Adding abiraterone or docetaxel to long-term hormone therapy for prostate cancer: directly randomised data from the STAMPEDE multi-arm, multi-stage platform protocol

Androgen Receptor Splice Variant 7 Predicts Shorter Response in Patients with Metastatic Hormone-sensitive Prostate Cancer Receiving Androgen Deprivation Therapy

BACKGROUND

Whether AR-V7 expression can predict the response in patients with metastatic hormone-sensitive prostate cancer (mHSPC) who receive androgen deprivation therapy (ADT) remains to be explored.

OBJECTIVE

To evaluate the predictive value of AR-V7 expression in the prognosis of mHSPC patients receiving ADT.

DESIGN, SETTING, AND PARTICIPANTS

In this multicenter prospective cohort study, 310 mHSPC patients commencing ADT were enrolled. Standard immunohistochemical staining was used to assess AR-V7 protein expression in biopsy tissues collected before initiation of ADT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Kaplan-Meier survival estimates and Cox regression analyses were used to evaluate associations of AR-V7 status (positive vs negative) with progression-free survival (PFS) and overall survival (OS).

RESULTS AND LIMITATIONS

Sixty-four (21%) patients were AR-V7-positive and 246 (79%) patients were AR-V7-negative. The median follow-up for patients not confirmed dead was 25 mo (interquartile range 10-30). Compared to AR-V7-negative patients, AR-V7-positive patients had significantly shorter PFS (hazard ratio [HR] 47.39, 95% confidence interval [CI] 25.83-86.94) and OS (HR 3.57, 95% CI 1.46-8.72). In multivariable analysis, AR-V7 was an independent predictive factor (HR 7.61, 95% CI 5.24-11.06) for shorter PFS. Limitations include the sample size and follow-up period.

CONCLUSIONS

AR-V7 expression in primary cancer tissue is correlated with poor prognosis for mHSPC patients receiving ADT.

PATIENT SUMMARY

In this study of men with metastatic hormone-sensitive prostate cancer, AR-V7 protein expression in primary cancer tissue was associated with poor outcomes on androgen deprivation therapy.

Prostate cancer

Prostate cancer is a complex disease that affects millions of men globally, predominantly in high human development index regions. Patients with localized disease at a low to intermediate risk of recurrence generally have a favourable outcome of 99% overall survival for 10 years if the disease is detected and treated at an early stage. Key genetic alterations include fusions of TMPRSS2 with ETS family genes, amplification of the MYC oncogene, deletion and/or mutation of PTEN and TP53 and, in advanced disease, amplification and/or mutation of the androgen receptor (AR). Prostate cancer is usually diagnosed by prostate biopsy prompted by a blood test to measure prostate-specific antigen levels and/or digital rectal examination. Treatment for localized disease includes active surveillance, radical prostatectomy or ablative radiotherapy as curative approaches. Men whose disease relapses after prostatectomy are treated with salvage radiotherapy and/or androgen deprivation therapy (ADT) for local relapse, or with ADT combined with chemotherapy or novel androgen signalling-targeted agents for systemic relapse. Advanced prostate cancer often progresses despite androgen ablation and is then considered castration-resistant and incurable. Current treatment options include AR-targeted agents, chemotherapy, radionuclides and the poly(ADP-ribose) inhibitor olaparib. Current research aims to improve prostate cancer detection, management and outcomes, including understanding the fundamental biology at all stages of the disease.

Prostate cancer

Prostate cancer is a complex disease that affects millions of men globally, predominantly in high human development index regions. Patients with localized disease at a low to intermediate risk of recurrence generally have a favourable outcome of 99% overall survival for 10 years if the disease is detected and treated at an early stage. Key genetic alterations include fusions of TMPRSS2 with ETS family genes, amplification of the MYC oncogene, deletion and/or mutation of PTEN and TP53 and, in advanced disease, amplification and/or mutation of the androgen receptor (AR). Prostate cancer is usually diagnosed by prostate biopsy prompted by a blood test to measure prostate-specific antigen levels and/or digital rectal examination. Treatment for localized disease includes active surveillance, radical prostatectomy or ablative radiotherapy as curative approaches. Men whose disease relapses after prostatectomy are treated with salvage radiotherapy and/or androgen deprivation therapy (ADT) for local relapse, or with ADT combined with chemotherapy or novel androgen signalling-targeted agents for systemic relapse. Advanced prostate cancer often progresses despite androgen ablation and is then considered castration-resistant and incurable. Current treatment options include AR-targeted agents, chemotherapy, radionuclides and the poly(ADP-ribose) inhibitor olaparib. Current research aims to improve prostate cancer detection, management and outcomes, including understanding the fundamental biology at all stages of the disease.

Treating Prostate Cancer by Antibody-Drug Conjugates

Prostate cancer is the most frequent malignancy in the worldwide male population; it is also one of the most common among all the leading cancer-related death causes. In the last two decades, the therapeutic scenario of metastatic castration-resistant prostate cancer has been enriched by the use of chemotherapy and androgen receptor signaling inhibitors (ARSI) and, more recently, by immunotherapy and poly(ADP–ribose) polymerase (PARP) inhibitors. At the same time, several trials have shown the survival benefits related to the administration of novel ARSIs among patients with non-castration-resistant metastatic disease along with nonmetastatic castration-resistant cancer too. Consequently, the therapeutic course of this malignancy has been radically expanded, ensuring survival benefits never seen before. Among the more recently emerging agents, the so-called “antibody–drug conjugates” (ADCs) are noteworthy because of their clinical practice changing outcomes obtained in the management of other malignancies (including breast cancer). The ADCs are novel compounds consisting of cytotoxic agents (also known as the payload) linked to specific antibodies able to recognize antigens expressed over cancer cells’ surfaces. As for prostate cancer, researchers are focusing on STEAP1, TROP2, PSMA, CD46 and B7-H3 as optimal antigens which may be targeted by ADCs. In this paper, we review the pivotal trials that have currently changed the therapeutic approach to prostate cancer, both in the nonmetastatic castration-resistant and metastatic settings. Therefore, we focus on recently published and ongoing trials designed to investigate the clinical activity of ADCs against prostate malignancy, characterizing these agents. Lastly, we briefly discuss some ADCs-related issues with corresponding strategies to overwhelm them, along with future perspectives for these promising novel compounds.

99mTc-PSMA SPECT/CT Versus 68Ga-PSMA PET/CT in the Evaluation of Metastatic Prostate Cancer

BACKGROUND

99mTc-prostate-specific membrane antigen (PSMA) SPECT/CT is less expensive and readily available modality compared with 68Ga-PSMA PET/CT for imaging prostate cancer (PC). The aim of this study is to compare the value of these 2 modalities in patients confirmed or suspicious to have metastatic prostate cancer.

PATIENTS AND METHODS

Twenty-two patients with the mean age of 66.6 ± 10.1 years were studied using 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT, with less than 7 days interval between the 2 imaging procedures. Whole-body PET/CT was done 60 minutes after IV injection of 185 MBq (5 mCi) of 68Ga-PSMA. 99mTc-PSMA SPECT/CT was performed 3 hours after IV injection of 555 to 740 MBq (15-20 mCi) of 99mTc-PSMA. The images of each modality were interpreted independently, and the results were compared according to patient-based as well as region-based analyses.

RESULTS

In patient-based evaluation, both 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT scans were positive in 95.45% (21/22). In region-based evaluation, 68Ga-PSMA PET/CT detected 53 regions (median of 2 regions per patient; range, 0-5), whereas 43 (median of 2 regions per patient; range, 0-5) were detected by 99mTc-PSMA SPECT/CT. Most of these differences could be explained by lower detection rate of 99mTc-PSMA SPECT/CT in prostate bed (n = 6). PET/CT detected more involved regions than SPECT/CT (P = 0.007), whereas similar frequency of extraprostatic lesions were diagnosed in both modalities (P = 0.102). Significant correlation was also demonstrated between serum prostate-specific antigen level and imaging parameters of disease extension detected by 2 modalities.

