Apalutamide plus abiraterone acetate and prednisone versus placebo plus abiraterone and prednisone in metastatic, castration-resistant prostate cancer (ACIS): a randomised, placebo-controlled, double-blind, multinational, phase 3 study

Systemic and Tumor-directed Therapy for Oligorecurrent Metastatic Prostate Cancer (SATURN): Primary Endpoint Results from a Phase 2 Clinical Trial

Nearly all men with metastatic hormone-sensitive prostate cancer treated with intermittent androgen deprivation therapy (ADT) experience recurrence within 6 mo of testosterone recovery. We conducted a single-arm phase 2 trial to evaluate whether addition of dual androgen receptor pathway inhibitors (ARPIs) and metastasis-directed stereotactic body radiotherapy (SBRT) to intermittent ADT improves recurrence rates for men with between one and five nonvisceral, extrapelvic metastases on prostate-specific membrane antigen positron emission tomography/computed tomography after prior radical prostatectomy. Patients received 6 mo of androgen annihilation therapy (AAT; leuprolide, abiraterone acetate plus prednisone, and apalutamide) and metastasis-directed SBRT. The primary endpoint was the percentage of patients with prostate-specific antigen (PSA) <0.05 ng/ml 6 mo after testosterone recovery (≥150 ng/dl), with the study powered to detect an improvement from 1% to 12%. We enrolled 28 men between March 2021 and June 2022. Median follow-up was 20 mo (interquartile range 16-22). Twenty-six patients (93%) completed SBRT with 6 mo of hormone therapy, of whom six discontinued at least one ARPI; two patients withdrew prematurely. At 6 mo after testosterone recovery, PSA was maintained at <0.05 ng/ml in 13/26 patients (50%, 95% confidence interval 32-67%). Rates of grade 2 and 3 AAT toxicity were 21% and 21%. The results confirm that addition of metastasis-directed SBRT to highly potent systemic therapy can maintain low PSA after testosterone recovery, although further studies are needed to clarify the optimal systemic therapy regimen. PATIENT SUMMARY: We tested a combination of intensified hormone therapy (called androgen annihilation therapy) and radiotherapy targeted at metastases in men with recurrence of metastatic prostate cancer. We found that half of patients were recurrence-free 6 months after their testosterone level recovered, and that less than a quarter of patients experienced a severe drug-related side effect. Overall, this appears to be an effective therapy with acceptable side effects. This trial is registered on ClinicalTrials.gov as NCT03902951.

From biology to the clinic - exploring liver metastasis in prostate cancer

Liver metastases from prostate cancer are associated with an aggressive disease course and poor prognosis. Results from autopsy studies indicate a liver metastasis prevalence of up to 25% in patients with advanced prostate cancer. Population data estimate that ~3-10% of patients with metastatic castration-resistant prostate cancer harbour liver metastases at the baseline, rising to 20-30% in post-treatment cohorts, suggesting that selective pressure imposed by novel therapies might promote metastatic spread to the liver. Liver metastases are associated with more aggressive tumour biology than lung metastases. Molecular profiling of liver lesions showed an enrichment of low androgen receptor, neuroendocrine phenotypes and high genomic instability. Despite advancements in molecular imaging modalities such as prostate-specific membrane antigen PET-CT, and liquid biopsy markers such as circulating tumour DNA, early detection of liver metastases from prostate cancer remains challenging, as both approaches are hampered by false positive and false negative results, impeding the accurate identification of early liver lesions. Current therapeutic strategies showed limited efficacy in this patient population. Emerging targeted radionuclide therapies, metastasis-directed therapy, and novel systemic agents have shown preliminary activity against liver metastases, but require further validation. Treatment with various novel prostate cancer therapies might lead to an increase in the prevalence of liver metastasis, underscoring the urgent need for coordinated efforts across preclinical and clinical researchers to improve characterization, monitoring, and management of liver metastases from prostate cancer. Elucidating molecular drivers of liver tropism and interactions with the liver microenvironment might ultimately help to identify actionable targets to enhance survival in this high-risk patient group.

Evaluating first-line therapeutic strategies for metastatic castration-resistant prostate cancer: a comprehensive network meta-analysis and systematic review

Objective

This study aimed to evaluate the relative efficacy and safety of first-line treatment options for metastatic castration-resistant prostate cancer (mCRPC).

Methods

We systematically searched electronic databases, including PubMed and Web of Science, for studies published from their inception to April 3rd, 2023. Inclusion criteria were: 1) Completed Phase III or IV randomized controlled trials (RCTs) registered on ClinicalTrials.gov; 2) Patients with a confirmed diagnosis of mCRPC who had not previously received chemotherapy or novel endocrine therapies. We conducted a network meta-analysis using R software (version 3.4.0). Network graphs and risk of bias graphs were generated using Stata 14.0 and RevMan 5.4, respectively. The primary outcome was overall survival (OS), and the secondary outcome was the incidence of severe adverse events (SAEs).

Results

Seven RCTs encompassing 6,641 patients were included. The network meta-analysis revealed that both docetaxel+prednisone (DP) and cabazitaxel+prednisone (CP) significantly improved OS compared to abiraterone. Compared to placebo, DP showed comparable results to both cabazitaxel 20 mg/m^2+prednisone (C20P) and cabazitaxel 25 mg/m^2+prednisone (C25P) in terms of OS. For SAEs, both DP and C20P were superior to C25P, with no statistical difference between C20P and DP. The probability ranking plots indicated that C25P ranked highest for OS, while DP ranked highest for SAEs.

Conclusions

Based on our network meta-analysis, we recommend cabazitaxel 20 mg/m^2+prednisone (C20P) as the primary choice for first-line management of mCRPC, followed by DP. Enzalutamide and abiraterone are suggested as subsequent options. Radium-223 may be considered for patients presenting with bone metastases.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023443943.

Cardiovascular Toxicity Associated With Androgen Receptor Axis-Targeted Agents in Patients With Prostate Cancer: A Meta-analysis of Randomized Controlled Trials

INTRODUCTION

Second-generation androgen receptor axis-targeting (ARAT) agents have become a standard treatment for patients with advanced prostate cancer (PC), however much remains unknown about the potential cardiovascular toxicities.

PATIENTS AND METHODS

We performed a systematic search of PubMed, Embase, Web of Science, and Cochrane library for randomized controlled trials of patients receiving ARAT agents for PC from inception to March 2023. The odds ratios (ORs) of all-grade and high-grade cardiovascular adverse events (CVAEs) for patients treated with and without ARAT agents were pooled for meta-analysis. Subgroup analyses based on PC type and treatment regimen were conducted.

RESULTS

A total of 15 double-blind placebo-controlled phase 3 trials comprising 15,842 patients were included. In addition to hot flush and hypertension of any degree of severity, inclusion of ARAT agents was associated with a significantly higher risk of acute myocardial infarction (OR: 1.96, 95% CI: 1.05-3.68, P = .04), myocardial infarction (OR: 2.44, 95% CI: 1.27-4.66, P = .007) and angina pectoris (OR: 2.00, 95% CI: 1.00-4.02, P = .05). With regard to individual ARAT agents, enzalutamide was associated with a significantly higher risk of acute myocardial infarction (OR: 3.11, 95% CI: 1.17-8.28, P = .02), coronary artery disease (OR: 8.33, 95% CI: 1.54-44.95, P = .01), and high-grade hypertension (OR: 4.94, 95% CI: 1.11-22.06, P = .04), while abiraterone and apalutamide were associated with a significantly higher risk of angina pectoris (OR: 5.48, 95% CI: 1.23-24.33, P = .03) and myocardial infarction (OR: 7.00, 95% CI: 1.60-30.62, P = .01), respectively.

CONCLUSION

The inclusion of ARAT agents was associated with a significantly higher risk of several CVAEs. Clinicians should remain vigilant, both in pre-treatment screening and monitoring for clinical symptoms and signs, when considering ARAT agent particularly for patients with pre-existing risk factors.

Stereotactic body radiation therapy to postpone systemic therapy escalation for castration-resistant prostate cancer: A multicenter retrospective analysis

Purpose

To evaluate the oncological outcome after stereotactic body radiation therapy (SBRT) for oligoprogressive metastatic castration-resistant prostate cancer (omCRPC) patients.

Materials-Methods

In this retrospective, observational, multi-institutional study, omCRPC patients (≤5 metastases) underwent SBRT. Primary endpoint was systemic therapy escalation-free survival (STE-FS) after SBRT. Local relapse (LR), distant (DP) and isolated biochemical (iBP) progressions were reported with progression-free survival (PFS) and overall survival (OS). Prognostic factors for STE-FS were investigated. Toxicity was reported.

Results

From 01/07 to 09/19, 50 pts with omCRPC underwent SBRT. With a MFU of 23 months [3---100], median STE-FS was 13.1 months (95 %CI 10.8 - 36.4). Median OS was not reached and PFS was 13 months (CI95% 10.1 - 20.8). Post-SBRT PSA remained stable or decreased in 19 pts (38 %). Progression events (LR, DP, iBP) were observed in 34 pts (68 %), among whom 6 relapsed in the irradiated area (local control rate: 88 %). DP and iBP were observed in 28 pts (56 %) and 4 pts (8 %) respectively. In multivariate analysis, post-SBRT biochemical response was an independent prognostic factor for STE-FS. Grade ≥ 3 toxicity occurred in 2 pts.

Conclusion

With excellent local control and tolerance, SBRT for omCRPC patients represents an acceptable approach to defer systemic therapeutic escalation and prevent its side effects. Accurate patient selection for SBRT requires more data with longer follow-up and higher numbers of patients pending the results of upcoming randomized trials.

