Impact of abiraterone acetate plus prednisone or enzalutamide on fatigue and cognition in patients with metastatic castration-resistant prostate cancer: initial results from the observational AQUARiUS study

Ligand-gated ion channels as potential biomarkers for ADT-mediated cognitive decline in prostate cancer patients

Men with prostate cancer are at increased risk of developing cognitive decline by the use of second-generation androgen signaling inhibitors. To date, reliable and sensitive biomarkers that could distinguish men at high risk of cognitive dysfunction under androgen deprivation therapy (ADT) have not been characterized. We used high-throughput transcriptional profiling utilizing human prostate cancer cell culture models mimicking ADT, biomarker selection using minimal common oncology data elements-cytoscape, and bioinformatic analyses employing Advaita® iPathwayGuide and DisGeNET for identification of disease-related gene associations. Validation analysis of genes was performed on brain neuronal and glial cells by quantitative real-time polymerase chain reaction assay. Our systematic analysis of androgen deprivation-associated genes involved multiple biological processes, including neuroactive ligand-receptor interaction, axon guidance, cytokine-cytokine receptor interaction, and metabolic and cancer signaling pathways. Genes associated with neuroreceptor ligand interaction, including gamma-aminobutyric acid (GABA) A and B receptors and nuclear core proteins, were identified as top upstream regulators. Functional enrichment and protein-protein interaction network analysis highlighted the role of ligand-gated ion channels (LGICs) and their receptors in cognitive dysfunction. Gene-disease association assigned forgetfulness, intellectual disability, visuospatial deficit, bipolar disorder, and other neurocognitive impairment with upregulation of type-1 angiotensin II receptor, brain-derived neurotrophic factor, GABA type B receptor subunit 2 (GABBR2), GABRA3, GABRA5, GABRB1, glycine receptor beta, glutamate ionotropic receptor N-methyl-D-aspartate receptor (NMDA) type subunit 1, glutamate ionotropic receptor NMDA type subunit 2D, 5-hydroxytryptamine receptor 1D, interferon beta 1, and nuclear receptor subfamily 3 group C member 1 as top differentially expressed genes. Validation studies of brain glial cells, neurons, and patients on ADT demonstrated the association of these genes with cognitive decline. Our findings highlight LGICs as potential biomarkers for ADT-mediated cognitive decline. Further validation of these biomarkers may lead to future practical clinical use.

Treatment patterns and outcomes in older adults with castration-resistant prostate cancer: Analysis of an Australian real-world cohort

INTRODUCTION

Prostate cancer (PC) is the second commonest malignancy and fifth leading cause of cancer death in men worldwide. Older men are more likely to develop PC but are underrepresented in pivotal clinical trials, leading to challenges in treatment selection in the real-world setting. We aimed to examine treatment patterns and outcomes in older Australians with metastatic castration-resistant prostate cancer (mCRPC).

MATERIALS AND METHODS

We identified 753 men with mCRPC within the electronic CRPC Australian Database (ePAD). Clinical data were analysed retrospectively to assess outcomes including time to treatment failure (TTF), overall survival (OS), PSA doubling time (PSADT), PSA50 response rate, and pre-defined adverse events of special interest (AESIs). Descriptive statistics were used to report baseline characteristics, stratified by age groups (<75y, 75-85y and >85y). Groups were compared using Kruskal-Wallis and Chi-square analyses. Time-to-event analyses were performed using Kaplan-Meier methods and compared through log-rank tests. Cox proportional hazards univariate and multivariate analyses were performed to evaluate the influence of variables on OS.

RESULTS

Fifty-seven percent of men were aged <75y, 31% 75-85y, and 12% >85y. Patients ≥75y more frequently received only one line of systemic therapy (40% of <75y vs 66% 75-85y vs 68% >85y; P < 0.01). With increasing age, patients were more likely to receive androgen receptor signalling inhibitors (ARSIs) as initial therapy (42% of <75y vs 70% of 75-85y vs 84% of >85y; p < 0.01). PSA50 response rates or TTF did not significantly differ between age groups for chemotherapy or ARSIs. Patients >85y receiving enzalutamide had poorer OS but this was not an independent prognostic variable on multivariate analysis (hazard ratio [HR] 0.93(0.09-9.35); p = 0.95). PSADT >3 months was an independent positive prognostic factor for patients receiving any systemic therapy. Older patients who received docetaxel were more likely to experience AESIs (18% in <75y vs 37% 75-85y vs 33% >85y, p = 0.038) and to stop treatment as a result (21% in <75y vs 39% in 75-85y; p = 0.011).

DISCUSSION

In our mCRPC cohort, older men received fewer lines of systemic therapy and were more likely to cease docetaxel due to adverse events. However, treatment outcomes were similar in most subgroups, highlighting the importance of individualised assessment regardless of age.

