Active surveillance selection and 3-year durability in intermediate-risk prostate cancer following genomic testing.

BACKGROUND: Genomic testing can add risk stratification information to clinicopathological features in prostate cancer, aiding in shared medical decision-making between the clinician and patient regarding whether active surveillance (AS) or definitive treatment (DT) is most appropriate. Here we examined initial AS selection and 3-year AS durability in patients diagnosed with localized intermediate-risk prostate cancer who underwent Prolaris testing before treatment decision-making. METHODS: This retrospective observational cohort study included 3208 patients from 10 study sites who underwent Prolaris testing at diagnosis from September 2015 to December 2018. Prolaris utilizes a combined clinical cell cycle risk score calculated at diagnostic biopsy to stratify patients by the Prolaris AS threshold (below threshold, patient recommended to AS or above threshold, patient recommended to DT). AS selection rates and 3-year AS durability were compared in patients recommended to AS or DT by Prolaris testing. Univariable and multivariable logistic regression models and Cox proportional hazard models were used with molecular and clinical variables as predictors of initial treatment decision and AS durability, respectively. RESULTS: AS selection was ~2 times higher in patients recommended to AS by Prolaris testing than in those recommended to DT (p < 0.0001). Three-year AS durability was ~1.5 times higher in patients recommended to AS by Prolaris testing than in those recommended to DT (p < 0.0001). Prolaris treatment recommendation remained a statistically significant predictor of initial AS selection and AS durability after accounting for CAPRA or Gleason scores. CONCLUSIONS: Prolaris added significant information to clinical risk stratification to aid in treatment decision making. Intermediate-risk prostate cancer patients who were recommended to AS by Prolaris were more likely to initially pursue AS and were more likely to remain on AS at 3 years post-diagnosis than patients recommended to DT.

Deep and Durable Prostate-specific Antigen Response to Darolutamide with Androgen Deprivation Therapy and Docetaxel, and Association with Clinical Outcomes for Patients with High- or Low-volume Metastatic Hormone-sensitive Prostate Cancer: Analyses of the Randomized Phase 3 ARASENS Study.

BACKGROUND AND OBJECTIVE: Addition of darolutamide to androgen deprivation therapy (ADT) and docetaxel significantly improved overall survival (OS) in ARASENS (NCT02799602). Here we report on prostate-specific antigen (PSA) responses and their association with outcomes. METHODS: ARASENS is an international, double-blind, phase 3 study in patients with metastatic hormone-sensitive prostate cancer (mHSPC) randomized to darolutamide 600 mg orally twice daily (n = 651) or placebo (n = 654), both with ADT + docetaxel. The proportion of patients with undetectable PSA (<0.2 ng/ml) and time to PSA progression (≥25% relative and ≥2 ng/ml absolute increase from nadir) were compared between groups in prespecified exploratory analyses. PSA outcomes by disease volume and the association of undetectable PSA with OS and times to castration-resistant prostate cancer (CRPC) and PSA progression were assessed in post hoc analyses. KEY FINDINGS AND LIMITATIONS: The proportion of patients with undetectable PSA at any time was more than doubled with darolutamide versus placebo, at 67% versus 29% in the overall population, 62% versus 26% in the high-volume subgroup, and 84% versus 38% in the low-volume subgroup. Darolutamide delayed time to PSA progression versus placebo, with hazard ratios of 0.26 (95% confidence interval [CI] 0.21-0.31) in the overall population, 0.30 (95% CI 0.24-0.37) in the high-volume subgroup, and 0.093 (95% CI 0.047-0.18) in the low-volume subgroup. Undetectable PSA at 24 wk was associated with longer OS, with a hazard ratio of 0.49 (95% CI 0.37-0.65) in the darolutamide group, as well as longer times to CRPC and PSA progression, with similar findings in the disease volume subgroups. CONCLUSIONS AND CLINICAL IMPLICATIONS: Darolutamide + ADT + docetaxel led to deep and durable PSA responses in patients with high- or low-volume mHSPC. Achievement of undetectable PSA (<0.2 ng/ml) was correlated with better clinical outcomes.

Efficacy and Safety of Radiotherapy Plus Relugolix in Men With Localized or Advanced Prostate Cancer.

