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

Prognostic model for second progression-free survival and overall survival in patients with high-risk metastatic hormone-sensitive prostate cancer treated with abiraterone acetate and androgen deprivation therapy

BACKGROUND

To develop and validate a prognostic risk model for high-risk metastatic hormone-sensitive prostate cancer (mHSPC) patients treated with upfront abiraterone acetate (ABI).

METHODS

This retrospective multicenter study involved 233 high-risk mHSPC patients who received upfront ABI, developed by three academic centers. The model was externally validated with an independent cohort of 282 patients. To identify independent prognostic factors for second progression-free survival (PFS2) and develop the best-fitted model, Cox proportional hazards regression, followed by the Akaike information criterion, was used. Patients were categorized into three groups based on their risk scores. PFS2 and overall survival (OS) were evaluated according to the risk groups in the discovery and validation cohorts.

RESULTS

The median age was 72 (range 51-89) years, with a median follow-up duration of 27 months. Independent factors linked to PFS2 included an Eastern Cooperative Oncology Group performance status ≥2, a primary Gleason score of 5, an extent of disease score of ≥3 or liver metastasis, and lactate dehydrogenase >220 U/L. Median PFS2 for favorable-, intermediate-, and poor-risk groups were not reached, 43 months, and 16 months, respectively. The median OS was 29 months in the poor-risk group, whereas it was not reached in the favorable- and intermediate-risk groups. The 2-year OS rates in the favorable-, intermediate- and poor-risk groups were 94.5%, 80.1%, and 60.3%, respectively. The validation cohort confirmed the risk model's relationship with PFS2 and OS. The median PFS2 and OS in the high-risk group were 21 months and 32 months, respectively.

CONCLUSIONS

Our prognostic model, including five clinical factors, is useful for patient care and treatment selection in high-risk mHSPC patients treated with ADT plus ABI. The developed model could provide more accurate information, guide treatment decisions, or classify patients in future clinical trials.

Nanomedicines in diagnosis and treatment of prostate cancers: an updated review

Prostate cancer (PC) is the third most common male cancer in the world, which occurs due to various mutations leading to the loss of chromatin structure. There are multiple treatments for this type of cancer, of which chemotherapy is one of the most important. Sometimes, a combination of different treatments, such as chemotherapy, radiotherapy, and surgery, are used to prevent tumor recurrence. Among other treatments, androgen deprivation therapy (ADT) can be mentioned, which has had promising results. One of the drawbacks of chemotherapy and ADT treatments is that they are not targeted to the tumor tissue. For this reason, their use can cause extensive side effects. Treatments based on nanomaterials, known as nanomedicine, have attracted much attention today. Nanoparticles (NPs) are one of the main branches of nanomedicine, and they can be made of different materials such as polymer, metal, and carbon, each of which has distinct characteristics. In addition to NPs, nanovesicles (NVs) also have therapeutic applications in PC. In treating PC, synthetic NVs (liposomes, micelles, and nanobubbles) or produced from cells (exosomes) can be used. In addition to the role that NPs and NVs have in treating PC, due to being targeted, they can be used to diagnose PC and check the treatment process. Knowing the characteristics of nanomedicine-based treatments can help design new treatments and improve researchers' understanding of tumor biology and its rapid diagnosis. In this study, we will discuss conventional and nanomedicine-based treatments. The results of these studies show that the use of NPs and NVs in combination with conventional treatments has higher efficacy in tumor treatment than the individual use of each of them.

Androgen receptor pathway inhibitors and taxanes in metastatic prostate cancer: an outcome-adaptive randomized platform trial

ProBio is the first outcome-adaptive platform trial in prostate cancer utilizing a Bayesian framework to evaluate efficacy within predefined biomarker signatures across systemic treatments. Prospective circulating tumor DNA and germline DNA analysis was performed in patients with metastatic castration-resistant prostate cancer before randomization to androgen receptor pathway inhibitors (ARPIs), taxanes or a physician's choice control arm. The primary endpoint was the time to no longer clinically benefitting (NLCB). Secondary endpoints included overall survival and (serious) adverse events. Upon reaching the time to NLCB, patients could be re-randomized. The primary endpoint was met after 218 randomizations. ARPIs demonstrated ~50% longer time to NLCB compared to taxanes (median, 11.1 versus 6.9 months) and the physician's choice arm (median, 11.1 versus 7.4 months) in the biomarker-unselected or 'all' patient population. ARPIs demonstrated longer overall survival (median, 38.7 versus 21.7 and 21.8 months for taxanes and physician's choice, respectively). Biomarker signature findings suggest that the largest increase in time to NLCB was observed in AR (single-nucleotide variant/genomic structural rearrangement)-negative and TP53 wild-type patients and TMPRSS2-ERG fusion-positive patients, whereas no difference between ARPIs and taxanes was observed in TP53-altered patients. In summary, ARPIs outperform taxanes and physician's choice treatment in patients with metastatic castration-resistant prostate cancer with detectable circulating tumor DNA. ClinicalTrials.gov registration: NCT03903835 .

Japanese clinical practice guidelines for prostate cancer 2023

This fourth edition of the Japanese Clinical Practice Guidelines for Prostate Cancer 2023 is compiled. It was revised under the leadership of the Japanese Urological Association, with members selected from multiple academic societies and related organizations (Japan Radiological Society, Japanese Society for Radiation Oncology, the Department of EBM and guidelines, Japan Council for Quality Health Care (Minds), Japanese Society of Pathology, and the patient group (NPO Prostate Cancer Patients Association)), in accordance with the Minds Manual for Guideline Development (2020 ver. 3.0). The most important feature of this revision is the adoption of systematic reviews (SRs) in determining recommendations for 14 clinical questions (CQs). Qualitative SRs for these questions were conducted, and the final recommendations were made based on the results through the votes of 24 members of the guideline development group. Five algorithms based on these results were also created. Contents not covered by the SRs, which are considered textbook material, have been described in the general statement. In the general statement, a literature search for 14 areas was conducted; then, based on the general statement and CQs of the Japanese Clinical Practice Guidelines for Prostate Cancer 2016, the findings revealed after the 2016 guidelines were mainly described. This article provides an overview of these guidelines.

Comparison of Short-Term Outcomes and Safety Profiles between Androgen Deprivation Therapy+Abiraterone/Prednisone and Androgen Deprivation Therapy+Docetaxel in Patients with De Novo Metastatic Hormone-Sensitive Prostate Cancer

PURPOSE

This study aimed to compare the short-term outcomes and safety profiles of androgen-deprivation therapy (ADT)+abiraterone/prednisone with those of ADT+docetaxel in patients with de novo metastatic hormone-sensitive prostate cancer (mHSPC).

MATERIALS AND METHODS

A web-based database system was established to collect prospective cohort data for patients with mHSPC in Korea. From May 2019 to November 2022, 928 patients with mHSPC from 15 institutions were enrolled. Among these patients, data from 122 patients who received ADT+abiraterone/prednisone or ADT+docetaxel as the primary systemic treatment for mHSPC were collected. The patients were divided into two groups: ADT+abiraterone/prednisone group (n=102) and ADT+docetaxel group (n=20). We compared the demographic characteristics, medical histories, baseline cancer status, initial laboratory tests, metastatic burden, oncological outcomes for mHSPC, progression after mHSPC treatment, adverse effects, follow-up, and survival data between the two groups.

RESULTS

No significant differences in the demographic characteristics, medical histories, metastatic burden, and baseline cancer status were observed between the two groups. The ADT+abiraterone/prednisone group had a lower prostate-specific antigen (PSA) progression rate (7.8% vs. 30.0%; p=0.011) and lower systemic treatment discontinuation rate (22.5% vs. 45.0%; p=0.037). No significant differences in adverse effects, oncological outcomes, and total follow-up period were observed between the two groups.

CONCLUSIONS

ADT+abiraterone/prednisone had lower PSA progression and systemic treatment discontinuation rates than ADT+docetaxel. In conclusion, further studies involving larger, double-blinded randomized trials with extended follow-up periods are necessary.

Metastatic Hormone-Sensitive Prostate Cancer and Combination Treatment Outcomes: A Review

Importance

Metastatic hormone-sensitive prostate cancer is currently an incurable disease. Despite a high response rate to androgen-deprivation therapy, most cases progress to castration-resistant disease, the terminal phase. This review provides a summary of the most recent evidence for current and emerging management strategies, including treatment intensification with combinations of therapies. It also provides recommendations on applying the evidence in clinical practice to encourage appropriate treatment to improve survival outcomes among patients with metastatic hormone-sensitive prostate cancer.

Observations

Androgen-deprivation therapy is the backbone of treatment for metastatic hormone-sensitive prostate cancer; however, it is insufficient alone to provide sustained disease control and long-term survival. Addition of an androgen receptor pathway inhibitor and/or docetaxel significantly improves survival, as demonstrated by several international phase 3 randomized clinical trials. Triplet therapy composed of androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel has been shown to improve overall survival over androgen-deprivation therapy plus docetaxel. In the ARASENS trial (darolutamide), the hazard ratios (HRs) were 0.68 (95% CI, 0.57-0.80) in the overall population; 0.71 (95% CI, 0.59-0.85) and 0.61 (95% CI, 0.35-1.05) in patients with de novo and recurrent disease, respectively; 0.69 (95% CI, 0.57-0.82) and 0.72 (95% CI, 0.41-1.13) in patients with high-volume and low-volume disease, respectively; and 0.71 (95% CI, 0.58-0.86) and 0.62 (95% CI, 0.42-0.90) in patients with high-risk and low-risk disease, respectively. In the PEACE-1 trial (abiraterone acetate + prednisone), the HRs were 0.75 (95% CI, 0.59-0.95; all de novo) in the overall population and 0.72 (95% CI, 0.55-0.95) and immature in the high-volume and low-volume subgroups, respectively. In the ENZAMET trial (enzalutamide), the HRs were 0.82 (95% CI, 0.63-1.06) in the overall population; 0.73 (95% CI, 0.55-0.99) and 1.10 (95% CI, 0.65-1.86) in the de novo and recurrent subgroups, respectively; and 0.87 (95% CI, 0.66-1.17) and 0.61 (95% CI, 0.33-1.10) in the high-volume and low-volume subgroups. Combination regimens are generally well tolerated, with adverse effects dependent on the profiles of the component drugs.

Conclusions and relevance

The findings of this review show compelling evidence from phase 3 randomized clinical trials in favor of initiating triplet combination therapy for patients with metastatic hormone-sensitive prostate cancer for the best overall survival. Patients who are eligible for chemotherapy should be offered androgen-deprivation therapy plus an androgen receptor pathway inhibitor plus docetaxel, particularly patients with high-volume, high-risk, or de novo metastatic disease.

Health-related quality of life in patients with metastatic hormone-sensitive prostate cancer treated with androgen receptor signaling inhibitors: the role of combination treatment therapy

BACKGROUND

While the addition of androgen receptor signaling inhibitors (ARSIs) to androgen deprivation therapy (ADT) results in better of overall survival in patients with metastatic hormone-sensitive prostate cancer (mHSPC), information regarding health related quality of life (HR-QoL) is sparse. We aimed at summarizing current evidence on the impact of ARSIs on HR-QoL.

