The ALSFRS-R Summit: a global call to action on the use of the ALSFRS-R in ALS clinical trials

The Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) was developed more than 25 years ago as an instrument to monitor functional change over time in patients with ALS. It has since been revised and extended to meet the needs of high data quality in ALS trials (ALSFRS-R), however a full re-validation of the scale was not completed. Despite this, the scale has remained a primary outcome measure in clinical trials. We convened a group of clinical trialists to discuss and explore opportunities to improve the scale and propose alternative measures. In this meeting report, we present a call to action on the use of the ALSFRS-Revised scale in clinical trials, focusing on the need for (1) harmonization of the ALSFRS-R administration globally, (2) alignment on a set of recommendations for clinical trial design and statistical analysis plans (SAPs), and (3) use of additional outcome measures.

A protocol for stakeholder engagement in deliver-EE: A pragmatic randomized comparative effectiveness trial evaluating effects of meal delivery on the ability of homebound older adults to remain in the community

BACKGROUND

Few clinical trials include a detailed protocol for stakeholder engagement in the design and execution of the clinical trial. Deliver-EE is a pragmatic clinical trial to assess how different types of home-delivered meals can affect older adults' health and well-being. We present the protocol for stakeholder engagement in this national, multi-site trial and initial findings from our efforts.

METHODS

Twenty-nine participants were recruited to two stakeholder advisory panels. The "Lived Experience Perspectives" panel is defined as the clients, caregivers, and meal delivery drivers with first-hand knowledge and lived experiences with meal delivery. The "System Perspectives" panel is defined as representatives from the larger financial, clinical, regulatory, and operational environments in which meal delivery to homebound older adults operate. Together, these two groups holistically represent interested parties that coordinate the interdependent elements of meal delivery to homebound older adults in order to: 1) inform our understanding of what matters most to older adults, their families, and the larger health and social care systems; 2) provide strategies to overcome challenges conducting the study; 3) enhance dissemination and uptake of study findings; and 4) identify opportunities for future research.

RESULTS

Although stakeholder partners share a common goal of using home-delivered meals as a method to improve outcomes for homebound older adults, individuals have different goals for participating as advisors in this research.

CONCLUSIONS

Understanding what individual stakeholders hope to gain from their participation is critical in designing an effective engagement protocol and critical for meaningful and rigorous stakeholder engagement in clinical trials.

Estimating vaccine efficacy during open-label follow-up of COVID-19 vaccine trials based on population-level surveillance data

While rapid development and roll out of COVID-19 vaccines is necessary in a pandemic, the process limits the ability of clinical trials to assess longer-term vaccine efficacy. We leveraged COVID-19 surveillance data in the U.S. to evaluate vaccine efficacy in U.S. Government-funded COVID-19 vaccine efficacy trials with a three-step estimation process. First, we used a compartmental epidemiological model informed by county-level surveillance data, a "population model", to estimate SARS-CoV-2 incidence among the unvaccinated. Second, a "cohort model" was used to adjust the population SARS-CoV-2 incidence to the vaccine trial cohort, taking into account individual participant characteristics and the difference between SARS-CoV-2 infection and COVID-19 disease. Third, we fit a regression model estimating the offset between the cohort-model-based COVID-19 incidence in the unvaccinated with the placebo-group COVID-19 incidence in the trial during blinded follow-up. Counterfactual placebo COVID-19 incidence was estimated during open-label follow-up by adjusting the cohort-model-based incidence rate by the estimated offset. Vaccine efficacy during open-label follow-up was estimated by contrasting the vaccine group COVID-19 incidence with the counterfactual placebo COVID-19 incidence. We documented good performance of the methodology in a simulation study. We also applied the methodology to estimate vaccine efficacy for the two-dose AZD1222 COVID-19 vaccine using data from the phase 3 U.S. trial (ClinicalTrials.gov # NCT04516746). We estimated AZD1222 vaccine efficacy of 59.1% (95% uncertainty interval (UI): 40.4%-74.3%) in April, 2021 (mean 106 days post-second dose), which reduced to 35.7% (95% UI: 15.0%-51.7%) in July, 2021 (mean 198 days post-second-dose). We developed and evaluated a methodology for estimating longer-term vaccine efficacy. This methodology could be applied to estimating counterfactual placebo incidence for future placebo-controlled vaccine efficacy trials of emerging pathogens with early termination of blinded follow-up, to active-controlled or uncontrolled COVID-19 vaccine efficacy trials, and to other clinical endpoints influenced by vaccination.

Tumor-agnostic baskets to N-of-1 platform trials and real-world data: Transforming precision oncology clinical trial design

Choosing the right drug(s) for the right patient via advanced genomic sequencing and multi-omic interrogation is the sine qua non of precision cancer medicine. Traditional cancer clinical trial designs follow well-defined protocols to evaluate the efficacy of new therapies in patient groups, usually identified by their histology/tissue of origin of their malignancy. In contrast, precision medicine seeks to optimize benefit in individual patients, i.e., to define who benefits rather than determine whether the overall group benefits. Since cancer is a disease driven by molecular alterations, innovative trial designs, including biomarker-defined tumor-agnostic basket trials, are driving ground-breaking regulatory approvals and deployment of gene- and immune-targeted drugs. Molecular interrogation further reveals the disruptive reality that advanced cancers are extraordinarily complex and individually distinct. Therefore, optimized treatment often requires drug combinations and N-of-1 customization, addressed by a new generation of N-of-1 trials. Real-world data and structured master registry trials are also providing massive datasets that are further fueling a transformation in oncology. Finally, machine learning is facilitating rapid discovery, and it is plausible that high-throughput computing, in silico modeling, and 3-dimensional printing may be exploitable in the near future to discover and design customized drugs in real time.

Quantifying Site Burden to Optimize Protocol Performance

BACKGROUND

The increase in protocol complexity and the resulting rise in the effort required by investigative sites to implement protocols have been well documented, but existing measures of site burden only offer an incomplete view of the burden experienced by site personnel. The introduction of Decentralized Clinical Trials-trials supported by remote and virtual technologies and services-is expected to impact the burden imposed on sites, but this impact has not yet been systematically measured.

METHODS

The Tufts Center for the Study of Drug Development conducted an online survey among clinical research sites worldwide and gathered 355 responses assessing the burden associated with distinct activities and procedures related to the implementation of clinical trial protocols using traditional and decentralized approaches.

RESULTS

A high percentage of investigative sites (50.5%) have had no experience with DCT solutions and only a small percentage (6.6%) have participated in fully decentralized clinical trials. Overall, half of respondents view DCT solutions as more burdensome than traditional clinical trials. In general, activities related to operational and managerial aspects of trial implementation were viewed as less burdensome when done remotely, while clinical procedures or elements that require study team-patient interactions were viewed as more burdensome when using DCT approaches versus in-person or traditional methods.

Hitting the Target: Developing High-quality Evidence for Proton Beam Therapy Through Randomised Controlled Trials

The National Health Service strategy for the delivery of proton beam therapy (PBT) in the UK provides a unique opportunity to deliver high-quality evidence for PBT through randomised controlled trials (RCTs). We present a summary of three UK PBT RCTs in progress, including consideration of their key design characteristics and outcome assessments, to inform and support future PBT trial development. The first three UK multicentre phase III PBT RCTs (TORPEdO, PARABLE and APPROACH), will compare PBT with photon radiotherapy for oropharyngeal squamous cell carcinoma, breast cancer and oligodendroglioma, respectively. All three studies were designed by multidisciplinary teams, which combined expertise from clinicians, clinical trialists and scientists with strong patient advocacy and guidance from national radiotherapy research networks and international collaborators. Consistent across all three studies is a focus on the reduction of long-term radiotherapy-related toxicities and an evaluation of patient-reported outcomes and health-related quality of life, which will address key uncertainties regarding the clinical benefits of PBT. Innovative translational components will provide insights into mechanisms of toxicity and help to frame the key future research questions regarding PBT. The UK radiotherapy research community is developing and delivering an internationally impactful PBT research portfolio. The combination of data from RCTs with prospectively collected data from a national PBT outcomes registry will provide an innovative, high-quality repository for PBT research and the platform to design and deliver future trials of PBT.

midazolam for rapid risk-reduction in suicidal, depressed emergency patients: Clinical trial design and rationale

Emergency department (ED) visits for suicidal ideation or behavior have been increasing in all age groups, particularly younger adults. A rapid-acting treatment to reduce suicidal thinking, adapted for ED use, is needed. Previous studies have shown a single dose of ketamine can improve depression and suicidal ideation within hours. However, most studies used 40 min intravenous infusions which can be impractical in a psychiatric ED. The ER-Ketamine study we describe here is a randomized midazolam-controlled clinical trial (RCT; NCT04640636) testing intramuscular (IM) ketamine's feasibility, safety, and effectiveness to rapidly reduce suicidal ideation and depression in a psychiatric ED. A pre-injection phase involves screening, informed consent, eligibility confirmation, and baseline assessment of suicidal ideation, depression, and comorbidities. The randomized double-blind IM injection is administered in the ED under research staff supervision, vital sign monitoring, pharmacokinetic blood sampling, and clinical assessments. The post-injection phase occurs on a psychiatric inpatient unit with follow-up research assessments through four weeks post-discharge. Outcome measures are feasibility, safety, and effects on suicidal ideation and depression at 24 h post-injection, and through follow-up. The target sample is N = 90 adults in a major depressive episode, assessed by ED clinicians as warranting hospitalization for suicide risk. Here we report design, rationale, and preliminary feasibility and safety for this ongoing study. Demographics of the 53 participants (ages 18 to 65 years) randomized to date suggest a diverse sample tending towards younger adults.