CONCLUSIONS

99mTc-PSMA SPECT/CT could be a potential substitute for 68Ga-PSMA PET/CT in high-risk patients, except when evaluation of prostate bed is of major concern.

Implementation and Impact of a Risk-Stratified Prostate Cancer Screening Algorithm as a Clinical Decision Support Tool in a Primary Care Network

BACKGROUND

Implementation methods of risk-stratified cancer screening guidance throughout a health care system remains understudied.

OBJECTIVE

Conduct a preliminary analysis of the implementation of a risk-stratified prostate cancer screening algorithm in a single health care system.

DESIGN

Comparison of men seen pre-implementation (2/1/2016-2/1/2017) vs. post-implementation (2/2/2017-2/21/2018).

PARTICIPANTS

Men, aged 40-75 years, without a history of prostate cancer, who were seen by a primary care provider.

INTERVENTIONS

The algorithm was integrated into two components in the electronic health record (EHR): in Health Maintenance as a personalized screening reminder and in tailored messages to providers that accompanied prostate-specific antigen (PSA) results.

MAIN MEASURES

Primary outcomes: percent of men who met screening algorithm criteria; percent of men with a PSA result. Logistic repeated measures mixed models were used to test for differences in the proportion of individuals that met screening criteria in the pre- and post-implementation periods with age, race, family history, and PSA level included as covariates.

KEY RESULTS

During the pre- and post-implementation periods, 49,053 and 49,980 men, respectively, were seen across 26 clinics (20.6% African American). The proportion of men who met screening algorithm criteria increased from 49.3% (pre-implementation) to 68.0% (post-implementation) (p < 0.001); this increase was observed across all races, age groups, and primary care clinics. Importantly, the percent of men who had a PSA did not change: 55.3% pre-implementation, 55.0% post-implementation. The adjusted odds of meeting algorithm-based screening was 6.5-times higher in the post-implementation period than in the pre-implementation period (95% confidence interval, 5.97 to 7.05).

CONCLUSIONS

In this preliminary analysis, following implementation of an EHR-based algorithm, we observed a rapid change in practice with an increase in screening in higher-risk groups balanced with a decrease in screening in low-risk groups. Future efforts will evaluate costs and downstream outcomes of this strategy.

Prostate cryoablation combined with androgen deprivation therapy for newly diagnosed metastatic prostate cancer: a propensity score-based study

BACKGROUND

Several studies showed that androgen deprivation therapy (ADT) plus local treatment of prostate could improve metastatic prostate cancer (mPCa) patients' survival. To date there are few studies analyzed the value of prostate cryoablation in mPCa. The objective of our analysis is to evaluate the oncological results and clinical value of prostate cryoablation combined with ADT compared with ADT alone in newly diagnosed mPCa patients.

METHODS

Newly diagnosed mPCa patients undergoing cryoablation plus ADT (group A) between January 2011 and November 2018 were identified. Patients receiving ADT alone (group B) were selected from the same institutional prostate cancer database by propensity score matching based on clinical characteristics. Oncological results and clinical value in symptom control and primary lesion treatment were compared.

RESULTS

Fifty-four patients were included in each group. Prostate cryoablation was well tolerated. The median follow-up time was 40 (27-53) and 39 (31-54) months in group A and group B, respectively. Patients in group A had a lower median prostate-specific antigen (PSA) nadir (0.025 ng/mL vs. 0.230 ng/mL, p = 0.001), longer median failure-free survival (FFS) (39 months vs. 21 months, p = 0.005), and median metastatic castration-resistant prostate cancer (mCRPC)-free survival (39 months vs. 21 months, p = 0.007). No difference in cancer-specific survival and overall survival was found between the two groups. Multivariate Cox analysis showed combination therapy reduced the risk of FFS by 45.8% (HR = 0.542 [95% CI 0.329-0.893]; p = 0.016). Patients in group A had better clinical relief of urinary symptoms (79.1 vs. 59.1%, p = 0.044) and required less treatment of primary lesions for symptomatic relief (13.0 vs. 31.5%, p = 0.021).

CONCLUSIONS

Prostate cryoablation plus ADT decreases PSA nadir, prolongs FFS and mCRPC-free survival, relieves urinary symptoms and reduces the need for treating primary lesions in newly diagnosed mPCa patients compared to ADT alone.

Systemic treatment options for metastatic hormone-sensitive prostate cancer: making sense of the data

PURPOSE OF REVIEW

Systemic treatment options for metastatic hormone-sensitive prostate cancer (mHSPC) have recently shifted from the traditional androgen deprivation therapy (ADT) monotherapy to multidrug approaches incorporating drugs initially approved for castration-resistant state and ADT. However, clinicians have difficulties in choosing the adequate combination therapy for individualized patient care, because of the lack of consensus regarding disease risk factors, differences in study design of the major clinical trials and lack of direct comparisons between drugs. The aim of this review is to provide an update of the current treatment options for this heterogenous group of patients.

RECENT FINDINGS

Current oncological guidelines strongly recommend that patients with newly diagnosed mHSPC and high-volume disease (CHAARTED criteria) should receive docetaxel and ADT, whereas those with high-risk disease (LATITUDE criteria) abiraterone and ADT. Recently, the Food and Drug Administration approved apalutamide and enzalutamide for mHSPC. Moreover, new data support the efficacy of docetaxel and abiraterone in patients with mHSPC, regardless of metastatic burden.

SUMMARY

Today, the combination approach should be recommended for newly diagnosed mHSPC over ADT monotherapy, but treatment initiation must be personalized based on disease, drug and patient characteristics. Thanks to continuous efforts and progress in patient and disease-related outcomes, mHSPC could become a chronic disease.

To treat or not to treat: is it acceptable to avoid active therapies in advanced prostate cancer today?

Introduction: Recently, there has been a paradigm shift in the treatment of advanced prostate cancer (PCa) because the approval of a number of new agents has significantly improved overall survival. However, as PCa is a heterogeneous disease that may be more or less aggressive and patients may be more or less responsive to treatment, it is often debated whether or not it is acceptable to avoid active therapies.Areas covered: This review discusses different settings of advanced PCa.Expert opinion: In metastatic castration-resistant PCa, it is unethical not to use active treatments but the use of both androgen receptor targeting agents (ARTA) in sequence should be avoided in most patients and the use of the available agents for fourth-line treatment or beyond should only be considered for highly selected patients. In metastatic hormone-sensitive PCa, patients with de novo disease should receive one additional agent in combination with androgen deprivation therapy (ADT), whereas patients in relapse should be managed with ADT alone. In non-metastatic castration-resistant prostate cancer (PCa), all patients with a PSA doubling time of ≤6 months should receive one ARTA, whereas the others might wait until there is an acceleration in the kinetics of their PSA levels.

First-line systemic therapy for metastatic castration-sensitive prostate cancer: An updated systematic review with novel findings

Although both docetaxel and androgen-receptor-axis-targeted (ARAT) agents have yielded survival improvements in combination with androgen deprivation therapy (ADT) compared to ADT alone in metastatic castration-sensitive prostate cancer (mCSPC) patients, the optimal therapeutic choice remains to be established. We analyzed estimates of the hazard ratios for death (OS-HRs) in patients treated in the first-line setting enrolled in the GETUG-AFU15, CHAARTED, STAMPEDE, LATITUDE, ENZAMET, and TITAN trials. Overall, men with mCSPC receiving ADT with vs. without either an ARAT agent or docetaxel as first-line systemic therapy showed a pooled OS-HR of 0.69 (95 % CI: 0.61-0.78), with significant heterogeneity (p = 0.045, I² = 52.5 %). Network meta-analysis showed an OS-HR in patients receiving an ARAT agent vs. docetaxel of 0.78 (95 %CI: 0.67-0.91). In conclusion, the evidence analysed indicates that an ARAT agent may provide improved OS outcomes compared to docetaxel. Prospective randomized trials are warranted.

