Evaluation of Clinically Relevant Drug-Drug Interactions and Population Pharmacokinetics of Darolutamide in Patients with Nonmetastatic Castration-Resistant Prostate Cancer: Results of Pre-Specified and Post Hoc Analyses of the Phase III ARAMIS Trial

Clinical implications of the Drug-Drug interaction in cancer patients treated with innovative oncological treatments

In the last two-decades, innovative drugs have revolutionized cancer treatments, demonstrating a significant improvement in overall survival. These drugs may present several pharmacokinetics interactions with non-oncological drugs, and vice versa, and, non-oncological drugs can modify oncological treatment outcome both with pharmacokinetic interaction and with an "off-target impact" on the tumor microenvironment or on the peripheral immune response. It's supposed that the presence of a drug-drug interaction (DDI) is associated with an increased risk of reduced anti-tumor effects or severe toxicities. However, clinical evidence that correlate the DDI presence with outcome are few, and results are difficult to compare because of difference in data collection and heterogeneous population. This review reports all the clinical evidence about DDI to provide an easy-to-use guide for DDI management and dose adjustment in solid tumors treated with inhibitors of the cyclin-dependent kinases CDK4-6, Antibody-drug conjugates, Poly ADPribose polymerase inhibitors, androgen-receptor targeted agents, or immunecheckpoints inhibitors.

Impact of Comorbidities and Drug Interactions in Patients With Metastatic Castration-Resistant Prostate Cancer Receiving Androgen Receptor Pathway Inhibitors

PURPOSE

Androgen receptor pathway inhibitors (ARPIs) are widely prescribed in metastatic castration-resistant prostate cancer (mCRPC). Real-world frequencies and potential impacts of comorbidities and concomitant medication (conmed) interactions with ARPIs are not well described.

METHODS

Patients receiving ARPIs for mCRPC were identified from the electronic Prostate Cancer Australian Database (ePAD). Demographics, clinicopathologic characteristics, and outcome data were extracted. Conmeds and comorbidities were collected from medical records. Potential interacting comorbidities were defined from trial and post-trial data. Clinically significant drug-drug interactions (DDIs) were identified using UpToDate Lexicomp and Stockley's databases. Patient characteristics, comorbidity interactions, DDIs, and outcomes were analyzed.

RESULTS

Two hundred thirty-five patients received first- or second-line ARPIs for mCRPC from 2012 to 2021, with a median follow-up of 27 months. One hundred sixteen received abiraterone acetate (AAP) and 135 received enzalutamide (ENZ). The median age was 74 years, and the median number of conmeds was 4. Clinically significant DDIs occurred in 55 (47%) AAP patients and 90 (67%) ENZ patients. Only 5% of DDIs were predicted to affect ARPI pharmacokinetics (PK) or pharmacodynamics, whereas 95% were predicted to impact conmed PK or increase toxicity risk. In patients receiving ENZ, DDIs were associated with lower PSA50 (50% v 74%, P = .04) and poorer overall survival (28 v 45 months, P = .04), although statistical significance was not maintained on multivariate analysis. No significant survival differences were seen with DDIs in patients receiving AAP. Potential interactions between comorbidities and ARPI were present in 72% on AAP and 14% on ENZ with no significant associated survival differences.

CONCLUSION

DDIs and drug-comorbidity interactions in real-world patients receiving ARPIs for mCRPC are common and may affect outcomes. Ongoing clinician education regarding DDIs is necessary to optimize patient outcomes.

New-generation androgen receptor signaling inhibitors (ARSIs) in metastatic hormone-sensitive prostate cancer (mHSPC): pharmacokinetics, drug-drug interactions (DDIs), and clinical impact

INTRODUCTION

The therapeutic scenario of metastatic hormone-sensitive prostate cancer (mHSPC) has dramatically changed in recent years, with the approval of new-generation Androgen Receptor Signaling Inhibitors (ARSIs), in combination with the androgen deprivation therapy (ADT), which was the previous standard of care. Despite showing a similar clinical efficacy, ARSIs, all of which are administered orally, are different in terms of pharmacokinetic and drug-drug interactions (DDIs).

AREAS COVERED

This review covers the main pharmacokinetic characteristics of ARSIs that have been approved for the first-line therapy of mHSPC patients, underlying the differences among these molecules and focusing on the known or possible interactions with other drugs. Full-text articles and abstracts were searched in PubMed.

EXPERT OPINION

Since prostate cancer occurs mainly in older age, comorbidities and the consequent polypharmacy increase the DDI risk in mHSPC patients who are candidates for ARSI. Waiting for new therapeutic options, in the absence of direct comparisons, pharmacokinetic knowledge is essential to guide clinicians in prescribing ARSI in this setting.

DHODH inhibition represents a therapeutic strategy and improves abiraterone treatment in castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) is an aggressive disease with poor prognosis, and there is an urgent need for more effective therapeutic targets to address this challenge. Here, we showed that dihydroorotate dehydrogenase (DHODH), an enzyme crucial in the pyrimidine biosynthesis pathway, is a promising therapeutic target for CRPC. The transcript levels of DHODH were significantly elevated in prostate tumors and were negatively correlated with the prognosis of patients with prostate cancer. DHODH inhibition effectively suppressed CRPC progression by blocking cell cycle progression and inducing apoptosis. Notably, treatment with DHODH inhibitor BAY2402234 activated androgen biosynthesis signaling in CRPC cells. However, the combination treatment with BAY2402234 and abiraterone decreased intratumoral testosterone levels and induced apoptosis, which inhibited the growth of CWR22Rv1 xenograft tumors and patient-derived xenograft organoids. Taken together, these results establish DHODH as a key player in CRPC and as a potential therapeutic target for advanced prostate cancer.

Drug-drug interaction potential among patients with nonmetastatic castration-resistant prostate cancer (nmCRPC) treated with novel androgen receptor inhibitors

BACKGROUND

Nonmetastatic castration-resistant prostate cancer (nmCRPC) patients are often older and use concurrent medications that increase the potential for drug-drug interactions (pDDIs). This study assessed pDDI prevalence in real-world nmCRPC patients treated with apalutamide, darolutamide, or enzalutamide.

RESEARCH DESIGN AND METHODS

Castrated prostate cancer patients without metastases prior to androgen receptor inhibitor initiation were identified retrospectively via Optum Clinformatics Data Mart claims data (8/2019-3/2021). The top 100 concomitant medications were assessed for pDDIs.

RESULTS

Among 1,515 patients (mean age: 77 ± 8 years; mean Charlson Comorbidity Index: 3 ± 3), 340 initiated apalutamide, 112 darolutamide, and 1,063 enzalutamide. Common concomitant medication classes were cardiovascular (80%) and central nervous system (52%). Two-thirds of the patients received ≥5 concomitant medications; 30 (30/100 medications) pDDIs were identified for apalutamide and enzalutamide each and 2 (2/100 medications) for darolutamide. Most pDDIs had risk ratings of C or D, but four for apalutamide were rated X. Approximately 58% of the patients on apalutamide, 5% on darolutamide, and 54% on enzalutamide had ≥1 identified pDDI.

CONCLUSIONS

Results showed a higher frequency of pDDIs in patients receiving apalutamide and enzalutamide vs darolutamide. The impact of these could not be determined retrospectively. DDI risk should be carefully evaluated when discussing optimal therapy for patients with nmCRPC.

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.

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

Background

ARASENS has demonstrated the efficacy and safety for darolutamide (DARO) with androgen deprivation therapy (ADT) plus docetaxel in metastasis hormone-sensitive prostate cancer (mHSPC). There is a lack of reports for DARO with ADT in mHSPC though the regimen is used in clinical from time to time. Moreover, recent studies have supported the importance of early and rapid prostate-specific antigen (PSA) reduction, which correlates with reduced disease progression and improved survival in patients with mHSPC. This study aims to evaluate PSA reduction as a primary endpoint for DARO with ADT in the treatment of mHSPC and to evaluate the real-world short-term PSA control of DARO with ADT from two leading medical centers in China.