Lysine methyltransferase SMYD2 enhances androgen receptor signaling to modulate CRPC cell resistance to enzalutamide

Androgen receptors (ARs) play key roles in prostate cancer (PCa) progression and castration-resistant prostate cancer (CRPC) resistance to drug therapy. SET and MYND domain containing protein 2 (SMYD2), a lysine methyltransferase, has been reported to promote tumors by transcriptionally methylating important oncogenes or tumor repressor genes. However, the role of SMYD2 in CRPC drug resistance remains unclear. In this study, we found that SMYD2 expression was significantly upregulated in PCa tissues and cell lines. High SMYD2 expression indicated poor CRPC-free survival and overall survival in patients. SMYD2 knockdown dramatically inhibited the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) potential of 22Rv1 and C4-2 cells. Conversely, ectopic overexpression of SMYD2 promoted these effects in 22Rv1 and C4-2 cells. Mechanistically, SMYD2 methylated and phosphorylated ARs to affect AR ubiquitination and proteasome degradation, which further alters the AR transcriptome in CRPC cells. Importantly, the SMYD2 inhibitor AZ505 had a synergistic therapeutic effect with enzalutamide in CRPC cells and mouse models; however, it could also re-sensitize resistant CRPC cells to enzalutamide. Our findings demonstrated that SMYD2 enhances the methylation and phosphorylation of ARs and affects AR ubiquitination and proteasome degradation to modulate CRPC cell resistance to enzalutamide, indicating that SMYD2 serves as a crucial oncogene in PCa and is an ideal therapeutic target for CRPC.

Heterogeneity of Radiological Progression Patterns and Association with Outcomes in Patients with Metastatic Prostate Cancer

BACKGROUND

With an increasing number of clinical trials using radiographic progression-free survival (rPFS) instead of overall survival as the primary study endpoint, the heterogeneity of different radiological progression patterns in rPFS and postprogression survival (PPS) remains unclear.

OBJECTIVE

Herein, we investigate the proportion of various radiological progression patterns in patients with metastatic hormone-sensitive prostate cancer (mHSPC) and metastatic castration-resistant prostate cancer (mCRPC), and further explore the differences in rPFS and PPS between patients exhibiting single- or multicategory progression patterns.

DESIGN, SETTING, AND PARTICIPANTS

This post hoc, retrospective secondary analysis was based on individual patient data from LATITUDE (phase 3 randomized mHSPC study) and COU-AA-302 (phase 3 randomized mCRPC study). Patients with complete imaging follow-up data and radiological progression were included in the analysis.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The rPFS and PPS in LATITUDE and COU-AA-302 were evaluated. The proportion of patients exhibiting each progression pattern was calculated, and a survival analysis was conducted using the Kaplan-Meier method.

RESULTS AND LIMITATIONS

Of the 489 mHSPC patients studied, 366 experienced single-category progression, while the remaining 123 patients (25.2%) exhibited simultaneous occurrence of different progressive events (multicategory radiological progression). Of the 534 mCRPC patients studied, 390 experienced single-category progression, while the remaining 144 patients (27.0%) experienced multicategory progressive events. Among mCRPC patients, the rPFS of bone progression was the shortest. In contrast, among mHSPC patients, the rPFS of target lesion enlargement is the shortest, followed by bone progression. Notably, patients experiencing a single-category progression pattern displayed comparable rPFS to but significantly longer PPS than those experiencing multicategory progression patterns (PPS mHSPC cohort: 21.5 vs 6.9 mo, p < 0.0001; mCRPC cohort: 23.6 vs 15.7 mo, p < 0.0001). The study is limited by its hypothesis-generating nature. Therefore, the observed phenomena in our research necessitate validation through future prospective studies.

CONCLUSIONS

Patients who experience multicategory radiological progression represent a significant proportion, accounting for approximately 25% of all men with mHSPC or mCRPC. Patients with multicategory radiological progression patterns had similar rPFS to but significantly shorter PPS than those experiencing single-category progression patterns. In future clinical trials and clinical practice, radiological progression patterns should be recognized as a crucial determinant of prognosis, while also serving as the stratification or inclusion criteria for second-line treatment clinical trials.

PATIENT SUMMARY

In this study, we observed that among men with metastatic prostate cancer, those who experienced two or more radiological events during a single visit had a worse prognosis than those who experienced isolated radiological events.

Major adverse cardiovascular events of enzalutamide versus abiraterone in prostate cancer: a retrospective cohort study

BACKGROUND

While the cardiovascular risks of androgen receptor pathway inhibitors have been studied, they were seldom compared directly. This study compares the risks of major adverse cardiovascular events (MACE) between enzalutamide and abiraterone among prostate cancer (PCa) patients.

METHODS

Adult PCa patients receiving either enzalutamide or abiraterone in addition to androgen deprivation therapy in Hong Kong between 1 December 1999 and 31 March 2021 were identified in this retrospective cohort study. Patients who switched between enzalutamide and abiraterone, initiated abiraterone used without steroids, or experienced prior cardiac events were excluded. Patients were followed-up until 30 September 2021. The primary outcomes were MACE, a composite of stroke, myocardial infarction (MI), Heart failure (HF), or all-cause mortality and a composite of adverse cardiovascular events (CACE) not including all-cause mortality. The secondary outcomes were individual components of MACE. Inverse probability treatment weighting was used to balance covariates between treatment groups.

RESULTS

In total, 1015 patients were analyzed (456 enzalutamide users and 559 abiraterone users; mean age 70.6 ± 8.8 years old) over a median follow-up duration of 11.3 (IQR: 5.3-21.3) months. Enzalutamide users had significantly lower risks of 4P-MACE (weighted hazard ratio (wHR) 0.71 [95% confidence interval (CI) 0.59-0.86], p < 0.001) and CACE (wHR 0.63 [95% CI: 0.42-0.96], p = 0.031), which remained consistent in multivariable analysis. Such an association may be stronger in patients aged ≥65 years or without diabetes mellitus and was independent of bilateral orchidectomy. Enzalutamide users also had significantly lower risks of MI (wHR 0.57 [95% CI: 0.33-0.97], p = 0.040) and all-cause mortality (wHR 0.71 [95% CI: 0.59-0.85], p < 0.001).

CONCLUSION

Enzalutamide was associated with lower cardiovascular risks than abiraterone in PCa patients.

Progression-free survival, disease-free survival and other composite end points in oncology: improved reporting is needed

Composite outcome measures such as progression-free survival and disease-free survival are increasingly used as surrogate end points in oncology research, frequently serving as the primary end point of pivotal trials that form the basis for FDA and EMA approvals. Such outcome measures combine two or more distinct events (for example, tumour (re)growth, new lesions and/or death) into a single, time-to-event end point. The use of a composite end point can increase the statistical power of a clinical trial and decrease the follow-up period required to demonstrate efficacy, thus lowering costs; however, these end points have a number of limitations. Composite outcomes are often vaguely defined, with definitions that vary greatly between studies, complicating comparisons of results across trials. Altering the makeup of events included in a composite outcome can alter study conclusions, including whether treatment effects are statistically significant. Moreover, the events included in a composite outcome often vary in clinical significance, reflect distinct biological pathways and/or are affected differently by treatment. Therefore, knowing the precise breakdown of the component events is essential to accurately interpret trial results and gauge the true benefit of an intervention. In oncology clinical trials, however, such information is rarely provided. In this Perspective, we emphasize this deficiency through a review of 50 studies with progression-free survival as an outcome published in five top oncology journals, discuss the advantages and challenges of using composite end points, and highlight the need for transparent reporting of the component events.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

DISCUSSION

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

Comparative efficacy of olaparib in combination with or without novel antiandrogens for treating metastatic castration-resistant prostate cancer

Background

Studies using novel antiandrogens (NAA) in patients with metastatic castration-resistant prostate cancer (mCRPC) have shown overall survival benefit. As patients develop resistance to NAA therapy, the poly(ADP-ribose) polymerase inhibitor (PARPi) olaparib in combination with NAA may become a promising therapy. However the overall benefit of olaparib monotherapy or combination therapy still needs to be evaluated. Therefore, we performed a network meta-analysis to assess the efficacy and toxicity between olaparib, olaparib combined with abiraterone and NAA.

Methods

We searched PubMed, EMBASE, the Cochrane Library and American Society of Clinical Oncology (ASCO) University Meeting abstracts for randomized controlled trials reporting olaparib and NAA from 2010 up to March, 2023. Network meta-analysis using Stata 16.0 and R 4.4.2, hazard ratios (HR) with 95% confidence intervals (CI) were used to assess the results.

Results

Four trials reported olaparib, olaparib plus abiraterone and apalutamide plus abiraterone. radiographic progression-free survival (rPFS) was significantly lower in patients on apalutamide plus abiraterone compared to olaparib (HR, 1.43; 95% CI, 1.06-1.93). rPFS was similar for olaparib plus abiraterone and olaparib (HR, 1.35; 95% CI, 0.99-1.84); likewise, olaparib plus abiraterone and apalutamide plus abiraterone were similar (HR, 1.06; 95% CI, 0.83-1.35). In addition, there was no significant difference between the three interventions for OS. But olaparib has the highest probability of being a preferred treatment for improving rPFS and OS.

Conclusion

rPFS was in favor of olaparib compared with apalutamide plus abiraterone. But there were no difference between olaparib plus abiraterone and either olaparib or apalutamide plus abiraterone. Apalutamide plus abiraterone might be the most preferred intervention in cases where AEs are involved.

