Prostate cancer management in Southeast Asian countries: a survey of clinical practice patterns

Background

Prostate cancer (PC) has a serious public health impact, and its incidence is rising due to the aging population. There is limited evidence and consensus to guide the management of PC in Southeast Asia (SEA). We present real-world data on clinical practice patterns in SEA for advanced PC care.

Method

A paper-based survey was used to identify clinical practice patterns and obtain consensus among the panelists. The survey included the demographics of the panelists, the use of clinical guidelines, and clinical practice patterns in the management of advanced PC in SEA.

Results

Most panelists (81%) voted prostate-specific antigen (PSA) as the most effective test for early PC diagnosis and risk stratification. Nearly 44% of panelists agreed that prostate-specific membrane antigen positron emission tomography-computed tomography imaging for PC diagnostic and staging information aids local and systemic therapy decisions. The majority of the panel preferred abiraterone acetate (67%) or docetaxel (44%) as first-line therapy for symptomatic mCRPC patients. Abiraterone acetate (50%) is preferred over docetaxel as a first-line treatment in metastatic castration-sensitive prostate cancer patients with high-volume disease. However, the panel did not support the use of abiraterone acetate in non-metastatic castration-resistant prostate cancer (nmCRPC) patients. Apalutamide (75%) is the preferred treatment option for patients with nmCRPC. The cost and availability of modern treatments and technologies are important factors influencing therapeutic decisions. All panelists supported the use of generic versions of approved therapies.

Conclusion

The survey results reflect real-world management of advanced PC in a SEA country. These findings could be used to guide local clinical practices and highlight the financial challenges of modern healthcare.

Concomitant antihypertensive medication and outcome of patients with metastatic castration-resistant prostate cancer receiving enzalutamide or abiraterone acetate

BACKGROUND

The introduction of novel hormonal therapies represented by enzalutamide (ENZ) and abiraterone acetate (ABI) has reached a great progress in the treatment of metastatic castration-resistant prostate cancer (mCRPC). The majority of mCRPC patients are elderly suffering from chronic co-morbidities requiring use of various concomitant medications. In the present study, we focused on impact of concomitant antihypertensive medication on the outcomes of mCRPC patients treated with ENZ or ABI.

METHODS

In total, 300 patients were included and their clinical data were retrospectively analyzed.

RESULTS

Angiotensin-converting enzyme inhibitors (ACEIs) represented the only concomitant medication significantly associated with survival. The median radiographic progression-free survival (rPFS) and overall survival (OS) for patients using ACEIs were 15.5 and 32.3 months compared to 10.7 and 24.0 months for those not using ACEIs (p = 0.0053 and p = 0.0238, respectively). Cox multivariable analysis revealed the use of ACEIs a significant predictive factor for both rPFS (HR = 0.704, p = 0.0364) and OS (HR = 0.592, p = 0.0185).

CONCLUSION

The findings of this study suggest an association between the concomitant use of ACEIs and longer survival of mCRPC patients receiving ENZ or ABI therapy.

Abiraterone-Associated Mineralocorticoid Excess: A Case Report

Abiraterone acetate causes an adrenocorticotropic hormone (ACTH)-mediated mineralocorticoid excess. We present a 77-year-old man with prostate adenocarcinoma who developed signs and symptoms of mineralocorticoid excess while on abiraterone and discuss its pathophysiology and treatment options. The patient developed hypokalemia, metabolic alkalosis, and hypertension, indicative of increased mineralocorticoid activity, confirmed by elevated ACTH, corticosterone, and deoxycorticosterone levels. Abiraterone inhibits cytochrome P450c17 (CYP17A1), thus inhibiting testosterone and cortisol synthesis. Diminished cortisol synthesis, in turn, leads to excessive mineralocorticoid precursor production mediated by ACTH, leading to enhanced sodium absorption and potassium excretion. Abiraterone is often prescribed with low-dose prednisone to suppress ACTH; however, this strategy may not provide physiological glucocorticoid levels, resulting in ACTH-mediated mineralocorticoid excess in some patients. High-dose steroids or mineralocorticoid antagonists may activate mutant androgen receptors in prostate cancer tissue; therefore, amiloride is suggested for managing residual mineralocorticoid activity. This case highlights the importance of being vigilant for the signs and symptoms of mineralocorticoid excess in patients on abiraterone.

Longitudinal assessment of plasma androgen receptor copy number predicts overall survival in subsequent treatment lines in castration-resistant prostate cancer: analysis from a prospective trial

BACKGROUND

Baseline plasma androgen-receptor copy number (AR-CN) is a promising biomarker for metastatic castration-resistant prostate cancer (mCRPC) outcome and treatment response; however, the role of its longitudinal testing is unproven. We aimed to evaluate the prognostic role of AR-CN assessed before subsequent treatment lines in mCRPC patients.

METHODS

A subgroup analysis of a prospective multicenter biomarker trial (IRSTB030) was carried out. Plasma AR-CN status (classified as normal or gain, cut-off value = 2) was assessed with digital PCR before each treatment line.

RESULTS

Forty mCRPC patients receiving sequentially docetaxel, cabazitaxel and an AR signaling inhibitor (abiraterone or enzalutamide) were analyzed. At multivariate analysis, at each assessment overall survival (OS) was independently correlated with AR-CN status [first line: hazard ratio (HR) 4.1 [95% confidence interval (CI) 1.6-10.5]; second line: HR 2.4 (95% CI 1.1-5.3); third line: HR 2.1 (95% CI 1.0-4.3)] and median prostate-specific antigen [first line: HR 4.4 (95% CI 1.8-10.9); second line: HR 3.4 (95% CI 1.6-7.2); third line: HR 2.5 (95% CI 1.2-5.6)]. In the three subsequent assessments, AR-CN status changed from normal to gain in 15 (38%) patients. These patients had longer OS (47 months) compared with patients presenting AR-CN gain from first assessment (36 months), but shorter than those maintaining normal AR-CN (69 months) (P = 0.003).

CONCLUSIONS

Plasma AR-CN correlates with survival not only at baseline (before first treatment), but also in the assessments before the following lines. Interestingly, AR-CN status may change from normal to gain across subsequent treatments in a significant number of cases, identifying a group of patients with intermediate outcomes. Longitudinal assessment of AR-CN status could represent a promising method to capture mCRPC intrinsic heterogeneity and to improve clinical management.

Cortisol as Biomarker for CYP17-Inhibition is Associated with Therapy Outcome of Abiraterone Acetate

BACKGROUND

Abiraterone acetate is an irreversible 17α-hydroxylase/C17, 20-lyase (CYP17) inhibitor approved for the treatment of metastatic castration-resistant prostate cancer (mCRPC) patients. Inhibition of this enzyme leads to low testosterone and cortisol levels in blood. There is growing evidence that clinical efficacy of abiraterone is related to the rate of suppression of serum testosterone. However, quantification of very low levels of circulating testosterone is challenging. We therefore aimed to investigate whether circulating cortisol levels could be used as a surrogate biomarker for CYP17 inhibition in patients with mCRPC treated with abiraterone acetate.

PATIENTS AND METHODS

mCRPC patients treated with abiraterone acetate were included. Abiraterone and cortisol levels were measured with a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS). On treatment cortisol and abiraterone concentrations were related to treatment response and progression free survival.

RESULTS

In total 117 patients were included with a median cortisol concentration of 1.13 ng/ml (range: 0.03 - 82.2) and median abiraterone trough concentration (Cmin) of 10.2 ng/ml (range: 0.58 - 92.1). In the survival analyses, abiraterone Cmin ≥ 8.4 ng/mL and cortisol  < 2.24 ng/mL were associated with a longer prostate-specific antigen (PSA) independent progression-free survival than patients with an abiraterone concentration  ≥ 8.4 ng/mL and a cortisol concentration ≥ 2.24 ng/mL (13.8 months vs. 3.7 months).

CONCLUSION

Our study shows that cortisol is not an independent predictor of abiraterone response in patients with mCRPC, but it is of added value in combination with abiraterone levels, to predict a response on abiraterone.

The Geriatric Nutritional Risk Index Predicts Prognosis in Japanese Patients with LATITUDE High-Risk Metastatic Hormone-Sensitive Prostate Cancer: A Multi-Center Study

Malnutrition is associated with prognosis in cancer. The geriatric nutritional risk index (GNRI), based on the ratio of actual to ideal body weight and also serum albumin level, is a simple screening tool for assessing nutrition. We investigated the GNRI as a prognostic factor for oncological outcomes in patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC) using a Japanese multicenter cohort. This study included a total of 175 patients with LATITUDE high-risk mHSPC, of whom 102 had received androgen deprivation therapy (ADT) plus upfront abiraterone acetate, and 73 had received ADT plus bicalutamide (Bica), from 14 institutions associated with the Tokai Urologic Oncology Research Seminar. Patients were classified into GNRI-low (<98) or GNRI-high (≥98) groups. The GNRI was based on the body mass index and serum albumin level. Kaplan-Meier analysis revealed that the median overall survival (OS) of a GNRI-low group (median 33.7 months; 95% confidence interval [CI]: 26.2-not reached [NR]) was significantly worse than that of a GNRI-high group (median: NR; 95% CI: NR-NR; p < 0.001). Multivariate analysis identified Bica and low GNRI (<98) as independent prognostic factors for reduced times to both castration-resistant prostate cancer and OS, and, therefore, a poor prognosis. Our findings indicate the GNRI may be a practical prognostic indicator in the evaluation of survival outcomes in patients with LATITUDE high-risk mHSPC.

Real-world survival outcome comparing abiraterone acetate plus prednisone and enzalutamide for nonmetastatic castration-resistant prostate cancer

BACKGROUND

There is little evidence of abiraterone acetate (AA) plus prednisone for patients with non-metastatic castration-resistant prostate cancer (nmCRPC). In this study, we conducted a comparative analysis of real-world survival outcomes between AA plus prednisone and enzalutamide (Enz) in patients with nmCRPC, utilizing our consortium dataset.

