatment while 10 (25%) received 233 Ra post docetaxel. Overall, 22 (54%) received ≥4 cycles of ²²³Ra. Median baseline PSA was 58.6 (range: 25.2-143) and median baseline ALP was 109 (range: 71.8-200). Germline/somatic HRD mutations were found in 9/40 (22.5%) patients (BRCA2 [n=6], CHEK2 [n=2], CDK12 [n=1]). Baseline characteristics were well balanced between HRD and non-HRD groups. With median follow up of 13.7 months, the median OS of HRD group vs. non-HRD group was 24 months (95%CI: 14-not evaluable [NE]) vs. 12 months (95%CI: 7-22); p=0.038). The median PFS of HRD group vs. non-HRD group was 5.7 months (95%CI: 3-NE) vs. 3.3 months (95%CI: 2.5-13.4); p=0.74). The median time to the next treatment of HRD group vs. non-HRD group was 4.2 months (95%CI: 3.1-NE) vs. 3.75 months (95%CI: 3.5-13.5); p=0.89. ALP response was 66.7% of HRD group vs. 58.1% of non-HRD group; p=0.72. PSA response was 33.3% of HRD group vs. 9.7% of non-HRD group; p=0.11. For all patients with ALP response, the three years survival probability of HRD group vs. non-HRD group was 33% vs. 11%; p=0.03. Conclusions: While the number of patients included in our review was small, our analysis suggested that patients with HRD may have a slight improvement in OS after 223Ra treatment. Validation in a prospective dataset is required, and whether HRD status has implications for other radiopharmaceuticals such as lutetium-177 remains to be seen.

Actinium-225-PSMA radioligand therapy of metastatic castration-resistant prostate cancer (WARMTH Act): a multicentre, retrospective study

Actinium-225 (225Ac) prostate-specific membrane antigen (PSMA) radioligand therapy (RLT) is a novel therapy for metastatic castration-resistant prostate cancer (mCRPC). We aimed to report the safety and antitumour activity of 225Ac-PSMA RLT of mCRPC in a large cohort of patients treated at multiple centres across the world. This retrospective study included patients treated at seven centres in Australia, India, Germany, and South Africa. We pooled data of consecutive patients of any age and Eastern Cooperative Oncology Group performance status with histopathologically confirmed adenocarcinoma of the prostate who were treated with one or more cycles of 8 MBq 225Ac-PSMA RLT administered intravenously for mCRPC. Previous lines of mCRPC treatment included taxane-based chemotherapy, androgen-receptor-axis inhibitors, lutetium-177 (177Lu) PSMA RLT, and radium-223 dichloride. The primary outcomes were overall survival and progression-free survival. Between Jan 1, 2016, and May 31, 2023, 488 men with mCRPC received 1174 cycles of 225Ac-PSMA RLT (median two cycles, IQR 2-4). The mean age of the patients was 68·1 years (SD 8·8), and the median baseline prostate-specific antigen was 169·5 ng/mL (IQR 34·6-519·8). Previous lines of treatment were docetaxel in 324 (66%) patients, cabazitaxel in 103 (21%) patients, abiraterone in 191 (39%) patients, enzalutamide in 188 (39%) patients, 177Lu-PSMA RLT in 154 (32%) patients, and radium-223 dichloride in 18 (4%) patients. The median follow-up duration was 9·0 months (IQR 5·0-17·5). The median overall survival was 15·5 months (95% CI 13·4-18·3) and median progression-free survival was 7·9 months (6·8-8·9). In 347 (71%) of 488 patients, information regarding treatment-induced xerostomia was available, and 236 (68%) of the 347 patients reported xerostomia after the first cycle of 225Ac-PSMA RLT. All patients who received more than seven cycles of 225Ac-PSMA RLT reported xerostomia. Grade 3 or higher anaemia occurred in 64 (13%) of 488 patients, leukopenia in 19 (4%), thrombocytopenia in 32 (7%), and renal toxicity in 22 (5%). No serious adverse events or treatment-related deaths were recorded. 225Ac-PSMA RLT shows a substantial antitumour effect in mCRPC and represents a viable therapy option in patients treated with previous lines of approved agents. Xerostomia is a common side-effect. Severe bone marrow and renal toxicity are less common adverse events. None.

Clinical consequences of a genetic predisposition toward higher benign prostate-specific antigen levels

Prostate-specific antigen (PSA) levels are influenced by genetic variation unrelated to prostate cancer risk. Whether a genetic predisposition to a higher PSA level predisposes to a diagnostic work-up for prostate cancer is not known. Participants were 3110 men of African and European ancestries ages 45-70, without prostate cancer and with a baseline PSA < 4ng/mL, undergoing routine clinical PSA screening. The exposure was a polygenic score (PGS) comprising 111 single nucleotide polymorphisms associated with PSA level, but not prostate cancer. We tested whether the PGS was associated with a: 1) PSA value>4ng/mL, 2) International Classification of Diseases (ICD) code for an elevated PSA, 3) encounter with a urologist, or 4) prostate biopsy. Multivariable Cox proportional hazards models were adjusted for age and genetic principal components. Analyses were stratified by age (45-59 years, and 60-70 years old). Association estimates are per standard deviation change in the PGS. The median age was 56.6 years, and 2118 (68%) participants were 45-59 years. The median (IQR) baseline PSA level was 1.0 (0.6-1.7) ng/mL. Among men ages 45-59, the PGS was associated with a PSA > 4 (hazard ratio [HR]=1.35 [95% CI, 1.17-1.57], p=4.5×10-5), an ICD code for elevated PSA (HR=1.30 [1.12-1.52], p=8.0×10-4), a urological evaluation (HR=1.34 [1.14-1.57], p=4.8×10-4), and undergoing a prostate biopsy (HR=1.35 [1.11-1.64], p=0.002). Among men ages 60-70, association effect sizes were smaller and not significant. A predisposition toward higher PSA levels was associated with clinical evaluations of an elevated PSA among men ages 45-59 years. National Institutes of Health (NIH).