Systematic review registration

https://inplasy.com, identifier INPLASY2023100072.

OCT4‑positive circulating tumor cells may predict a poor prognosis in patients with metastatic castration‑resistant prostate cancer treated with abiraterone plus prednisone therapy

Octamer-binding transcription factor 4 (OCT4) and circulating tumor cells (CTCs) are key factors associated with tumor metastasis and drug resistance in cancer. The present prospective study aimed to investigate the prevalence of OCT4-positive (OCT4+) CTCs and the potential association with the clinical features and survival of patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone + prednisone. In total, 70 patients with mCRPC treated with abiraterone + prednisone were enrolled in the present study and peripheral blood samples were collected prior to treatment initiation to determine CTC count via a Canpatrol system. RNA in situ hybridization was performed for OCT4+ CTC quantification. Lactate dehydrogenase (LDH) was detected by automatic biochemical analyzer (AU54000, OLYMPUS). Results demonstrated that 34 (48.6%), 21 (30.0%) and 15 (21.4%) patients harbored OCT4+ (CTC+/OCT4+) or OCT4-negative CTCs (CTC+/OCT4-) or were CTC-negative (CTC-), respectively. Notably, CTC+/OCT4+ occurrence was associated with visceral metastasis and high levels of LDH. In addition, radiographic progression-free survival [rPFS; median, 15.0, 95% confidence interval (CI), 9.6-20.4 vs. not reached vs. median, 29.5, 95% CI, 18.6-40.4 months; P=0.001] and overall survival (OS) were significantly decreased (median, 27.3, 95% CI, 20.1-34.5 vs. not reached vs. not reached; P=0.016) in CTC+/OCT4+ compared with CTC+/OCT4- and CTC- patients. Subsequently, the adjustment was performed by multivariate Cox regression models, which revealed that CTC+/OCT4+ (vs. CTC+/OCT4- or CTC-) was independently associated with decreased rPFS [hazard ratio (HR), 3.833; P<0.001] and OS (HR, 3.938; P=0.008). In conclusion, OCT4+ CTCs were highly prevalent in patients with mCRPC and associated with visceral metastasis and increased levels of LDH. Thus, the presence of OCT4+ CTCs may serve as an independent prognostic factor for patients with mCRPC treated with abiraterone + prednisone.

Systemic Therapies for Metastatic Castration-Resistant Prostate Cancer: An Updated Review

The introduction of novel therapeutic agents for advanced prostate cancer has led to a wide range of treatment options for patients with metastatic castration-resistant prostate cancer (mCRPC). In the past decade, new treatment options for mCRPC, including abiraterone, enzalutamide, docetaxel, cabazitaxel, sipuleucel-T, radium-223, 177Lu-PSMA-617, and Olaparib, have demonstrated a survival benefit in phase 3 trials. Bone-modifying agents have become part of the overall treatment strategy for mCRPC, in which denosumab and zoledronic acid reduce skeletal-related events. Recently, androgen receptor-signaling inhibitors (ARSIs) and docetaxel have been used upfront against metastatic castration-sensitive prostate cancer. Further, triplet therapy with ARSI, docetaxel, and androgen deprivation therapy is emerging. However, cross-resistance may occur between these treatments, and the optimal treatment sequence must be considered. The sequential administration of ARSIs, such as abiraterone and enzalutamide, is associated with limited efficacy; however, cabazitaxel is effective for patients with mCRPC who were previously treated with docetaxel and had disease progression during treatment with ARSI. Radioligand therapy with 177Lu-PSMA-617 is a new effective class of therapy for patients with advanced PSMA-positive mCRPC. Tumors with gene alterations that affect homologous recombination repair, such as BRCA1 and BRCA2 alterations, are sensitive to poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors in mCRPC. This review sought to highlight recent advances in systemic therapy for mCRPC and strategies to support patient selection and treatment sequencing.

An overview of hormonal directed pharmacotherapy for the treatment of prostate cancer

INTRODUCTION

Prostate cancer is the most common malignancy in the male. Androgen-deprivation therapy (ADT) has been the mainstay in the treatment of metastatic prostate cancer however, due to the outgrowth of castration-resistant cell population the disease inevitably progresses to an aggressive, difficult to handle stage.

AREAS COVERED

We have reviewed the literature regarding hormonal-directed therapy prostate cancer. New agents, namely abiraterone acetate, combined with prednisone, and next generation antiandrogens (enzalutamide, apalutamide and darolutamide) have shown considerable efficacy, not only in patients with metastatic but also in those with non-metastatic disease, either castration resistant (CRPC) or hormone sensitive (HSPC).

EXPERT OPINION

The addition of abiraterone and of the second-generation antiandrogens to our therapeutic armamentarium has improved prognosis ofprostate cancer in the last decade. Abiraterone is a viable option in patients with metastatic disease (hormone-sensitive and castration-resistant), whereas all next-generation antiandrogens have demonstrated efficacy in terms of metastasis-free and overall survival in non-metastatic CRPC. In addition, enzalutamide has also been found efficacious in mCRPC and mHSPC, while apalutamide in mHSPC. Currently there are no reliable data to indicate a potential superiority of one of these agents over the others in CRPC or HSPC as there are no relevant head to head studies . Sequencing hormone treatment modalities, chemotherapies and immunotherapies have not reached a consensus as yet. Randomized controlled trials are warranted to clearly define the role of novel antiandrogens in the treatment of prostate cancer. The choice of treatment should be individualized following discussion with the patient .

Randomized Phase III Study of Enzalutamide Compared With Enzalutamide Plus Abiraterone for Metastatic Castration-Resistant Prostate Cancer (Alliance A031201 Trial)

PURPOSE

Enzalutamide and abiraterone both target androgen receptor signaling but via different mechanisms. The mechanism of action of one drug may counteract the resistance pathways of the other. We sought to determine whether the addition of abiraterone acetate and prednisone (AAP) to enzalutamide prolongs overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC) in the first-line setting.

PATIENTS AND METHODS

Men with untreated mCRPC were randomly assigned (1:1) to receive first-line enzalutamide with or without AAP. The primary end point was OS. Toxicity, prostate-specific antigen declines, pharmacokinetics, and radiographic progression-free survival (rPFS) were also examined. Data were analyzed using an intent-to-treat approach. The Kaplan-Meier estimate and the stratified log-rank statistic were used to compare OS between treatments.

RESULTS

In total, 1,311 patients were randomly assigned: 657 to enzalutamide and 654 to enzalutamide plus AAP. OS was not statistically different between the two arms (median, 32.7 [95% CI, 30.5 to 35.4] months for enzalutamide v 34.2 [95% CI, 31.4 to 37.3] months for enzalutamide and AAP; hazard ratio [HR], 0.89; one-sided P = .03; boundary nominal significance level = .02). rPFS was longer in the combination arm (median rPFS, 21.3 [95% CI, 19.4 to 22.9] months for enzalutamide v 24.3 [95% CI, 22.3 to 26.7] months for enzalutamide and AAP; HR, 0.86; two-sided P = .02). However, pharmacokinetic clearance of abiraterone was 2.2- to 2.9-fold higher when administered with enzalutamide, compared with clearance values for abiraterone alone.

CONCLUSION

The addition of AAP to enzalutamide for first-line treatment of mCRPC was not associated with a statistically significant benefit in OS. Drug-drug interactions between the two agents resulting in increased abiraterone clearance may partly account for this result, although these interactions did not prevent the combination regimen from having more nonhematologic toxicity.

A real-world disproportionality analysis of apalutamide: data mining of the FDA adverse event reporting system

Background: Apalutamide is a new drug class, which is approved to treat prostate cancer (PCa). The aim of our study was to assess the safety profiles of apalutamide in real-world through data mining of the United States Food and Drug Administration Adverse Event Reporting System (FAERS). Method: We included adverse event (AE) reports regarding apalutamide submitted to the FAERS from 2018 quarter 1 (2018Q1) to 2022 quarter 1 (2022Q1). Disproportionality analyses, including reporting odds ratio (ROR), were performed to identify the signals of AEs in patients receiving apalutamide. A signal was detected if the lower limit of the 95% confidence interval (CI) of ROR >1 and at least 3 AEs were reported. Results: The FAERS database documented 4,156 reports regarding apalutamide from 1 January 2018, to 31 March 2022. A total of 100 significant disproportionality preferred terms (PTs) were retained. Frequently observed AEs in patients receiving apalutamide included rash, fatigue, diarrhea, hot flush, fall, weight decreased, hypertension. The most significant system organ class (SOC) was "skin and subcutaneous tissue disorders", which mainly consisted of dermatological adverse events (dAEs). The additional AEs observed with the significantly signal contain lichenoid keratosis, increased eosinophil count, bacterial pneumonia, pulmonary tuberculosis, hydronephrosis. Conclusion: Our findings provide valuable evidence for apalutamide safety profile in the real-world, which could help clinicians and pharmacists to enhance their vigilance and improve the safety of apalutamide in clinical practice.

External Validation of a Prognostic Model of Overall Survival in Men With Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer

PURPOSE

We have previously developed and externally validated a prognostic model of overall survival (OS) in men with metastatic, castration-resistant prostate cancer (mCRPC) treated with docetaxel. We sought to externally validate this model in a broader group of men with docetaxel-naïve mCRPC and in specific subgroups (White, Black, Asian patients, different age groups, and specific treatments) and to classify patients into validated two and three prognostic risk groupings on the basis of the model.

