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Definitive evidence of clinical efficacy in a Phase 3 trial is best shown by a beneficial impact on a clinically meaningful endpoint-that is, an endpoint that directly measures how a patient feels (symptoms), functions (the ability to perform activities in daily life), or survives. In idiopathic pulmonary fibrosis (IPF), we believe the endpoints that best meet these criteria are all-cause mortality and all-cause nonelective hospitalization. There are no validated measures of symptoms or broader constructs such as health status or functional status in IPF. A surrogate endpoint is defined as an indirect measure that is intended to substitute for a clinically meaningful endpoint. Surrogate endpoints can be appropriate outcome measures if validated. However, validation requires substantial evidence that the effect of an intervention on a clinically meaningful endpoint is reliably predicted by the effect of an intervention on the surrogate endpoint. For patients with IPF, there are currently no validated surrogate endpoints. [ABSTRACT FROM AUTHOR]

Rationale: Iseganan, an antimicrobial peptide, is active against aerobic and anaerobic gram-positive and gram-negative bacteria as well as fungi and yeasts. The drug has shown little resistance in vitro and to be safe and well tolerated in 800 patients with cancer treated for up to 6 wk.Objectives: To determine the efficacy of iseganan for the prevention of ventilator-associated pneumonia (VAP).Methods: Mechanically ventilated patients in the United States and Europe were randomized to oral topical iseganan or placebo (1:1) and treated six times per day while intubated for up to 14 d. Patients were eligible if randomized within 24 h of intubation and estimated to survive and remain mechanically ventilated for 48 h or more. The primary efficacy endpoint of the study was VAP measured among survivors at Day 14.Measurements and Main Results: A total of 709 patients were randomized and received at least one dose of study drug. The two groups were comparable at baseline except iseganan-treated patients were, on average, 3 yr older. The rate of VAP among survivors at Day 14 was 16% (45/282) in patients treated with iseganan and 20% (57/284) in those treated with placebo (p = 0.145). Mortality at Day 14 was 22.1% (80/362) in the iseganan group compared with 18.2% (63/347) in the placebo group (p = 0.206). No pattern of excess adverse events in the iseganan group compared with placebo was observed.Conclusions: Iseganan is not effective in improving outcome in patients on prolonged mechanical ventilation. [ABSTRACT FROM AUTHOR]

Objective: To determine the effectiveness of two adjuvant therapy regimens in improving surgical cure rates in stage III (Dukes stage C) colon cancer.Design: Randomized, concurrently controlled clinical trial.Setting: Major cancer centers, universities, and community clinics affiliated with the North Cancer Treatment Group, the Southwest Oncology Group, and the Eastern Cooperative Oncology Group.Patients: Those who had had curative-intent resections of stage III colon cancer in the previous 1 to 5 weeks.Intervention: Patients were assigned to observation only, to levamisole alone (50 mg orally three times/d for 3 days, repeated every 2 weeks for 1 year), or to this regimen of levamisole plus fluorouracil (450 mg/m2 body surface area intravenously daily for 5 days and then, beginning at 28 days, weekly for 48 weeks).Measurements: Rates of cancer recurrence and death. Early- and late-treatment side effects.Results: With all 929 eligible patients able to be followed for 5 years or more (median follow-up, 6.5 years), fluorouracil plus levamisole reduced the recurrence rate by 40% (P < 0.0001) and the death rate by 33% (P = 0.0007). Levamisole reduced the recurrence rate by only 2% and the death rate by only 6%. With few exceptions, toxicity was mild and patient compliance was excellent. No evidence of late side effects was seen.Conclusion: Fluorouracil plus levamisole is tolerable adjuvant therapy to surgery; it has been confirmed to substantially increase cure rates for patients with high-risk (stage III) colon cancer. It should be considered standard treatment for all such patients not entered into clinical trials. [ABSTRACT FROM AUTHOR]

New and emerging therapies might provide benefit in patients with pulmonary arterial hypertension. Their efficacy and safety will be compared with existing combination therapies in randomized clinical trials. Appropriate end points for these trials need to be identified: these will include exercise testing, the composite end point of time to clinical worsening, and hemodynamic markers, including advanced imaging modalities and biomarkers. Quality-of-life questionnaires are useful and important secondary end points; pulmonary arterial hypertension-specific questionnaires are currently being developed. Advantages and disadvantages of various trial designs, including placebo-controlled monotherapy or add-on trials, noninferiority studies, and withdrawal trials are also discussed. [ABSTRACT FROM AUTHOR]