METHODS

We performed a systematic review of the published literature on PubMed/EMBASE, Web of Science, SCOPUS, and the Cochrane libraries between January 2011 and April 2022. We included only phase III randomized controlled trials (RCT), which were selected according to the PRISMA guidelines. We aimed at evaluating differences in HR-QoL, assessed by validated patient reported outcomes instruments. We analyzed global scores and sub-domains such as sexual functioning, urinary symptoms, bowel symptoms, pain/fatigue, emotional and social/family wellbeing. We reported data descriptively.

RESULTS

Six RCTs were included: two used enzalutamide with ADT as intervention arms (ARCHES, ENZAMET); one used apalutamide with ADT (TITAN); two abiraterone acetate and prednisone (AAP) with ADT (STAMPEDE, LATITUDE); and one darolutamide with ADT (ARASENS). Enzalutamide or AAP with ADT increase overall HR-QoL in comparison with ADT alone, ADT with first generation nonsteroideal anti-androgens or ADT with docetaxel, whereas apalutamide and darolutamide with ADT maintain HR-QoL similarly to ADT alone or ADT with docetaxel, respectively. Time to first deterioration of pain was longer with combination therapy with enzalutamide, AAP or darolutamide, but not with apalutamide. No worsening of emotional wellbeing was reported from the addition of ARSIs to ADT than ADT alone.

CONCLUSIONS

The addition of ARSIs to ADT in mHSPC tends to increase overall HR-QoL and prolong time to first deterioration of pain/fatigue compared with ADT alone, ADT with first generation nonsteroideal anti-androgens, and ADT with docetaxel. ARSIs show a complex interaction with remaining HR-QoL domains. We advocate a standardization of HR-QoL measurement and reporting to allow further comparisons.

Radiographic Progression-Free Survival and Clinical Progression-Free Survival as Potential Surrogates for Overall Survival in Men With Metastatic Hormone-Sensitive Prostate Cancer

PURPOSE

Despite major increases in the longevity of men with metastatic hormone-sensitive prostate cancer (mHSPC), most men still die of prostate cancer. Phase III trials assessing new therapies in mHSPC with overall survival (OS) as the primary end point will take approximately a decade to complete. We investigated whether radiographic progression-free survival (rPFS) and clinical PFS (cPFS) are valid surrogates for OS in men with mHSPC and could potentially be used to expedite future phase III clinical trials.

METHODS

We obtained individual patient data (IPD) from 9 eligible randomized trials comparing treatment regimens (different androgen deprivation therapy [ADT] strategies or ADT plus docetaxel in the control or research arms) in mHSPC. rPFS was defined as the time from random assignment to radiographic progression or death from any cause whichever occurred first; cPFS was defined as the time from random assignment to the date of radiographic progression, symptoms, initiation of new treatment, or death, whichever occurred first. We implemented a two-stage meta-analytic validation model where conditions of patient-level and trial-level surrogacy had to be met. We then computed the surrogate threshold effect (STE).

RESULTS

IPD from 6,390 patients randomly assigned from 1994 to 2012 from 13 units were pooled for a stratified analysis. The median OS, rPFS, and cPFS were 4.3 (95% CI, 4.2 to 4.5), 2.4 (95% CI, 2.3 to 2.5), and 2.3 years (95% CI, 2.2 to 2.4), respectively. The STEs were 0.80 and 0.81 for rPFS and cPFS end points, respectively.

CONCLUSION

Both rPFS and cPFS appear to be promising surrogate end points for OS. The STE of 0.80 or higher makes it viable for either rPFS or cPFS to be used as the primary end point that is surrogate for OS in phase III mHSPC trials with testosterone suppression alone as the backbone therapy and would expedite trial conduct.

Metastatic Hormone-Sensitive Prostate Cancer in the Era of Doublet and Triplet Therapy

OPINION STATEMENT

Treatment for metastatic hormone-sensitive prostate cancer has undergone significant evolution in recent years, leading to substantial improvements in overall survival. Men are living longer than ever before with a median survival now which is almost 6 years. The timing and extent of metastatic disease combined with individual patient factors helps treatment recommendation of doublet therapy including androgen deprivation (ADT) plus either chemotherapy or androgen receptor signaling inhibition (ARSI) or triplet therapy with ADT+ARSI+chemotherapy. New treatments must continue to be developed to enhance survival with goals of cure. Better biomarkers that allow for more effective treatments will enhance disease control, quality of life, and survival.

Does Research from Clinical Trials in Metastatic Hormone-sensitive Prostate Cancer Treatment Translate into Access to Treatments for Patients in the "Real World"? A Systematic Review

CONTEXT

Since 2015 there have been major advances in the management of primary metastatic hormone-sensitive prostate cancer (mHSPC) following the publication of key clinical trials that demonstrated significant clinical benefits with docetaxel chemotherapy or novel hormone therapy (NHT) in addition to androgen deprivation therapy (ADT). Despite these advances, there is evidence to show that these treatments are not being utilised for mHSPC in clinical practice.

OBJECTIVE

To determine the utilisation of docetaxel and NHT in mHSPC in routine practice and the determinants of variation in their use.

EVIDENCE ACQUISITION

MEDLINE and Embase were searched systematically for studies on utilisation of treatments for primary mHSPC that were based on regional or national data sets and published after January 2005. Study results were summarised using a narrative synthesis.

EVIDENCE SYNTHESIS

Thirteen papers were included in the analysis, six full-text articles and seven abstracts, on studies that included a total of 166 876 patients. The utilisation rate of treatment intensification with either docetaxel or NHT (enzalutamide, apalutamide, or abiraterone) in addition to ADT ranged from 9.3% to 38.1% across the studies. Younger, White patients with fewer comorbidities and living in more urban settings were more likely to be prescribed treatment intensification. Patients treated in private academic institutions by oncologists were more likely to receive docetaxel or NHT. Socioeconomic status did not impact receipt of systemic therapy. NHT utilisation rates appear to have increased over time.

CONCLUSIONS

These results highlight the need to change the approach to the treatment of primary mHSPC in the real world by harnessing the practice-changing results from recent trials in this setting to optimise upfront systemic therapy for this patient population.

PATIENT SUMMARY

We reviewed the use of treatments for primary metastatic hormone-sensitive prostate cancer that showed a benefit in key clinical trials. We found that these treatments are underused, particularly among certain patient groups.

A territory-wide real-world efficacy and toxicity analysis of abiraterone acetate versus docetaxel in 574 Asian patients with metastatic hormone-sensitive prostate cancer

INTRODUCTION

Abiraterone acetate (ABI) or docetaxel (DOC), in addition to androgen-deprivation therapy (ADT), are current treatment options for metastatic hormone-sensitive prostate cancer (mHSPC). No randomized head-to-head trial has compared these 2 mHSPC treatments, and real-world data regarding their outcomes in Asian patients are lacking.

PATIENTS AND METHODS

The medical records of mHSPC patients who began upfront ABI or DOC treatment in addition to ADT at seven public oncology centers in Hong Kong between 2015 and 2021 were reviewed. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), prostate-specific antigen (PSA) response, and toxicities. Kaplan-Meier and multivariate Cox regression analyses were performed.

RESULTS

A total of 574 patients were included, of whom 419 received DOC and 155 received ABI. The median follow-up duration was 22.4 (DOC group: 23.8; ABI group: 17.3) months. The ABI group demonstrated significantly better PFS than the DOC group (not reached vs. 15.1 months: hazard ratio = 0.37; 95% confidence interval = 0.28-0.50; P < .001). No significant OS difference was observed (P = .58). Failure to achieve a ≥ 90% decline in PSA level at 3 months and failure to achieve an undetectable PSA nadir were each associated with unfavorable PFS and OS. Patients who received DOC had a higher rate of febrile neutropenia, whereas those who received ABI had higher rates of grade ≥ 3 hypokalemia and elevated alanine transaminase. Treatment discontinuation due to toxicities was more common in the DOC (3.6%) than the ABI (0.6%) group.

CONCLUSION

In Asian mHSPC patients, upfront ABI + ADT was associated with better PFS than DOC + ADT, with no significant OS difference. PSA kinetics may help stratify the prognosis for treatment intensification. Toxicity profiles were different, with a higher rate of toxicity-related treatment discontinuation in the DOC group.

LncRNA BRCAT54 is downregulated and inhibits cancer cell proliferation by downregulating miR-130b-3p through methylation in prostate cancer

BRCAT54 and miR-130b-3p are two recently characterized critical players in cancer biology, while their functions in prostate cancer (PC) are unknown. From preliminary sequencing analysis, we observed altered expression of BRCAT54 and miR-130b-3p in PC and an inverse correlation between them. This study was conducted to explore their involvement in PC. A total of 64 PC patients were enrolled to collect paired PC and nontumor tissues. The expression of BRCAT54 and miR-130b-3p were determined by RT-qPCR. Overexpression of BRCAT54 and miR-130b-3p was achieved in PC cells to explore their roles in regulating the expression of each other. Methylation-specific PCR (MSP) was conducted to explore the role of BRCAT54 in regulating promoter methylation of miR-130b-3p. BrdU assay was used to evaluate the role of BRCAT54 and miR-130b-3p in regulating PC cell proliferation. The results showed that PC tissues exhibited downregulation of BRCAT54 and upreglation of miR-130b-3p compared to that in nontumor tissues. They were inversely correlated across PC tissue samples. Overexpression of BRCAT54 decreased RNA accumulation of miR-130b-3p in PC cells. In addition, overexpression of BRCAT54 increased promoter methylation of miR-130b-3p. Moreover, BRCAT54 suppressed the role of miR-130b-3p in promoting PC cell proliferation. In conclusion, BRCAT54 is downregulated in PC and it may inhibit cancer cell proliferation by downregulating miR-130b-3p through methylation.

Ki67 and prostate specific antigen are prognostic in metastatic hormone naïve prostate cancer

BACKGROUND

For metastatic hormone naïve prostate cancer patients, androgen deprivation therapy (ADT) with escalation therapy including docetaxel and/or androgen targeting drugs is the standard therapy. However, de-escalation is preferable to avoid unnecessary side effects, especially from docetaxel, but markers to identify these patients are lacking. The purpose of the present study was to investigate the potential of PSA and Ki67 immunoreactive scores as prognostic and treatment-predictive markers.

MATERIAL AND METHODS

Prostate biopsies from 92 patients with metastatic hormone naïve PC (PSA > 80 ng/mL or clinical metastases) were immunohistochemically evaluated for PSA and Ki67. Gene expression analysis was performed with Clariom D microarrays to identify the phenotypic profile associated with the immunohistochemistry scores of biopsies. Cox regression analysis for progression free survival after ADT adjustment for age, ISUP, and serum PSA and Kaplan-Meier analyses were performed to assess prognostic values of Ki67, PSA, and the Ki67/PSA ratio.

RESULTS

The immunohistochemical score for PSA was the strongest prognostic factor for progression-free and overall survival after ADT. Consequently, the ratio between Ki67 and PSA displayed a stronger prognostic value than Ki67 itself. Further, mRNA expression data analysis showed an association between high Ki67/PSA ratio, cell-cycle regulation, and DNA damage repair. In an exploratory sub-analysis of 12 patients treated with early docetaxel as addition to ADT and matched controls, a high Ki67/PSA ratio showed potential to identify those who benefit from docetaxel.