METHODS

Data from 8,083 docetaxel-naïve mCRPC men randomly assigned on seven phase III trials were used to validate the prognostic model of OS. We assessed the predictive performance of the model by computing the time-dependent area under the receiver operating characteristic curve (tAUC) and validated the two-risk (low and high) and three-risk prognostic groups (low, intermediate, and high).

RESULTS

The tAUC was 0.74 (95% CI, 0.73 to 0.75), and when adjusting for the first-line androgen receptor (AR) inhibitor trial status, the tAUC was 0.75 (95% CI, 0.74 to 0.76). Similar results were observed by the different racial, age, and treatment subgroups. In patients enrolled on first-line AR inhibitor trials, the median OS (months) in the low-, intermediate-, and high-prognostic risk groups were 43.3 (95% CI, 40.7 to 45.8), 27.7 (95% CI, 25.8 to 31.3), and 15.4 (95% CI, 14.0 to 17.9), respectively. Compared with the low-risk prognostic group, the hazard ratios for the high- and intermediate-risk groups were 4.3 (95% CI, 3.6 to 5.1; P < .0001) and 1.9 (95% CI, 1.7 to 2.1; P < .0001).

CONCLUSION

This prognostic model for OS in docetaxel-naïve men with mCRPC has been validated using data from seven trials and yields similar results overall and across race, age, and different treatment classes. The prognostic risk groups are robust and can be used to identify groups of patients for enrichment designs and for stratification in randomized clinical trials.

Abiraterone acetate plus prednisolone with or without enzalutamide for patients with metastatic prostate cancer starting androgen deprivation therapy: final results from two randomised phase 3 trials of the STAMPEDE platform protocol

BACKGROUND

Abiraterone acetate plus prednisolone (herein referred to as abiraterone) or enzalutamide added at the start of androgen deprivation therapy improves outcomes for patients with metastatic prostate cancer. Here, we aimed to evaluate long-term outcomes and test whether combining enzalutamide with abiraterone and androgen deprivation therapy improves survival.

METHODS

We analysed two open-label, randomised, controlled, phase 3 trials of the STAMPEDE platform protocol, with no overlapping controls, conducted at 117 sites in the UK and Switzerland. Eligible patients (no age restriction) had metastatic, histologically-confirmed prostate adenocarcinoma; a WHO performance status of 0-2; and adequate haematological, renal, and liver function. Patients were randomly assigned (1:1) using a computerised algorithm and a minimisation technique to either standard of care (androgen deprivation therapy; docetaxel 75 mg/m² intravenously for six cycles with prednisolone 10 mg orally once per day allowed from Dec 17, 2015) or standard of care plus abiraterone acetate 1000 mg and prednisolone 5 mg (in the abiraterone trial) orally or abiraterone acetate and prednisolone plus enzalutamide 160 mg orally once a day (in the abiraterone and enzalutamide trial). Patients were stratified by centre, age, WHO performance status, type of androgen deprivation therapy, use of aspirin or non-steroidal anti-inflammatory drugs, pelvic nodal status, planned radiotherapy, and planned docetaxel use. The primary outcome was overall survival assessed in the intention-to-treat population. Safety was assessed in all patients who started treatment. A fixed-effects meta-analysis of individual patient data was used to compare differences in survival between the two trials. STAMPEDE is registered with ClinicalTrials.gov (NCT00268476) and ISRCTN (ISRCTN78818544).

FINDINGS

Between Nov 15, 2011, and Jan 17, 2014, 1003 patients were randomly assigned to standard of care (n=502) or standard of care plus abiraterone (n=501) in the abiraterone trial. Between July 29, 2014, and March 31, 2016, 916 patients were randomly assigned to standard of care (n=454) or standard of care plus abiraterone and enzalutamide (n=462) in the abiraterone and enzalutamide trial. Median follow-up was 96 months (IQR 86-107) in the abiraterone trial and 72 months (61-74) in the abiraterone and enzalutamide trial. In the abiraterone trial, median overall survival was 76·6 months (95% CI 67·8-86·9) in the abiraterone group versus 45·7 months (41·6-52·0) in the standard of care group (hazard ratio [HR] 0·62 [95% CI 0·53-0·73]; p<0·0001). In the abiraterone and enzalutamide trial, median overall survival was 73·1 months (61·9-81·3) in the abiraterone and enzalutamide group versus 51·8 months (45·3-59·0) in the standard of care group (HR 0·65 [0·55-0·77]; p<0·0001). We found no difference in the treatment effect between these two trials (interaction HR 1·05 [0·83-1·32]; p_interaction=0·71) or between-trial heterogeneity (I² p=0·70). In the first 5 years of treatment, grade 3-5 toxic effects were higher when abiraterone was added to standard of care (271 [54%] of 498 vs 192 [38%] of 502 with standard of care) and the highest toxic effects were seen when abiraterone and enzalutamide were added to standard of care (302 [68%] of 445 vs 204 [45%] of 454 with standard of care). Cardiac causes were the most common cause of death due to adverse events (five [1%] with standard of care plus abiraterone and enzalutamide [two attributed to treatment] and one (<1%) with standard of care in the abiraterone trial).

INTERPRETATION

Enzalutamide and abiraterone should not be combined for patients with prostate cancer starting long-term androgen deprivation therapy. Clinically important improvements in survival from addition of abiraterone to androgen deprivation therapy are maintained for longer than 7 years.

FUNDING

Cancer Research UK, UK Medical Research Council, Swiss Group for Clinical Cancer Research, Janssen, and Astellas.

Emerging systemic treatment for metastatic castration-resistant prostate cancer: a review of recent randomized controlled trials

PURPOSE OF REVIEW

The landscape of therapy for metastatic castration-resistant prostate cancer (mCRPC) has seen an unprecedented transformation with the emergence of combination therapies. This review summarizes the current findings from randomized controlled trials (RCTs) assessing the oncologic outcomes of mCRPC.

RECENT FINDINGS

In the first-line, treatment-naïve setting, recent RCTs demonstrated the oncologic benefit of adding AKT inhibitors or poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors to abiraterone in terms of radiographical progression-free survival. Although this is a strong surrogate endpoint, these agents have not yet shown overall survival (OS) improvement. In the second- or later-line settings, olaparib improved OS in patients with at least one alteration in BRCA1 , BRCA2 , or ATM gene and lutetium-177-prostate-specific membrane antigen-617 [177-Lu-prostate-specific membrane antigen (PSMA)-617] were superior to repeat androgen receptor signaling inhibitor (ARSI) therapy. In addition, 177-Lu-PSMA-617 had better progression-free survival compared with cabazitaxel but failed to result in an OS benefit. To date, there is no evidence for effective immune checkpoint inhibitor regimens/combinations for mCRPC.

SUMMARY

According to recent RCTs, several novel agents and/or combinations exhibit promising oncologic outcomes. In the first-line setting, OS benefits compared with currently available regimens are still missing. Results from ongoing/well-designed phase 3 RCTs and real-world data regarding the sequential impact of currently available agents on outcomes of mCRPC patients after ARSI-based combination therapy for metastatic hormone-sensitive prostate cancer are awaited. Such data will improve clinical decision-making in the ever-intensifying treatment era.

Implications of metastatic stage at presentation in docetaxel naïve metastatic castrate resistant prostate cancer

BACKGROUND

We performed a secondary analysis of ACIS study to determine if synchronous versus metachronous metastatic presentation has any association with survival and treatment response to dual androgen receptor axis-targeted therapy (ARAT) in docetaxel naïve metastatic castrate resistant prostate cancer (mCRPC).

METHODOLOGY

In this phase III randomized controlled trial, docetaxel naïve mCRPC patients were randomized to either apalutamide or placebo combined with abiraterone and prednisone. Multivariable Cox regression models were applied to determine the adjusted association of M-stage with radiographic progression-free survival (rPFS) and overall survival (OS). To determine the heterogeneity of treatment effect based on metastatic stage (M-stage) at presentation, Cox regression was applied with interaction terms between M-stage and treatment.

RESULTS

Among 972 patients, 432 had M0, 334 had M1, while M-stage at presentation was unknown in 206. There was no association of M-stage at presentation with rPFS in patients with prior local therapy (LT) (hazard ratio for M1-stage: 1.22 [95% confidence interval: 0.82-1.82]; unknown: 1.03 [0.77-1.38]) or without prior LT (M1-stage: 0.87 [0.64-1.19]; unknown: 1.15 [0.77-1.72]) with no significant heterogeneity. Similarly, there was no association of M-stage with OS in patients with prior LT (M1-stage: 1.04 [0.81-1.33]; unknown: 0.98 [0.79-1.21]) or without prior LT (M1-stage: 0.95 [0.70-1.29]; unknown: 1.17 [0.80-1.71]) with no significant heterogeneity. Based on M-stage at presentation, we did not find any significant heterogeneity in treatment effect on rPFS (interaction p = 0.13), and OS (interaction p = 0.87).

CONCLUSION

M-stage at presentation had no association with survival in chemotherapy-naïve mCRPC. We did not find any statistically significant heterogeneity in efficacy of dual ARAT based on synchronous versus metachronous presentation.