Methods

We retrospectively reviewed the clinical records of patients with mHSPC receiving ADT and DARO (600 mg, b.i.d.). The collection of data spanned from March 1, 2022, to July 31, 2023. The main observation indicators were PSA level and drug-related adverse events (AE) after medication. PSA levels were closely monitored prior to treatment initiation and at 2-week intervals, as well as at 1, 3, and 6 months after the initiation of treatment. We also conducted an analysis to determine the proportion of patients achieving a PSA reduction of 50% or more (PSA50) and 90% or more (PSA90) as well as the percentage of patients with a notable decrease in PSA level to 0.2 ng/mL and PSA nadir of ≤0.02 ng/mL.

Results

Fifty-one patients were included in the study, with a median age of 73 years. At diagnosis of HSPC, the majority of patients had a Gleason score ≥8 (n=40, 78.40%) and a median baseline PSA level of 88 ng/mL. Approximately 45.1% (n=23) of patients had a Charlson Comorbidity Index over 1 and were receiving one or more nontumor-related treatments. The median follow-up time was 9.3 months (range, 1.16-15.8 months). The median reductions in PSA levels compared to baseline were 84.37%, 91.48%, 94.67% and 99.81% at 2 weeks, 1 month, 3 months and 6 months after administration of DARO with ADT, respectively. The median time to PSA50, PSA90, significant PSA reduction (PSA <0.2 ng/mL), and PSA nadir (PSA <0.02 ng/mL) was 0.97, 1.27, 1.98, and 2.08 months, respectively. AE mainly included fatigue (two patients) and arm pain (one patient), all of which were grade I or II AE. No grade III or AE were observed.

Conclusions

For treating prostate cancer, DARO with ADT has good early efficacy, demonstrating prompt and substantial control of PSA levels, with a favorable safety profile.

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.

Based on ARASENS trial: efficacy and safety of darolutamide as an emerging option of endocrinotherapy for metastatic hormone-sensitive prostate cancer-an updated systematic review and network meta-analysis

PURPOSE

The newly published ARASENS trial has demonstrated the clinical efficacy of darolutamide for metastatic hormone-sensitive prostate cancer (mHSPC). However, the use of darolutamide as the latest first-line androgen receptor pathway inhibitor for mHSPC has not been compared with other androgen receptor targeted agents (ARTAs). Given the lack of head-to-head randomized trials, we performed this updated meta-analysis to conduct indirect comparison for the efficacy and safety of darolutamide with other new-generation ARTAs.

METHODS

By searching the databases of PubMed, Scopus, Cochrane Library, and Embase, 9 large randomized controlled trials evaluating ARTAs for mHSPC patients were eventually screened according to PRISMA. We extracted data from overall survival, castration-resistant progression, and adverse events for network meta-analysis using the Bayesian and standard frequentist models.

RESULTS

Darolutamide combination emerged with superiority (HR = 0.68, 95%CrI = 0.57-0.81) among four androgen receptor inhibitors for patients with high Gleason score (HR = 0.71, 95%CrI = 0.59-0.86). Darolutamide was best tolerated in several androgen suppression-related adverse events (AEs).

CONCLUSION

Darolutamide appears to be an optional androgen receptor inhibitor for mHSPC patients, especially for patients with Gleason score ≥ 8. Its well-tolerated characteristic may provide a preferred drug option for patients with poor cardiovascular function and bone health.

Clinical Pharmacokinetics and Pharmacodynamics of the Next Generation Androgen Receptor Inhibitor-Darolutamide

Darolutamide is a next-generation androgen receptor signaling inhibitor (ARSI) currently approved for the treatment of nonmetastatic castration-resistant prostate cancer (nmCRPC) and metastatic hormone sensitive prostate cancer (mHSPC). Studies suggest that darolutamide also has the potential to be used to treat other stages of prostate cancer (PC), suggesting that its indications will broaden in the near future. Since ARSIs show similar efficacy for the treatment of PC, pharmacokinetic properties of these drugs and patient characteristics could help physicians decide which drug to select. This review provides an overview of the pharmacokinetic and pharmacodynamic properties of darolutamide. One of the most important pharmacological advantages of darolutamide is its low brain distribution and therefore limited seizure potential and central nervous system adverse effects. In addition, darolutamide has little drug-drug interaction potential and is unlikely to alter the exposure of other cytochrome P450 or P-glycoprotein substrates. Nevertheless, it may significantly increase the exposure of breast cancer resistant protein (BCRP) substrates. The limited solubility and bioavailability of darolutamide increases when taken together with food, regardless of the fat content. Darolutamide is excessively metabolized by oxidation and glucuronidation and excreted in the urine and feces. For this reason, dose reduction is required in patients with moderate and severe renal or severe hepatic impairment. Although no exposure-response relationship was observed with darolutamide, less advanced stages of PC showed better PSA response on treatment. Overall, darolutamide has some advantageous pharmacological properties that may lead to its preferred use, when broader registered, in selected patients across different disease stages.

Darolutamide Plus Androgen-Deprivation Therapy and Docetaxel in Metastatic Hormone-Sensitive Prostate Cancer by Disease Volume and Risk Subgroups in the Phase III ARASENS Trial

PURPOSE

For patients with metastatic hormone-sensitive prostate cancer, metastatic burden affects outcome. We examined efficacy and safety from the ARASENS trial for subgroups by disease volume and risk.

METHODS

Patients with metastatic hormone-sensitive prostate cancer were randomly assigned to darolutamide or placebo plus androgen-deprivation therapy and docetaxel. High-volume disease was defined as visceral metastases and/or ≥ 4 bone metastases with ≥ 1 beyond the vertebral column/pelvis. High-risk disease was defined as ≥ 2 risk factors: Gleason score ≥ 8, ≥ 3 bone lesions, and presence of measurable visceral metastases.

RESULTS

Of 1,305 patients, 1,005 (77%) had high-volume disease and 912 (70%) had high-risk disease. Darolutamide increased overall survival (OS) versus placebo in patients with high-volume (hazard ratio [HR], 0.69; 95% CI, 0.57 to 0.82), high-risk (HR, 0.71; 95% CI, 0.58 to 0.86), and low-risk disease (HR, 0.62; 95% CI, 0.42 to 0.90), and in the smaller low-volume subgroup, the results were also suggestive of survival benefit (HR, 0.68; 95% CI, 0.41 to 1.13). Darolutamide improved clinically relevant secondary end points of time to castration-resistant prostate cancer and subsequent systemic antineoplastic therapy versus placebo in all disease volume and risk subgroups. Adverse events (AEs) were similar between treatment groups across subgroups. Grade 3 or 4 AEs occurred in 64.9% of darolutamide patients versus 64.2% of placebo patients in the high-volume subgroup and 70.1% versus 61.1% in the low-volume subgroup. Among the most common AEs, many were known toxicities related to docetaxel.

CONCLUSION

In patients with high-volume and high-risk/low-risk metastatic hormone-sensitive prostate cancer, treatment intensification with darolutamide, androgen-deprivation therapy, and docetaxel increased OS with a similar AE profile in the subgroups, consistent with the overall population.[Media: see text].