Clinical trials in pulmonary arterial hypertension (PAH) have led to the approval of several effective treatments that improve symptoms, exercise capacity and clinical outcomes. In phase 3 clinical trials, primary end-points must reflect how a patient "feels, functions or survives". In a rare disease like PAH, with an ever-growing number of treatment options and numerous candidate therapies being studied, future clinical trials are now faced with challenges related to sample size requirements, efficiency and demonstration of incremental benefit on traditional end-points in patients receiving background therapy with multiple drugs. Novel clinical trial end-points, innovative trial designs and statistical approaches and new technologies may be potential solutions to tackle the challenges facing future PAH trials, but these must be acceptable to patients and regulatory bodies while preserving methodological rigour. In this World Symposium on Pulmonary Hypertension task force article, we address emerging trial end-points and designs, biomarkers and surrogate end-point validation, the concept of disease modification, challenges and opportunities to address diversity and representativeness, and the use of new technologies such as artificial intelligence in PAH clinical trials., Competing Interests: Conflict of interest: J. Weatherald declares grants or contracts to their institution from Janssen, Bayer, Merck, AstraZeneca and Sanofi; consulting fees, payment or honoraria to themselves, travel support and paid membership of an Advisory Board from Janssen and Merck; payment for expert testimony from Sprigings Intellectual Property Law; unpaid membership of a Data Safety Monitoring Board drom Université Laval; and unpaid membership of the medical advisory committee of the Pulmonary Hypertension Association of Canada and the scientific medical advisory committee of the Pulmonary Vascular Research Institute. T.R. Fleming declares no competing interests. M.R. Wilkins declares grants or contracts from the British Heart Foundation (RE/18/4/34215 centre support); consulting fees from MorphogenIX (advisory committee), VIVUS (study protocol advisory meeting), Janssen and Kinaset (study advisory boards) and Chiesi, Aerami and Benevolent AI (consultancy); payment for expert testimony from Pennington Marches and Sprigings; support for travel to scientific meetings from Apollo Therapeutics; patents planned, issued or pending (Imperial Innovations: patent submitted for prognostic protein model presented in this manuscript; patent for ZIP12 as a drug target; patent for TSPO as a drug target); membership of an adjudication committee for three clinical trials for Acceleron; membership of study safety committees for GSK and Novartis; a role as a trustee of the Pulmonary Vascular Research Institute; and stock options in W12 Therapeutics. T.M. Cascino delares grants from NHLBI (K12 HL138039) and Johnson & Johnson Innovative Medicine; consulting fees from and participation on a Data Safety Monitoring Board or Advisory Board for Merck; and payment or honoraria from Total CME. M.A. Psotka declares no competing interests. R. Zamanian declares grants to their institution from Gossamer Bio, Merck, United Therapeutics and Janssen; consulting fees from Gossamer Bio, Morphogen IX, Merck and Aerovate; patents planned, issued or pending for FK506 for treatment of pulmonary hypertension; participation on a Data Safety Monitoring Board or Advisory Board for Aerovate; and stock options in REVIVA. W. Seeger declares consulting fees from United Therapeutics, Abivax, Tiakis Biotech AG, Pfizer, Liquidia, Medspray BV and Pieris Pharmaceuticals. N. Galiè declares grants or contracts from Janssen, Actelion and Merck; consulting fees from Janssen, Actelion, Chiesi and Ferrer; payment or honoraria from Janssen, Actelion and Chiesi; support for attending meetings and/or travel from Dompe; and participation on a Data Safety Monitoring Board or Advisory Board from Janssen, Actelion and Ferrer. M. Gomberg-Maitland declares consulting fees from Acceleron/Merck (steering committee), Aerami (until 2023), Janssen (consultancy), JucaBio (steering committee), Keros (steering committee) and United Therapeutics (Jenesis Young Investigator Grant Chairman); support for attending the ERS Congress from Merck; participation on a Data Safety Monitoring board for Acceleron/Merck (until 2023) and Janssen (until 2023); and unpaid roles as Treasurer of ISHLT and a member of the United Therapeutics Scientific Advisory Board., (Copyright ©The authors 2024.)

Background/objectives: The aim of this study was to estimate the effect of a 6 months' treatment course of the innate immune modulator NP001 (a pH-adjusted intravenous formulation of purified sodium chlorite), on disease progression, as measured by overall survival (OS) in patients with amyotrophic lateral sclerosis., Methods: Blinded survival data were retrospectively collected for 268 of the 273 patients who had participated in two phase 2 placebo-controlled clinical trials of NP001 (ClinicalTrials.gov: NCT01281631 and NCT02794857) and received at least one dose of either 1 mg/kg or 2 mg/kg of NP001 as chlorite based on actual body weight, or placebo. Kaplan-Meier methods were used on the intent-to-treat population to estimate survival probabilities., Results: In the overall population, the median OS was 4.8 months (2.7 years [95% CI: 2.3, 3.5] in the 2 mg/kg NP001group and 2.3 years [95% CI: 1.8, 2.9] in the placebo group). Hazard ratio (HR): 0.77 (95% CI: 0.57, 1.03), p = 0.073. Among patients aged ≤ 65 years, the median OS for the 2 mg/kg NP001 group was 10.8 months (3.3 years [95% CI: 2.4, 3.8] in the 2 mg/kg NP001 group and 2.4 years [95% CI: 1.7, 3.3] in the placebo group). HR: 0.69 (95% CI: 0.50, 0.95). No differences were observed in the 1 mg/kg NP001 group or in patients aged > 65 years., Conclusions: The findings from this study suggest that a 6 months' treatment course of NP001 resulted in a 4.8-month increase in overall survival in patients with ALS. The findings from this study indicate that targeting inflammation associated with the innate immune system may provide a pathway for new therapeutic options for the treatment of ALS.

AbstractClinical trials investigating novel or high-risk interventions often use data monitoring committees (DMCs) to ensure that the participants' best interests are safeguarded. The typical DMC charter describes procedures by which the DMC operates, including important details concerning organizational structure, membership, meeting frequency, statistical monitoring guidelines, and contents of DMC reports for interim review. These charters, however, are not routinely publicly available; in some cases, their access could be important to the interpretation of trial results. We recommend including DMC charters for such trials in ClinicalTrials.gov at the time of trial completion; trial protocols, informed consent documents, and statistical analysis plans are already available in this repository.

