Outcome measures in inflammatory rheumatic diseases

Inflammatory rheumatic diseases are generally multifaceted disorders and, therefore, measurement of multiple outcomes is relevant to most of these diseases. Developments in outcome measures in the rheumatic diseases are promoted by the development of successful treatments. Outcome measurement will increasingly deal with measurement of low levels of disease activity and avoidance of disease consequences. It is an advantage for patient management and knowledge transfer if the same outcomes are used in practice and in trials. Continuous measures of change are generally the most powerful and, therefore, are preferred as primary outcomes in trials. For daily clinical practice, outcome measures should reflect the patients' state and have to be easily derivable. The objective of this review is to describe recent developments in outcome measures for inflammatory rheumatic diseases for trials and clinical practice, with an emphasis on rheumatoid arthritis.     

Clinical trials in systemic sclerosis: lessons learned and outcomes

The pathogenesis of systemic sclerosis (SSc) is complex and largely unclear. The clinical heterogeneity of the disease and its progression over a number of years makes the choice of endpoints in the design of clinical trials difficult. The overwhelming need in this disease is to diagnose it early and identify those patients who will benefit most from early, aggressive treatment that potentially can alter the clinical disease course. To achieve this, innumerable challenges must be overcome. This article reviews data from recent clinical trials and the lessons derived from retrospective observational studies, databases, and patient registries. Taken together, these observations will help to improve our understanding of the diverse clinical course of SSc and permit refinement of existing outcome measures for the design of future clinical trials, in which the likelihood of observing a positive treatment effect with the drugs at our disposal will be maximized.     

Clinical outcomes and outcome measurement tools reported in randomised controlled trials of treatment for snakebite envenoming: A systematic review

BackgroundSnakebite is a priority neglected tropical disease and causes a range of complications that vary depending on the snake species. Randomised clinical trials have used varied outcome measures that do not allow results to be compared or combined. In accordance with the Core Outcomes Measurements in Effectiveness Trials (COMET) initiative, this systematic review aims to support the development of a globally relevant core outcome set for snakebite.MethodsAll randomised controlled trials, secondary analyses of randomised controlled trials and study protocols investigating the efficacy of therapeutics for human snakebite envenoming were eligible for inclusion. Study screening and data extraction were conducted in duplicate by two independent reviewers. All primary and secondary outcome measures were extracted and compiled, as were adverse event outcome measures. Similar outcome measures were grouped into domains. The study was prospectively registered with PROSPERO: CRD42020196160.ResultsThis systematic review included 43 randomised controlled trials, two secondary analyses and 13 study protocols. A total of 382 outcome measures were extracted and, after duplicates were merged, there were 153 unique outcomes. The most frequently used outcome domain (‘venom antigenaemia’) was included in less than one third of the studies. The unique outcomes were classified into 60 outcome domains. Patient-centred outcomes were used in only three of the studies.DiscussionSignificant heterogeneity in outcome measures exists in snakebite clinical trials. Consensus is needed to select outcome measures that are valid, reliable, patient-centred and feasible. The results of this systematic review strongly support the development of a core outcome set for use in snakebite clinical trials.     

Inference in response-adaptive clinical trials when the enrolled population varies over time

A common assumption of data analysis in clinical trials is that the patient population, as well as treatment effects, do not vary during the course of the study. However, when trials enroll patients over several years, this hypothesis may be violated. Ignoring variations of the outcome distributions over time, under the control and experimental treatments, can lead to biased treatment effect estimates and poor control of false positive results. We propose and compare two procedures that account for possible variations of the outcome distributions over time, to correct treatment effect estimates, and to control type-I error rates. The first procedure models trends of patient outcomes with splines. The second leverages conditional inference principles, which have been introduced to analyze randomized trials when patient prognostic profiles are unbalanced across arms. These two procedures are applicable in response-adaptive clinical trials. We illustrate the consequences of trends in the outcome distributions in response-adaptive designs and in platform trials, and investigate the proposed methods in the analysis of a glioblastoma study.     

