CREST: phase III study of sasanlimab and Bacillus Calmette-Guérin for patients with Bacillus Calmette-Guérin-naïve high-risk non-muscle-invasive bladder cancer

Bacillus Calmette-Guérin (BCG) is the standard of care for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of bladder tumor (TURBT). BCG in combination with programmed cell death-1 (PD-1) inhibitors may yield greater anti-tumor activity compared with either agent alone. CREST is a phase III study evaluating the efficacy and safety of the subcutaneous PD-1 inhibitor sasanlimab in combination with BCG for patients with BCG-naive high-risk NMIBC. Eligible participants are randomized to receive sasanlimab plus BCG (induction ± maintenance) or BCG alone for up to 25 cycles within 12 weeks of TURBT. The primary outcome is event-free survival. Secondary outcomes include additional efficacy end points and safety. The target sample size is around 1000 participants.

Complications of immuno-oncology care: what urologist should know

OBJECTIVES

To provide a practical review of immune-related adverse events (irAEs) that may be encountered in uro-oncology patients.

PATIENTS AND METHODS

We conducted a literature review of studies reporting irAEs including articles published through September 2023 for uro-oncology patients and the potential relevancy for the practicing urologist.

RESULTS

Immunotherapy has revolutionised cancer treatment, extending its impact to urological malignancies including for patients with urothelial, kidney, and prostate cancers. Immuno-oncology (IO) compounds have achieved measurable and durable responses in these cancers. Urologists, choosing to administer or co-manage IO patient care, should be prepared to understand, evaluate, and treat irAEs. This review discusses the spectrum of irAEs that can be encountered. Ongoing trials are exploring the use of immunotherapy at earlier stages of uro-oncological diseases, thus underscoring the evolving landscape of urological cancer treatment. Paradoxically, some data suggests that the occurrence of irAEs is associated with improved oncological outcomes.

CONCLUSIONS

Immune-related AEs, while manageable, may be life-threatening and require lifelong therapy. A thorough understanding of AEs and toxicity of a novel drug class is imperative.

A global phase II randomized trial comparing oral taxane ModraDoc006/r to intravenous docetaxel in metastatic castration resistant prostate cancer

STUDY AIM

ModraDoc006, an oral formulation of docetaxel, is co-administered with the cytochrome P450-3A4 and P-glycoprotein inhibitor, ritonavir (r): ModraDoc006/r. The preliminary efficacy and safety of oral ModraDoc006/r was evaluated in a global randomized phase II trial and compared to the current standard chemotherapy regimen of intravenous (i.v.) docetaxel and prednisone.

METHODS

103 mCRPC patients, chemotherapy-naïve with/without abiraterone and/or enzalutamide pretreated, with adequate organ function and evaluable disease per RECIST v1.1 and PCWG3 guidelines were randomized 1:1 into two cohorts. In Cohort 1, 49 patients received docetaxel 75 mg/m2 i.v. every 3 weeks (Q3W). In Cohort 2, 52 patients received ModraDoc006/r; 21 patients with a starting dose of ModraDoc006 30 mg with ritonavir 200 mg in the morning and ModraDoc006 20 mg with ritonavir 100 mg in the evening (30-20/200-100 mg) bi-daily-once-weekly (BIDW) on Days 1, 8, and 15 of a 21-day cycle. To alleviate tolerability, the starting dose was amended to ModraDoc006/r 20-20/200-100 mg in another 31 patients. All patients received prednisone 10 mg daily. Primary endpoint was rPFS.

RESULTS

There was no significant difference in rPFS between the 2 arms (p = 0.1465). Median rPFS was 9.5 months and 11.1 months (95% CI) for ModraDoc006/r and i.v. docetaxel, respectively. Partial response was noted in 44.1% and 38.7% measurable disease patients, and 50% decline of PSA was seen in 23 (50%) and 26 (56.5%) evaluable cases treated with ModraDoc006/r and i.v. docetaxel, respectively. The safety profile of ModraDoc006/r 20-20/200-100 mg dose was significantly better than i.v. docetaxel, with mild (mostly Grade 1) gastrointestinal toxicities, no hematologic adverse events, and neuropathy and alopecia incidence of 11.5% and 25%, respectively.

CONCLUSIONS

ModraDoc006/r potentially represents a widely applicable, convenient, effective, and better tolerated oral taxane therapy option for mCRPC. Further investigation of ModraDoc006/r in a large randomized trial is warranted.

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.

PATIENT SUMMARY

For patients with metastatic hormone-sensitive prostate cancer being treated with androgen deprivation therapy and docetaxel, PSA (prostate-specific antigen) became undetectable (below 0.2 ng/ml) in 67% of those also receiving darolutamide versus 29% of patients also receiving placebo. On average, patients achieving undetectable PSA lived longer than patients with detectable PSA.

Interruptions in bladder cancer care during the COVID-19 public health emergency

BACKGROUND

Academic and community urology centers participating in a pragmatic clinical trial in non-muscle-invasive bladder cancer completed monthly surveys assessing restrictions in aspects of bladder cancer care due to the COVID-19 Public Health Emergency. Our objective was to describe pandemic-related restrictions on bladder cancer care.

METHODS

We invited 32 sites participating in a multicenter pragmatic bladder cancer trial to complete monthly surveys distributed through REDCap beginning in May 2020. These surveys queried sites on whether they were experiencing restrictions in the use of elective surgery, transurethral resection of bladder tumors (TURBT), radical cystectomy, office cystoscopy, and intravesical bacillus Calmette-Guerin (BCG) availability. Responses were collated with descriptive statistics.

RESULTS

Of 32 eligible sites, 21 sites had at least a 50% monthly response rate over the study period and were included in the analysis. Elective surgery was paused at 76% of sites in May 2020, 48% of sites in January 2021, and 52% of sites in January 2022. Over those same periods, coinciding with COVID-19 incidence waves, TURBT was restricted at 10%, 14%, and 14% of sites, respectively, radical cystectomy was restricted at 10%, 14%, and 19% of sites, respectively, and cystoscopy was restricted at 33%, 0%, and 10% of sites, respectively.

CONCLUSIONS

Bladder cancer care was minimally restricted compared with more pronounced restrictions seen in general elective surgeries during the COVID-19 pandemic.

Transcriptome-Based Prognostic and Predictive Biomarker Analysis of ENACT: A Randomized Controlled Trial of Enzalutamide in Men Undergoing Active Surveillance

PURPOSE

Few studies have explored the potential for pharmacological interventions to delay disease progression in patients undergoing active surveillance (AS). This preplanned transcriptomic analysis of patient samples from the ENACT trial aims to identify biomarkers in patients on AS who are at increased risk for disease progression or who may derive the greatest benefit from enzalutamide treatment.

PATIENTS AND METHODS

In the phase II ENACT (ClinicalTrials.gov identifier: NCT02799745) trial, patients on AS were randomly assigned 1:1 to 160 mg orally once daily enzalutamide monotherapy or continued AS for 1 year. Transcriptional analyses were conducted on biopsies collected at trial screening, year 1, and year 2. Three gene expression signatures were evaluated in samples collected at screening and in available samples from patients on AS at any time during surveillance (expanded cohort): Decipher genomic classifier, androgen receptor activity (AR-A) score, and Prediction Analysis of Microarray 50 (PAM50) cell subtype signature.

RESULTS

The Decipher genomic classifier score was prognostic; higher scores were associated with disease progression in the expanded cohort and AS arm of the expanded cohort. Patients with higher Decipher scores had greater positive treatment effect from enzalutamide as measured by time to secondary rise in prostate-specific antigen >25% above baseline. In patients treated with enzalutamide, higher AR-A scores and PAM50 luminal subtypes were associated with a greater likelihood of negative biopsy incidence at year 2.

CONCLUSION

This analysis suggests that the Decipher genomic classifier may be prognostic for disease progression in AS patients with low- to intermediate-risk prostate cancer. Higher Decipher and AR-A scores, as well as PAM50 luminal subtypes, may also serve as biomarkers for treatment response.

First-line combination treatment with PARP and androgen receptor-signaling inhibitors in HRR-deficient mCRPC: Applying clinical study findings to clinical practice in the United States

INTRODUCTION

Metastatic castration-resistant prostate cancer (mCRPC) remains incurable and develops from biochemically recurrent PC treated with androgen deprivation therapy (ADT) following definitive therapy for localized PC, or from metastatic castration-sensitive PC (mCSPC). In the mCSPC setting, treatment intensification of ADT plus androgen receptor (AR)-signaling inhibitors (ARSIs), with or without chemotherapy, improves outcomes vs ADT alone. Despite multiple phase 3 trials demonstrating a survival benefit of treatment intensification in PC, there remains high use of ADT monotherapy in real-world clinical practice. Prior studies indicate that co-inhibition of AR and poly(ADP-ribose) polymerase (PARP) may result in enhanced benefit in treating tumors regardless of alterations in DNA damage response genes involved either directly or indirectly in homologous recombination repair (HRR). Three recent phase 3 studies evaluated the combination of a PARP inhibitor (PARPi) with an ARSI as first-line treatment for mCRPC: TALAPRO-2, talazoparib plus enzalutamide; PROpel, olaparib plus abiraterone acetate and prednisone (AAP); and MAGNITUDE, niraparib plus AAP. Results from these studies have led to the recent approval in the United States of talazoparib plus enzalutamide for the treatment of mCRPC with any HRR alteration, and of both olaparib and niraparib indicated in combination with AAP for the treatment of mCRPC with BRCA alterations.

