Background and Update for ECOG-ACRIN EA8212: A Randomized Phase 3 Trial of Intravesical Bacillus Calmette-Guérin (BCG) Versus Intravesical Docetaxel and Gemcitabine Treatment in BCG-naïve High-grade Non-muscle-invasive Bladder Cancer (BRIDGE)

EA8212 BRIDGE is a phase 3 randomized trial comparing BCG vs GemDoce for BCG naïve high-risk non-muscle-invasive bladder cancer. This article provides an explanation for the rationale of the clinical trial and details the study design.

Phase III study of local or systemic therapy intensification directed by PET in prostate cancer patients with post-prostatectomy biochemical recurrence (INDICATE): ECOG-ACRIN EA8191

TPS402

Background: Salvage radiation therapy (sRT) to the prostate bed and pelvic nodes with short-term androgen deprivation therapy (STAD) is considered a standard of care (SOC) salvage therapy (ST) paradigm for prostate cancer (PC) patients (pts) with post-prostatectomy (RP) biochemical recurrence (BCR). PET imaging with recently FDA-approved agents in this setting (18F-Fluciclovine, 18F-DCFPyL and 68Ga-PSMA-11), have shown improved accuracy for detection of metastases not identified with conventional imaging (CIM). Given the greater sensitivity and specificity of PET, its findings are being increasingly but variably applied to justify modification or omission of SOC therapies without high-level evidence of clinical benefit. PET may help identify candidates for different treatment intensification approaches. In metastatic prostate cancer, metastasis-directed RT (MDT) has been used to avoid or delay systemic therapy in men with oligometastatic disease. Apalutamide (Apa) is an androgen receptor signaling inhibitor that has been shown to improve outcomes when added to ADT in mCSPC. This study will evaluate whether patients with PET-detected lesions outside the pelvis will benefit from addition of MDT to treatment intensification with STAD/Apa, and whether patients with no PET-detected lesions outside the pelvis will benefit from addition of Apa to standard sRT/STAD. Methods: PC pts with post-RP BCR (PSA>0.5ng/mL; >0.2ng/mL if first detectable within 12 mos of RP) and no extrapelvic metastases on CIM who are candidates for SOC ST (sRT to prostate bed and pelvic nodes with STAD) are eligible. Pts will undergo SOC baseline PET using a FDA-approved tracer. Based on institutional clinical interpretation of the SOC PET, pts will be placed in Cohort 1 (PET-negative) or 2 (PET-positive for extra-pelvic metastases). Cohort 1 will be randomized to SOC ST +/- Apa for 6 months and Cohort 2 will be randomized to SOC ST and Apa +/- MDT to PET-positive lesions. The primary endpoint is PFS, defined as time from randomization to radiographic progression on CIM, symptomatic disease or death, whichever occurs first. Primary objectives are to evaluate whether addition of Apa to SOC ST and addition of MDT to SOC ST and Apa could prolong PFS in Cohorts 1 and 2, respectively. For Cohort 1, 480 pts will be randomized with 85% power to distinguish a 5-year PFS rate of 90% (Apa arm) vs. 80% (SOC arm) using one-sided stratified logrank test with type I error of 0.025. For Cohort 2, 324 pts will be randomized with 85% power to distinguish a 5-year PFS rate of 76.5% in the experimental arm from 61.5% in the control arm. Secondary endpoints include overall and event-free survival, toxicity, PET progression and quality of life. Clinical trial information: NCT04423211 .

Baseline characteristics associated with PSA progression-free survival in patients (pts) with high-risk biochemically relapsed prostate cancer: Results from the phase 3 PRESTO study (AFT-19)

208

Background: In the Phase 3 PRESTO study, intensified androgen deprivation therapy (ADT) with apalutamide (APA) with or without abiraterone acetate plus prednisone (AAP), administered for a finite treatment period of 52 weeks, prolonged prostate-specific antigen progression-free survival (PSA PFS) in pts with high-risk biochemically relapsed prostate cancer (BRPC). We evaluated baseline factors associated with PSA PFS in this study. Methods: PRESTO is a randomized phase 3, open-label trial in pts with BRPC following radical prostatectomy (RP) and PSA doubling time (PSADT) ≤ 9 months (mo), without distant metastases on conventional imaging (NCT03009981). Pts were randomized 1:1:1 to receive a finite 52-week treatment course with ADT, ADT + APA, or ADT + APA + AAP, stratified by PSADT (< 3 vs 3–9 mo), with post-treatment follow-up. Baseline factors associated with PSA PFS including Gleason sum at RP (6-7, 8, ≥ 9) were analyzed in a post hoc fashion. Results: 504 pts were randomized to ADT alone (N = 167), ADT + APA (N = 168) or ADT + APA + AAP (N = 169). Baseline patient characteristics including Gleason sum at diagnosis, serum PSA and PSADT at study entry, time interval from radical prostatectomy, and receipt of prior radiation (none, adjuvant, salvage) were well balanced across the three treatment arms. At the first planned interim analysis, both experimental arms significantly prolonged PSA PFS compared to the control arm (median 24.9 mo for ADT + APA vs 20.3 mo for ADT, HR = 0.52 (95% CI: 0.35–0.77); median 26.0 mo for ADT + APA + AAP vs 20.0 mo for ADT, HR = 0.48 (95% CI: 0.32–0.71)). Across the study cohort, Gleason sum ≥ 9 at diagnosis was associated with shorter PSA PFS (median 21.9 mo for Gleason ≥ 9 vs. 31.1 mo for Gleason 8 vs. 25.2 mo for Gleason 6-7, log-rank p-value = 0.0409). In addition, within each treatment arm, a shorter observed median PSA PFS was detected for patients with Gleason ≥ 9 prostate cancer. Serum PSA and PSADT at study entry, time from prior radical prostatectomy, and prior radiation were not associated with PSA PFS in the overall study cohort or in individual study arms. Conclusions: Gleason sum ≥ 9 prostate cancer at diagnosis was associated with shorter time to PSA progression following subsequent intensified ADT administered for a finite treatment interval in BRPC. Follow-up is ongoing to integrate genomic profiling of primary prostate cancer tissue with these results and validate with longer term endpoints including metastasis-free survival. Clinical trial information: NCT03009981 .