CONCLUSION

PSA and Ki67 immunoreactive scores are prognostic in the metastatic hormone-sensitive setting, with PSA being superior. The combination of Ki67 and PSA did not give additional prognostic value. The results suggest immunohistochemical scoring of PSA to have potential to improve identification of patients responding well to ADT alone.

Suppression of Tumor Cell Lactate-generating Signaling Pathways Eradicates Murine PTEN/p53-deficient Aggressive-variant Prostate Cancer via Macrophage Phagocytosis

PURPOSE

Phosphatase and tensin homolog (PTEN) loss-of-function/PI3K pathway hyperactivation is associated with poor therapeutic outcomes and immune checkpoint inhibitor resistance across multiple malignancies. Our prior studies in Pb-Cre;PTENfl/flTrp53fl/fl genetically engineered mice (GEM) with aggressive-variant prostate cancer (AVPC) demonstrated tumor growth control in 60% mice following androgen deprivation therapy/PI3K inhibitor (PI3Ki)/programmed cell death protein 1 (PD-1) antibody combination, via abrogating lactate cross-talk between cancer cells and tumor-associated macrophages (TAM), and suppression of histone lactylation (H3K18lac)/phagocytic activation within TAM. Here, we targeted immunometabolic mechanism(s) of PI3Ki resistance, with the goal of durable tumor control in AVPC.

EXPERIMENTAL DESIGN

Pb-Cre;PTENfl/flTrp53fl/fl GEM were treated with PI3Ki (copanlisib), MEK inhibitor (trametinib) or Porcupine inhibitor (LGK'974) singly or their combinations. MRI was used to monitor tumor kinetics and immune/proteomic profiling/ex vivo coculture mechanistic studies were performed on GEM tumors or corresponding tumor-derived cell lines.

RESULTS

Given our proteomic profiling showing persistent MEK signaling within tumors of PI3Ki-resistant GEM, we tested whether addition of trametinib to copanlisib enhances tumor control in GEM, and we observed 80% overall response rate via additive suppression of lactate within TME and H3K18lac within TAM, relative to copanlisib (37.5%) monotherapy. The 20% resistant mice demonstrated feedback Wnt/β-catenin activation, resulting in restoration of lactate secretion by tumor cells and H3K18lac within TAM. Cotargeting Wnt/β-catenin signaling with LGK'974 in combination with PI3Ki/MEKi, demonstrated durable tumor control in 100% mice via H3K18lac suppression and complete TAM activation.

CONCLUSIONS

Abrogation of lactate-mediated cross-talk between cancer cells and TAM results in durable ADT-independent tumor control in PTEN/p53-deficient AVPC, and warrants further investigation in clinical trials.

The STAMPEDE2 Trial: a Site Survey of Current Patterns of Care, Access to Imaging and Treatment of Metastatic Prostate Cancer

AIMS

The forthcoming STAMPEDE2 trial has three comparisons in metastatic hormone-sensitive prostate cancer. We aim to determine clinical practices among STAMPEDE trial investigators for access to imaging and therapeutic choices and explore their interest in participation in STAMPEDE2.

MATERIALS AND METHODS

The survey was developed and distributed online to 120 UK STAMPEDE trial sites. Recipients were invited to complete the survey between 16 and 30 May 2022. The survey consisted of 30 questions in five sections on access to stereotactic ablative body radiotherapy (SABR), 177lutetium-prostate-specific membrane antigen-617 (177Lu-PSMA-617), choice of systemic therapies and use of positron emission tomography/computerised tomography and whole-body magnetic resonance imaging.

RESULTS

From 58/120 (48%) sites, 64 respondents completed the survey: 55/64 (86%) respondents were interested to participate in SABR, 44/64 (69%) in 177Lu-PSMA-617 and 56/64 (87.5%) in niraparib with abiraterone comparisons; 45/64 (70%) respondents had access to bone, spine and lymph node metastases SABR delivery and 7/64 (11%) to 177Lu-PSMA-617. In addition to androgen deprivation therapy, 60/64 (94%) respondents used androgen receptor signalling inhibitors and 46/64 (72%) used docetaxel; 29/64 (45%) respondents would consider triplet therapy with androgen deprivation therapy, androgen receptor signalling inhibitors and docetaxel. Positron emission tomography/computerised tomography was available to 62/64 (97%) respondents and requested by 45/64 (70%) respondents for disease uncertainty on conventional imaging and 39/64 (61%) at disease relapse. Whole-body magnetic resonance imaging was available to 24/64 (38%) respondents and requested by 13/64 (20%) respondents in highly selected patients. In low-volume disease, 38/64 (59%) respondents requested scans at baseline and disease relapse. In high-volume disease, 29/64 (45%) respondents requested scans at baseline, best response (at prostate-specific antigen nadir) and disease relapse; 54/64 (84%) respondents requested computerised tomography and bone scan for best response assessment.

CONCLUSION

There is noteworthy disparity in clinical practice across current study sites, however most have expressed an interest in participation in the forthcoming STAMPEDE2 trial.

Local Therapeutics for the Treatment of Oligo Metastatic Prostate Cancer

PURPOSE OF REVIEW

Metastatic prostate cancer remains universally lethal. Although de-novo metastatic prostate cancer was historically managed with systemic therapy alone, local therapies are increasingly utilized in the early treatment of the disease, particularly in patients with oligometastatic prostate cancer (OMPC). OMPC represents an intermediate stage between clinically localized and widespread metastatic disease. Diseases classified within this stage present an opportunity for localized targeting of the disease prior to progression to widespread metastases. The purpose of this review is to discuss the contemporary and emerging local therapies for the treatment of OMPC.

RECENT FINDINGS

To date, there are three utilized forms of local therapy for OMPC: cryoablation, radiation therapy, and cytoreductive prostatectomy. Cryoablation can be utilized for the total ablation of the prostate and has shown promising results in patients with OMPC either in combination with ADT or with ADT and systemic chemotherapy. Radiation therapy along with ADT has demonstrated improvement in progression-free survival. The STAMPEDE Arm G, PEACE-1, and the HORRAD clinical trials have investigated radiation therapy for mPCa compared to standard of care versus systemic therapy with varying results. Cytoreductive radical prostatectomy (CRP) in conjunction with ADT has also been proposed in the management of OPMC with promising results from case-control and retrospective studies. Currently there are larger controlled trials investigating CRP for OPMC including the SIMCAP, LoMP, TRoMbone, SWOG 1802, IP2-ATLANTA, g-RAMPP, and FUSCC-OMPCa trials. Given the novel nature of local treatments for OPMC, treatment selection is still controversial and requires long-term follow-up and randomized clinical trials to aid patient and clinician decision making.

DIONYSIUS trial: "Does increasing oxygen nurture your symptomatic ischaemic ulcer sufficiently?" Study protocol for an international multicentre randomised trial

INTRODUCTION

Diabetic foot ulcers (DFUs) are a major complication of diabetes and often associated with peripheral arterial occlusive disease. Current available evidence shows hyperbaric oxygen therapy (HBOT) can reduce the risk of major amputation, but clinicians remain sceptical about the (cost-)effectiveness and feasibility of HBOT for ischaemic DFUs in clinical practice. Therefore, vascular surgeons and HBOT physicians worldwide feel a strong need for a sufficiently powered clinical trial to determine whether and how many HBOT sessions may be a (cost-)effective adjunctive treatment to ischaemic DFUs.

METHODS

An international, multicentre, multi-arm multi-stage design is chosen to conduct an efficient randomised clinical trial. Patients will be randomised to receive standard care (wound treatment and surgical interventions following international guidelines) with either 0, 20, 30 or at least 40 sessions of HBOT. These sessions will comprise 90-120 min of HBOT at a pressure of 2.2-2.5 atmospheres absolute according to international standards. Based on a planned interim analysis, the best performing study arm(s) will continue. Primary end point is major amputation (ie, above ankle) rate after 12 months. Secondary end points are amputation-free survival, wound healing, health-related quality of life and cost-effectiveness.

ETHICS AND DISSEMINATION

All patients enrolled in this trial will receive maximum vascular, endovascular or conservative treatment and local wound care according to best practice and (inter)national guidelines. HBOT therapy is added to the standard treatment and is regarded as a low-risk to moderate-risk therapy. The study is approved by the medical ethics committee of the Amsterdam University Medical Centers, location University of Amsterdam.

TRIAL REGISTRATION NUMBER

2020-000449-15, NL9152, NCT05804097.

Suppression of tumor cell lactate-generating signaling pathways eradicates murine PTEN/p53-deficient aggressive-variant prostate cancer via macrophage phagocytosis

Purpose

PTEN loss-of-function/PI3K pathway hyperactivation occurs in ∼50% of metastatic, castrate-resistant prostate cancer patients, resulting in poor therapeutic outcomes and resistance to immune checkpoint inhibitors across multiple malignancies. Our prior studies in prostate-specific PTEN/p53-deleted genetically engineered mice (Pb-Cre;PTEN fl/fl Trp53 fl/fl GEM) with aggressive-variant prostate cancer (AVPC) demonstrated feedback Wnt/β-catenin signaling activation in 40% mice resistant to androgen deprivation therapy (ADT)/PI3K inhibitor (PI3Ki)/PD-1 antibody (aPD-1) combination, resulting in restoration of lactate cross-talk between tumor-cells and tumor-associated macrophages (TAM), histone lactylation (H3K18lac) and phagocytic suppression within TAM. Here, we targeted immunometabolic mechanism(s) of resistance to ADT/PI3Ki/aPD-1 combination, with the goal of durable tumor control in PTEN/p53-deficient PC.

Experimental design

Pb-Cre;PTEN fl/fl Trp53 fl/fl GEM were treated with either ADT (degarelix), PI3Ki (copanlisib), aPD-1, MEK inhibitor (trametinib) or Porcupine inhibitor (LGK 974) as single agents or their combinations. MRI was used to monitor tumor kinetics and immune/proteomic profiling/ ex vivo co-culture mechanistic studies were performed on prostate tumors or established GEM-derived cell lines.

Results

We tested whether Wnt/β-catenin pathway inhibition with LGK 974 addition to degarelix/copanlisib/aPD-1 therapy enhances tumor control in GEM, and observed de novo resistance due to feedback activation of MEK signaling. Based on our observation that degarelix/aPD-1 treatment resulted in partial inhibition of MEK signaling, we substituted trametinib for degarelix/aPD-1 treatment, and observed a durable tumor growth control of PI3Ki/MEKi/PORCNi in 100% mice via H3K18lac suppression and complete TAM activation within TME.

Conclusions

Abrogation of lactate-mediated cross-talk between cancer cells and TAM results in durable ADT-independent tumor control in PTEN/p53-deficient AVPC, and warrants further investigation in clinical trials.