SUMMARY

Here, we review the newly approved PARPi plus ARSI treatments within the context of the mCRPC treatment landscape, provide an overview of practical considerations for the combinations in clinical practice, highlight the importance of HRR testing, and discuss the benefits of treatment intensification for patients with mCRPC.

Patterns of treatment of high-risk BCG-unresponsive non-muscle invasive bladder cancer (NMIBC) patients among Arab urologists

PURPOSE

To understand the treatment plans suggested for BCG-unresponsive non-muscle invasive disease (NMIBC) patients in the Arab countries and therapeutic decisions applied for BCG-naive patients during BCG shortage time.

METHODS

A 10-minute online survey was distributed through the Arab Association of Urology (AAU) office to urologists in the Arab countries who treat patients with NMIBC.

RESULTS

One hundred six urologists responded to the survey. The majority of urologists had treated, in the past 6 months, > 10 patients with NMIBC who were considered BCG-unresponsive (55% of respondents). Radical cystectomy (RC) was the most popular treatment option (recommended by 50%) for these patients. This was followed by intravesical chemotherapy (30%), repeat BCG therapy (12%), resection with ongoing surveillance (8%). Clinical trials and intravenous checkpoint inhibitors were never selected. The most preferred intravesical chemotherapy was by ranking: 60% gemcitabine, 19% mitomycin C, 8% docetaxel, 8% gemcitabine/docetaxel, 4% sequential gemcitabine/mitomycin C, and 1% valrubicin. The use of intravesical chemotherapy appears limited by Arab urologists due to concerns regarding clinical efficacy (fear of progression) and the lack of clear recommendations by urology societies. Given the BCG shortage, which may vary per Arab country, Arab urologists have adjusted by prioritizing BCG for T1 and carcinoma in situ (CIS) patients over Ta, adapting intravesical chemotherapy, and reducing the dose/strength of BCG administered. Most physicians report an eagerness to utilize novel therapies to address the BCG deficit, especially to try intravesical chemotherapy.

CONCLUSIONS

Even though Arab urologists are in the majority of cases selecting RC for BCG-unresponsive cases, one-third of them are most recently initiating intravesical chemotherapy as an alternative option. To further assist Arab urologists in the appropriate selection of BCG unresponsive high risk NMIBC patient treatments, enhanced education and pathway protocols are needed.

Mechanism of action of nadofaragene firadenovec-vncg

Effective bladder-preserving therapeutic options are needed for patients with bacillus Calmette-Guérin unresponsive non-muscle-invasive bladder cancer. Nadofaragene firadenovec-vncg (Adstiladrin®) was approved by the US Food and Drug Administration as the first gene therapy in urology and the first intravesical gene therapy indicated for the treatment of adult patients with high-risk bacillus Calmette-Guérin-unresponsive non-muscle-invasive bladder cancer with carcinoma in situ with or without papillary tumors. The proposed mechanism of action underlying nadofaragene firadenovec efficacy is likely due to the pleiotropic nature of interferon-α and its direct and indirect antitumor activities. Direct activities include cell death and the mediation of an antiangiogenic effect, and indirect activities are those initiated through immunomodulation of the innate and adaptive immune responses. The sustained expression of interferon-α that results from this treatment modality contributes to a durable response. This review provides insight into potential mechanisms of action underlying nadofaragene firadenovec efficacy.

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.

Efficacy and Safety of Darolutamide in Combination With Androgen-Deprivation Therapy and Docetaxel in Black Patients From the Randomized ARASENS Trial

BACKGROUND

In the ARASENS trial (NCT02799602), darolutamide in combination with androgen-deprivation therapy (ADT) and docetaxel significantly reduced the risk of death by 32.5% (HR, 0.68; 95% CI, 0.57-0.80; P < .0001) compared with placebo plus ADT with docetaxel in patients with metastatic hormone-sensitive prostate cancer (mHSPC). We present efficacy and safety of darolutamide versus placebo in Black patients from ARASENS.

PATIENTS AND METHODS

Patients with mHSPC were randomized 1:1 to darolutamide 600 mg or placebo twice daily in combination with ADT and docetaxel. The primary endpoint was overall survival. Key secondary endpoints included time to castration-resistant prostate cancer (CRPC) and safety.

RESULTS

In ARASENS, 54 Black patients received darolutamide (n = 26) or placebo (n = 28) plus ADT and docetaxel. In Black patients, overall survival favored darolutamide versus placebo (median, not reached vs. 38.7 months; stratified HR, 0.41; 95% CI, 0.17-1.02), with 4-year survival rates of 62% versus 41%. The darolutamide group also had longer time to CRPC compared with the placebo group (median, not reached vs .12.6 months; HR, 0.09; 95% CI, 0.02-0.30). The safety profile of darolutamide in Black patients was consistent with that observed for the overall ARASENS population (grade 3/4 treatment-emergent adverse events, TEAEs: 61.5% vs. 66.1%; serious TEAEs: 42.3% vs. 44.8%).

CONCLUSION

In this small population of Black patients with mHSPC from the ARASENS trial, darolutamide was associated with an improvement in survival and time to CRPC and was well tolerated. Efficacy and safety findings in Black patients were consistent with the overall ARASENS population.

A multidisciplinary approach to address unmet needs in the management of patients with non-metastatic castration-resistant prostate cancer

BACKGROUND

With the availability of second-generation androgen receptor inhibitors (SGARIs), the treatment landscape has changed dramatically for patients with nonmetastatic castration-resistant prostate cancer (nmCRPC). In clinical trials, the SGARIs (apalutamide, enzalutamide, darolutamide) increased metastasis-free survival (MFS), overall survival (OS), and patient quality of life compared to placebo. These drugs were subsequently integrated into nmCRPC clinical practice guidelines. With advances in radiographic imaging, disease assessment, and patient monitoring, nmCRPC strategies are evolving to address limitations related to tracking disease progression using prostate-specific antigen (PSA) kinetics.

METHODS

A panel of 10 multidisciplinary experts in prostate cancer conducted reviews and discussions of unmet needs in the management and monitoring of patients with nmCRPC in order to develop consensus recommendations.

RESULTS

Across the SGARI literature, patient MFS and OS are generally comparable for all treatments, but important distinctions exist regarding short- and long-term drug safety profiles and drug-drug interactions. With respect to disease monitoring, a substantial proportion of patients using SGARIs may experience disease progression without rising PSA levels, suggesting a need for enhanced radiographic imaging in addition to PSA monitoring. Recent data also indicate that novel prostate-specific membrane antigen positron emission tomography radiotracers provide enhanced accuracy for disease detection, as compared to conventional imaging.

CONCLUSIONS

Clinical decision-making in nmCRPC has become more complex, with new opportunities to apply precision medicine to patient care. Multidisciplinary teams can ensure that patients with nmCRPC receive optimal and individualized disease management.

TALAPRO-3 clinical trial protocol: phase III study of talazoparib plus enzalutamide in metastatic castration-sensitive prostate cancer

Poly(ADP-ribose) polymerase inhibitors in combination with androgen-receptor signaling inhibitors are a promising therapeutic option for patients with metastatic castration-sensitive prostate cancer (mCSPC) and homologous recombination repair (HRR) gene alterations. Here, we describe the design and rationale of the multinational, phase III, TALAPRO-3 study comparing talazoparib plus enzalutamide versus placebo plus enzalutamide in patients with mCSPC and HRR gene alterations. The primary end point is investigator-assessed radiographic progression-free survival (rPFS) per RECIST 1.1 in soft tissue, or per PCWG3 criteria in bone. The TALAPRO-3 study will demonstrate whether the addition of talazoparib can improve the efficacy of enzalutamide as assessed by rPFS in patients with mCSPC and HRR gene alterations undergoing androgen deprivation therapy. Clinical Trial Registration:NCT04821622 (ClinicalTrials.gov) Registry Name: Study of Talazoparib With Enzalutamide in Men With DDR Gene Mutated mCSPC. Date of Registration: 29 March 2021.

Updates on Management of Biochemical Recurrent Prostate Cancer

OPINION STATEMENT

Patients with biochemical recurrent prostate cancer (BCR) are a heterogeneous group, whereby a personalized approach to management is critical. Patients with high-risk features such as PSA doubling time (PSADT) ≤ 9-12 months warrant earlier imaging for metastasis detection and consideration for intensified therapy (beyond intermittent androgen deprivation alone) during this phase of BCR-only disease. The BCR phase represents a unique opportunity to impact disease survival and delay metastasis progression. There is compelling evidence from the EMBARK trial that ADT monotherapy is no longer the optimal consideration for high-risk BCR patients.

Extended Safety and Tolerability of Darolutamide for Nonmetastatic Castration-Resistant Prostate Cancer and Adverse Event Time Course in ARAMIS

BACKGROUND

Patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) are usually asymptomatic and seek treatments that improve survival but have a low risk of adverse events. Darolutamide, a structurally distinct androgen receptor inhibitor (ARi), significantly reduced the risk of metastasis and death versus placebo in ARAMIS. We assessed the extended safety and tolerability of darolutamide and the time-course profile of treatment-emergent adverse events (TEAEs) related to ARis and androgen-suppressive treatment.