Abiraterone acetate in combination with androgen deprivation therapy compared to androgen deprivation therapy only for metastatic hormone-sensitive prostate cancer

BACKGROUND

Systemic androgen deprivation therapy (ADT), also referred to as hormone therapy,àhas long been the primary treatment for metastatic prostate cancer. Additional agents have been reserved for the castrate-resistant disease stage when ADT start becoming less effective. Abiraterone is an agent with an established role in that disease stage, which has only recently been evaluated in the hormone-sensitive setting.

OBJECTIVES

To assess the effects of early abiraterone acetate, in combination with systemic ADT, for newly diagnosed metastatic hormone-sensitive prostate cancer.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, six other databases, two trials registries, grey literature, and conference proceedings, up to 15 May 2020. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized trials, in which men diagnosed with hormone-sensitive prostate cancer were administered abiraterone acetate and prednisolone with ADT or ADTàalone.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data from the included studies. We performed statistical analyses using a random-effects model. We rated the quality of evidence according to the GRADE approach.

MAIN RESULTS

The search identified two randomized controlled trials (RCT), with 2201 men, who were assigned to receive either abiraterone acetate 1000 mg once daily and low dose prednisone (5mg) in addition to ADT, or ADT alone. In the LATITUDE trial, the median age and range of men in the intervention group was 68 (38 to 89) years, and 67 (33 to 92) years in the control group. Nearly all of the men in thisàstudy (97.6%) had prostate cancer with a Gleason score of at least 8 (ISUP grade group 4). Primary outcomes The addition of abiraterone acetate to ADT reduces the probability of death from any cause compared to ADT alone (hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.56 to 0.73; 2 RCTs, 2201 men; high certainty of evidence); this corresponds to 163 fewer deaths per 1000 men with hormone-sensitive metastaticàprostate cancerà(210 fewer to 115 fewer) at five years. Abiraterone acetate in addition to ADT probably results in little to no differenceàin quality of life compared to ADT alone, measured with the Functional Assessment of Cancer Therapy-prostate total score (FACT-P; range 0 to 156; higher values indicates better quality of life),àat 12 months (mean difference [MD] 2.90 points, 95% CI 0.11 to 5.60; 1 RCT, 838 men; moderate certainty of evidence). Secondary outcomes Abiraterone plus ADT increases the risk of grades III to V adverse events compared to ADT alone (risk ratio [RR] 1.34, 95% CI 1.22 to 1.47; 1 RCT, 1199 men; high certainty of evidence); this corresponds to 162 more grade III to Vàevents per 1000 men with hormone-sensitive metastaticàprostate cancerà(105 more to 224 more) at a median follow-up of 30àmonths. Abiraterone acetate in addition to ADT probably reduces the probability of death due to prostate cancer compared to ADT alone (HR 0.58, 95% CI 0.50 to 0.68; 2 RCTs, 2201 men; moderate certainty of evidence). This corresponds to 120 fewer death from prostate cancer per 1000 men with hormone-sensitive metastaticàprostate cancerà(95% CI 145 fewer to 90 fewer) afteràa median follow-up of 30 months. The addition of abiraterone acetate to ADT probably decreases the probability of disease progression compared to ADT alone (HR 0.35, 95%CI 0.26 to 0.49; 2 RCTs, 2097 men; moderate certainty of evidence). This corresponds to 369 fewer incidences of disease progression per 1000 men with hormone-sensitive metastaticàprostate cancerà(456 fewer to 256 fewer)àafter a median follow-up of 30 months. The addition of abiraterone acetate to ADT probably increases the risk of discontinuing treatment due to adverse events compared to ADT alone (RR 1.50, 95% CI 1.17 to 1.92; 1 RCT, 1199 men; moderate certainty of evidence). This corresponds to 51 more men (95% CI 17 more to 93 more) discontinuing treatment because of adverse events per 1000 men treated with abiraterone acetate and ADT compared to ADT alone afteràa median follow-up of 30 months.

AUTHORS' CONCLUSIONS

The addition of abiraterone acetate to androgen deprivation therapy improves overall survival but probably not quality of life. Itàprobably also extends disease-specific survival, and delays disease progression compared to androgen deprivation therapy alone. However, the risk of grades III to V adverse events is increased, and probably, so is the risk of discontinuing treatment due to adverse events.

Management of Advanced Prostate Cancer in Clinical Practice: Real-World Answers to Challenging Dilemmas

Advanced prostate cancer is a continuum of states distinguished by the presence or absence of metastasis and sensitivity or resistance to androgen deprivation therapy (ADT). Therapeutic options for this disease continue to rapidly evolve, making it a challenge to apply results of clinical trial data to daily patient management. One question relevant to providers is whether molecular biomarkers predictive of response or resistance to therapies are available to guide clinical treatment decisions. Other salient topics include the timing of therapy initiation in patients with biochemical recurrence, treatment approach in low-volume versus high-volume metastatic castrate-sensitive prostate cancer, types of agents available beyond ADT, and timing of their use in men with nonmetastatic castrate-resistant prostate cancer as well as whether sequencing of therapies in metastatic castrate-resistant prostate cancer matters. Additionally, familiarity with emerging treatment strategies is important. This review addresses the gray areas and challenging questions in advanced prostate cancer management that frequently arise in clinical practice.

Does the Addition of Abiraterone to Castration Affect the Reduction in Bone Mineral Density?

BACKGROUND/AIM

The in vivo effect of abiraterone on bone mineral density (BMD) in addition to androgen deprivation therapy was examined using a murine model.

MATERIALS AND METHODS

The mice were separated into the following groups: control, abiraterone, castration, and castration+abiraterone. The percentage change in the ratio of bone to tissue volume (BV/TV), number of osteoblasts and osteoclasts, and the serum level of bone markers were compared on day 21.

RESULTS

The BV/TV ratio of the abiraterone, castration, and castration+abiraterone groups was lower than that of the control group. However, the change in the BV/TV ratio in the castration+abiraterone group was not significantly different from that in the castration group. There was no significant difference in the serum TRAP5b level and the number of osteoclasts and osteoblasts between the castration+abiraterone and the castration groups.

CONCLUSION

The addition of abiraterone to castration did not affect BMD in the murine model.

EAU-EANM-ESTRO-ESUR-SIOG Guidelines on Prostate Cancer. Part II-2020 Update: Treatment of Relapsing and Metastatic Prostate Cancer

OBJECTIVE

To present a summary of the 2020 version of the European Association of Urology (EAU)-European Association of Nuclear Medicine (EANM)-European Society for Radiotherapy & Oncology (ESTRO)-European Society of Urogenital Radiology (ESUR)-International Society of Geriatric Oncology (SIOG) guidelines on the treatment of relapsing, metastatic, and castration-resistant prostate cancer (CRPC).

EVIDENCE ACQUISITION

The working panel performed a literature review of the new data (2016-2019). The guidelines were updated, and the levels of evidence and/or grades of recommendation were added based on a systematic review of the literature.

EVIDENCE SYNTHESIS

Prostate-specific membrane antigen positron emission tomography computed tomography scanning has developed an increasingly important role in men with biochemical recurrence after local therapy. Early salvage radiotherapy after radical prostatectomy appears as effective as adjuvant radiotherapy and, in a subset of patients, should be combined with androgen deprivation. New treatments have become available for men with metastatic hormone-sensitive prostate cancer (PCa), nonmetastatic CRPC, and metastatic CRPC, along with a role for local radiotherapy in men with low-volume metastatic hormone-sensitive PCa. Also included is information on quality of life outcomes in men with PCa.