MATERIALS AND METHODS

The clinical records of 133 nmCRPC patients treated with first-line Enz or AA plus prednisone were analyzed. The primary endpoints of the study were overall survival (OS) and cancer-specific survival (CSS). Cumulative incidence function (CIF) using Fine and Gray models was also utilized to assess non-cancer-caused death considering the competing risk of cancer-caused death.

RESULTS

During a median follow-up of 36 months, 34 patients (25.6%) had deceased, with a median OS of 99 months in the entire cohort. There were no significant differences in comorbidities between the Enz and AA groups. Time to PSA progression (TTPP: HR 0.81, 95% CI 0.51-1.30, P = 0.375) and CSS (HR 1.32, 95% CI 0.55-3.44, P = 0.5141) were comparable between the two groups. However, intriguingly, there was a trend towards shorter OS in patients treated with AA plus prednisone compared to Enz (HR 0.57, 95% CI 0.29-1.12, P = 0.0978, median of 99 and 69 months in Enz and AA groups, respectively). CIF analysis revealed that nmCRPC patients treated with AA plus prednisone were more likely to result in non-cancer-caused death than those treated with Enz (HR 5.22, 95% CI 1.88-14.50, P = 0.0014).

CONCLUSIONS

Our real-world survival analysis suggests that while AA plus prednisone may demonstrate comparable treatment efficacy to Enz in the context of nmCRPC, there may be an increased risk of non-cancer-caused death. Physicians should take into consideration this information when making treatment decisions for patients with nmCRPC.

A new method to quantify the effect of co-medication on the efficacy of abiraterone in metastatic castration-resistant prostate cancer patients

Background and Objective: Patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate (AA) have co-morbidities treated with different drugs. The aim was to quantify the potential effect of co-medications on AA treatment duration (TD) and overall survival (OS). Methods: A new parameter, called "individual drug score" (IDS) was calculated by summing the "drug score"-s (DS) of all co-medications for each patient. The DS was determined by quantifying the effect of a given co-drug on enzymes involved in steroidogenesis and metabolism of AA. The correlation between log (IDS) and TD was tested by non-linear curve fit. Kaplan-Meier method and multivariate Cox regression was used for analysis of TD and OS. Results: The IDS and TD of AA+prednisolone showed a dose-response correlation (n = 166). Patients with high IDS had significantly longer TD and OS (p <0.001). In multivariate analysis IDS proved to be an independent marker of TD and OS. The same analysis was performed in a separate group of 81 patients receiving AA+dexamethasone treatment. The previously observed relationships were observed again between IDS and TD or OS. After combining the AA+prednisolone and AA+dexamethasone groups, analysis of the IDS composition showed that patients in the high IDS group not only used more drugs (p <0.001), but their drugs also had a higher mean DS (p = 0.001). Conclusion: The more co-drugs with high DS, the longer the duration of AA treatment and OS, emphasizing the need for careful co-medication planning in patients with mCRPC treated with AA. It is recommended that, where possible, co-medication should be modified to minimize the number of drugs with negative DS and increase the number of drugs with high DS. Our new model can presumably be adapted to other drugs and other cancer types (or other diseases).

Niraparib plus abiraterone acetate with prednisone in patients with metastatic castration-resistant prostate cancer and homologous recombination repair gene alterations: second interim analysis of the randomized phase III MAGNITUDE trial

BACKGROUND

Patients with metastatic castration-resistant prostate cancer (mCRPC) and BRCA alterations have poor outcomes. MAGNITUDE found patients with homologous recombination repair gene alterations (HRR+), particularly BRCA1/2, benefit from first-line therapy with niraparib plus abiraterone acetate and prednisone (AAP). Here we report longer follow-up from the second prespecified interim analysis (IA2).

PATIENTS AND METHODS

Patients with mCRPC were prospectively identified as HRR+ with/without BRCA1/2 alterations and randomized 1 : 1 to niraparib (200 mg orally) plus AAP (1000 mg/10 mg orally) or placebo plus AAP. At IA2, secondary endpoints [time to symptomatic progression, time to initiation of cytotoxic chemotherapy, overall survival (OS)] were assessed.

RESULTS

Overall, 212 HRR+ patients received niraparib plus AAP (BRCA1/2 subgroup, n = 113). At IA2 with 24.8 months of median follow-up in the BRCA1/2 subgroup, niraparib plus AAP significantly prolonged radiographic progression-free survival {rPFS; blinded independent central review; median rPFS 19.5 versus 10.9 months; hazard ratio (HR) = 0.55 [95% confidence interval (CI) 0.39-0.78]; nominal P = 0.0007} consistent with the first prespecified interim analysis. rPFS was also prolonged in the total HRR+ population [HR = 0.76 (95% CI 0.60-0.97); nominal P = 0.0280; median follow-up 26.8 months]. Improvements in time to symptomatic progression and time to initiation of cytotoxic chemotherapy were observed with niraparib plus AAP. In the BRCA1/2 subgroup, the analysis of OS with niraparib plus AAP demonstrated an HR of 0.88 (95% CI 0.58-1.34; nominal P = 0.5505); the prespecified inverse probability censoring weighting analysis of OS, accounting for imbalances in subsequent use of poly adenosine diphosphate-ribose polymerase inhibitors and other life-prolonging therapies, demonstrated an HR of 0.54 (95% CI 0.33-0.90; nominal P = 0.0181). No new safety signals were observed.

CONCLUSIONS

MAGNITUDE, enrolling the largest BRCA1/2 cohort in first-line mCRPC to date, demonstrated improved rPFS and other clinically relevant outcomes with niraparib plus AAP in patients with BRCA1/2-altered mCRPC, emphasizing the importance of identifying this molecular subset of patients.

Plasmatic MicroRNAs and Treatment Outcomes of Patients with Metastatic Castration-Resistant Prostate Cancer: A Hospital-Based Cohort Study and In Silico Analysis

Prostate cancer (PCa) is one of the most common malignancies among men worldwide. Inevitably, all advanced PCa patients develop metastatic castration-resistant prostate cancer (mCRPC), an aggressive phase of the disease. Treating mCRPC is challenging, and prognostic tools are needed for disease management. MicroRNA (miRNA) deregulation has been reported in PCa, constituting potential non-invasive prognostic biomarkers. As such, this study aimed to evaluate the prognostic potential of nine miRNAs in the liquid biopsies (plasma) of mCRPC patients treated with second-generation androgen receptor axis-targeted (ARAT) agents, abiraterone acetate (AbA) and enzalutamide (ENZ). Low expression levels of miR-16-5p and miR-145-5p in mCRPC patients treated with AbA were significantly associated with lower progression-free survival (PFS). The two miRNAs were the only predictors of the risk of disease progression in AbA-stratified analyses. Low miR-20a-5p levels in mCRPC patients with Gleason scores of <8 were associated with worse overall survival (OS). The transcript seems to predict the risk of death regardless of the ARAT agent. According to the in silico analyses, miR-16-5p, miR-145-5p, and miR-20a-5p seem to be implicated in several processes, namely, cell cycle, proliferation, migration, survival, metabolism, and angiogenesis, suggesting an epigenetic mechanism related to treatment outcome. These miRNAs may represent attractive prognostic tools to be used in mCRPC management, as well as a step further in the identification of new potential therapeutic targets, to use in combination with ARAT for an improved treatment outcome. Despite the promising results, real-world validation is necessary.

Trends in the Use of Second-Generation Androgen Receptor Axis Inhibitors for Metastatic Hormone-Sensitive Prostate Cancer and Clinical Factors Predicting Biological Recurrence

The advent of second-generation androgen receptor axis-targeted agents (ARATs) has revolutionized the treatment of metastatic hormone-sensitive prostate cancer (mHSPC). Biochemical recurrence-free survival (BRFS) was used to compare the efficacy of each ARAT. This multicenter retrospective study included 581 patients with newly diagnosed mHSPC who received first-line hormone therapy. The characteristics of patients treated with different ARATs were compared as well as changes in the usage of each drug over time. For BRFS, the apalutamide (Apa) and enzalutamide (Enza) groups, as well as the abiraterone acetate (Abi) and Apa/Enza groups, were compared. In addition, multivariate analysis was performed to determine predictive factors for biochemical recurrence (BCR). The use of second-generation ARATs tended to increase after May 2020. No significant difference in BRFS was found between patients receiving Apa and Enza (p = 0.490) and those receiving Abi or Apa/Enza (p = 0.906). Multivariate analysis revealed that the neutrophil-to-lymphocyte ratio (NLR) ≥ 2.76 and PSA ≥ 0.550 ng/mL were independent predictors of BCR. There were no significant differences in patient characteristics or BRFS in patients with mHSPC receiving different ARATs as first-line treatment. NLR and PSA may be prognostic factors following the first-line treatment of patients with mHSPC.

Effects of In-office Dispensing by Single-specialty Urology Practices on Management of Advanced Prostate Cancer

INTRODUCTION

We examine changes in the volume of patients with advanced prostate cancer and prescriptions for abiraterone and enzalutamide among urology practices with and without in-office dispensing.

METHODS

Using data from the National Council for Prescription Drug Programs, we identified in-office dispensing by single-specialty urology practices from 2011 to 2018. As the greatest growth in implementing dispensing occurred among large groups in 2015, outcomes were measured at the practice level in 2014 (before) and 2016 (after) for dispensing and non-dispensing practices. Outcomes included the volume of men with advanced prostate cancer managed by a practice and prescriptions for abiraterone and/or enzalutamide. Using national Medicare data, generalized linear mixed models were fit to compare the practice-level ratio of each outcome (2016 relative to 2014) adjusting for regional contextual factors.