Comparative real-world (RW) evidence on darolutamide (Daro), enzalutamide (Enza), and apalutamide (Apa) for patients (Pts) with nonmetastatic castration-resistant prostate cancer (nmCRPC) in the United States: DEAR.

5097 Background: Novel androgen receptor inhibitors (ARIs) are recommended for pts with nmCRPC. Daro has a distinct structure with low blood-brain barrier penetration which may lead to a lower risk of central nervous system-related adverse events (AEs) and minimal risk of AEs commonly associated with ARIs. DEAR is the first study comparing RW utilization, outcomes, and AEs between daro and enza/apa in nmCRPC pts. Methods: This retrospective chart review cohort study uses electronic medical records from the PPS network of US urology practices. Eligible pts had nmCRPC, no prior novel hormonal therapy, and initiated first ARI treatment (index date) between 8/2019-3/2022. We describe the % of pts who discontinued initial ARI treatment (DISC), % who progressed to metastasis (PROG), and % with AEs. A comparative analysis was performed between daro and enza/apa using Cox proportional hazards models for time to DISC/time to PROG, adjusting for observed baseline (BL) factors. Results: 870 pts were included (daro/enza/apa, n=362/382/126). Median age (80/79/80 y), median BL prostate-specific antigen (PSA) doubling time (6.8/6.4/7.4 mo), other BL characteristics, and median follow-up (22.2/22.7/23.3 mo) were similar for daro/enza/apa. A lower % of pts had a DISC event on daro vs enza/apa (30.4 vs 40.8/46.0) or a PROG event (17.7 vs 28.3/27.8) during the study period. Multivariate analyses adjusting for BL factors showed that pts on daro had a lower risk of DISC and PROG over time vs enza/apa. A lower % of pts on daro had AEs vs enza/apa (24.9 vs 29.3/30.2). Conclusions: Overall, a lower % of pts discontinued initial ARI treatment, progressed to metastasis, or had AEs on daro vs enza/apa. In analyses adjusting for observed BL factors, pts on daro had considerably lower risk of DISC and PROG vs enza/apa. This study confirms daro’s strong efficacy and favorable tolerability profile in a RW setting. The longer treatment duration seen with daro may be associated with a lower risk of progression to mCRPC vs enza/apa. [Table: see text]

Darolutamide observational (DAROL) study in patients with nonmetastatic castration-resistant prostate cancer: Second interim analysis.

e17095 Background: In ARAMIS (NCT02200614), darolutamide (DARO) significantly improved metastasis-free survival (MFS) by ~2 years (HR 0.41, 95% CI 0.34–0.50) and reduced the risk of death by 31% (HR 0.69, 95% CI 0.53–0.88) compared with placebo in men with nonmetastatic castration-resistant prostate cancer (nmCRPC), with a favorable tolerability profile. The ongoing DAROL study (NCT04122976) aims to understand the real-world safety and effectiveness of DARO in patients (pts) with nmCRPC. We report results from the pre-planned second interim analysis (IA). Methods: DAROL is a global, open-label, single-arm, non-interventional study in pts aged ≥18 years with confirmed nmCRPC for whom the decision to be treated with DARO is decided pre-enrollment. The primary endpoint is safety, including incidence, severity, and frequency of treatment-emergent adverse events (TEAEs). Secondary endpoints are patient demographics and disease characteristics, treatment duration, MFS, overall survival (OS), time to prostate-specific antigen (PSA) progression, and PSA response. Primary and secondary endpoints are reported after 300 pts completed ≥6 mo of treatment. All treated pts were assessed for safety while efficacy was evaluated in pts who did not violate any eligibility criteria and had ≥1 post-baseline assessment (cut-off October 11, 2022). Results: Of the 300 treated pts, the percentage enrolled in North America/Europe/Asia Pacific/Latin America was 45%/30%/25%/ &lt; 1%, respectively. Median age was 80 years; 51% had a reported Gleason score &gt; 7; 92% had a reported ECOG performance status of 0/1. Median baseline (BL) PSA was 3.9 ng/mL (range 0–248.0), with 21% of pts reporting PSA &lt; 2 ng/mL. Median BL PSA doubling time (PSADT) was 5.3 mo (range 0–36.2), with 42% of pts reporting PSADT &gt; 6 mo. At the data cut-off, median follow-up time was 14.8 mo (interquartile range [IQR] 10.9–19.3) and median treatment duration was 13.4 mo (IQR 9.3–17.8). The incidences of TEAEs and DARO-related TEAEs were generally low (Table), consistent with the safety profile of DARO reported in ARAMIS. Fatigue occurred in ≥5% of pts. For the 263 pts eligible for efficacy analysis, median time to PSA progression was 17.6 mo (95% CI 13.2–19.0); MFS/OS data remain immature. PSA declines from baseline of ≥30%, ≥50%, and ≥90% at any time were observed in 80%, 76%, and 54% of pts, respectively. Conclusions: In the DAROL second IA, under real-world conditions, DARO continued to show a favorable safety profile, consistent with the clinical profile of ARAMIS, with no new safety signals. Clinical trial information: NCT04122976 . [Table: see text]

Efficacy and safety of darolutamide in Chinese patients with metastatic hormone-sensitive prostate cancer (mHSPC): A subpopulation analysis of the phase 3 ARASENS study.