Importance: Combination androgen deprivation therapy (ADT) with radiotherapy is commonly used for patients with localized and advanced prostate cancer. Objective: To assess the efficacy and safety of the oral gonadotropin-releasing hormone antagonist relugolix with radiotherapy for treating prostate cancer. Design, Setting, and Participants: This multicenter post hoc analysis of patients with localized and advanced prostate cancer receiving radiotherapy in 2 randomized clinical trials (a phase 2 trial of relugolix vs degarelix, and a subset of the phase 3 HERO trial of relugolix vs leuprolide acetate) included men who were receiving radiotherapy and short-term (24 weeks) ADT (n = 103) from 2014 to 2015 and men receiving radiotherapy and longer-term (48 weeks) ADT (n = 157) from 2017 to 2019. The data were analyzed in November 2022. Interventions: Patients receiving short-term ADT received relugolix, 120 mg, orally once daily (320-mg loading dose) or degarelix, 80 mg, 4-week depot (240-mg loading dose) for 24 weeks with 12 weeks of follow-up. Patients receiving longer-term ADT received relugolix, 120 mg, orally once daily (360-mg loading dose) or leuprolide acetate injections every 12 weeks for 48 weeks, with up to 90 days of follow-up. Main Outcomes and Measures: Castration rate (testosterone level <50 ng/dL [to convert to nmol/L, multiply by 0.0347) at all scheduled visits between weeks 5 and 25 for patients receiving short-term ADT and weeks 5 and 49 for patients receiving longer-term ADT. Results: Of 260 patients (38 Asian [14.6%], 23 Black or African American [8.8%], 21 Hispanic [8.1%], and 188 White [72.3%] individuals), 164 (63.1%) received relugolix. Relugolix achieved castration rates of 95% (95% CI, 87.1%-99.0%) and 97% (95% CI, 90.6%-99.0%) among patients receiving short-term and longer-term ADT, respectively. Twelve weeks post-short-term relugolix, 34 (52%) achieved testosterone levels to baseline or more than 280 ng/dL. Ninety days post longer-term ADT, mean (SD) testosterone levels were 310.5 (122.4) (106.7) ng/dL (relugolix; n = 15) vs 53.0 ng/dL (leuprolide acetate; n = 8) among the subset assessed for testosterone recovery. Castration resistance-free survival was not statistically different between the relugolix and leuprolide acetate cohorts (hazard ratio, 0.97; 95% CI, 0.35-2.72; P = .62). Adverse events grade 3 or greater for short-term or longer-term relugolix (headache, hypertension, and atrial fibrillation) were uncommon (less than 5%). Conclusions and Relevance: The results of these 2 randomized clinical trials suggest that relugolix rapidly achieves sustained castration in patients with localized and advanced prostate cancer receiving radiotherapy. No new safety concerns were identified when relugolix was used with radiotherapy.

Testosterone Recovery for Relugolix Versus Leuprolide in Men with Advanced Prostate Cancer: Results from the Phase 3 HERO Study.

BACKGROUND: In the HERO study, relugolix demonstrated sustained testosterone suppression superior to that of leuprolide acetate (97% vs 89%; difference 7.9% [95% confidence interval, 4.1-12%; p < 0.001]). OBJECTIVE: To analyze testosterone recovery in a prespecified subset of men from the HERO study not indicated to continue androgen deprivation therapy. DESIGN, SETTING, AND PARTICIPANTS: Men (N = 934) were randomized (2:1) to receive relugolix 120 mg orally daily or leuprolide acetate injections every 12 wk for 48 wk. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Testosterone recovery was assessed in 184 men who completed 48 wk of treatment. During the 90-d recovery period, assessments included time to testosterone recovery (>280 ng/dl; ≥80% of baseline testosterone), serum levels of prostate-specific antigen and pituitary hormones, and adverse events. RESULTS AND LIMITATIONS: The cumulative incidence rate of testosterone recovery to >280 ng/dl at 90 d following drug discontinuation was significantly higher in the relugolix cohort (n = 137) than in the leuprolide acetate cohort (n = 47; 54% vs 3.2%; nominal p = 0.002). The median time to testosterone recovery was faster following relugolix treatment than with leuprolide acetate treatment (86.0 d vs 112.0 d). Compared with leuprolide acetate, more men treated with relugolix achieved ≥80% of baseline testosterone levels (39% vs 2.1%). Men ≤65 yr and those with baseline testosterone greater than the median had a higher incident rate of testosterone recovery. Adverse events were generally similar between treatment groups. One limitation is the short testosterone recovery follow-up period. CONCLUSIONS: Oral relugolix had faster and more complete recovery of testosterone to normal levels after treatment discontinuation than leuprolide acetate in a subset of men from the HERO study. The clinical implications of a faster testosterone recovery with relugolix may be significant for men being treated with androgen deprivation therapy and influence treatment decisions. PATIENT SUMMARY: The male hormone testosterone is reduced during androgen deprivation therapy for prostate cancer. Reduced testosterone levels cause side effects, impacting patient quality of life. When treatment is stopped, the side effects lessen over time as the levels of testosterone come back to pretreatment range (testosterone recovery). In this study, we found that the time to testosterone recovery was faster with relugolix than with leuprolide acetate.