CONCLUSIONS

The knowledge in the field of advanced and metastatic PCa and CRPC is changing rapidly. The 2020 EAU-EANM-ESTRO-ESUR-SIOG guidelines on PCa summarise the most recent findings and advice for use in clinical practice. These PCa guidelines are first endorsed by the EANM and reflect the multidisciplinary nature of PCa management. A full version is available from the EAU office or online (http://uroweb.org/guideline/prostate-cancer/).

PATIENT SUMMARY

This article summarises the guidelines for the treatment of relapsing, metastatic, and castration-resistant prostate cancer. These guidelines are evidence based and guide the clinician in the discussion with the patient on the treatment decisions to be taken. These guidelines are updated every year; this summary spans the 2017-2020 period of new evidence.

Predicting new drug indications for prostate cancer: The integration of an in silico proteochemometric network pharmacology platform with patient-derived primary prostate cells

BACKGROUND

Drug repurposing enables the discovery of potential cancer treatments using publically available data from over 4000 published Food and Drug Administration approved and experimental drugs. However, the ability to effectively evaluate the drug's efficacy remains a challenge. Impediments to broad applicability include inaccuracies in many of the computational drug-target algorithms and a lack of clinically relevant biologic modeling systems to validate the computational data for subsequent translation.

METHODS

We have integrated our computational proteochemometric systems network pharmacology platform, DrugGenEx-Net, with primary, continuous cultures of conditionally reprogrammed (CR) normal and prostate cancer (PCa) cells derived from treatment-naive patients with primary PCa.

RESULTS

Using the transcriptomic data from two matched pairs of benign and tumor-derived CR cells, we constructed drug networks to describe the biological perturbation associated with each prostate cell subtype at multiple levels of biological action. We prioritized the drugs by analyzing these networks for statistical coincidence with the drug action networks originating from known and predicted drug-protein targets. Prioritized drugs shared between the two patients' PCa cells included carfilzomib (CFZ), bortezomib (BTZ), sulforaphane, and phenethyl isothiocyanate. The effects of these compounds were then tested in the CR cells, in vitro. We observed that the IC50 values of the normal PCa CR cells for CFZ and BTZ were higher than their matched tumor CR cells. Transcriptomic analysis of CFZ-treated CR cells revealed that genes involved in cell proliferation, proteases, and downstream targets of serine proteases were inhibited while KLK7 and KLK8 were induced in the tumor-derived CR cells.

CONCLUSIONS

Given that the drugs in the database are extremely well-characterized and that the patient-derived cells are easily scalable for high throughput drug screening, this combined in vitro and in silico approach may significantly advance personalized PCa treatment and for other cancer applications.

Comparison of Current Systemic Combination Therapies for Metastatic Hormone-Sensitive Prostate Cancer and Selection of Candidates for Optimal Treatment: A Systematic Review and Bayesian Network Meta-Analysis

Objective: To compare the efficacy and safety of current systemic combination therapies for patients with mHSPC and help select candidates for optimal treatment.

Methods: Databases of MEDLINE and EMBASE, Cochrane Central Register of Controlled Trials, and Clinical Trial.gov were searched for eligible studies. Direct and network meta-analysis were conducted to compare various systemic combination therapies and the surface under the cumulative ranking curve (SUCRA) was generated for treatment ranking. Subgroup analyses were performed according to the extent of metastasis. Adverse events (AEs) were compared among the effective treatments.

Results: Ten trials with 16 publications were included in this network meta-analysis. Direct and network meta-analysis consistently suggested that androgen-deprivation therapy (ADT) combined with docetaxel, abiraterone, enzalutamide, or apalutamide could significantly improve overall survival (OS) and failure-free survival (FFS) compared to ADT alone in men with mHSPC. SUCRA analysis demonstrated the superiority of ADT plus abiraterone or enzalutamide over other therapies. Subgroup analyses indicated that additional abiraterone to ADT had the highest ranking in patients with high-volume diseases or visceral metastases and enzalutamide plus ADT outperformed other treatments in patients with low-volume diseases or without visceral metastases. Different combination therapies had variable AE profiles and ADT in addition with docetaxel or abiraterone had the highest risk of AEs.

Conclusion: ADT plus docetaxel, abiraterone, enzalutamide, or apalutamide were associated with significantly improved survival in patients with mHSPC. ADT plus abiraterone or enzalutamide appeared to be the most effective treatments. Clinicians should balance the efficacy, potential AEs, and disease status to select the optimal treatment.

An overview of platform trials with a checklist for clinical readers

OBJECTIVES

The objective of the study was to outline key considerations for general clinical readers when critically evaluating publications on platform trials and for researchers when designing these types of clinical trials.

STUDY DESIGN AND SETTING

In this review, we describe key concepts of platform trials with case study discussion of two hallmark platform trials in STAMPEDE and I-SPY2. We provide reader's guide to platform trials with a critical appraisal checklist.

RESULTS

Platform trials offer flexibilities of dropping ineffective arms early based on interim data and introducing new arms into the trial. For platform trials, it is important to consider how interventions are compared and evaluated throughout and how new interventions are introduced. For intervention comparisons, it is important to consider what the primary analysis is, what and how many interventions are active simultaneously, and allocation between different arms. Interim evaluation considerations should include the number and timing of interim evaluations and outcomes and statistical rules used to drop interventions. New interventions are usually introduced based on scientific merits, so consideration of these merits is important, together with the timing and mechanisms in which new interventions are added.

CONCLUSION

More efforts are needed to improve the scientific literacy of platform trials. Our review provides an overview of the important concepts of platform trials.

Repurposing old drugs to fight multidrug resistant cancers

Overcoming multidrug resistance represents a major challenge for cancer treatment. In the search for new chemotherapeutics to treat malignant diseases, drug repurposing gained a tremendous interest during the past years. Repositioning candidates have often emerged through several stages of clinical drug development, and may even be marketed, thus attracting the attention and interest of pharmaceutical companies as well as regulatory agencies. Typically, drug repositioning has been serendipitous, using undesired side effects of small molecule drugs to exploit new disease indications. As bioinformatics gain increasing popularity as an integral component of drug discovery, more rational approaches are needed. Herein, we show some practical examples of in silico approaches such as pharmacophore modelling, as well as pharmacophore- and docking-based virtual screening for a fast and cost-effective repurposing of small molecule drugs against multidrug resistant cancers. We provide a timely and comprehensive overview of compounds with considerable potential to be repositioned for cancer therapeutics. These drugs are from diverse chemotherapeutic classes. We emphasize the scope and limitations of anthelmintics, antibiotics, antifungals, antivirals, antimalarials, antihypertensives, psychopharmaceuticals and antidiabetics that have shown extensive immunomodulatory, antiproliferative, pro-apoptotic, and antimetastatic potential. These drugs, either used alone or in combination with existing anticancer chemotherapeutics, represent strong candidates to prevent or overcome drug resistance. We particularly focus on outcomes and future perspectives of drug repositioning for the treatment of multidrug resistant tumors and discuss current possibilities and limitations of preclinical and clinical investigations.

Efficacy and Safety of Androgen-Deprivation Therapy Combined with Docetaxel Plus Prednisone in High-Burden Metastatic Hormone-Sensitive Prostate Cancer

Purpose

The aim of this study was to evaluate the efficacy and safety of hormonal and synchronous docetaxel plus prednisone (DocP) in metastatic hormone-sensitive prostate cancer (mHSPC).

Methods

One hundred fifty-one cases with high-burden mHSPC diagnosed at 1 single center from January 2014 to August 2018 were analyzed retrospectively. Among them, 85 cases received androgen-deprivation therapy (ADT) within 3 months, along with 6 cycles of docetaxel + prednisone (treatment group), whereas 66 received ADT alone (control group). The primary end point was the median overall survival (OS), while the secondary outcomes included prostate-specific antigen (PSA) progression-free survival (PFS), radiographic PFS, and the proportion of PSA falling to 0.2 ng/mL.