Competing Interests: We thank the patients with IPF for their very kind participation as volunteers in clinical trials and, along with their family and caregivers, for partnering with their clinical team to contribute and enhance understanding and management of their disease, despite being confronted with their own sufferings, and consequences of IPF. GR declares funding from National Heart, Lung and Blood Institute/National institutes of health; received consulting fees from BMS, United Therapeutics, and Veracyte; was on Data Safety Monitoring Board of Avalyn (not paid); GR was the chair of the Idiopathic pulmonary fibrosis international guideline committee for the official document of the American Thoracic Society and was on a Scientific Advisory Board of the Pulmonary Fibrosis Foundation; and was a consultant (unpaid) for Bellerophan; Gilead, Fibrogen, Nitto, Novartis, Roche-Hoffman-Genentech. TF declares no competing interests.

Clinical trials are vital for assessing therapeutic interventions. The associated data monitoring committees (DMCs) safeguard patient interests and enhance trial integrity, thus promoting timely, reliable evaluations of those interventions. We face an urgent need to recruit and train new DMC members. The HFC (Heart Failure Collaboratory), a multidisciplinary public-private consortium of academics, trialists, patients, industry representatives, and government agencies, is working to improve the clinical trial ecosystem. The HFC aims to improve clinical trial efficiency and quality by standardizing concepts, and to help meet the demand for experienced individuals on DMCs by creating a standardized approach to training new members. This paper discusses the HFC's training workshop, and an apprenticeship model for new DMC members. It describes opportunities and challenges DMCs face, along with common myths and best practices learned through previous experiences, with an emphasis on data confidentiality and need for quality independent statistical reporting groups., Competing Interests: Funding Support and Author Disclosures Dr Fleming has received consulting fees from the National Institutes of Health, the World Health Organization, the Food and Drug Administration, and the pharmaceutical and biotech industry in the design, monitoring, and analysis of clinical trials; and he has received fees for serving on several industry-sponsored Data Monitoring Committees (DMCs). Dr Wittes has received compensation for her membership on several DMCs sponsored by industry, government, and not-for-profit organizations; and has received consulting fees from a variety of pharmaceutical and medical device companies. Dr Bristow is the President/CEO/Director at ARCA biopharma. Dr Rockhold has received consulting fees from Intercept, Clover, and Inventprise; has received compensation for serving on several industry-sponsored DMCs; and holds stock in Clover, GSK, Athira, Spence, Adaptic, and Doctor Evidence. Dr Claggett has received consulting fees from Alnylam, Axon, Cardior, Cardurion, CVRx, Cytokinetics, Intellia, and Rocket. Dr Abraham has received consulting fees from Boehringer Ingelheim, Cardionomic, Zoll Respicardia, scPharmaceuticals, Sensible Medical, and Vectorious; has received salary support from V-Wave Medical; and has served as a speaker for Edwards Lifesciences. Dr Lindenfeld has received consulting fees from Abbott, ADI, Alleviant, Amgen, AstraZeneca, Axon, Boston Scientific, Cordio, CVRx, Cytokinetics, Edwards Lifesciences, Medtronic, Merck, VWave, Vascular Dynamics, Vectorious, and Whiteswell; and has received grants from Analog Devices Inc, AstraZeneca, and Volumetrix. Dr DeMets has received consulting fees from the National Institutes of Health, the U.S. Food and Drug Administration, and the pharmaceutical and medical device industry on the design, monitoring, and analysis of clinical trials; and he has received compensation for serving on several recent industry-sponsored data and safety monitoring committees or steering committees including AstraZeneca, Bristol Meyers Squib, GSK, Merck, Boston Scientific, Medtronic, USONA, LivaNova, AnthosTherapy, ARCA biopharma, Duke Clinical Research Institute, and the Population Health Research Institute of Hamilton Ontario. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Both individually and cluster randomized study designs have been used for vaccine trials to assess the effects of vaccine on reducing the risk of disease or infection. The choice between individually and cluster randomized designs is often driven by the target estimand of interest (eg, direct versus total), statistical power, and, importantly, logistic feasibility. To combat emerging infectious disease threats, especially when the number of events from one single trial may not be adequate to obtain vaccine effect estimates with a desired level of precision, it may be necessary to combine information across multiple trials. In this article, we propose a model formulation to estimate the direct, indirect, total, and overall vaccine effects combining data from trials with two types of study designs: individual-randomization and cluster-randomization, based on a Cox proportional hazards model, where the hazard of infection depends on both vaccine status of the individual as well as the vaccine status of the other individuals in the same cluster. We illustrate the use of the proposed model and assess the potential efficiency gain from combining data from multiple trials, compared to using data from each individual trial alone, through two simulation studies, one of which is designed based on a cholera vaccine trial previously carried out in Matlab, Bangladesh., (© 2024 John Wiley & Sons Ltd.)

Background: Idiopathic pulmonary fibrosis (IPF) carries significant mortality and unpredictable progression, with limited therapeutic options. Designing trials with patient-meaningful endpoints, enhancing the reliability and interpretability of results, and streamlining the regulatory approval process are of critical importance to advancing clinical care in IPF. Methods: A landmark in-person symposium in June 2023 assembled 43 participants from the US and internationally, including patients with IPF, investigators, and regulatory representatives, to discuss the immediate future of IPF clinical trial endpoints. Patient advocates were central to discussions, which evaluated endpoints according to regulatory standards and the FDA's 'feels, functions, survives' criteria. Results: Three themes emerged: 1 ) consensus on endpoints mirroring the lived experiences of patients with IPF; 2 ) consideration of replacing forced vital capacity (FVC) as the primary endpoint, potentially by composite endpoints that include 'feels, functions, survives' measures or FVC as components; 3 ) support for simplified, user-friendly patient-reported outcomes (PROs) as either components of primary composite endpoints or key secondary endpoints, supplemented by functional tests as secondary endpoints and novel biomarkers as supportive measures (FDA Guidance for Industry (Multiple Endpoints in Clinical Trials) available at: https://www.fda.gov/media/162416/download). Conclusions: This report, detailing the proceedings of this pivotal symposium, suggests a potential turning point in designing future IPF clinical trials more attuned to outcomes meaningful to patients, and documents the collective agreement across multidisciplinary stakeholders on the importance of anchoring IPF trial endpoints on real patient experiences-namely, how they feel, function, and survive. There is considerable optimism that clinical care in IPF will progress through trials focused on patient-centric insights, ultimately guiding transformative treatment strategies to enhance patients' quality of life and survival.