A phase III double blinded study of early intervention after radical prostatectomy with androgen deprivation therapy with darolutamide versus placebo in men at highest risk of prostate cancer metastasis by genomic stratification (ERADICATE)

TPS5114

Background: Patients with high-risk scores by Decipher molecular testing after prostatectomy have a 5-year metastasis rate of 28% (Decipher 0.6-0.7) and 38% (Decipher > 0.7), likely due to micrometastatic disease. Clinical trials with intensified systemic treatment are warranted to increase cure rates and address this unmet need. Previous studies of adjuvant androgen deprivation therapy (ADT) in clinically identified high-risk disease have not demonstrated substantial benefit other than in men with lymph node positive disease. Darolutamide is a novel androgen receptor antagonist with demonstrated efficacy in improving metastasis-free survival (MFS) and overall survival (OS) in patients with non-metastatic castration-resistant prostate cancer, and OS in patients with metastatic hormone-sensitive prostate cancer (mHSPC). Whether treatment with ADT and darolutamide can increase MFS versus ADT plus placebo in the adjuvant setting for men with molecularly identified high-risk prostate cancer is unknown. Methods: Patients with CAPRA-S scores ≥3 and a PSA < 0.2 after radical prostatectomy undergo Decipher testing provided by the trial. Eligible patients with high-risk Decipher scores (> 0.6) will be randomized to treatment with ADT with darolutamide or placebo for 12 months. Patients are stratified by intent to deliver adjuvant radiation and by baseline PSA (undetectable vs detectable but < 0.2 ng/mL). The primary endpoint is MFS defined by novel PET or conventional imaging. With a sample size of 810 patients, the trial has 80% power with one-sided alpha = 0.025 to detect a HR of 0.60 for the experimental arm vs control arm for the primary endpoint. Secondary endpoints include recurrence-free survival, event-free survival, and quality of life (FACT-P, FACT-Cog, and FACIT-Fatigue), overall survival, and other disease-related outcomes. Trial was activated on December 9, 2020, and is currently enrolling patients. Clinical trial information: NCT04484818.

Eight-year survival rates by baseline prognostic groups in patients with metastatic hormone-sensitive prostate cancer (mHSPC): An analysis from the ECOG-ACRIN 3805 (CHAARTED) trial

5081

Background: To date there is no prospective survival data beyond 5 years for patients treated with ADT with or without docetaxel (D) when analyzed by well-defined baseline prognostic risk groups and treatment arms. In this updated analysis of the CHAARTED trial, we report the 8-year survival rate based on disease volume and metachronous vs. de novo metastatic disease status with ADT without or with docetaxel. Methods: An updated survival sweep was conducted in February 2022. Patients were prospectively identified by the state of metastatic disease as metachronous (prior local therapy) vs. de novo and low volume (LV) vs. high volume (HV; visceral and/or ≥4 bone metastases with one lesion beyond the vertebral bodies or pelvis) disease. Overall survival (OS) was defined as time from randomization to death or date last known alive and calculated using the Kaplan-Meier method. Results: Of the 790 patients randomized (last patient enrolled December 2012), 238 patients were still alive with a median follow up of 9.7 years for patients still alive. Median OS in the overall population was 60.4 and 47.2 mos in the ADT+ D and ADT arms respectively (Table; HR: 0.77; 95% CI: 0.65, 0.92; p=0.004). ADT+ D was associated with significantly higher 8-yr OS rate (28.5%) compared to ADT arm (15.4%; HR: 0.67; 95% CI: 0.53, 0.84; p=0.0005) in the de novo HV group (n=421). Notably, the 8-yr OS rates were almost doubled for patients with HV disease with early docetaxel (16% vs.30.2%, p<.0001) and this was seen in patients with both de novo and metachronous HV mHSPC. Conclusions: In this long-term updated analysis, ADT+D continued to demonstrate significantly improved OS in the overall population and this is still most clearly evident in patients with de novo HV mHSPC. Our findings highlight the role of baseline prognostic risk groups in predicting longer term survival and benefits from treatment intensification. Clinical trial information: NCT00309985. [Table: see text]

Randomized Phase 2 Trial of Abiraterone Acetate Plus Prednisone, Degarelix, or the Combination in Men with Biochemically Recurrent Prostate Cancer After Radical Prostatectomy

Background

Phase 2 trial endpoints that can be utilized in high-risk biochemical recurrence (BCR) after prostatectomy as a way of more rapidly identifying treatments for phase 3 trials are urgently needed. The efficacy of abiraterone acetate plus prednisone (AAP) in BCR is unknown.

Objective

To compare the rates of complete biochemical responses after testosterone recovery after 8 mo of AAP and degarelix, a gonadotropin-releasing hormone antagonist, alone or in combination.

Design, setting, and participants

Patients with BCR (prostate-specific antigen [PSA] ≥1.0 ng/ml, PSA doubling time ≤9 mo, no metastases on standard imaging, and testosterone ≥150 ng/dl) after prostatectomy (with or without prior radiotherapy) were included in this study.

Intervention

Patients were randomized to AAP (arm 1), AAP with degarelix (arm 2), or degarelix (arm 3) for 8 mo, and monitored for 18 mo.

Outcome measurements and statistical analysis

The primary endpoint was undetectable PSA with testosterone >150 ng/dl at 18 mo. Secondary endpoints were undetectable PSA at 8 mo and time to testosterone recovery.

Results and limitations

For the 122 patients enrolled, no difference was found between treatments for the primary endpoint (arm 1: 5.1% [95% confidence interval {CI}: 1–17%], arm 2: 17.1% [95% CI: 7–32%], arm 3: 11.9% [95% CI: 4–26%]; arm 1 vs 2, p = 0.93; arm 2 vs 3, p = 0.36). AAP therapy showed the shortest median time to testosterone recovery (36.0 wk [95% CI: 35.9–36.1]) relative to degarelix (52.9 wk [95% CI: 49.0–56.0], p < 0.001). Rates of undetectable PSA at 8 mo differed between AAP with degarelix and degarelix alone (p = 0.04), but not between AAP alone and degarelix alone (p = 0.12). Limitations of this study include a lack of long-term follow-up.

Conclusions

Rates of undetectable PSA levels with testosterone recovery were similar between arms, suggesting that increased androgen suppression with AAP and androgen deprivation therapy (ADT) is unlikely to eradicate recurrent disease compared with ADT alone.