RESULTS

In-office dispensing increased from 1% to 30% of single-specialty urology practices from 2011 to 2018, with 28 practices implementing dispensing in 2015. In 2016 compared to 2014, adjusted changes in the volume of patients with advanced prostate cancer managed by a practice were similar between non-dispensing (0.88, 95% CI 0.81-0.94) and dispensing (0.93, 95% CI 0.76-1.09) practices (P = .60). Prescriptions for abiraterone and/or enzalutamide increased in both non-dispensing (2.00, 95% CI 1.58-2.41) and dispensing (8.99, 95% CI 4.51-13.47) practices (P < .01).

CONCLUSIONS

In-office dispensing is increasingly common in urology practices. This emerging model is not associated with changes in patient volume but is associated with increased prescriptions for abiraterone and enzalutamide.

Adapting to hormone-therapy resistance for adopting the right therapeutic strategy in advanced prostate cancer

INTRODUCTION

The androgen/androgen receptor (AR) axis represents a key driver of treatment resistance in prostate cancer (PCa) patients receiving androgen deprivation therapy (ADT) and targeted agents, and a deeper comprehension of resistance mechanisms is fundamental to adopt effective therapeutic strategies.

AREAS COVERED

We review the mechanisms of primary or secondary resistance to hormone therapy (HT) in PCa, especially focusing on available data and emerging evidence.

EXPERT OPINION

First- and second-generation HT resistance has been associated with several AR-dependent and AR-independent mechanisms, ranging from the amplification of the AR gene locus to somatic AR mutations and the intratumoral synthesis of androgens from adrenal steroids and cholesterol. As reported in the current review, the development of novel and effective treatments is needed to personalize anticancer therapies in this setting and to finally improve clinical outcomes in patients with HT resistant disease.

Visceral Metastasis Predicts Response to New Hormonal Agents in Metastatic Castration-Sensitive Prostate Cancer

Visceral metastasis (VM) and a higher number of bone metastasis generally define high volume/risk in patients with metastatic castration-sensitive prostate cancer (mCSPC). Subgroup analysis of pivotal trials did not show a clear benefit of second-generation non-steroidal anti-androgens (NSAAs) in patients with VM. However, subgroup analysis of the trial assessing abiraterone acetate, a CYP 17 inhibitor, plus prednisone (AAP) showed an improved overall survival (OS) in patients with mCSPC with VM. We searched MEDLINE, Web of Science, and congress abstracts for the phase III randomized controlled trials of second-generation NSAAs and AAP in patients with mCSPC. In this pooled analysis, we included 6485 patients from the 6 phase III trials. The rate of patients with VM was 15.2%. Interestingly, in contrast to NSAAs, AAP seems to be effective in improving OS among patients with VM (hazard ratio, HR: 0.89, 95% CI, 0.72-1.11, P = .30 for second-generation NSAAs; HR: 0.58, 95% CI, 0.40-0.84, P = .004 for AAP). In contrast, both second-generation NSAAs (HR: 0.63, 95% CI, 0.57-0.70, P < .001) and AAP (HR: 0.68, 95% CI, 0.57-0.81, P < .001) improved OS in patients without VM. In this pooled analysis, we demonstrate that while AAP provided an OS improvement in patients with VM, second-generation NSAAs did not demonstrate a similar OS benefit in this population.

Niraparib with Abiraterone Acetate and Prednisone for Metastatic Castration-Resistant Prostate Cancer: Phase II QUEST Study Results

Niraparib (NIRA) is a highly selective inhibitor of poly (adenosine diphosphate-ribose) polymerase, PARP1 and PARP2, which play a role in DNA repair. The phase II QUEST study evaluated NIRA combinations in patients with metastatic castration-resistant prostate cancer who were positive for homologous recombination repair gene alterations and had progressed on 1 prior line of novel androgen receptor-targeted therapy. Results from the combination of NIRA with abiraterone acetate plus prednisone, which disrupts androgen axis signaling through inhibition of CYP17, showed promising efficacy and a manageable safety profile in this patient population.

Dynamic assessment of serum chromogranin A and treatment response with abiraterone acetate in metastatic castration-resistant prostate cancer

OBJECTIVE

Elevated serum chromogranin A (CGA) is associated with intrinsic or treatment-related neuroendocrine differentiation (NED) in men with metastatic castration-resistant prostate cancer (mCRPC). Fluctuations in serum CGA during treatment of mCRPC have had conflicting results. We analyzed the impact of (i) rising serum CGA and (ii) baseline CGA/PSA ratio during treatment to identify associations with abiraterone acetate (AA) therapy.

METHODS

Between June 2013 and August 2015, 92 men with mCRPC were enrolled in a prospective trial with uniform serum CGA processing performed before initiating abiraterone acetate/prednisone (AA/P) and serially after 12 weeks of AA/P treatments. Serum CGA was measured using a homogenous automated immunofluorescent assay. Patients receiving proton pump inhibitors or with abnormal renal function were excluded due to possible false elevations of serum CGA (n = 21 excluded), therefore 71 patients were analyzed. All patients underwent a composite response assessment at 12-weeks. Kaplan-Meier estimates and Cox Regression models were used to calculate the association with time-to-treatment failure analyses and overall survival.

RESULTS

An increase in chromogranin was associated with a lower risk of treatment failure (hazard ratio [HR]: 0.52, p = 0.0181). The median CGA/PSA ratio was 7.8 (2.6-16.0) and an elevated pretreatment CGA/PSA ratio above the median was associated with a lower risk of treatment failure (HR: 0.54 p value = 0.0185). An increase in CGA was not found to be associated with OS (HR: 0.71, 95% CI: 0.42-1.21, p = 0.207). An elevated baseline CGA/PSA ratio was not associated with OS (HR: 0.62, 95% CI: 0.37-1.03, p = 0.062). An increase in PSA after 12 weeks of treatment was associated with an increased risk of treatment failure (HR: 4.14, CI: 2.21-7.73, p = < 0.0001) and worse OS (HR: 2.93, CI: 1.57-4.45, p = < 0.0001).

CONCLUSIONS

We show that an increasing chromogranin on AA/P and an elevated baseline CGA/PSA in patients with mCRPC were associated with a favorable response to AA/P with no changes in survival. There may be limited clinical utility in serum CGA testing to evaluate for lethal NED as AA/P did not induce lethal NED in this cohort. This highlights that not all patients with an increasing CGA have a worse OS.

Clinical outcomes of volume of disease on patients receiving enzalutamide versus abiraterone acetate plus prednisone as first-line therapy for metastatic castration-resistant prostate cancer

Background

Androgen receptor signaling inhibitors (ARSis) abiraterone acetate (AA) plus prednisone and enzalutamide (Enza), are currently the most administered first-line treatments for metastatic castration-resistant prostate cancer (mCRPC). AA and Enza have shown similar overall survival (OS) benefits and there is no consensus upon the best option for mCRPC first-line treatment. Volume of disease may represent a useful biomarker to predict response to therapy in such patients.

Objectives

In this study, we seek to evaluate the impact of volume of disease on patients treated with first-line AA versus Enza for mCRPC.

Design and methods

We retrospectively evaluated a cohort of consecutive patients with mCRPC categorized by volume of disease [high volume (HV) or low volume (LV) per E3805 criteria] at ARSi onset and treatment type (AA or Enza), assessing OS and radiographic progression-free survival (rPFS), from therapy start, as co-primary endpoints.

Results

Of the 420 patients selected, 170 (40.5%) had LV and received AA (LV/AA), 76 (18.1%) LV and had Enza (LV/Enza), 124 (29.5%) HV and were given AA (HV/AA), and 50 (11.9%) HV and received Enza (HV/Enza). Among patients with LV, OS was significantly longer when treated with Enza [57.2 months; 95% confidence interval (CI): 52.1-62.2 months] versus AA (51.6 months; 95% CI, 42.6-60.6 months; p = 0.003). Consistently, those with LV receiving Enza showed increased rPFS (40.3 months; 95 CI, 25.0-55.7 months) than those having AA (22.0 months; 95% CI, 18.1-26.0 months; p = 0.004). No significant difference in OS or rPFS was observed in those with HV treated with AA versus Enza (p = 0.51 and p = 0.73, respectively). In multivariate analysis of patients with LV, treatment with Enza was independently associated with better prognosis than AA.

Conclusion

Within the intrinsic limitations of a retrospective design and small population, our report suggests that volume of disease could be a useful predictive biomarker for patients starting first-line ARSi for mCRPC.

Abigene, a Prospective, Multicentric Study of Abiraterone Acetate Pharmacogenetics in Metastatic Castration-Resistant Prostate Cancer

Abiraterone acetate (AA) is the first-in-class of drugs belonging to the second-generation of agents inhibiting androgen neosynthesis in advanced prostate cancer. A cumulative experience attests that germinal gene polymorphisms may play a role in the prediction of anticancer agent pharmacodynamics variability. In the present prospective, multicentric study, gene polymorphisms of CYP17A1 (AA direct target) and the androgen transporter genes SLCO2B1 and SLCO1B3 (potential modulators of AA activity) were confronted with AA pharmacodynamics (treatment response and toxicity) in a group of 137 advanced prostate cancer patients treated in the first line by AA. The median follow-up was 56.3 months (95% CI [52.5-61]). From multivariate analysis, rs2486758 C/C (CYP17A1) and PSA (≥10 ng/mL) were associated with a shorter 3-year biological PFS (HR = 4.05, IC95% [1.46-11.22]; p = 0.007 and HR = 2.08, IC95% [1.31-3.30]; p = 0.002, respectively). From a multivariate analysis, the rs743572 (CYP17A1) and performance status were independently associated with significant toxicity (OR = 3.78 (IC95% [1.42-9.75]; p = 0.006 and OR = 4.54; IC95% [1.46-13.61]; p = 0.007, respectively). Host genome characteristics may help to predict AA treatment efficacy and identify patients at risk for toxicity.