Results

A total of 151 patients were included and followed up for a median of 34 months in this study. The median OS time in the treatment group was unavailable, but it was remarkably longer than that of the control group (P<0.001). In addition, the PFS of PSA in the treatment group and control group was 17.9 months and 9.2 months, respectively (P<0.001). Meanwhile, the radiographic PFS was 43 months in the treatment group and 19.8 months in the control group, respectively (P<0.001). The proportions of PSA falling to 0.2 ng/mL were 53.7% and 23.3%, respectively (P<0.001). However, there was no significant difference in the incidence of ≥3 toxic side effects between these 2 groups (P=0. 21).

Conclusion

ADT combined with 6 cycles of docetaxel + prednisone chemotherapy benefits patients diagnosed with high-burden mHSPC in terms of the OS, PFS of PSA and radiographic, and the ratio of PSA falling to 0.2 ng/mL.

The management of patients with metastatic prostate cancer during the COVID-19 pandemic

During the ongoing global pandemic of coronavirus disease 2019 (COVID-19), the benefit of treating patients with cancer must be weighed against the COVID-19 infection risks to patients, staff and society. Prostate cancer is one of the most common cancers among men and raises particular interest during the pandemic as recent reports show that the TMPRSS2 (and other serine proteases), which facilitate the entry, replication and budding of the virion from a cell, can be inhibited using androgen deprivation therapy. Nevertheless, patients with metastatic prostate cancer commonly receive chemotherapy which may compromise their immune system. This paper aims to address the current status of the COVID-19 in patients with cancer overall and suggests an optimal approach to patients with metastatic prostate cancer.

The Evolution of Master Protocol Clinical Trial Designs: A Systematic Literature Review

PURPOSE

Recent years have seen a change in the way that clinical trials are being conducted. There has been a rise of designs more flexible than traditional adaptive and group sequential trials which allow the investigation of multiple substudies with possibly different objectives, interventions, and subgroups conducted within an overall trial structure, summarized by the term master protocol. This review aims to identify existing master protocol studies and summarize their characteristics. The review also identifies articles relevant to the design of master protocol trials, such as proposed trial designs and related methods.

METHODS

We conducted a comprehensive systematic search to review current literature on master protocol trials from a design and analysis perspective, focusing on platform trials and considering basket and umbrella trials. Articles were included regardless of statistical complexity and classified as reviews related to planned or conducted trials, trial designs, or statistical methods. The results of the literature search are reported, and some features of the identified articles are summarized.

FINDINGS

Most of the trials using master protocols were designed as single-arm (n = 29/50), Phase II trials (n = 32/50) in oncology (n = 42/50) using a binary endpoint (n = 26/50) and frequentist decision rules (n = 37/50). We observed an exponential increase in publications in this domain during the last few years in both planned and conducted trials, as well as relevant methods, which we assume has not yet reached its peak. Although many operational and statistical challenges associated with such trials remain, the general consensus seems to be that master protocols provide potentially enormous advantages in efficiency and flexibility of clinical drug development.

IMPLICATIONS

Master protocol trials and especially platform trials have the potential to revolutionize clinical drug development if the methodologic and operational challenges can be overcome.

Enzalutamide plus androgen-deprivation therapy in hormone-sensitive prostate cancer: new perspectives from a current Phase III clinical trial

Prostate cancer is a major health issue with an incidence of 1,100,000 worldwide. Eventually, 20-40% of curatively treated patients will face a biochemical recurrence. Lately, the treatment options in metastasized hormone sensitive prostate cancer (mHSPC) were rapidly evolving after years of stagnation. Encouraging results in clinical trials of combination treatment of androgen deprivation therapy with either chemotherapy or second-generation hormonal treatment indicate a paradigm shift in this clinical scenario. In the light of this, the current review is focusing on the concept and initial results of the Phase III (ARCHES) trial investigating enzalutamide plus androgen deprivation therapy in mHSPC. Moreover, a comprehensive appraisal of the expanding landscape of systemic therapies for mHSPC is provided.

Metastatic Hormone-Sensitive Prostate Cancer (mHSPC): Advances and Treatment Strategies in the First-Line Setting

The treatment landscape of metastatic hormone-sensitive prostate cancer (mHSPC) has changed radically in recent years. Androgen deprivation therapy (ADT) alone was for decades the standard of care for treating mHSPC. This changed when studies showed that the addition of docetaxel chemotherapy or abiraterone acetate to ADT significantly increases overall survival of patients with mHSPC, followed by more recent evidence showing the efficacy of androgen receptor antagonists, such as enzalutamide and apalutamide, in this setting. While this rapid therapeutic evolution is welcome, it presents clinicians with a crucial challenge: the choice of treatment selection and sequencing. In the first-line setting there are no comparative data currently available to guide treatment choice between the different available regimens, and no prospective data to guide clinical decision after progression. Decisions on treatment will now need to be personalised based on indirect comparison of the available efficacy data from multiple phase 3 studies, together with considerations of disease volume, comorbidities, treatment aims, toxicity profile and cost reimbursement within the healthcare setting. Here, we provide an overview of the clinical trial data to date and propose some biological and clinical insights which may be helpful in making decisions on treatment selection and sequencing.

Translating the Immunobiology of SBRT to Novel Therapeutic Combinations for Advanced Prostate Cancer

Stereotactic body radiotherapy (SBRT) is an increasingly used radiation modality for the treatment of both localized and metastatic prostate cancer. Substantial data suggests that prostate cancer may be more sensitive to higher doses of radiation per fraction due to its low α/β ratio. This increased sensitivity raises important questions as to how SBRT should be combined with systemic therapy for clinically significant prostate cancer, including whether androgen deprivation therapy retains its beneficial effects when combined with SBRT. Furthermore, pre-clinical and clinical data suggest pronounced immunomodulatory effects of SBRT, including observed improvements in T cell priming and trafficking. These data support investigational strategies combining SBRT with immunotherapy. Here we aim to review the data for the use of SBRT in both the local and metastatic disease settings as well as ongoing translational and clinical research examining combinations with ADT, immunotherapy and other targeted agents.

Latest progress in molecular biology and treatment in genitourinary tumours

The management of genitourinary cancer, including bladder, prostate, renal and testicular cancer, has evolved dramatically in recent years due to a better understanding of tumour genetic mutations, alterations in molecular pathways, and to the development of new kinds of drugs such as targeted therapies and immunotherapies. In the field of immunotherapy, new drugs focused on stimulating, enhancing and modulating the immune system to detect and destroy cancer, have been recently discovered. Research in oncology moves quickly and new data of great relevance for clinical practice are communicated every year. For this reason, a group of experts, focused exclusively on the treatment of genitourinary tumours and who get together every year in the BestGU conference to assess the latest progress in this field have summarized the most important advances in a single review, along with a critical assessment of whether these results should alter daily clinical practice.

Treatment with abiraterone and enzalutamide does not overcome poor outcome from metastatic castration-resistant prostate cancer in men with the germline homozygous HSD3B1 c.1245C genotype

BACKGROUND

In men with castration-sensitive prostate cancer (CSPC), the HSD3B1 c.1245A>C variant has been reported to be associated with shorter responses to first-line androgen-deprivation therapy (ADT). Here, we evaluated the association between the inherited HSD3B1 c.1245A>C variant and outcomes from metastatic castration-resistant prostate cancer (mCRPC) after first-line treatment with abiraterone (Abi) or enzalutamide (Enza).

PATIENTS AND METHODS

Patients with mCRPC (n = 266) were enrolled from two centers at the time of starting first-line Abi/Enza. Outcomes after Abi/Enza included best prostate-specific antigen (PSA) response, treatment duration, and overall survival (OS). Outcomes after first-line ADT were determined retrospectively, and included treatment duration and OS. As was prespecified, we compared patients with the homozygous variant HSD3B1 genotype (CC genotype) versus the combined group with the heterozygous (AC) and homozygous wild-type (AA) genotypes.