Patient summary

We evaluated the use of abiraterone acetate plus prednisone (AAP) and androgen deprivation therapy (ADT), AAP alone, or ADT alone in men with biochemically recurrent, nonmetastatic prostate cancer. While more men who received the combination had an undetectable prostate-specific antigen (PSA) level at 8 mo on treatment, once men came off treatment and testosterone level rose, there was no difference in the rates of undetectable PSA levels. This suggests that the combination is not able to eradicate disease any better than ADT alone.

Phase III study of local or systemic therapy INtensification DIrected by PET in prostate CAncer patients with post-prostaTEctomy biochemical recurrence (INDICATE): ECOG-ACRIN EA8191

TPS5098

Background: Radiation therapy (RT) to the prostate bed and pelvic nodes with short-term androgen deprivation therapy (STAD) is considered a standard of care (SOC) salvage therapy (ST) paradigm for prostate cancer (PC) patients (pts) with post-prostatectomy (RP) biochemical recurrence (BCR). Fluciclovine-PET/CT imaging is FDA-approved in this setting, with improved accuracy for detection of metastases not identified with conventional imaging (CIM). Given PET's greater sensitivity and specificity, its findings are increasingly but variably applied to justify modification or omission of SOC therapies without high-level evidence of clinical benefit. PET may help identify candidates for local or systemic treatment intensification of the otherwise non-tailored SOC approach. Improved systemic control and disease detection with molecular imaging have led to increasing use of focally ablative metastasis-directed RT, to delay or enhance systemic therapy through increased local control. There is also interest in earlier use of systemic therapy; apalutamide (Apa) is a nonsteroidal antiandrogen with established efficacy in improving overall and radiographic progression-free survival (PFS) for non-metastatic castration-resistant and metastatic castration-sensitive PC. This study will evaluate whether pts with PET-detected lesions benefit from such local or systemic treatment intensification approaches. Methods: PC pts with post-RP BCR (PSA>0.5ng/mL; >0.2ng/mL if within 12 mos of RP) and no metastases on CIM who are candidates for SOC ST (RT to prostate bed and pelvic nodes with STAD) are eligible. Prior to study registration, pts undergo SOC baseline PET (18F-fluciclovine but PSMA radiotracers permitted pending commercial availability). Based on institutional clinical interpretation of the SOC PET, pts will be placed in Cohort 1 (PET-negative) or 2 (PET-positive for extra-pelvic metastases). Cohort 1 will be randomized to SOC ST +/- Apa for 6 months and Cohort 2 will be randomized to SOC ST and Apa +/- metastasis-directed RT to PET-positive lesions. The primary endpoint is PFS, defined as time from randomization to radiographic progression on CIM, symptomatic disease or death. Primary objectives are to evaluate whether addition of Apa to SOC ST and addition of metastasis-directed RT to SOC ST and Apa could prolong PFS in Cohorts 1 and 2, respectively. For Cohort 1, 480 pts will be randomized with 85% power to distinguish 5-year PFS rate of 90% (Apa arm) vs. 80% (SOC arm) using one-sided stratified log-rank test with type I error of 0.025. For Cohort 2, 324 pts will be randomized with 85% power to distinguish 5-year PFS rate of 76.5% in the experimental arm from 61.5% in the control arm. Secondary endpoints include overall and event-free survival, toxicity, and PET progression. Clinical trial information: NCT04423211.

PET-directed local or systemic therapy intensification in prostate cancer patients with post-prostatectomy biochemical recurrence: A trial of the ECOG-ACRIN Cancer Research Group (EA8191)

TPS267

Background: Radiation therapy (RT) to the prostate bed and pelvic nodes with short-term androgen deprivation therapy (STAD) is considered a standard of care (SOC) salvage therapy (ST) paradigm for prostate cancer (PC) patients (pts) with post-prostatectomy (RP) biochemical recurrence (BCR). Fluciclovine-PET/CT imaging is FDA-approved in this setting, with improved accuracy for detection of metastases (mets) not identified with conventional imaging (CIM). Given greater sensitivity and specificity of PET, its findings are being increasingly but variably applied to justify modification or omission of SOC therapies without high-level evidence of clinical benefit. PET may help identify candidates for local or systemic treatment intensification of otherwise non-tailored SOC. Earlier detection of mets with molecular imaging has led to increasing use of focally ablative met-directed RT, to delay or enhance systemic therapy through better local control. There is also interest in earlier use of advanced systemic therapy; apalutamide (Apa) is a nonsteroidal antiandrogen with established efficacy in improving overall and radiographic progression-free survival (PFS) for non-metastatic castrate-resistant and metastatic castration-sensitive PC, and potential activity for low-volume mets. This study will evaluate whether pts with PET-detected lesions benefit from such local or systemic treatment intensification approaches. Methods: PC pts with post-RP BCR (PSA>0.5ng/mL; >0.2 if RP within 12 mos), and negative CIM who are candidates for SOC ST (RT to prostate bed and pelvic nodes + STAD) and undergo SOC baseline PET are eligible. The study will initially use 18F-fluciclovine but permit additional radiotracers based on FDA approval and availability. Based on institutional clinical interpretation of the SOC PET, pts will be placed in Cohort 1 (PET-negative) or 2 (PET-positive for extra-pelvic mets). Cohort 1 will be randomized to SOC ST +/- Apa for 6 months and Cohort 2 will be randomized to SOC ST and Apa +/- met-directed RT to PET-positive lesions. The primary endpoint is PFS, defined as time from randomization to radiographic progression on CIM, symptomatic disease or death. Primary objectives are to evaluate whether addition of Apa to SOC ST and addition of met-directed RT to SOC ST and Apa could prolong PFS in Cohorts 1 and 2, respectively. For Cohort 1, 480 pts will be randomized with 85% power to distinguish 5-year PFS rate of 90% (Apa arm) vs. 80% (SOC arm) using one-sided stratified logrank test with type I error of 0.025. For Cohort 2, 324 pts will be randomized with 85% power to distinguish 5-year PFS rate of 76.5% in experimental arm from 61.5% in control arm. Secondary endpoints include overall and event-free survival, toxicity, and PET progression. Trial was activated on October 8, 2020; NCT04423211. Acknowledgement: This study was conducted by the ECOG-ACRIN Cancer Research Group (Peter J. O'Dwyer, MD and Mitchell D. Schnall, MD, PhD, Group Co-Chairs) and supported by the National Cancer Institute of the National Institutes of Health under the following award numbers: U10CA180794, U10CA180820, U10CA180868, U10CA180888, U10CA180821, UG1CA233196, UG1CA233253, UG1CA233277, UG1CA233328, and UG1CA233330. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. government. Clinical trial information: NCT 04423211.