Body composition parameters were associated with response to abiraterone acetate and prognosis in patients with metastatic castration-resistant prostate cancer

OBJECTIVE

To investigate the predictive value of body composition parameters for biochemical response to abiraterone acetate (AA) in metastatic castration-resistant prostate cancer (mCRPC) patients with prior chemohormonal therapy.

METHODS

We retrospectively evaluated the clinicopathologic information of 132 mCRPC cases receiving AA treatment after chemohormonal therapy at hormone-sensitive stage from July 2018 to June 2021. All patients were divided into AA responders and non-responders according to the biochemical response to AA (prostate-specific antigen (PSA) reduction ≥50% than pretreatment). Multivariate Logistic analysis was used to determine the independent predictors and develop predictive model of biochemical response to AA. Cox regression analysis was utilized to investigate the prognostic factors for time to biochemical progression (TTBP), radiological progression-free survival (rPFS), failure-free survival (FFS), and overall survival (OS) after AA treatment.

RESULTS

There were 57 AA responders and 75 AA non-responders. Periprostatic fat area/prostate area (PPFA/PA) was decreased and skeletal muscle index (SMI) was increased in AA responders compared with AA non-responders. Multivariable logistic analysis demonstrated that ADT duration ≥12 months, bone metastasis only, high SMI and low PPFA/PA were independent predictors of biochemical response to AA treatment. The FFS, TTBP, rPFS, and OS of patients with lower SMI or higher PPFA/PA was decreased compared with that of patients with higher SMI or lower PPFA/PA, respectively. Combining SMI, PPFA/PA, ADT duration and metastatic sites performed well in differentiating AA responders from non-responders.

CONCLUSIONS

High SMI and low PPFA/PA could predict biochemical response to AA treatment and preferable prognosis in mCRPC patients with prior chemohormonal therapy at hormone-sensitive stage.

Enzalutamide or Abiraterone Acetate With Prednisone in the Treatment of Metastatic Castration-resistant Prostate Cancer in Real-life Clinical Practice: A Long-term Single Institution Experience

BACKGROUND/AIM

Enzalutamide (ENZ) and abiraterone acetate with prednisone (AAP) represent novel hormonal therapies used in the treatment of metastatic castration-resistant prostate cancer (mCRPC). The aim of the study was to assess the long-term outcome of mCRPC patients treated with ENZ or AAP in real-life clinical practice.

PATIENTS AND METHODS

The outcomes of 337 mCRPC patients treated with ENZ or AAP were retrospectively analysed.

RESULTS

Median radiographic progression-free (rPFS) and overall survival (OS) of patients treated in the first line (pre-chemotherapy) was 13.89 (95% CI=12.40-16.80) and 31.02 (95% CI=24.27-37.44) months vs. 10.97 (95% CI=8.97-14.82) and 26.57 (95% CI=15.97-33.92) months for those treated in the second line (post-chemotherapy). We found inferior survival for patients with synchronous metastases, high Gleason score (GS) and visceral metastases.

CONCLUSION

The efficacy of both ENZ and AAP in mCRPC patients is herein confirmed. Synchronous metastases, high GS and visceral metastases were identified as significant adverse prognostic factors.

miR-143 mediates abiraterone acetate resistance by regulating the JNK/Bcl-2 signaling pathway in prostate cancer

Background: miR-143 is known to be downregulated in various cancer cells and tumors and generally plays a tumor-suppressor role. miR-143. However, the role of miR-143 in the mediation of the sensitivity of prostate cancer cells to abiraterone acetate remains unrevealed. Methods: The expression levels of miRNAs were determined by miRNA microarray and quantitative real-time PCR (qRT-PCR). The protein levels were assessed by Western blot assay. Cell viability and apoptosis were respectively measured by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Results: We identified that miR-143 was significantly downregulated in PC3-AbiR cells compared to PC3 cells. Overexpression of miR-143 promoted PC-AbiR sensitivity to abiraterone acetate in vitro and in vivo. We also revealed that miR-143 upregulation inhibited p-JNK (c-Jun N-terminal kinases) and increased p-Bcl2 (B-cell lymphoma 2), contributing to abiraterone acetate-induced apoptosis in PC3-AbiR cells. Finally, we showed that the combination of miR-143 and abiraterone acetate exerted the most profound tumor inhibition effect and prolonged the mice survival rate in PC3-AbiR tumor-bearing mice. Conclusion: Upregulation of miR-143 may serve as a new strategy to enhance the therapeutical effect of abiraterone acetate on prostate cancer patients who are resistant to abiraterone acetate.

Prognostic role of pan-immune-inflammation value in patients with metastatic castration-resistant prostate cancer treated with androgen receptor-signaling inhibitors

AIM

To assess the prognostic effect of pan-immune inflammation value (PIV) in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate (AA) or enzalutamide.

METHODS

Patients with mCRPC treated with AA or enzalutamide between January 2010 and June 2021 were included in this study. The most recently examined complete blood count values in the 1-month period before treatment were used for calculating PIV. The relationship between overall survival (OS) and PIV was evaluated by multivariate analysis. By using PIV and lactate dehydrogenase (LDH) levels which had shown survival effect at multivariate analysis, PIV-LDH combined score was established.

RESULTS

A total of 114 patients were included in this study. At the median follow-up of 34.6 months (95% confidence interval [CI]: 32.4-36.8), the median OS was 21 months (95% CI: 17.6-21.3). The median OS in the low-PIV group was significantly higher than in the high-PIV group (34.4 months (95% CI: 21.3-47.5) vs. 14.3 months (95% CI: 10.0-18.7), p < 0.001). In the multivariate analysis for OS, high PIV (hazard ratio [HR]: 1.86, 95% CI: 1.11-3.13, p = 0.018) and LDH value 1.5 times the upper limit of normal and above (HR: 3.65 95%, CI: 1.86-7.16, p < 0.001) were associated with shorter OS. When survival analysis was performed according to the PIV-LDH combined score, the median OS was 34.4 months (95% CI: 22.2-46.6) in the low-risk group, 17.7 months (95% CI: 11.7-23.6) in the intermediate-risk group, and 8.4 months (95% CI: 5.1-11.7) in the high-risk group (p < 0.001). The C-index of the combined PIV-LDH score was higher than the C-index of PIV (0.65 vs. 0.61).

CONCLUSION

In this study, we demonstrated that PIV was an independent prognostic factor for OS in patients with mCRPC treated with AA or enzalutamide. Additionally, PIV-LDH combined score may be considered a promising composite peripheral blood-based biomarker to predict OS in those patients.

Factors influencing survival in metastatic castration resistant prostate cancer therapy

INTRODUCTION

The number of patients with metastatic castration resistant prostate cancer (mCRPC) is expecting to increase due to the long-life expectancy of those with advanced disease who are also more commonly diagnosed today because of stage migration. Several compounds are available for treating these patients.

AREAS COVERED

We reviewed currently available treatments for mCRPC, their mechanism of action and resistance and we explored possible predictors of treatment success useful to predict survival in mCRPC patients.

EXPERT OPINION

A combination of molecular, clinical, pathological, and imaging features is necessary to correctly estimate patients' risk of death. The combination of these biomarkers may allow clinicians to tailor treatments based on cancer history and patients' features. The search of predictive biomarkers remains an unmet medical need for most patients with mCRPC.

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.

Open-Label, Phase I, Pharmacokinetic Studies in Healthy Chinese Subjects to Evaluate the Bioequivalence and Food Effect of a Novel Formulation of Abiraterone Acetate Tablets

Purpose

Abiraterone acetate tablets (I)(N-AbA) is a novel tablet co-formulated with the absorption enhancer sodium N-(8-[2-hydroxybenzoyl] amino) caprylate (SNAC). This study aimed to compare the pharmacokinetics, bioequivalence, safety, and food effects of N-AbA with the reference ZYTIGA^® (R-AbA) in healthy Chinese male subjects.

Patients and Methods

This study was conducted in three parts. Part I was an open, dose-escalation trial conducted in 16 Chinese healthy males; Part II was a randomized, open-label, 2 × 4 crossover, single-dose bioequivalence trial conducted in 36 subjects; Part III was a randomized, 3 × 3 crossover trial conducted on 24 volunteers to investigate the effect of food on the pharmacokinetics of N-AbA.

Results

The exposure (AUC_0-∞) and maximum concentration (C_max) of abiraterone and excipient SNAC were linear in the range of 75–450 mg dose. The bioavailability of N-AbA 300 mg was equivalent to that of R-AbA 1000 mg. The drug exposure of prednisone and prednisolone was not affected by SNAC co-administration. The C_max of orally administered abiraterone as R-AbA in a modified fed state was 5.9 times and AUC_0-∞ was 4.3 times, respectively, higher than those in of orally administered abiraterone as N-AbA in a high-fat diet. The C_max and AUC_0-∞ of orally administered abiraterone as N-AbA on a high-fat diet were 2.2 times and 2 times, respectively, higher than those on a fasting state. All adverse events reported in the three parts of the study were grade 1 or 2, and no serious adverse events were reported.

Conclusion

These three Phase I trials showed that N-AbA and excipient SNAC had excellent linear pharmacokinetic characteristics. A single dose of N-AbA 300 mg was bioequivalent to R-AbA 1000 mg in healthy subjects under fasting conditions. Meanwhile, SNAC had no effect on the pharmacokinetics of prednisone and prednisolone. The effect of food on N-AbA was significantly lower than that on R-AbA.