Cognitive impairment after cancer treatment: mechanisms, clinical characterization, and management

Cognitive impairment is a debilitating side effect experienced by patients with cancer treated with systemically administered anticancer therapies. With around 19.3 million new cases of cancer worldwide in 2020 and the five year survival rate growing from 50% in 1970 to 67% in 2013, an urgent need exists to understand enduring side effects with severe implications for quality of life. Whereas cognitive impairment associated with chemotherapy is recognized in patients with breast cancer, researchers have started to identify cognitive impairment associated with other treatments such as immune, endocrine, and targeted therapies only recently. The underlying mechanisms are diverse and therapy specific, so further evaluation is needed to develop effective therapeutic interventions. Drug and non-drug management strategies are emerging that target mechanistic pathways or the cognitive deficits themselves, but they need to be rigorously evaluated. Clinically, consistent use of objective diagnostic tools is necessary for accurate diagnosis and clinical characterization of cognitive impairment in patients treated with anticancer therapies. This should be supplemented with clinical guidelines that could be implemented in daily practice. This review summarizes the recent advances in the mechanisms, clinical characterization, and novel management strategies of cognitive impairment associated with treatment of non-central nervous system cancers.

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.

Risk of cognitive impairment in men with advanced prostate cancer treated with NHAs: A systematic review and network meta-analysis

Novel hormonal agents (NHAs) have significantly improved outcomes in men with advanced prostate cancer. However, it remains unclear whether NHAs are associated with subsequent cognitive impairment. Thus, we sought to perform a network meta-analysis to compare the risk of cognitive impairment across NHA types. Databases (PubMed, Embase, Scopus, and Web of Science), trial registries (Clinicaltrial.gov), the European Medicines Agency, and the US Food and Drug Administration drug safety reports were searched from inception through July 30, 2021. Eligible studies were clinical trials evaluating the risk of cognitive impairment between NHAs and placebo/standard care. Two independent investigators extracted the data and performed quality assessments using the Cochrane Risk of Bias Tool and ROBINS-I. We estimated the risk ratios by the frequentist approach and calculated the ranking probabilities of all treatments with the surface under the cumulative ranking probabilities. The primary outcome and secondary outcome were odds ratio (OR) and incidence rate ratio of cognitive impairment, respectively. We identified 15 trials with 14,723 participants comparing HNAs with placebo/standard care. Treatments associated with cognitive impairment, from the most to the least, were enzalutamide (OR, 3.66; 95% confidence interval [CI], 2.84-4.73), apalutamide (OR, 1.76; 95% CI, 1.08-2.87), abiraterone acetate (OR, 1.64; 95% CI, 1.01-2.45), and darolutamide (OR, 1.11 95% CI, 0.51-2.39). After adjustment of treatment time duration, enzalutamide still had the highest risk of cognitive impairment with an incidence rate ratio of 2.17 (95% CI, 1.65-2.78). These findings suggest that NHAs, especially enzalutamide, may increase the risk of cognitive impairment compared with placebo/standard care.

Functional impact of androgen-targeted therapy on patients with castration-resistant prostate cancer

Context

Second-generation androgen receptor inhibitors (ARIs) extend metastasis-free survival, prolong overall survival, and delay symptoms when added to androgen deprivation therapy for the treatment of castration-sensitive or castration-resistant prostate cancer (CRPC). However, ARIs may adversely impact physical and cognitive function, thereby decreasing quality of life and prognosis.

Objective

To evaluate the evidence regarding the potential effects of ARIs on physical and cognitive function and to contextualize how drug-related adverse effects may influence treatment decisions in CRPC.

Evidence acquisition

We performed a literature search using MEDLINE from January 1998 to June 2020 using terms relating to prostate cancer, androgen deprivation, and physical and cognitive function. We selected 61 publications for analysis.

Evidence synthesis

Treatment-induced deterioration in physical and cognitive function may impair the independence and well-being of patients with CRPC. Patient-reported outcomes from clinical trials of ARIs provide quantitative evidence of their impact on these domains, which appears to vary between ARIs, reflecting the different adverse event profiles of these agents. Thus, the risk of physical or cognitive dysfunction may be managed or mitigated by appropriate selection of treatment options. Studies in patients with CRPC have assessed the cognitive effects of ARIs with validated instruments, whereas quantitative analysis of the impact on physical function has been limited.

Conclusion

Several validated instruments utilized for the assessment of physical and cognitive function in clinical studies have been adapted for clinical practice; however, consensus on the standardization of these assessments is required. Future clinical studies employing validated tools may generate data on the impact of ARIs and guide treatment decisions for patients with CRPC.

Patient summary

We review the hormonal therapies used to treat men with prostate cancer and the effects they have on physical and cognitive function. We discuss how to measure these effects and how this may assist when choosing treatment.

Androgen synthesis inhibition increases behavioural flexibility and mPFC tyrosine hydroxylase in gonadectomized male rats

Behavioural flexibility is essential to adapt to a changing environment and depends on the medial prefrontal cortex (mPFC). Testosterone administration decreases behavioural flexibility. It is well known that testosterone is produced in the gonads, but testosterone is also produced in the brain, including the mPFC and other nodes of the mesocorticolimbic system. It is unclear how testosterone produced in the brain versus the gonads influences behavioural flexibility. Here, in adult male rats, we assessed the effects of the androgen synthesis inhibitor abiraterone acetate (ABI) and long-term gonadectomy (GDX) on behavioural flexibility in two paradigms. In Experiment 1, ABI but not GDX reduced the number of errors to criterion and perseverative errors in a strategy set-shifting task. In Experiment 2, with a separate cohort of rats, ABI but not GDX reduced perseverative errors in a reversal learning task. In Experiment 1, we also examined tyrosine hydroxylase immunoreactivity (TH-ir), and ABI but not GDX increased TH-ir in the mPFC. Our findings suggest that neurally-produced androgens modulate behavioural flexibility via modification of dopamine signalling in the mesocorticolimbic system. These results indicate that neurosteroids regulate executive functions and that ABI treatment for prostate cancer might affect cognition.