Pharmacokinetic Interactions Between Abiraterone, Apalutamide, Darolutamide or Enzalutamide and Antithrombotic Drugs: Prediction of Clinical Events and Review of Pharmacological Information

PURPOSE

Abiraterone, apalutamide, darolutamide and enzalutamide are second-generation hormone therapies used for advanced prostate cancer; the majority of patients receiving these treatments are elderly, poly-medicated patients. Since their first market authorizations, their pharmacokinetic (PK) characteristics are increasingly well known. A potential risk of drug-drug interaction (DDI), especially with cardiovascular drugs, needs to be considered. In the case of antithrombotics, treatment imbalance can lead to severe consequences.

OBJECTIVES

To describe PK profiles of hormone therapies and antithrombotics and to predict DDIs and potentially related clinical events.

METHODS

PK profiles (CYP450 and P-gp substrate, inducer or inhibitor) are described by cross-referencing data sources (summary of product characteristics, European public assessment reports, PubMed database, Micromedex^®, etc.); a description of the potential interactions with anti-cancer drugs for each DDI and related clinical events is provided. We discuss management recommendations, including those set out in international guidelines.

RESULTS

Antithrombotics are mainly metabolized by CYP 2C9, 2C19 or 3A4. For abiraterone (CYP 2C8, 2D6 inhibitor) and darolutamide (CYP 3A4 inducer), no interaction was identified with antithrombotics. For apalutamide (CYP 2C9, 2C19, 3A4 and P-gp inducer) and enzalutamide (CYP 2C9, 2C19, 3A4 inducer and P-gp inhibitor), several PK interactions were identified with antithrombotics, which could lead to various clinical events (haemorrhage or thromboembolism).

CONCLUSION

Numerous interactions are expected between enzalutamide or apalutamide and antithrombotics, for which management should be deployed on a case-by-case basis. PK and pharmaco-epidemiological studies could shed light on whether or not there are clinically significant events related to DDIs with antithrombotics.

Darolutamide for non-metastatic castration-resistant prostate cancer: Efficacy, safety, and clinical perspectives of use

Darolutamide, a second-generation androgen receptor inhibitor (SGARI), has been shown to increase metastasis-free survival and overall survival among men with non-metastatic castration-resistant prostate cancer (nmCRPC). Its unique chemical structure potentially provides efficacy and safety advantages over the SGARIs apalutamide and enzalutamide, which are also indicated for nmCRPC. Despite a lack of direct comparisons, the SGARIs appear to have similar efficacy, safety, and quality of life (QoL) results. Indirect evidence suggests that darolutamide is preferred for its good adverse event profile, an attribute valued by physicians, patients, and their caregivers for maintaining QoL. Darolutamide and others in its class are costly; access may be a challenge for many patients and may lead to modifications to guideline-recommended regimens.

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.

Safety differences across androgen receptor inhibitors in nonmetastatic castration-resistant prostate cancer

Approval of apalutamide, enzalutamide and darolutamide has transformed the treatment landscape and guideline recommendations for patients with nonmetastatic castration-resistant prostate cancer but now raises the issue of decision-making regarding treatment selection. In this commentary, we discuss the efficacy and safety of these second-generation androgen receptor inhibitors and propose that for patients with nonmetastatic castration-resistant prostate cancer, safety considerations for these treatments are especially important. We examine these considerations in the context of patient and caregiver preferences as well as patient clinical characteristics. We further posit that consideration of treatments' safety profiles should include not only the initial direct impacts from potential treatment-emergent adverse events and drug-drug interaction events, but also the full cascade of potentially avoidable healthcare complications.

Darolutamide Maintenance in Patients With Metastatic Castration-Resistant Prostate Cancer With Nonprogressive Disease After Taxane Treatment (SAKK 08/16)

PURPOSE

To assess the efficacy and safety of darolutamide maintenance after successful taxane chemotherapy in patients with metastatic castration-resistant prostate cancer (mCRPC).

PATIENTS AND METHODS

Swiss Group for Clinical Cancer Research (SAKK) 08/16 is a randomized phase II study. Patients with mCRPC who received prior androgen-receptor pathway inhibitors (ARPIs) and subsequently had nonprogressive disease on a taxane were randomly assigned to darolutamide 600 mg twice a day or placebo twice a day. The primary end point was radiographic progression-free survival (rPFS) at 12 weeks. Secondary end points were rPFS, event-free survival, overall survival (OS), prostate-specific antigen (PSA) 50% response rate, and adverse events.

RESULTS

Overall, 92 patients were recruited by 26 centers. Prior taxane was docetaxel in 93% and cabazitaxel in 7%. Prior ARPI was abiraterone in 60%, enzalutamide in 31%, and both in 9%. rPFS at 12 weeks was significantly improved with darolutamide (64.7% v 52.2%; P = .127). Median rPFS on darolutamide was 5.5 versus 4.5 months on placebo (hazard ratio [HR], 0.54; 95% CI, 0.32 to 0.91; P = .017), and median event-free survival was 5.4 versus 2.9 months (HR, 0.46; 95% CI, 0.29 to 0.73; P = .001). PSA 50% response rate was improved (22% v 4%; P = .014). Median OS for darolutamide was 24 versus 21.3 months for placebo (HR, 0.62; 95% CI, 0.3 to 1.26; P = .181). Treatment-related adverse events were similar in both arms.

CONCLUSION

SAKK 08/16 met its primary end point, showing that switch maintenance with darolutamide after prior taxane chemotherapy and at least one ARPI resulted in a statistically significant but clinically modest rPFS prolongation with good tolerability. The median OS with darolutamide maintenance appears promising. Should these findings be confirmed in a larger trial, maintenance treatment could be a novel strategy in managing patients with mCRPC, especially those who responded well to prior ARPI.

Androgen receptor pathway inhibitors, prostate cancer, and older adults: a global Young International Society of Geriatric Oncology drug review

Prostate cancer is a disease of older adults that has undergone a significant therapeutic paradigm shift in the last decade with the emergence of novel androgen receptor pathway inhibitors (ARPis). One of the more commonly used ARPis is enzalutamide. This drug, along with darolutamide and apalutamide, initially received approvals in the metastatic castrate-resistant prostate cancer setting but is now utilized frequently in the metastatic castrate-sensitive and non-metastatic castration-resistant settings. Landmark phase III data illustrating ARPi efficacy in older adults are limited to those with excellent performance status. However, its role in unfit older prostate cancer patients remains to be explored in the context of a narrative review. This first-of-its-kind drug review aims to shed light on the most up-to-date evidence behind the unique toxicity profile of ARPis in the context of geriatric vulnerabilities such as cognitive and functional impairment, along with potential solutions and supporting evidence that exists to circumvent these issues in the vulnerable older adult.

Comparative efficacy of second-generation androgen receptor inhibitors for treating prostate cancer: A systematic review and network meta-analysis

INTRODUCTION

Second-generation androgen receptor inhibitors (SGARIs), namely enzalutamide, apalutamide, and darolutamide, are good for improving survival outcomes in prostate cancer patients, but some researchers have shown that using SGARIs increases side effects, which complicates clinicians' choice of. Therefore, we performed this network meta-analysis to assess the efficacy and toxicity of several SGARIs in the treatment of patients with metastatic hormone-sensitive prostate cancer (mHSPC), non-metastatic castration-resistant prostate cancer (nmCRPC), and metastatic castration-resistant prostate cancer (mCRPC).

METHODS

We searched PubMed, EMBASE and Cochrane Library databases from January 2000 to December 2022 to identify randomized controlled studies associated with SGARIs. We use Stata 16.0 and R 4.4.2 for data analysis, hazard ratio (HR) with 95% confidence intervals (CI) were used to assess the results.