The staircase cluster randomised trial design: A pragmatic alternative to the stepped wedge

This article introduces the 'staircase' design, derived from the zigzag pattern of steps along the diagonal of a stepped wedge design schematic where clusters switch from control to intervention conditions. Unlike a complete stepped wedge design where all participating clusters must collect and provide data for the entire trial duration, clusters in a staircase design are only required to be involved and collect data for a limited number of pre- and post-switch periods. This could alleviate some of the burden on participating clusters, encouraging involvement in the trial and reducing the likelihood of attrition. Staircase designs are already being implemented, although in the absence of a dedicated methodology, approaches to sample size and power calculations have been inconsistent. We provide expressions for the variance of the treatment effect estimator when a linear mixed model for an outcome is assumed for the analysis of staircase designs in order to enable appropriate sample size and power calculations. These include explicit variance expressions for basic staircase designs with one pre- and one post-switch measurement period. We show how the variance of the treatment effect estimator is related to key design parameters and demonstrate power calculations for examples based on a real trial.

Optimal trial design selection: a comparative analysis between two-arm and three-arm trials incorporating network meta-analysis for evaluating a new treatment

BACKGROUND

Planning the design of a new trial comparing two treatments already in a network of trials with an a-priori plan to estimate the effect size using a network meta-analysis increases power or reduces the sample size requirements. However, when the comparison of interest is between a treatment already in the existing network (old treatment) and a treatment that hasn't been studied previously (new treatment), the impact of leveraging information from the existing network to inform trial design has not been extensively investigated. We aim to identify the most powerful trial design for a comparison of interest between an old treatment A and a new treatment Z, given a fixed total sample size. We consider three possible designs: a two-arm trial between A and Z ('direct two-arm'), a two-arm trial between another old treatment B and Z ('indirect two-arm'), and a three-arm trial among A, B, and Z.

METHODS

We compare the standard error of the estimated effect size between treatments A and Z for each of the three trial designs using formulas. For continuous outcomes, the direct two-arm trial always has the largest power, while for a binary outcome, the minimum variances among the three trial designs are conclusive only when [Formula: see text]. Simulation studies are conducted to demonstrate the potential for the indirect two-arm and three-arm trials to outperform the direct two-arm trial in terms of power under the condition of [Formula: see text].

RESULTS

Based on the simulation results, we observe that the indirect two-arm and three-arm trials have the potential to be more powerful than a direct two-arm trial only when [Formula: see text]. This power advantage is influenced by various factors, including the risk of the three treatments, the total sample size, and the standard error of the estimated effect size from the existing network meta-analysis.

CONCLUSIONS

The standard two-arm trial design between two treatments in the comparison of interest may not always be the most powerful design. Utilizing information from the existing network meta-analysis, incorporating an additional old treatment into the trial design through an indirect two-arm trial or a three-arm trial can increase power.

Novel 3-arm wait-list controlled trial designs together with mixed-effects analysis improve precision of treatment effect estimators

Clinical trialists have long been searching for approaches to increase statistical power without increasing sample size. Conventional wait-list controlled (WLC) trials are limited to two trial arms and two or three repeated measurements per person. These features limit statistical power. Furthermore, their analysis is usually based on analysis of covariance or mixed effects modelling, with a focus on estimating treatment effect at one time-period after initiation of therapy. We propose two 3-arm WLC trial designs together with a mixed-effects analysis framework. The designs require three or four repeated measurements per person. The analytic framework defines up to three treatment effect estimands, representing the effects at one to three time-periods after initiation of therapy. The precision (inverse of variance) of the treatment effect estimators in the new and conventional trial designs are analytically derived and evaluated in simulations. The results are interpreted in the context of a cognitive training trial in older people. The proposed designs and analysis methods increase the precision level of treatment effect estimators as compared to conventional designs and analyses. Given a target level of statistical power, the proposed methods require a smaller number of participants per trial than the conventional methods, without necessarily increasing the number of measurements per trial. Furthermore, the proposed analytic framework sheds light on the treatment effects at different times after initiation of therapy, which is not usually considered in conventional WLC trial analysis. In situations that a WLC trial is appropriate, the 3-arm designs are useful alternatives to existing 2-arm designs.

Longitudinal resting-state EEG in amyloid-positive patients along the Alzheimer's disease continuum: considerations for clinical trials

BACKGROUND

To enable successful inclusion of electroencephalography (EEG) outcome measures in Alzheimer's disease (AD) clinical trials, we retrospectively mapped the progression of resting-state EEG measures over time in amyloid-positive patients with mild cognitive impairment (MCI) or dementia due to AD.

METHODS

Resting-state 21-channel EEG was recorded in 148 amyloid-positive AD patients (MCI, n = 88; dementia due to AD, n = 60). Two or more EEG recordings were available for all subjects. We computed whole-brain and regional relative power (i.e., theta (4-8 Hz), alpha1 (8-10 Hz), alpha2 (10-13 Hz), beta (13-30 Hz)), peak frequency, signal variability (i.e., theta permutation entropy), and functional connectivity values (i.e., alpha and beta corrected amplitude envelope correlation, theta phase lag index, weighted symbolic mutual information, inverted joint permutation entropy). Whole-group linear mixed effects models were used to model the development of EEG measures over time. Group-wise analysis was performed to investigate potential differences in change trajectories between the MCI and dementia subgroups. Finally, we estimated the minimum sample size required to detect different treatment effects (i.e., 50% less deterioration, stabilization, or 50% improvement) on the development of EEG measures over time, in hypothetical clinical trials of 1- or 2-year duration.

RESULTS

Whole-group analysis revealed significant regional and global oscillatory slowing over time (i.e., increased relative theta power, decreased beta power), with strongest effects for temporal and parieto-occipital regions. Disease severity at baseline influenced the EEG measures' rates of change, with fastest deterioration reported in MCI patients. Only AD dementia patients displayed a significant decrease of the parieto-occipital peak frequency and theta signal variability over time. We estimate that 2-year trials, focusing on amyloid-positive MCI patients, require 36 subjects per arm (2 arms, 1:1 randomization, 80% power) to detect a stabilizing treatment effect on temporal relative theta power.

CONCLUSIONS

Resting-state EEG measures could facilitate early detection of treatment effects on neuronal function in AD patients. Their sensitivity depends on the region-of-interest and disease severity of the study population. Conventional spectral measures, particularly recorded from temporal regions, present sensitive AD treatment monitoring markers.

Community-based management of a five-arm randomised clinical trial in COVID-19 outpatients in South Africa: challenges and opportunities

BACKGROUND

Repeated COVID-19 waves and corresponding mitigation measures have impacted health systems globally with exceptional challenges. In response to the pandemic, researchers, regulators, and funders rapidly pivoted to COVID-19 research activities. However, many clinical drug studies were not completed, due to often complex and rapidly evolving research conditions.

METHODS

We outline our experience of planning and managing a randomised, adaptive, open-label, phase 2 clinical trial to evaluate the safety and efficacy of four repurposed drug regimens versus standard-of-care (SOC) in outpatients with 'mild to moderate' COVID-19 in Johannesburg, South Africa, in the context of a partnership with multiple stakeholders. The study was conducted between 3 September 2020 and 23 August 2021 during changing COVID-19 restrictions, significant morbidity and mortality waves, and allied supply line, economic, and political instability.

RESULTS

Our clinical study design was pragmatic, including low-risk patients who were treated open label. There was built-in flexibility, including provision for some sample size adjustment and a range of secondary efficacy outcomes. Barriers to recruitment included the timing of waves, staff shortages due to illness, late presentation of patients, COVID-19 misinformation, and political unrest. Mitigations were the use of community health workers, deployment of mobile clinical units, and simplification of screening. Trial management required a radical reorganisation of logistics and processes to accommodate COVID-19 restrictions. These included the delivery of staff training and monitoring remotely, electronic consent, patient training and support to collect samples and report data at home, and the introduction of tele-medicine. These measures were successful for data collection, safe, and well received by patients.

CONCLUSION

Completing a COVID-19 trial in outpatients during the height of the pandemic required multiple innovations in nearly every aspect of clinical trial management, a high commitment level from study staff and patients, and support from study sponsors. Our experience has generated a more robust clinical research infrastructure, building in efficiencies to clinical trial management beyond the pandemic.

Reflections from the OARSI 2022 clinical trials symposium: The pain of OA-Deconstruction of pain and patient-reported outcome measures for the benefit of patients and clinical trial design

OBJECTIVE

Osteoarthritis (OA) drug development is hampered by a number of challenges. One of the main challenges is the apparent discordance between pain and structure, which has had a significant impact on drug development programs and has led to hesitance among stakeholders. Since 2017, the Clinical Trials Symposium (CTS) has been hosted under the Osteoarthritis Research Society International (OARSI) leadership. OARSI and the CTS steering committee yearly invite and encourage discussions on selected special subject matter between regulators, drug developers, clinicians, clinical researchers, biomarker specialists, and basic scientists to progress drug development in the OA field.