Relugolix vs. Leuprolide Effects on Castration Resistance-Free Survival from the Phase 3 HERO Study in Men with Advanced Prostate Cancer.

Background: Relugolix is an oral GnRH receptor antagonist approved for men with advanced prostate cancer. Relugolix treatment has demonstrated an ability to lower testosterone to sustained castration levels in the phase 4 HERO study. Herein, we describe the results of a secondary endpoint of castration resistance-free survival (CRFS) during 48 weeks of treatment and profile patients with castration-resistant prostate cancer (CRPC). Methods: Subjects were 2:1 randomized to either relugolix 120 mg orally once daily (after a single 360 mg loading dose) or 3-monthly injections of leuprolide for 48 weeks. CRFS, defined as the time from the date of first dose to the date of confirmed prostate-specific antigen progression while castrated or death due to any reason was conducted in the metastatic disease population and the overall modified intention-to-treat (mITT) populations. Results: The CRFS analysis (mITT population) included 1074 men (relugolix: n = 717; leuprolide: n = 357) with advanced prostate cancer as well as 434 men (relugolix: n = 290; leuprolide: n = 144) with metastatic prostate cancer. In the metastatic disease populations, CRFS rates were 74.3% (95% CI: 68.6%, 79.2%) and 75.3% (95% CI: 66.7%, 81.9%) in the relugolix and leuprolide groups, respectively (hazard ratio: 1.03 [0.68, 1.57]; p = 0.84) at week 48. Results in the overall mITT population were similar to the metastatic population. No new safety findings were identified. Conclusions: In men with metastatic disease or in the overall population of the HERO study, CRFS assessed during the 48-week treatment with relugolix was not significantly different than standard-of-care leuprolide. Relugolix had similar efficacy for men with/without CRFS progression events.

Improved Outcomes with Enzalutamide in Biochemically Recurrent Prostate Cancer.

BACKGROUND: Patients with prostate cancer who have high-risk biochemical recurrence have an increased risk of progression. The efficacy and safety of enzalutamide plus androgen-deprivation therapy and enzalutamide monotherapy, as compared with androgen-deprivation therapy alone, are unknown. METHODS: In this phase 3 trial, we enrolled patients with prostate cancer who had high-risk biochemical recurrence with a prostate-specific antigen doubling time of 9 months or less. Patients were randomly assigned, in a 1:1:1 ratio, to receive enzalutamide (160 mg) daily plus leuprolide every 12 weeks (combination group), placebo plus leuprolide (leuprolide-alone group), or enzalutamide monotherapy (monotherapy group). The primary end point was metastasis-free survival, as assessed by blinded independent central review, in the combination group as compared with the leuprolide-alone group. A key secondary end point was metastasis-free survival in the monotherapy group as compared with the leuprolide-alone group. Other secondary end points were patient-reported outcomes and safety. RESULTS: A total of 1068 patients underwent randomization: 355 were assigned to the combination group, 358 to the leuprolide-alone group, and 355 to the monotherapy group. The patients were followed for a median of 60.7 months. At 5 years, metastasis-free survival was 87.3% (95% confidence interval [CI], 83.0 to 90.6) in the combination group, 71.4% (95% CI, 65.7 to 76.3) in the leuprolide-alone group, and 80.0% (95% CI, 75.0 to 84.1) in the monotherapy group. With respect to metastasis-free survival, enzalutamide plus leuprolide was superior to leuprolide alone (hazard ratio for metastasis or death, 0.42; 95% CI, 0.30 to 0.61; P<0.001); enzalutamide monotherapy was also superior to leuprolide alone (hazard ratio for metastasis or death, 0.63; 95% CI, 0.46 to 0.87; P = 0.005). No new safety signals were observed, with no substantial between-group differences in quality-of-life measures. CONCLUSIONS: In patients with prostate cancer with high-risk biochemical recurrence, enzalutamide plus leuprolide was superior to leuprolide alone with respect to metastasis-free survival; enzalutamide monotherapy was also superior to leuprolide alone. The safety profile of enzalutamide was consistent with that shown in previous clinical studies, with no apparent detrimental effect on quality of life. (Funded by Pfizer and Astellas Pharma; EMBARK ClinicalTrials.gov number, NCT02319837.).

Impact of Concomitant Cardiovascular Therapies on Efficacy and Safety of Relugolix vs Leuprolide: Subgroup Analysis from HERO Study in Advanced Prostate Cancer.