e17076 Background: Darolutamide (DARO) is an androgen receptor inhibitor approved in China for the treatment of nonmetastatic castration-resistant prostate cancer (CRPC). In the global ARASENS trial, DARO significantly increased overall survival (OS) vs placebo (PBO) in patients (pts) with mHSPC. The efficacy and safety of DARO in the Chinese subpopulation of ARASENS are reported here. Methods: In this randomized, double-blind phase 3 trial, 1305 pts with mHSPC were randomized 1:1 to receive DARO 600 mg orally twice daily or PBO, in combination with androgen-deprivation therapy (ADT) and docetaxel. The primary endpoint was OS. Results: In mainland China, 202 pts were randomized to the DARO group (n = 104) or the PBO group (n = 98). Demographics and baseline characteristics were well balanced between treatment groups and comparable to the overall ARASENS population, except for a slightly higher proportion of pts with Gleason score ≥8, higher proportion with metastatic disease at diagnosis, and higher median baseline prostate-specific antigen (PSA) in Chinese pts vs the overall population. The risk of death was reduced by 36% (HR 0.64, 95% CI 0.41–0.99) with DARO vs PBO in Chinese pts (Table). The key secondary endpoint time to CRPC (HR 0.32, 95% CI 0.20–0.50) and the exploratory endpoint time to PSA progression (HR 0.22, 95% CI 0.13–0.37) also favored DARO. In the DARO group, 81% of pts had a maximum PSA decline of ≥90% from baseline (PSA90) at week 12, while 88% had PSA90 and 71% reached PSA &lt; 0.2 ng/mL at any time. Incidences of treatment-emergent adverse events (TEAEs) in Chinese pts were similar between treatment groups and comparable to the overall population. The most common grade 3/4 TEAE in Chinese pts was neutropenia (DARO 64%, PBO 62%), a known toxicity of docetaxel; grade 3/4 febrile neutropenia occurred in 4.0% of Chinese pts compared with 7.6% in the overall population. Conclusions: In the ARASENS subpopulation of Chinese pts with mHSPC, DARO + ADT + docetaxel showed favorable efficacy and safety vs PBO + ADT + docetaxel: OS and clinically relevant secondary endpoints favored DARO vs PBO, and the incidences of TEAEs were similar in the two treatment groups. These results are consistent with the findings reported for the overall population in ARASENS. Clinical trial information: NCT02799602 . [Table: see text]

Definitive local therapy for T4 prostate cancer associated with improved local control and survival.

To evaluate patients with clinical (c)T4 prostate cancer (PCa), which represent both a heterogenous and understudied population, who often present with locally advanced disease and obstructive symptoms causing significant morbidity and mortality. We analysed whether receiving definitive local therapy influenced symptomatic and oncological outcomes. Retrospective analysis of 154 patients with cT4 PCa treated at a single institution in 1996-2020. Systemic therapy with or without local treatment (surgery, radiotherapy [RT], or both). Uni- and multivariate analyses of associations between clinicopathological features (including obstructive symptoms) and receipt of local therapy on overall survival (OS) and disease control were done with Cox regression. The median follow-up time was 5.9 years. Most patients had adenocarcinoma (88%), Gleason score 9-10 (77%), and median baseline prostate-specific antigen (PSA) of 20 ng/mL; most (54%) had metastatic cT4N0-1M1 disease; 24% regionally advanced cT4N1M0, and 22% localised cT4N0M0. Local therapies were RT (n = 44), surgery (n = 28), or both (n = nine). Local therapy was associated with improved OS (hazard ratio [HR] 0.3, P < 0.001), longer freedom from local recurrence (HR 0.39, P = 0.002), less local progression (HR 0.41, P = 0.02), fewer obstructive symptoms with progression (HR 0.31, P = 0.01), and less death from local disease (HR 0.25, P = 0.002). On multivariate, local therapy was associated with improved survival (HR 0.58, P = 0.02), and metastatic disease (HR 2.93, P < 0.001) or high-risk pathology (HR 2.05, P = 0.03) was associated with worse survival. Definitive local therapy for cT4 PCa was associated with improved symptomatic outcomes and survival even among men with metastatic disease. Pending prospective evaluation, these findings support definitive treatment with local therapy for cT4 disease in select cases.

Role of radiomic analysis of [18F]fluoromethylcholine PET/CT in predicting biochemical recurrence in a cohort of intermediate and high risk prostate cancer patients at initial staging.

To study the feasibility of radiomic analysis of baseline [18F]fluoromethylcholine positron emission tomography/computed tomography (PET/CT) for the prediction of biochemical recurrence (BCR) in a cohort of intermediate and high-risk prostate cancer (PCa) patients. Seventy-four patients were prospectively collected. We analyzed three prostate gland (PG) segmentations (i.e., PGwhole: whole PG; PG41%: prostate having standardized uptake value - SUV > 0.41*SUVmax; PG2.5: prostate having SUV > 2.5) together with three SUV discretization steps (i.e., 0.2, 0.4, and 0.6). For each segmentation/discretization step, we trained a logistic regression model to predict BCR using radiomic and/or clinical features. The median baseline prostate-specific antigen was 11ng/mL, the Gleason score was > 7 for 54% of patients, and the clinical stage was T1/T2 for 89% and T3 for 9% of patients. The baseline clinical model achieved an area under the receiver operating characteristic curve (AUC) of 0.73. Performances improved when clinical data were combined with radiomic features, in particular for PG2.5 and 0.4 discretization, for which the median test AUC was 0.78. Radiomics reinforces clinical parameters in predicting BCR in intermediate and high-risk PCa patients. These first data strongly encourage further investigations on the use of radiomic analysis to identify patients at risk of BCR. The application of AI combined with radiomic analysis of [18F]fluoromethylcholine PET/CT images has proven to be a promising tool to stratify patients with intermediate or high-risk PCa in order to predict biochemical recurrence and tailor the best treatment options. • Stratification of patients with intermediate and high-risk prostate cancer at risk of biochemical recurrence before initial treatment would help determine the optimal curative strategy. • Artificial intelligence combined with radiomic analysis of [18F]fluorocholine PET/CT images allows prediction of biochemical recurrence, especially when radiomic features are complemented with patients' clinical information (highest median AUC of 0.78). • Radiomics reinforces the information of conventional clinical parameters (i.e., Gleason score and initial prostate-specific antigen level) in predicting biochemical recurrence.