Role of Silica Intrawall Microporosity on Abiraterone Acetate Solubilization and In Vivo Oral Absorption

SBA-15 mesoporous silica (MPS) has been widely used in oral drug delivery; however, it has not been utilized for solidifying lipid-based formulations, and the impact of their characteristic intrawall microporosity remains largely unexplored. Here, we derive the impact of the MPS microporosity on the in vitro solubilization and in vivo oral pharmacokinetics of the prostate cancer drug abiraterone acetate (AbA) when coencapsulated along with medium chain lipids into the pores. AbA in lipid (at 80% equilibrium solubility) was imbibed within a range of MPS particles (with comparable morphology and mesoporous structure but contrasting microporosity ranging from 0-247 m²/g), and their solid-state properties were characterized. Drug solubilization studies during in vitro lipolysis revealed that microporosity was the key factor in facilitating AbA solubilization by increasing the surface area available for drug-lipid diffusion. Interestingly, microporosity hindered hydrolysis of AbA to its active metabolite, abiraterone (Ab), under simulated intestinal conditions. This unique relationship between microporosity and AbA/Ab aqueous solubilization behavior was hypothesized to have significant implications on the subsequent bioavailability of the active metabolite. In vivo oral pharmacokinetics studies in male Sprague-Dawley rats revealed that MPS with moderate microporosity attained the highest relative bioavailability, while poor in vitro-in vivo correlations (IVIVC) existed between in vitro drug solubilization during lipolysis and in vivo AUC. Despite this, a reasonable IVIVC was established between the in vitro solubilization and in vivo C_max, providing evidence for an association between silica microporosity and oral drug absorption.

Abiraterone acetate versus nonsteroidal antiandrogen with androgen deprivation therapy for high-risk metastatic hormone-sensitive prostate cancer

BACKGROUND

Although prostate cancer is a very common form of malignancy in men, the clinical significance of androgen deprivation therapy (ADT) with abiraterone acetate versus the nonsteroidal antiandrogen bicalutamide has not yet been verified in patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC). The present study was designed to initiate this verification in real-world Japanese clinical practice.

METHODS

We retrospectively analyzed the records of 312 patients with high-risk mHSPC based on LATITUDE criteria and had received ADT with bicalutamide (n = 212) or abiraterone acetate (n = 100) between September 2015 and December 2020. Bicalutamide was given at 80 mg daily and abiraterone was given at 1000 mg daily as four 250-mg tablets plus prednisolone (5-10 mg daily). Overall survival (OS), cancer-specific survival (CSS), and time to castration-resistant prostate cancer (CRPC) were compared. The prognostic factor for time to CRPC was analyzed by Cox proportional hazard model.

RESULTS

Patients in the bicalutamide group were older, and more of them had poor performance status (≧2), than in the abiraterone group. Impaired liver function was noted in 2% of the bicalutamide group and 16% of the abiraterone group (p < 0.001). Median follow-up was 22.5 months for bicalutamide and 17 months for abiraterone (p < 0.001). Two-year OS and CSS for bicalutamide versus abiraterone was 77.8% versus 79.5% (p = 0.793) and 81.1% versus 82.5% (p = 0.698), respectively. Median time to CRPC was significantly longer in the abiraterone group than in the bicalutamide group (NA vs. 13 months, p < 0.001). In multivariate analysis, Gleason score ≧9, high alkaline phosphatase, high lactate dehydrogenase, liver metastasis, and bicalutamide were independent prognostic risk factors for time to CRPC. Abiraterone prolonged the time to CRPC in patients with each of these prognostic factors.

CONCLUSIONS

Despite limitations regarding the time-dependent bias, ADT with abiraterone acetate significantly prolonged the time to CRPC compared to bicalutamide in patients with high-risk mHSPC. However, further study with longer follow-up is needed.

Prognostic Impact of Sarcopenia in Patients with Metastatic Hormone-Sensitive Prostate Cancer

The clinical value of sarcopenia has not been determined yet in metastatic hormone-sensitive prostate cancer (mHSPC). We retrospectively evaluated data of 70 consecutive patients with mHSPC receiving treatment with either early docetaxel (n = 42) or abiraterone acetate (n = 28) between July 2018 and April 2021. Skeletal muscle index was calculated from cross-sectional areas of skeletal muscle on baseline computed tomography (CT), defining sarcopenia as a skeletal muscle index of ≤52.4 cm²/m². Failure-free survival (FFS), radiographic progression-free survival, and time to prostate-specific antigen (PSA) progression were estimated using the Kaplan-Meier method, and differences in survival probability were compared using the log-rank test. Cox proportional hazards regression analysis was conducted to identify the predictors of clinical outcomes. Patients with sarcopenia (n = 47) had shorter FFS than those without sarcopenia (n = 23) (median, 20.1 months vs. not reached; log-rank p < 0.001). Sarcopenia was independently associated with shorter FFS (hazard ratio (HR), 6.69; 95% confidence interval (CI), 1.57-28.49; p = 0.010) and time to PSA progression (HR, 12.91; 95% CI, 1.08-153.85; p = 0.043). In conclusion, sarcopenia is an independent prognostic factor for poor FFS and time to PSA progression in patients with mHSPC who receive early docetaxel or abiraterone acetate treatment.

Dose Finding and Food Effect Studies of a Novel Abiraterone Acetate Formulation for Oral Suspension in Comparison to a Reference Formulation in Healthy Male Subjects

Currently approved formulations of the androgen synthesis inhibitor abiraterone acetate (AA) consist of multiple tablets administered daily in a fasted state. Removing the food effect and switching to a suspension formulation is expected to improve the pharmacokinetic profile and facilitate drug administration for patients with late-stage prostate cancer. Two four-sequence, four-period randomized crossover investigations were undertaken to establish the pharmacokinetic profiles of single doses of commercially available Zytiga^®, as the reference AA (R-AA), and a novel tablet for oral suspension (TOS). Four single doses of TOS (from 62.5 to 250 mg) were compared in study C01, and two single doses each of TOS (250 mg) and R-AA (1000 mg) were compared under fasted and fed (modified fasted for R-AA) conditions in C02. Plasma concentrations of abiraterone over time were measured, and pharmacokinetic parameters were calculated. Each doubling of the dose of TOS was associated with a greater than 3-fold increase in exposure. A single dose of TOS (250 mg) exhibited similar exposure over 24 h, whether given fasted (625 ng × h/mL) or fed (485 ng × h/mL). A single dose of TOS (250 mg) was associated with higher (fasted, p = 0.028) or equivalent exposure (fed) compared to 1000 mg R-AA fasted (532 ng × h/mL). Substantially higher exposures were seen with 1000 mg R-AA under modified fasted conditions compared to TOS, irrespective of prandial status (p < 0.001). TOS was generally safe and well tolerated in the study. A 250 mg dose of a novel AA formulation for oral suspension demonstrated bioequivalence to 1000 mg R-AA under fasted conditions. This novel TOS formulation also addresses some of the limitations of current AA treatment, including low bioavailability, high variability in systemic exposure and a large food effect. It may offer an alternative for patients with dysphagia or discomfort with swallowing large pills.

RNA Biomarkers as a Response Measure for Survival in Patients with Metastatic Castration-Resistant Prostate Cancer

Treatment evaluation in metastatic castration-resistant prostate cancer is challenging. There is an urgent need for biomarkers to discriminate short-term survivors from long-term survivors, shortly after treatment initiation. Thereto, the added value of early RNA biomarkers on predicting progression-free survival (PFS) and overall survival (OS) were explored. The RNA biomarkers: KLK3 mRNA, miR-375, miR-3687, and NAALADL2-AS2 were measured in 93 patients with mCRPC, before and 1 month after start of first-line abiraterone acetate or enzalutamide treatment, in two prospective clinical trials. The added value of the biomarkers to standard clinical parameters in predicting PFS and OS was tested by Harell's C-index. To test whether the biomarkers were independent markers of PFS and OS, multivariate Cox regression was used. The best prediction model for PFS and OS was formed by adding miR-375 and KLK3 (at baseline and 1 month) to standard clinical parameters. Baseline miR-375 and detectable KLK3 after 1 month of therapy were independently related to shorter PFS, which was not observed for OS. In conclusion, the addition of KLK3 and miR-375 (at baseline and 1 month) to standard clinical parameters resulted in the best prediction model for survival assessment.

Highlighting the Place of Metastasis-Directed Therapy in Isolated Liver Metastases in Prostate Cancer: A Case Report

Metastatic prostate cancer remains a challenge for clinicians. Metastases involve mainly the bone compartment and can manifest as oligometastatic disease. In this setting, the role of metastasis-directed therapies (MDT) including surgery and/or stereotactic body radiotherapy is currently evaluated. Visceral metastases are less common and have very poor prognosis in mPC. Whether treating isolated visceral metastases such as liver metastases with MDT could increase the prognosis remains unknown. We report the management of a prostate cancer patient who progressed on androgen deprivation therapy with apparition of two liver metastases. We describe the feasibility of combining MDT with abiraterone acetate and prednisone in a patient with metastatic castration-resistant prostate cancer. MDT allowed the interruption of abiraterone acetate, preventing cumulative toxicity of this agent.

Useful predictors of progression-free survival for Japanese patients with LATITUDE-high-risk metastatic castration-sensitive prostate cancer who received upfront abiraterone acetate

Objective

Recently, hormonal therapy using abiraterone acetate, a second‐generation androgen receptor axis‐targeted agent, was reported to improve overall survival and progression‐free survival in men with LATITUDE‐high‐risk metastatic castration‐sensitive prostate cancer. This observational multicenter study aimed to assess the efficacy of upfront abiraterone acetate in Japanese patients with LATITUDE‐high‐risk metastatic castration‐sensitive prostate cancer.