Rapidly expanding systemic treatment options, combined with improved screening, diagnostic, surgical, and radiotherapy techniques, have led to improved survival outcomes for many cancers over time. However, these overall survival gains have disproportionately benefited patients in high-income countries, whereas patients in low- and middle-income countries (LMICs) continue to experience challenges in accessing timely and guideline concordant care. In September 2022, the Accelerating Anticancer Agent Development and Validation workshop was held, focusing on global cancer drug development. Panelists discussed key barriers such as the lack of diagnostic services and human resources, drug accessibility and affordability, lack of research infrastructure, and regulatory and authorization challenges, with a particular focus on Africa and Latin America. Potential opportunities to improve access and affordability were reviewed, such as the importance of prioritizing investments in diagnostics, investing health infrastructure and work force planning, coordinated drug procurement efforts and streamlined regulatory processing, incentivized pricing through regulatory change, and the importance of developing and promoting clinical trials that can answer relevant clinical questions for patients in LMICs. As a cancer community, we must continue to advocate for and work toward equitable access to high-quality interventions for patients, regardless of their geographical location.

An important element of precision medicine is the ability to identify, for a specific therapy, those patients for whom benefits of that therapy meaningfully exceed the risks. To achieve this goal, treatment effect usually is examined across subgroups defined by a variety of factors, including demographic, clinical, or pathologic characteristics or by molecular attributes of patients or their disease. Frequently such subgroups are defined by the measurement of biomarkers. Even though such examination is necessary when pursuing this goal, the evaluation of treatment effect across a variety of subgroups is statistically fraught due to both the danger of inflated false-positive error rate from multiple testing and the inherent insensitivity to how treatment effects differ across subgroups.Pre-specification of subgroup analyses with appropriate control of false-positive (i.e. type I) error is recommended when possible. However, when subgroups are specified by biomarkers, which could be measured by different assays and might lack established interpretation criteria, such as cut-offs, it might not be possible to fully specify those subgroups at the time a new therapy is ready for definitive evaluation in a Phase 3 trial. In these situations, further refinement and evaluation of treatment effect in biomarker-defined subgroups might have to take place within the trial. A common scenario is that evidence suggests that treatment effect is a monotone function of a biomarker value, but optimal cut-offs for therapy decisions are not known. In this setting, hierarchical testing strategies are widely used, where testing is first conducted in a particular biomarker-positive subgroup and then is conducted in the expanded pool of biomarker-positive and biomarker-negative patients, with control for multiple testing. A serious limitation of this approach is the logical inconsistency of excluding the biomarker-negatives when evaluating effects in the biomarker-positives, yet allowing the biomarker-positives to drive the assessment of whether a conclusion of benefit could be extrapolated to the biomarker-negative subgroup.Examples from oncology and cardiology are described to illustrate the challenges and pitfalls. Recommendations are provided for statistically valid and logically consistent subgroup testing in these scenarios as alternatives to reliance on hierarchical testing alone, and approaches for exploratory assessment of continuous biomarkers as treatment effect modifiers are discussed.

Even with recent substantive improvements in health care in pediatric populations, considerable need remains for additional safe and effective interventions for the prevention and treatment of diseases in children. The approval of prescription drugs and biological products for use in pediatric settings, as in adults, requires demonstration of substantial evidence of effectiveness and favorable benefit-to-risk. For diseases primarily affecting children, such evidence predominantly would be obtained in the pediatric setting. However, for conditions affecting both adults and children, pediatric extrapolation uses scientific evidence in adults to enable more efficiently obtaining a reliable evaluation of an intervention's effects in pediatric populations. Bridging biomarkers potentially have an integral role in pediatric extrapolation. In a setting where an intervention reliably has been established to be safe and effective in adults, and where there is substantive evidence that disease processes in pediatric and adult settings are biologically similar, a 'bridging biomarker' should satisfy three additional criteria: effects on the bridging biomarker should capture effects on the principal causal pathway through which the disease process meaningfully influences 'feels, functions, survives' measures; secondly, the experimental intervention should not have important unintended effects on 'feels, functions, survives' measures not captured by the bridging biomarker; and thirdly, in statistical analyses in adults, the intervention's net effect on 'feels, functions, survives' measures should be consistent with what would be predicted by its level of effect on the bridging biomarker. A validated bridging biomarker has considerable potential utility, since an intervention's efficacy could be extrapolated from adult to pediatric populations if evidence in children establishes the intervention not only to be safe but also to have substantive effects on that bridging biomarker. Proper use of bridging biomarkers could increase availability of reliably evaluated therapies approved for use in pediatric settings, enabling children and their caregivers to make informed choices about health care., (© 2022. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background/aims: The HIV Prevention Trials Network 083 trial was a group-sequential non-inferiority trial designed to compare HIV incidence under a novel experimental regimen for HIV prevention, long-acting injectable cabotegravir, with an active-control regimen of daily oral tenofovir disoproxil fumarate/emtricitabine (brand name Truvada). In March of 2020, just as the trial had completed enrollment, the COVID-19 pandemic threatened to prevent trial participants from attending study visits and obtaining study medication, motivating the study team to update the interim monitoring plan. The Data and Safety Monitoring Board subsequently stopped the trial at the first interim review due to strong early evidence of efficacy., Methods: Here we describe some unique aspects of the trial's design, monitoring, analysis, and interpretation. We illustrate the importance of computing point estimates, confidence intervals, and p values based on the sampling distribution induced by sequential monitoring., Results: Accurate analysis, decision-making and interpretation of trial results rely on pre-specification of a stopping boundary, including the scale on which the stopping rule will be implemented, the specific test statistics to be calculated, and how the boundary will be adjusted if the available information fraction at interim review is different from planned. After appropriate adjustment for the sampling distribution and overrun, the HIV Prevention Trials Network 083 trial provided strong evidence that the experimental regimen was superior to the active control., Conclusions: For the HIV Prevention Trials Network 083 trial, the difference between corrected inferential statistics and naive results was quite small-as will often be the case-nevertheless, it is appropriate to report and publish the most accurate and unbiased statistical results.