Henoch schonlein purpura--a 5-year review and proposed pathway

Henoch Schonlein Purpura (HSP) is the commonest systemic vasculitis of childhood typically presenting with a palpable purpuric rash and frequently involving the renal system. We are the first group to clinically assess, critically analyse and subsequently revise a nurse led monitoring pathway for this condition.A cohort of 102 children presenting with HSP to a secondary/tertiary level UK paediatric hospital over a five year period, were monitored using a nurse led care pathway. Using this cohort, the incidence (6.21 cases per 100,000 children per year) and natural disease course of HSP nephritis (46% initial renal inflammation; 9% subsequent renal referral; 1% renal biopsy and immunosuppression) was determined. Older patients were at higher risk of requiring a renal referral (renal referral 12.3 (8.4-13.5) years vs. normal outcome 6.0 (3.7-8.5) years; p<0.01). A normal urinalysis on day 7 had a 97% (confidence interval 90 to 99%) negative predictive value in predicting a normal renal outcome.Using this data and existing literature base, The Alder Hey Henoch Schonlein Purpura Pathway was developed, a revised pathway for the screening of poor renal outcome in HSP. This is based on a six-month monitoring period for all patients presenting with HSP, which importantly prioritises patients according to the urine findings on day 7 and thus intensively monitors those at higher risk of developing nephritis. The pathway could be easily adapted for use in different settings and resources.The introduction of a standardised pathway for the monitoring of HSP will facilitate the implementation of disease registries to further our understanding of the condition and permit future clinical trials.     

Proteomics and ovarian cancer: Integrating proteomics information into clinical care

The power of proteomics allows unparalleled opportunity to query the molecular mechanisms of a malignant cell and the tumor microenvironment in patients with ovarian cancer and other solid tumors. This information has given us insight into the perturbations of signaling pathways within tumor cells and has aided the discovery of new drug targets for the tumor and possible prognostic indicators of outcome and disease response to therapy. Proteomics analysis of serum and ascites has also given us sources with which to discover possible early markers for the presence of new disease and for the progression of established cancer throughout the course of treatment. Unfortunately, this wealth of information has yielded little to date in changing the clinical care of these patients from a diagnostic, prognostic, or treatment perspective. The rational examination and translation of proteomics data in the context of past clinical trials and the design of future clinical trials must occur before we can march forward into the future of personalized medicine.     

Design of a multicentre randomized trial to evaluate CT colonography versus colonoscopy or barium enema for diagnosis of colonic cancer in older symptomatic patients: The SIGGAR study

Clinical trials on novel drug therapies require clear criteria for patient selection and agreed definitions of disease remission. This principle has been successfully applied in the field of rheumatology where agreed disease scoring systems have allowed multi-centre collaborations and facilitated audit across treatment centres. Unfortunately in ulcerative colitis this consensus is lacking. Thirteen scoring systems have been developed but none have been properly validated. Most trials choose different endpoints and activity indices, making comparison of results from different trials extremely difficult. International consensus on endoscopic, clinical and histological scoring systems is essential as these are the key components used to determine entry criteria and outcome measurements in clinical trials on ulcerative colitis. With multiple new therapies under development, there is a pressing need for consensus to be reached.     

Self-help materials for the prevention of smoking relapse: study protocol for a randomized controlled trial

Background

In clinical trials in childhood asthma, outcomes reflecting short-term disease activity are frequently measured, whilst functional status, quality of life (QoL), and long-term treatment effects are rarely assessed. There is also non-uniformity across studies in the selection and measurement of outcomes within these domains. The development of a core outcome set has the potential to reduce heterogeneity between trials, lead to research that is more likely to have measured relevant outcomes, and enhance the value of evidence synthesis by reducing the risk of outcome reporting bias and ensuring that all trials contribute usable information.

Methods

Paediatricians and specialist nurses, identified through the British Paediatric Respiratory Society, completed a two-round Delphi survey. Separate cohorts of parents of children younger than 18?years, recruited in clinics, participated in each round. Young people with asthma, aged at least 13?years, participated in the first round. Outcomes were identified separately for preschool and school-aged children. We identified outcomes considered important in routine clinical assessment by clinicians and parents/young people. In round 1, 46 clinicians suggested outcomes they considered important when deciding whether to adjust a child??s asthma therapy regime, and 49 parents/young people were asked, using open questions, how they judged whether their child??s (for young people, their own) asthma therapy was appropriate. Two researchers independently classified responses into appropriate, corresponding outcomes. In round 2, 43 clinicians and 50 parents scored, from 0?C4, the importance of each outcome suggested by at least 10?% of round 1 responders and selected the three most important.