Methods

The present study included 112 Japanese patients with LATITUDE‐high‐risk metastatic castration‐sensitive prostate cancer who received upfront abiraterone acetate at four institutions belonging to the Tokai Urologic Oncology Research Seminar group, between January 2018 and September 2020. Progression‐free survival and overall survival were assessed, and Cox regression analyses were carried out to evaluate the prognostic significance of upfront abiraterone acetate for progression‐free survival.

Results

Within a median follow‐up period of 13 months, the progression‐free survival and overall survival rates were 76.8% and 89.3%, respectively. Both univariate and multivariable Cox regression analyses showed that the presence of Gleason pattern 5, performance status and hemoglobin were independent predictors of progression‐free survival. The patients were subsequently divided into three groups as follows: group 1, 17 patients negative for these three independent progression‐free survival predictors; group 2, 49 patients with one positive independent progression‐free survival predictor; and group 3, 45 patients with two or three independent progression‐free survival predictors. Progression‐free survival was significantly different among these three groups (P < 0.001).

Conclusion

Upfront abiraterone acetate might provide satisfactory outcomes for Japanese patients with LATITUDE‐high‐risk metastatic castration‐sensitive prostate cancer. Gleason pattern 5, performance status and hemoglobin are potential predictors of progression‐free survival in Japanese patients with LATITUDE‐high‐risk metastatic castration‐sensitive prostate cancer who received upfront abiraterone acetate.

High IL-23+ cells infiltration correlates with worse clinical outcomes and abiraterone effectiveness in patients with prostate cancer

Individualized treatment of prostate cancer depends on an accurate stratification of patients who are sensitive to various treatments. Interleukin-23 (IL-23) was reported to play a significant role in prostate cancer. Here, we aimed to explore the clinical value of IL-23-secreting (IL-23+) cells in prostate cancer patients. We evaluated interleukin-23A (IL-23A) expression in The Cancer Genome Atlas database and retrospectively enrolled 179 treatment-naïve metastatic prostate cancer patients diagnosed in our institute between June 2012 and December 2014. IL-23⁺ cells were stained and evaluated via immunohistochemistry. Further, survival and multivariate Cox regression analyses were conducted to explore the prognostic value of IL-23⁺ cells. We found that IL-23A expression correlated with disease progression, while IL-23⁺ cells were clearly stained within prostate cancer tissue. Patients with higher Gleason scores and multiple metastatic lesions tended to have more IL-23⁺ cell infiltration. Further analyses showed that patients with higher levels of IL-23⁺ cells had significantly worse overall survival (hazard ratio [HR] = 2.996, 95% confidence interval [95% CI]: 1.812–4.955; P = 0.001) and a higher risk of developing castration resistance (HR = 2.725, 95% CI: 1.865–3.981; P = 0.001). Moreover, subgroup analyses showed that when patients progressed to a castration-resistant status, the prognostic value of IL-23⁺ cells was observed only in patients treated with abiraterone instead of docetaxel. Therefore, we showed that high IL-23⁺ cell infiltration is an independent prognosticator in patients with metastatic prostate cancer. IL-23⁺ cell infiltration may correlate with abiraterone effectiveness in castration-resistant prostate cancer patients.

Medication adherence among patients with advanced prostate cancer using oral therapies

Aims: In light of the extended overall survival and improved quality of life provided by advanced prostate cancer (PC) oral therapies, this study aimed to describe treatment adherence to advanced PC oral therapies and evaluate associated patient characteristics and subsequent healthcare resource utilization (HRU). Patients & methods: Patients with advanced PC initiating apalutamide, enzalutamide or abiraterone acetate were identified from administrative data (October 1, 2014-September 30, 2019). Adherence and persistence at six months postinitiation were used to evaluate patient factors and HRU. Results: Aged ≥75 years, Black race, chemotherapy use and higher pharmacy paid amounts were associated with poor adherence/persistence, which translated to higher HRU. Conclusions: Strategies to increase adherence and persistence may improve patient outcomes and associated HRU.

A Case Report of Metastatic Castration-Resistant Prostate Cancer Harboring a PTEN Loss

The treatment landscape of metastatic castration-resistant prostate cancer (mCRPC) has dramatically improved over the last decade; however, patients with visceral metastases are still faced with poor outcomes. Phosphatase and tensin homolog (PTEN) loss is observed in 40%–60% of mCRPC patients and is also associated with a poor prognosis. Several PI3K/AKT/mTOR pathway inhibitors have been studied, with disappointing anti-tumor activity. Here, we present a case of a patient with heavily treated mCRPC who had a modest tumor response to concurrent carboplatin, abiraterone acetate/prednisone, and liver-directed radiation therapy. We discuss the potential rationale supporting the use of this combination therapy and its safety in mCRPC. While the underlying basic mechanism of our patient’s anti-tumor response remains uncertain, we suggest that further prospective studies are warranted to evaluate whether this combination therapy is effective in this population of patients with pre-treated mCRPC and PTEN loss.

Real-world outcomes of second novel hormonal therapy or radium-223 following first novel hormonal therapy for mCRPC

Aim: To evaluate real-world clinical outcomes of radium-223 or alternative novel hormonal therapy (NHT) following first-line NHT for metastatic castration-resistant prostate cancer (mCRPC). Patients & methods: Retrospective analysis of the US Flatiron database (ClinicalTrials.gov identifier: NCT03896984). Results: In the radium-223 cohort (n = 120) versus the alternative NHT cohort (n = 226), proportionally more patients had prior symptomatic skeletal events and bone-only metastases, and first-line NHT duration was shorter. Following second-line therapy, 49 versus 39% of patients received subsequent life-prolonging therapy; of these, 47 versus 76% received taxane. Median overall survival was 10.8 versus 11.2 months. Conclusion: Real-world patients with mCRPC had similar median overall survival following second-line radium-223 or alternative NHT after first-line NHT. Many patients received subsequent therapy, with less taxane use after radium-223.

Efficacy and Safety of Abiraterone Acetate and Enzalutamide for the Treatment of Metastatic Castration-Resistant Prostate Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

The androgen receptor-targeting drugs abiraterone acetate and enzalutamide have shown positive results as treatments for metastatic castration-resistant prostate cancer (mCRPC). Therefore, a meta-analysis was conducted to compare the efficacy and safety of abiraterone acetate and enzalutamide in patients with mCRPC.

METHODS

We retrieved relevant articles from PubMed, Cochrane, and EMBASE published before December 31, 2020. Eleven articles were initially selected, and four phase III, double-blind, randomized controlled trials of abiraterone acetate and enzalutamide that involved 5199 patients with mCRPC were included. The end points were time to prostate-specific antigen progression (TTPP), according to the prostate-specific antigen working group criteria; overall survival (OS); and radiographic progression-free survival (rPFS).

RESULTS

Four randomized, controlled clinical trials involving 5199 patients were included in this study. The results of the meta-analysis showed that compared with placebo alone, abiraterone significantly improved OS (HR=0.69, 95% CI: 0.60-0.8, P<0.00001), rPFS (HR=0.64, 95% CI: 0.57-0.71, P < 0.00001), and TTPP (HR=0.52, 95% CI: 0.45-0.59, P < 0.00001) in patients with mCRPC. Compared with placebo, enzalutamide significantly improved OS (HR=0.67, 95% CI: 0.59-0.75, P<0.00001), rPFS (HR=0.33, 95% CI: 0.29-0.37, P< 0.00001), and TTPP (HR=0.19, 95% CI: 0.17-0.22, P < 0.00001). An indirect comparison was performed to compare the efficacy of abiraterone and enzalutamide. The results showed that there was no significant difference between abiraterone and enzalutamide with regard to improving the OS of patients with mCRPC (HR=1.03, 95% CI: 0.854-1.242). Enzalutamide was superior to abiraterone with regard to improving rPFS in patients with mCRPC (HR=0.516, 95% CI: 0.438-0.608). With regard to improving TTPP, the efficacy of enzalutamide was better than that of abiraterone (HR=0.365, 95% CI: 0.303-0.441). In sAE, there was no difference between abiraterone and enzalutamide (P=0.21, I2 = 38%).

CONCLUSIONS

Compared with placebo, both abiraterone and enzalutamide significantly prolonged OS, rPFS, and TTPP in patients with mCRPC. There was no difference in safety between abiraterone and enzalutamide. In addition, enzalutamide had better efficacy than abiraterone with regard to improving rPFS and TTPP but not OS, but the level of evidence was low. Therefore, a large direct comparison trial is needed to compare the efficacy of the two drugs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, identifier (CRD42021226808).

The effect of chemotherapy on the exposure-response relation of abiraterone in metastatic castration-resistant prostate cancer

Aims

To assess whether the exposure–response relation for abiraterone is different in pre‐chemotherapy patients compared to post‐chemotherapy patients with metastatic castration‐resistant prostate cancer (mCRPC).

Methods

Data were collected from three clinical studies in mCRPC patients treated with abiraterone acetate. Cox regression analysis was used to determine the relation between abiraterone exposure and survival (progression‐free survival [PFS] and overall survival [OS]). An interaction term was used to test whether chemotherapy pretreatment was an effect modifier. To investigate the effect of the previously defined exposure threshold of 8.4 ng/mL on survival, Kaplan–Meier analysis was used.

Results

In total, 98 mCRPC patients were included, of which 78 were pre‐chemotherapy and 20 were post‐chemotherapy patients. Chemotherapy pretreatment in mCRPC setting appears to be an effect modifier. In pre‐chemotherapy patients, no significant association between abiraterone exposure and survival was observed (HR 0.68 [95% CI 0.42–1.10], P = .12 and HR 0.85 [95% CI 0.46–1.60], P = .61, PFS and OS, respectively) and no longer survival was seen for patients with an abiraterone exposure above the predefined threshold. In contrast, a significant association was seen in post‐chemotherapy patients (HR 0.30 [95% CI 0.12–0.74], P = .01 and HR 0.38 [95% CI 0.18–0.82] P = .01, PFS and OS, respectively), with an increased survival when exposed above this threshold.