INTRODUCTION: Cardiovascular (CV) events are the leading cause of death in prostate cancer. Men with prostate cancer are likely to have CV risk factors and use CV-related concomitant medications. In the phase 3 HERO study, a 54% lower incidence of major adverse cardiac events was reported in men treated with the oral gonadotropin-releasing hormone (GnRH) receptor antagonist, relugolix, vs leuprolide. Herein, we characterize the impact of concomitant CV therapies on efficacy and safety in the HERO study. METHODS: In HERO, 930 men with advanced prostate cancer (APC) were randomized 2:1 and treated with relugolix (120 mg orally once daily; after single 360 mg loading dose) or leuprolide (injections every 3 months) for 48 weeks. Subgroups analyzed included men who received antihypertensives, antithrombotics, or lipid-modifying therapies (LMAs), as well as the most common drug classes (> 10%) and single most common agent within each class. Assessments included sustained testosterone suppression to castrate levels (< 50 ng/dL) through 48 weeks and safety. RESULTS: Antihypertensives, antithrombotics, and LMAs were utilized by 52.7%, 39.1%, and 39.6% of men in HERO, respectively. In the main subgroups, point estimates for sustained castration rates were generally consistent with overall estimates of relugolix and leuprolide observed in the overall population. Sustained castration rates were also mostly consistent for men taking the most common drug classes and individual agents in each class (losartan [n = 103]: relugolix, 95.4% vs leuprolide, 80.6%; amlodipine [n = 229]: 97.2% vs 85.5%; metoprolol [n = 88]: 95.7% vs 86.9%; acetylsalicylic acid [n = 259]: 97.0% vs 92.1%; clopidogrel [n = 43]: 96.4% vs 86.7%; simvastatin [n = 78]: 98.0% vs 87.3%). Incidence and types of adverse events (AEs) among men who received these medications were mostly consistent with overall population results, with some increases in grade ≥ 3 and fatal AEs. CONCLUSION: Relugolix suppressed testosterone and was generally well tolerated when given with concomitant CV agents. TRIAL REGISTRATION: Clinical Trial ID NCT03085095. PRIOR PRESENTATION: Data presented at 15th Annual Genitourinary Cancers Symposium; February 17-19, 2022, San Francisco, CA, USA [Abstract 101, Poster board E11]. The published abstract from this presentation can be found at https://ascopubs.org/doi/10.1200/JCO.2022.40.6_suppl.101 .

ExoDx prostate test as a predictor of outcomes of high-grade prostate cancer - an interim analysis.

BACKGROUND: Patient outcomes were assessed based on a pre-biopsy ExoDx Prostate (EPI) score at 2.5 years of the 5-year follow-up of ongoing prostate biopsy Decision Impact Trial of the ExoDx Prostate (IntelliScore). METHODS: Prospective, blinded, randomized, multisite clinical utility study was conducted from June 2017 to May 2018 (NCT03235687). Urine samples were collected from 1049 men (≥50 years old) with a PSA 2-10 ng/mL being considered for a prostate biopsy. Patients were randomized to EPI vs. standard of care (SOC). All had an EPI test, but only EPI arm received results during biopsy decision process. Clinical outcomes, time to biopsy and pathology were assessed among low (<15.6) or high (≥15.6) EPI scores. RESULTS: At 2.5 years, 833 patients had follow-up data. In the EPI arm, biopsy rates remained lower for low-risk EPI scores than high-risk EPI scores (44.6% vs 79.0%, p < 0.001), whereas biopsy rates were identical in SOC arm regardless of EPI score (59.6% vs 58.8%, p = 0.99). Also in the EPI arm, the average time from EPI testing to first biopsy was longer for low-risk EPI scores compared to high-risk EPI scores (216 vs. 69 days; p < 0.001). Similarly, the time to first biopsy was longer with EPI low-risk scores in EPI arm compared to EPI low-risk scores in SOC arm (216 vs 80 days; p < 0.001). At 2.5 years, patients with low-risk EPI scores from both arms had less HGPC than high-risk EPI score patients (7.9% vs 26.8%, p < 0.001) and the EPI arm found 21.8% more HGPC than the SOC arm. CONCLUSIONS: This follow-up analysis captures subsequent biopsy outcomes and demonstrates that men receiving EPI low-risk scores (<15.6) significantly defer the time to first biopsy and remain at a very low pathologic risk by 2.5-years after the initial study. The EPI test risk stratification identified low-risk patients that were not found with the SOC.

Impact of Concomitant Prostate Cancer Medications on Efficacy and Safety of Relugolix Versus Leuprolide in Men With Advanced Prostate Cancer.

