Incorporating Biomarker Stratification into STAMPEDE: an Adaptive Multi-arm, Multi-stage Trial Platform

Treatment in hormone-sensitive metastatic prostate cancer: factors to consider when personalizing therapy

INTRODUCTION

The addition of the androgen-signaling inhibitors (ASI) apalutamide, enzalutamide and abiraterone acetate or docetaxel to standard androgen deprivation therapy (ADT) has been demonstrated to improve overall survival in men with hormone-sensitive metastatic prostate cancer (HSMPC).

AREAS COVERED

The majority of men presenting with metastatic prostate cancer will now benefit from the addition of either a novel ASI or docetaxel to standard ADT. In the absence of comparative studies of these agents, clinicians are left with assessing the individual studies and attempting to individualize therapy.

EXPERT OPINION

ADT with either docetaxel or androgen-signaling inhibitors (ASI) have changed the treatment landscape of HSMPC with clinically meaningful improvement in overall survival compared to ADT alone. Among the factors to consider in the selection of the optimal agent include the volume of disease, performance status and comorbidities, toxicity profile cost and drug availability, and further resistance or sequencing options.

The adaptive designs CONSORT extension (ACE) statement: a checklist with explanation and elaboration guideline for reporting randomised trials that use an adaptive design

Adaptive designs (ADs) allow pre-planned changes to an ongoing trial without compromising the validity of conclusions and it is essential to distinguish pre-planned from unplanned changes that may also occur. The reporting of ADs in randomised trials is inconsistent and needs improving. Incompletely reported AD randomised trials are difficult to reproduce and are hard to interpret and synthesise. This consequently hampers their ability to inform practice as well as future research and contributes to research waste. Better transparency and adequate reporting will enable the potential benefits of ADs to be realised.This extension to the Consolidated Standards Of Reporting Trials (CONSORT) 2010 statement was developed to enhance the reporting of randomised AD clinical trials. We developed an Adaptive designs CONSORT Extension (ACE) guideline through a two-stage Delphi process with input from multidisciplinary key stakeholders in clinical trials research in the public and private sectors from 21 countries, followed by a consensus meeting. Members of the CONSORT Group were involved during the development process.The paper presents the ACE checklists for AD randomised trial reports and abstracts, as well as an explanation with examples to aid the application of the guideline. The ACE checklist comprises seven new items, nine modified items, six unchanged items for which additional explanatory text clarifies further considerations for ADs, and 20 unchanged items not requiring further explanatory text. The ACE abstract checklist has one new item, one modified item, one unchanged item with additional explanatory text for ADs, and 15 unchanged items not requiring further explanatory text.The intention is to enhance transparency and improve reporting of AD randomised trials to improve the interpretability of their results and reproducibility of their methods, results and inference. We also hope indirectly to facilitate the much-needed knowledge transfer of innovative trial designs to maximise their potential benefits. In order to encourage its wide dissemination this article is freely accessible on the BMJ and Trials journal websites."To maximise the benefit to society, you need to not just do research but do it well" Douglas G Altman.

The Adaptive designs CONSORT Extension (ACE) statement: a checklist with explanation and elaboration guideline for reporting randomised trials that use an adaptive design