METHOD

The main topic for the 2022 OARSI CTS was to elucidate the many facets of pain in OA and to enable a discussion between regulators (Food and Drug Administration (FDA) and the European Medicines Agency (EMA)) and drug developers to clarify outcomes and study designs for OA drug development.

RESULTS

Signs or symptoms indicative of nociceptive pain occur in 50-70% of OA patients, neuropathic-like pain in 15-30% of patients, and nociplastic pain in 15-50% of patients. Weight-bearing knee pain is associated with bone marrow lesions and effusions. There are currently no simple objective functional tests whose improvements correlate with patient perceptions.

CONCLUSIONS

The CTS participants, in collaboration with the FDA and EMA, raised several suggestions that they consider key to future clinical trials in OA including the need for more precise differentiation of pain symptoms and mechanisms, and methods to reduce placebo responses in OA trials.

Design and analysis considerations for early phase clinical trials in hepatitis B (HBV) cure research: the ACTG A5394 study in persons with both HIV and HBV

With growing interest and efforts to achieve a hepatitis B (HBV) cure, HBV therapeutics have increasingly entered the clinical testing phase. In designing an early phase clinical trial aimed at HBV cure, the heterogeneity in participants and the choice of a biomarker endpoint that signals a cure requires careful consideration. We describe the key elements to consider during the development of HBV clinical trials aimed at a functional cure, and how we have addressed them in the design of a phase II AIDS Clinical Trials Group (ACTG) study, A5394 (NCT05551273). The trial we present is for persons with both HIV and HBV, a unique population that has much to gain from an HBV cure. Our decisions on the design elements are specific to the study agent and the targeted population, but our deliberations may be informative in the emerging field of early phase HBV trials aimed at cure.

Challenges and strategies for clinical trials in propionic and methylmalonic acidemias

Clinical trial development in rare diseases poses significant study design and methodology challenges, such as disease heterogeneity and appropriate patient selection, identification and selection of key endpoints, decisions on study duration, choice of control groups, selection of appropriate statistical analyses, and patient recruitment. Therapeutic development in organic acidemias (OAs) shares many challenges with other inborn errors of metabolism, such as incomplete understanding of natural history, heterogenous disease presentations, requirement for sensitive outcome measures and difficulties recruiting a small sample of participants. Here, we review strategies for the successful development of a clinical trial to evaluate treatment response in propionic and methylmalonic acidemias. Specifically, we discuss crucial decisions that may significantly impact success of the study, including patient selection, identification and selection of endpoints, determination of the study duration, consideration of control groups including natural history controls, and selection of appropriate statistical analyses. The significant challenges associated with designing a clinical trial in rare disease can sometimes be successfully met through strategic engagement with experts in the rare disease, seeking regulatory and biostatistical guidance, and early involvement of patients and families.

Why do we not have more drugs approved for MDS? A critical viewpoint on novel drug development in MDS

Approval of new agents to treat higher risk (HR) myelodysplastic syndrome (MDS) has stalled since the approval of DNA methyltransferase inhibitors (DNMTi). In addition, the options for patients with lower risk (LR) MDS who have high transfusion needs and do not harbor ring sideroblasts or 5q- syndrome are limited. Here, we review the current treatment landscape in MDS and identify areas of unmet need, such as treatment after failure of erythropoiesis-stimulating agents or DNMTis, TP53-mutated disease, and MDS with potentially targetable mutations. We discuss how our understanding of MDS pathogenesis can inform therapy development, including treating HR-MDS similarly to AML and pursuing therapies to address splicing factor mutations and dysregulated inflammation. We then bring a critical lens to current methodology of MDS studies and propose solutions to improve the efficiency and yield of these clinical trials, including using the most meaningful response metrics and expanding enrollment.

Looking ahead in early-phase trial design to improve the drug development process: examples in oncology

BACKGROUND

Clinical trial design must consider the specific resource constraints and overall goals of the drug development process (DDP); for example, in designing a phase I trial to evaluate the safety of a drug and recommend a dose for a subsequent phase II trial. Here, we focus on design considerations that involve the sequence of clinical trials, from early phase I to late phase III, that constitute the DDP.

METHODS

We discuss how stylized simulation models of clinical trials in an oncology DDP can quantify important relationships between early-phase trial designs and their consequences for the remaining phases of development. Simulations for three illustrative settings are presented, using stylized models of the DDP that mimic trial designs and decisions, such as the potential discontinuation of the DDP.

RESULTS

We describe: (1) the relationship between a phase II single-arm trial sample size and the likelihood of a positive result in a subsequent phase III confirmatory trial; (2) the impact of a phase I dose-finding design on the likelihood that the DDP will produce evidence of a safe and effective therapy; and (3) the impact of a phase II enrichment trial design on the operating characteristics of a subsequent phase III confirmatory trial.

CONCLUSIONS

Stylized models of the DDP can support key decisions, such as the sample size, in the design of early-phase trials. Simulation models can be used to estimate performance metrics of the DDP under realistic scenarios; for example, the duration and the total number of patients enrolled. These estimates complement the evaluation of the operating characteristics of early-phase trial design, such as power or accuracy in selecting safe and effective dose levels.

Optimizing the Design of Clinical Trials to Evaluate the Efficacy of Function-Promoting Therapies

BACKGROUND

Several candidate molecules that may have application in treating physical limitations associated with aging and chronic diseases are in development. Challenges in the framing of indications, eligibility criteria, and endpoints and the lack of regulatory guidance have hindered the development of function-promoting therapies.

METHODS

Experts from academia, pharmaceutical industry, National Institutes of Health (NIH), and Food and Drug Administration (FDA) discussed optimization of trial design including the framing of indications, eligibility criteria, and endpoints.

RESULTS

Mobility disability associated with aging and chronic diseases is an attractive indication because it is recognized by geriatricians as a common condition associated with adverse outcomes, and it can be ascertained reliably. Other conditions associated with functional limitation in older adults include hospitalization for acute illnesses, cancer cachexia, and fall injuries. Efforts are underway to harmonize definitions of sarcopenia and frailty. Eligibility criteria should reconcile the goals of selecting participants with the condition and ensuring generalizability and ease of recruitment. An accurate measure of muscle mass (eg, D3 creatine dilution) could be a good biomarker in early-phase trials. Performance-based and patient-reported measures of physical function are needed to demonstrate whether treatment improves how a person lives, functions, or feels. Multicomponent functional training that integrates training in balance, stability, strength, and functional tasks with cognitive and behavioral strategies may be needed to translate drug-induced muscle mass gains into functional improvements.

CONCLUSIONS

Collaborations among academic investigators, NIH, FDA, pharmaceutical industry, patients, and professional societies are needed to conduct well-designed trials of function-promoting pharmacological agents with and without multicomponent functional training.

Covariate-constrained randomization with cluster selection and substitution

BACKGROUND

An ongoing cluster-randomized trial for the prevention of arboviral diseases utilizes covariate-constrained randomization to balance two treatment arms across four specified covariates and geographic sector. Each cluster is within a census tract of the city of Mérida, Mexico, and there were 133 eligible tracts from which to select 50. As some selected clusters may have been subsequently found unsuitable in the field, we desired a strategy to substitute new clusters while maintaining covariate balance.

METHODS

We developed an algorithm that successfully identified a subset of clusters that maximized the average minimum pairwise distance between clusters in order to reduce contamination and balanced the specified covariates both before and after substitutions were made.

SIMULATIONS

Simulations were performed to explore some limitations of this algorithm. The number of selected clusters and eligible clusters were varied along with the method of selecting the final allocation pattern.

CONCLUSION

The algorithm is presented here as a series of optional steps that can be added to the standard covariate-constrained randomization process in order to achieve spatial dispersion, cluster subsampling, and cluster substitution. Simulation results indicate that these extensions can be used without loss of statistical validity, given a sufficient number of clusters included in the trial.

Designing and conducting a clinical trial in blood and marrow transplantation

Clinical trials form the cornerstone of the science-based approach to improving patient outcomes. A trial needs to be designed and performed carefully to provide valid evidence to inform medical science and to protect the safety and well-being of its participants. The development of a clinical trial involving blood and marrow transplant (BMT) requires special considerations, including the rare disease populations involved and transplant-specific outcomes of interest that necessitate appropriate analysis techniques to evaluate. This article reviews key considerations and best practices for the design and conduct of a clinical trial in BMT, including the selection of patient population, treatment groups, objectives and endpoints, targeted sample size, statistical analysis strategy, provisions for monitoring patient safety and trial progress, and dissemination of trial results. The practical application of these principles is demonstrated using BMT CTN 1301, a recently completed clinical trial evaluating regimens for chronic graft-versus-host disease prevention in transplant patients.

Systematic analysis of randomised controlled trials of Chinese herb medicine for non-alcoholic steatohepatitis (NASH): implications for future drug development and trial design

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is a liver disease currently lacking an approved therapy, resulting in significant clinical demand. Traditional Chinese medicines (TCMs) have been commonly used to manage NASH. This study aimed to systematically analyse the randomised controlled trials (RCTs) using TCMs for NASH management.