PATIENTS AND METHODS

Patients with nmCRPC were randomized 2:1 to darolutamide (n = 955) or placebo (n = 554). After trial unblinding, patients could receive open-label darolutamide. Tolerability and TEAEs were assessed every 16 weeks. Time interval-specific new and cumulative event rates were determined during the first 24 months of the double-blind period.

RESULTS

Darolutamide remained well tolerated during the double-blind and open-label periods, with 98.8% of patients receiving the full planned dose. The incidence of TEAEs of interest in the darolutamide group was low and ≤2% different from that in the placebo group, except for fatigue. When incidences were adjusted for exposure time, there were minimal differences between the darolutamide double-blind and double-blind plus open-label periods. The rate of initial onset and cumulative incidence of grade 3/4 TEAEs and serious TEAEs were similar for darolutamide and placebo groups over 24 months.

CONCLUSION

Extended treatment with darolutamide was well tolerated and no new safety signals were observed. Most ARi-associated and androgen-suppressive treatment-related TEAEs occurred at low incidences with darolutamide, were similar to placebo, and showed minimal increase over time with continued treatment.

TRIAL NUMBER

ClinicalTrials.gov identifier NCT02200614.

First-line talazoparib with enzalutamide in HRR-deficient metastatic castration-resistant prostate cancer: the phase 3 TALAPRO-2 trial

Preclinical evidence has suggested an interplay between the androgen receptor, which largely drives the growth of prostate cancer cells, and poly(ADP-ribose) polymerase. This association provides a rationale for their co-inhibition for the treatment of metastatic castration-resistant prostate cancer (mCRPC), an area of unmet medical need. The phase 3 TALAPRO-2 study investigated combining the poly(ADP-ribose) polymerase inhibitor talazoparib with enzalutamide versus enzalutamide alone as first-line treatment of mCRPC. Patients were prospectively assessed for tumor alterations in DNA damage response genes involved in homologous recombination repair (HRR). Two cohorts were enrolled sequentially: an all-comers cohort that was enrolled first (cohort 1; N = 805 (169 were HRR-deficient)), followed by an HRR-deficient-only cohort (cohort 2; N = 230). We present results from the alpha-controlled primary analysis for the combined HRR-deficient population (N = 399). Patients were randomized in a 1:1 ratio to talazoparib or placebo, plus enzalutamide. The primary endpoint, radiographic progression-free survival, was met (median not reached at the time of the analysis for the talazoparib group versus 13.8 months for the placebo group; hazard ratio, 0.45; 95% confidence interval, 0.33 to 0.61; P < 0.0001). Data for overall survival, a key secondary endpoint, are immature but favor talazoparib (hazard ratio, 0.69; 95% confidence interval, 0.46 to 1.03; P = 0.07). Common adverse events in the talazoparib group were anemia, fatigue and neutropenia. Combining talazoparib with enzalutamide significantly improved radiographic progression-free survival in patients with mCRPC harboring HRR gene alterations, supporting talazoparib plus enzalutamide as a potential first-line treatment for these patients. ClinicalTrials.gov Identifier: NCT03395197 .

US Clinical Practice Patterns of Intravesical Chemotherapy for Bacillus Calmette-Guérin-Unresponsive and Bacillus Calmette-Guérin-Exposed Nonmuscle-Invasive Bladder Cancer

INTRODUCTION

The goal of this survey was to evaluate the treatment and practice pattern of patients with high-grade papillary Ta, T1 nonmuscle-invasive bladder cancer (NMIBC), and carcinoma in situ (CIS) in bacillus Calmette-Guérin (BCG)-unresponsive (with adequate BCG exposure = adequate BCG) and those with less than adequate BCG exposure (BCG-exposed).

METHODS

An internet-based survey with a target duration of 5 minutes was sent to US urologists who manage patients with NMIBC. Respondents were recruited from the Sesen Bio target list based upon BCG utilization.

RESULTS

In 2022, 100 urologists who manage patients with papillary tumors and 159 urologists who manage patients with CIS tumors filled out the survey. Most (78%) were community-based urologists. Study respondents managed an average of 33 (range: 6-158) CIS patients and 44 (range: 10-200) high-grade patients with papillary disease (without CIS) over the past 6 months. Approximately 70% of physicians identified either gemcitabine (∼40%) or mitomycin C (∼30%) as the most often used intravesical chemotherapies for BCG unresponsive and BCG exposed groups. Most physicians reported the use of gemcitabine 2 g or mitomycin C 40 mg in a specific regimen for induction (once a week × 6 weeks) and maintenance (once a month × 12 months). Responses were consistent across groups of BCG therapy (adequate vs BCG-exposed). Physicians were slightly more likely to use a maintenance regimen for the adequate BCG patient.

CONCLUSIONS

The most common treatments received by patients with BCG-unresponsive and BCG-exposed NMIBC were intravesical chemotherapy (single-agent gemcitabine or mitomycin C), regardless of whether CIS or papillary disease was present.

Novel hormone therapy and coordination of care in high-risk biochemically recurrent prostate cancer

Biochemical recurrence (BCR) occurs in 20-50% of patients with prostate cancer (PCa) undergoing primary definitive treatment. Patients with high-risk BCR have an increased risk of metastatic progression and subsequent PCa-specific mortality, and thus could benefit from treatment intensification. Given the increasing complexity of diagnostic and therapeutic modalities, multidisciplinary care (MDC) can play a crucial role in the individualized management of this patient population. This review explores the role for MDC when evaluating the clinical evidence for the evolving definition of high-risk BCR and the emerging therapeutic strategies, especially with novel hormone therapies (NHTs), for patients with either high-risk BCR or oligometastatic PCa. Clinical studies have used different characteristics to define high-risk BCR and there is no consensus regarding the definition of high-risk BCR nor for management strategies. Next-generation imaging and multigene panels offer potential enhanced patient identification and precision-based decision-making, respectively. Treatment intensification with NHTs, either alone or combined with radiotherapy or metastasis-directed therapy, has been promising in clinical trials in patients with high-risk BCR or oligometastases. As novel risk-stratification and treatment options as well as evidence-based literature evolve, it is important to involve a multidisciplinary team to identify patients with high-risk features at an earlier stage, and make informed decisions on the treatments that could optimize their care and long-term outcomes. Nevertheless, MDC data are scarce in the BCR or oligometastatic setting. Efforts to integrate MDC into the standard management of this patient population are needed, and will likely improve outcomes across this heterogeneous PCa patient population.

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.

Enzalutamide and Quality of Life in Biochemically Recurrent Prostate Cancer

Enzalutamide and Quality of Life in Prostate CancerFreedland et al. present the health-related quality of life outcomes for patients with biochemically recurrent prostate cancer who were randomly assigned to enzalutamide plus leuprolide, enzalutamide monotherapy, or leuprolide alone (EMBARK trial). The key objectives were to determine differences in time to first and confirmed clinically meaningful deterioration in pain and time to first and confirmed clinically meaningful deterioration in functional status. There were no differences among the key outcomes among all three groups.

Pembrolizumab and Enzalutamide in Patients with Abiraterone Acetate-Pretreated Metastatic Castration-Resistant Prostate Cancer: Cohort C of the Phase 1b/2 KEYNOTE-365 Study

BACKGROUND

Limited responses have been observed in patients treated with enzalutamide after disease progression on abiraterone for metastatic castration-resistant prostate cancer (mCRPC), but androgen receptor signaling impacts T-cell function.

OBJECTIVE

To evaluate the efficacy and safety of pembrolizumab plus enzalutamide in mCRPC.

DESIGN, SETTING, AND PARTICIPANTS

Patients in cohort C of the phase 1b/2 KEYNOTE-365 study, who received ≥4 wk of treatment with abiraterone acetate in the prechemotherapy mCRPC state and experienced treatment failure or became drug-intolerant, were included.

INTERVENTION

Pembrolizumab 200 mg intravenously every 3 wk plus enzalutamide 160 mg orally once daily.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoints were safety, the confirmed prostate-specific antigen (PSA) response rate, and the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors version 1.1 on blinded independent central review (BICR). Secondary endpoints included radiographic progression-free survival (rPFS) on BICR and overall survival (OS).

RESULTS AND LIMITATIONS

A total of 102 patients received pembrolizumab plus enzalutamide. Median follow-up was 51 mo (interquartile range 37-56). The confirmed PSA response rate was 24% (95% confidence interval [CI] 16-33%). The confirmed ORR was 11% (95% CI 2.9-25%; 4/38 patients; two complete responses). Median rPFS was 6.0 mo (95% CI 4.1-6.3). Median OS was 20 mo (95% CI 17-24). Treatment-related adverse events (TRAEs) occurred in 94 patients (92%); grade 3-5 TRAEs occurred in 44 patients (43%). The incidence of treatment-related rash was higher with combination therapy than expected from the safety profile of each drug. One patient (1.0%) died of a TRAE (cause unknown). Study limitations include the single-arm design.