Assessment and Management of Cognitive Function in Patients with Prostate Cancer Treated with Second-Generation Androgen Receptor Pathway Inhibitors

Preservation of cognitive function is an important outcome in oncology. Optimal patient management requires an understanding of cognitive effects of the disease and its treatment and an efficacious approach to assessment and management of cognitive dysfunction, including selection of treatments to minimize the risk of cognitive impairment. Awareness is increasing of the potentially detrimental effects of cancer-related cognitive dysfunction on functional independence and quality of life. Prostate cancer occurs most often in older men, who are more likely to develop cognitive dysfunction than younger individuals; this population may be particularly vulnerable to treatment-related cognitive disorders. Prompt identification of treatment-induced cognitive dysfunction is a crucial aspect of effective cancer management. We review the potential etiologies of cognitive decline in patients with prostate cancer, including the potential role of androgen receptor pathway inhibitors; commonly used tools for assessing cognitive function validated in metastatic castration-resistant prostate cancer and adopted in non-metastatic castration-resistant prostate cancer trials; and strategies for management of cognitive symptoms. Many methods are currently used to assess cognitive function. The prevalence and severity of cognitive dysfunction vary according to the instruments and criteria applied. Consensus on the definition of cognitive dysfunction and on the most appropriate approaches to quantify its extent and progression in patients treated for prostate cancer is lacking. Evidence-based guidance on the appropriate tools and time to assess cognitive function in patients with prostate cancer is required.

Effectiveness of first-line abiraterone versus enzalutamide among patients ≥80 years of age with metastatic castration-resistant prostate cancer: A retrospective propensity score-weighted comparative cohort study

BACKGROUND

Metastatic castration-resistant prostate cancer (mCRPC) disproportionately affects the elderly. There is limited data assessing the efficacy and tolerability of abiraterone acetate (AA) versus enzalutamide in this population.

OBJECTIVE

To compare the clinical efficacy and tolerability of AA versus enzalutamide in patients ≥ 80 years with mCRPC.

DESIGN, SETTING AND PARTICIPANTS

A retrospective propensity-weighted comparative cohort study of first-line AA versus enzalutamide among patients with mCRPC aged ≥80 years.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Inverse probability treatment weights based on propensity scores were generated to assess the treatment effect of AA versus enzalutamide on time to PSA progression (TTPP), time to progression (TTP) (first of PSA/radiographic/clinical progression) and overall survival using a weighted Cox proportional hazards model. PSA response rate (PSA RR) was compared between groups using Χ².

RESULTS AND LIMITATIONS

One hundred fifty-three patients received AA, and 125 received enzalutamide. Enzalutamide was associated with higher PSA RR (61.6% vs 43.8%, P < 0.004), and TTP (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.50-0.88, P = 0.01) but not TTPP (HR 0.73, 95% CI 0.53-1.01, P = 0.06). There were significantly more dose reductions with enzalutamide (22.9% vs 44.8%, P > 0.001) but there was no interaction between median proportion of full dose received and TTPP or TTP for either drug. Rates of treatment discontinuation (for reasons other than progression) were also significantly different between AA and enzalutamide (28.8% vs 40.8%, respectively, P = 0.04). The most common reason for dose reductions and discontinuation of enzalutamide was fatigue (30.4% and 5.6%, respectively).

CONCLUSIONS

Despite more dose reductions and a higher treatment discontinuation rate, enzalutamide was associated with a higher PSA RR and longer time to progression, than AA. Given that clinical outcomes were not adversely impacted by decreased treatment exposure, dose modification may be a useful treatment strategy to balance toxicity and tolerance.

Quality of life in men with metastatic castration-resistant prostate cancer treated with enzalutamide or abiraterone: a systematic review and meta-analysis

BACKGROUND

Enzalutamide and abiraterone acetate plus prednisone (AAP) have similar efficacy in metastatic castration-resistant prostate cancer (mCRPC), but different mechanisms of action. The aim was to compare patient-reported health-related quality of life (HRQoL) in men treated with enzalutamide vs AAP for mCRPC.

METHODS

We systematically reviewed the literature in June 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Patient-reported outcomes (PROs) until the last follow-up were summarised in a narrative synthesis. Short-term changes (12 weeks) in HRQoL, measured by the Functional Assessment of Cancer Therapy-Prostate total score (FACT-P), were compared between treatment groups and were analysed for enzalutamide and AAP in separate meta-analyses. Higher FACT-P scores indicate better HRQoL.