METHODS

A systematic literature review was performed by following PRISMA guidelines 2020 in six electronic databases: PubMed, Web of Science, Scopus, Embase, the Cochrane Library, and China National Knowledge Infrastructure, from inception until August 2022. RCTs using TCMs for NASH were included in the analysis, irrespective of language or blinding.

RESULTS

112 RCTs were included in this review, with 10,573 NASH participants. 108 RCTs were conducted in China, and 4 RCTs were in other countries. Herbal medicine decoction was the major dosage form used for treating NASH (82/112). 11 TCMs products have been approved for NASH treatment (8 in China, 2 in Iran, and 1 in Japan). Classic prescriptions, such as "Huang Lian Jie Du decoction", "Yin Chen Hao decoction", and "Yi Guan Jian" were used in some studies. The TCMs treatment of NASH involved the use of 199 different plants, with the top 5 herbs being Salviae Miltiorrhizae Radix Et Rhizoma, Alismatis Rhizoma, Bupleuri Radix, Poria, and Curcumae Radix. "Salviae Miltiorrhizae Radix Et Rhizoma + Bupleuri Radix/Alismatis Rhizoma" were the mostly common drug-pair in the herbs network analysis. Nowadays, "Bupleuri Radix/Alismatis Rhizoma + Atractylodis Macrocephalae Rhizoma" are increasingly applied in herbal formulas for NASH. Based on the PICOS principles, the included studies varied in terms of the population, intervention, comparator, outcomes, and study design. However, some studies reported unstandardised results and failed to report diagnostic standards, inclusion or exclusion criteria, or sufficient patient information.

CONCLUSION

Adopting Chinese classic prescriptions or drug-pair may provide a basis for developing new drugs of NASH management. Further research is needed to refine the clinical trial design and obtain more convincing evidence for using TCMs to treat NASH.

Connecting a disconnected trial network with a new trial: optimizing the estimation of a comparative effect in a network meta-analysis

BACKGROUND

In network meta-analysis, estimation of a comparative effect can be performed for treatments that are connected either directly or indirectly. However, disconnected trial networks may arise, which poses a challenge to comparing all available treatments of interest. Several modeling approaches attempt to compare treatments from disconnected networks but not without strong assumptions and limitations. Conducting a new trial to connect a disconnected network can enable calculation of all treatment comparisons and help researchers maximize the value of the existing networks. Here, we develop an approach to finding the best connecting trial given a specific comparison of interest.

METHODS

We present formulas to quantify the variation in the estimation of a particular comparative effect of interest for any possible connecting two-arm trial. We propose a procedure to identify the optimal connecting trial that minimizes this variation in effect estimation.

RESULTS

We show that connecting two treatments indirectly might be preferred to direct connection through a new trial, by leveraging information from the existing disconnected networks. Using a real network of studies on the use of vaccines in the treatment of bovine respiratory disease (BRD), we illustrate a procedure to identify the best connecting trial and confirm our findings via simulation.

CONCLUSION

Researchers wishing to conduct a connecting two-arm study can use the procedure provided here to identify the best connecting trial. The choice of trial that minimizes the variance of a comparison of interest is network dependent and it is possible that connecting treatments indirectly may be preferred to direct connection.

The dilemma between milestones of progression versus clinical scales in Parkinson's disease

There are significant challenges in accurately documenting the progression of Parkinson's disease (PD). The disease course is highly heterogeneous, there are no validated biomarkers, and we are reliant on repeated clinical measures to assess disease state over time. Yet, the ability to chart disease progression accurately is vital in both observational and interventional study designs, where reliable measures are critical to determine whether an outcome has been met. In this chapter, we first discuss the natural history of PD, including the spectrum of clinical presentation and expected developments through the course of the disease. We then explore in detail the current strategies for measuring disease progression, which can be broadly divided into: (i) the use of quantitative clinical scales; and (ii) determination of the onset time of key milestones. We discuss the strengths and limitations of these approaches for use in clinical trials, with a particular focus on disease modification trials. The selection of outcome measures for a particular study will depend on multiple factors, but trial duration is an important determinant. Milestones are reached over a course of years rather than months, and hence clinical scales with sensitivity to change are needed for short-term studies. However, milestones represent important markers of disease stage which are not confounded by symptomatic therapies and are of critical relevance to the patient. Prolonged but low intensity follow-up beyond a limited period of treatment with a putative disease-modifying agent may allow milestones to be incorporated into evaluation of efficacy in a practical and cost-effective way.

Design, rationale, and baseline characteristics of a randomized controlled trial evaluating a mobile relational agent to enhance atrial fibrillation self-care

Atrial fibrillation (AF) is a chronic cardiovascular disease that frequently causes disruptive symptoms, adverse outcomes, and poor health-related quality of life (HRQoL). We have developed a mobile health application for individuals with AF which provides a longitudinal, patient-centered program to improve self-care. The defining feature of the application is the use of a relational agent, which uses synthetic speech accompanied by animation to provide health education, empathic counseling, and monitoring. In the present manuscript we present the design, rationale, and baseline characteristics of participants enrolled in "A Mobile Relational Agent to Enhance Atrial Fibrillation Self-Care Trial," a randomized trial testing the effectiveness the application for urban-dwelling individuals with AF being treated with oral anticoagulation for prevention of thromboembolic ischemic stroke. This is a single-center, parallel-arm randomized trial that assigned patients to the novel application (relational agent) versus a control intervention (WebMD). This ongoing RCT aims to determine the effect of the mobile health application on: (1) anticoagulation adherence; (2) patient-centered outcomes (quality of life and symptoms); and (3) health care utilization. The primary outcome, anticoagulation adherence, will be measured using the proportion of days covered (PDC). The study completed enrollment on April 1, 2022 (final enrollment n = 243 participants) with expected completion date of April 2023. (http://clinicaltrials.gov registration NCT04075994).

How do study design features and participant characteristics influence willingness to participate in clinical trials? Results from a choice experiment

BACKGROUND

Research about the decision to participate in a clinical study has tended to be limited to single indications and has focused on narrow sets of study and participant characteristics. This study applied stated preference methods to understand the clinical trial design attributes that most influence willingness to participate and how this varied with participant characteristics.

METHODS

Adults residing in the US, China, or Poland with a self-reported diagnosis of cancer, heart disease, migraine, rheumatoid arthritis, or multiple sclerosis completed an online survey. Participants were asked whether they would participate in clinical studies defined by seventeen attributes within five categories (payment/support, administration/procedures, treatment-related, study location/time commitment, and data collection/feedback). Participants saw six different hypothetical clinical study profiles. Depending on their participation decision to an initial clinical study profile, the subsequent five questions had one design attribute (randomly selected per question) consecutively improved or deteriorated to elicit preferences. A logistic regression was used to determine which participant characteristics influenced participation decisions. A latent class logit model was used to identify how the influence of study design features varied between participants and whether groups of participants with similar preferences could be identified.

RESULTS

The survey was completed by 487 participants (32% China, 35% Poland, 33% US; 8%-19% per indication). Willingness to participate was found to be a function of participant age, certain elements of quality of life, and previous treatment experience, in particular number of lines of treatment received and experience of adverse events. Willingness to participate was influenced by study design features such as payment, study duration, and time commitment - both the overall time and whether the time was at home or away from home, with the latter being particularly relevant to participants experiencing fatigue due to their disease.

CONCLUSIONS

This study quantifies how study designs influence willingness to participate and how this varies with participant types. These findings suggest that it is how an indication influences quality of life and treatment experience, rather than the indication alone, that impacts participation rates, opening the way for insights that are transferrable across indications, which may be particularly useful when considering rare diseases.

Antibody drug conjugates: The dos and don'ts in clinical development

Antibody Drug Conjugates (ADCs) entered clinical trials in the mid 1990s to selectively deliver cytotoxic chemotherapy to cancer cells with the goal to increase the antitumor activity and decrease normal tissue toxicity. Over nearly 30 years of development the ADC platform has become established with now 11 approved agents and many more in the pipeline. This review is designed to highlight some of the problems and solutions encountered in clinical development as well as provide practical instruction to both clinical investigators on the efficient protocol design for ADCs and the lessons learned.

Using information from network meta-analyses to optimize the power and sample allocation of a subsequent trial with a new treatment

BACKGROUND

A critical step in trial design is determining the sample size and sample allocation to ensure the proposed study has sufficient power to test the hypothesis of interest: superiority, equivalence, or non-inferiority. When data are available from prior trials and leveraged with the new trial to answer the scientific questions, the value of society's investment in prior research is increased. When prior information is available, the trial design including the sample size and allocation should be adapted accordingly, yet the current approach to trial design does not utilize such information. Ensuring we maximize the value of prior research is essential as there are always constraints on resources, either physical or financial, and designing a trial with adequate power can be a challenge.

METHODS

We propose an approach to increasing the power of a new trial by incorporating evidence from a network meta-analysis into the new trial design and analysis. We illustrate the methodology through an example network meta-analysis, where the goal is to identify the optimal allocation ratio for the new three-arm trial, which involves the reference treatment, the new treatment, and the negative control. The primary goal of the new trial is to show that the new treatment is non-inferior to the reference treatment. It may also be of interest to know if the new treatment is superior to the negative control. We propose an optimal treatment allocation strategy which is derived from minimizing the standard error of the log odds ratio estimate of the comparison of interest. We conducted a simulation study to assess the proposed methods to design a new trial while borrowing information from the existing network meta-analysis and compare it to even allocation methods.

