Impact of Abiraterone Acetate and Enzalutamide on Symptom Burden of Patients with Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer

Mental health care utilization among men with castration-resistant prostate cancer receiving abiraterone or enzalutamide

BACKGROUND

Abiraterone and enzalutamide are castration-resistant prostate cancer (CRPC) therapies with potentially distinct associations with mental health symptoms given their differing antiandrogen targets.

METHODS

We used national Veterans Health Administration data to identify patients with CRPC who received first-line abiraterone or enzalutamide from 2010 to 2017. Using Poisson regression, we compared outpatient mental health encounters per 100 patient-months on drug between the abiraterone and enzalutamide cohorts adjusting for patient factors (e.g., age). We compared mental health encounters in the year before versus after starting therapy using the McNemar test.

RESULTS

We identified 2902 CRPC patients who received abiraterone (n = 1992) or enzalutamide (n = 910). We found no difference in outpatient mental health encounters between the two groups (adjusted incident rate ratio [aIRR] 1.04, 95% confidence interval [CI] 0.95-1.15). However, men with preexisting mental health diagnoses received 81.3% of the outpatient mental health encounters and had higher rates of these encounters with enzalutamide (aIRR 1.21, 95% CI 1.09-1.34). Among patients with ≥1 year of enrollment before and after starting abiraterone (n = 1139) or enzalutamide (n = 446), there was no difference in mental health care utilization before versus after starting treatment (17.0% of patients vs. 17.6%, p = 0.60, abiraterone; 16.4% vs. 18.4%, p = 0.26, enzalutamide).

CONCLUSION

We found no overall differences in mental health care utilization between CRPC patients who received first-line abiraterone versus enzalutamide. However, men with preexisting mental health diagnoses received the majority of mental health care and had more mental health visits with enzalutamide.

Outcomes Following Abiraterone versus Enzalutamide for Prostate Cancer: A Scoping Review

Abiraterone acetate (AA) and enzalutamide (ENZ) are commonly used for metastatic prostate cancer. It is unclear how their outcomes and toxicities vary with patient-specific factors because clinical trials typically exclude patients with significant comorbidities. This study aims to fill this knowledge gap and facilitate informed treatment decision making. A registered protocol utilizing PRISMA scoping review methodology was utilized to identify real-world studies. Of 433 non-duplicated publications, 23 were selected by three independent reviewers. ENZ offered a faster and more frequent biochemical response (30-50% vs. 70-75%), slowed progression (HR 0.66; 95% CI 0.50-0.88), and improved overall survival versus AA. ENZ was associated with more fatigue and neurological adverse effects. Conversely, AA increased risk of cardiovascular- (HR 1.82; 95% CI 1.09-3.05) and heart failure-related (HR 2.88; 95% CI 1.09-7.63) hospitalizations. Ultimately, AA was associated with increased length of hospital stay, emergency department visits, and hospitalizations (HR 1.26; 95% CI 1.04-1.53). Accordingly, total costs were higher for AA, although pharmacy costs alone were higher for ENZ. Existing data suggest that AA and ENZ have important differences in outcomes including toxicities, response, disease progression, and survival. Additionally, adherence, healthcare utilization, and costs differ. Further investigation is warranted to inform treatment decisions which optimize patient outcomes.

Real-world experience of abiraterone acetate plus prednisone in chemotherapy-naive patients with metastatic castration-resistant prostate cancer: long-term results of the prospective ABItude study

Background

Limited real-world data exist on the effectiveness and safety of abiraterone acetate plus prednisone (abiraterone hereafter) in the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) naive to chemotherapy. Most of the few available studies had a retrospective design and included a small number of patients. In the interim analysis of the ABItude study, abiraterone showed good clinical effectiveness and safety profile in the chemotherapy-naive setting over a median follow-up of 18 months.

Patients and methods

We evaluated clinical and patient-reported outcomes (PROs) of chemotherapy-naive mCRPC patients treated with abiraterone as for clinical practice in the Italian, observational, prospective, multicentric ABItude study. mCRPC patients were enrolled at abiraterone start (February 2016-June 2017) and followed up for 3 years; clinical endpoints and PROs, including quality of life (QoL) and pain, were prospectively collected. Kaplan–Meier curves were estimated.