Conclusion

Chemotherapy pretreatment in mCRPC setting modifies the abiraterone exposure–response relation. No relation between abiraterone exposure and survival was seen for pre‐chemotherapy patients. Therefore, potentially lower doses can be used in this setting to prevent overtreatment and reduce financial toxicity.

A prospective trial of abiraterone acetate plus prednisone in Black and White men with metastatic castrate-resistant prostate cancer

BACKGROUND

Retrospective analyses of randomized trials suggest that Black men with metastatic castration-resistant prostate cancer (mCRPC) have longer survival than White men. The authors conducted a prospective study of abiraterone acetate plus prednisone to explore outcomes by race.

METHODS

This race-stratified, multicenter study estimated radiographic progression-free survival (rPFS) in Black and White men with mCRPC. Secondary end points included prostate-specific antigen (PSA) kinetics, overall survival (OS), and safety. Exploratory analysis included genome-wide genotyping to identify single nucleotide polymorphisms associated with progression in a model incorporating genetic ancestry. One hundred patients self-identified as White (n = 50) or Black (n = 50) were enrolled. Eligibility criteria were modified to facilitate the enrollment of individual Black patients.

RESULTS

The median rPFS for Black and White patients was 16.6 and 16.8 months, respectively; their times to PSA progression (TTP) were 16.6 and 11.5 months, respectively; and their OS was 35.9 and 35.7 months, respectively. Estimated rates of PSA decline by ≥50% in Black and White patients were 74% and 66%, respectively; and PSA declines to <0.2 ng/mL were 26% and 10%, respectively. Rates of grade 3 and 4 hypertension, hypokalemia, and hyperglycemia were higher in Black men.

CONCLUSIONS

Multicenter prospective studies by race are feasible in men with mCRPC but require less restrictive eligibility. Despite higher comorbidity rates, Black patients demonstrated rPFS and OS similar to those of White patients and trended toward greater TTP and PSA declines, consistent with retrospective reports. Importantly, Black men may have higher side-effect rates than White men. This exploratory genome-wide analysis of TTP identified a possible candidate marker of ancestry-dependent treatment outcomes.

Predictors of efficacy of corticosteroid switching from abiraterone plus prednisone to dexamethasone in patients with metastatic castration-resistant prostate cancer

Corticosteroid switching can reverse abiraterone resistance in some patients with metastatic castration-resistant prostate cancer (mCRPC). Here, we investigated the potential biomarkers for predicting the efficacy of corticosteroid switching during treatment with abiraterone acetate (AA). We retrospectively analyzed 101 mCRPC patients receiving corticosteroid switching from West China Hospital and Sun Yat-Sen University Cancer Center between January 2016 and December 2018. All cases received AA plus prednisone as first-line therapy during mCRPC. Primary end points were biochemical progression-free survival (bPFS) and overall survival (OS). The risk groups were defined based on multivariate analysis. A total of 42 (41.6%) and 25 (24.8%) patients achieved 30% and 50% decline in prostate-specific antigen (PSA), respectively, after corticosteroid switching. The median bPFS and median OS on AA plus dexamethasone were 4.9 (95% confidence interval [CI]: 3.7-6.0) months and 18.8 (95% CI: 16.2-30.2) months, respectively. Aldo-keto reductase family 1 member C3 (AKR1C3) expression (hazard ratio [HR]: 2.15, 95% Cl: 1.22-3.80, P = 0.008) and baseline serum alkaline phosphatase (ALP; HR: 4.95, 95% Cl: 2.40-10.19, P < 0.001) were independent predictors of efficacy before corticosteroid switching in the multivariate analysis of bPFS. Only baseline serum ALP >160 IU l^-1 (HR: 3.41, 95% Cl: 1.57-7.38, P = 0.002) together with PSA level at switch ≥50 ng ml^-1 (HR: 2.59, 95% Cl: 1.22-5.47, P = 0.013) independently predicted poorer OS. Based on the predictive factors in multivariate analysis, we developed two risk stratification tools to select candidates for corticosteroid switching. Detection of serum ALP level, PSA level, and tissue AKR1C3 expression in mCRPC patients could help make clinical decisions for corticosteroid switching.

Exosomal TUBB3 mRNA expression of metastatic castration-resistant prostate cancer patients: Association with patient outcome under abiraterone

Background

To use ddPCR to quantify plasma exosomal class III β‐tubulin (βIII‐tubulin, TUBB3, encoded by the TUBB3 gene) mRNA expression in metastatic castration‐resistant prostate cancer (mCRPC) patients, and study the association of this expression with abiraterone efficacy.

Methods

Blood samples were prospectively collected from 52 mCRPC patients using abiraterone as first‐line therapy to measure plasma exosomal TUBB3 mRNA expression value before the initiation of abiraterone. Study endpoints were PSA response rate, PSA‐progression‐free survival (PSA‐PFS), and overall survival (OS, from CRPC to death).

Results

Patients with positive exosomal TUBB3 expression showed shorter PSA‐PFS (negative TUBB3 vs. positive TUBB3: 11.0 vs. 7.9 months; p = 0.014). Further analysis demonstrated that patients with strongly positive exosomal TUBB3 (>20 copies/20 µl) was associated with even shorter PSA‐PFS (negative TUBB3 vs. positive TUBB3 [<20 copies/20 µl] vs. strongly positive TUBB3 [>20 copies/20 µl]: 11.0 vs. 8.3 vs. 3.6 months, p = 0.005). In multivariate analyzes, TUBB3 (+) (HR: 2.114, p = 0.033) and ECOG score >2 (HR: 3.039, p = 0.006) were independent prognosticators of poor PSA‐PFS. PSA response and OS did not present significant differences.

Conclusion

The exosomal TUBB3 mRNA expression level is associated with poor PSA‐PFS of abiraterone in mCRPC patients. The detection of exosomal TUBB3 can be valuable in their management.

Treatment of Metastatic Castration-resistant Prostate Cancer Patients With Abiraterone Acetate and Prednisone and Corresponding Survival Prognostic Factors

BACKGROUND/AIM

The aim of the study was to evaluate the combined treatment with abiraterone acetate and prednisone (AA+P) in patients with castration-resistant prostate cancer (mCPRC), and to identify the survival prognostic factors.

PATIENTS AND METHODS

Patients diagnosed with mCPRC not previously treated with chemotherapy and administered with AA+P were classified into two groups: those with lower and higher survival rates (at 30 months vs. 60 months).

RESULTS

A total of 53 patients were studied at the time of mCRPC diagnosis. Patients with the highest survival rate had suffered prostate cancer for >45 months. At the time of initial prostate cancer diagnosis, they belonged to the risk groups 1-4, had pain intensity measured according to the brief pain inventory (BPI) scale of 0-2, were treated with AA+P>16 months, and had the following tumour marker serum levels: LDH baseline ≤163 U/l, alkaline phosphatase at 6 months ≤56 U/l and PSA at 6 months ≤0.95 ng/ml.

CONCLUSION

Good response to treatment with AA+P for patients with mCRPC was demonstrated. Factors that contributed to the higher prognostic accuracy were time suffering from prostate cancer, the intensity of the pain measured by the BPI scale, the duration of AA+P treatment, and tumour marker levels.

Results of a Randomized Phase II Trial of Intense Androgen Deprivation Therapy prior to Radical Prostatectomy in Men with High-Risk Localized Prostate Cancer

PURPOSE

This multicenter randomized phase 2 trial investigates the impact of intense androgen deprivation on radical prostatectomy pathologic response and radiographic and tissue biomarkers in localized prostate cancer (NCT02903368).

MATERIALS AND METHODS

Eligible patients had a Gleason score ≥4+3=7, prostate specific antigen >20 ng/mL or T3 disease and lymph nodes <20 mm. In Part 1, patients were randomized 1:1 to apalutamide, abiraterone acetate, prednisone and leuprolide (AAPL) or abiraterone, prednisone, leuprolide (APL) for 6 cycles (1 cycle=28 days) followed by radical prostatectomy. Surgical specimens underwent central review. The primary end point was the rate of pathologic complete response or minimum residual disease (minimum residual disease, tumor ≤5 mm). Secondary end points included prostate specific antigen response, positive margin rate and safety. Magnetic resonance imaging and tissue biomarkers of pathologic outcomes were explored.

RESULTS

The study enrolled 118 patients at 4 sites. Median age was 61 years and 94% of patients had high-risk disease. The combined pathologic complete response or minimum residual disease rate was 22% in the AAPL arm and 20% in the APL arm (difference: 1.5%; 1-sided 95% CI -11%, 14%; 1-sided p=0.4). No new safety signals were observed. There was low concordance and correlation between posttherapy magnetic resonance imaging assessed and pathologically assessed tumor volume. PTEN-loss, ERG positivity and presence of intraductal carcinoma were associated with extensive residual tumor.

CONCLUSIONS

Intense neoadjuvant hormone therapy in high-risk prostate cancer resulted in favorable pathologic responses (tumor <5 mm) in 21% of patients. Pathologic responses were similar between treatment arms. Part 2 of this study will investigate the impact of adjuvant hormone therapy on biochemical recurrence.

Safety and efficacy of abiraterone acetate plus prednisolone in patients with castration-resistant prostate cancer: a prospective, observational, post-marketing surveillance study

Background

Abiraterone acetate plus prednisolone is approved to treat patients with castration-resistant prostate cancer. This study evaluated the safety and efficacy of abiraterone acetate plus prednisolone in castration-resistant prostate cancer patients with or without previous chemotherapy in a real-world setting in Japan.