RESULTS

This meta-analysis included 7 studies with a total of 9488 patients. In mHSPC, enzalutamide and darolutamide had a positive effect on overall survival (OS) (HR, 0.70; 95% CI, 0.59-0.82), but we did not find a difference in their efficacy to improve OS (HR, 1.19; 95% CI, 0.75-1.89). Also in nmCRPC, enzalutamide, apalutamide and darolutamide were beneficial for metastasis-free survival (MFS) (HR, 0.32; 95% CI, 0.25-0.41). Compared to darolutamide, enzalutamide (HR, 0.71; 95% CI, 0.54-0.93) and apalutamide (HR, 0.68; 95% CI, 0.51-0.91) prolonged MFS, but there was no difference in efficacy between enzalutamide and apalutamide (HR, 0.97; 95% CI, 0.73-1.28). Finally in mCRPC, there was no significant difference in indirect effects on OS between pre- and post-chemotherapy enzalutamide (HR, 0.89; 95% CI, 0.70-1.13). However, using enzalutamide before chemotherapy to improve radiographic progression-free survival (rPFS) was a better option (HR, 2.11; 95% CI, 1.62-2.73).

CONCLUSION

The SGARIs used in each trial were beneficial for the primary endpoint in the study. Firstly there was no significant difference in the effect of enzalutamide and darolutamide in improving OS in patients with mHSPC. Secondly improving MFS in patients with nmCRPC was best achieved with enzalutamide and apalutamide. In addition both pre- and post-chemotherapy use of enzalutamide was beneficial for OS in mCRPC patients, but for improving rPFS pre-chemotherapy use of enzalutamide should be preferred.The INPLASY registration number of this systematic review is INPLASY202310084.

Frequency, severity, and factors associated with clinically significant drug-drug interactions among patients with cancer attending Mbarara Regional Referral Hospital Cancer Unit, Uganda

BACKGROUND

Cancer is a major public health problem with pharmacotherapy being the cornerstone of its management. Cancer patients receive multiple drugs concurrently risking Drug-Drug Interactions (DDIs). DDIs, though avoidable, can significantly contribute to morbidity, mortality, and increased healthcare costs in this population of patients. Currently, there is no published study from Uganda on clinically significant DDIs (cs-DDIs) among cancer patients. This study identifies frequency, severity, and factors associated with cs-DDIs at Mbarara Regional Referral Hospital Cancer Unit (MRRHCU).

METHOD

A cross-sectional study was conducted among 300 cancer patients receiving chemotherapy from a tertiary care hospital in western Uganda from January-February 2022. A questionnaire and data collection form were used to collect patient data. Lexicomp® Drug interaction software was used to screen the patient drug information for DDIs and assess their severity. Predictors of DDIs were identified using logistic regression using SPSS (Statistical Package for Social Sciences).

RESULT

Three hundred participants were enrolled with a mean age of 48 ± 23.3 years. One hundred eighty-one patients experienced 495 cs-DDIs; with a mean of 1.7 ± 2.2. The prevalence of cs-DDI was 60.3% (55.0-66.0% at 95% CI). Digestive organ neoplasms were the most commonly (80, 26.7%) diagnosed category, and 'plant alkaloids and other natural products were the most frequently (143, 47.7%) used chemotherapeutic drug classes. About three-quarters of cs-DDIs were rated as category C risk (367, 74.1%) whereas over two-thirds (355, 71.7%) were moderate in severity.. Being female (aOR = 2.43 [1.23-4.48 at 95% CI]; P-value = 0.011) and use of ≥ 6 drugs concurrently (aOR = 18.82 [9.58-36.95 at 95% CI]; P-value < 0.001)) were significantly associated with cs-DDIs.

CONCLUSION

More than half of the participants experienced at-least one cs-DDI which is generally higher than what was reported in high-income settings. About three-quarters were category C and moderate in severity, and require enhanced monitoring for safety and treatment outcome. Being female and using ≥ 6 drugs were significantly associated with cs-DDIs.

Drug-Drug Interaction Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of Ipatasertib in Combination with Darolutamide in Patients with Advanced Prostate Cancer

Ipatasertib is a selective, small molecule Akt inhibitor that is currently being developed for the treatment of metastatic castration-resistant prostate cancer. Darolutamide is an androgen receptor (AR) inhibitor that is approved for the treatment of non-metastatic castration-resistant prostate cancer. Ipatasertib is metabolized by CYP3A4 to form a less active metabolite M1 (G-037720). Ipatasertib is also a weak time-dependent CYP3A4 inhibitor. Darolutamide is a mild CYP3A4 inducer and is metabolized into an active keto-darolutamide metabolite via CYP3A4. In this Phase 1b open-label, single sequence crossover study, ipatasertib pharmacokinetics safety and tolerability were evaluated in combination with darolutamide in metastatic castration-resistant prostate cancer (n = 15 patients). Specifically, the effect of 600 mg BID of darolutamide on 400 mg QD ipatasertib was evaluated in this study. Based on pharmacokinetic analysis, a mild reduction in ipatasertib AUC_{0–24 h,ss} and C_max,ss exposures was observed (~8% and ~21%, respectively) when administered in combination with darolutamide, which is considered not clinically meaningful. M1 exposures were similar with and without darolutamide administration. Darolutamide and keto-darolutamide exposures in combination with ipatasertib were similar to previously reported exposures for single agent darolutamide. Overall, the combination appears to be well-tolerated in the metastatic castration-resistant prostate cancer indication with very few AEs.

Treatment Landscape for Patients with Castration-Resistant Prostate Cancer: Patient Selection and Unmet Clinical Needs

Metastatic castration resistant prostate cancer (CRPC) is an inevitably fatal disease. However, in recent years, several treatments have been shown to improve the outcome of CRPC patients both in the non-metastatic (nmCRPC) as well as the metastatic setting (mCRPC). In nmCRPC patients with a PSA doubling time <10 months, the addition of enzalutamide, apalutamide and darolutamide to androgen deprivation therapy (ADT) compared to ADT alone resulted in improved metastases free (MFS) and overall survival (OS). For mCRPC patients, several treatment options have been shown to be effective: two taxane based chemotherapies (docetaxel and cabazitaxel), two androgen-receptor pathway inhibitors (ARPI) (abiraterone and enzalutamide), two radiopharmaceutical agents (radium 223 and 177Lutetium-PSMA-617), one immunotherapy treatment (sipuleucel-T) and two poly ADP-ribose polymerase (PARP) inhibitors (olaparib and rucaparib). Pembrolizumab is US Food and Drug Administration (FDA) approved in all MSI high solid tumors, although a very small proportion of prostate cancer patients harboring this characteristic will benefit. Despite having a broad variety of treatments available, there are still several unmet clinical needs for CRPC. The objective of this review was to describe the therapeutic landscape in CRPC patients, to identify criteria for selecting patients for specific treatments currently available, and to address the current challenges in this setting.

Decisions and dilemmas in non-metastatic castration-resistant prostate cancer management

Non-metastatic castration-resistant prostate cancer (nmCRPC) indicates a condition characterized by the progression of the prostate-specific antigen without radiographic evidence of distant metastasis on conventional imaging during androgen deprivation therapy (ADT). Recently, 3 phase III trials have shown that the addition of next-generation androgen-receptor inhibitors (ARIs) apalutamide, darolutamide, and enzalutamide to ADT allows patients with high-risk nmCRPC to delay the appearance of metastasis and to obtain long-term clinical benefits. However, the lack of head-to head comparison makes it difficult to choose one among these agents. We reviewed the literature and explained the rationale of the possible therapeutic choices. In any case, the availability of novel ARIs means that patients with nmCRPC have now a new effective treatment option that provides them a renewed hope.

Darolutamide and Survival in Metastatic, Hormone-Sensitive Prostate Cancer

BACKGROUND

Darolutamide is a potent androgen-receptor inhibitor that has been associated with increased overall survival among patients with nonmetastatic, castration-resistant prostate cancer. Whether a combination of darolutamide, androgen-deprivation therapy, and docetaxel would increase survival among patients with metastatic, hormone-sensitive prostate cancer is unknown.