RESULTS

Using mathematical derivation and simulations, we document that our proposed approach can borrow information from a network meta-analysis to modify the treatment allocation ratio and increase the power of the new trial given a fixed total sample size or to reduce the total sample size needed to reach a desired power.

CONCLUSIONS

When prior evidence about the hypotheses of interest is available, the traditional equal allocation strategy is not the most powerful approach anymore. Our proposed methodology can improve the power of trial design, reduce the cost of trials, and maximize the utility of prior investments in research.

Emulation of the control cohort of a randomized controlled trial in pediatric kidney transplantation with Real-World Data from the CERTAIN Registry

BACKGROUND

Randomized controlled trials in pediatric kidney transplantation are hampered by low incidence and prevalence of kidney failure in children. Real-World Data from patient registries could facilitate the conduct of clinical trials by substituting a control cohort. However, the emulation of a control cohort by registry data in pediatric kidney transplantation has not been investigated so far.

METHODS

In this multicenter comparative analysis, we emulated the control cohort (n = 54) of an RCT in pediatric kidney transplant patients (CRADLE trial; ClinicalTrials.gov NCT01544491) with data derived from the Cooperative European Paediatric Renal Transplant Initiative (CERTAIN) registry, using the same inclusion and exclusion criteria (CERTAIN cohort, n = 554).

RESULTS

Most baseline patient and transplant characteristics were well comparable between both cohorts. At year 1 posttransplant, a composite efficacy failure end point comprising biopsy-proven acute rejection, graft loss or death (5.8% ± 3.3% vs. 7.5% ± 1.1%, P = 0.33), and kidney function (72.5 ± 24.9 vs. 77.3 ± 24.2 mL/min/1.73 m² P = 0.19) did not differ significantly between CRADLE and CERTAIN. Furthermore, the incidence and severity of BPAR (5.6% vs. 7.8%), the degree of proteinuria (20.2 ± 13.9 vs. 30.6 ± 58.4 g/mol, P = 0.15), and the key safety parameters such as occurrence of urinary tract infections (24.1% vs. 15.5%, P = 0.10) were well comparable.

CONCLUSIONS

In conclusion, usage of Real-World Data from patient registries such as CERTAIN to emulate the control cohort of an RCT is feasible and could facilitate the conduct of clinical trials in pediatric kidney transplantation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Design of a randomized, placebo-controlled, phase 2 study evaluating the safety and efficacy of tanezumab for treatment of schwannomatosis-related pain

BACKGROUND

Schwannomatosis (SWN) is a rare tumor suppressor syndrome that predisposes affected individuals to develop multiple schwannomas and, less often, meningiomas. The most common symptom is chronic, severe pain. No medications are broadly effective in treating SWN-associated pain. The clinical trial described in this manuscript is a phase 2, randomized, double-blind, placebo-controlled study investigating the safety and efficacy of tanezumab - a humanized monoclonal antibody that inhibits nerve growth factor - for treatment of SWN-related pain. As the first therapeutic trial for SWN-related pain, it also aims to evaluate trial endpoints, understand recruitment patterns, and improve clinical trial design in this rare disease.

AIMS

The primary objective of this trial is to assess the analgesic efficacy of subcutaneous tanezumab 10 mg in subjects with SWN who continue pre-existing pain therapy (excluding non-steroidal anti-inflammatory drugs). The secondary objective is to assess safety in this population. Exploratory objectives include assessment of pain features, quality of life, and predictive biomarkers.

METHODS

The study is comprised of four periods (pre-treatment, double-blind treatment, single-arm treatment, safety follow-up) across 10 months with a delayed-start trial design to allow all participants to receive tanezumab. Forty-six participants will be enrolled and randomized 1:1 to receive either tanezumab or placebo subcutaneously in the double-blind treatment period; all participants receive tanezumab during the single-arm treatment period.

CONCLUSIONS

This study is the first therapeutic trial for SWN patients and targets a biological driver of SWN-related pain. It aims to establish a model for future pain studies in SWN and other rare diseases.

CLINICAL TRIAL REGISTRATION

NCT04163419 on ClinicalTrials.gov.

The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study: International consensus on outcome measures for trials of interventions for adults with single-sided deafness

Background

Single-sided deafness (SSD) has functional, psychological, and social consequences. Interventions for adults with SSD include hearing aids and auditory implants. Benefits and harms (outcome domains) of these interventions are until now reported inconsistently in clinical trials. Inconsistency in reporting outcome measures prevents meaningful comparisons or syntheses of trial results. The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) international initiative used structured communication techniques to achieve consensus among healthcare users and professionals working in the field of SSD. The novel contribution is a set of core outcome domains that experts agree are critically important to assess in all clinical trials of SSD interventions.

Methods

A long list of candidate outcome domains compiled from a systematic review and published qualitative data, informed the content of a two-round online Delphi survey. Overall, 308 participants from 29 countries were enrolled. Of those, 233 participants completed both rounds of the survey and scored each outcome domain on a 9-point scale. The set of core outcome domains was finalised via a web-based consensus meeting with 12 participants. Votes involved all stakeholder groups, with an approximate 2:1 ratio of professionals to healthcare users participating in the Delphi survey, and a 1:1 ratio participating in the consensus meeting.

Results

The first round of the survey listed 44 potential outcome domains, organised thematically. A further five outcome domains were included in Round 2 based on participant feedback. The structured voting at round 2 identified 17 candidate outcome domains which were voted on at the consensus meeting. Consensus was reached for a core outcome domain set including three outcome domains: spatial orientation, group conversations in noisy social situations, and impact on social situations. Seventy-seven percent of the remaining Delphi participants agreed with this core outcome domain set.

Conclusions

Adoption of the internationally agreed core outcome domain set would promote consistent assessment and reporting of outcomes that are meaningful and important to all relevant stakeholders. This consistency will in turn enable comparison of outcomes reported across clinical trials comparing SSD interventions in adults and reduce research waste. Further research will determine how those outcome domains should best be measured.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06702-1.

How can a joint European health technology assessment provide an 'additional benefit' over the current standard of national assessments? : Insights generated from a multi-stakeholder survey in hematology/oncology

OBJECTIVES

We conducted a multi-stakeholder survey to determine key areas where a joint European health technology assessment (HTA) could provide 'additional benefit' compared to the status quo of many parallel independent national and subnational assessments.

METHODS

Leveraging three iterative Delphi cycles, a semiquantitative questionnaire was developed covering evidence challenges and heterogeneity of value drivers within HTAs across Europe with a focus on hematology/oncology. The questionnaire consisted of five sections: i) background information; ii) value drivers in HTA assessments today; iii) evolving evidence challenges; iv) heterogeneity of value drivers across Europe; v) impact of Europe's Beating Cancer Plan (EBCP). The questionnaire was circulated across n = 189 stakeholder institutions comprising HTA and regulatory bodies, clinical oncology associations, patient representatives, and industry associations.

RESULTS

N = 30 responses were received (HTA bodies: 9; regulators: 10; patients' and physicians' associations: 3 each; industry: 5). Overall, 17 countries and EU level institutions were represented in the responses. Consistency across countries and stakeholder groups was high. Most relevant value drivers in HTAs today (scale 1, low to 5, high) were clinical trial design (mean 4.45), right endpoints (mean 4.40), and size of comparative effect (mean 4.33). Small patient numbers (mean 4.28) and innovative study designs (mean 4.1) were considered the most relevant evolving evidence challenges. Heterogeneity between regulatory and HTA evidence requirements and heterogeneity of the various national treatment standards and national HTA evidence requirements was high. All clinical and patient participants stated to have been with EBCP initiatives.

CONCLUSIONS

For a European HTA to provide an 'additional benefit' over the multitude of existing national assessments key methodological and process challenges need to be addressed. These include approaches to address uncertainty in clinical development; comparator choice; consistency in approaching patient-relevant endpoints; and a transparent and consistent management of both HTA and regulatory procedures as well as their interface, including all involved stakeholder groups.

The feasibility of a crossover, randomized controlled trial design to assess the effect of probiotics and prebiotics on health of elite Swiss para-athletes: a study protocol

BACKGROUND

Spinal cord injury (SCI) may cause an autonomic imbalance in the gastrointestinal tract, leading to deficits in colonic motility, mucosal secretions, vascular tone, and an increase of intestinal barrier permeability. Autonomic denervation and factors such as age, physical activity, antibiotic use and stress may cause intestinal bacterial translocation, decreased microbiota diversity, known as gut dysbiosis and thus increase susceptibility to experiencing gastrointestinal discomfort. Probiotic treatment in individuals with SCI may normalize the gut microbiota and improve overall health. We aim to assess the feasibility of probiotic and prebiotic intervention in athletes with SCI and collect information necessary for sample size calculation of a definite trial on improving health outcomes in para-athletes.