STATEMENT OF TRANSLATIONAL RELEVANCE

PTEN loss-of-function occurs in ∼50% of mCRPC patients, and associated with poor prognosis, and immune checkpoint inhibitor resistance across multiple malignancies. Our prior studies have demonstrated that ADT/PI3Ki/PD-1 triplet combination therapy controls PTEN/p53-deficient PC in 60% of mice via enhancement of TAM phagocytosis. Here, we discovered that resistance to ADT/PI3K/PD-1 therapy occurred via restoration of lactate production via feedback Wnt/MEK signaling following treatment with PI3Ki, resulting in inhibition of TAM phagocytosis. Critically, co-targeting of PI3K/MEK/Wnt signaling pathways using an intermittent dosing schedule of corresponding targeted agents resulted in complete tumor control and significantly prolonged survival without significant long-term toxicity. Collectively, our findings provide "proof-of-concept" that targeting lactate as a macrophage phagocytic checkpoint controls growth of murine PTEN/p53-deficient PC and warrant further investigation in AVPC clinical trials.

Reversal of Lactate and PD-1-mediated Macrophage Immunosuppression Controls Growth of PTEN/p53-deficient Prostate Cancer

PURPOSE

Phosphatase and tensin homolog (PTEN) loss of function occurs in approximately 50% of patients with metastatic castrate-resistant prostate cancer (mCRPC), and is associated with poor prognosis and responsiveness to standard-of-care therapies and immune checkpoint inhibitors. While PTEN loss of function hyperactivates PI3K signaling, combinatorial PI3K/AKT pathway and androgen deprivation therapy (ADT) has demonstrated limited anticancer efficacy in clinical trials. Here, we aimed to elucidate mechanism(s) of resistance to ADT/PI3K-AKT axis blockade, and to develop rational combinatorial strategies to effectively treat this molecular subset of mCRPC.

EXPERIMENTAL DESIGN

Prostate-specific PTEN/p53-deficient genetically engineered mice (GEM) with established 150-200 mm3 tumors, as assessed by ultrasound, were treated with either ADT (degarelix), PI3K inhibitor (copanlisib), or anti-PD-1 antibody (aPD-1), as single agents or their combinations, and tumors were monitored by MRI and harvested for immune, transcriptomic, and proteomic profiling, or ex vivo co-culture studies. Single-cell RNA sequencing on human mCRPC samples was performed using 10X Genomics platform.

RESULTS

Coclinical trials in PTEN/p53-deficient GEM revealed that recruitment of PD-1-expressing tumor-associated macrophages (TAM) thwarts ADT/PI3Ki combination-induced tumor control. The addition of aPD-1 to ADT/PI3Ki combination led to TAM-dependent approximately 3-fold increase in anticancer responses. Mechanistically, decreased lactate production from PI3Ki-treated tumor cells suppressed histone lactylation within TAM, resulting in their anticancer phagocytic activation, which was augmented by ADT/aPD-1 treatment and abrogated by feedback activation of Wnt/β-catenin pathway. Single-cell RNA-sequencing analysis in mCRPC patient biopsy samples revealed a direct correlation between high glycolytic activity and TAM phagocytosis suppression.

CONCLUSIONS

Immunometabolic strategies that reverse lactate and PD-1-mediated TAM immunosuppression, in combination with ADT, warrant further investigation in patients with PTEN-deficient mCRPC.

Defining Patient Benefits from High-intensity Intermittent Therapy for Hormone-sensitive Prostate Cancer

Intensification of systemic therapy beyond androgen deprivation therapy (ADT) with the addition of novel androgen receptor pathway inhibitors (ARPIs) is associated with better overall survival (OS) in comparison to ADT alone in metastatic hormone-sensitive prostate cancer (mHSPC). However, continuous use of ARPIs, as is currently standard in routine practice, may be associated with long-term toxicities, lower quality of life (QOL), and higher health care costs. Post hoc analyses of contemporary ARPI trials suggest that the depth of the initial prostate-specific antigen (PSA) response is associated with favorable long-term outcomes. While a prior large randomized trial (S9346) failed to demonstrate noninferiority of intermittent ADT in patients with HSPC, evaluation of high-intensity intermittent therapy is warranted. This involves a strategy whereby more potent systemic therapy is interrupted by treatment breaks in selected patients with mHSPC as a means to improve QOL and reduce costs, while not impacting cancer-related outcomes. PATIENT SUMMARY: Intensified hormonal treatment is a standard of care in advanced prostate cancer. Treatment breaks may be beneficial in patients with an outstanding response to therapy. Further trials are warranted to identify which subgroups of patients may benefit from this approach.

First-line Systemic Treatment Options for Metastatic Castration-Sensitive Prostate Cancer: A Living Systematic Review and Network Meta-analysis

Importance

The effectiveness of triplet therapy compared with androgen pathway inhibitor (API) doublets in a heterogeneous patient population with metastatic castration-sensitive prostate cancer (mCSPC) is unknown.

Objective

To assess the comparative effectiveness of contemporary systemic treatment options for patients with mCSPC across clinically relevant subgroups.

Data Sources

For this systematic review and meta-analysis, Ovid MEDLINE and Embase were searched from each database's inception (MEDLINE, 1946; Embase, 1974) through June 16, 2021. Subsequently, a "living" auto search was created with weekly updates to identify new evidence as it became available.

Study Selection

Phase 3 randomized clinical trials (RCTs) assessing first-line treatment options for mCSPC.

Data Extraction and Synthesis

Two independent reviewers extracted data from eligible RCTs. The comparative effectiveness of different treatment options was assessed with a fixed-effect network meta-analysis. Data were analyzed on July 10, 2022.

Main Outcomes and Measures

Outcomes of interest included overall survival (OS), progression-free survival (PFS), grade 3 or higher adverse events, and health-related quality of life.

Results

This report included 10 RCTs with 11 043 patients and 9 unique treatment groups. Median ages of the included population ranged from 63 to 70 years. Current evidence for the overall population suggests that the darolutamide (DARO) triplet (DARO + docetaxel [D] + androgen deprivation therapy [ADT]; hazard ratio [HR], 0.68; 95% CI, 0.57-0.81), as well as the abiraterone (AAP) triplet (AAP + D + ADT; HR, 0.75; 95% CI, 0.59-0.95), are associated with improved OS compared with D doublet (D + ADT) but not compared with API doublets. Among patients with high-volume disease, AAP + D + ADT may improve OS compared with D + ADT (HR, 0.72; 95% CI, 0.55-0.95) but not compared with AAP + ADT, enzalutamide (E) + ADT, and apalutamide (APA) + ADT. For patients with low-volume disease, AAP + D + ADT may not improve OS compared with APA + ADT, AAP + ADT, E + ADT, and D + ADT.

Conclusions and Relevance

The potential benefit observed with triplet therapy must be interpreted with careful accounting for the volume of disease and the choice of doublet comparisons used in the clinical trials. These findings suggest an equipoise to how triplet regimens compare with API doublet combinations and provide direction for future clinical trials.

Docetaxel versus abiraterone for metastatic hormone-sensitive prostate cancer with focus on efficacy of sequential therapy

PURPOSE

We aimed to assess the oncologic efficacy of combining docetaxel (DOC) versus abiraterone (ABI) with androgen deprivation therapy (ADT) in patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC), with a focus on the efficacy of sequential therapy, in a real-world clinical practice setting.

METHODS

The records of 336 patients who harbored de novo high-risk mHSPC, based on the LATITUDE criteria, and had received ADT with either DOC (n = 109) or ABI (n = 227) were retrospectively analyzed. Overall survival (OS), cancer-specific survival (CSS), progression-free survival (PFS), including time to castration-resistant prostate cancer (CRPC), time to 2nd-line progression (PFS2), and 2nd- and 3rd-line PFS, were compared. We used one-to-two propensity score matching to minimize the confounders. The differential efficacy of 2nd-line therapy based on agents in each arm was evaluated using the unmatched cohort as an additional interest.

RESULTS

After propensity score matching, 86 patients treated with DOC + ADT and 172 with ABI + ADT were available for analyses. The 3-year OS and CSS for DOC versus ABI were 76.2% versus 75.1% (p = 0.8) and 78.2% versus 78.6% (p = 1), respectively. There was no difference in the median PFS2 (49 vs. 43 months, p = 0.39), while the median time to CRPC in patients treated with ABI was significantly longer compared to those treated with DOC (42 vs. 22 months; p = 0.006). The median 2nd-line PFS (14 vs. 4 months, p < 0.001) and 3rd-line PFS (4 vs. 2 months, p = 0.012) were significantly better in the DOC group than in the ABI group. Among the unmatched cohort, after ABI for mHSPC, the median 2nd-line PFS did not differ between the patients treated with DOC and those treated with enzalutamide as 2nd-line therapy (both 3 months, p = 0.8).

CONCLUSIONS

ADT with DOC or ABI has comparable oncologic outcomes in terms of OS, CSS, and PFS2 in patients with de novo high-risk mHSPC. Compared to DOC, ABI resulted in longer time to CRPC but worse 2nd and 3rd-line PFS. Further studies are needed to clarify the optimal sequence of therapy in the upfront intensive treatment era.

Triplet Therapy in Metastatic Castrate Sensitive Prostate Cancer (mCSPC)-A Potential New Standard of Care

The treatment paradigm for metastatic castrate-sensitive prostate cancer (mCSPC) has evolved rapidly in the past decade with the approval of several life-prolonging therapies including docetaxel chemotherapy and multiple androgen receptor pathway inhibitors (ARPI) in combination with androgen deprivation therapy (ADT). Recently reported phase-three trials have demonstrated a survival benefit of upfront triplet therapy with ADT, docetaxel plus either abiraterone acetate or darolutamide when compared to ADT plus docetaxel alone. However, multiple questions including the incremental benefit of docetaxel to a combination of ADT and ARPI, the timing of ARPI, optimal patient selection for triplet therapy and clinical and genomic biomarkers still remain to be answered. Moreover, real-world data suggest suboptimal treatment intensification with many patients treated with ADT alone highlighting challenges in implementation. In this article, we review the phase-three data associated with triplet therapy in mCSPC. We also discuss the knowledge gaps that exist despite the completion of these studies and how ongoing studies are likely to change the paradigm in the near future. Finally, we provide a simple algorithm based on current data that clinicians can use in daily practice to select patients for appropriate treatment strategies.

Role of multidisciplinary team meetings in implementation of chemohormonal therapy in metastatic prostate cancer in daily practice

BACKGROUND

The recommended treatment for a subset of patients with metastatic prostate cancer (mPC) changed from androgen deprivation therapy (ADT) to combinations with chemotherapy such as docetaxel. Implementation of new evidence from trials is however complex and challenging. We investigated the effect of multidisciplinary team meetings (MDTs) on adopting the newest emerging combination therapy in patients with mPC and assessed the overall survival of chemohormonal therapy in a real-world setting.

METHODS

All mPC patients diagnosed between October 2015 and April 2016 in the Netherlands were identified from the population-based Netherlands Cancer Registry (n = 962). Logistic regression analyses were performed to examine the role of patient- and tumor characteristics, with special emphasis on MDTs, on receiving chemohormonal therapy versus ADT monotherapy. Kaplan-Meier survival curves were used to assess overall survival (OS).

RESULTS

As many patients received ADT monotherapy as chemohormonal therapy (both n = 452). Being discussed in a MDT as patient, younger age, less comorbidities, a better performance status and high-volume disease were significantly associated with receiving chemohormonal therapy compared to ADT monotherapy. After adjustment for these factors, the presence of a MDT was independently associated with the administration of chemohormonal therapy (OR 2.77, 95% CI 1.68-4.59). The 2-year OS was 82.1% (95% CI: 78.5-85.6%) for patients receiving chemohormonal therapy and 59.9% (95% CI: 55.4-64.4%) for patients receiving ADT monotherapy.