BACKGROUND: To characterize the impact of concomitant prostate cancer treatments with the use of relugolix, the oral GnRH receptor antagonist, in advanced prostate cancer, a subgroup and pharmacokinetic/pharmacodynamic analyses of the HERO study was undertaken. PATIENTS AND METHODS: Overall, 934 patients were randomized 2:1 to receive relugolix 120 mg orally once daily or leuprolide injections every 12 weeks for 48 weeks. In the setting of rising PSA, patients could receive enzalutamide or docetaxel 2 months after study initiation. Assessments included sustained testosterone suppression to castrate levels (<50 ng/dL) through 48 weeks and safety parameters. Subgroups analyzed included patients with or without concomitant enzalutamide or docetaxel. A sensitivity analysis of the primary endpoint was performed excluding patients who received concomitant therapies that may affect testosterone. Pharmacokinetic/pharmacodynamic analyses of 20 participants in the relugolix treatment group assessed the net effect of enzalutamide on exposure to relugolix. RESULTS: Overall, 125 patients (13.4%) took concomitant therapies that could impact testosterone levels. Enzalutamide (n = 23) was the most frequently used therapy in the relugolix (2.7%) and leuprolide groups (1.9%). Docetaxel (n = 13) was used by 1.3% and 1.6% of patients in the relugolix and leuprolide groups, respectively. All other relevant concomitant therapy were used in <1% of population. Sensitivity analysis showed concomitant therapy did not impact the testosterone levels. Castration rates were similar with and without concomitant use of enzalutamide or docetaxel. No clinically relevant differences in adverse events were observed between subgroups in either treatment group. No differences in relugolix Ctrough or testosterone concentrations were observed, suggesting that any induction or inhibition properties of enzalutamide on relugolix metabolism result in a neutral net effect on relugolix exposure and testosterone suppression. CONCLUSION: Treatment with relugolix was associated with similar efficacy and safety profiles with and without concomitant enzalutamide or docetaxel. Standard-of-care use of relugolix in combination with these agents is supported by these data.

A Phase I Clinical Trial Evaluating the Safety and Dosing of Relugolix with Novel Hormonal Therapy for the Treatment of Advanced Prostate Cancer.

BACKGROUND: Androgen deprivation therapy (ADT), a cornerstone of prostate cancer treatment, is commonly co-prescribed as combination therapy. OBJECTIVE: To better understand the safety and tolerability profile of relugolix, an oral non-peptide gonadotropin-releasing hormone (GnRH) receptor antagonist, in combination with abiraterone acetate (abiraterone) and apalutamide, a phase I study was undertaken. PATIENTS AND METHODS: This is an ongoing, 52-week, open-label, parallel cohort study of relugolix in combination with abiraterone in men with metastatic castration-sensitive prostate cancer (mCSPC) or metastatic castration-resistant prostate cancer (mCRPC) [Part 1] and apalutamide in men with mCSPC or non-metastatic castration-resistant prostate cancer (nmCRPC) [Part 2]. Eligible patients treated with leuprolide acetate or degarelix with abiraterone or apalutamide prior to baseline, at which time they were transitioned to relugolix. Assessments included reporting of adverse events, clinical laboratory tests, vital sign measurements, electrocardiogram (ECG) parameters, and testosterone serum concentrations. In this interim report, patients completing ≥12 weeks were included. RESULTS: Overall, 15 men were enrolled in Part 1 and 10 in Part 2. Adverse events were mostly mild-to-moderate in intensity and were consistent with the known safety profiles of the individual medications. No transition (from prior ADT treatment)- or time-related trends in clinical laboratory tests, vital sign measurements, or ECG parameters were observed. Mean testosterone concentrations remained below castration levels. CONCLUSIONS: Combination therapy of relugolix and abiraterone or apalutamide was associated with a favorable safety and tolerability profile consistent with the known profiles of the individual medications. Castration levels of testosterone were maintained after transitioning to relugolix from other ADTs. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04666129.

Niraparib with Abiraterone Acetate and Prednisone for Metastatic Castration-Resistant Prostate Cancer: Phase II QUEST Study Results.

Niraparib (NIRA) is a highly selective inhibitor of poly (adenosine diphosphate-ribose) polymerase, PARP1 and PARP2, which play a role in DNA repair. The phase II QUEST study evaluated NIRA combinations in patients with metastatic castration-resistant prostate cancer who were positive for homologous recombination repair gene alterations and had progressed on 1 prior line of novel androgen receptor-targeted therapy. Results from the combination of NIRA with abiraterone acetate plus prednisone, which disrupts androgen axis signaling through inhibition of CYP17, showed promising efficacy and a manageable safety profile in this patient population.

Transurethral Vapor Ablation in Patients with Intermediate-Risk Localized Prostate Cancer.