CONCLUSIONS

Pembrolizumab plus enzalutamide had limited antitumor activity in patients who received prior abiraterone treatment without previous chemotherapy for mCRPC, with a safety profile consistent with the individual profiles of each agent.

PATIENT SUMMARY

Pembrolizumab plus enzalutamide showed limited antitumor activity and manageable safety in patients with metastatic castration-resistant prostate cancer. The KEYNOTE-365 trial is registered on ClinicalTrials.gov as NCT02861573.

Development and evaluation of the MiCheck® Prostate test for clinically significant prostate cancer

BACKGROUND

There is a clinical need to identify patients with an elevated PSA who would benefit from prostate biopsy due to the presence of clinically significant prostate cancer (CSCaP). We have previously reported the development of the MiCheck® Test for clinically significant prostate cancer. Here, we report MiCheck's further development and incorporation of the Roche Cobas standard clinical chemistry analyzer.

OBJECTIVES

To further develop and adapt the MiCheck® Prostate test so it can be performed using a standard clinical chemistry analyzer and characterize its performance using the MiCheck-01 clinical trial sample set.

DESIGN, SETTINGS, AND PARTICIPANTS

About 358 patient samples from the MiCheck-01 US clinical trial were used for the development of the MiCheck® Prostate test. These consisted of 46 controls, 137 non-CaP, 62 non-CSCaP, and 113 CSCaP.

METHODS

Serum analyte concentrations for cellular growth factors were determined using custom-made Luminex-based R&D Systems multi-analyte kits. Analytes that can also be measured using standard chemistry analyzers were examined for their ability to contribute to an algorithm with high sensitivity for the detection of clinically significant prostate cancer. Samples were then re-measured using a Roche Cobas analyzer for development of the final algorithm.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Logistic regression modeling with Monte Carlo cross-validation was used to identify Human Epidydimal Protein 4 (HE4) as an analyte able to significantly improve the algorithm specificity at 95% sensitivity. A final model was developed using analyte measurements from the Cobas analzyer.

RESULTS

The MiCheck® logistic regression model was developed and consisted of PSA, %free PSA, DRE, and HE4. The model differentiated clinically significant cancer from no cancer or not-clinically significant cancer with AUC of 0.85, sensitivity of 95%, and specificity of 50%. Applying the MiCheck® test to all evaluable 358 patients from the MiCheck-01 study demonstrated that up to 50% of unnecessary biopsies could be avoided while delaying diagnosis of only 5.3% of Gleason Score (GS) ≥3+4 cancers, 1.8% of GS≥4+3 cancers and no cancers of GS 8 to 10.

CONCLUSIONS

The MiCheck® Prostate test identifies clinically significant prostate cancer with high sensitivity and negative predictive value (NPV). It can be performed in a clinical laboratory using a Roche Cobas clinical chemistry analyzer. The MiCheck® Prostate test could assist in reducing unnecessary prostate biopsies with a marginal number of patients experiencing a delayed diagnosis.

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 .

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.).

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.

Efficacy and safety outcomes of darolutamide in patients with non-metastatic castration-resistant prostate cancer with comorbidities and concomitant medications from the randomised phase 3 ARAMIS trial

PURPOSE

In patients with non-metastatic castration-resistant prostate cancer (nmCRPC) in the Androgen Receptor Antagonizing Agent for Metastasis-free Survival (ARAMIS) trial, darolutamide significantly improved median metastasis-free survival by nearly 2 years and reduced the risk of death by 31% versus placebo, with a favourable safety/tolerability profile. This post hoc analysis of ARAMIS evaluated efficacy and safety in patients by number of comorbidities and concomitant medications.

METHODS

Patients with nmCRPC were randomised 2:1 to darolutamide (n = 955) or placebo (n = 554) while continuing androgen-deprivation therapy. Overall survival (OS) and treatment-emergent adverse events (TEAEs) were evaluated in subgroups by median numbers of ongoing comorbidities and concomitant medications. HRs were determined from univariate analysis using Cox regression.

FINDINGS

Median numbers of comorbidities and concomitant medications were 6 and 10, respectively, with 41.6% of patients having >6 comorbidities and 48.8% taking >10 concomitant medications. For patients with ≤ 6 and >6 comorbidities, darolutamide increased OS versus placebo (hazard ratio [HR] 0.65 and 0.73, respectively), and this benefit was consistent for cardiovascular, metabolic, and other comorbidities (HR range: 0.39-0.88). For patients taking ≤ 10 and >10 concomitant medications, increased OS was also observed with darolutamide versus placebo (HR 0.76 and 0.66, respectively), and the benefit was consistent across medication classes (HR range: 0.45-0.80). Incidences of TEAEs and TEAEs leading to treatment discontinuation with darolutamide were similar to placebo across subgroups by numbers of comorbidities and concomitant medications.

CONCLUSIONS

The OS benefit and safety of darolutamide remained consistent with that observed in the overall ARAMIS population, even in patients with high numbers of comorbidities or concomitant medications.

CLINICALTRIALS

GOV REGISTRATION

NCT02200614.

TWEETABLE ABSTRACT

Darolutamide increased overall survival versus placebo, and incidences of most adverse events were similar between treatments in patients with ≤ 6 or >6 comorbidities and those taking ≤ 10 or >10 concomitant medications.

Treatment of Low-grade Intermediate-risk Nonmuscle-invasive Bladder Cancer With UGN-102 ± Transurethral Resection of Bladder Tumor Compared to Transurethral Resection of Bladder Tumor Monotherapy: A Randomized, Controlled, Phase 3 Trial (ATLAS)

PURPOSE

Low-grade intermediate-risk nonmuscle-invasive bladder cancer is a chronic illness commonly treated by repetitive transurethral resection of bladder tumor. We compared the efficacy and safety of intravesical chemoablation with UGN-102 (a reverse thermal gel containing mitomycin), with or without subsequent transurethral resection of bladder tumor, to transurethral resection of bladder tumor alone in patients with low-grade intermediate-risk nonmuscle-invasive bladder cancer.

MATERIALS AND METHODS

This prospective, randomized, phase 3 trial recruited patients with new or recurrent low-grade intermediate-risk nonmuscle-invasive bladder cancer to receive initial treatment with either UGN-102 once weekly for 6 weeks or transurethral resection of bladder tumor. Patients were followed quarterly by endoscopy, cytology, and for-cause biopsy. The primary end point was disease-free survival. All patients were followed for adverse events.

RESULTS

Trial enrollment was halted by the sponsor to pursue an alternative development strategy after 282 of a planned 632 patients were randomized to UGN-102 ± subsequent transurethral resection of bladder tumor (n=142) or transurethral resection of bladder tumor monotherapy (n=140), rendering the trial underpowered to perform hypothesis testing. Patients were predominantly male and ≥65 years of age. Tumor-free complete response 3 months after initial treatment was achieved by 92 patients (65%) who received UGN-102 and 89 patients (64%) treated by transurethral resection of bladder tumor. The estimated probability of disease-free survival 15 months after randomization was 72% for UGN-102 ± transurethral resection of bladder tumor and 50% for transurethral resection of bladder tumor (hazard ratio 0.45). The most common adverse events (incidence ≥10%) in the UGN-102 group were dysuria, micturition urgency, nocturia, and pollakiuria.

CONCLUSIONS

Primary, nonsurgical chemoablation with UGN-102 for the management of low-grade intermediate-risk nonmuscle-invasive bladder cancer offers a potential therapeutic alternative to immediate transurethral resection of bladder tumor monotherapy and warrants further investigation.

Cardiovascular Effects of GnRH Antagonists Compared With Agonists in Prostate Cancer: A Systematic Review

Background

Androgen deprivation therapy is the cornerstone of treatment for patients with advanced prostate cancer. Meta-analysis of small, oncology-focused trials suggest gonadotropin-releasing hormone (GnRH) antagonists may be associated with fewer adverse cardiovascular outcomes compared with GnRH agonists.

Objectives

This study sought to determine whether GnRH antagonists were associated with fewer major adverse cardiovascular events compared with GnRH agonists.

Methods

Electronic databases were searched for all prospective, randomized trials comparing GnRH antagonists with agonists. The primary outcome was a major adverse cardiovascular event as defined by the following standardized Medical Dictionary for Regulatory Activities terms: "myocardial infarction," "central nervous system hemorrhages and cerebrovascular conditions," and all-cause mortality. Bayesian meta-analysis models with random effects were fitted.

Results

A total of 11 eligible studies of a maximum duration of 3 to 36 months (median = 12 months) enrolling 4,248 participants were included. Only 1 trial used a blinded, adjudicated event process, whereas potential bias persisted in all trials given their open-label design. A total of 152 patients with primary outcome events were observed, 76 of 2,655 (2.9%) in GnRH antagonist-treated participants and 76 of 1,593 (4.8%) in agonist-treated individuals. Compared with GnRH agonists, the pooled OR of GnRH antagonists for the primary endpoint was 0.57 (95% credible interval: 0.37-0.86) and 0.58 (95% credible interval: 0.32-1.08) for all-cause death.