Nadir Prostate-specific Antigen as an Independent Predictor of Survival Outcomes: A Post Hoc Analysis of the PROSPER Randomized Clinical Trial.

This post hoc analysis of PROSPER evaluated the relationship between depth of PSA decline and clinical outcomes in enzalutamide-treated men with nonmetastatic castration-resistant prostate cancer. PROSPER was an international, randomized, double-blind, placebo-controlled, phase 3 trial that demonstrated significantly improved metastasis-free survival and overall survival with androgen deprivation therapy plus enzalutamide vs placebo. A total of 905 enzalutamide-treated men were included in this post hoc analysis. Metastasis-free survival (primary endpoint) and overall survival (secondary endpoint) were evaluated for 4 mutually exclusive subgroups defined by PSA decline: <50% (reference); ≥50% to <90%; ≥90%, nadir ≥0.2 ng/mL; and ≥90%, nadir <0.2 ng/mL. Medians and 95% confidence intervals were determined using a 12-month landmark analysis; hazard ratios and P values were based on an unstratified Cox proportional analysis model. In enzalutamide-treated men, PSA declines of <50%, ≥50% to <90%, ≥90% with nadir ≥0.2 ng/mL, and ≥90% with nadir <0.2 ng/mL were associated with median metastasis-free survival in months (95% confidence intervals) of 22.1 (14.8-not reached), 34.2 (29.4-not reached), 36.6 (33.4-not reached), and not reached, respectively, and overall survival in months (95% confidence intervals) of 40.8 (31.7-44.9), 54.4 (49.0-67.0), 64.3 (63.4-not reached), and not reached, respectively. There was a statistically significant correlation between greater depth of PSA decline and improved clinical outcomes, suggesting a previously underappreciated relationship between changes in PSA levels and clinical outcomes in nonmetastatic castration-resistant prostate cancer.

Impact of 68Ga-PSMA PET/CT in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with enzalutamide.

48 Background: 68Ga prostate specific membrane antigen positron emission tomography/computed tomography (68Ga-PSMA PET/CT) is a highly sensitive diagnostic tool to detect prostate metastatic sites even at low levels of Prostate Specific Antigen (PSA). We evaluated the impact of 68Ga-PSMA PET/CT in patients treated with enzalutamide as first-line therapy for mCRPC. Methods: In an observational prospective study, 67 consecutive mCRPC patients were treated with enzalutamide 160 mg once daily in first-line for mCRPC. 68Ga-PSMA PET/CT was performed at baseline, after 3 months, during follow-up and at PSA/clinical progression. Patients were evaluated on a monthly basis for serological PSA response and safety. We measured at baseline the sum of metabolic total volume (SMTV), mean standardized uptake volume (SSUVmean), maximum standardized uptake volume (SSUVmax) and total lesion activity (STLA), which is the product of SMTV and SSUVmean, for a maximum of 20 lesions. These parameters together with baseline PSA level, Eastern Cooperative Oncology Group performance status (ECOG PS), Gleason Score (GS) and age were analyzed by univariate and multivariate Cox regression models as potential predictors of progression-free survival (PFS) and overall survival (OS). Results: At the moment of the present analysis, 58 mCRPC patients were considered fully evaluable. The median age was 75 years (range, 47-91), ECOG PS was 0 in 47 cases (81%), 1-2 in 11 (19%), GS was &lt;8 in 22 (38%), 8-10 in 36 (62%), the median baseline PSA was 2.66 µg/L (range 0.09-197). We observed a median SMTV of 5.73 cm3, median SSUVmax of 44.85, median SSUVmean of 25.80 and median STLA of 59.66. At the median follow-up of 52 months, median PFS was 28.9 months (95% CI 16.3-43.6), median OS was not reached (95% CI 36.8-not reached). In univariate analysis, SSUVmax and STLA were significant for PFS (p=0.015 and p=0.001, respectively) and OS (p=0.026 and p=0.019, respectively), while SSUVmean was significant only for OS (p=0.028). On multivariate analysis, STLA only remained significant for PFS (p&lt;0.001) and OS (p=0.026). Conclusions: The assessment of mCRPC by 68Ga-PSMA PET/CT before starting enzalutamide was associated with longer median PFS and OS compared to prior studies using standard imaging only. STLA, expression of both volume and intensity of 68Ga-PSMA uptake, appeared the strongest parameter able to predict PFS and OS.

Real-world prostate-specific antigen (PSA) response and disease progression among patients with non-metastatic castration-resistant prostate cancer (nmCRPC) initiated on apalutamide (APA).