Cardiovascular Complications in Patients with Prostate Cancer: Potential Molecular Connections

Cardiovascular diseases (CVDs) and complications are often seen in patients with prostate cancer (PCa) and affect their clinical management. Despite acceptable safety profiles and patient compliance, androgen deprivation therapy (ADT), the mainstay of PCa treatment and chemotherapy, has increased cardiovascular risks and metabolic syndromes in patients. A growing body of evidence also suggests that patients with pre-existing cardiovascular conditions show an increased incidence of PCa and present with fatal forms of the disease. Therefore, it is possible that a molecular link exists between the two diseases, which has not yet been unraveled. This article provides insight into the connection between PCa and CVDs. In this context, we present our findings linking PCa progression with patients' cardiovascular health by performing a comprehensive gene expression study, gene set enrichment (GSEA) and biological pathway analysis using publicly available data extracted from patients with advanced metastatic PCa. We also discuss the common androgen deprivation strategies and CVDs most frequently reported in PCa patients and present evidence from various clinical trials that suggest that therapy induces CVD in PCa patients.

Neoadjuvant Androgen Receptor Signaling Inhibitors before Radical Prostatectomy for Non-Metastatic Advanced Prostate Cancer: A Systematic Review

(1) Background: Several phase II studies, including randomized controlled trials (RCTs), assessed the efficacy of adding androgen receptor signaling inhibitors (ARSIs) to androgen deprivation therapy (ADT) as a neoadjuvant treatment in patients treated with radical prostatectomy (RP) for prostate cancer (PCa). Summarizing the early results of these studies could help in designing phase III trials and patient counseling. (2) Methods: We queried three databases in January 2023 for studies that included PCa patients treated with neoadjuvant ARSI-based combination therapy before RP. The outcomes of interest were oncologic outcomes and pathologic responses, such as pathologic complete response (pCR) and minimal residual disease (MRD). (3) Results: Overall, twenty studies (eight RCTs) were included in this systematic review. Compared to ADT or ARSI alone, ARSI + ADT was associated with higher pCR and MRD rates; this effect was less evident when adding a second ARSI or chemotherapy. Nevertheless, ARSI + ADT resulted in relatively low pCR rates (0-13%) with a high proportion of ypT3 (48-90%) in the resected specimen. PTEN loss, ERG positive, or intraductal carcinoma seem to be associated with worse pathologic response. One study that adjusted for the effects of possible confounders reported that neoadjuvant ARSI + ADT improved time to biochemical recurrence and metastasis-free survival compared to RP alone. (4) Conclusions: Neoadjuvant ARSI + ADT combination therapy results in improved pathologic response compared to either alone or none in patients with non-metastatic advanced PCa. Ongoing phase III RCTs with long-term oncologic outcomes, as well as biomarker-guided studies, will clarify the indication, oncologic benefits, and adverse events of ARSI + ADT in patients with clinically and biologically aggressive PCa.

Circulating tumor cell quantification during abiraterone plus prednisone therapy may estimate survival in metastatic castration-resistant prostate cancer patients

PURPOSE

Circulating tumor cells (CTCs) predict survival in response to different interventions in metastatic castration-resistant prostate cancer (mCRPC) patients. This study aimed to explore the dynamic change in CTCs during abiraterone plus prednisone therapy and its optimal threshold for prognostication in mCRPC patients.

METHODS

CTCs in blood samples from mCRPC patients (N = 98) at baseline and in the 2nd month after abiraterone plus prednisone treatment initiation (M2) were enumerated by using the CellSearch System.

RESULTS

CTCs were detected in 64.8% of mCRPC patients at baseline with a median value (interquartile range) of 2.0 (0.0-4.0). Elevated CTC count was related to visceral metastasis (P = 0.003), high alkaline phosphatase (P = 0.043), and high lactate dehydrogenase (P = 0.007). Baseline CTC ≥ 1 (vs. < 1) was only associated with shortened radiographic progression-free survival (rPFS) (P = 0.043); additionally, baseline CTC ≥ 5 (vs. < 5) was linked with unfavorable rPFS (P = 0.037) and overall survival (OS) (P = 0.021). Following the therapy, CTCs were reduced at M2 (P < 0.001). Notably, CTC ≥ 1 (vs. < 1) (P = 0.002) and CTC ≥ 5 (vs. < 5) (P < 0.001) at M2 were related to shortened rPFS according to the Kaplan‒Meier curves, and they could independently estimate deteriorative rPFS in the multivariate Cox regression (P = 0.043 and P = 0.027, respectively). Similarly, CTC ≥ 1 (vs. < 1) (P = 0.022) and CTC ≥ 5 (vs. < 5) (P = 0.002) at M2 were related to shortened OS, whereas only CTC ≥ 5 (vs. < 5) could independently predict unfavorable OS (P = 0.017).

CONCLUSION

CTC count ≥ 5 at M2 exhibits excellent prognostic value for abiraterone plus prednisone therapy in mCRPC patients.

NIR-triggerable self-assembly multifunctional nanocarriers to enhance the tumor penetration and photothermal therapy efficiency for castration-resistant prostate cancer

Great challenges still remain in the management of patients with castration-resistant prostate cancer (CRPC) based on traditional treatments, and the rapid development of nanotechnology may find a breakthrough. Herein, a novel type of multifunctional self-assembly magnetic nanocarriers (IR780-MNCs) containing iron oxide nanoparticles (Fe₃O₄ NPs) and IR780 iodide was synthesized by an optimized process. With a hydrodynamic diameter of 122 nm, a surface charge of -28.5 mV and the drug loading efficiency of 89.6%, IR780-MNCs have increased cellular uptake efficiency, long-term stability, ideal photothermal conversion ability and excellent superparamagnetic behavior. The in vitro study indicated that IR780-MNCs have excellent biocompatibility and could induce significant cell apoptosis under the 808 nm laser irradiation. The in vivo study showed that IR780-MNCs highly accumulated at the tumor area could reduce the tumor volume of tumor-bearing mice by 88.5% under the 808 nm laser irradiation, but minimal damage to surrounding normal tissues. Since IR780-MNCs encapsulated a large number of 10 nm homogeneous spherical Fe₃O₄ NPs, which can be used as T₂ contrast agent, the best window for photothermal therapy can be determined through MRI. In conclusion, IR780-MNCs have initially showed excellent antitumor effect and biosafety in the treatment of CRPC. This work provides novel insights into the precise treatment of CRPC by using a safe nanoplatform based on the multifunctional nanocarriers.

Association between age and efficacy of combination systemic therapies in patients with metastatic hormone-sensitive prostate cancer: a systematic review and meta-analysis

BACKGROUND

Combination systemic therapies have become the standard for metastatic hormone-sensitive prostate cancer (mHSPC). However, the effect of age on oncologic outcomes remains unknown. Our aim was to perform a systematic review, meta-analysis, and network meta-analysis (NMA) on the effect of chronological age on overall survival (OS) in patients treated with combination therapies for mHSPC.

METHODS

We searched the PubMed®, Web of ScienceTM, and Scopus® databases to identify randomized controlled trials (RCTs) that analyzed the efficacy of combination systemic therapies using ADT plus docetaxel and/or androgen receptor signaling inhibitor (ARSI) in patients with mHSPC. We included studies, which provided separate hazard ratios (HRs) for younger vs. older patients. The selected age cut-off was 70 years (±5 years). Our outcome of interest was OS.

RESULTS

We included nine RCTs with a total of 9183 patients. Younger and older men constituted 51% and 49% of included patients, respectively. Docetaxel plus ADT significantly improved OS among both older (HR 0.79, 95% CI 0.63-0.99, p = 0.04) and younger patients (HR 0.79, 95% CI 0.69-0.90, p < 0.001) with no differences according to age. ARSI plus ADT improved OS in older (HR 0.72, 95% CI 0.64-0.80, p < 0.001) and younger (HR 0.58, 95% CI 0.51-0.66, p < 0.001) patients; younger patients did benefit more (p = 0.02). On NMA treatment ranking, triplet therapy showed the highest probability of OS benefit irrespective of age group; in older patients, the benefit of triplet therapy compared to doublet was less expressed.

CONCLUSIONS

Patients with mHSPC benefit from combination systemic therapies irrespective of age; the effect is, however, more evident in younger patients. Chronological age alone seems not to be a selection criteria for the administration of combination systemic therapies.

Potential role for protein kinase D inhibitors in prostate cancer

Protein kinase D (PrKD), a novel serine-threonine kinase, belongs to a family of calcium calmodulin kinases that consists of three isoforms: PrKD1, PrKD2, and PrKD3. The PrKD isoforms play a major role in pathologic processes such as cardiac hypertrophy and cancer progression. The charter member of the family, PrKD1, is the most extensively studied isoform. PrKD play a dual role as both a proto-oncogene and a tumor suppressor depending on the cellular context. The duplicity of PrKD can be highlighted in advanced prostate cancer (PCa) where expression of PrKD1 is suppressed whereas the expressions of PrKD2 and PrKD3 are upregulated to aid in cancer progression. As understanding of the PrKD signaling pathways has been better elucidated, interest has been garnered in the development of PrKD inhibitors. The broad-spectrum kinase inhibitor staurosporine acts as a potent PrKD inhibitor and is the most well-known; however, several other novel and more specific PrKD inhibitors have been developed over the last two decades. While there is tremendous potential for PrKD inhibitors to be used in a clinical setting, none has progressed beyond preclinical trials due to a variety of challenges. In this review, we focus on PrKD signaling in PCa and the potential role of PrKD inhibitors therein, and explore the possible clinical outcomes based on known function and expression of PrKD isoforms at different stages of PCa.

Androgen Receptor Signaling Inhibition in Advanced Castration Resistance Prostate Cancer: What Is Expected for the Near Future?