METHODS

In this international, phase 3 trial, we randomly assigned patients with metastatic, hormone-sensitive prostate cancer in a 1:1 ratio to receive darolutamide (at a dose of 600 mg [two 300-mg tablets] twice daily) or matching placebo, both in combination with androgen-deprivation therapy and docetaxel. The primary end point was overall survival.

RESULTS

The primary analysis involved 1306 patients (651 in the darolutamide group and 655 in the placebo group); 86.1% of the patients had disease that was metastatic at the time of the initial diagnosis. At the data cutoff date for the primary analysis (October 25, 2021), the risk of death was significantly lower, by 32.5%, in the darolutamide group than in the placebo group (hazard ratio 0.68; 95% confidence interval, 0.57 to 0.80; P<0.001). Darolutamide was also associated with consistent benefits with respect to the secondary end points and prespecified subgroups. Adverse events were similar in the two groups, and the incidences of the most common adverse events (occurring in ≥10% of the patients) were highest during the overlapping docetaxel treatment period in both groups. The frequency of grade 3 or 4 adverse events was 66.1% in the darolutamide group and 63.5% in the placebo group; neutropenia was the most common grade 3 or 4 adverse event (in 33.7% and 34.2%, respectively).

CONCLUSIONS

In this trial involving patients with metastatic, hormone-sensitive prostate cancer, overall survival was significantly longer with the combination of darolutamide, androgen-deprivation therapy, and docetaxel than with placebo plus androgen-deprivation therapy and docetaxel, and the addition of darolutamide led to improvement in key secondary end points. The frequency of adverse events was similar in the two groups. (Funded by Bayer and Orion Pharma; ARASENS ClinicalTrials.gov number, NCT02799602.).

A Novel Artificial Intelligence-Powered Method for Prediction of Early Recurrence of Prostate Cancer After Prostatectomy and Cancer Drivers

PURPOSE

To develop a novel artificial intelligence (AI)-powered method for the prediction of prostate cancer (PCa) early recurrence and identification of driver regions in PCa of all Gleason Grade Group (GGG).

MATERIALS AND METHODS

Deep convolutional neural networks were used to develop the AI model. The AI model was trained on The Cancer Genome Atlas Prostatic Adenocarcinoma (TCGA-PRAD) whole slide images (WSI) and data set (n = 243) to predict 3-year biochemical recurrence after radical prostatectomy (RP) and was subsequently validated on WSI from patients with PCa (n = 173) from the University of Wisconsin-Madison.

RESULTS

Our AI-powered platform can extract visual and subvisual morphologic features from WSI to identify driver regions predictive of early recurrence of PCa (regions of interest [ROIs]) after RP. The ROIs were ranked with AI-morphometric scores, which were prognostic for 3-year biochemical recurrence (area under the curve [AUC], 0.78), which is significantly better than the GGG overall (AUC, 0.62). The AI-morphometric scores also showed high accuracy in the prediction of recurrence for low- or intermediate-risk PCa-AUC, 0.76, 0.84, and 0.81 for GGG1, GGG2, and GGG3, respectively. These patients could benefit the most from timely adjuvant therapy after RP. The predictive value of the high-scored ROIs was validated by known PCa biomarkers studied. With this focused biomarker analysis, a potentially new STING pathway-related PCa biomarker-TMEM173-was identified.

CONCLUSION

Our study introduces a novel approach for identifying patients with PCa at risk for early recurrence regardless of their GGG status and for identifying cancer drivers for focused evolution-aware novel biomarker discovery.

Effect of enzalutamide on PK of P-gp and BCRP substrates in cancer patients: CYP450 induction may not always predict overall effect on transporters

Drug‐drug interaction (DDI) is an important consideration for clinical decision making in prostate cancer treatment. The objective of this study was to evaluate the effect of enzalutamide, an oral androgen receptor inhibitor, on the pharmacokinetics (PK) of digoxin (P‐glycoprotein [P‐gp] probe substrate) and rosuvastatin (breast cancer resistance protein [BCRP] probe substrate) in men with metastatic castration‐resistant prostate cancer (mCRPC). This was a phase I, open‐label, fixed‐sequence, crossover study (NCT04094519). Eligible men with mCRPC received a single dose of transporter probe cocktail containing 0.25 mg digoxin and 10 mg rosuvastatin plus enzalutamide placebo‐to‐match on day 1. On day 8, patients started 160 mg enzalutamide once daily through day 71. On day 64, patients also received a single dose of the cocktail. The primary end points were digoxin and rosuvastatin plasma maximum concentration (C_max), area under the concentration‐time curve from the time of dosing to the last measurable concentration (AUC_last), and AUC from the time of dosing extrapolated to time infinity (AUC_inf). Secondary end points were enzalutamide and N‐desmethyl enzalutamide (metabolite) plasma C_max, AUC during a dosing interval, where tau is the length of the dosing interval (AUC_tau), and concentration immediately prior to dosing at multiple dosing (C_trough). When administered with enzalutamide, there was a 17% increase in C_max, 29% increase in AUC_last, and 33% increase in AUC_inf of plasma digoxin compared to digoxin alone, indicating that enzalutamide is a “mild” inhibitor of P‐gp. No PK interaction was observed between enzalutamide and rosuvastatin (BCRP probe substrate). The PK of enzalutamide and N‐desmethyl enzalutamide were in agreement with previously reported data. The potential for transporter‐mediated DDI between enzalutamide and digoxin and rosuvastatin is low in men with prostate cancer. Therefore, concomitant administration of enzalutamide with medications that are substrates for P‐gp and BCRP does not require dose adjustment in this patient population.

Nonmetastatic Castration-Resistant Prostate Cancer: Current Challenges and Trends

Prostate carcinoma is a highly prevalent biologically and clinically diverse disease, generally associated with a consistent elevation of prostate-specific antigen levels. Castration-resistant prostate cancer represents a heterogeneous clinical setting that ranges from patients with an asymptomatic prostate-specific antigen elevation after hormone blockade failure and good performance status to patients with significant debilitating symptoms and rapidly progressive disease, leading to death. Nonmetastatic castration-resistant prostate cancer is a transient disease stage defined over specific criteria established within a sensitive time period. The majority of the patients with nonmetastatic castration-resistant prostate cancer will eventually develop metastatic lesions, associated with prostate cancer-specific morbidity and mortality. However, progression to metastatic disease is a heterogeneous process still not fully understood, with studies suggesting that younger age, high Gleason score (> 7), high prostate-specific antigen levels, reduced prostate-specific antigen doubling time (< 6 months), and a rapid alkaline phosphatase rise as potentially associated factors. Although the nonmetastatic castration-resistant prostate cancer treatment landscape has substantially evolved in recent years, the disease heterogeneity makes treatment decisions for this population challenging in the effort to achieve a balance between the risk of disease progression and the toxicity of new treatments in patients who often have associated comorbidities, yet are generally asymptomatic. The present article addresses the current main challenges in nonmetastatic castration-resistant prostate cancer management, including in diagnosis, owing to the development of new imaging modalities with a direct impact in disease detection, prognostic classification, as a result of the traditionally oversimplified definition of disease aggressiveness (mainly based on prostate-specific antigen doubling time), and patient selection for the most adequate treatment.

A meta-analysis on overall survival and safety outcomes in patients with nonmetastatic castration-resistant prostate cancer treated with novel hormonal agents

Several novel androgen receptor (AR)-inhibitors have been introduced for nonmetastatic castration-resistant prostate cancer (nmCRPC) treatment, with the improvement of survival outcomes which need to be balanced against the risk of adverse events. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) investigating enzalutamide, apalutamide and darolutamide in nmCRPC patients, to assess overall survival (OS), incidence and risk of adverse drug events, adverse-events-related death and adverse-events-related treatment discontinuation. We selected three RCTs (SPARTAN, PROSPER and ARAMIS). New hormonal agents administration resulted in better OS, despite the increased risk of several any grade and grade 3-4 adverse events. In the decision-making process, careful evaluation of expected adverse events, patients' comorbidities and maintenance of quality of life are mandatory.