69 Background: For patients with nmCRPC, APA with androgen deprivation therapy is an important therapeutic option with demonstrated efficacy in improving metastasis-free survival (MFS), and other clinical outcomes. However, there is limited real-world information on these outcomes among patients with nmCRPC treated with APA. This study describes PSA response and MFS among patients with nmCRPC treated with APA in the United States as compared to the SPARTAN registrational trial. Methods: Clinical data from 2/2017 to 4/2022 collected from 77 community-based urology practices were used to evaluate patients with nmCRPC who received ≥1 APA dispensation (index date being the date of first dispensation). Patients were excluded if they had previously used another next-generation antiandrogen or had &lt;12 months of pre-index clinical activity. PSA response was evaluated while on treatment and was defined as a post-index ≥90% decline (PSA90) in PSA from baseline (using the closest PSA value within 13 weeks prior to or on the index date) and was reported in patients with ≥1 post-index PSA test result by 3 months, 6 months, 12 months and overall. Disease progression was evaluated as MFS and defined as the time from index date to the occurrence of metastasis or death, whichever occurred first. Disease progression was described using Kaplan-Meier (KM) analysis by 6-month increments up to 24 months post-index. Results: A total of 406 patients with nmCRPC (mean age 78.8 years, 73% white, mean baseline PSA 9.0 ng/mL) were identified. Among 96 patients with available data, the mean (median) baseline PSA doubling time was 9.9 (7.5) months. The mean (median) treatment duration was 434 (305) days. PSA90 rates were 40% by 3 months, 51% by 6 months, 56% by 12 months, and 58% overall. KM rates for MFS were 95% at 6 months, 90% at 12 months, 82% at 18 months, and 75% at 24 months. PSA response and MFS for real-world patients were consistent with those observed from the SPARTAN trial. Conclusions: This real-world study of patients with nmCRPC demonstrates that APA treatment resulted in early, deep PSA responses, consistent with the SPARTAN trial. Moreover, MFS observed in the real-world was similar to that of the SPARTAN trial. [Table: see text]

The Role of [18F]F-Choline PET/CT in the Initial Management and Outcome Prediction of Prostate Cancer: A Real-World Experience from a Multidisciplinary Approach.

Initial staging of prostate cancer (PCa) is usually performed with conventional imaging (CI), involving computed tomography (CT) and bone scanning (BS). The aim of this study was to analyze the role of [18F]F-choline positron emission tomography (PET)/CT in the initial management and outcome prediction of PCa patients by analyzing data from a multidisciplinary approach. We retrospectively analyzed 82 patients who were discussed by the uro-oncology board of the University Hospital of Ferrara for primary staging newly diagnosed PCa (median age 72 (56–86) years; median baseline prostate specific antigen (PSA) equal to 8.73 ng/mL). Patients were divided into three groups based on the imaging performed: group A = only CI; group B = CI + [18F]F-choline PET/CT; group C = only [18F]F-choline PET/CT. All data on imaging findings, therapy decisions and patient outcomes were retrieved from hospital information systems. Moreover, we performed a sub-analysis of semiquantitative parameters extracted from [18F]F-choline PET/CT to search any correlation with patient outcomes. The number of patients included in each group was 35, 35 and 12, respectively. Patients with higher values of initial PSA were subjected to CI + PET/CT (p = 0.005). Moreover, the use of [18F]F-choline PET/CT was more frequent in patients with higher Gleason score (GS) or ISUP grade (p = 0.013). The type of treatment performed (surgery n = 33; radiation therapy n = 22; surveillance n = 6; multimodality therapy n = 6; systemic therapy n = 13; not available n = 2) did not show any relationship with the modality adopted to stage the disease. [18F]F-choline PET/CT induced a change of planned therapy in 5/35 patients in group B (14.3%). Moreover, patients investigated with [18F]F-choline PET/CT alone demonstrated longer biochemical recurrence (BCR)-free survival (30.8 months) in comparison to patients of groups A and B (15.5 and 23.5 months, respectively, p = 0.006), probably due to a more accurate selection of primary treatment. Finally, total lesion choline kinase activity (TLCKA) of the primary lesion, calculated by multiplying metabolic tumor volume and mean standardized uptake value (SUVmean), was able to more effectively discriminate patients who had recurrence after therapy compared to those without (p = 0.03). In our real-world experience [18F]F-choline PET/CT as a tool for the initial management of PCa had a relevant impact in terms of therapy selection and was associated with longer BCR-free survival. Moreover, TLCKA of the primary lesion looks a promising parameter for predicting recurrence after curative therapy.

A phase II study of sEphB4-HSA in metastatic castration-resistant prostate cancer.