RESULTS

Among the 266 patients, 22 (8.3%) were homozygous for the HSD3B1 variant (CC). The CC genotype had no association with PSA response rate; the median Abi/Enza treatment duration was 7.1 months for the CC group and 10.3 months for the AA/AC group (log rank P = 0.34). Patients with the CC genotype had significantly worse OS, with median survival at 23.6 months for the CC group and 30.7 months for the AA/AC group (log rank P = 0.02). In multivariable analysis adjusting for age, Gleason score, PSA, prior chemotherapy, and M1 disease, the association between the CC genotype and OS remained significant (hazard ratio 1.78, 95% confidence interval 1.03-3.07, P = 0.04). Poor outcome after first-line ADT in the CC group was also observed when evaluating retrospective ADT duration data for the same combined cohort.

CONCLUSIONS

In this large two-center study evaluating the HSD3B1 c.1245 genotype and outcomes after first-line Abi/Enza, homozygous variant (CC) HSD3B1 genotype was associated with worse outcomes. Novel therapeutic strategies are needed to enable treatment selection based on this genetic marker.

Optimizing the role of androgen deprivation therapy in advanced prostate cancer: Challenges beyond the guidelines

BACKGROUND

For specific clinical indications, androgen deprivation therapy (ADT) will induce disease prostate cancer (PC) regression, relieve symptoms and prolong survival; however, ADT has a well-described range of side effects, which may have a detrimental effect on the patient's quality of life, necessitating additional interventions or changes in PC treatment. The risk-benefit analysis for initiating ADT in PC patients throughout the PC disease continuum warrants review.

METHODS

A 14-member panel comprised of urologic and medical oncologists were chosen for an expert review panel, to provide guidance on a more judicious use of ADT in advanced PC patients. Panel members were chosen based upon their academic and community experience and expertise in the management of PC patients. Four academic members of the panel served as group leaders; the remaining eight panel members were from Large Urology Group Practice Association practices with proven experience in leading their advanced PC clinics. The panel members were assigned to four separate working groups, and were tasked with addressing the role of ADT in specific PC settings.

RESULTS

This article describes the practical recommendations of an expert panel for the use of ADT throughout the PC disease continuum, as well as an algorithm summarizing the key recommendations. The target for this publication is all providers (urologists, medical oncologists, radiation oncologists, or advanced practice providers) who evaluate and manage advanced PC patients, regardless of their practice setting.

CONCLUSION

The panel has provided recommendations for monitoring PC patients while on ADT, recognizing that PC patients will progress despite testosterone suppression and, therefore, early identification of conversion from castrate-sensitive to castration resistance is critical. Also, the requirement to both identify and mitigate side effects of ADT as well as the importance of quality of life maintenance are essential to the optimization of patient care, especially as more combinatorial therapeutic strategies with ADT continue to emerge.

Lessons from the coronavirus disease 2019 pandemic: Will virtual patient management reshape uro-oncology in Germany?

The coronavirus disease 2019 (COVID-19) pandemic is challenging for physicians treating patients with genitourinary cancers as they are considered at high risk of severe events. The uro-oncology outpatient clinic at our academic institution was affected early by the outbreak owing to the widespread infection of healthcare personnel. Subsequently, we developed a strategy to ensure the patient's safety by efforts focused on strict quarantine observation, reduction of clinic visits and implementation of virtual patient management into the workflow. Furthermore, we analysed susceptibility to COVID-19 and its effects on patients with uro-oncological cancer treated with antitumoural agents. The goal is to warrant high-quality cancer care, despite being an academic centre on the front line of Germany's response to COVID-19.

Preliminary results of targeted prostate-specific membrane antigen imaging in evaluating the efficacy of a novel hormone agent in metastatic castration-resistant prostate cancer

To investigate the feasibility and effectiveness of prostate‐specific membrane antigen (PSMA) imaging to make response assessment regarding novel hormone treatment and to predict the outcomes for metastatic castration‐resistant prostate cancer (mCRPC) patients. This retrospective study enrolled 68 mCRPC patients who had daily received a novel hormone agent named abiraterone. Tc‐99m PSMA single‐photon emission computed tomography (SPECT/CT) was performed at the baseline (SPECT/CT1) and after 3‐6 months of treatment (SPECT/CT2). The treatment response was determined by visual analysis based on molecular imaging PSMA (miPSMA) scores framework and was compared with conventional biochemical analysis. We chose either the hottest lesion (target A) or five of the hottest lesions (target B) to calculate the tumor/background ratio (TBR) and the maximum standardized uptake value (SUVmax) and compared their performances in predicting progression‐free survival (PFS). Changes in PSMA expression between SPECT/CT1 and SPECT/CT2 were well associated with the results of the visual analysis. The TBR and the SUVmax of both targets were significantly associated with the baseline serum PSA level (P < .0001). The biochemical and radiological responses were concordant in 56 of the 68 patients (P < .001). The median PFS of the nonresponse group patients was significantly shorter than that of the patients in the response group (6.8 vs 12.1 months, P = .012). For predicting PFS, most of the indexes tested were significant on SPECT/CT2, with %ΔTBR being the most significant prognostic factor. Our preliminary results suggest that molecular imaging‐targeted PSMA is of great value for treatment response assessment and clinical outcome prediction in mCRPC patients with long‐term abiraterone treatment.

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

BACKGROUND

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

OBJECTIVE

To present the results from the APCCC 2019.

DESIGN, SETTING, AND PARTICIPANTS

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

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

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

RESULTS AND LIMITATIONS

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

CONCLUSIONS

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

PATIENT SUMMARY

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

Navigating systemic therapy for metastatic castration-naïve prostate cancer

INTRODUCTION

The last decade has seen a remarkable shift in the treatment landscape of advanced prostate cancer, none more so than in the management of metastatic castration-naïve disease.

METHODS

This narrative review will examine existing and emerging evidence supporting systemic therapy use for metastatic castration-naïve prostate cancer (mCNPC) and provide guidance on the selection of these agents with respect to optimising patient outcomes.

RESULTS

The addition of either docetaxel (chemohormonal approach) or an AR pathway inhibitor (abiraterone, enzalutamide or apalutamide) is a reasonable standard of care option for men commencing long-term ADT for mCNPC. While the issue of disease volume as a predictive biomarker for docetaxel benefit has previously been debated, recent data support consideration of upfront docetaxel in all patients, regardless of metastatic burden. Decisions regarding systemic treatment for men with mCNPC should be based on comprehensive consideration of disease, patient and logistical factors. Multiple novel therapeutics for mCNPC are currently under active investigation.

CONCLUSION

The introduction of potent systemic therapy earlier in the mCNPC disease course has resulted in dramatic improvements in clinical outcomes for patients. As the management of mCNPC continues to evolve, the future remains promising, with the expectation of ongoing improvements to patient outcomes and quality of life.

Current and Future Management of Locally Advanced and Metastatic Prostate Cancer

With increasing treatment options available, the management of locally advanced and metastatic prostate cancer (PCa) is growing more complex, nuanced, and individualized. Strategies for combining surgery, radiation, chemotherapy, and androgen deprivation therapy (ADT) continue to evolve, as do ADT and immunotherapy options. Additionally, multiple adjunctive agents for metastatic PCa have been recently approved or are pending approval. As the number of locally advanced and metastatic prostate cancers being diagnosed rises, so does the need to consider patients' clinical situations and personal preferences. This review discusses current and potential future approaches to managing locally advanced and metastatic PCa.

Treatment of Advanced Prostate Cancer

The therapeutic landscape of prostate cancer has been transformed over the last decade by new therapeutics, advanced functional imaging, next-generation sequencing, and better use of existing therapies in early-stage disease. Until 2004, progression on androgen deprivation therapy for metastatic disease was treated with the addition of secondary hormonal manipulation; in the last decade, six systemic agents have been approved for the treatment of castration-resistant prostate cancer. We review clinical trials and survival benefit for these therapies and assess how the understanding of the disease shifted as these therapies were developed. We also discuss advances in noncastrate disease states, identification of biomarkers for prognosis and treatment selection, and opportunities in locoregional therapy to delay androgen deprivation therapy.