Clinical Pharmacokinetics of the Androgen Receptor Inhibitor Darolutamide in Healthy Subjects and Patients with Hepatic or Renal Impairment

Background

Darolutamide is a second-generation androgen receptor inhibitor approved for the treatment of nonmetastatic castration-resistant prostate cancer at a dosage of 600 mg orally twice daily.

Objective

We aimed to fully characterize the pharmacokinetic profile of darolutamide, its diastereomers, and its main active metabolite, keto-darolutamide.

Methods

Single-dose and multiple-dose pharmacokinetics of ¹⁴C-labeled and non-labeled darolutamide were evaluated in healthy subjects and patients with hepatic or renal impairment.

Results

Following darolutamide oral tablet administration, peak plasma concentrations were reached 4–6 h after dosing. Darolutamide elimination was characterized by a half-life of 13 h. Steady state was reached after approximately 2 days of twice-daily dosing. Pharmacokinetics of the diastereomers and keto-darolutamide followed similar trends to the parent compound. Darolutamide absorption from the tablet was lower than from the oral solution; tablet absolute bioavailability was ~30% in the fasted state but improved to 60–75% when given with food. The unbound fraction of darolutamide in plasma was 7.8%. The administered 1:1 ratio of the diastereomers (S,R)-darolutamide and (S,S)-darolutamide changed to ~1:6 in plasma following multiple dosing. Similar exposure and diastereomer ratios after single and multiple dosing indicate time-independent (no autoinduction) linear pharmacokinetics. Darolutamide exposure increased in patients with moderate hepatic or severe renal impairment vs healthy subjects; dose adaptation at treatment initiation should be considered in these patients.

Conclusions

Darolutamide 600 mg twice daily demonstrates predictable linear pharmacokinetics and sustainably high plasma concentrations, suggesting the potential for constant inhibition of the androgen receptor signaling pathway.

Clinical Trials Registration

NCT02418650, NCT02894385, NCT02671097.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-021-01078-y.

Management of Patients with Nonmetastatic Castration-Resistant Prostate Cancer: Recommendations of a Multidisciplinary Panel of Experts from South America

Most prostate cancer patients who undergo androgen-deprivation therapy or orchiectomy will eventually develop castration-resistant prostate cancer (CRPC), often preceded by a nonmetastatic CRPC state known as M0CRPC. The recent development of second-generation antiandrogens provides clinicians with efficacious and safe treatments for M0CRPC. However, the complexity of these patients, who typically have to deal with underlying comorbidities and polypharmacy, often challenges therapeutic decisions in this setting. The recent development of novel imaging techniques also provides clinicians with tools for detecting metastases with high sensitivity and specificity. However, the lack of evidence on the early detection of metastases and the corresponding impact on therapeutic decisions makes these techniques a double-edged sword that must be managed appropriately. Here, we present the expert view of the rapidly evolving concept of M0CRPC and provide recommendations for the identification of these patients, the appropriate use of the emerging imaging modalities, and patients’ management, particularly considering their clinical complexity and the recent development of next-generation antiandrogens.

Treating the patient and not just the cancer: therapeutic burden in prostate cancer

BACKGROUND

Prostate cancer (PC) is a leading cause of death in older men. Androgen deprivation therapy (ADT) is considered the standard-of-care for men with locally advanced disease. However, continuous androgen ablation is associated with acute and long-term adverse effects and most patients will eventually develop castration-resistant PC (CRPC). The recent approval of three, second-generation androgen receptor inhibitors (ARIs), apalutamide, enzalutamide, and darolutamide, has transformed the treatment landscape of PC. Treatment with these second-generation ARIs have produced positive trends in metastasis-free survival, progression-free survival, and overall survival. For patients with non-metastatic CRPC, who are mainly asymptomatic from their disease, maintaining quality of life is a major objective when prescribing therapy. Polypharmacy for age-related comorbidities also is common in this population and may increase the potential for drug-drug interactions (DDIs).

METHOD

This review summarizes the multiple factors that may contribute to the therapeutic burden of patients with CRPC, including the interplay between age, comorbidities, concomitant medications, the use of ARIs, and financial distress.

CONCLUSIONS

As the treatment landscape in PC continues to rapidly evolve, consideration must be given to the balance between therapeutic benefits and potential treatment-emergent adverse events that may be further complicated by DDIs with concomitant medications. Patient-centered communication is a crucial aspect of alleviating this burden, and healthcare professionals (HCPs) may benefit from training in effective patient communication. HCPs should closely and frequently monitor patient treatment responses, in order to better understand symptom onset and exacerbation. Patients also should be encouraged to participate in exercise programs, and health information and support groups, which may assist them in preventing or mitigating certain determinants of the therapeutic burden associated with PC and its management.

Darolutamide and health-related quality of life in patients with non-metastatic castration-resistant prostate cancer: An analysis of the phase III ARAMIS trial

BACKGROUND

In the ARAMIS trial, darolutamide plus androgen deprivation therapy (ADT) versus placebo plus ADT significantly improved metastasis-free survival (MFS), overall survival (OS) and time to pain progression in patients with non-metastatic castration-resistant prostate cancer (nmCRPC). Herein, we present analyses of patient-reported health-related quality of life (HRQoL) outcomes.

PATIENTS AND METHODS

This double-blind, placebo-controlled, phase III trial randomised patients with nmCRPC and prostate-specific antigen doubling time ≤10 months to darolutamide 600 mg (n = 955) twice daily or matched placebo (n = 554) while continuing ADT. The primary end-point was MFS; the secondary end-points included OS and time to pain progression. In this analysis, HRQoL was assessed by the time to deterioration using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) prostate cancer subscale (PCS) and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Prostate Cancer Module (EORTC QLQ-PR25) subscales.

RESULTS

Darolutamide significantly prolonged time to deterioration of FACT-P PCS versus placebo (hazard ratio [HR] 0.80, 95% confidence interval [CI] 0.70-0.91; P = 0.0005) at the primary analysis (cut-off date: 3rd September 2018). Time to deterioration of EORTC QLQ-PR25 outcomes showed statistically significant delays with darolutamide versus placebo for urinary (HR 0.64, 95% CI 0.54-0.76; P < 0.0001) and bowel (HR 0.78, 95% CI 0.66-0.92; P = 0.0027) symptoms. Time to worsening of hormonal treatment-related symptoms was similar between the two groups.

CONCLUSION

In patients with nmCRPC who are generally asymptomatic, darolutamide maintained HRQoL by significantly delaying time to deterioration of prostate cancer-specific quality of life and disease-related symptoms versus placebo.

Novel Treatment Strategy Using Second-Generation Androgen Receptor Inhibitors for Non-Metastatic Castration-Resistant Prostate Cancer

Non-metastatic castration-resistant prostate cancer (nmCRPC) is defined by a progressively rising prostate-specific antigen level, despite a castrate level of testosterone, in the absence of obvious radiologic evidence of metastatic disease on conventional imaging modalities. As a significant proportion of patients with nmCRPC develop metastatic diseases, the therapeutic goals of physicians for these patients are to delay metastasis development, preserve quality of life, and increase overall survival (OS). Since 2018, the treatment of nmCRPC has changed dramatically with the introduction of second-generation androgen receptor inhibitors, such as enzalutamide (ENZA), apalutamide (APA), and darolutamide (DARO). These drugs demonstrated substantial improvements in metastasis-free survival (MFS) and OS in phase III randomized clinical trials. In addition, these drugs have an excellent safety profile, preserve quality of life, and can delay disease-related symptoms. A recently published indirect meta-analysis reported that APA and ENZA showed better findings in MFS and that DARO had relatively fewer adverse effects. However, in the absence of a direct comparison, careful interpretation is required. Thus, APA, ENZA, and DARO should be considered the new standard drugs for treating nmCRPC.