CONCLUSION

Being discussed in a MDT is independently associated with the administration of chemohormonal therapy in this group of patients with mPC. This supports the hypothesis that implementation of innovative treatment options is facilitated by an organizational structure with MDTs.

[Androgen deprivation therapy ± new antihormonal therapy for the treatment of metastatic hormone-sensitive prostate cancer]

BACKGROUND

From 1941 to 2014, metastatic hormone-sensitive prostate cancer (mHSPC) was solely treated by surgery or medical castration (androgen deprivation therapy [ADT]). In 2014, the addition of docetaxel chemotherapy (CTX) was shown to significantly improve overall survival. However, CTX is not ideal for all patients. Some are too old, too sick, or oppose to treatment with CTX. Therefore, alternatives with low toxicity and equal efficacy were explored. Abiraterone (Abi), apalutamide (Apa), and enzalutamide (Enza) are new antihormonal therapies (NHT) which meet these requirements.

OBJECTIVES

To review the role of NHTs + ADT in mHSPC.

MATERIALS AND METHODS

Prerequisites and challenges are summarized and key data on combination therapy with NHTs + ADT in mHSPC are reviewed.

RESULTS

Treatment of mHSPC with Abi, Apa, or Enza represents a big step forward. Especially for patients who do not qualify for CTX or oppose CTX, NHTs are a valid alternative. The use of Abi is more challenging than the use of Apa and Enza due to more complex conditions that need to be fulfilled for its use. Thus, the time for the patient in the mHSPC stage will be longer with more intensive androgen deprivation, which may lead to increased risk of cardiovascular disease and osteoporosis. When choosing a treatment with NHTs in this setting, possible follow-up treatment needs to be considered.

CONCLUSIONS

Treatment of mHSPC using NHTs + ADT is an important new standard. Almost every patient can be treated with one of the NHTs with relatively low risk of toxicity. Therefore, these treatments are widely used. In the future, the addition of new therapeutics could further strengthen the relevance of NHTs in the mHSPC setting.

Effectiveness of Adding Docetaxel to Androgen Deprivation Therapy for Metastatic Hormone-Sensitive Prostate Cancer in Korean Real-World Practice

PURPOSE

Evidence in favor of adding docetaxel in treatment of metastatic hormone-sensitive prostate cancer (mHSPC) has led to docetaxel in conjunction with androgen deprivation therapy (ADT) as standard therapy. The aim of this study was to examine the effectiveness of docetaxel with ADT for Korean patients with mHSPC in real-world practice.

MATERIALS AND METHODS

A retrospective cohort study was performed at six Korean hospitals for patients with mHSPC treated with docetaxel plus ADT. Patients were treated every 3 weeks for up to six cycles with 75 mg/m² of docetaxel. The primary endpoint was time to castration resistant prostate cancer (CRPC).

RESULTS

This study included 46 eligible patients from June 2016 to February 2021. Median age was 68.5 years (range, 52-84) and all patients present with de novo M1 with high-volume disease. The median prostate-specific antigen (PSA) level at ADT initiation was 205.4 (7.7-1933) ng/mL, and time from ADT to docetaxel was 2.4 months (0-5.3). All six planned cycles of docetaxel were delivered in 36 patients (78%), 7 patients (15%) discontinued treatment due to adverse events, and 3 patients (7%) discontinued due to progression. At the time of the analysis, CRPC had developed in 34 patients (74%), and the median time to CRPC was 18.0 (95% confidence interval, 14.1-21.9) months. PSA <0.2 ng/mL was achieved in 11 patients (24%) after 6 months of ADT and in 10 patients (22%) after 12 months. At last follow-up, 35 patients (76%) were alive; the median overall survival was not reached.

CONCLUSION

The effect of docetaxel combined with ADT for Korean patients with mHSPC is comparable with prior results in Western studies.

Comparison of doublet and triplet therapies for metastatic hormone-sensitive prostate cancer: A systematic review and network meta-analysis

Background

The best choice of first-line treatment for metastatic hormone-sensitive prostate cancer (mHSPC) is unclear. We aimed to compare the effectiveness and safety determined in randomized clinical trials of doublet and triplet treatments for mHSPC.

Methods

Medline, Embase, Cochrane Central and ClinicalTrials.gov were searched from inception through July 01, 2022. Eligible studies were phase III randomized clinical trials evaluating androgen deprivation treatment (ADT) alone, doublet therapies [ADT combined with docetaxel (DOC), novel hormonal agents (NHAs), or radiotherapy (RT)], or triplet therapies (NHA+DOC+ADT) as first-line treatments for mHSPC. Outcomes of interest included overall survival (OS), progression-free survival (PFS) and grades 3-5 adverse events (AEs). Subgroup analyses were performed based on tumor burden. The effects of competing treatments were assessed by Bayesian network meta-analysis using R software.

Results

Ten trials with 12,298 patients comparing nine treatments were included. Darolutamide (DARO) +DOC+ADT ranked best in terms of OS benefits (OR 0·52 [95% CI 0·39-0·70]), but its advantages were all statistically insignificant compared with other therapy options except for DOC+ADT (OR 0·68 [95% CI 0·53-0·88]) and RT+ADT (OR 0·57 [95% CI 0·40-0·80]). In terms of PFS, enzalutamide(ENZA)+DOC+ADT (OR 0·32 [95% CI 0·24-0·44]) and abiraterone and prednisone (AAP) +DOC+ADT (OR 0·33 [95% CI 0·25-0·45]) ranked best. For patients with high volume disease (HVD), low volume disease (LVD), and visceral metastases, the optimal therapies were AAP+DOC+ADT (OR 0·52 [95% CI 0·33-0·83]), apalutamide+ADT (OR 0·52 [95% CI 0·26-1·05]) and DARO+DOC+ADT (OR 0·42 [95% CI 0·13-1·34]), respectively. For safety, AAP+DOC+ADT (OR 3·56 [95% CI 1·51-8·43]) ranked worst with the highest risk of grade 3-5 AEs.

Conclusions

Triple therapies may further improve OS and PFS but may be associated with a decrease in safety. Triplet therapies could be suggested for HVD patients, while doublet combinations should still be preferred for LVD patients.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPEROFILES/303117_STRATEGY_20220202.pdf, identifier CRD4202303117.

Comparison of efficacy and medical costs between upfront docetaxel and abiraterone treatments of metastatic hormone-sensitive prostate cancer patients in real-world practice: a multicenter retrospective study

PURPOSE

We compared the real-world efficacy and medical costs for treatment with upfront docetaxel (DOC) and abiraterone acetate (ABI) up to progression-free survival 2 (PFS2) in patients with metastatic hormone-sensitive prostate cancer (mHSPC).

METHODS

This multicenter retrospective study included 340 patients with mHSPC treated with either upfront DOC or upfront ABI between October 2015 and December 2021. We compared PFS2 and medical costs between the two treatment groups. PFS2 was defined as the time from first-line therapy to progression on second-line therapy. Medical costs were estimated using the National Health Insurance drug prices in 2022 in Japan.

RESULTS

The upfront DOC and ABI groups included 107 and 233 patients, respectively. The incidence of metastatic castration-resistant PC progression was significantly higher in the upfront DOC group compared with the incidence in the upfront ABI group. However, no significant differences in PFS2 were observed between the two treatment groups. Monthly medical costs per patient were significantly higher in the upfront ABI group ($3453) compared with the costs in the upfront DOC group ($1239, P < 0.001). The cost differences were significantly influenced by differences in the length of androgen deprivation therapy monotherapy (DOC group, 13.4 months vs. ABI group, 0.0 months).

CONCLUSIONS

We observed a significant cost benefit in the upfront DOC group in Japanese real-world practice, while the PFS2 rates were similar between the groups. Upfront DOC was a more cost-effective option for men with mHSPC who were eligible for toxic chemotherapy.

Combination therapy for high-volume versus low-volume metastatic hormone-sensitive prostate cancer: A systematic review and network meta-analysis

Purpose: To conduct a systematic review and network meta-analysis (NMA) to compare the efficacy of currently available combination therapies in patients with metastatic hormone-sensitive prostate cancer (mHSPC). Methods: Qualified publications were searched in the PubMed, Embase, and Cochrane CENTRAL databases. Overall survival (OS) and radiographic progression-free survival (rPFS) were indirectly compared and assessed using NMA and the surface under the cumulative ranking curve, respectively. Adverse events (AEs) were also compared. Results: Eighteen publications from 12 trials were analyzed in the NMA. In the overall population, triplet therapy was ranked first for OS (hazard ratio [HR]: 0.57, 95% credible interval [CrI]: 0.48-0.67) and rPFS (HR: 0.33, 95% CrI:0.26-0.41) compared with androgen deprivation therapy (ADT) with or without standard non-steroidal antiandrogen. In high-volume mHSPC, triplet therapy was also ranked first in OS (HR, 0.57; 95% CrI:0.44-0.75) and rPFS(HR, 0.29; 95% CrI: 0.23-0.37). Specifically, abiraterone triplet therapy was ranked first in OS (HR, 0.52; 95% CrI:0.38-0.72) and rPFS (HR, 0.28; 95% CrI:0.21-0.38) among all therapies. ADT plus rezvilutamide was ranked first among doublet therapies (OS: HR, 0.58; 95% CrI:0.44-0.77; rPFS: HR, 0.44; 95% CrI:0.33-0.58). In low-volume mHSPC, doublet and triplet therapies were ranked first in OS (HR:0.68, 95% CrI:0.58-0.80) and rPFS (HR:0.37, 95% CrI:0.25-0.55), respectively. ADT plus apalutamide was ranked first in OS among all therapies (HR:0.53, 95% CrI:0.35-0.79), whereas enzalutamide triplet therapy was ranked first in rPFS (HR:0.27, 95% CrI:0.15-0.51). ADT plus rezvilutamide showed a relatively lower incidence of AE among all therapies (OR:1.00, 95% CrI:0.31-3.15), and a lower risk of specific AEs among doublet therapies, particularly regarding seizure (OR, 0.29; 95% CrI:0.01-8.18) and fatigue (OR, 0.96; 95% CrI:0.63-1.46). Docetaxel-based doublet or triplet therapies significantly increased the risk of any AEs or grade ≥3 AEs. Conclusion: Triplet therapy was the best treatment option for the overall population. In high-volume mHSPC, triplet therapy and ADT plus rezvilutamide had the greatest potential to benefit patients. Patients with low-volume mHSPC were most likely to benefit from ADT plus androgen receptor-targeted agents. Triplet therapy was associated with a higher risk of AEs than the other therapies. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022375347, identifier PROSPERO:CRD42022375347.

Duplicated network meta-analysis in advanced prostate cancer: a case study and recommendations for change

BACKGROUND

Research overlap and duplication is a recognised problem in the context of both pairwise and network systematic reviews and meta-analyses. As a case study, we carried out a scoping review to identify and examine duplicated network meta-analyses (NMAs) in a specific disease setting where several novel therapies have recently emerged: hormone-sensitive metastatic prostate cancer (mHSPC).