Abiraterone in "High-" and "Low-risk" Metastatic Hormone-sensitive Prostate Cancer

BACKGROUND

Abiraterone acetate received licencing for use in only "high-risk" metastatic hormone-naïve prostate cancer (mHNPC) following the LATITUDE trial findings. However, a "risk"-related effect was not seen in the STAMPEDE trial. There remains uncertainty as to whether men with LATITUDE "low-risk" M1 disease benefit from androgen deprivation therapy (ADT) combined with abiraterone acetate and prednisolone (AAP).

OBJECTIVE

Evaluation of heterogeneity of effect between LATITUDE high- and low-risk M1 prostate cancer patients receiving ADT + AAP in the STAMPEDE trial.

DESIGN, SETTING, AND PARTICIPANTS

A post hoc subgroup analysis of the 2017 STAMPEDE "abiraterone comparison". Staging scans for M1 patients contemporaneously randomised to ADT or ADT + AAP within the STAMPEDE trial were evaluated centrally and blind to treatment assignment. Stratification was by risk according to the criteria set out in the LATITUDE trial. Exploratory subgroup stratification incorporated the CHAARTED criteria.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome measure was overall survival (OS) and the secondary outcome measure was failure-free survival (FFS). Further exploratory analysis evaluated clinical skeletal-related events, progression-free survival (PFS), and prostate cancer-specific death. Standard Cox-regression and Kaplan-Meier survival estimates were employed for analysis.

RESULTS AND LIMITATIONS

A total of 901 M1 STAMPEDE patients were evaluated after exclusions. Of the patients, 428 (48%) were identified as having a low risk and 473 (52%) a high risk. Patients receiving ADT + AAP had significantly improved OS (low-risk hazard ratio [HR]: 0.66, 95% confidence interval or CI [0.44-0.98]) and FFS (low-risk HR: 0.24, 95% CI [0.17-0.33]) compared with ADT alone. Heterogeneity of effect was not seen between low- and high-risk groups for OS or FFS. For OS benefit in low risk, the number needed to treat was four times greater than that for high risk. However, this was not observed for the other measured endpoints.

CONCLUSIONS

Men with mHNPC gain treatment benefit from ADT + AAP irrespective of risk stratification for "risk" or "volume".

PATIENT SUMMARY

Coadministration of abiraterone acetate and prednisolone with androgen deprivation therapy (ADT) is associated with prolonged overall survival and disease control, compared with ADT alone, in all men with metastatic disease starting hormone therapy for the first time.

Addition of docetaxel to hormonal therapy in low- and high-burden metastatic hormone sensitive prostate cancer: long-term survival results from the STAMPEDE trial

BACKGROUND

STAMPEDE has previously reported that the use of upfront docetaxel improved overall survival (OS) for metastatic hormone naïve prostate cancer patients starting long-term androgen deprivation therapy. We report on long-term outcomes stratified by metastatic burden for M1 patients.

METHODS

We randomly allocated patients in 2 : 1 ratio to standard-of-care (SOC; control group) or SOC + docetaxel. Metastatic disease burden was categorised using retrospectively-collected baseline staging scans where available. Analysis used Cox regression models, adjusted for stratification factors, with emphasis on restricted mean survival time where hazards were non-proportional.

RESULTS

Between 05 October 2005 and 31 March 2013, 1086 M1 patients were randomised to receive SOC (n = 724) or SOC + docetaxel (n = 362). Metastatic burden was assessable for 830/1086 (76%) patients; 362 (44%) had low and 468 (56%) high metastatic burden. Median follow-up was 78.2 months. There were 494 deaths on SOC (41% more than the previous report). There was good evidence of benefit of docetaxel over SOC on OS (HR = 0.81, 95% CI 0.69-0.95, P = 0.009) with no evidence of heterogeneity of docetaxel effect between metastatic burden sub-groups (interaction P = 0.827). Analysis of other outcomes found evidence of benefit for docetaxel over SOC in failure-free survival (HR = 0.66, 95% CI 0.57-0.76, P < 0.001) and progression-free survival (HR = 0.69, 95% CI 0.59-0.81, P < 0.001) with no evidence of heterogeneity of docetaxel effect between metastatic burden sub-groups (interaction P > 0.5 in each case). There was no evidence that docetaxel resulted in late toxicity compared with SOC: after 1 year, G3-5 toxicity was reported for 28% SOC and 27% docetaxel (in patients still on follow-up at 1 year without prior progression).

CONCLUSIONS

The clinically significant benefit in survival for upfront docetaxel persists at longer follow-up, with no evidence that benefit differed by metastatic burden. We advocate that upfront docetaxel is considered for metastatic hormone naïve prostate cancer patients regardless of metastatic burden.

WHO SHOULD RECEIVE RADIOTHERAPY IN METASTATIC HORMONE-SENSITIVE PROSTATE CANCER?

The standard of treatment of metastatic hormone-sensitive prostate cancer (mHSPC) is androgen deprivation therapy (ADT) with docetaxel or abiraterone. However, numerous retrospective studies suggested outcome benefit of prostate radiotherapy. Small randomized trial (HORRAD) showed no overall survival (OS) benefit of the addition of prostate radiotherapy to ADT but there was a trend toward survival benefit in a low volume disease. Although the results of large randomized study (STAMPEDE) have also not proved improvement of OS in unselected patients, robust improvement of failure-free survival was found. In addition, OS was significantly improved in patients with a low volume disease. In the absence of reliable molecular markers, the extent of metastatic disease has emerged as an important factor for treatment decision making. In this review, we summarize data from non-randomized as well as from randomized studies concerning prostate radiotherapy to contribute to the improvement of treatment tailoring for each individual patient with mHSPC in order to achieve the best possible treatment outcomes.

Management of advanced prostate cancer in Hong Kong: Insights from an APCCC-Derived survey

AIM

The 2017 Advanced Prostate Cancer Consensus Conference (APCCC) convened an international multidisciplinary panel to vote on controversial issues in the management of advanced prostate cancer (APC). We aimed to compare their conclusions with the opinions of local specialists and explore the practicability of international recommendations in the healthcare setting in Hong Kong.

METHODS

Urologists and clinical oncologists practicing in Hong Kong were invited to complete a survey based on the original APCCC 2017 questionnaire and recently published trials in APC. A joint committee of expert key opinion leaders was convened to discuss and analyze the voting differences between local specialists and the APCCC 2017 panel.

RESULTS

The respondents constituted 21% (28/132) of registered urologists and 21% (31/146) of clinical oncologists in Hong Kong. Discrepancies in three key areas were identified as being the most timely for this analysis: (a) management of metastatic hormone-sensitive/naïve prostate cancer; (b) management of metastatic castration-resistant prostate cancer; and (c) treatment monitoring and initiation of androgen-deprivation therapy. Fears of toxicity and intolerance among patients and physicians (especially urologists) may be driving the relative underuse of chemotherapy in multiple APC patient groups in Hong Kong. Local patients can face long wait times and limited access to contemporary imaging modalities compared with other developed countries.

CONCLUSION

Increased collaborative efforts by urologists and clinical oncologists could ensure that patients gain wider access to the latest diagnostic, treatment and monitoring modalities for APC in Hong Kong.

[Docetaxel or abiraterone in combination with androgen deprivation therapy for metastatic prostate cancer]

BACKGROUND

Androgen deprivation therapy (ADT) alone has long been the standard of care in the treatment of metastatic prostate cancer (mCSPC). A paradigm shift in the treatment of patients with mCSPC has now been initiated by the results of three major phase 3 clinical trials (CHAARTED, STAMPEDE, LATITUDE): They demonstrated a significant advantage of ADT in combination with docetaxel or abiraterone/prednisone over ADT alone.