84 Background: Ephrin receptors and their membrane-localized ligands induce bidirectional signaling and facilitate tumor-stroma interactions. Expression of EphB4 is increased in prostate cancer tissue and cell lines and retained in castration resistant states, and can promote cell migration, invasion, and metastases. Blocking the EphB4-EphrinB2 pathway, which can be accomplished by soluble EphB4 conjugated to human serum albumin (sEphB4-HSA), has efficacy in preclinical models of aggressive prostate cancer. A phase I clinical trial of sEphB4-HSA led to response or stable disease in 56% of patients, with no grade 4 or 5 related adverse events, and combination pembrolizumab sEphB4-HSA led to a 52% response rate in EphrinB2 expressing urothelial cancer. We hypothesized that targeting the EphB4-EphrinB2 pathway may serve as a therapeutic target in the treatment of metastatic castration resistant prostate cancer (mCRPC). Methods: We conducted a single arm, phase II trial in patients with progressive mCRPC and treatment with at least one second generation androgen receptor (AR)-targeted therapy but no more than three prior therapies for mCRPC. On Day 1 of each cycle patients received sEphB4-HSA 1000 mg IV, with cycle length 14 days cycles 1-6 and cycle length 21 days for cycle 7 and beyond. The primary endpoint was confirmed prostate specific antigen (PSA) response rate (confirmed decrease in PSA by &gt; 50%). We employed a Simon two stage Minimax design, requiring two or more responses among the first 15 patients to enroll an additional ten patients. Results: Fourteen eligible patients enrolled in the study. Median age was 73.5 years (range 52-83), patients had a median baseline PSA value of 65.11 ng/mL (range 7.77-2850 ng/mL) and received a median of three prior therapies (range 1-3) for mCRPC. Ten patients received prior taxane for mCRPC or hormone sensitive prostate cancer. The median length of treatment with sEphB4-HSA was 6.5 weeks (range 2-35 weeks). The potentially treatment-related adverse events (AEs) that occurred in more than 25% of patients were hypertension (10 patients) and fatigue (7 patients). Three patients experienced a serious adverse event potentially related to therapy, including one patient with a grade 5 event (cerebral vascular accident) possibly related to study drug. No patient had a confirmed PSA response, and the study was stopped for futility. Thirteen patients had PSA progression ( &gt; 25% increase in PSA), and one patient withdrew due to toxicity prior to having an evaluable PSA response. The median time to PSA progression was 28 days (95% CI 28-64 days), and median time to radiologic progression was 55 days (95% CI 55 days-NR). Of three patients with measurable disease, two had stable disease and one had progressive disease. Conclusions: In patients with mCRPC who progressed on prior second generation AR-targeted therapy, sEphB4-HSA monotherapy had no discernable anti-tumor activity. Clinical trial information: NCT04033432.

Prostate-specific antigen response among Black and non-Black patients with advanced prostate cancer treated with apalutamide in a urology setting.

124 Background: Apalutamide (APA) is approved to treat patients with non-metastatic castration-resistant prostate cancer (nmCRPC) or metastatic castration-sensitive prostate cancer (mCSPC) in the United States (US) but low enrollment of Black patients in clinical trials has led to limited clinical data about APA for this population. This study describes prostate-specific antigen (PSA) responses among Black and non-Black patients with nmCRPC or mCSPC treated with APA in a real-world community urology setting. Methods: Clinical data from 2/2018 to 3/2021 collected at 69 US urology practices were used to evaluate nmCRPC or mCSPC patients who received ≥1 APA prescription fill (index date). Baseline PSA was reported based with the most recent baseline PSA value and PSA doubling time (PSADT) in months (mo) was calculated in patients with at least 2 PSA tests before APA initiation. PSA response defined as the proportion of patients achieving either a reduction of 50% (PSA50) or 90% (PSA90) from baseline and was evaluated in patients with a PSA test result 8 weeks or later after initiating APA. Among patients with a response, the time from the index date to the response was also evaluated. Study results for Black and non-Black cohorts were summarized separately. Results: Data from 289 nmCRPC (19% Black) and 237 mCSPC (19% Black) patients were identified. Median baseline PSA, median baseline PSADT and post-index PSA responses are shown in Table. A PSA50 response was attained by numerically similar proportions of Black and non-Black patients with nmCRPC or mCSPC. A PSA90 response was observed in a numerically higher proportion of Black than non-Black nmCRPC patients. Median time to PSA50 and PSA90 was also similar between groups. Conclusions: This real-world study of nmCRPC and mCSPC patients demonstrates that PSA50 and PSA90 responses are achieved by high proportions of both Black and non-Black patients. Moreover, the PSA50 and PSA90 responses observed in this study are highly consistent with those observed in APA’s Phase 3 registrational trials for nmCRPC (SPARTAN)1 and for mCSPC (TITAN)2.

PD05-08 REAL-WORLD EFFECTIVENESS AND TREATMENT ADHERENCE OF APALUTAMIDE IN NON-METASTATIC CASTRATION-RESISTANT PROSTATE CANCER PATIENTS