Background: The threat of a possible Marburg virus disease outbreak in Central and Western Africa is growing. While no Marburg virus vaccines are currently available for use, several candidates are in the pipeline. Building on knowledge and experiences in the designs of vaccine efficacy trials against other pathogens, including SARS-CoV-2, we develop designs of randomized Phase 3 vaccine efficacy trials for Marburg virus vaccines., Methods: A core protocol approach will be used, allowing multiple vaccine candidates to be tested against controls. The primary objective of the trial will be to evaluate the effect of each vaccine on the rate of virologically confirmed Marburg virus disease, although Marburg infection assessed via seroconversion could be the primary objective in some cases. The overall trial design will be a mixture of individually and cluster-randomized designs, with individual randomization done whenever possible. Clusters will consist of either contacts and contacts of contacts of index cases, that is, ring vaccination, or other transmission units., Results: The primary efficacy endpoint will be analysed as a time-to-event outcome. A vaccine will be considered successful if its estimated efficacy is greater than 50% and has sufficient precision to rule out that true efficacy is less than 30%. This will require approximately 150 total endpoints, that is, cases of confirmed Marburg virus disease, per vaccine/comparator combination. Interim analyses will be conducted after 50 and after 100 events. Statistical analysis of the trial will be blended across the different types of designs. Under the assumption of a 6-month attack rate of 1% of the participants in the placebo arm for both the individually and cluster-randomized populations, the most likely sample size is about 20,000 participants per arm., Conclusion: This event-driven design takes into the account the potentially sporadic spread of Marburg virus. The proposed trial design may be applicable for other pathogens against which effective vaccines are not yet available.

Decision making about vaccination and boosting schedules for coronavirus disease 2019 (COVID-19) hinges on reliable methods for evaluating the longevity of vaccine protection. We show that modeling of protection as a piecewise linear function of time since vaccination for the log hazard ratio of the vaccine effect provides more reliable estimates of vaccine effectiveness at the end of an observation period and also detects plateaus in protective effectiveness more reliably than the standard method of estimating a constant vaccine effect over each time period. This approach will be useful for analyzing data pertaining to COVID-19 vaccines and other vaccines for which rapid and reliable understanding of vaccine effectiveness over time is desired., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The emergence of Marburg virus (MARV) in Guinea and Ghana triggered the assembly of the MARV vaccine "MARVAC" consortium representing leaders in the field of vaccine research and development aiming to facilitate a rapid response to this infectious disease threat. Here, we discuss current progress, challenges, and future directions for MARV vaccines., Competing Interests: T.W.G. holds U.S. patent number 7,635,485 issued to US Government, U.S. patent number 7,838,658 issued to Arbutus Biopharma, U.S. patent number 8,017,130 issued to US Government, U.S. patent number 8,716,464 issued to Arbutus Biopharma, and U.S. patent number 8,796,013 issued to Boston University. N.J.S. has a patent for Chimpanzee Adenoviral vector-based filovirus vaccines (for use in humans) with royalties paid to GlaxoSmithKline Biologicals. K.L.W. is a stockholder of Emergent BioSolutions. R.Z. holds a patent for “Methods and compositions for inducing protective immunity against Marburg virus infection”. All other authors declare no conflict of interest. The conclusions in this report are those of the authors and do not necessarily represent the official position of the U.S. Centers for Disease Control and Prevention.