Purpose: We report results of a prospective, multicenter single-arm study of transurethral vapor ablation (TUVA) of prostate tissue in patients with unilateral, intermediate-risk, localized prostate cancer (PCa). Materials and Methods: Men ≥45 years of age with biopsy-confirmed unilateral Gleason grade group 2 (GGG2) adenocarcinoma of the prostate, prostate volume of 20-80 cc, and prostate-specific antigen (PSA) ≤15 ng/mL were enrolled. Cystoscopy and transrectal ultrasound (TRUS) guidance were used to deliver ∼103°C water vapor to prostate zones for unilateral hemigland ablation, including destruction of cancers detected by multiparametric MRI (mpMRI) and confirmed by biopsy. The primary outcomes were device-related serious adverse events (SAEs). At 7 days and 6 months postprocedure, the ablation extent was assessed by mpMRI; MRI/TRUS fusion biopsies were completed at 6 months. Quality of life (QOL) was assessed with validated questionnaires. Results: All subjects underwent a single hemigland TUVA procedure. No SAEs occurred. Grade 2 procedure-related AEs included transient urinary retention (n = 4) and erectile (n = 1) or ejaculatory dysfunction (n = 1). At 7 days, mpMRI revealed complete ablation of 14/17 (82%) visible lesions. At 6 months, biopsies showed no Gleason pattern ≥4 or ≥GGG2 cancer on the treated side of prostates in 13/15 (87%) subjects. Ten of 15 (67%) subjects were biopsy negative. Of the 5 biopsy-negative subjects, 2 had one core each of 3 + 4 disease and 3 had one core each of 3 + 3 disease with ≤5% involvement. Median prostate volume was reduced by 40.7% and PSA by 58%. Extensive QOL assessments showed, on average, no appreciable negative effects of treatment. Conclusions: Initial evidence suggests that TUVA is safe in men with intermediate-risk PCa. Preliminary results demonstrate the absence of ≥GGG2 disease on the treated side in 87% of men and a favorable QOL profile.

Enzalutamide and Quality of Life in Biochemically Recurrent Prostate Cancer.

BACKGROUND: EMBARK, a controlled trial reported elsewhere, showed enzalutamide plus leuprolide (combination) and enzalutamide monotherapy prolonged metastasis-free survival versus placebo plus leuprolide (alone) in patients with high-risk biochemically recurrent prostate cancer. Health-related quality of life was also analyzed but not reported. METHODS: In EMBARK, patients with biochemical recurrence (prostate-specific antigen doubling time of ≤9 months) were randomly assigned (1:1:1) to combination (n=355), leuprolide-alone (n=358), or enzalutamide monotherapy (n=355). In this article we provide the patient-reported outcomes (PROs) from EMBARK at baseline and every 12 weeks until metastasis or death. The key end point was time to first and confirmed clinically meaningful deterioration (TTFD/TTCD) in pain and health-related quality of life using four PRO measures and predefined thresholds. RESULTS: At baseline, all groups had high health-related quality of life. For worst pain, the median TTFD was 19.35 months with leuprolide alone, 13.93 months with combination (hazard ratio, 1.08; 95% confidence interval [CI], 0.89 to 1.30) and 16.59 months with monotherapy (hazard ratio, 1.09; 95% CI, 0.90 to 1.31). The median TTCD was 66.27 months with leuprolide alone, 80.00 months with combination (hazard ratio, 0.82; 95% CI, 0.65 to 1.04), and 60.91 months with monotherapy (hazard ratio, 1.02; 95% CI, 0.82 to 1.28). For Functional Assessment of Cancer Therapy­Prostate total score, the median TTFD was 11.10 months with leuprolide alone, 8.31 months with combination (hazard ratio, 1.14; 95% CI, 0.95 to 1.36), and 8.38 months with monotherapy (hazard ratio, 1.17; 95% CI, 0.98 to 1.39). The median TTCD was 36.53 months with leuprolide alone, 38.77 months with combination (hazard ratio, 1.04; 95% CI, 0.85 to 1.28), and 30.55 months with monotherapy (hazard ratio, 1.16; 95% CI, 0.95 to 1.41). CONCLUSIONS: The PROs from EMBARK show that both enzalutamide combination and monotherapy versus leuprolide alone, with oncologic benefits noted above, preserved high health-related quality of life in patients with high-risk biochemical recurrence of prostate cancer. (Funded by Pfizer and Astellas Pharma; ClinicalTrials.gov number, NCT02319837.)

ADXS31142 Immunotherapy ± Pembrolizumab Treatment for Metastatic Castration-Resistant Prostate Cancer: Open-Label Phase I/II KEYNOTE-046 Study.