Results

Of the 481 patients enrolled, 454 were assessable for final study analyses. At abiraterone start, the median age was 77 years, with 58.6% elderly patients and 69% having at least one comorbidity (57.5% cardiovascular diseases). Visceral metastases were present in 8.4% of patients. Over a median follow-up of 24.8 months, median progression-free survival (any progression reported by the investigators), time to abiraterone discontinuation, and overall survival were, respectively, 17.3 months [95% confidence interval (CI) 14.1-19.4 months], 16.0 months (95% CI 13.1-18.2 months), and 37.3 months (95% CI 36.5 months-not estimable); 64.2% of patients achieved ≥50% reduction in prostate-specific antigen. QoL assessed by Functional Assessment of Cancer Therapy—Prostate, the European Quality of Life 5 Dimensions 3 Level, and European Quality of Life Visual Analog Scale remained stable during treatment. Median time to pain progression according to Brief Pain Inventory data was 31.1 months (95% CI 24.8 months-not estimable). Sixty-two patients (13.1%) had at least one adverse drug reaction (ADR) and 8 (1.7%) one serious ADR.

Conclusion

With longer follow-up, abiraterone therapy remains safe, well tolerated, and active in a large unselected population.

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A prospective real-life study of abiraterone acetate in mCRPC patients.

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In 481 chemotherapy-naive mCRPC patients (median follow-up: 25 months), abiraterone plus prednisone was effective and safe.

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QoL, measured with various tools, remained stable during treatment with abiraterone plus prednisone.

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The median time to pain progression was 31.1 months.

Time on treatment with abiraterone and enzalutamide in the Patient-overview Prostate Cancer in The National Prostate Cancer Register of Sweden

BACKGROUND

There are little and inconsistent data from clinical practice on time on treatment with the androgen receptor-targeted drugs (ART) abiraterone and enzalutamide in men with metastatic castration-resistant prostate cancer (mCRPC). We assessed time on treatment with ART and investigated predictors of time on treatment.

MATERIAL AND METHODS

Time on treatment with ART in men with mCRPC in the patient-overview prostate cancer (PPC), a subregister of the National Prostate Cancer Register (NPCR) of Sweden, was assessed by use of Kaplan-Meier plots and Cox regression. To assess the representativity of PPC for time on treatment, a comparison was made with all men in NPCR who had a filling for ART in the Prescribed Drug Registry.

RESULTS

2038 men in PPC received ART between 2015 and 2019. Median time on treatment in chemo-naïve men was 10.8 (95% confidence interval 9.1-13.1) months for abiraterone and 14.1 (13.5-15.5) for enzalutamide. After the use of docetaxel, time on treatment was 8.2 (6.5-12.4) months for abiraterone and 11.1 (9.8-12.6) for enzalutamide. Predictors of a long time on treatment with ART were long duration of ADT prior to ART, low serum levels of PSA at start of ART, absence of visceral metastasis, good performance status, and no prior use of docetaxel. PPC captured 2522/6337 (40%) of all men in NPCR who had filled a prescription for ART. Based on fillings in the Prescribed Drug Registry, men in PPC had a slightly longer median time on treatment with ART compared to all men in NPCR, 9.6 (9.1-10.3) vs. 8.6 (6.3-9.1) months.

CONCLUSIONS

Time on treatment in clinical practice was similar or shorter than that in published RCTs, due to older age, poorer performance status and more comorbidities.

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.

Observational study on time on treatment with abiraterone and enzalutamide

Introduction

The aim of this study was to assess time on treatment with abiraterone and enzalutamide, two androgen receptor targeted (ART) drugs, the impact on time on treatment of time interval without drug supply between prescription fillings, and adherence to treatment.

Material and methods

By use of data from The National Prostate Cancer Register, The Prescribed Drug Registry and the Patient Registry, time on treatment with the abiraterone and enzalutamide was analyzed in all men with castration resistant prostate cancer (CRPC) in Sweden 2015–2019. Three time intervals between consecutive fillings, i.e. time without drug supply, were assessed. Adherence to the treatment was evaluated by use of the Medication Possession Ratio. Kaplan Meier analysis and multivariable Cox regression model were used to assess factors affecting time on treatment.