Conclusions

Despite the addition of the largest, dedicated cardiovascular outcome trial, the volume and quality of available data to definitively answer this question remain suboptimal. Notwithstanding these limitations, the available data suggest that GnRH antagonists are associated with fewer cardiovascular events, and possibly mortality, compared with GnRH agonists.

Biochemical recurrence in patients with prostate cancer after primary definitive therapy: treatment based on risk stratification

BACKGROUND

Nearly one-third of patients with prostate cancer (PCa) experience biochemical recurrence (BCR) after primary definitive treatment. BCR increases the risk of distant metastasis and mortality in patients with prognostically unfavorable features. These patients are best managed with a tailored treatment strategy incorporating risk stratification using clinicopathological factors, next-generation imaging, and genomic testing.

OBJECTIVE

This narrative review examines the utility of risk stratification for the management of patients with BCR in the context of clinical trial data, referencing the latest recommendations by European and US medical societies.

METHODS

PubMed was searched for relevant studies published through May 21 2023 on treatment of patients with BCR after radical prostatectomy (RP) or external beam radiotherapy (EBRT).

RESULTS

European and US guidelines support the risk-stratified management of BCR. Post-RP, salvage EBRT (with or without androgen deprivation therapy [ADT]) is an accepted treatment option for patients with BCR. Post-EBRT, local salvage therapies (RP, cryotherapy, high-intensity focused ultrasound, stereotactic body radiotherapy, and low-dose-rate and high-dose-rate brachytherapy) have demonstrated comparable relapse-free survival rates but differing adverse event profiles, short and long term. Local salvage therapies should be used for local-only relapses while ADT should be considered for regional or distant relapses. In practice, patients often receive ADT, with varying guidance for intermittent ADT vs. continuous ADT, due to consideration of quality-of-life effects.

CONCLUSIONS

Despite a lack of consensus for BCR treatment among guideline associations and medical societies, risk stratification of patients is essential for personalized treatment approaches, as it allows for an informed selection of therapeutic strategies and estimation of adverse events. In lower-risk disease, observation is recommended while in higher-risk disease, after failed repeat local therapy, ADT and/or clinical trial enrollment may be appropriate. Results from ongoing clinical studies of patients with BCR should provide consensus for management.

Application of next-generation imaging in biochemically recurrent prostate cancer

BACKGROUND

Biochemical recurrence (BCR) following primary interventional treatment occurs in approximately one-third of patients with prostate cancer (PCa). Next-generation imaging (NGI) can identify local and metastatic recurrence with greater sensitivity than conventional imaging, potentially allowing for more effective interventions. This narrative review examines the current clinical evidence on the utility of NGI for patients with BCR.

METHODS

A search of PubMed was conducted to identify relevant publications on NGI applied to BCR. Given other relevant recent reviews on the topic, this review focused on papers published between January 2018 to May 2023.

RESULTS

NGI technologies, including positron emission tomography (PET) radiotracers and multiparametric magnetic resonance imaging, have demonstrated increased sensitivity and selectivity for diagnosing BCR at prostate-specific antigen (PSA) concentrations <2.0 ng/ml. Detection rates range between 46% and 50%, with decreasing PSA levels for choline (1-3 ng/ml), fluciclovine (0.5-1 ng/ml), and prostate-specific membrane antigen (0.2-0.49 ng/ml) PET radiotracers. Expert working groups and European and US medical societies recommend NGI for patients with BCR.

CONCLUSIONS

Available data support the improved detection performance and selectivity of NGI modalities versus conventional imaging techniques; however, limited clinical evidence exists demonstrating the application of NGI to treatment decision-making and its impact on patient outcomes. The emergence of NGI and displacement of conventional imaging may require a reexamination of the current definitions of BCR, altering our understanding of early recurrence. Redefining the BCR disease state by formalizing the role of NGI in patient management decisions will facilitate greater alignment across research efforts and better reflect the published literature.

Plain language summary: Can declines in prostate-specific antigen level indicate how long patients with advanced prostate cancer will live when treated with enzalutamide?

WHAT IS THIS SUMMARY ABOUT?

This is a summary of a research article originally published in the Journal of Urology. The PROSPER study involved men who had a type of advanced prostate cancer called non-metastatic castration-resistant prostate cancer (nmCRPC). In patients with nmCRPC, their prostate cancer keeps growing even after traditional hormone treatments. In these patients, rising prostate-specific antigen (PSA) levels suggest that cancer is active but CT and bone scans show that it has not spread to other parts of the body. Everyone in this study received androgen deprivation therapy (ADT) either with the medicine enzalutamide or a placebo. Enzalutamide is a medicine that can slow or stop androgens, such as testosterone, from making prostate cancer grow. The main results of the PROSPER study showed that patients with nmCRPC treated with enzalutamide and ADT lived longer than patients treated with placebo and ADT. In this study, researchers wanted to know if the findings were different depending on how much patients' PSA level declined after enzalutamide treatment. Researchers also wanted to know if this made a difference in how long patients lived without the cancer spreading to other parts of their body.

WHAT WERE THE RESULTS?

Researchers found that patients with a large decline in PSA level after treatment were more likely to live longer and without their cancer spreading.

WHAT DO THE RESULTS MEAN?

This study shows a link between PSA level changes and how long patients with nmCRPC live when treated with enzalutamide and ADT. These results may help health professionals monitor patients with different PSA level changes after enzalutamide treatment. Patients with a large decline in PSA level may not need to be monitored as closely as patients with a small decline in PSA level.

The Efficacy of Enzalutamide plus Androgen Deprivation Therapy in Oligometastatic Hormone-sensitive Prostate Cancer: A Post Hoc Analysis of ARCHES

BACKGROUND

Few phase 3 studies have evaluated optimal systemic treatment strategies for patients with oligometastatic hormone-sensitive prostate cancer (HSPC), who may be at risk of undertreatment.

OBJECTIVE

To evaluate outcomes for patients with oligometastatic and polymetastatic HSPC treated with enzalutamide plus androgen deprivation therapy (ADT) versus placebo plus ADT.

DESIGN, SETTING, AND PARTICIPANTS

This was a post hoc analysis of data for 927 patients with nonvisceral metastatic HSPC in the ARCHES trial (NCT02677896).

INTERVENTION

Patients were randomized 1:1 to enzalutamide (160 mg/d orally) plus ADT or placebo plus ADT with HSPC categorized as oligometastatic (1-5 metastases) or polymetastatic (≥6 metastases).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The treatment effect on radiographic progression-free survival (rPFS), overall survival (OS), and secondary efficacy endpoints was evaluated in terms of the number of metastases. Safety was assessed. Cox proportional hazards models were used to generate hazard ratios (HRs). The Brookmeyer and Crowley method was used to generate 95% confidence intervals (CIs) for Kaplan-Meier median values.

RESULTS AND LIMITATIONS

Enzalutamide plus ADT improved rPFS (HR 0.27, 95% CI 0.16-0.46; p < 0.001), OS (HR 0.59, 95% CI 0.40-0.87; p < 0.005), and secondary endpoints in patients with oligometastatic or polymetastatic disease (rPFS: HR 0.33, 95% CI 0.23-0.46; p < 0.001; OS: HR 0.55, 95% CI 0.41-0.74; p < 0.001). Safety profiles were generally similar across subgroups. Limitations include the small numbers of patients with fewer than three metastases.

CONCLUSIONS

This post hoc analysis demonstrated the utility of enzalutamide, irrespective of metastatic burden or type of oligometastatic disease, and suggests that earlier treatment intensification with systemic potent androgen receptor inhibition is advantageous.

PATIENT SUMMARY

This study considered two treatment options for metastatic hormone-sensitive prostate cancer in patients with one to five metastases or six or more metastases. Treatment with enzalutamide plus ADT improved survival and other outcomes over ADT alone, whether patients had few or many metastases.

Talazoparib plus enzalutamide in men with first-line metastatic castration-resistant prostate cancer (TALAPRO-2): a randomised, placebo-controlled, phase 3 trial

BACKGROUND

Co-inhibition of poly(ADP-ribose) polymerase (PARP) and androgen receptor activity might result in antitumour efficacy irrespective of alterations in DNA damage repair genes involved in homologous recombination repair (HRR). We aimed to compare the efficacy and safety of talazoparib (a PARP inhibitor) plus enzalutamide (an androgen receptor blocker) versus enzalutamide alone in patients with metastatic castration-resistant prostate cancer (mCRPC).

METHODS

TALAPRO-2 is a randomised, double-blind, phase 3 trial of talazoparib plus enzalutamide versus placebo plus enzalutamide as first-line therapy in men (age ≥18 years [≥20 years in Japan]) with asymptomatic or mildly symptomatic mCRPC receiving ongoing androgen deprivation therapy. Patients were enrolled from 223 hospitals, cancer centres, and medical centres in 26 countries in North America, Europe, Israel, South America, South Africa, and the Asia-Pacific region. Patients were prospectively assessed for HRR gene alterations in tumour tissue and randomly assigned (1:1) to talazoparib 0·5 mg or placebo, plus enzalutamide 160 mg, administered orally once daily. Randomisation was stratified by HRR gene alteration status (deficient vs non-deficient or unknown) and previous treatment with life-prolonging therapy (docetaxel or abiraterone, or both: yes vs no) in the castration-sensitive setting. The sponsor, patients, and investigators were masked to talazoparib or placebo, while enzalutamide was open-label. The primary endpoint was radiographic progression-free survival (rPFS) by blinded independent central review, evaluated in the intention-to-treat population. Safety was evaluated in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (NCT03395197) and is ongoing.