METHODS AND ANALYSIS

Elite Swiss para-athletes (aged> 18 years), being shortlisted for the Paralympic Games 2021 in Tokyo or a member of a national team (n = 43), will be invited to participate in this single-center randomized crossover trial. Athletes suffering from chronic inflammatory bowel diseases, those currently taking antibiotics or other medication to alleviate gastro-intestinal complaints will not be eligible to be included in the study. Athletes will be randomized (1:1) to receive for 4 weeks a daily dose of either 3 g of probiotic preparation or 5 g of prebiotic (organic oat bran) supplementation in addition to usual diet, followed by a 4-week washout period or vice versa. The primary outcome is the feasibility of the study, measured by recruitment and dropout rates, feasibility of the measurements, acceptability and adherence to the intervention. Secondary outcomes include gastrointestinal health assessment, diet and training information, handgrip strength, blood diagnostic parameters, and intestinal microbiome characterization. The changes in clinically relevant secondary outcome values will be used to make a power calculation for definite trial.

DISCUSSION

This pilot trial will address two common challenges in SCI research: the difficulty to recruit enough participants for a sufficiently powered study and the ability to collect data within the limits of a realistic budget and time frame. Upon demonstrated feasibility of the intervention and study procedures, the intervention will be evaluated in a definitive controlled trial comprising a larger sample of para-athletes (elite, engaged, or recreationally active) individuals with a SCI.

TRIAL REGISTRATION

NCT04659408.

Ethical and epistemic issues in the design and conduct of pragmatic stepped-wedge cluster randomized clinical trials

Stepped-wedge cluster randomized trial (SW-CRT) designs are increasingly employed in pragmatic research; they differ from traditional parallel cluster randomized trials in which an intervention is delivered to a subset of clusters, but not to all. In a SW-CRT, all clusters receive the intervention under investigation by the end of the study. This approach is thought to avoid ethical concerns about the denial of a desired intervention to participants in control groups. Such concerns have been cited in the literature as a primary motivation for choosing SW-CRT design, however SW-CRTs raise additional ethical concerns related to the delayed implementation of an intervention and consent. Yet, PCT investigators may choose SW-CRT designs simply because they are concerned that other study designs are infeasible. In this paper, we examine justifications for the use of SW-CRT study design, over other designs, by drawing on the experience of the National Institutes of Health's Health Care Systems Research Collaboratory (NIH Collaboratory) with five pragmatic SW-CRTs. We found that decisions to use SW-CRT design were justified by practical and epistemic reasons rather than ethical ones. These include concerns about feasibility, the heterogeneity of cluster characteristics, and the desire for simultaneous clinical evaluation and implementation. In this paper we compare the potential benefits of SW-CRTs against the ethical and epistemic challenges brought forth by the design and suggest that the choice of SW-CRT design must balance epistemic, feasibility and ethical justifications. Moreover, given their complexity, such studies need rigorous and informed ethical oversight.

Evaluating management of progressive disease for control arm patients in trials of first line PD-1 or PD-L1 inhibitor-based treatment for metastatic solid tumours

INTRODUCTION

First-line trials evaluating programmed cell death protein 1/programmed-death ligand 1 inhibitors (PDI) are often preceded by FDA approvals of PDI in second-line settings; however, many control-arm patients in these first-line trials do not receive PDI at disease progression. We performed a systematic analysis of trials evaluating upfront use of PDI in metastatic solid tumours to (1) quantify the number of control-arm patients that receive PDI upon disease progression and (2) the timing difference between FDA approval for a PDI in the second-line setting and (3) enrolment period for the same drug in a first-line trial.

METHODS

Using the Drugs@FDA website, we evaluated all approvals for first-line and second-line PDI in metastatic solid tumours through December 2021. From corresponding trials, we calculated the timing difference between second-line approval of a PDI and start/end of accrual of first-line trials and management of disease progression for control-arm patients.

RESULTS

25/32 approvals for upfront PDI were preceded by approval of a PDI in the second-line of the same disease and included in this analysis. First-line trials start of accrual preceded approval of a PDI by a mean of 4 months, median 6 months and ended accrual by a mean and median of 14 after second-line approval. A mean of 51% of control-arm patients received subsequent therapy, with a mean of 33% of these patients receiving a PDI.

CONCLUSION

This analysis shows that many control-arm patients in the included trials did not receive a PDI with already established efficacy at any point during their recorded treatment. This underscores a need to standardise the approach to disease progression for control-arm patients to reflect evolving standards of care. This analysis is limited by a lack of individual patient-level data, heterogeneity of included trials and exclusion of first-line PDI trials that did not meet their primary endpoint.

Design of the ANal Cancer/HSIL Outcomes Research study (ANCHOR study): A randomized study to prevent anal cancer among persons living with HIV

It is well established that persons living with HIV (PLWH) have highly elevated rates of anal HSIL and anal cancer compared with those who are not living with HIV. The 5-year risk of anal cancer following anal HSIL has been reported to be as high as 14.1% among PLWH compared with 3.2% among those who are not living with HIV. To address these concerns, the AIDS Malignancy Consortium completed a large-scale, randomized trial to compare strategies for the prevention of anal cancer among PLWH with anal HSIL. The objective of the study was to determine whether treating anal HSIL was effective in reducing the incidence of anal cancer in PLWH compared with active monitoring. This paper describes the design of the ANal Cancer/HSIL Outcomes Research Study (ANCHOR) with respect to estimating the anal cancer event rate in this high risk population.

Age Demographics of Subjects Enrolled in Global, Interventional Phase 3 Melanoma Clinical Trials

Background

Melanoma is a skin cancer with a rising worldwide incidence of just over 280,000 individuals with the greatest burden of illness in European, New Zealander, and Australian populations. Patients are diagnosed with melanoma with the mean and median ages being 65 and 59 years old, respectively. Phase 3 trials not only provide a wide representation of the target population but also study the efficacy for a certain intervention.

Objective

The objective of this literature review is to analyze patient demographics of phase 3 trials for melanoma and identify if there is a true disparity between the clinical trial age demographics and the natural epidemiological age demographics.

Data Sources

The authors conducted a search on clinicaltrials.gov, a publicly available resource that lists clinical trials and their data. The reported mean and median ages for each trial were extracted after determining if each trial meets our inclusion criteria. Weighted mean and median ages were calculated using an online calculator.

Data Summary

Data from 35 trials were evaluated with 30 trials reporting a weighted mean age of 55.85 years and 5 trials reporting a weighted median age of 55.14 years.

Conclusion

Based on the results, melanoma clinical trials enroll patients who are younger than the epidemiological mean and median ages. Due to this underrepresentation of the elderly patients with melanoma, clinical trials may provide limited application for the use of their results.

Machine Learning and Artificial Intelligence in Pharmaceutical Research and Development: a Review

Over the past decade, artificial intelligence (AI) and machine learning (ML) have become the breakthrough technology most anticipated to have a transformative effect on pharmaceutical research and development (R&D). This is partially driven by revolutionary advances in computational technology and the parallel dissipation of previous constraints to the collection/processing of large volumes of data. Meanwhile, the cost of bringing new drugs to market and to patients has become prohibitively expensive. Recognizing these headwinds, AI/ML techniques are appealing to the pharmaceutical industry due to their automated nature, predictive capabilities, and the consequent expected increase in efficiency. ML approaches have been used in drug discovery over the past 15–20 years with increasing sophistication. The most recent aspect of drug development where positive disruption from AI/ML is starting to occur, is in clinical trial design, conduct, and analysis. The COVID-19 pandemic may further accelerate utilization of AI/ML in clinical trials due to an increased reliance on digital technology in clinical trial conduct. As we move towards a world where there is a growing integration of AI/ML into R&D, it is critical to get past the related buzz-words and noise. It is equally important to recognize that the scientific method is not obsolete when making inferences about data. Doing so will help in separating hope from hype and lead to informed decision-making on the optimal use of AI/ML in drug development. This manuscript aims to demystify key concepts, present use-cases and finally offer insights and a balanced view on the optimal use of AI/ML methods in R&D.

Feasibility of transcutaneous auricular vagus nerve stimulation in treatment of drug resistant epilepsy: A multicenter prospective study

BACKGROUND

Transcutaneous auricular vagus nerve stimulation (ta-VNS) is a new non-invasive technique developed as treatment option for drug resistant epilepsy. A few studies have been carried out showing that the efficacy and tolerability of ta-VNS is comparable with traditional implanted VNS but the feasibility of the therapy has been poorly described. This study aimed to explore potential clinical benefits of ta-VNS and to evaluate adaptation, compliance, as well as the usability of the device from a service design perspective.

METHODS

A prospective, multicenter, clinical, investigator-initiated trial was conducted using the NEMOS® ta-VNS device. After eight weeks baseline, all subjects started ta-VNS with individually adjusted currents for four hours per day for six-months (first endpoint) followed by optional 12 months follow-up (second endpoint). The primary outcome was six months retention rate of ta-VNS therapy. Secondary outcomes included the user retention rate at 12 months follow-up, compliance, changes in scores of psychometric measures. For the study of feasibility, a service design questionnaire on medical devices used in the home was developed.

RESULTS

In total 37 subjects had been included in the study after 45 months where the study was prematurely terminated due to recruitment problems and due to a high drop-out rate. Twenty-two subjects (59 %) completed the first six months of the study and in total six subjects (16 %) completed the following 12 months follow-up. The reasons for discontinuation were a mixture of medical and practical issues of which the majority were related to a combination of both. Those, who managed to continue to use ta-VNS throughout the study, gave generally higher scores for the device usability and compatibility with lifestyle. The study turned out to be inadequately powered to reach any conclusion in terms of the clinical benefits of ta-VNS but present an example of difficulties that are encountered in conducting high-quality studies with digital devices.