Results

Between January 2015 and October 2019, 1803 men filled a prescription for abiraterone and 4 534 men filled a prescription for enzalutamide. With a time interval of 30 days or less between two fillings, median time on treatment was 4.9 months (IQR 2.6–11.7) for abiraterone and 8.0 months (IQR 3.6–16.4) for enzalutamide. In sensitivity analyses, allowing for no more than 14 days without drug supply between fillings, median time on treatment was 3.9 months (IQR 2.1–9.0) for abiraterone and 5.9 months (IQR 2.8–12.1) for enzalutamide. Allowing for any time period without drug between fillings, median time on treatment was 5.7 months (IQR 2.7–14.0) for abiraterone and 9.8 months (IQR 4.4–21.0) for enzalutamide. Adherence to treatment was above 90% for both drugs.

Conclusion

Time on treatment with abiraterone and enzalutamide was shorter in clinical practice than in randomized controlled trials and varied almost two-fold with time interval without drug. Adherence to treatment was high. The main limitation of our study was the lack of data on use of chemotherapy.

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.

Fatigue, quality of life and metabolic changes in men treated with first-line enzalutamide versus abiraterone plus prednisolone for metastatic castration-resistant prostate cancer (HEAT): a randomised trial protocol

INTRODUCTION

Enzalutamide and abiraterone acetate plus prednisolone (AAP) are used in combination with androgen-deprivation therapy to further suppress the androgen stimulation of metastatic castration-resistant prostate cancer (mCRPC). First-line mCRPC treatment with enzalutamide and AAP yields similar overall survival and radiographic progression-free survival in phase III trials. Thus, treatment selection relies on patient choice, cost and side effects. The aim of this randomised trial is to investigate differences in fatigue, health-related quality of life (HRQoL) and metabolic side effects in men with mCRPC treated with first-line enzalutamide versus AAP.

METHODS AND ANALYSIS

In this ongoing open-label randomised (1:1) clinical trial, enzalutamide is compared with AAP as first-line treatment for men with mCRPC. The primary endpoint is fatigue assessed with the questionnaire Functional Assessment of Chronic Illness Therapy-Fatigue version 4. Secondary endpoints are changes in body composition (ie, fat mass, visceral adipose tissue, subcutaneous adipose tissue and lean body mass assessed with dual energy X-ray absorptiometry), glucose metabolism assessed with a 2-hour oral glucose tolerance test, serum lipids, blood pressure and HRQoL assessed with the questionnaire Functional Assessment of Cancer Therapy-Prostate (FACT-P). All study endpoints are assessed at baseline and 12-week postintervention. Blood and urine samples are collected at baseline and at time of progression on allocated treatment for future investigation of predictive and prognostic biomarkers in prostate cancer treatment. The planned sample size is 170 participants. All participants are recruited from Herlev and Gentofte Hospital, Denmark. Estimated last patient's last visit is February 2020.

ETHICS AND DISSEMINATION

The study received project approval from the National Committee on Health Research Ethics and Danish Data Protection Agency and Danish Medicines Agency (EudraCT no.: 2017-000027-99). The results of the study will be published in peer-reviewed international journals and will be presented at national and international conferences and symposiums.

TRIAL REGISTRATION NUMBER

Clinicaltrialsregister.eu (2017-000099-27).

Safety and outcomes of new generation hormone-therapy in elderly chemotherapy-naive metastatic castration-resistant prostate cancer patients in the real world

BACKGROUND

Abiraterone acetate and enzalutamide are standard treatments for chemotherapy-naive metastatic castration-resistant prostate cancer (CN-mCRPC). The purpose of this study was to evaluate the effectiveness and safety of these medications in elderly (≥ 75 years old) compared with young CN-mCRPC patients in a real-world clinical setting. Secondarily, we explored the survival prognostic value of different anatomo-clinical factors in elderly group.

METHODS

In this retrospective observational multicentre study, we included 134 consecutive CN-mCRPC patients, 64 young and 70 elderly men, who had received AA or Enz.