The androgen signaling pathway is the cornerstone in the treatment of high risk or advanced prostate cancer patients. However, in recent years, different mechanisms of resistance have been defined in this field, limiting the efficacy of the currently approved antiandrogen drugs. Different therapeutic approaches are under research to assess the role of combination therapies against escape signaling pathways or the development of novel antiandrogen drugs to try to solve the primary or acquired resistance against androgen dependent or independent pathways. The present review aims to summarize the current state of androgen inhibition in the therapeutic algorithm of patients with advanced prostate cancer and the mechanisms of resistance to those available drugs. In addition, this review conducted a comprehensive overview of the main present and future research approaches in the field of androgen receptor inhibition to overcome these resistances and the potential new drugs under research coming into this setting.

Evaluation of the role of local therapy in patients with cN1M0 prostate cancer: A population-based study from the SEER database

Objective

To investigate the prognostic value of local therapy (LT) in cN1M0 prostate cancer (PCa).

Methods

Patients diagnosed with cN1M0 PCa were extracted from the surveillance, epidemiology, and end results (SEER) database. Kaplan-Meier (KM) curve was used to compare the survival outcomes between patients treated with and without LT. Further, among patients receiving LT, KM analysis was also applied to investigate the survival differences in patients with radical prostatectomy (RP) and radiation therapy (RT). Propensity score matching (PSM) analysis was performed to balance the basic characteristics of patients in each group and make it comparable when exploring the survival impact of different treatment types. Finally, uni- and multivariable Cox proportional-hazards models were utilized to identify independent prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS) in this population.

Results

Patients treated with LT had significantly better OS (P<0.0001) and CSS (P<0.0001) than those without LT, as well as in most subgroups, except for non-White patients, or those with ISUP grade group 1 or T3 stage. Notably, patients receiving RP also had significantly better OS (P=0.00012) and CSS (P=0.0045) than those treated with RT alone, especially in those aged ≥75 years old, prostate-specific antigen (PSA) 10-20 ng/mL, ISUP grade 1-3 or non-white patients. Finally, clinical T stage, ISUP grade group and the administration of LT were identified to be independent prognostic factors for OS and CSS among cN1M0 PCa patients.

Conclusion

The cN1M0 PCa patients treated with LT were associated with significantly better survival. Among patients receiving LT, the combination of RP and PLND could lead to a better prognosis compared to RT alone in most subgroups. An individualized treatment strategy is warranted to be developed after weighing the benefits and risks of treatment.

Metastatic castrate-resistant prostate cancer: a new horizon beyond the androgen receptors

PURPOSE OF REVIEW

Systemic chemotherapy and second-generation androgen receptor-axis targeted therapies have been in the forefront of management for metastatic castrate-resistant prostate cancer (mCRPC) patients with low or high symptom burden. However, in the recent past, due to improvement in molecular characterization, management of mCRPC has witnessed long strides of advancement. We aim to review the novel nonhormonal and nonchemotherapeutic treatment options.

RECENT FINDINGS

Poly (ADP-ribose) polymerase inhibitors (PARPis) such as olaparib and rucaparib have been recently approved by the US FDA for use in mCRPC with germline or somatic mutations in homologous recombination repair. The combination of PARPi with androgen receptor axis-targeted agents (ARAT) or dual ARAT-based therapy has shown superior radiographic progression-free survival as a first-line treatment. A combination of AKT inhibitor ipatasertib and abiraterone has shown improvement in radiographic progression-free survival as a first-line treatment. Prostate-specific membrane antigen (PSMA)-targeted radiopharmaceutical like 177Lu-PSMA-617, a beta particle emitter has demonstrated improvement in overall survival in mCRPC patients pretreated with ARAT or taxanes. Although immune checkpoint inhibitors are being tested in mCRPC, there is no robust evidence to support this premise.

SUMMARY

These new agents have widened the treatment options for mCRPC patients. Overall treatment should be focused on improving survival while limiting the deterrent effect on the quality of life.

Venous Thromboembolism in Cancer Patients Undergoing Chemotherapy: A Systematic Review and Meta-Analysis

Objective: Venous thromboembolism (VTE) is a life-threatening complication that may exacerbate cancer prognosis. Whilst some studies indicate an increased risk of VTE in cancer patients undergoing chemotherapy, the prevalence estimates on the pooled prevalence of VTE in cancer patients undergoing chemotherapy are not known. This study aims to calculate the pooled prevalence of VTE in chemotherapy-treated cancer patients. Methods: Studies on VTE occurrence in cancer patients undergoing chemotherapy were retrieved after database search. The terms used included “cancer”, “chemotherapy”, and “venous thromboembolism”. A random-effects meta-analysis was conducted to obtain a pooled estimate of VTE prevalence in cancer patients undergoing chemotherapy. Results: A total of 102 eligible studies involving 30,671 patients (1773 with VTE, 28,898 without) were included in the meta-analysis. The pooled estimate of VTE prevalence was found to be 6%, ranging from 6% to 7% (ES 6%; 95% CI 6−7%; z = 18.53; p < 0.001). Conclusions: The estimated pooled prevalence rate of VTEs was 6% in cancer patients undergoing CRT, which was higher than the overall crude prevalence rate (5.78%). Comprehensive cancer care should consider stratified VTE risk assessment based on cancer phenotype, given that certain phenotypes of cancer such as bladder, gastric and ovarian posing particularly high risks of VTE.

Deep learning identifies explainable reasoning paths of mechanism of action for drug repurposing from multilayer biological network

The discovery and repurposing of drugs require a deep understanding of the mechanism of drug action (MODA). Existing computational methods mainly model MODA with the protein-protein interaction (PPI) network. However, the molecular interactions of drugs in the human body are far beyond PPIs. Additionally, the lack of interpretability of these models hinders their practicability. We propose an interpretable deep learning-based path-reasoning framework (iDPath) for drug discovery and repurposing by capturing MODA on by far the most comprehensive multilayer biological network consisting of the complex high-dimensional molecular interactions between genes, proteins and chemicals. Experiments show that iDPath outperforms state-of-the-art machine learning methods on a general drug repurposing task. Further investigations demonstrate that iDPath can identify explicit critical paths that are consistent with clinical evidence. To demonstrate the practical value of iDPath, we apply it to the identification of potential drugs for treating prostate cancer and hypertension. Results show that iDPath can discover new FDA-approved drugs. This research provides a novel interpretable artificial intelligence perspective on drug discovery.

Emerging Role of PARP Inhibitors in Metastatic Prostate Cancer

PURPOSE OF REVIEW

We highlight the clinical development of Poly (ADP-Ribose) polymerase (PARP) inhibitors in prostate cancer.

RECENT FINDINGS

Approximately 10 to 30% of metastatic prostate cancer patients carry germline or somatic mutations in DNA repair pathways. BRCA2 is the most commonly mutated gene in DNA damage repair pathways. Because of its critical function in homologous recombination repair (HRR) machinery, deleterious BRCA2 mutation enables synthetic lethality to a PARP inhibitor. Olaparib demonstrated clinical benefit in patients with deleterious mutations in HRR-related genes and most clearly in patients with BRCA2 mutations. Olaparib received the US FDA approval or mCRPC patients with a qualifying HRR gene mutation in May 2020. Rucaparib received an accelerated FDA approval for patients with BRCA1- or BRCA2-mutated mCRPC based on 43% objective response rate in a phase II study. To expand the application of a PARP inhibitor, several trials have evaluated various combination strategies with an androgen receptor signaling inhibitor, immunotherapy, radium-223, and others. While no PARP inhibitor combination regimen has been approved, promising data from a PARP inhibitor and an ASI combination have been reported. PARP inhibitor represents a standard treatment for patient with mCRPC with germline or somatic mutations in BRCA2 and other HRR pathway genes.

Systemic triplet therapy for metastatic hormone-sensitive prostate cancer: A systematic review and network meta-analysis

Purpose: To perform a systematic review and network meta-analysis to compare the efficacy and safety of currently available docetaxel-based systemic triplet therapies for metastatic hormone-sensitive prostate cancer (mHSPC).

Methods: We searched for eligible publications in PubMed, Embase, and Cochrane CENTRAL. Improvements in overall survival (OS) and radiographic progression-free time (rPFS) were compared indirectly using network meta-analysis and evaluated using the surface under the cumulative ranking curve (SUCRA). Other secondary endpoints, such as time to castration-resistant prostate cancer and/or adverse events (AEs), were also compared and evaluated.

Results: Five trials were selected and analyzed using a network meta-analysis. Compared to androgen deprivation therapy (ADT) plus docetaxel, darolutamide (hazard ratio [HR]: 0.68, 95% credible interval [CrI]: 0.57–0.80) and abiraterone (HR: 0.75, 95% CrI: 0.59–0.95) triplet therapy had significantly longer OS, and darolutamide triplet therapy was the first treatment ranked. Abiraterone (HR: 0.49, 95% CrI: 0.39–0.61) and enzalutamide (HR: 0.52, 95% CrI: 0.30–0.89) had significantly better rPFS than ADT plus docetaxel; however, all three therapies, including abiraterone, apalutamide, and enzalutamide, were the best options with a similar SUCRA. At most secondary endpoints, systemic triplet therapy was superior to ADT plus docetaxel. The risk of any AEs in darolutamide or abiraterone triplet therapy was comparable with ADT plus docetaxel (odds ratio [OR]: 2.53, 95% credible interval [CrI]: 0.68–12.63; OR: 1.07, 95% CrI: 0.03–36.25). Abiraterone triplet therapy had an increased risk of grade≥3 AEs (OR: 1.56, 95% CrI: 1.15–2.11).