METHODS

MEDLINE and EMBASE were systematically searched, in January 2020, for indirect or mixed treatment comparisons or network meta-analyses of the systemic treatments docetaxel and abiraterone acetate in the mHSPC setting, with a time-to-event outcome reported on the hazard-ratio scale. Eligibility decisions were made, and data extraction performed, by two independent reviewers.

RESULTS

A total of 13 eligible reviews were identified, analysing between 3 and 8 randomised comparisons, and comprising between 1773 and 7844 individual patients. Although the included trials and treatments showed a high degree of overlap, we observed considerable variation between identified reviews in terms of review aims, eligibility criteria and included data, statistical methodology, reporting and inference. Furthermore, crucial methodological details and specific source data were often unclear.

CONCLUSIONS AND RECOMMENDATIONS

Variation across duplicated NMAs, together with reporting inadequacies, may compromise identification of best-performing treatments. Particularly in fast-moving fields, review authors should be aware of all relevant studies, and of other reviews with potential for overlap or duplication. We recommend that review protocols be published in advance, with greater clarity regarding the specific aims or scope of the project, and that reports include information on how the work builds upon existing knowledge. Source data and results should be clearly and completely presented to allow unbiased interpretation.

Addition of New Androgen Receptor Pathway Inhibitors to Docetaxel and Androgen Deprivation Therapy in Metastatic Hormone-Sensitive Prostate Cancer: A Systematic Review and Metanalysis

In recent years, significant changes have occurred in metastatic hormone-sensitive prostate cancer (mHSPC) management, where docetaxel and new androgen receptor pathway inhibitors (ARPI) have been shown to improve overall survival (OS) compared to androgen deprivation therapy (ADT). Recent data could once again radically change mHSPC treatment. PEACE-1 and ARASENS trials demonstrated a survival benefit of the addition of ARPI to docetaxel and ADT combination (triplet therapy), compared to docetaxel and ADT. With multiple options to choose from, it is crucial to identify the patients who would benefit most from triplet therapy. In this meta-analysis, we evaluated the activity of the triplet therapy versus docetaxel plus ADT in mHSPC. A systematic review of PubMed/Medline, Embase, and the proceedings of major international meetings was performed. Five RCTs fulfilled the inclusion criteria. PEACE-1 and ARASENS studies reported disease-free survival (DFS) and OS. Post hoc analysis of three other trials evaluated the combination of ARPI, docetaxel and ADT. Globally, 2538 patients were included (1270 triplet therapy; 1268 docetaxel + ADT). Triplet therapy was associated with improved OS (hazard ratio (HR) 0.74; 95% confidence interval (CI), 0.66-0.83, p < 0.00001). A statistically significant benefit was shown in high-volume mHSPC patients (HR 0.76; 95% CI 0.59-0.97, p = 0.03) and in patients with de novo metastatic disease (HR 0.73; 95% CI, 0.64-0.82, p < 0.00001). The addition of ARPI to standard therapy was associated with DFS improvement (HR 0.41; 95% CI, 0.35-0.49, p < 0.00001). This metanalysis shows a significant OS benefit from concomitant administration of ARPI, docetaxel and ADT in high volume and de novo mHSPC.

Emergence of triplet therapy for metastatic castration-sensitive prostate cancer: An updated systematic review and network meta-analysis

INTRODUCTION

There have been a growing number of treatment options available for men with metastatic castration-sensitive prostate cancer. Not only have newer agents entered the clinical landscape, there is a trend toward treatment intensification by combining multiple agents simultaneously. We aim to assess the best contemporary treatment option for men with mCSPC.

MATERIALS AND METHODS

We perform an updated systematic review and network meta-analysis of randomized control trials that evaluated systemic therapies in men with castration-sensitive prostate cancer. We searched multiple databases up to April 2022. We included all randomized trials assessing the effect of systemic agents. We performed subgroup analyses based on disease volume and timing of presentation. Statistical analysis was performed with Bayesian methods.

RESULTS

We found 10 eligible trials with 10,065 patients who were included in this analysis. Triplet therapy with darolutamide or abiraterone with docetaxel and ADT improved overall survival. In the sensitivity analysis, the respective hazard ratios for triplet therapy was HR 0.70 (95%CI 0.61-0.80) compared to docetaxel+ADT and 0.77 (95%CI 0.65-0.91) compared to androgen receptor pathway inhibitors+ADT combinations. It was estimated that there was 96% chance that one of the triplet therapy combinations were the best treatment option from an OS perspective. Triplet therapy also improved progression-free survival. These benefits were pronounced in men with high-volume disease burden and those with de novo metastatic disease.

CONCLUSION

The finding suggest that triplet therapy is likely the most efficacious available option in men with metastatic, castration-sensitive prostate cancer, especially in those with high-volume disease burden.

Does castration status affect docetaxel-related adverse events? :Identification of risk factors for docetaxel-related adverse events in metastatic prostate cancer

BACKGROUND

Docetaxel-related adverse events (AEs) such as neutropenia and febrile neutropenia (FN) can be life-threatening. A previous in vivo study raised the hypothesis that the castration status affects the rate of hematologic AEs. We aimed to investigate the impact of castration status on the incidence of docetaxel-related AE in metastatic prostate cancer (mPCa) patients.

METHODS

We retrospectively analyzed the records of 265 mPCa patients treated with docetaxel, comprising 92 patients with metastatic hormone-sensitive prostate cancer (mHSPC) and 173 patients with metastatic castration-resistant prostate cancer (mCRPC) between January 2015 and December 2021. Common terminology Criteria for Adverse Events (CTCAE) was applied to evaluate AEs. We analyzed the differential incidences between mHSPC and mCRPC, and risk factors of hematologic and nonhematologic AEs using a logistic regression model.

RESULTS

The rate of patients who received primary prophylaxis against neutropenia was higher in those with the mHSPC compared with those with the mCRPC (7.5% vs. 33%, p < 0.001). Among the patients without primary prophylaxis, incidence rates of severe neutropenia (CTCAE ≥ Grade3) and FN were 89% and 16% in patients with mCRPC compared to 81% and 18% in those with mHSPC. Logistic regression analysis revealed that age ≥ 75 years and failure to provide primary prophylaxis were independent risk factors of severe neutropenia (odds ratio [OR]: 2.39, 95% confidential interval [CI]: 1.10-5.18 and OR: 15.8, 95% CI: 7.23-34.6, respectively). Eastern Cooperative Oncology Group Performance Status (ECOG-PS) ≧ 1 was an independent risk factor of FN (OR: 2.26, 95% CI: 1.13-4.54). Castration status (mHSPC vs. mCRPC) was not associated with the risks of severe neutropenia and FN.

CONCLUSIONS

Castration status did not affect the risk of severe neutropenia or FN in mPCa patients treated with docetaxel regardless of the disease state. Failure to provide primary prophylaxis and advanced patient age are independent risk factors of severe neutropenia; while patients with poor PS are more likely to develop FN. These findings may help guide the clinical decision-making for proper candidate selection of docetaxel treatment.

HOW TO OPTIMALLY SEQUENCE AVAILABLE THERAPY LINES IN ADVANCED PROSTATE CANCER

Optimal sequencing of available therapy lines in patients with advanced prostate cancer often poses quite a challenge. The guidelines are sometimes equivocal and clinical trial data are not always applicable to a particular patient. There is a difference in availability of therapy options throughout the world. In decision making, a patient as a whole should be taken into consideration, not just the stage and biology of the disease, but also patient's age, performance status, comorbidities, previous therapy lines, drug's safety profile and patient's preferences. This review article will show certain therapeutic options in the treatment of advanced hormone-sensitive prostate cancer and castration resistant prostate cancer: non- metastatic and metastatic. An attempt will be made to clarify the optimal sequencing.

Analysis of adaptive platform trials using a network approach

BACKGROUND

Adaptive platform trials allow randomized controlled comparisons of multiple treatments using a common infrastructure and the flexibility to adapt key design features during the study. Nonetheless, they have been criticized due to the potential for time trends in the underlying risk level of the population. Such time trends lead to confounding between design features and risk level, which may introduce bias favoring one or more treatments. This is particularly true when experimental treatments are not all randomized during the same time period as the control, leading to the potential for bias from non-concurrent controls.

METHODS

Two analysis methods addressing this bias are stratification and adjustment. Stratification uses only comparisons between treatment cohorts randomized during identical time periods and does not use non-concurrent randomizations. Adjustment uses a modeled analysis including time period adjustment, allowing all data to be used, even from periods without concurrent randomization. We show that these competing approaches may be embedded in a common framework using network meta-analysis principles. We interpret the stages between adaptations in a platform trial as separate fixed design trials. This allows platform trials to be viewed as networks of direct randomized comparisons and indirect non-randomized comparisons. Network meta-analysis methodology can be re-purposed to aggregate the total information from a platform trial and to transparently decompose this total information into direct randomized evidence and indirect non-randomized evidence. This allows sensitivity to indirect information to be assessed and the two analysis methods to be clearly compared.

RESULTS

Simulations of platform trials were analyzed using a network approach implemented in the netmeta package in R. The results demonstrated bias of unadjusted methods in the presence of time trends in risk level. Adjustment and stratification were both unbiased when direct evidence and indirect evidence were consistent. Network tests of inconsistency may be used to diagnose inconsistency when it exists. In an illustrative network analysis of one of the treatment comparisons from the STAMPEDE platform trial in metastatic prostate cancer, indirect comparisons using non-concurrent controls were inconsistent with the information from direct randomized comparisons. This supports the primary analysis approach of STAMPEDE, which used only direct randomized comparisons.

CONCLUSION

Network meta-analysis provides a natural methodology for analyzing the network of direct and indirect treatment comparisons from a platform trial. Such analyses provide transparent separation of direct and indirect evidence, allowing assessment of the impact of non-concurrent controls. We recommend time-stratified analysis of concurrently controlled comparisons for primary analyses, with time-adjusted analyses incorporating non-concurrent controls reserved for secondary analyses. However, regardless of which methodology is used, a network analysis provides a useful supplement to the primary analysis.

Addition of androgen receptor targeted agents to androgen deprivation therapy and docetaxel in metastatic hormone-sensitive prostate cancer: a systematic review and meta-analysis

Background

Androgen-deprivation therapy (ADT) historically represented the milestone for the treatment of metastatic hormone-sensitive prostate cancer (mHSPC). Recently, combining androgen receptor-targeted agents (ARTA) or docetaxel with ADT significantly improved clinical outcomes in this setting. The efficacy of the combined use of an ARTA with docetaxel and ADT (triplet), however, was unknown, and often conflicting data derived from subgroup analysis of randomized phase III trials. In order to better define the benefits and risks of the triplet in mHSPC, we carried out a systematic review and meta-analysis of available clinical trials.

Methods

A literature search with no data restriction using Medline/PubMed, the Cochrane Library, and American Society of Clinical Oncology/European Society for Medical Oncology (ASCO/ESMO) Meeting abstracts was carried out up to April 2022. The meta-analysis was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statements. Overall survival (OS) was the primary endpoint; progression-free survival (PFS) and safety were secondary endpoints. For OS and PFS, summary hazard ratios (HRs) were calculated; for safety, risk ratio (RR) was assessed. Random- or fixed-effects models were used, depending on studies heterogeneity.