CONCLUSION

The feasibility of ta-VNS therapy showed to be relatively modest which is most likely due to practical usability issues and lifestyle fits. The results of this study stress the importance of generating data based on patients experiences at an early stage during the development phase and when designing clinical trials on medical devices that depend on patient's active participation and motivation.

Incorporating systems-level stakeholder perspectives into the clinical trial design of school-supervised asthma therapy

RATIONALE

Few evidence-based public health interventions are adopted in practice, in part due to a disconnect between the outcomes measured in clinical trials and the outcomes important to stakeholders that determine implementation in real-world practice. AsthmaLink is a school-supervised asthma therapy program which partners pediatric providers, school nurses, and families. To inform the design of a cluster randomized controlled trial of AsthmaLink, we elicited systems-level stakeholder input.

METHODS

Maximum variation sampling was used to recruit 18 stakeholders to participate in semi-structured interviews that were recorded, transcribed, and open coded: Department of Public Health officials (n = 4), school officials (n = 4), pediatric practice managers (n = 3), health insurance officials (n = 4), and legislators (n = 3). Thematic analysis was used to identify common themes related to stakeholder priorities for clinical trial design and perceived barriers to AsthmaLink adoption.

RESULTS

Stakeholder groups identified common priorities for the clinical trial design, including examination of the extent to which AsthmaLink (1) reduces health care utilization, (2) is cost effective (2) addresses health disparities, (3) reduces school absenteeism, and (4) educates families about asthma. Stakeholder groups reported potential barriers to AsthmaLink adoption, including challenges pertaining to (1) securing resources, staffing, and reimbursement, (2) variability across school districts, and (3) standing out amidst multiple programs vying for resources.

CONCLUSIONS

Systems-level stakeholder input informed refinements to the clinical trial design of a school-supervised therapy program including outcome and implementation measures and choice of study population. Incorporating systems-level stakeholder perspectives into clinical trial design is critical to achieve adoption of evidence-based interventions into practice.

Using simulated infectious disease outbreaks to inform site selection and sample size for individually randomized vaccine trials during an ongoing epidemic

Background:

Novel strategies are needed to make vaccine efficacy trials more robust given uncertain epidemiology of infectious disease outbreaks, such as arboviruses like Zika. Spatially resolved mathematical and statistical models can help investigators identify sites at highest risk of future transmission and prioritize these for inclusion in trials. Models can also characterize uncertainty in whether transmission will occur at a site, and how nearby or connected sites may have correlated outcomes. A structure is needed for how trials can use models to address key design questions, including how to prioritize sites, the optimal number of sites, and how to allocate participants across sites.

Methods:

We illustrate the added value of models using the motivating example of Zika vaccine trial planning during the 2015–2017 Zika epidemic. We used a stochastic, spatially resolved, transmission model (the Global Epidemic and Mobility model) to simulate epidemics and site-level incidence at 100 high-risk sites in the Americas. We considered several strategies for prioritizing sites (average site-level incidence of infection across epidemics, median incidence, probability of exceeding 1% incidence), selecting the number of sites, and allocating sample size across sites (equal enrollment, proportional to average incidence, proportional to rank). To evaluate each design, we stochastically simulated trials in each hypothetical epidemic by drawing observed cases from site-level incidence data.

Results:

When constraining overall trial size, the optimal number of sites represents a balance between prioritizing highest-risk sites and having enough sites to reduce the chance of observing too few endpoints. The optimal number of sites remained roughly constant regardless of the targeted number of events, although it is necessary to increase the sample size to achieve the desired power. Though different ranking strategies returned different site orders, they performed similarly with respect to trial power. Instead of enrolling participants equally from each site, investigators can allocate participants proportional to projected incidence, though this did not provide an advantage in our example because the top sites had similar risk profiles. Sites from the same geographic region may have similar outcomes, so optimal combinations of sites may be geographically dispersed, even when these are not the highest ranked sites.

Conclusion:

Mathematical and statistical models may assist in designing successful vaccination trials by capturing uncertainty and correlation in future transmission. Although many factors affect site selection, such as logistical feasibility, models can help investigators optimize site selection and the number and size of participating sites. Although our study focused on trial design for an emerging arbovirus, a similar approach can be made for any infectious disease with the appropriate model for the particular disease.

Clinical Trial Considerations in Neuro-oncology

Clinical trials play a critical role in discovering new treatments, but the path to regulatory approval can be cumbersome and time consuming. Efforts to increase the efficiency and interpretability of clinical trials within the neuro-oncology community have focused on standardization of response assessment, development of consensus guidelines for clinical trial conduct, decentralization of clinical trials, removal of barriers to clinical trial accrual, and re-examination of patient eligibility criteria.

Clinical Trial Design for Disease-Modifying Therapies for Genetic Epilepsies

Although trials with anti-seizure medications (ASMs) have not shown clear anti-epileptogenic or disease-modifying activity in humans to date, rapid advancements in genomic technology and emerging gene-mediated and gene replacement options offer hope for the successful development of disease-modifying therapies (DMTs) for genetic epilepsies. In fact, more than 26 potential DMTs are in various stages of preclinical and/or clinical development for genetic syndromes associated with epilepsy. The scope of disease-modification includes but is not limited to effects on the underlying pathophysiology, the condition's natural history, epilepsy severity, developmental achievement, function, behavior, sleep, and quality of life. While conventional regulatory clinical trials for epilepsy therapeutics have historically focused on seizure reduction, similarly designed trials may prove ill-equipped to identify these broader disease-modifying benefits. As we look forward to this pipeline of DMTs, focused consideration should be given to the challenges they pose to conventional clinical trial designs for epilepsy therapeutics. Just as DMTs promise to fundamentally alter how we approach the care of patients with genetic epilepsy syndromes, DMTs likewise challenge how we traditionally construct and measure the success of clinical trials. In the following, we briefly review the historical and preclinical frameworks for DMT development for genetic epilepsies and explore the many novel challenges posed for such trials, including the choice of suitable outcome measures, trial structure, timing and duration of treatment, feasible follow-up period, varying safety profile, and ethical concerns.

Nutritional Ketosis in Parkinson's Disease - a Review of Remaining Questions and Insights

Nutritional ketosis has promise for treating Parkinson's disease. Three previous studies explored the use of a ketogenic diet in cohorts with Parkinson's disease, and, while not conclusive, the data suggest non-motor symptom benefit. Before the ketogenic diet can be considered as a therapeutic option, it is important to establish with greater certainty that there is a reliable symptomatic benefit: which symptoms or groups of symptoms are impacted (if non-motor symptoms, which ones, and by which mechanism), what timescale is needed to obtain benefit, and how large an effect size can be achieved? To accomplish this, further investigation into the disease mechanisms based on pre-clinical data and hints from the clinical outcomes to date is useful to understand target engagement and gauge which mechanism could lead to a testable hypothesis. We review research pertaining to ketogenic diet, exogenous ketones, fasting, clinical studies, and theoretical review papers regarding therapeutic mechanisms from direct ketone body signaling and indirect metabolic effects. Through discussion of these findings and consideration of whether the ketogenic diet can be regarded as therapeutically useful for adjunctive therapy for Parkinson's disease, we identify remaining questions for the clinician to consider prior to recommending this diet.

Prioritisation and design of clinical trials

Clinical trials require participation of numerous patients, enormous research resources and substantial public funding. Time-consuming trials lead to delayed implementation of beneficial interventions and to reduced benefit to patients. This manuscript discusses two methods for the allocation of research resources and reviews a framework for prioritisation and design of clinical trials. The traditional error-driven approach of clinical trial design controls for type I and II errors. However, controlling for those statistical errors has limited relevance to policy makers. Therefore, this error-driven approach can be inefficient, waste research resources and lead to research with limited impact on daily practice. The novel value-driven approach assesses the currently available evidence and focuses on designing clinical trials that directly inform policy and treatment decisions. Estimating the net value of collecting further information, prior to undertaking a trial, informs a decision maker whether a clinical or health policy decision can be made with current information or if collection of extra evidence is justified. Additionally, estimating the net value of new information guides study design, data collection choices, and sample size estimation. The value-driven approach ensures the efficient use of research resources, reduces unnecessary burden to trial participants, and accelerates implementation of beneficial healthcare interventions.

Evaluation by simulation of clinical trial designs for evaluation of treatment during a viral haemorrhagic fever outbreak

Background

Viral haemorrhagic fevers are characterized by irregular outbreaks with high mortality rate. Difficulties arise when implementing therapeutic trials in this context. The outbreak duration is hard to predict and can be short compared to delays of trial launch and number of subject needed (NSN) recruitment. Our objectives were to compare, using clinical trial simulation, different trial designs for experimental treatment evaluation in various outbreak scenarios.

Methods

Four type of designs were compared: fixed or group-sequential, each being single- or two-arm. The primary outcome was 14-day survival rate. For single-arm designs, results were compared to a pre-trial historical survival rate p_H. Treatments efficacy was evaluated by one-sided tests of proportion (fixed designs) and Whitehead triangular tests (group-sequential designs) with type-I-error = 0.025. Both survival rates in the control arm p_C and survival rate differences Δ (including 0) varied. Three specific cases were considered: “standard” (fixed p_C, reaching NSN for fixed designs and maximum sample size N_Max for group-sequential designs); “changing with time” (increased p_C over time); “stopping of recruitment” (epidemic ends). We calculated the proportion of simulated trials showing treatment efficacy, with K = 93,639 simulated trials to get a type-I-error PI_95% of [0.024;0.026].