Conclusion: Systemic triplet therapy was more effective than ADT plus docetaxel for mHSPC. Of the triplet therapy regimens, darolutamide ranked first in terms of improved OS. Abiraterone and enzalutamide triplet ranked first in terms of rFPS, however, it did not confer a statistically difference among all triplet regimens. The overall risk of AEs was comparable. More studies are required for current and potential combinations of systemic triplet therapy.

Androgen Annihilation Versus Advanced Androgen Blockage as First Line Treatment for Metastatic Castration Resistant Prostate Cancer: a systematic review and meta-analysis

BACKGROUND

Despite recent advances in the treatments of metastatic castration resistant prostate cancer (mCRPC), patients' prognosis remains suboptimal and novel treatment combinations are under scrutiny. On this matter, the recent ACIS trial tested the role of abiraterone plus apalutamide (androgen annihilation) in addition to androgen deprivation therapy, versus abiraterone plus androgen deprivation therapy. Herein, we performed a meta-analysis to compare overall survival (OS) and progression free survival (PFS) among patients who received androgen annihilation versus advanced androgen blockage (abiraterone or enzalutamide), in addition to conventional androgen deprivation therapy.

METHODS

A comprehensive search for all published phase III randomized control trials on first line mCRPC that evaluated advanced androgen blockage (COU-AA-302, PREVAIL) or androgen annihilation (ACIS) was conducted PubMed, EMBASE, Web of Science, and Scopus databases up to 31/12/2021. We reconstructed survival data from published Kaplan-Meier curves on overall survival (OS) and progression free survival (PFS) and meta-analyzed androgen annihilation versus advanced androgen blockage (grouping together abiraterone and enzalutamide) versus androgen deprivation therapy. The outcomes of interest were assessed using difference in restricted mean survival time (ΔRMST) at different time points.

RESULTS

Three trials were included involving 3787 patients. Overall, patients receiving androgen annihilation exhibited similar OS compared to advanced androgen blockage: ΔRMST at 36 months of -0.2 (95%CI: -1.1, 0.8, p=0.8). At 36 months, relatively to ADT alone, patients receiving androgen annihilation or advanced androgen blockage exhibited longer OS: ΔRMST of 1.6 (95%CI: 0.6, 2.7, p=0.002) and 1.8 months (95%CI: 1.1, 2.5, p<0.001), respectively. Patients receiving androgen annihilation exhibited better PFS compared to advanced androgen blockage: ΔRMST at 36 months of 2.4 months (95%CI: 1.0, 3.8, p=0.001).

CONCLUSION

We found no OS benefit for patients with mCRPC treated with androgen annihilation compared to advanced androgen blockage. This might be ascribed to an increased rate of other cause mortality that might determine the absence of an OS benefit or to the efficacy of second line therapies. Optimal treatment sequence and patient selection for androgen annihilation remain open points. However, a PFS benefit was found in case of combination therapy, whose clinical meaning is not yet clear.

Assessing the correlation between second progression-free survival (PFS2) and overall survival (OS) in advanced prostate cancer patients using medical data vision (MDV) claims database in Japan

OBJECTIVE

To assess the correlation between PFS2 and OS among patients with advanced prostate cancer (PC) in a real-world setting for Japan.

METHODS

This was a retrospective analysis using the Japanese MDV database. Patients with nmCRPC (non-metastatic Castration-Resistant PC), mCRPC (metastatic Castration-Resistant PC), and mCNPC (metastatic Castration-Naïve PC) were identified and their medical records were investigated for PFS2 and death. Association between PFS2 and OS was determined using the Pearson's, Spearman's, Kendall's Tau, and Fleischers' correlation coefficients.

RESULTS

A total of 386,484 patients with PC were identified from the database, of which, 1,783 patients with nmCRPC, 630 with mCRPC, and 454 with mCNPC met the predefined eligibility criteria. Significant correlation between PFS2 and OS was observed in patients with nmCRPC (Pearson's r = 0.873; 95% CI: 0.849-0.897, Spearman's r = 0.909; 95% CI: 0.893-0.925; Kendall's Tau r = 0.831; 95% CI: 0.812-0.850, Fleischers' r = 0.682; 95% CI: 0.601-0.764), mCRPC (Pearson's r = 0.812; 95% CI: 0.758-0.865, Spearman's r = 0.895; 95% CI: 0.868-0.923, Kendall's Tau r = 0.789; 95% CI: 0.755-0.823, Fleischers' r= 0.439; 95% CI: 0.334-0.544), and mCNPC (Pearson's r = 0.931; 95% CI: 0.899-0.964, Spearman's r = 0.943; 95% CI: 0.922-0.964, Kendall's Tau r = 0.866; 95% CI: 0.836-0.896, Fleischers' r = 0.756; 95% CI: 0.624-0.888).

CONCLUSIONS

The results of this study indicate a significant correlation between PFS2 and OS, which adds additional evidence to the existing literature of using PFS2 as a surrogate endpoint for OS in patients with PC.

Metronomic Chemotherapy in Prostate Cancer

Despite the significant expansion of the therapeutic armamentarium associated with the introduction of novel endocrine therapies, cytotoxic agents, radiopharmaceuticals, and PARP inhibitors, progression of metastatic castration-resistant prostate cancer (mCRPC) beyond treatment options remains the leading cause of death in advanced prostate cancer patients. Metronomic chemotherapy (MC) is an old concept of wise utilization of cytotoxic agents administered continuously and at low doses. The metronomic is unique due to its multidimensional mechanisms of action involving: (i) inhibition of cancer cell proliferation, (ii) inhibition of angiogenesis, (iii) mitigation of tumor-related immunosuppression, (iv) impairment of cancer stem cell functions, and (v) modulation of tumor and host microbiome. MC has been extensively studied in advanced prostate cancer before the advent of novel therapies, and its actual activity in contemporary, heavily pretreated mCRPC patients is unknown. We have conducted a prospective analysis of consecutive cases of mCRPC patients who failed all available standard therapies to find the optimal MC regimen for phase II studies. The metronomic combination of weekly paclitaxel 60 mg/m² i.v. with capecitabine 1500 mg/d p.o. and cyclophosphamide 50 mg/d p.o. was selected as the preferred regimen for a planned phase II study in heavily pretreated mCRPC patients.

Recent advances in the treatment of advanced prostate cancer: maximizing existing therapies while searching for novel solutions

PURPOSE OF REVIEW

Present highlights from recent research examining treatment of advanced prostate cancer.

RECENT FINDINGS

Data are emerging that combining androgen deprivation, docetaxel, and additional androgen-receptor-targeted therapies in treatment naïve metastatic prostate cancer may be an effective strategy to improve outcomes. Genomically targeted therapies and radiopharmaceuticals continue to be evaluated in the treatment of advanced castration-resistant prostate cancer.

SUMMARY

Although no clear consensus has emerged regarding the best sequencing of available therapeutics, trial results continue to support moving available therapies earlier in the disease course. Data continue to build for novel radiopharmaceuticals soon to likely be approved for treatment of castration-resistant disease.

Review of second-generation androgen receptor inhibitor therapies and their role in prostate cancer management

PURPOSE OF REVIEW

We review the published literature on the indications of second-generation androgen receptor inhibitors, Poly(ADP-Ribose) Polymerase (PARP) inhibitors, combination therapies, and their evolution throughout the advanced prostate cancer continuum.

RECENT FINDINGS

Enzalutamide trials have published data supporting its use in metastatic hormone-sensitive prostate cancer (mHSPC), nonmetastatic castration-resistant prostate cancer (nmCRPC), and metastatic castration-resistant prostate cancer (mCRPC). Apalutamide trials have supported its indication for mHSPC and nmCRPC. Darolutamide trials currently support its use for nmCRPC. Abiraterone trials have supported its use in mCRPC and mHSPC. Olaparib and rucaparib have shown clinical benefit in heavily pretreated patients with mCRPC and DNA repair mutation genes.

SUMMARY

Phase 3 trials and peer-reviewed literature demonstrate that enzalutamide, apalutamide, and darolutamide prolong overall survival (OS) in men with nmCRPC. Abiraterone, enzalutamide, and apalutamide improve OS in men with mHSPC. Abiraterone and enzalutamide have data supporting improvement in OS in men with mCRPC.

Comparison of Systemic Treatments for Metastatic Castration-Resistant Prostate Cancer After Docetaxel Failure: A Systematic Review and Network Meta-analysis

Background: Lacking head-to-head trial, the optimal treatment for patients with metastatic castration-resistant prostate cancer (mCRPC) after docetaxel failure is unclear. This study is to compare the efficacy and safety of systemic treatments in patients who progressed after docetaxel to aid clinical decision-making.

Methods: Databases including MEDLINE, EMBASE, and the Cochrane Library were searched from inception to June 15th, 2021. The outcomes of interest include overall survival (OS), biochemical progression-free survival (bPFS), and serious adverse events (SAEs). The Cochrane risk of bias tools were used to assess study quality. Indirect comparisons of competing treatments were performed via Bayesian network meta-analysis.

Results: Five trials with 3,862 patients comparing four treatments (abiraterone, enzalutamide, cabazitaxel, and radium-223) were identified. All the four treatments were associated with improved OS and bPFS relative to best supportive care. Among them, enzalutamide (hazard ratio [HR] = 0.58, 95% credible interval [Crl]: 0.49–0.69) had the highest probability of ranking first in terms of OS, followed by cabazitaxel (HR = 0.70, 95% Crl: 0.59–0.83), radium-223 (HR = 0.71, 95% Crl: 0.56–0.90) and abiraterone (HR = 0.73, 95% Crl: 0.63–0.84). Similarly, enzalutamide (HR = 0.25, 95% Crl: 0.20–0.31) showed the greatest improvement of bPFS, followed by abiraterone (HR = 0.60, 95% Crl: 0.51–0.71) and cabazitaxel (HR = 0.75, 95% Crl: 0.63–0.89). In terms of safety, treatments ranked from the safest to the least safe were radium-223 (OR = 0.58, 95% Crl: 0.20–1.68), enzalutamide (OR = 0.80, 95% Crl: 0.28–2.29), abiraterone (OR = 0.94, 95% Crl: 0.39–2.27) and cabazitaxel (OR = 2.50, 95% Crl: 0.84–7.44).