RESULTS

We did not find significant differences in treatment duration [16.6 months, (95% CI 9-24.2 months) vs. 16.8 months (95% CI: 6.3-27.2 months); p = 0.926] and overall survival [median not reached vs. 23.3 months (95% CI 10.2-36.3 months); p = 0.131] between the young and elderly groups. In elderly group, the only predictors of overall survival with AA or Enz were good ECOG performance status and high G8 score. Adverse events of grade ≥3 was similar in elderly group (12.9%) and in the young group (15.6%). Treatment was discontinued due to AEs in 6.3% of young group and 18.6% of elderly group.

CONCLUSIONS

Effectiveness and safety of treatment of CN-mRCPC with Abiraterone acetate and enzalutamide were similar in older and younger patients, although treatment discontinuation due to AEs was more frequent in the older age group. In addition to ECOG PS, assessment using specific geriatric scales as G8 screening tool could help to identify patients aged ≥75 who would most benefit from treatment with new-generation hormone therapy.

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

Introduction

Abiraterone acetate plus prednisone (AAP) and enzalutamide (ENZ) are commonly prescribed for metastatic castration-resistant prostate cancer (mCRPC). Data comparing their effects on patient-reported outcomes (PROs) from routine clinical practice are limited.

Methods

AQUARiUS (NCT02813408) is an ongoing, two-cohort, prospective, observational, non-randomised, multicentre, phase IV European study assessing the effects of AAP and ENZ on PROs in 211 patients with mCRPC over 12 months. Patients receive AAP or ENZ per routine clinical practice. Data on cognition, fatigue, pain and health-related quality of life are measured using the Functional Assessment of Cancer Therapy-Cognitive Function, Brief Fatigue Inventory-Short Form, Brief Pain Inventory-Short Form and European Organization for Research and Treatment of Cancer Quality of Life-C30 questionnaires, respectively.

Results

This 3-month analysis was conducted in 105 patients; 46 received AAP and 59 received ENZ. There were statistically significant differences in mean change from baseline favouring AAP over ENZ at months 1, 2 and 3 for perceived cognitive impairments and cognitive functioning. At each time-point, ENZ-treated patients had a significantly higher risk of experiencing clinically meaningful worsening in perceived cognitive impairments versus those receiving AAP.

Statistically significant differences in mean change from baseline favouring AAP over ENZ were seen for usual level of fatigue and fatigue interference at months 2 and 3 and for current fatigue and worse level of fatigue at month 3. Differences favouring AAP versus ENZ were seen for the fatigue scale of the QLQ-C30 questionnaire (months 1 and 3). There was a significantly higher risk of clinically meaningful worsening in usual level of fatigue with ENZ versus AAP at month 3.

No significant differences between cohorts were observed for pain (BPI-SF) at any time-point.

Conclusion

This analysis suggests more favourable outcomes with AAP versus ENZ for cognition and fatigue in the first 3 months of treatment initiation for mCRPC. These findings require confirmation from future analyses of data from AQUARiUS from a larger number of patients with a longer follow-up period.

Repurposing steroidogenesis inhibitors for the therapy of neuropsychiatric disorders: Promises and caveats

Steroids exert a profound influence on behavioral reactivity, by modulating the functions of most neurotransmitters and shaping the impact of stress and sex-related variables on neural processes. This background - as well as the observation that most neuroactive steroids (including sex hormones, glucocorticoids and neurosteroids) are synthetized and metabolized by overlapping enzymatic machineries - points to steroidogenic pathways as a powerful source of targets for neuropsychiatric disorders. Inhibitors of steroidogenic enzymes have been developed and approved for a broad range of genitourinary and endocrine dysfunctions, opening to new opportunities to repurpose these drugs for the treatment of mental problems. In line with this idea, preliminary clinical and preclinical results from our group have shown that inhibitors of key steroidogenic enzymes, such as 5α-reductase and 17,20 desmolase-lyase, may have therapeutic efficacy in specific behavioral disorders associated with dopaminergic hyperfunction. While the lack of specificity of these effects raises potential concerns about endocrine adverse events, these initial findings suggest that steroidogenesis modulators with greater brain specificity may hold significant potential for the development of alternative therapies for psychiatric problems. This article is part of the Special Issue entitled 'Drug Repurposing: old molecules, new ways to fast track drug discovery and development for CNS disorders'.