Objective: To summarize proceedings of a workshop convened to discuss the current state of science in the disease of osteoarthritis (OA), identify the knowledge gaps, and examine the developmental and regulatory challenges in bringing these products to market., Design: Summary of the one-day workshop held virtually on June 22nd, 2021., Results: Speakers selected by the Planning Committee presented data on the current approach to assessment of OA therapies, biomarkers in OA drug development, and the assessment of disease progression and long-term benefit., Conclusions: Demonstrated by numerous failed clinical trials, OA is a challenging disease for which to develop therapeutics. The challenge is magnified by the slow time of onset of disease and the need for clinical trials of long duration and/or large sample size to demonstrate the effect of an intervention. The OA science community, including academia, pharmaceutical companies, regulatory agencies, and patient communities, must continue to develop and test better clinical endpoints that meaningfully reflect disease modification related to long-term patient benefit., Competing Interests: Declaration of Competing Interest One or more of the authors has received or will receive benefits for personal or professional use from a commercial party related directly or indirectly to the subject of this article., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: CDKL5 deficiency disorder (CDD) is a rare, X-linked, developmental and epileptic encephalopathy characterised by severe global developmental impairment and seizures that can begin in the first few months after birth and are often treatment refractory. Ganaxolone, an investigational neuroactive steroid, reduced seizure frequency in an open-label, phase 2 trial that included patients with CDD. We aimed to further assess the efficacy and safety of ganaxolone in patients with CDD-associated refractory epilepsy., Methods: In the double-blind phase of this randomised, placebo-controlled, phase 3 trial, done at 39 outpatient clinics in eight countries (Australia, France, Israel, Italy, Poland, Russia, the UK, and the USA), patients were eligible if they were aged 2-21 years with a pathogenic or probably pathogenic CDKL5 variant and at least 16 major motor seizures (defined as bilateral tonic, generalised tonic-clonic, bilateral clonic, atonic, or focal to bilateral tonic-clonic) per 28 days in each 4-week period of an 8-week historical period. After a 6-week prospective baseline period, patients were randomly assigned (1:1) via an interactive web response system to receive either enteral adjunctive ganaxolone or matching enteral adjunctive placebo (maximum dose 63 mg/kg per day for patients weighing ≤28 kg or 1800 mg/day for patients weighing >28 kg) for 17 weeks. Patients, caregivers, investigators (including those analysing data), trial staff, and the sponsor (other than the investigational product manager) were masked to treatment allocation. The primary efficacy endpoint was percentage change in median 28-day major motor seizure frequency from the baseline period to the 17-week double-blind phase and was analysed (using a Wilcoxon-rank sum test) in all patients who received at least one dose of trial treatment and for whom baseline data were available. Safety (compared descriptively across groups) was analysed in all patients who received at least one dose of trial treatment. This study is registered with ClinicalTrials.gov, NCT03572933, and the open-label extension phase is ongoing., Findings: Between June 25, 2018, and July 2, 2020, 114 patients were screened for eligibility, of whom 101 (median age 6 years [IQR 3 to 10]) were randomly assigned to receive either ganaxolone (n=50) or placebo (n=51). All patients received at least one dose of a study drug, but seizure frequency for one patient in the ganaxolone group was not recorded at baseline and so the primary endpoint was analysed in a population of 100 patients. There was a median percentage change in 28-day major motor seizure frequency of -30·7% (IQR -49·5 to -1·9) in the ganaxolone group and of -6·9% (-24·1 to 39·7) in the placebo group (p=0·0036). The Hodges-Lehmann estimate of median difference in responses to ganaxolone versus placebo was -27·1% (95% CI -47·9 to - 9·6). Treatment-emergent adverse events occurred in 43 (86%) of 50 patients in the ganaxolone group and in 45 (88%) of 51 patients in the placebo group. Somnolence, pyrexia, and upper respiratory tract infections occurred in at least 10% of patients in the ganaxolone group and more frequently than in the placebo group. Serious adverse events occurred in six (12%) patients in the ganaxolone group and in five (10%) patients in the placebo group. Two (4%) patients in the ganaxolone group and four (8%) patients in the placebo group discontinued the trial. There were no deaths in the double-blind phase., Interpretation: Ganaxolone significantly reduced the frequency of CDD-associated seizures compared with placebo and was generally well tolerated. Results from what is, to our knowledge, the first controlled trial in CDD suggest a potential treatment benefit for ganaxolone. Long-term treatment is being assessed in the ongoing open-label extension phase of this trial., Funding: Marinus Pharmaceuticals., Competing Interests: Declaration of interests EMPK has consulted for Marinus Pharmaceuticals, had no consulting relationship with Marinus Pharmaceuticals until after the completion of the double-blind phase of the current trial, and has participated in advisory boards for BioMarin and Zogenix. SA has received funding from GW Pharmaceuticals, Novartis, PTC Therapeutics, Boston Scientific, Nutricia, UCB, BioMarin, LivaNova, Medtronic, Desitin, Ipsen, CDKL5 UK, TSA, and the National Institute for Health Research. NB-B has consulted for Roche, LivaNova, and PTC Therapeutics, and has received funding from GW Pharmaceuticals. TAB has consulted for Taysha, Alcyone, Novartis/AveXis, Ovid, GW Pharmaceuticals, the International Rett Syndrome Foundation, Takeda, Ultragenyx, and Marinus Pharmaceuticals; has participated in clinical trials with Acadia, Ovid, GW Pharmaceuticals, Marinus Pharmaceuticals, and the Rett Syndrome Research Trust; and has received research funding from the National Institutes of Health, the International Foundation for CDKL5 Research, Rocky Mountain Rett Association, the GRIN2B Foundation, and Mallinckrodt (all remuneration has been made to his department). JHC has acted as an investigator for studies with GW Pharmaceuticals, Stoke Therapeutics, Ovid, Zogenix, and Vitaflo and for the current trial with Marinus Pharmaceuticals; has been a speaker and participated on advisory boards for Zogenix, Biocodex, UCB, and Nutricia (all remuneration has been paid to her department); holds an endowed chair at University College London Great Ormond Street Institute of Child Health (London, UK); and declares grants from the National Institute for Health Research, the Engineering and Physical Sciences Research Council, Great Ormond Street Hospital Children's Charity, Epilepsy Research United Kingdom, the Waterloo Foundation, and the National Institute of Health Research Biomedical Research Centre at Great Ormond Street Hospital. STD has consulted for Taysha, Neurogene, Ovid, and Marinus Pharmaceuticals; has received speaker honoraria from BioMarin and Marinus Pharmaceuticals; has received funding from the National Institutes of Health, the International Foundation for CDKL5 Research, and Mila's Miracle Foundation; and serves on advisory boards for the non-profit foundations SLC6A1 Connect, FamilieSCN2A, and Ring 14 USA. HEO has consulted for Takeda, Ovid, Zogenix, the FOXG1 Research Foundation, and Marinus Pharmaceuticals; has served as site principal investigator for a trial with Ovid and for the current trial with Marinus Pharmaceuticals; and has funding from the National Institute of Neurological Disorders and Stroke, the Loulou Foundation, the Manton Center for Rare Disease Research, and the International Foundation for CDKL5 Research for research on CDD. NS has served on scientific advisory boards for GW Pharmaceuticals, BioMarin, Arvelle, Takeda, and Marinus Pharmaceuticals; has received speaker honoraria from Eisai, BioMarin, LivaNova, and Sanofi; has served as an investigator for Zogenix, BioMarin, UCB, Roche, and Marinus Pharmaceuticals; and has received support for attending meetings from LivaNova. TRF received consulting fees from Marinus Pharmaceuticals for service on the scientific steering committee overseeing the design, conduct, and analysis of trials of ganaxolone in CDKL5-deficient epileptic encephalopathy and in protocadherin-19-related epilepsy. AAA is a salaried employee of Marinus Pharmaceuticals and owns stock in the company. MG is a salaried employee of Marinus Pharmaceuticals and owns stock in the company. OD receives grant support from the National Institute of Neurological Disorders and Stroke, the National Institute of Mental Health, the Multidisciplinary University Research Initiative, the Centers for Disease Control and Prevention, and the National Science Foundation; has equity, compensation, or both from Tilray, Receptor Life Sciences, Q-State Biosciences, Tevard, Empatica, Papa & Barkley, Rettco, Silver Spike, and California Cannabis Enterprises; has received consulting fees from GW Pharmaceuticals, BridgeBio, Ultragenyx, Xenon, and Marinus Pharmaceuticals; has received honoraria from Medscape; has multiple patents for the use of cannabis but all financial benefits have been waived; has received royalties for the book Epilepsy in Children; and serves on the boards of FACES and Next for Autism., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of interests We declare no competing interests.