Adaptive designs (ADs) allow pre-planned changes to an ongoing trial without compromising the validity of conclusions and it is essential to distinguish pre-planned from unplanned changes that may also occur. The reporting of ADs in randomised trials is inconsistent and needs improving. Incompletely reported AD randomised trials are difficult to reproduce and are hard to interpret and synthesise. This consequently hampers their ability to inform practice as well as future research and contributes to research waste. Better transparency and adequate reporting will enable the potential benefits of ADs to be realised.This extension to the Consolidated Standards Of Reporting Trials (CONSORT) 2010 statement was developed to enhance the reporting of randomised AD clinical trials. We developed an Adaptive designs CONSORT Extension (ACE) guideline through a two-stage Delphi process with input from multidisciplinary key stakeholders in clinical trials research in the public and private sectors from 21 countries, followed by a consensus meeting. Members of the CONSORT Group were involved during the development process.The paper presents the ACE checklists for AD randomised trial reports and abstracts, as well as an explanation with examples to aid the application of the guideline. The ACE checklist comprises seven new items, nine modified items, six unchanged items for which additional explanatory text clarifies further considerations for ADs, and 20 unchanged items not requiring further explanatory text. The ACE abstract checklist has one new item, one modified item, one unchanged item with additional explanatory text for ADs, and 15 unchanged items not requiring further explanatory text.The intention is to enhance transparency and improve reporting of AD randomised trials to improve the interpretability of their results and reproducibility of their methods, results and inference. We also hope indirectly to facilitate the much-needed knowledge transfer of innovative trial designs to maximise their potential benefits.

Effect of Adding Docetaxel to Androgen-Deprivation Therapy in Patients With High-Risk Prostate Cancer With Rising Prostate-Specific Antigen Levels After Primary Local Therapy: A Randomized Clinical Trial

Importance

Androgen-deprivation therapy (ADT) plus docetaxel is the standard of care in hormone-naive metastatic prostate cancer but is of uncertain benefit in a nonmetastatic, high-risk prostate cancer setting.

Objective

To assess the benefit of ADT plus docetaxel in patients presenting with rising prostate-specific antigen (PSA) levels after primary local therapy and high-risk factors but no evidence of metastatic disease.

Design, Setting, and Participants

This open-label, phase 3, randomized superiority trial comparing ADT plus docetaxel vs ADT alone enrolled patients from 28 centers in France between June 4, 2003, and September 25, 2007; final follow-up was conducted April 12, 2017, and analysis was performed May 2 to July 31, 2017. Patients had undergone primary local therapy for prostate cancer, were experiencing rising PSA levels, and were considered to be at high risk of metastatic disease. Stratification was by prior local therapy and PSA-level doubling time (≤6 vs >6 months), and intention-to-treat analysis was used.

Interventions

Patients were randomly assigned to receive ADT (1 year) plus docetaxel, 70 mg/m2 (every 3 weeks [6 cycles]), or ADT alone (1 year).

Main Outcomes and Measures

The primary outcome was PSA progression-free survival (PSA-PFS). Secondary end points were PSA response, radiologic PFS, overall survival, safety, and quality of life.

Results

Overall, 254 patients were randomized (1:1) to the trial; median age, 64 years in the ADT plus docetaxel arm, 66 years in the ADT alone arm. At a median follow-up of 30.0 months, the median PSA-PFS was 20.3 (95% CI, 19.0-21.6) months in the ADT plus docetaxel arm vs 19.3 (95% CI, 18.2-20.8) months in the ADT alone arm (hazard ratio [HR], 0.85; 95% CI, 0.62-1.16; P = .31). At a median follow-up of 10.5 years, there was no significant between-arm difference in radiologic PFS (HR, 1.03; 95% CI, 0.74-1.43; P = .88). Overall survival data were not mature. The most common grade 3 or 4 hematologic toxic effects in the ADT plus docetaxel arm were neutropenia (60 of 125 patients [48.0%]), febrile neutropenia (10 [8.0%]), and thrombocytopenia (4 [3.0%]). There was no significant between-arm difference in overall quality of life.

Conclusions and Relevance

Compared with ADT alone, combined ADT plus docetaxel therapy with curative intent did not significantly improve PSA-PFS in patients with high-risk prostate cancer and rising PSA levels and no evidence of metastatic disease.