Results

Under H₀ (Δ = 0), for the “standard” case, the type-I-error was maintained regardless of trial designs. For “changing with time” case, when p_C > p_H, type-I-error was inflated, and when p_C < p_H it decreased. Wrong conclusions were more often observed for single-arm designs due to an increase of Δ over time. Under H₁ (Δ = + 0.2), for the “standard” case, the power was similar between single- and two-arm designs when p_C = p_H. For “stopping of recruitment” case, single-arm performed better than two-arm designs, and fixed designs reported higher power than group-sequential designs. A web R-Shiny application was developed.

Conclusions

At an outbreak beginning, group-sequential two-arm trials should be preferred, as the infected cases number increases allowing to conduct a strong randomized control trial. Group-sequential designs allow early termination of trials in cases of harmful experimental treatment. After the epidemic peak, fixed single-arm design should be preferred, as the cases number decreases but this assumes a high level of confidence on the pre-trial historical survival rate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01287-w.

Design of a Phase III immunogenicity and safety study evaluating two-dose regimens of 9-valent human papillomavirus (9vHPV) vaccine with extended dosing intervals

HPV vaccines are widely licensed as two-dose regimens, 6-12 months apart, for adolescents. Extended intervals between doses may be necessary due to resource constraints or vaccination program disruption. This international, multicenter, open-label study (NCT04708041) will evaluate the safety and immunogenicity of two-dose 9vHPV vaccine regimens with extended intervals of 1-5 years between doses in boys/girls compared with a standard three-dose regimen in women. Participants (planned N = 700) will be enrolled into six cohorts; Cohort 0: boys/girls aged 10-15 years who received one 9vHPV vaccine dose ≥1 year before enrollment without completing the series will receive one study dose of 9vHPV vaccine at day 1; Cohorts 1-4: HPV vaccination-naïve boys/girls aged 9-14 years will receive two doses (day 1 and month 12, 24, 36, or 60); Cohort 5: HPV vaccination-naïve women aged 16-26 years will receive three doses (day 1, months 2 and 6). Primary analyses will be based on serological responses 1 month after final vaccine dose. Co-primary objectives will (1) evaluate non-inferiority of geometric mean titers in each of Cohorts 1-4 versus Cohort 5, and (2) characterize antibody responses in Cohort 0, accounting for the interval between commercial and study vaccine dose. Injection-site and systemic adverse events (AEs) will be collected for 15 days and serious AEs for 12 months post-vaccination; vaccine-related serious AEs and deaths will be collected throughout the study. Results will inform completion of vaccination in individuals who did not complete the recommended series and guide implementation of vaccination programs in resource-limited settings.

Systematic review of outcome domains and instruments used in designs of clinical trials for interventions that seek to restore bilateral and binaural hearing in adults with unilateral severe to profound sensorineural hearing loss ('single-sided deafness')

BACKGROUND

This systematic review aimed to identify, compare and contrast outcome domains and outcome instruments reported in studies investigating interventions that seek to restore bilateral (two-sided) and/or binaural (both ears) hearing in adults with single-sided deafness (SSD). Findings can inform the development of evidence-based guidance to facilitate design decisions for confirmatory trials.

METHODS

Records were identified by searching MEDLINE, EMBASE, PubMed, CINAHL, ClinicalTrials.gov, ISRCTN, CENTRAL, WHO ICTRP and the NIHR UK clinical trials gateway. The search included records published from 1946 to March 2020. Included studies were those as follows: (a) recruiting adults aged 18 years or older diagnosed with SSD of average threshold severity worse than 70 dB HL in the worse-hearing ear and normal (or near-normal) hearing in the better-hearing ear, (b) evaluating interventions to restore bilateral and/or binaural hearing and (c) enrolling those adults in a controlled trial, before-and-after study or cross-over study. Studies that fell just short of the participant eligibility criteria were included in a separate sensitivity analysis.

RESULTS

Ninety-six studies were included (72 full inclusion, 24 sensitivity analysis). For fully included studies, 37 exclusively evaluated interventions to re-establish bilateral hearing and 29 exclusively evaluated interventions to restore binaural hearing. Overall, 520 outcome domains were identified (350 primary and 170 secondary). Speech-related outcome domains were the most common (74% of studies), followed by spatial-related domains (60% of studies). A total of 344 unique outcome instruments were reported. Speech-related outcome domains were measured by 73 different instruments and spatial-related domains by 43 different instruments. There was considerable variability in duration of follow-up, ranging from acute (baseline) testing to 10 years after the intervention. The sensitivity analysis identified no additional outcome domains.

CONCLUSIONS

This review identified large variability in the reporting of outcome domains and instruments in studies evaluating the therapeutic benefits and harms of SSD interventions. Reports frequently omitted information on what domains the study intended to assess, and on what instruments were used to measure which domains.

TRIAL REGISTRATION

The systematic review protocol is registered on PROSPERO (International Prospective Register of Systematic Reviews): Registration Number CRD42018084274 . Registered on 13 March 2018, last revised on 7th of May 2019.

Design and Rationale of the Global Phase 3 NEURO-TTRansform Study of Antisense Oligonucleotide AKCEA-TTR-LRx (ION-682884-CS3) in Hereditary Transthyretin-Mediated Amyloid Polyneuropathy

Introduction

AKCEA-TTR-L_Rx is a ligand-conjugated antisense (LICA) drug in development for the treatment of hereditary transthyretin amyloidosis (hATTR), a fatal disease caused by mutations in the transthyretin (TTR) gene. AKCEA-TTR-L_Rx shares the same nucleotide sequence as inotersen, an antisense medicine approved for use in hATTR polyneuropathy (hATTR-PN). Unlike inotersen, AKCEA-TTR-L_Rx is conjugated to a triantennary N-acetylgalactosamine moiety that supports receptor-mediated uptake by hepatocytes, the primary source of circulating TTR. This advanced design increases drug potency to allow for lower and less frequent dosing. The NEURO-TTRansform study will investigate whether AKCEA-TTR-L_Rx is safe and efficacious, with the aim of improving neurologic function and quality of life in hATTR-PN patients.

Methods/Design

Approximately 140 adults with stage 1 (independent ambulation) or 2 (requires ambulatory support) hATTR-PN are anticipated to enroll in this multicenter, open-label, randomized, phase 3 study. Patients will be assigned 6:1 to AKCEA-TTR-L_Rx 45 mg subcutaneously every 4 weeks or inotersen 300 mg once weekly until the prespecified week 35 interim efficacy analysis, after which patients receiving inotersen will receive AKCEA-TTR-L_Rx 45 mg subcutaneously every 4 weeks. All patients will then receive AKCEA-TTR-L_Rx through the remainder of the study treatment period. The final efficacy analysis at week 66 will compare the AKCEA-TTR-L_Rx arm with the historical placebo arm from the phase 3 trial of inotersen (NEURO-TTR). The primary outcome measures are between-group differences in the change from baseline in serum TTR, modified Neuropathy Impairment Score + 7, and Norfolk Quality of Life—Diabetic Neuropathy questionnaire.

Conclusion

NEURO-TTRansform is designed to determine whether targeted delivery of AKCEA-TTR-L_Rx to hepatocytes with lower and less frequent doses will translate into clinical and quality-of-life benefits for patients with hATTR-PN.

Trial Registration

The study is registered at ClinicalTrials.gov (NCT04136184) and EudraCT (2019-001698-10).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00235-6.

Hereditary transthyretin amyloidosis with peripheral neuropathy (hATTR-PN for short) is a rare inherited condition.

In hATTR-PN, a protein called transthyretin (TTR for short) builds up and damages nerves throughout the body.

This neuropathy causes symptoms such as weakness, loss of sensation, and pain.

Currently available medicines can slow disease progression, but researchers are looking for more effective treatments with fewer side effects.

AKCEA-TTR-L_Rx is an investigational treatment for hATTR-PN.

AKCEA-TTR-L_Rx prevents the liver from making TTR, reducing the amount that causes disease progression.

It is similar to an existing treatment called inotersen, but designed for better delivery to the liver and is more potent.

This article describes the NEURO-TTRansform study that will evaluate how effective AKCEA-TTR-L_Rx is for treating hATTR-PN.

Around 140 adults with hATTR-PN from the USA, Canada, and Europe will be able to take part in this study.

The study treatment period will be 85 weeks long. People will receive injections underneath the skin of either:

AKCEA-TTR-L_Rx every 4 weeks, or

Inotersen once a week for 35 weeks, followed by a switch to AKCEA-TTR-L_Rx every 4 weeks.

People may continue to receive AKCEA-TTR-L_Rx after the study treatment period ends.

In this study, researchers will compare results from people who received AKCEA-TTR-L_Rx to results from people who received no active ingredients (called placebo) in a similar study (called NEURO-TTR).

Researchers will measure the differences in peoples’:

Neuropathy symptoms.

Quality of life.

TTR protein levels in the blood.