Multiple candidate vaccines to prevent COVID-19 have entered large-scale phase 3 placebo-controlled randomized clinical trials, and several have demonstrated substantial short-term efficacy. At some point after demonstration of substantial efficacy, placebo recipients should be offered the efficacious vaccine from their trial, which will occur before longer-term efficacy and safety are known. The absence of a placebo group could compromise assessment of longer-term vaccine effects. However, by continuing follow-up after vaccination of the placebo group, this study shows that placebo-controlled vaccine efficacy can be mathematically derived by assuming that the benefit of vaccination over time has the same profile for the original vaccine recipients and the original placebo recipients after their vaccination. Although this derivation provides less precise estimates than would be obtained by a standard trial where the placebo group remains unvaccinated, this proposed approach allows estimation of longer-term effect, including durability of vaccine efficacy and whether the vaccine eventually becomes harmful for some. Deferred vaccination, if done open-label, may lead to riskier behavior in the unblinded original vaccine group, confounding estimates of long-term vaccine efficacy. Hence, deferred vaccination via blinded crossover, where the vaccine group receives placebo and vice versa, would be the preferred way to assess vaccine durability and potential delayed harm. Deferred vaccination allows placebo recipients timely access to the vaccine when it would no longer be proper to maintain them on placebo, yet still allows important insights about immunologic and clinical effectiveness over time.

Background: Although several COVID-19 vaccines have been found to be effective in rigorous evaluation and have emerging availability in parts of the world, their supply will be inadequate to meet international needs for a considerable period of time. There also will be continued interest in vaccines that are more effective or have improved scalability to facilitate mass vaccination campaigns. Ongoing clinical testing of new vaccines also will be needed as variant strains continue to emerge that may elude some aspects of immunity induced by current vaccines. Randomized clinical trials meaningfully enhance the efficiency and reliability of such clinical testing. In clinical settings with limited or no access to known effective vaccines, placebo-controlled randomized trials of new vaccines remain a preferred approach to maximize the reliability, efficiency and interpretability of results. When emerging availability of licensed vaccines makes it no longer possible to use a placebo control, randomized active comparator non-inferiority trials may enable reliable insights., Methods: In this article, "hybrid" methods are proposed to address settings where, during the conduct of a placebo-controlled trial, a judgment is made to replace the placebo arm by a licensed COVID-19 vaccine due to emerging availability of effective vaccines in regions participating in that trial. These hybrid methods are based on proposed statistics that aggregate evidence to formally test as well as to estimate the efficacy of the experimental vaccine, by combining placebo-controlled data during the first period of trial conduct with active-controlled data during the second period., Results: Application of the proposed methods is illustrated in two important scenarios where the active control vaccine would become available in regions engaging in the experimental vaccine's placebo-controlled trial: in the first, the active comparator's vaccine efficacy would have been established to be 50%-70% for the 4- to 6-month duration of follow-up of its placebo-controlled trial; in the second, the active comparator's vaccine efficacy would have been established to be 90%-95% during that duration. These two scenarios approximate what has been seen with adenovirus vaccines or mRNA vaccines, respectively, assuming the early estimates of vaccine efficacy for those vaccines would hold over longer-term follow-up., Conclusion: The proposed hybrid methods could readily play an important role in the near future in the design, conduct and analysis of randomized clinical trials performed to address the need for multiple additional vaccines reliably established to be safe and have worthwhile efficacy in reducing the risk of symptomatic disease from SARS-CoV-2 infections.

Viral variants of concern may emerge with dangerous resistance to the immunity generated by the current vaccines to prevent coronavirus disease 2019 (Covid-19). Moreover, if some variants of concern have increased transmissibility or virulence, the importance of efficient public health measures and vaccination programs will increase. The global response must be both timely and science based., (Copyright © 2021 Massachusetts Medical Society.)