Trial Registration

French Health Products Safety Agency identifier: 030591; ClinicalTrials.gov identifier: NCT00764166.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Reporting of master protocols towards a standardized approach: A systematic review

BACKGROUND

In September 2018 the FDA provided a draft guidance on master protocols reflecting an increased interest in these designs by industry. Master protocols refer to a single overarching protocol developed to evaluate multiple hypotheses and may be further categorized as basket, umbrella, and platform trials. However, inconsistencies in reporting persist in the literature. We conducted a systematic review to describe master protocol reporting with the goal of facilitating the further development and spread of these innovative trial designs.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL from inception to April 25, 2019 for English articles on master protocols. This was supplemented by hand searches of trial registries and of the bibliographies of published reviews. We used the FDA's definitions of master protocols as references and compared them to self-reported master protocols.

RESULTS

We identified 278 master protocol publications, consisting of 228 protocols and 50 reviews. Sixty-six records provided unique definitions of master protocol types. We observed considerable heterogeneity in definitions of master protocols, and over half (54%) used oncology-specific language. The majority of self-classified master protocols (57%) were consistent with the FDA's definitions of master protocols.

CONCLUSION

The terms 'master protocol', 'basket trial', 'umbrella trial', and 'platform trial' are inconsistently described. Careful treatment of these terms and adherence to the definitions set forth by the FDA will facilitate better understanding of these trial designs and allow them to be used broadly and to their full potential in clinical research. We encourage trial methodologists to use these trial designations when applicable.

Genomic Evaluation of Multiparametric Magnetic Resonance Imaging-visible and -nonvisible Lesions in Clinically Localised Prostate Cancer

BACKGROUND

The prostate cancer (PCa) diagnostic pathway is undergoing a radical change with the introduction of multiparametric magnetic resonance imaging (mpMRI), genomic testing, and different prostate biopsy techniques. It has been proposed that these tests should be used in a sequential manner to optimise risk stratification.

OBJECTIVE

To characterise the genomic, epigenomic, and transcriptomic features of mpMRI-visible and -nonvisible PCa in clinically localised disease.

DESIGN, SETTING, AND PARTICIPANTS

Multicore analysis of fresh prostate tissue sampled immediately after radical prostatectomy was performed for intermediate- to high-risk PCa.

INTERVENTION

Low-pass whole-genome, exome, methylation, and transcriptome profiling of patient tissue cores taken from microscopically benign and cancerous areas in the same prostate. Circulating free and germline DNA was assessed from the blood of five patients.

OUTCOME MEASUREMENT AND STATISTICAL ANALYSIS

Correlations between preoperative mpMRI and genomic characteristics of tumour and benign prostate samples were assessed. Gene profiles for individual tumour cores were correlated with existing genomic classifiers currently used for prognostication.

RESULTS AND LIMITATIONS

A total of 43 prostate cores (22 tumour and 21 benign) were profiled from six whole prostate glands. Of the 22 tumour cores, 16 were tumours visible and six were tumours nonvisible on mpMRI. Intratumour genomic, epigenomic, and transcriptomic heterogeneity was found within mpMRI-visible lesions. This could potentially lead to misclassification of patients using signatures based on copy number or RNA expression. Moreover, three of the six cores obtained from mpMRI-nonvisible tumours harboured one or more genetic alterations commonly observed in metastatic castration-resistant PCa. No circulating free DNA alterations were found. Limitations include the small cohort size and lack of follow-up.

CONCLUSIONS

Our study supports the continued use of systematic prostate sampling in addition to mpMRI, as avoidance of systematic biopsies in patients with negative mpMRI may mean that clinically significant tumours harbouring genetic alterations commonly seen in metastatic PCa are missed. Furthermore, there is inconsistency in individual genomics when genomic classifiers are applied.

PATIENT SUMMARY

Our study shows that tumour heterogeneity within prostate tumours visible on multiparametric magnetic resonance imaging (mpMRI) can lead to misclassification of patients if only one core is used for genomic analysis. In addition, some cancers that were missed by mpMRI had genomic aberrations that are commonly seen in advanced metastatic prostate cancer. Avoiding biopsies in mpMRI-negative cases may mean that such potentially lethal cancers are missed.