RESULTS

Eight studies were included in the systematic review, four of which were randomised clinical trials (RCTs) eligible for the meta-analyses. The meta-analyses showed mean within-subject FACT-P changes from baseline to week 12 of -1.3 points (95% confidence interval [CI] -2.7; 0.1) for enzalutamide and 4.7 points (95% CI -0.1; 9.6) for AAP. One RCT and three non-randomised studies directly compared enzalutamide with AAP. The RCT showed better short-term HRQoL for AAP (6.8 FACT-P-points, 95% CI 1.7; 11.8) and better long-term HRQoL for AAP in men ≥75 years (7.35 FACT-P-points, 95% CI 2.59; 12.11). The non-randomised studies showed no difference in long-term HRQoL but had all a serious risk of bias. Limitations of the included studies include that the PRO in the included trials were inconsistently reported and that only one study defined the HRQoL measures in their published protocol.

CONCLUSIONS

AAP seems to be associated with better short-term HRQoL than enzalutamide. This difference was not apparent at longer follow-up, but the long-term studies had serious risks of bias.

Preserving Well-being in Patients With Advanced and Late Prostate Cancer

Androgen deprivation therapy, alone or in combination with androgen signaling inhibitors, is a treatment option for patients with advanced prostate cancer (PC). When making treatment decisions, health care providers must consider the long-term effects of treatment on the patient's overall health and well-being. Herein, we review the effects of these treatments on the musculoskeletal and cardiovascular systems, cognition, and fall risk, and provide management approaches for each. We also include an algorithm to help health care providers implement best clinical practices and interdisciplinary care for preserving the overall well-being of PC patients.

A Clinical Evaluation of Enzalutamide in Metastatic Castration-Sensitive Prostate Cancer: Guiding Principles for Treatment Selection and Perspectives on Research

Enzalutamide was the first novel androgen receptor signaling inhibitor to demonstrate an overall survival benefit in non-metastatic and metastatic castration-sensitive prostate cancer (CSPC). It has emerged as one of the most commonly prescribed oral prostate cancer therapies (ARSI) by medical oncologists and urologists. Amongst a panoply of treatment options for metastatic CSPC, safe and effective utilization of enzalutamide dictates a detailed understanding of alternative therapy options and competing toxicity profiles. Ongoing research supports the potential for expanded enzalutamide use in earlier disease states, in combination with other systemic agents and as monotherapy (without androgen deprivation therapy). Optimal application of enzalutamide will ultimately require greater insight and attention to mitigating strategies for treatment-associated fatigue, cognitive impairment, and functional decline. This publication will comprehensively analyze the clinical evidence and guiding principles of enzalutamide use in CSPC. We will also provide a critical review of ongoing and future ARSI research focusing on pharmacologic approaches to overcome treatment resistance and strategies to improve treatment-associated functional impairment.

High Health-Related Quality of Life During Dendritic Cell Vaccination Therapy in Patients With Castration-Resistant Prostate Cancer

Background

Maintaining health-related quality of life (HRQoL) is highly desirable during systemic therapies for patients with castration-resistant prostate cancer (CRPC). Patient-reported outcome measures (PROs) were studied in our phase IIa trial on cellular-based immunotherapy with dendritic cells (DC).

Methods

We treated 21 chemo-naive asymptomatic or minimally symptomatic patients with CRPC with maximally three cycles of DC vaccinations (ClinicalTrials.gov, NCT02692976). Here, we report the impact of DC vaccination on HRQoL. PROs were assessed using the EORTC-QLQ-C30, the EORTC-QLQ-PR25, Checklist Individual Strength (CIS20-R), and Beck Depression Inventory Primary Care questionnaires. Short-term and long-term vaccine-related effects on HRQoL were studied.

Results

Questionnaires were collected at baseline (n=20), week 6 (n=19), week 12 (n=18), week 24 (n=13), week 50 (n=8) and week 100 (n=2). No clinically relevant differences in symptom-related outcome, functioning-related outcome, and Global Health Status were observed directly after the first cycle of DC vaccinations (week 6) and at follow-up (week 12) compared to baseline. HRQoL remained high throughout the vaccination cycle and six weeks afterward. In radiographic non-progressive patients, who continued DC vaccination, high HRQoL scores were observed up to one and two years after study enrolment.

Conclusions

Patients with asymptomatic or minimally symptomatic CRPC show high HRQoL throughout DC-based immunotherapy. This is a clinically relevant finding in this older-aged patient population with advanced prostate cancer.

Evaluation of Cognitive Function in Trials Testing New-Generation Hormonal Therapy in Patients with Prostate Cancer: A Systematic Review

Simple Summary

In patients with prostate cancer, the use of new-generation hormonal therapy, added to androgen deprivation therapy, requires careful evaluation of cognitive function. The aim of this systematic review is to describe the evidence about cognitive function in randomized trials testing new-generation hormonal therapy (abiraterone, enzalutamide, apalutamide, darolutamide). For each trial, we assessed the availability of both investigator-assessed cognitive impairment and disorders and patient-reported evaluation of cognitive function. Out of 19 trials, the investigator-based evaluation of cognitive impairment was available in seven (36.8%), while patient-reported evaluation of cognitive function results was presented only in one trial (5.3%). This analysis shows that, despite cognitive deterioration could be relevant in patients with prostate cancer, clinical development of new-generation hormonal drugs has not included a systematic evaluation of cognitive function.