Background: Recently emerging results from a few placebo-controlled randomized trials of COVID-19 vaccines revealed estimates of 62%-95% relative reductions in risk of virologically confirmed symptomatic COVID-19 disease, over approximately 2-month average follow-up period. Additional safe and effective COVID-19 vaccines are needed in a timely manner to adequately address the pandemic on an international scale. Such safe and effective vaccines would be especially appealing for international deployment if they also have favorable stability, supply, and potential for implementation in mass vaccination campaigns. Randomized trials provide particularly reliable insights about vaccine efficacy and safety. While enhanced efficiency and interpretability can be obtained from placebo-controlled trials, in settings where their conduct is no longer possible, randomized non-inferiority trials may enable obtaining reliable evaluations of experimental vaccines through direct comparison with active comparator vaccines established to have worthwhile efficacy., Methods: The usual objective of non-inferiority trials is to reliably assess whether the efficacy of an experimental vaccine is not unacceptably worse than that of an active control vaccine previously established to be effective, likely in a placebo-controlled trial. This is formally achieved by ruling out a non-inferiority margin identified to be the minimum threshold for what would constitute an unacceptable loss of efficacy. This article not only investigates non-inferiority margins, denoted by δ , that address the usual objective of determining whether the experimental vaccine is "at least similarly effective to" the active comparator vaccine in the non-inferiority trial, but also develops non-inferiority margins, denoted by δ o , intended to address the worldwide need for multiple safe and effective vaccines by satisfying the less stringent requirement that the experimental vaccine be "at least similarly effective to" an active comparator vaccine having efficacy that satisfies the widely accepted World Health Organization-Food and Drug Administration criteria for "worthwhile" vaccine efficacy., Results: Using the margin δ enables non-inferiority trials to reliably evaluate experimental vaccines that truly are similarly effective to an active comparator vaccine having any level of "worthwhile" efficacy. When active comparator vaccines have efficacy in the range of 50%-70%, non-inferiority trials designed to use the margin δ o have appealing properties, especially for experimental vaccines having true efficacy of approximately 60%., Conclusion: Non-inferiority trials using the proposed margins may enable reliable randomized evaluations of efficacy and safety of experimental COVID-19 vaccines. Such trials often require approximately two- to three-fold the person-years follow-up than a placebo-controlled trial. This could be achieved, without substantive increases in sample size, by increasing the average duration of follow-up from 2 months to approximately 4-6 months, assuming efficacy of the active comparator vaccine has been reliably evaluated over that longer duration.

Several vaccine candidates to protect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or coronavirus disease 2019 (COVID-19) have entered or will soon enter large-scale, phase 3, placebo-controlled randomized clinical trials. To facilitate harmonized evaluation and comparison of the efficacy of these vaccines, a general set of clinical endpoints is proposed, along with considerations to guide the selection of the primary endpoints on the basis of clinical and statistical reasoning. The plausibility that vaccine protection against symptomatic COVID-19 could be accompanied by a shift toward more SARS-CoV-2 infections that are asymptomatic is highlighted, as well as the potential implications of such a shift.

Best practices of data monitoring committees (DMCs) in randomized clinical trials are well established. Independent oversight provided by DMCs is particularly important in trials conducted in public health emergencies, such as in HIV/AIDS or coronavirus epidemics. Special considerations are needed to enable DMCs to effectively address novel circumstances they face in such settings. In the COVID-19 pandemic, these include the remarkable speed in which data regarding benefits and risks of interventions are accumulated. DMCs must hold frequent virtual meetings, using state-of-the-art communication software that protects against risk for security breaches. Data capture and DMC reports should be focused on the most informative measures about benefits and risks. Because numerous clinical trials are being concurrently conducted in the COVID-19 setting, often addressing closely related scientific questions, structures for DMC oversight should be efficient and adequately informative. When these concurrently conducted trials are evaluating related regimens in related clinical settings, often individually underpowered for safety and having separate DMCs, processes should be implemented enabling these DMCs to share with each other emerging confidential evidence to better assess risks and benefits. Ideally a single DMC would monitor a portfolio of clinical trials or a trial with multiple arms, such as a platform trial., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Combination HIV prevention approaches that include both biomedical and non-biomedical interventions often hold greater promise to improve health outcomes and reduce the risk of HIV transmission., Objectives: Evaluate the relative properties of four leading candidate trial designs - 'single-factor', 'multi-arm', 'all-in-one', and 'factorial' designs - for assessing individual and/or combination prevention intervention approaches., Methods: Monte-Carlo simulations are conducted, assuming a putative combination approach could choose its components from two candidate biomedical interventions, i.e. Treatment-as-Prevention (TasP) and Pre-exposure Prophylaxis (PrEP), and three candidate behavioral interventions, i.e. linkage-to-care, counseling, and use of condoms. Various scenarios for individual components' effect sizes, their possible interaction, and the sample size based on real clinical studies are considered., Results: The all-in-one and factorial designs used to assess a combination approach and the multi-arm design used to assess multiple individual components are consistently more powerful than single-factor designs. The all-in-one design is powerful when the individual components are effective without negative interaction, while the factorial design is more consistently powerful across a broad array of settings., Conclusions: The multi-arm design is useful for evaluating single factor regimens, while the all-in-one and factorial designs are sensitive in assessing the overall efficacy when there is interest in combining individual component regimens anticipated to have complementary mechanisms. The factorial design is a preferred approach when assessing combination regimens due to its favorable power properties and since it is the only design providing direct insights about the contribution of individual components to the combination approach's overall efficacy and about potential interactions.