Conclusion: For patients with mCRPC who progressed after docetaxel, enzalutamide may offer the most significant survival benefits and satisfying safety. Cabazitaxel is effective in post-docetaxel settings but associated with a high risk of SAEs. Although network meta-analysis provides indirect comparisons and ranking probabilities, the results should be treated with caution as it cannot replace randomized direct comparison.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020223040, identifier CRD42020223040.

Abiraterone acetate and prednisolone with or without enzalutamide for high-risk non-metastatic prostate cancer: a meta-analysis of primary results from two randomised controlled phase 3 trials of the STAMPEDE platform protocol

BACKGROUND

Men with high-risk non-metastatic prostate cancer are treated with androgen-deprivation therapy (ADT) for 3 years, often combined with radiotherapy. We analysed new data from two randomised controlled phase 3 trials done in a multiarm, multistage platform protocol to assess the efficacy of adding abiraterone and prednisolone alone or with enzalutamide to ADT in this patient population.

METHODS

These open-label, phase 3 trials were done at 113 sites in the UK and Switzerland. Eligible patients (no age restrictions) had high-risk (defined as node positive or, if node negative, having at least two of the following: tumour stage T3 or T4, Gleason sum score of 8-10, and prostate-specific antigen [PSA] concentration ≥40 ng/mL) or relapsing with high-risk features (≤12 months of total ADT with an interval of ≥12 months without treatment and PSA concentration ≥4 ng/mL with a doubling time of <6 months, or a PSA concentration ≥20 ng/mL, or nodal relapse) non-metastatic prostate cancer, and a WHO performance status of 0-2. Local radiotherapy (as per local guidelines, 74 Gy in 37 fractions to the prostate and seminal vesicles or the equivalent using hypofractionated schedules) was mandated for node negative and encouraged for node positive disease. In both trials, patients were randomly assigned (1:1), by use of a computerised algorithm, to ADT alone (control group), which could include surgery and luteinising-hormone-releasing hormone agonists and antagonists, or with oral abiraterone acetate (1000 mg daily) and oral prednisolone (5 mg daily; combination-therapy group). In the second trial with no overlapping controls, the combination-therapy group also received enzalutamide (160 mg daily orally). ADT was given for 3 years and combination therapy for 2 years, except if local radiotherapy was omitted when treatment could be delivered until progression. In this primary analysis, we used meta-analysis methods to pool events from both trials. The primary endpoint of this meta-analysis was metastasis-free survival. Secondary endpoints were overall survival, prostate cancer-specific survival, biochemical failure-free survival, progression-free survival, and toxicity and adverse events. For 90% power and a one-sided type 1 error rate set to 1·25% to detect a target hazard ratio for improvement in metastasis-free survival of 0·75, approximately 315 metastasis-free survival events in the control groups was required. Efficacy was assessed in the intention-to-treat population and safety according to the treatment started within randomised allocation. STAMPEDE is registered with ClinicalTrials.gov, NCT00268476, and with the ISRCTN registry, ISRCTN78818544.

FINDINGS

Between Nov 15, 2011, and March 31, 2016, 1974 patients were randomly assigned to treatment. The first trial allocated 455 to the control group and 459 to combination therapy, and the second trial, which included enzalutamide, allocated 533 to the control group and 527 to combination therapy. Median age across all groups was 68 years (IQR 63-73) and median PSA 34 ng/ml (14·7-47); 774 (39%) of 1974 patients were node positive, and 1684 (85%) were planned to receive radiotherapy. With median follow-up of 72 months (60-84), there were 180 metastasis-free survival events in the combination-therapy groups and 306 in the control groups. Metastasis-free survival was significantly longer in the combination-therapy groups (median not reached, IQR not evaluable [NE]-NE) than in the control groups (not reached, 97-NE; hazard ratio [HR] 0·53, 95% CI 0·44-0·64, p<0·0001). 6-year metastasis-free survival was 82% (95% CI 79-85) in the combination-therapy group and 69% (66-72) in the control group. There was no evidence of a difference in metatasis-free survival when enzalutamide and abiraterone acetate were administered concurrently compared with abiraterone acetate alone (interaction HR 1·02, 0·70-1·50, p=0·91) and no evidence of between-trial heterogeneity (I2 p=0·90). Overall survival (median not reached [IQR NE-NE] in the combination-therapy groups vs not reached [103-NE] in the control groups; HR 0·60, 95% CI 0·48-0·73, p<0·0001), prostate cancer-specific survival (not reached [NE-NE] vs not reached [NE-NE]; 0·49, 0·37-0·65, p<0·0001), biochemical failure-free-survival (not reached [NE-NE] vs 86 months [83-NE]; 0·39, 0·33-0·47, p<0·0001), and progression-free-survival (not reached [NE-NE] vs not reached [103-NE]; 0·44, 0·36-0·54, p<0·0001) were also significantly longer in the combination-therapy groups than in the control groups. Adverse events grade 3 or higher during the first 24 months were, respectively, reported in 169 (37%) of 451 patients and 130 (29%) of 455 patients in the combination-therapy and control groups of the abiraterone trial, respectively, and 298 (58%) of 513 patients and 172 (32%) of 533 patients of the combination-therapy and control groups of the abiraterone and enzalutamide trial, respectively. The two most common events more frequent in the combination-therapy groups were hypertension (abiraterone trial: 23 (5%) in the combination-therapy group and six (1%) in control group; abiraterone and enzalutamide trial: 73 (14%) and eight (2%), respectively) and alanine transaminitis (abiraterone trial: 25 (6%) in the combination-therapy group and one (<1%) in control group; abiraterone and enzalutamide trial: 69 (13%) and four (1%), respectively). Seven grade 5 adverse events were reported: none in the control groups, three in the abiraterone acetate and prednisolone group (one event each of rectal adenocarcinoma, pulmonary haemorrhage, and a respiratory disorder), and four in the abiraterone acetate and prednisolone with enzalutamide group (two events each of septic shock and sudden death).

INTERPRETATION

Among men with high-risk non-metastatic prostate cancer, combination therapy is associated with significantly higher rates of metastasis-free survival compared with ADT alone. Abiraterone acetate with prednisolone should be considered a new standard treatment for this population.

FUNDING

Cancer Research UK, UK Medical Research Council, Swiss Group for Clinical Cancer Research, Janssen, and Astellas.

Sequencing of Systemic Therapies in the Management of Advanced Prostate Cancer in India: a Delphi-Based Consensus

INTRODUCTION

With the availability of an increasing number of therapeutic options for advanced prostate cancer (APC), optimal sequencing and combination of therapies have emerged to be the areas of challenges. In the Indian context, there is a dearth of consensus recommendations to guide clinicians regarding optimal sequencing of therapy in APC management. A Delphi-based consensus regarding optimal therapy sequencing in APC management was developed by an expert panel of medical oncologists from across India.

METHODS

An expert scientific committee of 11 medical oncologists and an expert panel of 53 medical oncologists from India constituted the panel for the Delphi consensus. In the first phase, a questionnaire with 41 clinical statements was developed in several critical controversial areas in APC treatment. In the second phase, 29 clinical statements were reworked and sent to eight experts to obtain their opinions on best practices. The consensus ratings were based on a 9-point Likert scale. Based on the overall response, statements with a mean score of ≥ 7 with 1 outlier were considered as "consensus."

RESULTS

Degarelix was the preferred androgen deprivation therapy (ADT). While ADT plus docetaxel was the preferred option for metastatic castrate-sensitive/naïve prostate cancer patients with high-volume disease, ADT with abiraterone was the preferred choice for low-volume disease. Docetaxel was the preferred first-line treatment option in men who received ADT alone in the castrate-sensitive/naïve setting. For patients progressing on or after docetaxel for metastatic castrate-resistant prostate cancer (without prior abiraterone or enzalutamide), the experts reached a consensus on the use of enzalutamide as the preferred second-line treatment option. No consensus was reached for the third-line treatment options.

CONCLUSION

This article is intended to serve as a guide to help clinicians discuss with their patients as part of the shared and multidisciplinary decision-making for improved APC management in India.

SPOP-mutant prostate cancer: Translating fundamental biology into patient care

Comprehensive cancer genome studies have revealed genetically-defined subtypes of prostate cancer with distinct truncal driver mutations. Because prostate cancer has been largely seen as a rather uniform disease, the clinical significance of this discovery remained largely obscure. However, recent findings imply distinct biological features and therapeutic vulnerabilities linked to specific truncal mutations. Here we review our current understanding of prostate cancers harboring recurrent point mutations in the ubiquitin ligase adaptor protein SPOP and discuss opportunities for future clinical translation. More specifically, activation of the androgen receptor (AR) signaling emerges as the key oncogenic pathway. SPOP-mutant prostate cancer patients respond to AR inhibition in various clinical settings. Molecular insights on how mutant SPOP promotes tumorigenesis may open more specific therapeutic avenues which, in combination with conventional AR-targeting agents, could improve the outcome of patients with SPOP-mutant prostate cancer.