Results

Five randomized clinical trials fulfilled the prespecified inclusion criteria. The triplet significantly improved OS (fixed-effect, HR = 0.74; P < 0.00001) and PFS (fixed-effect; HR = 0.50 for clinical PFS, HR = 0.49 for radiological PFS; P < 0.0001) compared with docetaxel plus ADT. We did not show heterogeneity between treatment efficacy and the disease burden, metachronous versus synchronous presentation, concomitant versus sequential strategy. Compared with docetaxel + ADT, the triplet did not increase the risk of adverse events (AEs) (RR = 1.00, P = 0.27 for any-grade AEs; RR = 1.13, P = 0.14 for severe AEs), except for severe hypertension (RR = 1.73, P = 0.001).

Conclusions

Emerging evidence supports the combination of an ARTA plus docetaxel and ADT in mHSPC patients. Given the availability of several strategies in this setting, clinical characteristics and drug safety profile may help clinicians select the appropriate treatment for mHSPC patients who are more likely to benefit from treatment intensification.

•

The addition of ARTA or docetaxel to ADT improved survival in mHSPC.

•

Recently, the combination of ARTA plus docetaxel and ADT (triplet) versus docetaxel plus ADT has been investigated.

•

The triplet prolonged OS and PFS compared with docetaxel plus ADT and represents a potential practice-changing treatment.

•

Clinical characteristics and drug safety profile may help clinicians to select the appropriate treatment for mHSPC.

Practical guidance for running late-phase platform protocols for clinical trials: lessons from experienced UK clinical trials units

BACKGROUND

Late-phase platform protocols (including basket, umbrella, multi-arm multi-stage (MAMS), and master protocols) are generally agreed to be more efficient than traditional two-arm clinical trial designs but are not extensively used. We have gathered the experience of running a number of successful platform protocols together to present some operational recommendations.

METHODS

Representatives of six UK clinical trials units with experience in running late-phase platform protocols attended a 1-day meeting structured to discuss various practical aspects of running these trials. We report and give guidance on operational aspects which are either harder to implement compared to a traditional late-phase trial or are specific to platform protocols.

RESULTS

We present a list of practical recommendations for trialists intending to design and conduct late-phase platform protocols. Our recommendations cover the entire life cycle of a platform trial: from protocol development, obtaining funding, and trial set-up, to a wide range of operational and regulatory aspects such as staffing, oversight, data handling, and data management, to the reporting of results, with a particular focus on communication with trial participants and stakeholders as well as public and patient involvement.

DISCUSSION

Platform protocols enable many questions to be answered efficiently to the benefit of patients. Our practical lessons from running platform trials will support trial teams in learning how to run these trials more effectively and efficiently.

The Treatment of Metastatic, Hormone-Sensitive Prostatic Carcinoma

BACKGROUND

For many years, the standard treatment of metastatic, hormone-sensitive prostatic carcinoma (mHSPC) was androgen deprivation therapy (ADT) alone. By lowering the testosterone level into the castration range, ADT deprives the tumor of a key growth factor.

METHODS

For this article, we evaluated the treatment recommendations contained in national and international guidelines (German S3 guidelines and those of the European Society for Medical Oncology [ESMO], European Association of Urology [EAU], and National Comprehensive Cancer Network [NCCN]), as well as pertinent publications revealed by a PubMed search and the congress abstracts of the ESMO and of the American Society of Clinical Oncology [ASCO].

RESULTS

The past few years have witnessed fundamental changes in the treatment of mHSPC. Treatment intensification with docetaxel or with the new drugs directed against the androgen receptor signal pathway (abiraterone, apalutamide and enzalutamide) has been found to lower mortality by 19-40% and is now an integral component of first-line therapy. Relevant new findings have also been obtained with threefold combinations of ADT, docetaxel, and abiraterone or darolutamide. For patients with a light tumor burden, local radiotherapy of the primary tumor improves the probability of survival at 3 years by 8% (45.4 versus 49.1 months, difference 3.6 months; 95% confidence interval, 1.0 to 6.2 months).

CONCLUSION

The treatment of mHSPC is constantly changing. Phase III trials that are now in the recruitment stage, as well as our continually improving understanding of the underlying molecular-pathological mechanisms, will be altering the treatment landscape still further in the years to come.

Management of de novo metastatic hormone-sensitive prostate cancer: A comprehensive report of a single-center experience

Background

Upfront docetaxel or novel hormonal agents (NHA) such as abiraterone and enzalutamide have become the standard of care for metastatic hormone sensitive prostate cancer (mHSPC). We evaluated real-world management of patients treated with these agents at a single center.

Patients and methods

Patients with de novo mHSPC treated with upfront docetaxel or an NHA between January 2014 and April 2019 at Mount Sinai Health System were included. We evaluated time to next treatment (TTNT), PSA progression free survival (PFS) and overall survival (OS) after initial treatment with these drugs. Kaplan Meier method and multivariable Cox proportional hazards models were used for analysis. We additionally assessed the prognostic value of post-treatment PSA.

Results

We identified 94 de novo mHSPC patients; 52 and 42 treated with upfront docetaxel and NHAs, respectively. NHAs were associated with a median TTNT of 20.7 months compared to 10.1 months with docetaxel (log-rank p = 0.023). We also observed median PSA PFS of 19 months for NHAs and 13.2 months for docetaxel (p = 0.069). However, OS between the two treatment groups was unchanged. Among docetaxel treated patients, TTNT was shorter among those with high metastasis burden (9.63 vs 25.5 months, p = 0.026) which was not observed among NHA treated patients (25.1 vs 20.7 months, p = 0.79). Regardless of treatment, lower post-treatment PSA levels were associated with improved TTNT (58.95 vs. 11.57 vs. 9.4 months for PSA ≤0.2, 0.2–0.4, >0.4ng/ml, respectively; p<0.001)

Conclusion

Real world data demonstrated a shorter duration of treatment with docetaxel than NHAs, reflecting the time-limited nature of docetaxel regimens compared to the treat-till-progression approach of NHAs. While TTNT was generally longer for NHAs than docetaxel, some docetaxel-treated patients achieved significant periods of time off treatment. In addition, the depth of PSA response following combination treatment may hold prognostic value for mHSPC outcomes.

Androgen Receptor Signaling Inhibitors in Addition to Docetaxel with Androgen Deprivation Therapy for Metastatic Hormone-sensitive Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Recent randomized controlled trials (RCTs) examined the role of adding androgen receptor signaling inhibitors (ARSIs), including abiraterone acetate (ABI), apalutamide, darolutamide (DAR), and enzalutamide (ENZ), to docetaxel (DOC) and androgen deprivation therapy (ADT) in patients with metastatic hormone-sensitive prostate cancer (mHSPC).

OBJECTIVE

To analyze the oncologic benefit of triplet combination therapies using ARSI + DOC + ADT, and comparing them with available treatment regimens in patients with mHSPC.

EVIDENCE ACQUISITION

Three databases and meetings abstracts were queried in April 2022 for RCTs analyzing patients treated with first-line combination systemic therapy for mHSPC. The primary interests of measure were overall survival (OS) and progression-free survival (PFS). Subgroup analyses were conducted to assess the differential outcomes in patients with low- and high-volume disease as well as de novo and metachronous metastasis.

EVIDENCE SYNTHESIS

Overall, 11 RCTs were included for meta-analyses and network meta-analyses (NMAs). We found that the triplet combinations outperformed DOC + ADT in terms of OS (pooled hazard ratio [HR]: 0.74, 95% confidence interval [CI]: 0.65-0.84) and PFS (pooled HR: 0.49, 95% CI: 0.42-0.58). There was no statistically significant difference between patients with low- and high-volume disease in terms of an OS benefit from adding an ARSI to DOC +ADT (both HR: 0.79; p = 1). Based on NMAs, triplet therapy also outperformed ARSI + ADT in terms of OS (DAR + DOC + ADT: pooled HR: 0.74, 95% CI: 0.55-0.99) and PFS (ABI + DOC + ADT: HR: 0.68, 95% CI: 0.51-0.91, and ENZ + DOC + ADT: HR: 0.70, 95% CI: 0.53-0.93). An analysis of treatment ranking among de novo mHSPC patients showed that triplet therapy had the highest likelihood of improved OS in patients with high-volume disease; however, doublet therapy using ARSI + ADT had the highest likelihood of improved OS in patients with low-volume disease.

CONCLUSIONS

We found that the triplet combination therapy improves survival endpoints in mHSPC patients compared with currently available doublet treatment regimens. Our findings need to be confirmed in further head-to-head trials with longer follow-up and among various patient populations.

PATIENT SUMMARY

Our study suggests that triplet therapy with androgen receptor signaling inhibitor, docetaxel, androgen deprivation therapy prolongs survival in patients with metastatic hormone-sensitive prostate cancer compared with the current standard doublet therapy.

Sequencing impact and prognostic factors in metastatic castration-resistant prostate cancer patients treated with cabazitaxel: A systematic review and meta-analysis

BACKGROUND

Cabazitaxel is an effective treatment of post-docetaxel metastatic castration-resistant prostate cancer (mCRPC). We aimed to assess the sequencing impact and identify prognostic factors of oncologic outcomes in mCRPC patients treated with cabazitaxel.

METHODS

PUBMED, Web of Science, and Scopus databases were searched for articles published before January 2022 according to the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) statement. Studies were deemed eligible if they investigated pretreatment clinical or hematological prognostic factors of overall survival (OS) in mCRPC patients with progression after docetaxel treated with available treatments including cabazitaxel.

RESULTS

Overall, 22 studies were eligible for the meta-analysis. In mCRPC patients treated with docetaxel, subsequent treatment with cabazitaxel was associated with better OS compared to that without cabazitaxel (pooled hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.56-0.89). Among the patients treated with cabazitaxel, several pretreatment clinical features and hematologic biomarkers were associated with worse OS as follows: poor performance status (PS) (pooled HR: 1.92, 95% CI: 1.33-2.77), presence of visceral metastasis (pooled HR: 2.13, 95% CI: 1.62-2.81), symptomatic disease (pooled HR: 1.47, 95% CI: 1.25-1.73), high PSA (pooled HR: 1.76, 95% CI: 1.27-2.44), high alkaline phosphatase (ALP) (pooled HR: 1.45, 95% CI: 1.28-1.65), high lactate dehydrogenase (LDH) (pooled HR: 1.54, 95% CI: 1.00-2.38), high c-reactive protein (CRP) (pooled HR: 4.40, 95% CI: 1.52-12.72), low albumin (pooled HR:1.09, 95% CI: 1.05-1.12) and low hemoglobin (pooled HR:1.55, 95% CI: 1.20-1.99).

CONCLUSIONS

Sequential therapy with cabazitaxel significantly improves OS in post-docetaxel mCRPC patients. In mCRPC patients treated with cabazitaxel, patients with poor PS, visceral metastasis, and symptomatic disease were associated with worse OS. Further, pretreatment high PSA, ALP, LDH or CRP as well as low hemoglobin or albumin, were blood-based prognostic factors for OS. These findings might help guide the clinical decision-making for the use of cabazitaxel and prognostication of its OS benefit.