FINDINGS

Between Jan 7, 2019, and Sept 17, 2020, 805 patients were enrolled and randomly assigned (402 to the talazoparib group and 403 to the placebo group). Median follow-up for rPFS was 24·9 months (IQR 21·9-30·2) for the talazoparib group and 24·6 months (14·4-30·2) for the placebo group. At the planned primary analysis, median rPFS was not reached (95% CI 27·5 months-not reached) for talazoparib plus enzalutamide and 21·9 months (16·6-25·1) for placebo plus enzalutamide (hazard ratio 0·63; 95% CI 0·51-0·78; p<0·0001). In the talazoparib group, the most common treatment-emergent adverse events were anaemia, neutropenia, and fatigue; the most common grade 3-4 event was anaemia (185 [46%] of 398 patients), which improved after dose reduction, and only 33 (8%) of 398 patients discontinued talazoparib due to anaemia. Treatment-related deaths occurred in no patients in the talazoparib group and two patients (<1%) in the placebo group.

INTERPRETATION

Talazoparib plus enzalutamide resulted in clinically meaningful and statistically significant improvement in rPFS versus standard of care enzalutamide as first-line treatment for patients with mCRPC. Final overall survival data and additional long-term safety follow-up will further clarify the clinical benefit of the treatment combination in patients with and without tumour HRR gene alterations.

FUNDING

Pfizer.

Combination Treatment with Sipuleucel-T and Abiraterone Acetate or Enzalutamide for Metastatic Castration-Resistant Prostate Cancer: STAMP and STRIDE Trials

PURPOSE

We present long-term outcomes from 2 randomized studies [STAMP (with abiraterone, NCT01487863) and STRIDE (with enzalutamide, NCT01981122)] that were performed to study the impact of sequential or concurrent administration of androgen receptor-targeting agents (ARTAs) on sipuleucel-T immune response and overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC).

PATIENTS AND METHODS

Sipuleucel-T was administered per current prescribing information. Results from STRIDE are presented together with updated STAMP results. Survival status of patients was updated using demographic information to query the National Death Index (NDI). Kaplan-Meier methodology was used to analyze survival.

RESULTS

Updated data reduced patient censoring in each study compared with the original analyses; the 95% confidence intervals (CIs) for OS are now estimable. Updated median OS (95% CI) is 33.3 (24.1-40.7) months for STAMP and 32.5 (26.0-45.1) months for STRIDE. There was no notable impact on median OS [HR, 0.727 (0.458-1.155); P = 0.177, reference = STRIDE]. OS with sequential administration was similar to concurrent administration [NDI update: HR, 0.963 (0.639-1.453); P = 0.845, reference = concurrent arm]. Sipuleucel-T potency, measured as antigen-presenting cell (APC) activation, was higher in subsequent infusions compared with the first infusion. Humoral responses (IgG + IgM antibody titers) to PA2024 and prostatic acid phosphatase were significantly elevated versus baseline. No new safety signals were observed.

CONCLUSIONS

Median OS was consistent regardless of whether the agents were administered sequentially or concurrently, including after NDI update. Results suggest that sipuleucel-T induces an immunologic prime-boost effect after initial sipuleucel-T exposure, even when combined with ARTAs.

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.

Clinical outcomes and treatment patterns in REASSURE: planned interim analysis of a real-world observational study of radium-223 in metastatic castration-resistant prostate cancer

Background

Radium-223, a targeted alpha therapy, is approved to treat bone-dominant metastatic castration-resistant prostate cancer (mCRPC), based on significantly prolonged overall survival versus placebo and a favourable safety profile in the phase 3 ALSYMPCA study. ALSYMPCA was conducted when few other treatment options were available, and prospectively collected data are limited on the use of radium-223 in the current mCRPC treatment landscape. We sought to understand long-term safety and treatment patterns in men who received radium-223 in real-world clinical practice.

Methods

REASSURE (NCT02141438) is a global, prospective, observational study of radium-223 in men with mCRPC. Primary outcomes are adverse events (AEs), including treatment-emergent serious AEs (SAEs) and drug-related AEs during and ≤30 days after radium-223 completion, grade 3/4 haematological toxicities ≤6 months after last radium-223 dose, drug-related SAEs after radium-223 therapy completion, and second primary malignancies.

Findings

Data collection commenced on Aug 20, 2014, and the data cutoff date for this prespecified interim analysis was Mar 20, 2019 (median follow-up 11.5 months [interquartile range 6.0-18.6]), 1465 patients were evaluable. For second primary malignancies, 1470 patients were evaluable, 21 (1%) of whom had a total of 23 events. During radium-223 therapy, 311 (21%) of 1465 patients had treatment-emergent SAEs, and 510 (35%) had drug-related AEs. In the 6 months after completion of radium-223 therapy, 214 (15%) patients had grade 3/4 haematological toxicities. Eighty patients (5%) had post-treatment drug-related SAEs. Median overall survival was 15.6 months (95% confidence interval 14.6-16.5) from radium-223 initiation. Patient-reported pain scores declined or stabilised. Seventy (5%) patients had fractures.

Interpretation

REASSURE offers insight into radium-223 use in global real-world clinical practice with currently available therapies. At this interim analysis, with a median follow-up of almost 1 year, 1% of patients had second primary malignancies, and safety and overall survival findings were consistent with clinical trial experience. Final analysis of REASSURE is due in 2024.

Funding

Bayer HealthCare.

Impact of darolutamide on local symptoms: pre-planned and post hoc analyses of the ARAMIS trial

OBJECTIVE

To assess, the effect of darolutamide (a structurally distinct androgen receptor inhibitor) on urinary and bowel symptoms, using data from the phase III ARAMIS trial (NCT02200614) that showed darolutamide significantly reduced the risk of metastasis and death versus placebo.

PATIENTS AND METHODS

Patients with non-metastatic castration-resistant prostate cancer (nmCRPC) were randomised 2:1 to darolutamide (n = 955) or placebo (n = 554). Local symptom control was assessed by first prostate cancer-related invasive procedures and post hoc analyses of time to deterioration in quality of life (QoL) using total urinary and bowel symptoms, and individual questions for these symptoms from the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Prostate Cancer Module subscales and Functional Assessment of Cancer Therapy-Prostate prostate cancer subscale. Prostate-specific antigen (PSA) responses were correlated with urinary and bowel adverse events (AEs).

RESULTS

Fewer patients receiving darolutamide (4.7%) versus placebo (9.6%) underwent invasive procedures, and time to first procedure was prolonged with darolutamide (hazard ratio 0.42, 95% confidence interval 0.28-0.62). Darolutamide significantly (P < 0.01) delayed worsening of QoL for total urinary and bowel symptoms versus placebo, mostly attributed by individual symptoms of urinary frequency, associated pain, and interference with daily activities. AEs of urinary retention and dysuria were less frequent with darolutamide, and greater PSA response (≥90%, ≥50% and <90%, <50%) among darolutamide-treated patients was associated with lower incidences of urinary retention (2.2%, 4.2%, 5.1%) and dysuria (0.5%, 3.2%, 5.1%), respectively.

CONCLUSIONS

Darolutamide demonstrated a positive impact on local disease recurrence and symptom control in patients with nmCRPC, delayed time to deterioration in QoL related to urinary and bowel symptoms, and a favourable safety profile showing similar incidence of urinary- and bowel-related AEs compared with placebo.

Efficacy and Safety of Darolutamide in Patients with Nonmetastatic Castration-resistant Prostate Cancer Stratified by Prostate-specific Antigen Doubling Time: Planned Subgroup Analysis of the Phase 3 ARAMIS Trial

BACKGROUND

Patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) have a high risk of progression to metastatic disease, particularly if their prostate-specific antigen doubling time (PSADT) is ≤6 mo. However, patients remain at a high risk with a PSADT of >6 mo.

OBJECTIVE

To evaluate the efficacy and safety of darolutamide versus placebo in patients stratified by PSADT >6 or ≤6 mo.

DESIGN, SETTING, AND PARTICIPANTS

A planned subgroup analysis of a global multicenter, double-blind, randomized, phase 3 trial in men with nmCRPC and PSADT ≤10 mo was conducted.

INTERVENTION

Patients were randomized 2:1 to oral darolutamide 600 mg twice daily or placebo, while continuing androgen-deprivation therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was metastasis-free survival (MFS). Secondary endpoints were overall survival (OS) and times to pain progression, first cytotoxic chemotherapy, and symptomatic skeletal events. Quality of life (QoL) was measured using validated prostate-relevant tools. Safety was recorded throughout the study.