Associations of circulating cell-free DNA (cfDNA) and clinical outcomes in metastatic castrate-resistant prostate cancer (mCRPC)

137

Background: Genomic profiling of patients (pts) with mCRPC is becoming more widely utilized to assist in prognosis and treatment. Liquid biopsies offer a non-invasive method of assessing gene alterations but questions remain regarding their validity, as well as the association of these alterations with relevant clinical outcomes. Methods: We present a retrospective analysis of 82 pts who underwent genomic profiling at the onset of mCRPC using the Guardant360 cfDNA assay. Clinical outcomes data was recorded in a structured note in the electronic medical record that allowed discrete data elements to be stored and analyzed. Patients received standard treatment with Abiraterone (Abi) and Enzalutamide (Enza) as well as chemotherapy. Relevant clinical outcome endpoints included overall survival (OS) and time on treatment with Abi and Enza (TT). These endpoints were compared between patients grouped by their gene alterations and treatment. Univariate and multivariate association analyses were performed. Results: The structured note was found to be valuable in capturing relevant discrete clinical outcomes data for detailed analysis. Median OS for the 82 pts was 58 months. 15 pts had insufficient cfDNA to perform the assay and these pts had a significantly longer OS than the 67 pts with sufficient cfDNA (median not reached vs 36 months, p = 0.004). The most commonly altered genes were AR and TP53 with 45% pts having alterations in both genes. Our analysis showed significantly shorter OS with BRAF (24 months, p = 0.008) and NF1 (20 months, p = 0.036) alterations. However, the significance was lost after multiple hypothesis correction. We observed that pts with co-occurrence of AR and BRAF had a significantly shorter OS (18.7 months, p = 0.031). BRCA2 mutations were observed in 9 pts and were associated with a significantly shorter TT (23 vs 38 months, p = 0.022) but lost significance after multiple hypothesis correction. Patients who received Abi followed by Enza had a significantly longer TT compared to pts who received the reverse sequence (38 months vs 23 months, p = 0.02). Conclusions: In this retrospective analysis, we did not identify any significant associations between specific gene alterations and relevant clinical outcomes. We observed a trend of shorter OS with BRAF and NF1 alterations and a shortened OS with co-occurrence of AR and BRAF alterations. These associations will require validation in a larger study. The presence of sufficient DNA to perform the assay was associated with shorter OS. The treatment sequence of Abi followed by Enza showed longer TT than the reverse sequence. The structured note allowed capture of relevant clinical outcomes data and is currently being utilized in a larger prospective genomic study of mCRPC.

Phase I/II trial of enzalutamide (Enz) plus mifepristone (Mif) for metastatic castration-resistant prostate cancer (mCRPC)

91

Background: Resistance to androgen receptor (AR) targeted therapies is common in mCRPC. Glucocorticoid receptor (GR) expression increases with AR inhibition in patients (pts) and blockade of GR signaling inhibits CRPC growth in preclinical models when combined with AR blockade. We thus conducted a phase I/II open label trial of Enz combined with Mif, a GR, AR, and progesterone receptor antagonist for pts with mCRPC to assess the feasibility and impact on disease progression with dual AR/GR antagonism. Methods: The phase I dose escalation portion assessed the safety of the two-drug combination and a recommended phase II dose (R2PD) was determined based on safety, pharmacokinetic and endocrine assessments. In the phase II portion, patients (pts) received 12 weeks of Enz (160mg/day) followed by randomization to Enz alone or Enz plus Mif with PSA-progression free survival (PFS) as the primary endpoint. 42 pts were to randomize to each arm to provide 80% power to detect a hazard ratio of 0.6, with a one-sided alpha of 0.1; there was a planned interim futility analysis after 50% of progression events. Results: 106 pts (18 phase I/88 phase II) were enrolled. Pts had a median age of 70 (range 53-89) and baseline PSA of 12.8 (range 0.1-755). 34% of pts received prior docetaxel. The RP2D was 120mg/day Enz and 300mg/day Mif. In phase II, 33 patients were randomized to each arm, with well-balanced baseline demographics. 22 pts were not randomized (15 due to disease progression, 2 due to toxicity, and 5 due to the interim study analysis). The interim analysis showed no difference between arms in PSA-PFS (hazard ratio = 1.34, p=0.395), 12-month PSA-PFS of 31% in both arms, and per-protocol, the trial was stopped. Toxicities were similar in the arms, e.g. fatigue (12% vs. 14%), hot flashes (6% vs. 5%), and pain (4% vs. 4%). Conclusions: The addition of Mif to Enz following a 12-week Enz lead-in did not delay time to PSA progression. Further analyses of secondary endpoints, including translational biomarkers such as hormone levels, GR/AR-v7 expression in circulating tumor cells and cell free DNA analyses are ongoing. Clinical trial information: NCT02012296.

Immune checkpoint inhibitor toxicity in the clinical practice setting

e14128

Background: Immune checkpoint inhibitors (ICIs) are changing the landscape of treatment in oncology. The use of ICIs is growing rapidly as the indications for these medications broaden and new ICIs become approved. Given the rapid growth and relative infancy of the use of ICIs, much information stands to be gained on their use in the clinical practice setting, especially regarding toxicity. Methods: The primary objective of this project was to examine the incidence and severity of immune-related adverse events (irAEs), after treatment with single-agent or combination ICIs at a multi-site community cancer center. A retrospective chart review was conducted on all patients who had received ipilimumab, nivolumab, pembrolizumab, atezolizumab, or ipilimumab plus nivolumab from May 1, 2011 to June 30, 2017. Data collected included patient demographics, disease state, treatment information, preexisting autoimmune disease, previous immunotherapy, and adverse event details. The results were analyzed using descriptive statistics. Results: Data was collected on 383 patients. Dermatologic irAEs were common across single agent ICIs (overall incidence 23%). Diarrhea and/or colitis incidence was highest with CTLA-4 inhibitor ipilimumab (26% at 3 mg/kg and 22% at 10 mg/kg) versus the other monotherapy PD-1/PDL-1 inhibitors. Endocrinopathies were most common with ipilimumab 10 mg/kg (55%) and pneumonitis incidence was highest with nivolumab (6%). ICI toxicity occurred in 63% of patients with preexisting autoimmune disease versus 54% of those without a baseline autoimmune disease. Incidence of hospitalization and treatment holds due to irAEs was higher with combination therapy (57% and 66%, respectively) than with monotherapy (10% and 24%, respectively). Conclusions: Overall, there was increased incidence in ICI toxicity in patients at this oncology institution versus what has been reported in clinical trials. Patients with preexisting autoimmune diseases appeared to have mainly low-grade toxicities with slightly increased incidence of irAE compared with those without pre-existing autoimmune disease. Treatment holds and hospitalizations were higher in patients treated with combination therapy ICIs compared to monotherapy ICIs.