Abstract

In patients with prostate cancer, earlier use and longer duration of new-generation hormonal therapy (NGHT), added to androgen deprivation therapy, requires careful evaluation of cognitive function. The aim of this systematic review is to describe the evidence about cognitive function in all the randomized trials (RCTs) testing NGHT (abiraterone, enzalutamide, apalutamide, darolutamide). We assessed the availability of both investigator-assessed cognitive impairment and disorders and patient-reported evaluation of cognitive function. Nineteen RCTs (17,617 patients) were included. The investigator-based evaluation of cognitive impairment was available in seven RCTs (36.8%). In total, 19/19 RCTs (100%) included patient-reported outcomes (PROs) collection, but PRO tools adopted allowed evaluation of cognitive function in two RCTs (10.5%). Among them, PRO-based cognitive function results were presented only in one RCT (5.3%): in ENZAMET, mean changes from baseline were worse with enzalutamide than with placebo, but deterioration-free survival favored enzalutamide. Despite cognitive deterioration could be relevant, clinical development of NGHT has not included a systematic evaluation of cognitive function. Assessment by investigators is at risk of underreporting, and commonly used PROs do not allow proper cognitive function analysis. Furthermore, the methodology of analysis can jeopardize the interpretation of results. Although direct comparisons are scanty, there could be differences between different NGHTs.

Investigating the impact of open label design on patient-reported outcome results in prostate cancer randomized controlled trials

Background

While open‐label randomized controlled trials (RCT) are common in oncology, some concerns have been expressed with regard to Patient‐Reported Outcomes (PRO)‐based claims stemming from these studies. We aimed to investigate the impact of open‐label design in the context of prostate cancer (PCa) RCTs with PRO data.

Methods

Randomized controlled trials of PCa with a PRO endpoint published between 2004 and 2018 were considered. RCTs were systematically evaluated on the basis of previously defined criteria, including international PRO reporting quality standards and the Cochrane Collaboration's tool for assessing Risk of Bias. The rate of concordance was estimated and compared between traditional clinical outcomes (eg, survival or tumor response) and PRO in open and blinded RCTs.

Results

We identified 110 RCTs published between 2004 and 2018, of which 62% (n = 68) were open‐label. The general characteristics of PCa RCTs were not different according to their design (open‐label vs blinded). The proportion of PCa RCTs with high‐quality PRO reporting was not different between open‐label RCTs and blinded RCTs (41.2% vs 38.1%; P = .75). No statistically significant difference was found between PRO results and concordance with traditional clinical outcomes according to the study design.

Conclusion

Our findings suggest that there is no evidence of significant bias for PROs due to the absence of blinding in the context of PCa RCTs. Further analyses should be conducted in other cancer disease sites.

Comparing the clinical efficacy and safety of abiraterone and enzalutamide in metastatic castration-resistant prostate cancer: A systematic review and meta-analysis

BACKGROUND

Two new drugs, abiraterone and enzalutamide, had recently shown beneficial effects on survival in patients with metastatic castration-resistant prostate cancer. We systematically reviewed the efficacy and safety of abiraterone and enzalutamide in metastatic castration-resistant prostate cancer in real-world practice.

METHODS

A search from PubMed, Web of Science, Cochrane, Embase was conducted up to 6 March 2019. Available articles from conferences were searched. The endpoint was prostate-specific antigen response, overall survival, progression-free survival, number of patients with any adverse event.

RESULTS

Fourteen cohort studies involving 3469 participants were included. Pooled result showed that prostate-specific antigen response was higher for patients receiving enzalutamide than abiraterone (790 patients, odds ratio (OR) 0.47, 95% confidence interval (CI) 0.29-0.77, P = 0.003, I²=59%). Enzalutamide was significantly associated with increased adverse events rate in comparison with abiraterone (730 patients, OR 0.35, 95%CI 0.13-0.92, P = 0.03, I²=65%). There was no statistical difference between abiraterone and enzalutamide with respect to perceived cognitive impairments (1856 patients, OR 0.90, 95%CI 0.29-2.76, P = 0.85, I²=5%). Enzalutamide was significantly associated with increased fatigue risk in comparison with abiraterone (2477 patients, OR 0.46, 95%CI 0.34-0.63, P＜0.00001, I²=0%).

CONCLUSIONS

Our results demonstrated that enzalutamide was more efficacious than abiraterone for patients with metastatic castration-resistant prostate cancer, but was associated with a significantly elevated risk of side effects, particularly fatigue.

A review of prostate cancer treatment impact on the CNS and cognitive function

BACKGROUND

Androgen deprivation therapy (ADT) is the backbone of systemic therapy for men with prostate cancer (PC); almost one-half of patients receive treatment during their disease course. However, a range of cognitive and other central nervous system (CNS) changes have been associated with ADT. In this review, we discuss extant data describing these complications and the mechanisms through which medications used to deliver ADT may affect them.

METHODS

We performed a MEDLINE search for appropriate papers published between January 2000 and December 2018. Relevant papers were selected and reviewed; additional publications were identified by manually assessing references from included papers, and recent congress abstracts.