RESULTS AND LIMITATIONS

Of 1509 patients enrolled, 469 had PSADT >6 mo (darolutamide n = 286; placebo n = 183) and 1040 had PSADT ≤6 mo (darolutamide n = 669; placebo n = 371). Baseline characteristics were balanced between subgroups. Darolutamide significantly prolonged MFS versus placebo in both subgroups (unstratified hazard ratio [95% confidence interval]: PSADT >6 mo, 0.38 [0.26-0.55]; PSADT ≤6 mo, 0.41 [0.33-0.52]). OS and other efficacy and QoL endpoints favored darolutamide with significant improvement over placebo in both subgroups. The incidence of adverse events, including events commonly associated with androgen receptor inhibitors (fractures, falls, hypertension, and mental impairment), and discontinuations due to adverse events were low and similar to placebo. Limitations include small subgroup populations.

CONCLUSIONS

In patients with nmCRPC and PSADT >6 mo (maximum 10 mo), darolutamide provided a favorable benefit/risk ratio, characterized by significant improvements in MFS, OS, and other clinically relevant endpoints; maintenance of QoL; and favorable tolerability.

PATIENT SUMMARY

In patients with prostate cancer that has stopped responding to standard hormonal therapy (indicated by an increase in prostate-specific antigen [PSA] levels), there is a risk that the cancer will spread to other parts of the body. This risk is highest when the time it takes for the PSA level to double (ie, "PSA doubling time" [PSADT]) is less than 6 mo. However, there is still a risk that the cancer will spread even if the PSADT is longer than 6 mo. In a group of patients whose PSADT was more than 6 mo but no more than 10 mo, treatment with darolutamide slowed the cancer spread and allowed them to live longer than patients who received placebo (inactive drug). Darolutamide treatment did not cause many side effects and helped maintain patients' quality of life without disruptions.

Real-world clinical outcomes of patients with localized prostate cancer (LPC) treated with external beam radiation therapy (EBRT)

330

Background: Patients (pts) with localized prostate cancer (LPC) or locally advanced prostate cancer (PC) have several treatment options, including external beam radiation therapy (EBRT) and radical prostatectomy, which can be curative in some pts. However, limited real-world evidence exists on the long-term clinical outcomes of these pts, particularly those with high-risk LPC (HRLPC). This study examines real-world clinical outcomes for HRLPC and low/intermediate risk LPC (LIRLPC) pts treated with EBRT in the US. Methods: A retrospective study using Surveillance, Epidemiology, and End Results (SEER)-Medicare linked registry-claims data from 2012−2019 included LPC pts aged ≥65 treated with EBRT as initial definitive therapy. Baseline demographic and clinical characteristics were summarized for HRLPC and LIRLPC pts. Clinical outcomes of interest (overall survival, metastasis-free survival [MFS] and time to initiation of advanced PC treatment) were compared using Kaplan-Meier (KM) and Cox proportional hazards (PH) models. Results: Of 11,127 LPC pts treated with EBRT within 6 months of LPC diagnosis, ~40% (n=4,414) were HRLPC and ~60% (N=6,713) were LIRLPC. Patient characteristics for both groups appeared similar, with mean age at EBRT initiation >70 years, 86% white, and mean follow-up time >40 months. ADT was used with EBRT in 78% HRLPC and 34% LIRLPC. Median (IQR) duration of ADT therapy (via KM analysis) was 9.9 (5.8, 21.5) months for HRLPC and 7.2 (5.3, 9.8) months for LIRLPC. A higher proportion of HRLPC vs LIRLPC pts experienced metastasis, death, and progression to advanced PC therapies (medians were not reached). Unadjusted Cox PH survival analyses showed higher risk of mortality, metastasis, and advanced PC therapy use for HRLPC vs LIRLPC pts. Conclusions: This real-world study of clinical outcomes in pts with HRLPC and LIRLPC treated with EBRT suggested substantial additional disease burden in pts with HRLPC and highlights the need for additional strategies and treatments to improve clinical outcomes in pts with HRLPC. [Table: see text]

Pembrolizumab (pembro) monotherapy for patients (pts) with high-risk non–muscle-invasive bladder cancer (HR NMIBC) unresponsive to bacillus Calmette–Guérin (BCG): Results from cohort B of the phase 2 KEYNOTE-057 trial

LBA442

Background: Although most pts with HR NMIBC respond to BCG, pts whose cancer does not respond or who relapse within 12 mo have poor prognosis and require radical cystectomy (RC). The single-arm, multicohort phase 2 KEYNOTE-057 trial (NCT02625961) was designed to investigate the safety and efficacy of pembro monotherapy for pts with BCG-unresponsive HR NMIBC (per FDA) who were ineligible or declined to undergo RC. Results from cohort A (carcinoma in situ [CIS] ± papillary tumors) showed a clinical complete response rate of 41% at 3 mo and led to approval of pembro monotherapy for such pts in the United States. We describe the results from cohort B (papillary tumors without CIS). Methods: Pts were aged ≥18 y with BCG-unresponsive HR NMIBC with papillary tumors only (high-grade Ta or any-grade T1) at baseline and ECOG PS 0-2. Pts received pembro 200 mg every 3 wk (Q3W) for ≤35 cycles (~2 y). Cancer was assessed at 12 wk and Q12W thereafter if no recurrent HR NMIBC or progression was observed; CT urography was done Q24W. Primary end points for cohort B were 12-mo disease-free survival (DFS) rate of HR NMIBC as assessed by central pathology/radiology review and safety, assuming a 12-mo DFS of >20% for HR NMIBC. Secondary efficacy end points were 12-mo DFS rate of any disease; progression-free survival (PFS) to worsening of grade, stage, or death; PFS to muscle invasion, metastasis, or death; and overall survival (OS). Results: Overall, 132 pts received pembro for a median of 9.5 cycles (range, 1.0-35.0). Median age was 72 y (range, 37-87); 57 pts (43.2%) had T1 stage; all pts (100%) had urothelial histology; 104 pts (78.8%) were male; pts received a median of 10 (range, 6-33) prior BCG instillations. Median follow-up was 45.4 mo (range, 14.9-77.1). Efficacy data are shown in Table. Thirty-one pts (23.5%) had RC after stopping pembro. Treatment-related AEs occurred in 97 pts (73.5%); 19 (14.4%) had a grade 3/4 treatment-related AE and 14 pts (10.6%) discontinued due to a treatment-related AE. No deaths from treatment-related AEs occurred. Conclusions: Pembro showed notable antitumor activity in pts with BCG-unresponsive non-CIS papillary HR NMIBC after ~45 mo of follow-up. Toxicity was manageable and consistent with that in cohort A, with no new safety signals. Results suggest pts with non-CIS papillary HR NMIBC unresponsive to BCG who declined or were ineligible to undergo RC may also benefit from pembro monotherapy. Clinical trial information: NCT02625961 . [Table: see text]

Efficacy and safety of darolutamide (DARO) in combination with androgen-deprivation therapy (ADT) and docetaxel (DOC) by disease volume and disease risk in the phase 3 ARASENS study

15

Background: In ARASENS (NCT02799602), DARO plus ADT and DOC significantly reduced the risk of death by 32.5% (HR 0.68; 95% CI: 0.57–0.80; P<0.0001) vs placebo (PBO) + ADT + DOC in patients (pts) with metastatic hormone-sensitive prostate cancer (mHSPC), with similar overall incidences of treatment-emergent adverse events (TEAEs) between groups. The effect of DARO on overall survival (OS) was consistent across prespecified subgroups, including de novo and recurrent disease. For pts with mHSPC, outcomes based on disease volume and risk provide additional information to clinicians. Methods: Pts with mHSPC were randomized 1:1 to DARO 600 mg twice daily or PBO, with ADT + DOC. High-volume disease was defined as visceral metastases and/or ≥4 bone metastases with ≥1 beyond the vertebral column/pelvis (CHAARTED criteria). High-risk disease was defined as ≥2 risk factors: Gleason score ≥8, ≥3 bone lesions, and presence of measurable visceral metastasis (LATITUDE criteria). OS for these subgroups was assessed using an unstratified Cox regression model. Results: Of 1305 pts in the full analysis set, 1005 (77%) had high-volume disease, 912 (70%) had high-risk disease, 300 (23%) had low-volume disease, and 393 (30%) had low-risk disease. DARO + ADT + DOC prolonged OS regardless of high- or low-volume disease with HRs of 0.69 and 0.68 vs PBO + DOC + ADT, respectively. OS benefit of DARO vs PBO was also similar for pts with high- or low-risk disease. DARO improved clinically relevant secondary endpoints vs PBO in high/low-volume and risk subgroups, with HRs generally in the range of those observed in the overall population. Incidences of TEAEs were consistent with the overall ARASENS population across subgroups by high/low volume and high/low risk. Conclusions: In pts with mHSPC, the benefits of early treatment intensification with DARO + ADT + DOC on OS and key pt-relevant secondary efficacy endpoints vs PBO + ADT + DOC were similar in patients with high- and low-volume as well as high- and low-risk mH+SPC. The favorable safety profile of DARO was reconfirmed in high/low-volume and high/low-risk populations. DARO + ADT + DOC sets a new standard of care for pts with mHSPC. Clinical trial information: NCT02799602 . [Table: see text]

A multi-center, open-label, randomized dose expansion study of PF-06821497, a potent and selective inhibitor of enhancer of zeste homolog 2 (EZH2), in patients with metastatic castration-resistant prostate cancer (mCRPC)