Evaluation of the patient-reported outcomes common terminology criteria for adverse events (PRO-CTCAE) with abiraterone acetate plus prednisone (AAP), degarelix (D), or the combination in men with biochemically recurrent prostate cancer (BCRPC)

5080

Background: Patient-reported symptoms using the PRO-CTCAE provide insights into the patient experience with care. Earlier use of AAP (an androgen biosynthesis inhibitor plus prednisone) with androgen deprivation therapy in castration sensitive disease may lead to increased symptoms. We previously reported a randomized phase 2 trial of intermittent AAP, D, or AAP+D in BCRPC (NCT01751451) and now share the PRO-CTCAE results. Methods: Men were randomized 1:1:1 to AAP, D, or AAP+D for 8 months, then entered follow up with PSA, testosterone, and safety monitoring. PRO-CTCAE was elicited from patients monthly for hot flashes (HF), fatigue, arthralgias, myalgias, anxiety, depression, sexual function, plus overall QOL. Changes from baseline to end of treatment were compared between groups. AUCs were calculated for each item as a measure of symptom severity over time. Results: 110 men were included. Compliance with PRO-CTCAE reporting from baseline to EOT was 93%. HF did not differ between AAP+D and D, but were increased relative to AAP (all p < 0.05). These differences were consistent when HF were measured as an AUC (all p < 0.01). Fatigue severity did not differ between groups however men receiving AAP reported a small worsening in activity interference from fatigue as compared to AAP+D (p < 0.05). Overall QOL scores were high and did not differ with AAP+D relative to AAP or D. Conclusions: Collection of PRO-CTCAE was feasible and did not demonstrate differences in fatigue, HF, or QOL between AAP+D and D. Comparisons of PRO-CTCAE to matched clinician-reported AEs, and changes in PRO-CTCAE with testosterone recovery during follow up are planned. Clinical trial information: NCT01751451.

Response rate to chemotherapy after disease progression with anti-PD-1/PD-L1 in metastatic cancer

e14088

Background: The checkpoint inhibitor (CPI) immunotherapy class of drugs is redefining how we treat cancer. The US FDA has approved CPI drugs as 1st, 2nd or salvage line after progression on conventional chemotherapy (CTX) for multiple cancers including melanoma, lung, bladder and other cancers. However, many questions remain regarding optimal treatment post-progression. Indeed, it has been noted that the patterns of response and relapse to CPI agents are quite different from those of standard cytotoxic agents and that response to CTX AFTER CPI may be different than in the de novo setting. The purpose of this retrospective analysis is to evaluate the activity (response rate (RR), response duration (DOR) and progression free survival (PFS)) of subsequent CTX after disease progression following treatment with CPI. Methods: In this analysis, patients (pts) were enrolled under an IRB approved waiver of consent. We identified pts treated with CPI agents between Jan, 2011 and Dec, 2018 at a multi-site community cancer program who received subsequent CTX as a result of disease progression (PD). We assessed the RECIST RR to subsequent therapy, DOR from onset of response, and PFS from the onset of post CPI CTX, identifying index lesions from the most recent pre-treatment anatomic scan. Results: A total of 47 cases satisfying the above criteria were found; 31 NSCLC, 8 melanoma, 1 SCLC, 1 GEJ, 1 gastric, 2 head/neck, 1 large cell neuroendocrine tumor, 2 bladder cancer. 25 pts had PD as best response to post-CPI CTX. 9 pts (19%) achieved a partial response (PR) with a median DOR of 99 days. 22 pts achieved a PR or stable disease (SD) for a clinical benefit (CB) rate of 47%. The median duration of CB was 92 days. Of the 9 patients who achieved PR, 5/6 had achieved response to CTX prior to CPI . The median PFS for the entire cohort was 97 days. Conclusions: While an expected RR could not be calculated in this heterogenous group of pts, the number and degree of responses suggests CPI possible “priming” that may enhance response to CTX. Post-CPI CTX may be of value and in this retrospective study of a heterogenous group of pts, responses may be more frequent than expected. A larger further study is warranted.

Final analysis of a phase II study of MRI based functional imaging of bone metastases in men with metastatic castrate-resistant prostate cancer (mCRPC) receiving cabozantinib

213

Background: Cabozantinib (C) is a small molecule inhibitor of receptor tyrosine kinases including VEGFR-2, c-MET. C trials have shown significant improvements in bone pain and bone scintigraphy in mCRPC patients (pts). We hypothesized that functional imaging using MRI could elucidate underlying biological processes by demonstrating an early decrease in vascular permeability (decrease in transfer consant - Ktrans) and subsequent decrease in cell density (increase in apparent diffusion coefficient - ADC) within bone metastases. Methods: mCRPC pts received C 60 mg daily. The primary endpoint was change in Ktrans at 2 weeks (wks) of treatment. Secondary endpoints included Ktrans and ADC longitudinal changes, and correlation with bone scan, PSA, RECIST, and changes in reported pain. All pts underwent MRI at baseline, day 0, day 15 and every 12 wks. Results: 17 pts were treated at two sites. Median age: 68 yrs (range:51-83), baseline PSA 94.78 ng/mL (7.4-2971), number of prior CRPC therapies 2 (1-8). Median progression free survival was 5.1 months; 5 pts discontinued therapy for adverse events, and 12 for progressive disease. The most common grades 3/4 toxicities were fatigue (24%) and palmarplantar erythrodysesthesia (12%). 14 pts were evaluable for the primary endpoint. At 2 wks, Ktrans decreased an average 35%, 0.074 to 0.048 min-1 (SD=0.016, p<0.0001). There was no change in Ktrans between wk 2 and end of study. There was an increase in median ADC of 150 at wk 12. There were no RECIST or 50% PSA responses. Conclusions: Ktrans decreased significantly after 2 wks of treatment, consistent with antiangiogenic properties of C. Compared to wk 2, K trans at disease progression is unchanged, which could signify that adaptive vascular change is not the primary mechanism of tumor resistance to the drug. Contrary to our hypothesis, ADC increased during the trial, which perhaps correlates with the short median time to progression. Still, MRI of bone metastases could benefit drug development for other agents in mCRPC or interrogation of bone metastases, notoriously challenging for disease response analysis, in other cancers. Clinical trial information: NCT01599793.