You have accessJournal of UrologyProstate Cancer: Advanced (including Drug Therapy) I (PD05)1 Sep 2021PD05-08 REAL-WORLD EFFECTIVENESS AND TREATMENT ADHERENCE OF APALUTAMIDE IN NON-METASTATIC CASTRATION-RESISTANT PROSTATE CANCER PATIENTS Benjamin Lowentritt, Gordon Brown, Kenneth Kernen, Dominic Pilon, Lorie Ellis, Guillaume Germain, Carmine Rossi, Patrick Lefebvre, Paul Sieber, and Neal Shore Benjamin LowentrittBenjamin Lowentritt More articles by this author , Gordon BrownGordon Brown More articles by this author , Kenneth KernenKenneth Kernen More articles by this author , Dominic PilonDominic Pilon More articles by this author , Lorie EllisLorie Ellis More articles by this author , Guillaume GermainGuillaume Germain More articles by this author , Carmine RossiCarmine Rossi More articles by this author , Patrick LefebvrePatrick Lefebvre More articles by this author , Paul SieberPaul Sieber More articles by this author , and Neal ShoreNeal Shore More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001969.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Real-world evidence on apalutamide (APA), recently approved to treat patients with non-metastatic castration-resistant prostate cancer (nmCRPC), is limited in the United States (US). This study describes prostate-specific antigen (PSA) response and treatment adherence among patients with nmCRPC treated with APA, with stratification by Black and non-Black patients. METHODS: Electronic medical records of 63 US urology practices were obtained from PPS analytics and used to conduct this retrospective study of patients with nmCRPC who received APA on or after 02/14/2018 (index date). Included patients had ≥2 APA prescription fills and ≥12 months of prior prostate cancer management (baseline period). Patients were followed from the index date until a switch to another antineoplastic treatment, death, or end of data (10/04/2019). PSA response (≥50% decline from baseline PSA) and APA adherence rates measured by the medication possession ratio (total days of medication supplied relative to the time between the initiation and the end of the last prescription filled), were described for the overall population and also stratified by racial description, specifically Black and non-Black cohorts. RESULTS: Overall, 193 patients with nmCRPC were initiated on APA (33 were Black [17%], 138 were non-Black [72%], and 22 had an unknown racial background [11%]). Most patients (76%) were aged between 71–90 years. The mean baseline PSA level for the overall, Black, and non-Black cohorts, was 7.0, 10.5, and 5.6 ng/mL, respectively (evaluated on 190, 33, and 135 patients). Among patients with ≥3 baseline PSA tests, median baseline PSA doubling time was 8.5, 7.3, and 8.4 months for the overall, Black, and non-Black cohorts, respectively (evaluated on 90, 16, and 70 patients). At 12 months follow-up, PSA response to APA was 86.0%, 93.1%, and 85.9% for the overall, Black, and non-Black cohorts among patients with both pre- and post-index PSA measurements, respectively (evaluated on 178, 29, and 128 patients). During a mean follow-up period of 11.0, 11.6, and 10.7 months, APA adherence was 93.6%, 90.1%, and 94.5% for the overall, Black and non-Black cohorts, respectively. CONCLUSIONS: This real-world study of nmCRPC patients initiated on APA demonstrated good adherence to medication and robust PSA response consistent with the results from a prior published clinical trial.1 Moreover, these responses were observed in both Black and non-Black patients. Source of Funding: Janssen Scientific Affairs, LLC Reference: 1. NEJM 2018; 378: 1408-18. Google Scholar © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e58-e58 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Benjamin Lowentritt More articles by this author Gordon Brown More articles by this author Kenneth Kernen More articles by this author Dominic Pilon More articles by this author Lorie Ellis More articles by this author Guillaume Germain More articles by this author Carmine Rossi More articles by this author Patrick Lefebvre More articles by this author Paul Sieber More articles by this author Neal Shore More articles by this author Expand All Advertisement Loading ...

Abstract CT207: A phase II trial using grape seed extract for prostate cancer patients with non-metastatic PSA progression after local therapy

Abstract Prostate cancer patients (pts) with non-metastatic prostate specific antigen (PSA) progression after local therapy and a long PSA doubling time (PSADT) usually have a period of PSA observation prior to starting on androgen deprivation therapy (ADT). We report results of an investigator-initiated, IRB-approved Phase II clinical trial (CT.gov-NCT03087903) investigating grape seed extract (GSE) in pts with PSA-only recurrence after maximum local therapy for prostate cancer. Pts with baseline PSA ≥ 0.2 ng/mL and rising PSA on 2 separate occasions and no evidence of metastases were eligible. Pts with baseline PSADT &amp;lt; 4 weeks (if absolute PSA &amp;gt; 2 ng/mL) were excluded. Pts were given 150mg of GSE orally twice daily for 12 months. GSE was administered as a formulation Leucoselect Phytosome-Indena S.p.A. (~100% proanthocyanidins, enriched in lower procyanidin oligomers complexed with soy phospholipids, about 1:2.6 w/w), with increased bioavailability. Study endpoints included PSA response (defined as an increase in PSADT by 30%) and change in PSA velocity. PSA was checked at baseline, 6 weeks and 3, 6, 9, and 12 months after starting GSE. Pts were removed from the trial with clinical/radiographic progression or if PSADT was less than 3 months. Pts completed dietary surveys and provided biologic specimens for tissue banking. The association of time and PSA level was assessed using a mixed effect modeling approach with the intention of calculating the doubling time. The natural log of PSA was taken to satisfy the linearity assumption of this method. Notably, pts on observation with a rising PSA after treatment for prostate cancer could be accrued rapidly to clinical trials; 27 pts were screened for this clinical trial at two sites (between January 2018 - August 2018) with 20 pts registered and started on treatment. Median (range) age and baseline PSA of pts enrolled were 71 (60 - 83) and 2.65 (0.44 - 17.44), respectively. Mean pretreatment PSADT was 5.4 months. GSE was well tolerated without serious adverse effects. 8 patients were withdrawn early due to PSADT progression of &amp;lt;3 months. The remaining 12 patients completed 12 months of follow-up. Mean post-treatment PSADT was 6.4 months. 9 patients met the endpoint of a PSADT increase of 30% or more. Taken together these results indicate that 300mg of daily GSE may improve PSA kinetics in pts with a rising PSA after maximum local therapy. This work was supported by NCI P30 CA46934 Cancer Center Support Grant, Cancer League of Colorado, the Writer Foundation, and the Barbara and Richard Gardner Fund for Prostate Cancer Research. Citation Format: Paul Maroni, Elizabeth R. Kessler, Rodrigo Rodrigues-Pessoa, Andrew Nicklawsky, Thomas Flaig, Elaine Lam, Brandon Bernard, James Moore, Kyra Anderson, Dexiang Gao, Komal Raina, Rajesh Agarwal. A phase II trial using grape seed extract for prostate cancer patients with non-metastatic PSA progression after local therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT207.