TPS282

Background: Enhancer of zeste homolog 2 (EZH2) encodes the histone methyltransferase component of the polycomb repressive complex-2, inducing transcriptional silencing of target genes, and is altered in cancers such as follicular lymphoma (FL), small cell lung cancer (SCLC), and metastatic castration-resistant prostate cancer (mCRPC). We evaluated the pharmacokinetics (PK), safety, and antitumor activity of PF-06821497, a potent and selective inhibitor of EZH2, in an ongoing phase I trial (NCT03460977 ) in patients (pts) with SCLC, CRPC, and FL as monotherapy and in combination with standard of care therapies. For pts with CRPC, the PF-06821497 recommended dose for expansion (RDE) is 1250 mg BID, in combination with enzalutamide plus androgen deprivation therapy (E). Part 2B of this trial further explores outcomes for pts dosed with PF-06821497 and E compared with E monotherapy. Methods: Part 2B compares the safety and efficacy of twice-daily PF-06821497 in combination with E (160 mg daily) (treatment arm) versus E monotherapy (control arm) administered continuously in patients with mCRPC previously treated with abiraterone. At trial entry, all pts will have evidence of prostate cancer progression per the modified Prostate Cancer Working Group 3 Criteria. Prior treatment with E is not allowed. Approximately 80 participants will be randomized in a 1:1 fashion into two arms, in US, Spain, and other countries. Approximately 40 participants are required in each arm to have 80% power in the study in order to detect a hazard ratio of 0.5 (E plus PF-06821497: E alone). Patients randomized to E alone have the option to add PF-06821497 to their regimen upon confirmed radiographic disease progression. The primary objectives are to confirm the safety and tolerability of PF-06821497 in combination with E in pts with mCRPC, and to assess the effect of PF-06821497 in combination with E versus E monotherapy on radiographic progression free survival. Secondary objectives include further evaluation of anti-tumor activity of PF-06821497, and assessment of single and multiple dose PK when given in combination with E. The impact of PF-06821497 in combination with E and of E alone in men with mCRPC on patient reported outcomes will also be assessed. Clinical trial information: NCT03460977 .

A phase II clinical study of intravesical photo dynamic therapy in patients with BCG-unresponsive NMIBC (interim analysis)

528

Background: Novel therapies are required for BCG-unresponsive, high risk non-muscle invasive bladder cancer. We report the interim results of a Phase II Clinical Study of Intravesical Photo Dynamic Therapy (PDT) in patients with BCG-Unresponsive Carcinoma In-Situ (CIS) with or without papillary disease. Methods: Out of a planned 125 patients, 42 patients have been enrolled and treated with two Study Treatments (Day 0 and Day 180) consisting of an intravesical instillation of the photosensitizer TLD-1433 (0.70 mg/cm2) followed by activation with a 520 nm intravesical laser under general anesthesia (Study Device TLC-3200) to a total of 90 J/cm2 of laser light. The primary outcome assessed was efficacy, evaluated by Complete Response (CR), at any point in time. The secondary outcome was duration of CR at 12 months, post initial CR. A tertiary objective is safety, evaluated by the incidence and severity of Adverse Events, Grade 4 or higher that do not resolve within 450 days post treatment. Patients with a negative cystoscopy and positive cytology have been defined as indeterminate response (IR), as these patients remain under investigation for lower and upper tract urothelial carcinoma. Results: Interim analyses included the first 42 patients, along with 3 patients treated in a preceding Phase Ib NMIBC clinical study assessing the safety of TLD-1433 PDT who weretreated at the same parameters, for a total of 45 patients. Data for the primary and secondary outcomes are listed in the table.The interim clinical data demonstrates a 90 day CR of 50% and a duration of response at 360 and 450 days of 35% and 21%, respectively.There have been eight Serious Adverse Events (SAE) identified (2 Grade II (tachycardia, hematuria), 3 Grade III (acute kidney injury, cellulitis), 2 Grade IV (urosepsis, depression/anxiety) and 1 Grade V). None of the SAEs were deemed to be directly related to the PDT. Conclusions: The interim data support that treatment with Photo Dynamic Therapy provides a viable treatment option for patients with BCG unresponsive CIS (+/- papillary disease) with an acceptable ongoing safety profile. Clinical trial information: NCT03945162 . [Table: see text]

Phase 3 KEYNOTE-905/EV-303: Perioperative pembrolizumab (pembro) or pembro + enfortumab vedotin (EV) for muscle-invasive bladder cancer (MIBC)

TPS585

Background: Standard of care for MIBC is neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy + pelvic lymph node dissection (RC + PLND). However, a substantial proportion of patients (pts) with MIBC are ineligible to receive cisplatin-based chemotherapy. In the phase 1b/2 KEYNOTE-869/EV-103 study, promising antitumor activity was shown in cisplatin-ineligible pts with metastatic urothelial carcinoma treated with the PD-1 inhibitor pembro combined with the nectin-4–directed antibody-drug conjugate EV. This multicenter, open-label, randomized, phase 3 KEYNOTE-905/EV-303 study (NCT03924895) is designed to evaluate the efficacy and safety of perioperative pembro alone or in combination with EV compared with RC + PLND alone in pts with MIBC who are ineligible for or decline cisplatin-based treatment. Methods: Approximately 857 adults who are cisplatin ineligible or decline cisplatin-based treatment with treatment-naive MIBC (T2-T4aN0M0 or T1-T4aN1M0), have an Eastern Cooperative Oncology Group performance status score of 0-2, and have a predominant (≥50%) urothelial histology will be randomly assigned to arm A (neoadjuvant pembro 200 mg intravenously [IV] every 3 weeks [Q3W] up to 3 cycles followed by RC + PLND and adjuvant pembro 200 mg IV Q3W up to 14 cycles), arm B (RC + PLND followed by observation), or arm C (neoadjuvant EV 1.25 mg/kg + pembro 200 mg IV Q3W up to 3 cycles followed by RC + PLND and adjuvant EV + pembro up to 6 cycles and adjuvant pembro 200 mg IV Q3W up to 8 cycles). In both the neoadjuvant and adjuvant phases of arm C, pembro will be administered on day 1 and EV will be administered on days 1 and 8 of each cycle. Dual primary end points are pathologic complete response as assessed by central pathologic review and event-free survival. Secondary end points include overall survival, disease-free survival, pathologic downstaging rates, and safety and tolerability. Enrollment is ongoing in Africa, Asia, Europe, and North America. Clinical trial information: NCT03924895 .

Final overall survival (OS) in PROpel: Abiraterone (abi) and olaparib (ola) versus abiraterone and placebo (pbo) as first-line (1L) therapy for metastatic castration-resistant prostate cancer (mCRPC)

LBA16

Background: PROpel (NCT03732820) met its primary endpoint showing significant investigator-assessed radiographic progression-free survival (rPFS) benefit for patients with mCRPC treated with abi + ola vs abi + pbo in the 1L setting (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.54–0.81, P< 0.001, data cut-off: 7/30/2021). Sensitivity analysis by blinded independent central review was consistent. A trend toward OS benefit with abi + ola was observed at the time of the primary rPFS analysis (28.6% maturity, HR 0.86, 95% CI 0.66–1.12) and a subsequent interim analysis (40.1% maturity, HR 0.83, 95% CI 0.66–1.03). We report OS and safety from the pre-planned final analysis (data cut-off: 10/12/2022). Methods: PROpel is a randomized, double-blind phase 3 trial of 1L therapy for patients with mCRPC eligible for abiraterone. Patients were prospectively assessed for homologous recombination repair mutation (HRRm) status using tumor tissue (FoundationOne CDx) and/or circulating tumor DNA (ctDNA; FoundationOne Liquid CDx) tests after randomization 1:1 to ola (300 mg twice daily [bid]) or pbo, and abi (1000 mg once daily) plus prednisone/prednisolone (5 mg bid). Treatment continued until radiographic disease progression, unacceptable toxicity or withdrawal of consent. OS was a key secondary endpoint (2-sided boundary for significance 0.0377). Aggregate results from tumor tissue and ctDNA tests were used to assign patients to HRRm/BRCAm subgroups. Results: Patient (n = 796) characteristics (including prior docetaxel, site of metastasis, symptom score and HRRm status) were generally balanced. There was a consistent trend toward OS benefit in the intention-to-treat (ITT) population with abi + ola vs abi + pbo (maturity 47.9%, HR 0.81, 95% CI 0.67–1.00, P= 0.0544), with median OS 42.1 months (m) vs 34.7 m, respectively. OS medians and HRs for HRRm, non-HRRm, BRCAm and non-BRCAm subgroups all favored abi + ola vs abi + pbo. In the abi + ola arm the most common Grade ≥3 adverse event was anemia (16.1%). Conclusions: At the prespecified final analysis in PROpel, abi + ola prolonged OS by > 7 m vs standard-of-care abiraterone (abi + pbo) in the ITT population. The median OS of > 42 m is the longest median reported to date in a phase 3 trial in 1L mCRPC. Consistent with rPFS results, a trend toward OS benefit was observed in HRRm, non-HRRm, BRCAm and non-BRCAm subgroups with greatest benefit in the BRCAm subgroup. No new long-term safety issues were identified. These results support the use of abi + ola in 1L mCRPC. Clinical trial information: NCT03732820 . [Table: see text]