Chemohormonal Therapy in Metastatic Hormone-Sensitive Prostate Cancer: Long-Term Survival Analysis of the Randomized Phase III E3805 CHAARTED Trial

Purpose Docetaxel added to androgen-deprivation therapy (ADT) significantly increases the longevity of some patients with metastatic hormone-sensitive prostate cancer. Herein, we present the outcomes of the CHAARTED (Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer) trial with more mature follow-up and focus on tumor volume. Patients and Methods In this phase III study, 790 patients with metastatic hormone-sensitive prostate cancer were equally randomly assigned to receive either ADT in combination with docetaxel 75 mg/m2 for up to six cycles or ADT alone. The primary end point of the study was overall survival (OS). Additional analyses of the prospectively defined low- and high-volume disease subgroups were performed. High-volume disease was defined as presence of visceral metastases and/or ≥ four bone metastases with at least one outside of the vertebral column and pelvis. Results At a median follow-up of 53.7 months, the median OS was 57.6 months for the chemohormonal therapy arm versus 47.2 months for ADT alone (hazard ratio [HR], 0.72; 95% CI, 0.59 to 0.89; P = .0018). For patients with high-volume disease (n = 513), the median OS was 51.2 months with chemohormonal therapy versus 34.4 months with ADT alone (HR, 0.63; 95% CI, 0.50 to 0.79; P < .001). For those with low-volume disease (n = 277), no OS benefit was observed (HR, 1.04; 95% CI, 0.70 to 1.55; P = .86). Conclusion The clinical benefit from chemohormonal therapy in prolonging OS was confirmed for patients with high-volume disease; however, for patients with low-volume disease, no OS benefit was discerned.

Targeting Androgen Receptor and DNA Repair in Metastatic Castration-Resistant Prostate Cancer: Results From NCI 9012

Purpose To determine whether cotargeting poly (ADP-ribose) polymerase-1 plus androgen receptor is superior to androgen receptor inhibition in metastatic castration-resistant prostate cancer (mCRPC) and whether ETS fusions predict response. Patients and Methods Patients underwent metastatic site biopsy and were stratified by ETS status and randomly assigned to abiraterone plus prednisone without (arm A) or with veliparib (arm B). Primary objectives were: confirmed prostate-specific antigen (PSA) response rate (RR) and whether ETS fusions predicted response. Secondary objectives were: safety, measurable disease RR (mRR), progression-free survival (PFS), and molecular biomarker analysis. A total of 148 patients were randomly assigned to detect a 20% PSA RR improvement. Results A total of 148 patients with mCRPC were randomly assigned: arm A, n = 72; arm B, n = 76. There were no differences in PSA RR (63.9% v 72.4%; P = .27), mRR (45.0% v 52.2%; P = .51), or median PFS (10.1 v 11 months; P = .99). ETS fusions did not predict response. Exploratory analysis of tumor sequencing (80 patients) revealed: 41 patients (51%) were ETS positive, 20 (25%) had DNA-damage repair defect (DRD), 41 (51%) had AR amplification or copy gain, 34 (43%) had PTEN mutation, 33 (41%) had TP53 mutation, 39 (49%) had PIK3CA pathway activation, and 12 (15%) had WNT pathway alteration. Patients with DRD had significantly higher PSA RR (90% v 56.7%; P = .007) and mRR (87.5% v 38.6%; P = .001), PSA decline ≥ 90% (75% v 25%; P = .001), and longer median PFS (14.5 v 8.1 months; P = .025) versus those with wild-type tumors. Median PFS was longer in patients with normal PTEN (13.5 v 6.7 months; P = .02), TP53 (13.5 v 7.7 months; P = .01), and PIK3CA (13.8 v 8.3 months; P = .03) versus those with mutation or activation. In multivariable analysis adjusting for clinical covariates, DRD association with PFS remained significant. Conclusion Veliparib and ETS status did not affect response. Exploratory analysis identified a novel DRD association with mCRPC outcomes.

Abiraterone + prednisone (Abi) +/- veliparib (Vel) for patients (pts) with metastatic castration-resistant prostate cancer (CRPC): NCI 9012 updated clinical and genomics data

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Background: In preclinical CRPC models, PARP1 inhibition synergizes with AR targeted therapy, especially in ETS fusion-positive tumors. We hypothesized: 1. Co-targeting PARP-1 + AR is superior to AR inhibition and 2. ETS +ve predicts response. Methods: Pts had metastatic (mets) disease biopsy (bx), stratified by IHC-ETS status and randomized to Abi (Arm A) or Abi + Vel (Arm B). Primary endpoint: PSA response rate (RR > = 50% decline). Secondary endpoints: safety, objective RR (ORR), progression free survival (PFS), and molecular analysis including if DNA repair gene deficiency (DRD: BRCA 1, BRCA 2, ATM, FANCA, PALB2, RAD51B, RAD51C) predicts response. 148 pts stratified by IHC-ETS status were randomized to detect a 20% PSA RR improvement assuming a 5% 1-sided type I error and 80% power. An elastic net multivariable Cox model was used to analyze PFS. Mets bx underwent targeted exon sequencing and capture transcriptome analysis. Results: 72 pts were randomly assigned to Arm A and 76 to Arm B. PSA RR: Arm A 63.9%, Arm B 72.4% (p = 0.27). ORR: Arm A 45%, Arm B 52.2%, p = 0.51. Median PFS: Arm A 10.1 months (m), Arm B 11.3 m, p = 0.95. More Arm-B pts were on therapy for 12+ (45% vs 38%) and 18+ cycles (22% vs 17%). ETS status had no impact. Mets tissue sequencing (N = 80): 42 pts (53%) were ETS +ve, 19 (25%) had DRD, 47 (59%) had AR amplification/copy gain, 32 (40%) had PTEN mutation (mut), 33 (41%) had TP53 mut, 37 (46%) had PIK3CA activation (a) and 12 (15%) had WNT-a. Irrespective of arm pts with DRD had a higher PSA and ORR ( > = 87%) vs wild type (58%, 39%; p = 0.013, p = 0.002, respectively), higher PSA decline rate of > = 90% (74% vs 26%, p = 0.0004) and longer median PFS (95% CI): DRD 16.6 m (11 - NR) vs wild type: 8 m (5.4 – 13.3); p = 0.02. PFS was longer in pts with normal PTEN (13.5 vs 6.2 m, p = 0.02), TP53 (13.3 vs 7.8 m, p = 0.04) and PIK3CA (10.3 vs 8.3 m, p = 0.03). Controlling for clinical factors, DRD, PTEN, TP53 and PIK3CA are associated with PFS in this order of importance. Conclusions: There was a modest trend in favor of Abi + Vel but no difference by ETS. Pts with DRD, normal PTEN,TP53 and PIK3CA had better PFS raising new hypotheses regarding the importance of integrating molecular analysis in therapeutic trials. Clinical trial information: NCT01576172.