BACKGROUND: ADXS31-142 is an attenuated Listeria monocytogenes-based immunotherapy targeting prostate-specific antigen (PSA), being evaluated as monotherapy and combined with pembrolizumab for metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: The 2-part phase I/II KEYNOTE-046 study enrolled men with mCRPC who have progressed after 2 or fewer prior systemic treatment regimens in the metastatic setting. In Part A, intravenous ADXS31-142 monotherapy was given every 3 weeks (q3w) to 3 dose-escalation cohorts. In Part B, ADXS31-142 (1 × 109 colony-forming units) plus pembrolizumab (200 mg) was administered intravenously q3w for 3 doses with a fourth pembrolizumab dose 3 weeks later (12-week cycles) for up to 24 months or until progression/toxicity. Endpoints included safety, overall response rate, progression-free survival (PFS), overall survival (OS), and immunogenicity. RESULTS: Fifty patients received ADXS31-142 alone (n = 13) or with pembrolizumab (n = 37). Among the 37 RECIST-evaluable patients (n = 8 Part A; n = 29 Part B), there were no objective responses. Median PFS was 2.2 months (95% CI: 0.8-7.4) with monotherapy and 5.4 months (95% CI: 2.3-7.9) with the combination; median OS was 7.8 months (95% CI: 4.4-18.5) and 33.7 months (95% CI: 15.4-not evaluable), respectively. Promising OS benefit was observed in combination-treated patients who had received prior docetaxel (16.0 months, 95% CI: 6.4-34.6; n = 20) and those with visceral metastasis (16.4 months, 95% CI 4.0-not evaluable; n = 11). All patients had ≥1 treatment-related adverse event, mostly grade 1/2 manageable events. No additive toxicity was observed with combination treatment. CONCLUSIONS: Combining ADXS31-142 with pembrolizumab was safe and well tolerated. The observed OS in mCRPC warrants further testing of this combination. CLINICAL TRIAL REGISTRATION: NCT02325557.

A Phase Ib/II Study of Sabizabulin, a Novel Oral Cytoskeleton Disruptor, in Men with Metastatic Castration-resistant Prostate Cancer with Progression on an Androgen Receptor-targeting Agent.

PURPOSE: Sabizabulin, an oral cytoskeleton disruptor, was tested in a phase Ib/II clinical study in men with metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: The phase Ib portion utilized a 3+3 design with escalating daily oral doses of 4.5-81 mg and increasing schedule in 39 patients with mCRPC treated with one or more androgen receptor-targeting agents. Prior taxane chemotherapy was allowed. The phase II portion tested a daily dose of 63 mg in 41 patients with no prior chemotherapy. Efficacy was assessed using PCWG3 and RECIST 1.1 criteria. RESULTS: The MTD was not defined in the phase Ib and the recommended phase II dose was set at 63 mg/day. The most common adverse events (>10% frequency) at the 63 mg oral daily dosing (combined phase Ib/II data) were predominantly grade 1-2 events. Grade ≥3 events included diarrhea (7.4%), fatigue (5.6%), and alanine aminotransferase/aspartate aminotransferase elevations (5.6% and 3.7%, respectively). Neurotoxicity and neutropenia were not observed. Preliminary efficacy data in patients treated with ≥1 continuous cycle of 63 mg or higher included objective response rate in 6 of 29 (20.7%) patients with measurable disease (1 complete, 5 partial) and 14 of 48 (29.2%) patients had PSA declines. The Kaplan-Meier median radiographic progression-free survival was estimated to be 11.4 months (n = 55). Durable responses lasting >2.75 years were observed. CONCLUSIONS: This clinical trial demonstrated that chronic oral daily dosing of sabizabulin has a favorable safety profile with preliminary antitumor activity. These data support the ongoing phase III VERACITY trial of sabizabulin in men with mCRPC.

Validation of a CE-IVD, urine exosomal RNA expression assay for risk assessment of prostate cancer prior to biopsy.

Improved risk stratification of patients suspected of prostate cancer prior to biopsy continues to be an unmet clinical need. ExoDx Prostate (IntelliScore) "EPI" is a non-invasive urine test utilizing RNA from exosomes to provide a risk score that correlates with the likelihood of finding high grade prostate cancer at biopsy. Here, we present the results from a prospective clinical validation study of EPI-CE, a CE-marked in-vitro diagnostic (IVD) assay, specifically developed for use in European clinical laboratories. The study (NCT04720599) enrolled patients with ≥ 50 years, PSA 2-10 ng/mL, prior to MRI, who were scheduled for initial biopsy. First catch urine samples were collected from participants without prior digital rectal examination or prostate massage. Exosomal RNA was isolated and expression levels of three biomarkers ERG, PCA3 and SPDEF were analyzed according to the EPI-CE Instructions For Use. In the study cohort of N = 109 patients, EPI-CE was validated to have a Negative Predictive Value of 89%, a Sensitivity of 92% and a superior performance to two commonly used multiparametric risk calculators (PCPT and ERSPC) in both Receiver Operating Characteristics with a higher Area Under the Curve for EPI-CE 0.67 (95% CI 0.56-0.77) versus PCPT 0.59 (95% CI 0.47-0.71) and ERSPC 0.60 (95% CI 0.49-0.72) and higher Net Benefits analysis across a wide range of risk acceptance levels. This is the first clinical study reporting on the performance of EPI-CE. We demonstrate that EPI-CE provides information beyond standard clinical parameters and provides a better risk assessment prior to MRI, of patients suspected of prostate cancer, than the commonly used multiparametric risk calculators.