RESULTS

Of ~230 search outputs, 33 were selected for inclusion. Some studies suggested a clear association between ADT and CNS effects in men with PC, whereas others did not. Accurate assessment is limited by test instrument variability, inadequate sample sizes, short follow-up duration, and limited prospective longitudinal studies. The approved second-generation androgen receptor (AR) inhibitors enzalutamide and apalutamide were associated with some CNS-related adverse events (AEs) in clinical studies, including fatigue (which can interfere with cognitive function). The androgen synthesis inhibitor abiraterone acetate was associated with a low CNS AE profile when compared with enzalutamide. The AR antagonist darolutamide demonstrated a comparable incidence of cognitive disorder in clinical trials to that of ADT alone.

CONCLUSIONS

Adequately caring for men receiving ADT requires an understanding of the symptoms, incidence and magnitude of cognitive effects, and a feasible approach to cognitive assessment and management in clinical settings. Some CNS effects could relate to blood-brain barrier penetration and direct AR inhibitor activity; drug safety profiles may differ by the degree of blood-brain barrier penetration of particular agents. Ongoing clinical trials seek to define the CNS tolerability of newer AR pathway-targeted therapy options more clearly.

The impact of patient characteristics on enzalutamide pharmacokinetics and how this relates to treatment toxicity and efficacy in metastatic prostate cancer patients

Purpose

The aim of the study is to investigate the influence of patient characteristics, age and body mass index (BMI), on pharmacokinetics of enzalutamide, and to study the relationships between drug exposure and enzalutamide efficacy and toxicity, in mCRPC patients.

Methods

Data were collected in a longitudinal cohort study (ANDROPS) and a prospective observational study (ILUMINATE), both in mCRPC patients treated with enzalutamide. To investigate the influence of age and BMI on exposure, enzalutamide and N-desmethylenzalutamide levels were compared by ANOVA. To investigate the relation of exposure versus time to progression (TTP), the sum plasma levels were divided into quartiles and compared by Kaplan–Meier analysis. To assess the relation of exposure with fatigue, plasma levels in patients experiencing fatigue vs. no fatigue were compared by and independent t test.

Results

Data of 68 mCRPC patients were included for analysis. Plasma levels were not different for age or BMI. No difference in TTP between both studies was observed (383 days (95% CI 287–859), and 567 days (95% CI 351–NR), p = 0.36). Kaplan–Meier analysis of quartiles of sum levels showed no difference for TTP. Fatigue was reported by 22 patients, no difference in sum plasma levels was observed between patients with and without fatigue.

Conclusions

We observed that age and BMI did not influence systemic exposure in patients treated with enzalutamide. No relation of exposure with efficacy or fatigue was observed. Further research using enzalutamide at a lower dose is needed to understand the relation of enzalutamide exposure and fatigue.

Management of Patients with Advanced Prostate Cancer: Report of the Advanced Prostate Cancer Consensus Conference 2019

BACKGROUND

Innovations in treatments, imaging, and molecular characterisation in advanced prostate cancer have improved outcomes, but there are still many aspects of management that lack high-level evidence to inform clinical practice. The Advanced Prostate Cancer Consensus Conference (APCCC) 2019 addressed some of these topics to supplement guidelines that are based on level 1 evidence.

OBJECTIVE

To present the results from the APCCC 2019.

DESIGN, SETTING, AND PARTICIPANTS

Similar to prior conferences, experts identified 10 important areas of controversy regarding the management of advanced prostate cancer: locally advanced disease, biochemical recurrence after local therapy, treating the primary tumour in the metastatic setting, metastatic hormone-sensitive/naïve prostate cancer, nonmetastatic castration-resistant prostate cancer, metastatic castration-resistant prostate cancer, bone health and bone metastases, molecular characterisation of tissue and blood, inter- and intrapatient heterogeneity, and adverse effects of hormonal therapy and their management. A panel of 72 international prostate cancer experts developed the programme and the consensus questions.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The panel voted publicly but anonymously on 123 predefined questions, which were developed by both voting and nonvoting panel members prior to the conference following a modified Delphi process.

RESULTS AND LIMITATIONS

Panellists voted based on their opinions rather than a standard literature review or formal meta-analysis. The answer options for the consensus questions had varying degrees of support by the panel, as reflected in this article and the detailed voting results reported in the Supplementary material.

CONCLUSIONS

These voting results from a panel of prostate cancer experts can help clinicians and patients navigate controversial areas of advanced prostate management for which high-level evidence is sparse. However, diagnostic and treatment decisions should always be individualised based on patient-specific factors, such as disease extent and location, prior lines of therapy, comorbidities, and treatment preferences, together with current and emerging clinical evidence and logistic and economic constraints. Clinical trial enrolment for men with advanced prostate cancer should be strongly encouraged. Importantly, APCCC 2019 once again identified important questions that merit assessment in specifically designed trials.

PATIENT SUMMARY

The Advanced Prostate Cancer Consensus Conference provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference, which has been held three times since 2015, aims to share the knowledge of world experts in prostate cancer management with health care providers worldwide. At the end of the conference, an expert panel discusses and votes on predefined consensus questions that target the most clinically relevant areas of advanced prostate cancer treatment. The results of the voting provide a practical guide to help clinicians discuss therapeutic options with patients as part of shared and multidisciplinary decision making.