Methods

This study was an observational, prospective, post-marketing surveillance. Castration-resistant prostate cancer patients, who initiated abiraterone acetate after its approval in Japan, were enrolled. Data were collected during an observation period of 12 months and a follow-up period of another 12 months. Adverse events and adverse drug reactions were evaluated for safety. Prostate-specific antigen levels and overall survival were evaluated for efficacy.

Results

From 141 participating institutions, 497 patients were registered: 492 patients including 180 chemotherapy-naïve, 311 chemotherapy-experienced and one off-label-use patient received abiraterone and were evaluated for safety. Adverse events were observed in 225/492 patients (45.7%), adverse drug reactions in 131/492 patients (26.6%) and serious adverse drug reactions in 61/492 patients (12.4%). The most commonly observed adverse drug reaction was abnormal hepatic function (6.5%), followed by hypokalemia (3.0%) and decreased appetite (2.0%). At week 12, 110/432 patients (25.5%) achieved ≥50% decrease from baseline in prostate-specific antigen, and the proportion was higher in chemotherapy-naïve patients (56/161 patients; 34.8%) compared with chemotherapy-experienced patients (54/271 patients; 19.9%, P < 0.001). Survival rates at 24 months were 68.3% (295/432 patients), 73.9% (119/161 chemotherapy-naïve patients) and 64.9% (176/271 chemotherapy-experienced patients).

Conclusions

This large-scale, real-world, post-marketing surveillance study confirmed the safety and efficacy of abiraterone acetate plus prednisolone in Japanese castration-resistant prostate cancer patients with or without previous chemotherapy.

Liquid biopsy reveals KLK3 mRNA as a prognostic marker for progression free survival in patients with metastatic castration-resistant prostate cancer undergoing first-line abiraterone acetate and prednisone treatment

Circulating RNAs extracted from liquid biopsies represent a promising source of cancer‐ and therapy‐related biomarkers. We screened whole blood from patients with metastatic castration‐resistant prostate cancer (mCRPC) following their first‐line treatment with abiraterone acetate and prednisone (AA‐P) to identify circulating RNAs that may correlate with progression‐free survival (PFS). In a prospective multicenter observational study, 53 patients with mCRPC were included after they started first‐line AA‐P treatment. Blood was drawn at baseline, 1, 3, and 6 months after treatment initiation. The levels of predefined circulating RNAs earlier identified as being upregulated in patients with mCRPC (e.g., microRNAs, long noncoding RNAs, and mRNAs), were analyzed. Uni‐ and multivariable Cox regression and Kaplan–Meier analyses were used to analyze the prognostic value of the various circulating RNAs for PFS along treatment. Detectable levels of kallikrein‐related peptidase 3 (KLK3) mRNA at baseline were demonstrated to be an independent prognostic marker for PFS (201 vs 501 days, P = 0.00054). Three months after AA‐P treatment initiation, KLK3 could not be detected in the blood of responding patients, but was still detectable in 56% of the patients with early progression. Our study confirmed that KLK3 mRNA detection in whole blood is an independent prognostic marker in mCRPC patients receiving AA‐P treatment. Furthermore, the levels of circulating KLK3 mRNA in patients receiving AA‐P treatment might reflect treatment response or early signs of progression.

Cost-effectiveness analysis of enzalutamide for patients with chemotherapy-naïve metastatic castration-resistant prostate cancer in Japan

Background

We aimed to evaluate cost-effectiveness of enzalutamide in chemotherapy-naïve metastatic castration-resistant prostate cancer patients in Japan.

Methods

A Markov model was developed to capture time spent by patients in various health states: stable, progression and death. Abiraterone acetate and docetaxel were set as active comparators. Clinical outcomes were obtained from the PREVAIL, COU-AA-302 and TAX327 trials. Treatment sequence, concomitant drugs and therapies for adverse events were estimated from responses to a survey by 14 Japanese prostate cancer experts. The analytic perspective was public healthcare payer, with a 10-year time horizon. The incremental cost-effectiveness ratio was estimated from quality-adjusted life-years and Japanese public healthcare costs. Probabilistic sensitivity analysis was performed to assess the robustness of the findings.

Results

According to the survey, the most common treatment sequences were (i) enzalutamide → docetaxel → cabazitaxel (enzalutamide-first sequencing), (ii) abiraterone → enzalutamide → docetaxel (abiraterone-first sequencing) and (iii) docetaxel→ enzalutamide → cabazitaxel (docetaxel-first sequencing). In the base-case analysis, enzalutamide-first sequencing saved 1.74 million Japanese Yen versus abiraterone-first sequencing, with a 0.129 quality-adjusted life-year gain (dominant). Enzalutamide-first sequencing had a cost increase of 4.44 million Japanese Yen over docetaxel-first sequencing, with a 0.371 quality-adjusted life-years gain. The incremental cost-effectiveness ratio of enzalutamide-first sequencing versus docetaxel-first sequencing was estimated as 11.94 million Japanese Yen/quality-adjusted life-years. Probabilistic sensitivity analyses demonstrated that, compared with abiraterone-first sequencing, enzalutamide-first sequencing had an 87.4% probability of being dominant.

Conclusions

Results modeled herein suggest that the enzalutamide-first sequencing is more cost-effective than the abiraterone-first sequencing, but less cost-effective than docetaxel-first sequencing for chemotherapy-naïve patients with metastatic castration-resistant prostate cancer.

Synergistic Effect of Statins and Abiraterone Acetate on the Growth Inhibition of Neuroblastoma via Targeting Androgen Receptor

Neuroblastoma is the most common extracranial neuroendocrine tumor in childhood. Although many studies have tried to find effective treatments, there are still numerous limitations in current clinical targeted therapy. So, it is important to find new therapeutic targets and strategies from a new perspective. Our previous study reported that the androgen receptor (AR) promotes the growth of neuroblastoma in vitro and in vivo. Based on documentary investigation, we postulated that the AR–SCAP–SREBPs-CYP17/HMGCR axis may regulate cholesterol and androgens synthesis and form a positive enhancement loop promoting NB progression. Clinical samples and Oncomine database analysis proved the activation of AR–SCAP–SREBPs-CYP17/HMGCR axis in neuroblastoma. The combination of inhibitors of HMGCR (statins) and CYP17A1 (abiraterone acetate) showed synergistic effect that significantly inhibited the proliferation and migration with decreased expression of related genes detected in vitro and in vivo suggesting the dual-targeted therapy had the potential to inhibit the progression of neuroblastoma in spite of its MYCN status. This study provides new ideas for clinical treatment of neuroblastoma with efficacy and reduced toxicity.

Recent trend of androgen deprivation therapy in newly diagnosed prostate cancer patients: Comparing between high- and middle-income Asian countries

The number of newly diagnosed prostate cancer cases varies across Asia, with higher mortality‐to‐incidence ratio reported in developing nations. Androgen deprivation therapy (ADT), alone or in combination, remains the mainstay of first‐line treatment for advanced prostate cancer. Key findings of extensive research and randomized controlled trials have shaped current clinical practice and influenced clinical guideline recommendations. We describe here the recent trend of ADT in newly diagnosed prostate cancer for Asia focusing on Japan (high‐income country) and Malaysia (middle‐income country) based on the Asian Prostate Cancer (A‐CaP) Study. The combination of radiotherapy and ADT or ADT alone was common in patients with intermediate‐to‐high risk localized and locally advanced disease. For metastatic prostate cancer, maximum androgen blockade (gonadotrophin‐releasing hormone [GnRH] agonist/antagonist plus antiandrogen) was prevalent among the Japanese patients while primary ADT alone with GnRH agonist/antagonist was widely practiced in the Malaysian cohort. Upfront combined therapy (ADT plus docetaxel or androgen receptor pathway inhibitor) has significantly improved the outcomes of patients with metastatic castration‐naïve prostate cancer. Its application, however, remains low in our cohorts due to patients’ financial capacity and national health insurance coverage. Early detection remains the cornerstone in prostate cancer control to improve treatment outcome and patient survival.

Targeting backdoor androgen synthesis through AKR1C3 inhibition: A presurgical hormonal ablative neoadjuvant trial in high-risk localized prostate cancer

BACKGROUND

Localized prostate cancers (PCs) may resist neoadjuvant androgen receptor (AR)-targeted therapies as a result of persistent intraprostatic androgens arising through upregulation of steroidogenic enzymes. Therefore, we sought to evaluate clinical effects of neoadjuvant indomethacin (Indo), which inhibits the steroidogenic enzyme AKR1C3, in addition to combinatorial anti-androgen blockade, in men with high-risk PC undergoing radical prostatectomy (RP).

METHODS

This was an open label, single-site, Phase II neoadjuvant trial in men with high to very-high-risk PC, as defined by NCCN criteria. Patients received 12 weeks of apalutamide (Apa), abiraterone acetate plus prednisone (AAP), degarelix, and Indo followed by RP. Primary objective was to determine the pathologic complete response (pCR) rate. Secondary objectives included minimal residual disease (MRD) rate, defined as residual cancer burden (RCB) ≤ 0.25cm³ (tumor volume multiplied by tumor cellularity) and elucidation of molecular features of resistance.

RESULTS

Twenty patients were evaluable for the primary endpoint. Baseline median prostate-specific antigen (PSA) was 10.1 ng/ml, 4 (20%) patients had Gleason grade group (GG) 4 disease and 16 had GG 5 disease. At RP, 1 (5%) patient had pCR and 6 (30%) had MRD. Therapy was well tolerated. Over a median follow-up of 23.8 months, 1 of 7 (14%) men with pathologic response and 6 of 13 (46%) men without pathologic response had a PSA relapse. There was no association between prostate hormone levels or HSD3B1 genotype with pathologic response.

CONCLUSIONS

In men with high-risk PC, pCR rates remained low even with combinatorial AR-directed therapy, although rates of MRD were higher. Ongoing follow-up is needed to validate clinical outcomes of men who achieve MRD.