Recent Development and Future Prospects of Molecular Targeted Therapy in Prostate Cancer

Prostate cancer (PC) is a rapidly increasing ailment worldwide. The previous decade has observed a rapid advancement in PC therapies that was evident from the number of FDA approvals during this phase. Androgen deprivation therapies (ADT) have traditionally remained a mainstay for the management of PCs, but the past decade has experienced the emergence of newer classes of drugs that can be used with or without the administration of ADT. FDA approved poly (ADP-ribose) polymerase inhibitors (PARPi), such as olaparib and rucaparib, after successful clinical trials against gene-mutated metastatic castration-resistant prostate cancer. Furthermore, drugs like apalutamide, darolutamide, and enzalutamide with an androgen-targeted mechanism of action have manifested superior results in non-metastatic castration-resistant prostate cancer (nmCRPC), metastatic castration-sensitive prostate cancer (mCSPC), and metastatic castration-resistant prostate cancer (mCRPC), respectively, with or without previously administered docetaxel. Relugolix, an oral gonadotropin-releasing hormone antagonist, and a combination of abiraterone acetate plus prednisone were also approved by FDA after a successful trial in advanced PC and mCRPC, respectively. This review aims to analyze the FDA-approved agents in PC during the last decade and provide a summary of their clinical trials. It also presents an overview of the ongoing progress of prospective molecules still under trial.

Metabolism and Mass Balance of the Novel Nonsteroidal Androgen Receptor Inhibitor Darolutamide in Humans

The biotransformation and excretion of darolutamide were investigated in a phase I study. Six healthy male volunteers received a single dose of 300 mg ¹⁴C-darolutamide as an oral solution in the fasted state. Plasma, urine, and feces samples were analyzed for mass balance evaluation by liquid scintillation counting (LSC). Metabolite profiling and identification were determined using liquid chromatography mass-spectrometry with off-line radioactivity detection using LSC. Complete mass balance was achieved, with mean radioactivity recovery of 95.9% within 168 hours (63.4% in urine, 32.4% in feces). The administered 1:1 ratio of (S,R)- and (S,S)-darolutamide changed to approximately 1:5, respectively, in plasma. Darolutamide and the oxidation product, keto-darolutamide, were the only components quantifiable by LSC in plasma, accounting for 87.4% of total radioactivity, with a 2.1-fold higher plasma exposure for keto-darolutamide. Aside from darolutamide, the most prominent metabolites in urine were O-glucoronide (M-7a/b) and N-glucuronide (M-15a/b), as well as pyrazole sulfates (M-29, M-24) and glucuronides (M-21, M-22) resulting from oxidative cleavage of the parent. The darolutamide diastereomers were mainly detected in feces. In vitro assays showed that darolutamide metabolism involves a complex interplay between oxidation and reduction, as well as glucuronidation. Interconversion of the diastereomers involves oxidation to keto-darolutamide, primarily mediated by CYP3A4, followed by reduction predominantly catalyzed by cytosolic reductase(s), with aldo-keto reductase 1C3 playing the major role. The latter reaction showed stereoselectivity with preferential formation of (S,S)-darolutamide. SIGNIFICANCE STATEMENT: The metabolism and excretion of darolutamide in humans revealed that oxidation (CYP3A4) and glucuronidation (UGT1A9, UGT1A1) were the main metabolic routes of elimination. Direct excretion also contributed to overall clearance. The two pharmacologically equipotent diastereomers of darolutamide interconvert primarily via oxidation to the active metabolite keto-darolutamide, followed by reduction predominantly by cytosolic reductase(s). The latter reaction showed stereoselectivity with preferential formation of (S,S)-darolutamide. Data indicate a low drug-drug interaction potential of darolutamide with inducers or inhibitors of metabolizing enzymes.

Darolutamide in hormone-sensitive and castration-resistant prostate cancer

Introduction: Important changes in the treatment of prostate cancer have taken place in recent years. Non-metastatic castration-resistant prostate cancer (nmCRPC) has been clinically delineated. In this setting, three drugs have been approved in high-risk disease: apalutamide, enzalutamide and darolutamide.Areas covered:This manuscript aims to profile darolutamide, its clinical development, pharmacologic properties, efficacy and safety. We presented the results of published clinical studies, but we also investigated ongoing ones.Expert opinion: An indirect comparison with the other two aforementioned drugs emerged. While the clinical efficacy is comparable, the toxicity profile is different for darolutamide, resulting in greater tolerance. We must wait for the results of the trials that study darolutamide in hormone-sensitive disease, both in the metastatic phase and in the localized phase. Clinical experience will also be important to determine ever more personalized treatments for patients.

Risk of Cognitive Effects in Comorbid Patients With Prostate Cancer Treated With Androgen Receptor Inhibitors

Prostate cancer (PC) is primarily a disease of older men. As the risk of neurocognitive decline increases as people age, cognitive dysfunction is a potential complication in men with PC, imposing detrimental effects on functional independence and quality of life. Importantly, risk of cognitive decline may increase with exposure to androgen deprivation therapy and other hormonal therapies. Particular consideration should be given to patients with castration-resistant PC (CRPC), many of whom require continuous, long-term androgen deprivation therapy combined with a second-generation androgen receptor inhibitor. Non-comparative evidence from interventional trials of androgen receptor inhibitors in men with non-metastatic CRPC suggests differential effects on cognitive function and central nervous system-related adverse events within this drug class. Drug-drug interactions with concomitant medications for chronic, non-malignant comorbidities differ among ARIs and thus may contribute further to cognitive impairment. Hence, establishing baseline cognitive function is a prerequisite to identifying subsequent clinical decline associated with androgen receptor-targeted therapies. Although brief, sensitive screening tools for cancer-related cognitive dysfunction are lacking, mental status can be ascertained from the initial medical history and neurocognitive examination, progressing to more in-depth evaluation when impairment is suspected. On-treatment neurocognitive monitoring should be integrated into regular clinical follow-up to preserve cognitive function and quality of life throughout disease management. This review summarizes the multiple factors that may contribute to cognitive decline in men with CRPC, awareness of which will assist clinicians to optimize individual treatment. Practical, clinic-based strategies for managing the risks for and symptoms of cognitive dysfunction are also discussed.

Treatment of nonmetastatic castration-resistant prostate cancer: focus on second-generation androgen receptor inhibitors

BACKGROUND

Nonmetastatic castration-resistant prostate cancer (nmCRPC) is defined as a rising prostate-specific antigen concentration, despite castrate levels of testosterone with ongoing androgen-deprivation therapy or orchiectomy, and no detectable metastases by conventional imaging. Patients with nmCRPC progress to metastatic disease and are at risk of developing cancer-related symptoms and morbidity, eventually dying of their disease. While patients with nmCRPC are generally asymptomatic from their disease, they are often older and have chronic comorbidities that require long-term concomitant medication. Therefore, careful consideration of the benefit-risk profile of potential treatments is required.

METHODS

In this review, we will discuss the rationale for early treatment of patients with nmCRPC to delay metastatic progression and prolong survival, as well as the factors influencing this treatment decision. We will focus on oral pharmacotherapy with the second-generation androgen receptor inhibitors, apalutamide, enzalutamide, and darolutamide, and the importance of balancing the clinical benefit they offer with potential adverse events and the consequential impact on quality of life, physical capacity, and cognitive function.