Cancer-related cognitive impairment: an update on state of the art, detection, and management strategies in cancer survivors

BACKGROUND

Advances in diagnostic and therapeutic strategies in oncology have significantly increased the chance of survival of cancer patients, even those with metastatic disease. However, cancer-related cognitive impairment (CRCI) is frequently reported in patients treated for non-central nervous system cancers, particularly during and after chemotherapy.

DESIGN

This review provides an update of the state of the art based on PubMed searches between 2012 and March 2019 on 'cognition', 'cancer', 'antineoplastic agents' or 'chemotherapy'. It includes the most recent clinical, imaging and pre-clinical data and reports management strategies of CRCI.

RESULTS

Evidence obtained primarily from studies on breast cancer patients highlight memory, processing speed, attention and executive functions as the most cognitive domains impaired post-chemotherapy. Recent investigations established that other cancer treatments, such as hormone therapies and targeted therapies, can also induce cognitive deficits. Knowledge regarding predisposing factors, biological markers or brain functions associated with CRCI has improved. Factors such as age and genetic polymorphisms of apolipoprotein E, catechol-O-methyltransferase and BDNF may predispose individuals to a higher risk of cognitive impairment. Poor performance on neuropsychological tests were associated with volume reduction in grey matter, less connectivity and activation after chemotherapy. In animals, hippocampus-based memory and executive functions, mediated by the frontal lobes, were shown to be particularly susceptible to the effects of chemotherapy. It involves altered neurogenesis, mitochondrial dysfunction or brain cytokine response. An important next step is to identify strategies for managing cognitive difficulties, with primary studies to assess cognitive training and physical exercise regimens.

CONCLUSIONS

CRCI is not limited to chemotherapy. A multidisciplinary approach has improved our knowledge of the complex mechanisms involved. Nowadays, studies evaluating cognitive rehabilitation programmes are encouraged to help patients cope with cognitive difficulties and improve quality of life during and after cancer.

PREVALENCE OF FATIGUE AND IMPACT ON QUALITY OF LIFE IN CASTRATION-RESISTANT PROSTATE CANCER PATIENTS: the VITAL study

BACKGROUND

Fatigue is one of the most prevalent symptoms among cancer patients. Specifically, in metastatic castration-resistant prostate cancer (mCRPC) patients, fatigue is the most common adverse event associated with current treatments. The purpose of this study is to describe the prevalence of fatigue and its impact on quality of life (QoL) in patients with CRPC in routine clinical practice.

METHODS

This was a cross-sectional, multicentre study. Male chemo-naïve adults with high-risk non-metastatic (M0) CRPC and metastatic (M1) CRPC (mCRPC) were eligible. Fatigue was measured using the Brief Fatigue Inventory (BFI) and QoL was assessed using the Functional Assessment of Cancer Therapy questionnaire for patients with prostate cancer (FACT-P) and the FACT-General (FACT-G) questionnaire. Data were analysed using Mann-Whitney or Kruskal-Wallis tests (non-parametric distribution), a T-test or an ANOVA (parametric distribution) and the Fisher or chi-squared tests (categorical variables).

RESULTS

A total of 235 eligible patients were included in the study (74 [31.5%] with M0; and 161 [68.5%] with M1). Fatigue was present in 74%, with 38.5% of patients reporting moderate-to-severe fatigue. Mean FACT-G and FACT-P overall scores were 77.6 ± 16.3 and 108.7 ± 21.4, respectively, with no differences between the CRPC M0 and CRPC M1 subgroups. Fatigue intensity was associated with decreased FACT-G/P scores, with no differences between groups. Among 151 mCRPC patients with available treatment data, those treated with abiraterone-prednisone ≥3 months showed a significant reduction in fatigue intensity (p = 0.043) and interference (p = 0.04) compared to those on traditional hormone therapy (HT). Patients on abiraterone-prednisone ≥3 months showed significantly better FACT-G/P scores than patients on HT (p = 0.046 and 0.018, respectively).

CONCLUSION

Our data show a high prevalence and intensity of fatigue and its impact on QoL in chemo-naïve CRPC patients. There is an association between greater fatigue and less QoL, irrespective of the presence or absence of metastasis. Chemo-naïve mCRPC patients receiving more than 3 months of abiraterone acetate plus prednisone showed an improvement of fatigue and QoL when compared to those on traditional HT.

TRIAL REGISTRATION

Not applicable since it is not an interventional study.

Impact of Abiraterone Acetate plus Prednisone or Enzalutamide on Patient-reported Outcomes in Patients with Metastatic Castration-resistant Prostate Cancer: Final 12-mo Analysis from the Observational AQUARiUS Study

BACKGROUND

Few studies have examined patient-reported outcomes (PROs) with abiraterone acetate plus prednisone (abiraterone) versus enzalutamide in metastatic castration-resistant prostate cancer (mCRPC).

OBJECTIVE

To determine the impact of abiraterone and enzalutamide on PROs.