OBJECTIVES

This review presents the current evidence for the use of docetaxel or abiraterone/prednisone in combination with ADT and discusses-in the absence of directly comparing studies-which patients may have an advantage of ADT plus abiraterone/prednisone over ADT plus docetaxel or vice versa.

METHODS

A systematic review based on bibliographic literature search was conducted.

RESULTS

Both the combinations of ADT with docetaxel and with abiraterone/prednisone represent a major advance in the treatment of patients with mCSPC, in particular of patients with multiple metastases. Compared to chemotherapy, the use of abiraterone in addition to ADT avoids (rare) neutropenic complications and treatment-associated deaths. Long-term oral treatment with abiraterone/prednisone as a complementary therapy to ADT replaces short-term intravenous treatment (docetaxel).

CONCLUSION

In patients with mCSPC, ADT plus docetaxel or ADT plus abiraterone/prednisone is recommended. In particular in patients with pre-existing cardiovascular disease, ADT should be considered with a GnRH (gonadotropin-releasing hormone) antagonist to reduce the risk of cardiotoxic side effects.

The Evolving Systemic Treatment Landscape for Patients with Advanced Prostate Cancer

Prostate cancer (PC) is a major health issue in developed countries, with, on the one hand, men suffering from sequelae related to unnecessary treatment of non-lethal PC, and, on the other hand, still dying because of advanced PC that progresses to castration-resistant disease. Systemic treatment is the mainstay of therapy of castration-resistant PC (CRPC). To date, a multitude of systemic agents have been tested and many of these have failed to provide a clinically meaningful benefit in CRPC, while others have been approved by the US Food and Drug Administration and/or the European Medicines Agency, including antiandrogen hormonal drugs (abiraterone, enzalutamide, apalutamide), chemotherapy (docetaxel and cabazitaxel), immunotherapy (Sipuleucel-T), and radiopharmaceutical (Radium-223) agents. In this review, systemic treatments regarded as most likely to have an impact in clinical practice are presented and discussed. In addition to the pivotal clinical studies, selected retrospective and non-randomized clinical trials are also discussed if deemed to have an impact on clinical practice or future research. A comprehensive appraisal of the expanding landscape of systemic therapies for advanced PC is provided from an expert perspective, with a focus on novel classification and diagnostic tools that have been paving the way for the development of precision medicine in PC.

Novel treatment options in the management of metastatic castration-naïve prostate cancer; which treatment modality to choose?

Androgen-deprivation therapy (ADT) has been the mainstay of treatment of metastatic prostate cancer since the first report of its hormonal dependence in the 1940s. Since 2015, the addition of docetaxel and the addition of abiraterone to ADT have conferred substantial overall survival benefit in men with metastatic castration-naïve prostate cancer (mCNPC). The shift of these treatment options for metastatic prostate cancer from the castration-resistant setting to the castration-naïve setting has led to new challenges in the management of this disease. It remains to be determined which patients may benefit most from either early concomitant docetaxel or from abiraterone with ADT, since biomarkers for early therapy response and risk stratification are currently lacking. Therefore, the ability to personalize medicine is hampered. Furthermore, the earlier detection of metastatic prostate cancer by using new imaging modalities makes the application of clinical trial results in daily practice increasingly challenging. Recently, both local radiotherapy to the primary tumor combined with ADT and abiraterone combined with ADT showed a survival benefit in low-volume disease patients. The latest data also demonstrated a survival benefit with the addition of apalutamide or enzalutamide to ADT. The extent of metastatic disease may become one of the most important factors to determine treatment choice. In this review article, we summarize trial data to provide guidance for treatment selection in metastatic castration-naïve prostate cancer.

The Potential for Chemotherapy-Free Strategies in Advanced Prostate Cancer

The treatment landscape for advanced prostate cancer is evolving rapidly, with new agents and strategies, and more optimal use of existing therapies under constant development. Efforts were focused on better understanding of the biology of the disease. This effort has paved the way for a more contemporary and effective therapies to be developed. There are now 6 FDA-approved therapies that increase overall survival. These include the immunotherapy sipuleucel-T; the 2 androgen pathway inhibitors: abiraterone acetate and enzalutamide; 2 chemotherapy drugs: docetaxel and cabazitaxel; and the radionuclide: radium-223. Advanced prostate cancer may be one of the few cancers for which multiple chemotherapy and nonchemotherapy regimens are considered as standard. Several recently published clinical trials have demonstrated the suprising activity of chemotherapy-free strategies, and we should not be too eager to discount these "old-fashioned" treatments. Optimal sequencing is still unclear because new therapies have proliferated so quickly that comparative data are limited. In this short communication, we identify current challenges and unmet needs in advanced prostate cancer and provide an overview of their respective clinical activity, while highlighting distinctions between therapies.

Systematic review of basket trials, umbrella trials, and platform trials: a landscape analysis of master protocols

BACKGROUND

Master protocols, classified as basket trials, umbrella trials, and platform trials, are novel designs that investigate multiple hypotheses through concurrent sub-studies (e.g., multiple treatments or populations or that allow adding/removing arms during the trial), offering enhanced efficiency and a more ethical approach to trial evaluation. Despite the many advantages of these designs, they are infrequently used.

METHODS

We conducted a landscape analysis of master protocols using a systematic literature search to determine what trials have been conducted and proposed for an overall goal of improving the literacy in this emerging concept. On July 8, 2019, English-language studies were identified from MEDLINE, EMBASE, and CENTRAL databases and hand searches of published reviews and registries.

RESULTS

We identified 83 master protocols (49 basket, 18 umbrella, and 16 platform trials). The number of master protocols has increased rapidly over the last five years. Most have been conducted in the US (n = 44/83) and investigated experimental drugs (n = 82/83) in the field of oncology (n = 76/83). The majority of basket trials were exploratory (i.e., phase I/II; n = 47/49) and not randomized (n = 44/49), and more than half (n = 28/48) investigated only a single intervention. The median sample size of basket trials was 205 participants (interquartile range, Q3-Q1 [IQR]: 500-90 = 410), and the median study duration was 22.3 (IQR: 74.1-42.9 = 31.1) months. Similar to basket trials, most umbrella trials were exploratory (n = 16/18), but the use of randomization was more common (n = 8/18). The median sample size of umbrella trials was 346 participants (IQR: 565-252 = 313), and the median study duration was 60.9 (IQR: 81.3-46.9 = 34.4) months. The median number of interventions investigated in umbrella trials was 5 (IQR: 6-4 = 2). The majority of platform trials were randomized (n = 15/16), and phase III investigation (n = 7/15; one did not report information on phase) was more common in platform trials with four of them using seamless II/III design. The median sample size was 892 (IQR: 1835-255 = 1580), and the median study duration was 58.9 (IQR: 101.3-36.9 = 64.4) months.

CONCLUSIONS

We anticipate that the number of master protocols will continue to increase at a rapid pace over the upcoming decades. More efforts to improve awareness and training are needed to apply these innovative trial design methods to fields outside of oncology.

Current Treatment Options for Metastatic Hormone-Sensitive Prostate Cancer

The possible treatments options for metastatic hormone-sensitive prostate cancer (mHSPC) have dramatically increased during the last years. The old backbone, which androgen-deprivation therapy (ADT) is the exclusive approach for hormone-naïve patients, has been disrupted. Despite the fact that several high-quality, randomized, controlled phase 3 trials have been conducted in this setting, no direct comparison is currently available among the different strategies. Inadequate power, absence of preplanning and small sample size frequently affect the subgroup analyses according to disease volume or patient's risk. The choice between ADT alone and ADT combined with docetaxel, abiraterone acetate, enzalutamide, apalutamide or radiotherapy to the primary tumor remains challenging. Factors that are related to the tumor, patient or drug side effects, currently guide these clinical decisions. This comprehensive review aims to indirectly compare the phase 3 trials in the mHSPC setting, in order to extrapolate data useful for treatment selection, providing also perspectives on future biomarkers.