RESULTS AND CONCLUSIONS

While the definition of nmCRPC is well established, the advent of next-generation imaging techniques capable of detecting hitherto undetectable oligometastatic disease in patients with nmCRPC has fostered debate on the criteria that inform the management of these patients. However, despite these developments, published consensus statements have maintained that the absence of metastases on conventional imaging suffices to guide such therapeutic decisions. In addition, the prolonged metastasis-free survival and recently reported positive overall survival outcomes of the three second-generation androgen receptor inhibitors have provided further evidence for the early use of these agents in patients with nmCRPC in order to delay metastases and prolong survival. Here, we discuss the benefit-risk profiles of apalutamide, enzalutamide, and darolutamide based on the data available from their pivotal clinical trials in patients with nmCRPC.

Apalutamide, darolutamide and enzalutamide in nonmetastatic castration-resistant prostate cancer: a meta-analysis

Aim: Comparison of the efficacy/safety/health-related quality of life of apalutamide, enzalutamide and darolutamide in Phase III clinical trials involving patients with nonmetastatic castration-resistant prostate cancer was performed. Materials & methods: Relevant studies were identified by searching PubMed as well as conference abstracts reporting updated overall survival. Three pivotal trials were identified, SPARTAN (apalutamide), PROSPER (enzalutamide) and ARAMIS (darolutamide), and form the basis of this analysis. Results: All three drugs significantly prolonged metastasis-free survival, prostate-specific antigen response and overall survival versus placebo, and were generally well tolerated. Conclusion: Drug selection will likely be influenced by tolerability/safety and other factors, such as the propensity for drug-drug interactions and the presence of comorbidities, that affect the risk-benefit balance in individual patients.

Next-generation androgen receptor inhibitors in non-metastatic castration-resistant prostate cancer

Until recently, continuing androgen deprivation therapy (ADT) and closely monitoring patients until evolution towards metastatic castration-resistant prostate cancer (CRPC) were recommended in men with non-metastatic CRPC (nmCRPC). Because delaying the development of metastases and symptoms in these patients is a major issue, several trials have investigated next-generation androgen receptor (AR) axis inhibitors such as apalutamide, darolutamide, and enzalutamide in this setting. This review summarizes the recent advances in the management of nmCRPC, highlighting the favourable impact of next-generation AR inhibitors on metastases-free survival, overall survival and other clinically meaningful endpoints.

Darolutamide: A Review in Non-Metastatic Castration-Resistant Prostate Cancer

Oral darolutamide (Nubeqa™) is a novel second-generation, nonsteroidal, selective androgen receptor (AR) inhibitor indicated for the treatment of non-metastatic castration-resistant prostate cancer (nmCRPC). In the pivotal multinational, phase 3 ARAMIS trial in men with nmCRPC, relative to placebo plus ongoing androgen deprivation therapy (ADT), darolutamide (+ ADT) significantly prolonged metastasis-free survival (MFS) at the time of the primary analysis and overall survival (OS) at the time of the final OS analysis and was generally well tolerated in extended follow-up. Albeit long-term data from the real-world setting are required to fully define the safety profile of darolutamide, current evidence from the final ARAMIS analysis indicates that darolutamide has a low propensity for CNS-related adverse events (AEs) associated with other currently approved second-generation AR inhibitors. Given the efficacy and safety evidence from the final ARAMIS analysis and the key role of second-generation AR inhibitors in the management of nmCRPC, darolutamide + ADT represents an important emerging option for the treatment of men with nmCRPC who are at high risk of developing metastatic prostate cancer.

Efficacy and safety of darolutamide in Japanese patients with nonmetastatic castration-resistant prostate cancer: a sub-group analysis of the phase III ARAMIS trial

Background

Darolutamide, an oral androgen receptor inhibitor, has been approved for treating nonmetastatic castration-resistant prostate cancer (nmCRPC), based on significant improvements in metastasis-free survival (MFS) in the ARAMIS clinical trial. Efficacy and safety of darolutamide in Japanese patients are reported here.

Methods

In this randomized, double-blind, placebo-controlled phase III trial, 1509 patients with nmCRPC and prostate-specific antigen (PSA) doubling time ≤ 10 months were randomized 2:1 to darolutamide 600 mg twice daily or matched placebo while continuing androgen deprivation therapy. The primary endpoint was MFS.

Results

In Japan, 95 patients were enrolled and randomized to darolutamide (n = 62) or placebo (n = 33). At the primary analysis (cut-off date: September 3, 2018), after 20 primary end-point events had occurred, median MFS was not reached with darolutamide vs. 18.2 months with placebo (HR 0.28, 95% CI 0.11–0.70). Median OS was not reached due to limited numbers of events in both groups but favored darolutamide in the Japanese subgroup. Time to pain progression, time to PSA progression, and PSA response also favored darolutamide. Among Japanese patients randomized to darolutamide vs. placebo, incidences of treatment-emergent adverse events (TEAEs) were 85.5 vs. 63.6%, and incidences of treatment discontinuation due to TEAEs were 8.1 vs. 6.1%.

Conclusions

Efficacy outcomes favored darolutamide in Japanese patients with nmCRPC, supporting the clinical benefit of darolutamide in this patient population. Darolutamide was well tolerated; however, due to the small sample size, it is impossible to conclude with certainty whether differences in the safety profile exist between Japanese and overall ARAMIS populations.

Electronic supplementary material

The online version of this article (10.1007/s10147-020-01824-5) contains supplementary material, which is available to authorized users.

Treatment and resistance mechanisms in castration-resistant prostate cancer: new implications for clinical decision making?

Introduction: The armamentarium of treatment options in metastatic and non-metastatic CRPC is rapidly evolving. However, the question of how individual treatment decisions should be balanced by available predictive clinical parameters, pharmacogenetic and drug interaction profiles, or compound-associated molecular biomarkers is a major challenge for clinical practice.Areas covered: We discuss treatment and resistance mechanisms in PC with regard to their association to drug efficacy and tolerability. Current efforts of combination treatment and putative predictive biomarkers of available and upcoming compounds are highlighted with regard to their implication on clinical decision-making.Expert opinion: Several treatment approaches are delineated, where identification of resistance mechanisms in CRPC may guide treatment selection. To date, most of these candidate biomarkers will however be found only in a small subset of patients. While current approaches of combination treatment in CRPC are proving synergistic effects on cancer biology, higher complexity with regard to biomarker analysis and interaction profiles of the respective compounds may be expected. Among other aspects of personalized treatment, consideration of drug-drug interaction and pharmacogenetics is an underrepresented issue. However, the non-metastatic castration resistant prostate cancer situation may be an example for treatment selection based on drug interaction profiles in the future.

An up-to-date evaluation of darolutamide for the treatment of prostate cancer

Introduction: Currently, in prostate cancer, an increasing number of novel drugs are being used to delay its advancement to metastatic castration-resistant prostate cancer (mCRPC). Apalutamide, enzalutamide, and most recently, darolutamide (novel androgen receptor antagonists) have been approved for nonmetastatic castration-resistant prostate cancer (nmCRPC).Areas covered: The authors have evaluated darolutamide, covering all aspects of the clinical development, competence, and safety profile of the drug.Expert opinion: The unique structure of darolutamide is characterized by a high affinity for androgen receptors and detainment of antagonist activity in mutant isoforms of androgen receptors. In clinical practice, this is the main reason that makes darolutamide exceptional in terms of safety and efficacy compared to other drugs in this category. Darolutamide is considered to have the lowest probability for adverse events (AEs) compared to apalutamide and enzalutamide. Future studies, along with real-world clinical data are warranted to improve personalized treatment strategies as well as sequencing treatment between approved novel drugs.