Validation of the total illness burden index for prostate cancer (TIBI-CaP) in men with castration-resistant prostate cancer (CRPC): Data from TRUMPET

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Background: The TRUMPET registry is a prospective, observational cohort study of patients (pts) with CRPC designed to evaluate treatment patterns and health-related quality of life (HRQoL) outcomes associated with CRPC and its management in a real-world setting. Comorbidities may influence how physicians approach CRPC treatment; therefore, evaluation of comorbidity presence and severity is important. The TIBI-CaP questionnaire measures comorbidity, with the aim of this analysis to validate TIBI-CaP in CRPC. Methods: Data were collected from 302 enrolled CRPC pts treated in academic and community-based sites under routine care. Baseline data collected included clinical history and self-reported demographics, comorbidities, and HRQoL. TIBI-CaP scores were analyzed based on correlation analysis and analysis of variance (ANOVA). Estimated correlations were used to verify the association of TIBI-CaP scores to scores on the SF-12v2 and FACT-P questionnaires. ANOVA models were run with SF-12v2 and FACT-P as response and quartile ranges for TIBI-CaP scores as predictor. Results: Mean age was 73.7 years. 84.7% were white; 13.9% were black. 87.8% had M1 CRPC at study entry. Mean (SD) TIBI-CaP score was 5.3 (2.72) [range 0-13], with 42.4% of CRPC pts presenting with moderate/severe comorbidity burden (higher scores). TIBI-CaP scores had statistically significant (p value < 0.0002) negative correlations with all SF-12v2 composite and domain scores. Correlation estimates for physical condition and mental condition scores were -0.46 and -0.23, respectively. TIBI-CaP scores also had statistically significant (p value < 0.02) negative correlations with FACT-P total scores and all subscales. FACT-P total scores had a -0.44 correlation estimate. F-tests showed significant differences across the four quartiles of TIBI-CaP scores and SF-12v2 and FACT-P (all p values < 0.05). Conclusions: At baseline, TIBI-CaP scores were negatively correlated with CRPC pts baseline functional status as measured by the SF-12v2 and FACT-P questionnaires. TIBI-CaP was strongly associated with HRQoL physical subscales. This analysis demonstrates validity of TIBI-CaP in CRPC pts.

Effects of radium-223 (Ra-223) with docetaxel versus docetaxel alone on bone biomarkers in patients with bone-metastatic castration-resistant prostate cancer (CRPC): A phase I/IIa clinical trial

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Background: Interactions between metastatic prostate cancer cells, osteoblasts, osteoclasts, and other participants in bone metabolism are complex and result in pathologic bone physiology. Ra-223, a targeted alpha therapy, accumulates at sites of bone metastases and prolongs survival. Ra-223 and docetaxel (D), acting through different mechanisms of action, may have beneficial effects on bone pathophysiology and tumor microenvironment. Prior data suggest treatment with Ra-223 results in favorable alterations in bone biomarkers that are associated with survival. Methods: 53 patients with progressing CRPC and ≥ 2 bone metastases were randomized 2:1 to Ra-223 (55 kBq/kg q6wk × 5) + D (60 mg/m2 q3wk × 10) versus D (75 mg/m2 q3wk with step-down option to 60 mg/m2). Bone resorption (CTX-1, ICTP) and formation (P1NP, bALP) markers, tALP, and PSA were analyzed at wk 19 (after 3 Ra-223 injections) and 3 wk after end of treatment (EOT). Results: Mean % change at wk 19 and EOT are shown (Table). tALP, bALP, P1NP, and PSA declined early during treatment, reaching an average of > 30% decline from baseline by wk 19 in both arms. Mean % declines were greater in the Ra-223 + D versus the D-alone arm at wk 19 and EOT. Bone resorption markers CTX-1 and ICTP showed little decline at wk 19. Conclusions: Ra-223 + D patients had greater % decline in tALP and in bone formation markers bALP and P1NP. Due to small patient numbers and preliminary data, further analysis and correlation with clinical outcomes in a larger study is warranted. Clinical trial information: NCT01106352. [Table: see text]

Genetic polymorphisms to predict progression-free survival in patients with metastatic castration-resistant prostate cancer (mCRPC) receiving abiraterone therapy: Results from the NCI 9012 trial

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Background: Abiraterone is a CYP17 inhibitor approved for treatment of men with mCRPC. The NCI 9012 trial evaluated abiraterone alone with or without the PARP inhibitor veliparib in mCRPC patients. We hypothesized that germline genetic variation in the androgen axis and other metabolic enzymes would predict response to veliparib + abiraterone vs. abiraterone alone. Methods: A randomized trial cohort of (148) men with advanced mCRPC treated with abiraterone with or without veliparib was genotyped for 120 DNA polymorphisms in genes involved in androgen metabolism using Lifetech Open array chips. Blood for pharmacogenomic SNP analysis were collected at pre-treatment from each subject into 10-mL EDTA tube. Polymorphisms were tested using Cox models without treatment for prognostic testing and with treatment arm for predictive testing. Results: Genotyping was completed in 143 of 148 men; all were treated with abiraterone; 72 without veliparib (Median PFS: 10.3m) and 71 with veliparib (Median PFS: 11.3m). Polymorphisms in separate genes (SLCO2B1, KIF3C CYP19A, ESR1) were significantly (P ≤ .025) associated with progression-free survival (PFS) during abiraterone (q-value < 0.69). Polymorphisms in (CYP11A1, HSD17B4, ABHD13;LIG4, CYP19A1, HSD17B4, TRMT11) were predictive for PFS in patients treated with combination of abiraterone/veliparib compared to abiraterone alone (p-value < 0.025; q-value < 0.28). Conclusions: This analysis examines the influence of inherited variations on the efficacy of abiraterone, establishing the importance of pharmacogenomics on individual’s response to this therapy. Genotyping patients at these loci could be predictive of improved PFS to valiparib in combination with abiraterone. Further analysis of the association of more than one polymorphisms compared to zero or one with PFS associated with improved TTP demonstrated a better response to therapy than individuals carrying zero or one is ongoing. Clinical trial information: NCT01576172.