Efficacy and Safety of 177Lu-labeled Prostate-specific Membrane Antigen Radionuclide Treatment in Patients with Diffuse Bone Marrow Involvement: A Multicenter Retrospective Study

The 177Lu-labeled prostate-specific membrane antigen (LuPSMA) radionuclide therapy for metastatic castration-resistant prostate cancer is under investigation in a phase III trial (VISION: NCT03511664). However, patients with diffuse bone involvement, diagnosed with a “superscan” by bone scintigraphy at baseline, were excluded due to a lack of efficacy and safety data. We therefore aimed to investigate the feasibility of LuPSMA in patients with diffuse bone marrow involvement on baseline PSMA-targeted positron emission tomography. The primary end points were prostate-specific antigen (PSA) response (Prostate Cancer Working Group 3 [PCWG3]), hematologic safety profile (Common Terminology Criteria for Common Adverse Events [CTCAE]), and overall survival. Secondary end points of quality of life (assessed with Brief Pain Inventory-Short Form questionnaires) and radiologic response (Response Evaluation Criteria in Solid Tumors [RECIST]) were assessed. Through retrospective screening of databases, we identified 43 eligible patients across four centers worldwide who received 154 cycles of LuPSMA under clinical trials or compassionate access programs. Median baseline PSA was 1000 (interquartile range 431–2151) ng/ml. PSA decline of at least 50% at 12 wk was achieved in 22 (58%) patients, while median time to pain progression was 8.3 (95% confidence interval [CI] 4.1–12.6) mo. Median overall survival was 11.6 (95% CI 8.8–14.3) mo. Objective response in nodal or visceral disease was reported in seven (39%) of 18 patients with RECIST measurable disease. Grade 3 anemia, thrombocytopenia, and neutropenia occurred in nine (22%), seven (17%), and three (8%) patients, respectively. Grade 4 thrombocytopenia was noticed in three (8%) patients. In conclusion, patients with diffuse bone marrow involvement demonstrated similar LuPSMA efficacy and safety to phase II evidence. Acceptable safety outcomes do not support exclusion of patients with a superscan from future LuPSMA treatment protocols. Patient summaryIn this report, we investigated the feasibility of prostate-specific membrane antigen (PSMA)-directed radionuclide treatment in patients with metastatic castration-resistant prostate cancer and diffuse bone involvement. We found that, despite a high load of bone metastases, PSMA-targeted therapy remains efficacious and safe when compared with the current phase II trial results.

Abstract D084: Overall survival (OS) of African-American (AA) and Caucasian (CAU) men who received sipuleucel-T for metastatic castration-resistant prostate cancer (mCRPC)—final PROCEED analysis

Abstract BACKGROUND: Prostate cancer risk and mortality are higher in AAs versus CAUs. Post-hoc analyses of pooled Phase 3 data (n = 737) suggested substantial OS benefit for AA men receiving sipuleucel-T (n=33) vs placebo (n = 10) (McLeod 2012). Compared with pooled placebo patients (n = 249), number needed to treat for OS benefit at 3 years was 3 for AAs and 8 for all sipuleucel-T-treated patients (n = 488) (Moses 2017). Herein we analyzed PROCEED (NCT01306890), a large real-world registry, in which all patients received sipuleucel-T. Previously presented at ASCO Annual Meeting 2019 (Sartor 2019).METHODS: In PROCEED, 1902 mCRPC patients received 1 or more sipuleucel-T infusions. OS of all AA (n=221) and CAU (n=1649) men were compared. Baseline prostate-specific antigen (PSA), the most important prognostic variable for OS after sipuleucel-T (Schellhammer 2013), substantially differed by race. Thus, OS for a PSA-matched cohort (n=219 AA; n=438 CAU) was compared and univariable/multivariable analyses were performed. Post-sipuleucel-T use of OS-prolonging anticancer interventions was also assessed. RESULTS: After a median follow-up of 46.6 mo, median OS was 35.2 (all sipuleucel-T-treated AAs) and 29.9 mo (all sipuleucel-T-treated CAUs): HR 0.81, 95% CI 0.68–0.97; P=0.03. In the PSA-matched cohort, median OS was 35.3 and 25.8 mo, respectively (HR 0.70, 95% CI 0.57–0.86; p&amp;lt;0.001). Sipuleucel-T-treated AAs with lower baseline PSA had markedly longer median OS vs sipuleucel-T-treated CAUs. Among those with PSA less than or equal to median baseline PSA (29.48 ng/ml), median OS was 54.3 mo (AA) vs. 33.4 (CAUs); HR 0.52, 95% CI 0.37–0.72; p&amp;lt;0.001. Along with other known prognostic factors, AA race was independently associated with prolonged OS on detailed multivariable analyses (HR 0.60, 95% CI 0.48–0.74; p&amp;lt;0.001) and confirmed on sensitivity analyses. Post-sipuleucel-T life-prolonging anti-cancer therapies were balanced between groups. CONCLUSIONS: Sipuleucel-T-treated AAs had significantly improved OS vs sipuleucel-T-treated CAUs. This analysis marks the largest known racial difference in OS in response to any therapy for mCRPC, a finding with implications for both prostate cancer pathophysiology and cancer immunotherapy. REFERENCES: Sartor 2012 (DOI: 10.1200/JCO.2019.37.15_suppl.5035); McLeod 2012 (DOI: 10.1016/j.juro.2012.02.1051); Moses KA et al 2017 (DOI: 10.1016/j.urology.2016.07.045); Schellhammer 2013 (DOI: 10.1016/j.urology.2013.01.061) Citation Format: Oliver Sartor, Andrew J Armstrong, Chiledum Ahaghotu, David G McLeod, Matthew R Cooperberg, David F Penson, Philip W Kantoff, Nicholas J Vogelzang, Arif Hussain, Christopher. M Pieczonka, Neal D Shore, David I Quinn, Elisabeth I Heath, Ronald F Tutrone, Paul F Schellhammer, Matthew Harmon, Nancy N Chang, Stephen J Freedland, Celestia S Higano. Overall survival (OS) of African-American (AA) and Caucasian (CAU) men who received sipuleucel-T for metastatic castration-resistant prostate cancer (mCRPC)—final PROCEED analysis [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D084.