Abiraterone acetate plus prednisolone for metastatic patients starting hormone therapy: 5-year follow-up results from the STAMPEDE randomised trial (NCT00268476)

Abiraterone acetate plus prednisolone (AAP) previously demonstrated improved survival in STAMPEDE, a multiarm, multistage platform trial in men starting long-term hormone therapy for prostate cancer. This long-term analysis in metastatic patients was planned for 3 years after the first results. Standard-of-care (SOC) was androgen deprivation therapy. The comparison randomised patients 1:1 to SOC-alone with or without daily abiraterone acetate 1000 mg + prednisolone 5 mg (SOC + AAP), continued until disease progression. The primary outcome measure was overall survival. Metastatic disease risk group was classified retrospectively using baseline CT and bone scans by central radiological review and pathology reports. Analyses used Cox proportional hazards and flexible parametric models, accounting for baseline stratification factors. One thousand and three patients were contemporaneously randomised (November 2011 to January 2014): median age 67 years; 94% newly-diagnosed; metastatic disease risk group: 48% high, 44% low, 8% unassessable; median PSA 97 ng/mL. At 6.1 years median follow-up, 329 SOC-alone deaths (118 low-risk, 178 high-risk) and 244 SOC + AAP deaths (75 low-risk, 145 high-risk) were reported. Adjusted HR = 0.60 (95% CI: 0.50-0.71; P = 0.31 × 10^-9 ) favoured SOC + AAP, with 5-years survival improved from 41% SOC-alone to 60% SOC + AAP. This was similar in low-risk (HR = 0.55; 95% CI: 0.41-0.76) and high-risk (HR = 0.54; 95% CI: 0.43-0.69) patients. Median and current maximum time on SOC + AAP was 2.4 and 8.1 years. Toxicity at 4 years postrandomisation was similar, with 16% patients in each group reporting grade 3 or higher toxicity. A sustained and substantial improvement in overall survival of all metastatic prostate cancer patients was achieved with SOC + abiraterone acetate + prednisolone, irrespective of metastatic disease risk group.

Effects of Docetaxel plus Degarelix on Quality of Life and Vascular Endothelial Growth Factor in Patients with Prostate Cancer

Objective. To investigate the effects of docetaxel plus degarelix on quality of life and vascular endothelial growth factor in patients with prostate cancer. Methods. Between 2018 and 2020, 38 patients with castration-resistant prostate cancer (CRPC) treated in our institution were assessed for eligibility and recruited. They were assigned at a ratio of 1 : 1 to receive either docetaxel plus degarelix (observation group) or degarelix (control group). Outcome measures included treatment efficacy, inflammatory factors level, vascular endothelial growth factor (VEGF) level, and quality of life of patients. Results. Docetaxel plus degarelix was associated with a significantly higher treatment efficacy (94.74%, including 9 (47.37%) cases of complete response (CR), 6 (31.58%) cases of partial response (PR), 4 (21.05%) cases of stable disease (SD), and 1 (5.36%) case of progressive disease (PD)) versus degarelix alone (63.16%, including 4 (21.05%) cases of CR, 5 (26.32%) cases of PR, 3 (15.79%) cases of SD, and 7 (36.84%) cases of PD) ( $P<0.05$ ). Before treatment, the two groups showed comparable levels of C-reaction protein (CRP), interleukin- (IL-) 6, and IL-10 ( $P>0.05$ ). Docetaxel plus degarelix resulted in significantly reduced levels of CRP and IL-6 and a significantly higher IL-10 level ( $28.84\pm 5.42$ , $25.31\pm 5.74$ , and $53.32\pm 11.02$ ) versus degarelix alone ( $35.17\pm 6.31$ , $31.54\pm 8.17$ , and $42.76\pm 11.25$ ) ( $P<0.05$ ). There were no significant differences in the urinary function, intestinal function, and hormone function scores between the two groups before treatment ( $P>0.05$ ). The patients receiving docetaxel plus degarelix had higher urinary function, intestinal function, and hormone function scores ( $38.87\pm 4.46$ , $86.51\pm 8.14$ , and $76.65\pm 7.15$ ) versus monotherapy of degarelix ( $29.84\pm 3.58$ , $78.51\pm 7.31$ , and $66.78\pm 6.56$ ) ( $P<0.05$ ). The two groups had similar pretreatment VEGF levels ( $P>0.05$ ). Docetaxel plus degarelix resulted in significantly lower VEGF levels ( $119.17\pm 21.38$ ) versus degarelix ( $124.36\pm 23.14$ ) at 6 months after treatment ( $P<0.05$ ). Conclusion. Docetaxel plus degarelix can enhance the therapeutic efficacy of patients with prostate cancer, mitigate inflammatory response, inhibit the VEGF expression of cancer cells, and improve the patients’ quality of life. Further clinical trials are, however, required prior to general use in clinical practice.

Addition of Docetaxel to Androgen Receptor Axis-targeted Therapy and Androgen Deprivation Therapy in Metastatic Hormone-sensitive Prostate Cancer: A Network Meta-analysis

CONTEXT

Randomized controlled trials (RCTs) have shown that addition of docetaxel or androgen receptor axis-targeted therapy (ARAT) to androgen deprivation therapy (ADT) or addition of ARAT to ADT and docetaxel improves overall survival (OS) in metastatic hormone-sensitive prostate cancer (mHSPC). However, it is unknown whether docetaxel, when given as part of triplet therapy, has an independent OS benefit.

OBJECTIVE

To compare the efficacy of ADT plus ARAT with the triplet of ADT, ARAT, and docetaxel through a network meta-analysis (NMA) of RCTs in mHSPC.

EVIDENCE ACQUISITION

Bibliographic databases and conference proceedings were searched in March 2022 for RCTs that evaluated the addition of docetaxel, ARAT, or both to ADT in mHSPC. The primary endpoint was OS. Standard random-effect NMA and Bayesian analyses were performed to compare ADT plus ARAT with triplet therapy.

EVIDENCE SYNTHESIS

Eleven RCTs (n = 11 546) were eligible. Compared with ADT plus ARAT, the triplet had a nonsignificant OS benefit (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.68-1.16), while ADT plus docetaxel (HR 1.16 [0.94-1.43]) and ADT alone (HR 1.46 [1.30-1.64]) had an increased risk of death. By P-score ordering, the triplet was the most effective treatment strategy (P score = 0.936) followed by ADT plus ARAT (P score = 0.704). The triplet had a 77% likelihood of being the best treatment strategy compared with a 23% likelihood for ADT plus ARAT.

CONCLUSIONS

The triplet of ADT, ARAT, and docetaxel was the highest ranked treatment strategy, but it did not confer a statistically significant OS benefit over ADT plus ARAT. This NMA provides the highest-level comparative evidence for these treatment approaches in the initial management of mHSPC.

PATIENT SUMMARY

We synthesized the available evidence from clinical trials conducted in newly diagnosed metastatic prostate cancer to compare the survival of patients receiving triplet therapy (androgen receptor axis-targeted therapy [ARAT], androgen deprivation therapy [ADT], and docetaxel) with those receiving only ARAT and ADT. We conclude that the triplet is a somewhat more effective treatment approach.

Economic Evaluation of Cost and Time Required for a Platform Trial vs Conventional Trials

IMPORTANCE

Platform trial design allows the introduction of new interventions after the trial is initiated and offers efficiencies to clinical research. However, limited guidance exists on the economic resources required to establish and maintain platform trials.

OBJECTIVE

To compare cost (US dollars) and time requirements of conducting a platform trial vs a series of conventional (nonplatform) trials using a real-life example.

DESIGN, SETTING, AND PARTICIPANTS

For this economic evaluation, an online survey was administered to a group of international experts (146 participants) with publication records of platform trials to elicit their opinions on cost and time to set up and conduct platform, multigroup, and 2-group trials. Using the reported entry dates of 10 interventions into Systemic Therapy in Advancing Metastatic Prostate Cancer: Evaluation of Drug Efficacy, the longest ongoing platform trial, 3 scenarios were designed involving a single platform trial (scenario 1), 1 multigroup followed by 5 2-group trials (scenario 2), and a series of 10 2-group trials (scenario 3). All scenarios started with 5 interventions, then 5 more interventions were either added to the platform or evaluated independently. Simulations with the survey results as inputs were used to compare the platform vs conventional trial designs. Data were analyzed from July to September 2021.

EXPOSURE

Platform trial design.

MAIN OUTCOMES AND MEASURES

Total trial setup and conduct cost and cumulative duration.

RESULTS

Although setup time and cost requirements of a single trial were highest for the platform trial, cumulative requirements of setting up a series of multiple trials in scenarios 2 and 3 were larger. Compared with the platform trial, there was a median (IQR) increase of 216.7% (202.2%-242.5%) in cumulative setup costs for scenario 2 and 391.1% (365.3%-437.9%) for scenario 3. In terms of total cost, there was a median (IQR) increase of 17.4% (12.1%-22.5%) for scenario 2 and 57.5% (43.1%-69.9%) for scenario 3. There was a median (IQR) increase in cumulative trial duration of 171.1% (158.3%-184.3%) for scenario 2 and 311.9% (282.0%-349.1%) for scenario 3. Cost and time reductions in the platform trial were observed in both the initial and subsequently evaluated interventions.

CONCLUSIONS AND RELEVANCE

Although setting up platform trials can take longer and be costly, the findings of this study suggest that having a single infrastructure can improve efficiencies with respect to costs and efforts.

Systemic Therapy for Metastatic Hormone-Sensitive Prostate Cancer: A Randomized Controlled Trial-Based Network Meta-Analysis

Objective

To compare the effects of different treatment strategies for metastatic hormone-sensitive prostate cancer (mHSPC) using a network meta-analysis.

Methods

English databases (PubMed, Embase, and medRxiv) and Chinese databases (Wanfang and CNKI) were searched for randomized controlled trials (RCTs) on the treatment of mHSPC from inception to June 1, 2021. The overall survival (OS) and failure-free survival (FFS) reported by the included studies were extracted from each study for network meta-analysis. Moreover, the priority ranks of the treatment methods were determined.

Results

A total of 18 RCTs with 14,682 patients were included in this study. Androgen-deprivation therapy (ADT) + apalutamide (APA) showed the highest probability of improving the OS (96.2%) and FFS (68.0%). In addition, the patients were stratified into ten subgroups as follows: low/high tumor burden (CHAARTED criteria); Gleason score ≤7/≥8; Eastern Cooperative Oncology Group (ECOG) = 0/≥1; with/without prechemotherapy; and cooperative with/without concomitant radiotherapy. For the improvement of OS, the leading treatments were as follows: (1) ADT + enzalutamide (ENZA) (64.1%)/ADT + abiraterone acetate + prednisone (AAP) (54.3%); (2) ADT + ENZA (41.9%)/ADT + APA (39.2%); (3) ADT + ENZA (39.2%)/ADT + APA (32.1%); (4) ADT + radiotherapy (51%)/ADT + ENZA (76.7%); (5) ADT + AAP (51%)/ADT + AAP (60%).

Conclusion

Three endocrine therapy drugs, abiraterone, enzalutamide, and APA, exhibited the best effects in improving the OS and FFS in all patients and subgroups; however, APA had the most prominent treatment effects. Therefore, ADT + APA should be applied as the common treatment for patients with HSPC based on objective and clinical conditions. Trial Registration. This meta-analysis has been registered on the PROSPERO website (Trial number: https://www.crd.york.ac.uk/prospero/CRD42020221062).