Impact of metformin on prostate cancer (PC) outcomes in the E3805 CHAARTED trial

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Background: To evaluate whether metformin (Met) a widely-used, nontoxic oral antidiabetic drug with putative anticancer properties leads to improvements in prostate cancer (PC) outcomes in the CHAARTED trial. Methods: In the CHAARTED database where metformin use at baseline was recorded prospectively, we identified patients with metastatic PC who underwent either ADT alone or ADT and docetaxel (D) chemotherapy. Cox proportional hazards models were used to determine the effect of Metformin on outcomes. Results: A total of 788 patients (median age, 63 y) had complete data after randomization. Comparison of ADT+D+Met (n = 39) to ADT+D (n = 357) and ADT+Met (n = 29) to ADT alone (n = 363) revealed similar clinicopathologic characteristics. Cause of death was PC in 13(81%) of ADT+D+Met, 72(85%) ADT+D, 9(82%) ADT+Met and 105(84%) ADT alone groups. See table for PC outcomes and overall survival by metformin use. Cox regression analysis for overall survival stratified by stratification factors at randomization demonstrates Met use was associated with a trend for worse overall survival (HR 1.47 95%CI: [0.95,2.26], p = 0.08) with adjustment for treatment arm and prior local therapy. In contrast, ADT+D use (HR 0.62; 95%CI: [0.47,0.81]) and prior local therapy with surgery or radiation (HR 0.56; 95% CI: [0.38, 0.82]) were associated with improved survival. Conclusions: In this study, baseline metformin did not improve PC outcomes. Partial support and drug supply by Sanofi. Clinical trial information: NCT00309985. [Table: see text]

Lower PSA at 7 months is prognostic for improved overall survival (OS) in metastatic hormone sensitive prostate cancer (mHSPC) treated with ADT with and without docetaxel (D)

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Background: Prior work from SWOG 9346 revealed that PSA ≤ 0.2 ng/dL at 7 months (mo) is prognostic for longer OS with ADT alone. We sought to evaluate if this optimal decline remained predictive of better OS when D was added to ADT for initial mHSPC treatment. Methods: We performed a landmark survival analysis at 7 mo using the E3805 database (NCT00309985). Inclusion required at least 7 mo of followup and PSA levels at 7 mo from ADT initiation. Survival was defined from ADT start or randomization to death. SWOG 9346 PSA nadirs of ≤ 0.2, > 0.2-4 and > 4 were used as classifiers. Results: 719 patients were eligible for analysis: 358 treated with ADT plus D and 361 with ADT alone. Median follow-up was 23.1 mo. On multivariable analysis (MVA), achieving a PSA ≤ 0.2 at 7 mo was more likely if the patient received D and had lower volume disease, prior local therapy, and lower baseline PSAs (all p ≤ 0.01). Across all patients, median OS was significantly longer if PSA at 7 mo reached ≤ 0.2 compared to > 4 (p < 0.0001) (Table). On MVA, PSA ≤ 0.2 at 7 mo and low volume disease were prognostic of longer OS (all p < 0.01). On ADT, 28.8% achieved a PSA ≤ 0.2 at 7 mo vs. 45.3% on ADT+D. Patients on ADT alone who achieved a PSA nadir ≤ 0.2 had the best survival. These patients were more likely to have low volume disease (56.7%) compared to the ADT + D pts (46.3%). Conclusions: Achieving PSA ≤ 0.2 at 7 mo remains prognostic for longer OS with ADT for mHSPC, whether administered alone or with D. Adding D to ADT increased the likelihood of a lower PSA and improved survival. Partial support and drug supply by Sanofi. Clinical trial information: NCT00309985. [Table: see text]

Treatment registry for outcomes in patients with castration-resistant prostate cancer (TRUMPET): a methodology for real-world evidence and research

AIM

This study seeks to improve the understanding of treatment patterns and associated health-related quality of life (HRQoL), clinical outcomes and healthcare utilization in US patients with castration-resistant prostate cancer (CRPC).

PATIENTS & METHODS

Treatment Registry for Outcomes in CRPC Patients (TRUMPET) is a US-based, prospective, observational multicenter registry (NCT02380274) involving patients with CRPC and their caregivers. Patients initiating their first active treatment course will be enrolled from urology and medical oncology practices, with data captured up to 4 years.

RESULTS

Information on prescribing patterns, HRQoL, clinical outcomes and healthcare utilization will be collected.

CONCLUSION

TRUMPET will enable scientific understanding of disease management in terms of HRQoL, clinical outcomes and healthcare utilization in clinical practice for patients with CRPC.

Genomic predictors for treatment of late stage prostate cancer

In spite of the development of new treatments for late stage prostate cancer, significant challenges persist to match individuals with effective targeted therapies. Genomic classification using high-throughput sequencing technologies has the potential to achieve this goal and make precision medicine a reality in the management of men with castrate-resistant prostate cancer. This chapter reviews some of the most recent studies that have resulted in significant progress in determining the landscape of somatic genomic alterations in this cohort and, more importantly, have provided clinically actionable information that could guide treatment decisions. This chapter reviews the current understanding of common alterations such as alterations of the androgen receptor and PTEN pathway, as well as ETS gene fusions and the growing importance of PARP inhibition. It also reviews recent studies that characterize the evolution to neuroendocrine tumors, which is becoming an increasingly important clinical problem. Finally, this chapter reviews recent innovative studies that characterize the compelling evolutionary history of lethal prostate cancer evidenced by polyclonal seeding and interclonal cooperation between metastasis and the importance of tumor clone dynamics measured serially in response to treatment. The genomic landscape of late stage prostate cancer is becoming better defined, and the prospect for assigning clinically actionable data to inform rationale treatment for individuals with this disease is becoming a reality.