Pre-diagnosis urine exosomal RNA (ExoDx EPI score) is associated with post-prostatectomy pathology outcome.

PURPOSE: ExoDx Prostate IntelliScore (EPI) is a non-invasive urine exosome RNA-based test for risk assessment of high-grade prostate cancer. We evaluated the association of pre-biopsy test results with post-radical prostatectomy (RP) outcomes to understand the potential utility of EPI to inform invasive treatment vs active surveillance (AS) decisions. METHODS: Urine samples were collected from 2066 men scheduled for initial biopsy with PSA between 2 and 10 ng/mL, no history of prostate cancer, and ≥ 50 years across multiple clinical studies. 310 men proceeded to RP, of which 111 patients had Gleason group grade 1 (GG1) at biopsy and would have been potential candidates for AS. We compared pre-biopsy urine scores with ERSPC and PCPT multivariate risk calculator scores for men with GG1 at biopsy to post-RP pathology. RESULTS: Urine EPI scores were significantly lower in men with GG1 at biopsy than in men with > GG1 (p = 0.04), while there were no differences in multivariate risk scores used in standard clinical practice (p > 0.05). Further, EPI scores were significantly lower in men with GG1 at biopsy who remained GG1 post-RP compared to men upgraded to ≥ GG3 post-RP (p < 0.001). In contrast, none of the multiparametric risk calculators showed significant differences (p > 0.05). Men with GG1 at biopsy and EPI score < 15.6 had zero rate of upgrading to ≥ GG3 post-RP compared to 16.0% for EPI scores ≥ 15.6. CONCLUSIONS: The EPI urine biomarker outperformed the multivariate risk calculators in a homogenous risk group of pre-biopsy men. The EPI score was associated with low-risk pathology post-RP, with potential implications on informing AS decisions. TRIAL REGISTRATION: NCT02702856, NCT03031418, NCT03235687, NCT04720599.

Predicting high-grade prostate cancer at initial biopsy: clinical performance of the ExoDx (EPI) Prostate Intelliscore test in three independent prospective studies.

BACKGROUND: The ability to discriminate indolent from clinically significant prostate cancer (PC) at the initial biopsy remains a challenge. The ExoDx Prostate (IntelliScore) (EPI) test is a noninvasive liquid biopsy that quantifies three RNA targets in urine exosomes. The EPI test stratifies patients for risk of high-grade prostate cancer (HGPC; ≥ Grade Group 2 [GG] PC) in men ≥ 50 years with equivocal prostate-specific antigen (PSA) (2-10 ng/mL). Here, we present a pooled meta-analysis from three independent prospective-validation studies in men presenting for initial biopsy decision. METHODS: Pooled data from two prospective multi-site validation studies and the control arm of a clinical utility study were analyzed. Performance was evaluated using the area under the receiver-operating characteristic curve (AUC), negative predictive value (NPV), positive predictive value (PPV), sensitivity, and specificity for discriminating ≥ GG2 from GG1 and benign pathology. RESULTS: The combined cohort (n = 1212) of initial-biopsy subjects had a median age of 63 years and median PSA of 5.2 ng/mL. The EPI AUC (0.70) was superior to PSA (0.56), Prostate Cancer Prevention Trial Risk Calculator (PCPT-RC) (0.62), and The European Randomized Study of Screening for Prostate Cancer (ERSPC) (0.59), (all p-values <0.001) for discriminating GG2 from GG1 and benign histology. The validated cutoff of 15.6 would avoid 23% of all prostate biopsies and 30% of "unnecessary" (benign or Gleason 6/GG1) biopsies, with an NPV of 90%. CONCLUSIONS: EPI is a noninvasive, easy-to-use, urine exosome-RNA assay that has been validated across 3 independent prospective multicenter clinical trials with 1212 subjects. The test can discriminate high-grade (≥GG2) from low-grade (GG1) cancer and benign disease. EPI effectively guides the biopsy-decision process independent of PSA and other standard-of-care factors.