DESIGN, SETTING, AND PARTICIPANTS

AQUARiUS (NCT02813408) was a prospective, 12-mo, observational study in patients with mCRPC from Denmark, France, and the UK.

INTERVENTION

Abiraterone or enzalutamide treatment according to routine practise.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

PROs were collected over 12 mo using Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog), Brief Fatigue Inventory-Short Form (BFI-SF), Brief Pain Inventory-Short Form, and European Organisation for Research and Treatment of Cancer-Quality of Life Questionnaire (QLQ-C30) at baseline and routine visits. Outcomes included mean change in PROs, patients with clinically meaningful worsening (CMW) in PROs, and safety. Data were analysed using repeated measures linear and logistic models adjusted for baseline characteristics.

RESULTS AND LIMITATIONS

Abiraterone-treated (N = 105) and enzalutamide-treated (N = 106) patients were included. Key PRO items (cognitive impairments and fatigue) were significantly (p < 0.05) in favour of abiraterone versus enzalutamide during the study. "Perceived cognitive impairment" and "comments from others" (FACT-Cog); "fatigue right now", "usual level of fatigue", and "worst level of fatigue" (BFI-SF); and "cognitive functioning" and "fatigue" (QLQ-C30) were significantly in favour of abiraterone over enzalutamide for three or more consecutive periods up to month 12. From study initiation, significantly fewer patients receiving abiraterone experienced one or more CMW episode in cognition and fatigue. Fatigue and asthenia (adverse events) were lower with abiraterone than with enzalutamide (5% vs 15% and 10% vs 11%, respectively). There were no treatment-related deaths. Limitations included lack of randomisation.

CONCLUSIONS

In a real-world setting, this 12-mo analysis suggests an advantage of abiraterone acetate plus prednisone over enzalutamide on fatigue and cognitive function; this finding occurred early after treatment initiation. This difference should be considered when choosing treatment.

PATIENT SUMMARY

This study looked at the effect of two treatments (abiraterone acetate plus prednisone and enzalutamide) for metastatic castration-resistant prostate cancer on patient quality of life over 12 mo. Using established questionnaires, patients reported that they experienced less fatigue and cognitive impairments (including memory loss and reduced thinking abilities) with abiraterone acetate plus prednisone than with enzalutamide.

Results of a Real-world Study of Enzalutamide and Abiraterone Acetate With Prednisone Tolerability (REAAcT)

BACKGROUND

The objective of this study was to evaluate differences in tolerability in patients with metastatic castration-resistant prostate cancer treated with enzalutamide (ENZA) or abiraterone acetate plus prednisone (AA+P).

PATIENTS AND METHODS

This was a phase IV, prospective, open-label, multicenter, real-world study. Patients were prescribed ENZA or AA+P at the treating physician's discretion. Computerized tests of 4 cognitive domains (Cogstate), patient-reported outcomes (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 [EORTC QLQ-30], Functional Assessment of Chronic Illness Therapy-Fatigue [FACIT-Fatigue], Functional Assessment of Cancer Therapy-Cognitive Function [FACT-Cog]), and patient/caregiver surveys were assessed at baseline and 2 months. Safety data were collected.

RESULTS

Of 100 treated patients, 92 were evaluable (46/arm). Baseline characteristics were similar, with mild cognitive impairment observed in ∼20% of patients. The FACIT-Fatigue demonstrated a statistically significant worsening from baseline of -4.00 (95% confidence interval, -6.61 to -1.39) for ENZA compared with AA+P, -0.01 (95% confidence interval, -2.40 to 2.38). Overall, more adverse events (AEs) and more AEs of fatigue were reported with ENZA versus AA+P (52% vs. 36% and 26% vs. 8%, respectively). Grade 3/4 AEs were similar (4% vs. 6%). Unique neuropsychiatric AEs reported with ENZA included amnesia, cognitive disorders, memory impairment, and confusional state; those for AA+P included cerebrovascular accident, presyncope, and spinal cord compression. Clinically meaningful cognitive decline was seen in 4 patients on ENZA versus 1 patient on AA+P. However, the overall mean changes from baseline for the Cogstate tests, the EORTC QLQ-C30, and the FACT-Cog assessment were similar and showed no meaningful change. Caregiver survey responses noted more fatigue with ENZA and more moodiness with AA+P compared with patient responses.

CONCLUSIONS

Although baseline values were similar, more fatigue and neurocognitive differences were observed with ENZA compared with AA+P.

Enzalutamide: A Review in Castration-Resistant Prostate Cancer

Oral enzalutamide (Xtandi^®), a second generation androgen receptor inhibitor, is indicated for the treatment of castration-resistant prostate cancer (CRPC) in numerous countries worldwide, with specific indications in this patient population varying between individual countries. Based on extensive experience in the clinical trial and/or real-world settings, oral enzalutamide 160 mg once daily is an effective and generally well tolerated treatment in a broad spectrum of patients with CRPC, including in nonmetastatic and metastatic disease and in chemotherapy-naive and -experienced metastatic CRPC. Enzalutamide is an emerging option for the treatment of men with nonmetastatic CRPC who are at high-risk for developing metastatic disease, and remains an important first-line option in chemotherapy-naive or -experienced patients with metastatic CRPC.