Results

The most important outcomes, when making shared decisions about regular therapies for school-aged and preschool children with asthma, were daytime and nocturnal symptoms, exacerbations, QoL, and mortality. Results from parents and clinicians were generally concordant, but parents placed more emphasis on long-term treatment effects.

Conclusions

We have developed a methodology to identify outcomes of most relevance to clinicians, parents, and young people when evaluating regularly administered therapies for asthma. Daytime and nocturnal symptoms, exacerbations, QoL, and mortality are particularly important outcomes that should be measured and reported in all clinical trials of regular therapies for children with asthma.     

The use of actigraphy in the monitoring of methylphenidate versus placebo in ADHD: a meta-analysis

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood. There is an increasing need to find objective measures and markers of the disorder in order to assess the efficacy of the therapy and to improve follow-up strategies. Actigraphy is an objective method for recording motor activity and sleep parameters using small, computerized, watch-like devices worn on the body, and it has been used in many clinical trials to assess methylphenidate efficacy and adverse effects in ADHD. Our article aim is to systematically review and perform a meta-analysis of the current evidence on the role of actigraphy in both the detection of changes in activity and in sleep patterns in randomized clinical trials that compared methylphenidate against placebo in the treatment of ADHD. A comprehensive literature search of PubMed/MEDLINE, Scopus, Embase, Cochrane Library, CINHAL and PsycINFO databases was carried out to find randomized clinical trials comparing methylphenidate versus placebo in children with ADHD, using actigraphic measures as an outcome. No start date limit was used and the search was updated until June 2013. The primary outcome measures were ‘total sleep time’ and daytime ‘activity mean’. As secondary outcomes, we analyzed ‘sleep onset latency’, ‘sleep efficiency’ and ‘wake after sleep onset’. Eight articles comprising 393 patients were included in the analysis. Children with ADHD using MPH compared to placebo have a significant difference of a large effect with a diminishing value in the activity mean. For the total sleep time, we found a significant and large effect in the decrease in sleep in MPH group. This study shows that MPH may effectively reduce mean activity in ADHD children, but it may negatively affect total sleep time.     

Differentiating the pathologies of cerebral malaria by postmortem parasite counts

To study the pathogenesis of fatal cerebral malaria, we conducted autopsies in 31 children with this clinical diagnosis. We found that 23% of the children had actually died from other causes. The remaining patients had parasites sequestered in cerebral capillaries, and 75% of those had additional intra- and perivascular pathology. Retinopathy was the only clinical sign distinguishing malarial from nonmalarial coma. These data have implications for treating malaria patients, designing clinical trials and assessing malaria-specific disease associations.     

A statistical framework for quantile equivalence clinical trials with application to pharmacokinetic studies that bridge from HIV-infected adults to children

SUMMARY: Bridging clinical trials are sometimes designed to evaluate whether a proposed dose for use in one population, for example, children, gives similar pharmacokinetic (PK) levels, or has similar effects on a surrogate marker as an established effective dose used in another population, for example, adults. For HIV bridging trials, because of the increased risk of viral resistance to drugs at low PK levels, the goal is often to determine whether the doses used in different populations result in similar percentages of patients with low PK levels. For example, it may be desired to evaluate that a proposed pediatric dose gives approximately 10% of children with PK levels below the 10th percentile of PK levels for the established adult dose. However, the 10th percentile for the adult dose is often imprecisely estimated in studies of relatively small size. Little attention has been given to the statistical framework for such bridging studies. In this article, a formal framework for the design and analysis of quantile-based bridging studies is proposed. The methodology is then developed for normally distributed outcome measures from both frequentist and Bayesian directions. Sample size and other design considerations are discussed.     

Comparison of design strategies for a three‐arm clinical trial with time‐to‐event endpoint: Power,time‐to‐analysis,and operational aspects

To optimize resources, randomized clinical trials with multiple arms can be an attractive option to simultaneously test various treatment regimens in pharmaceutical drug development. The motivation for this work was the successful conduct and positive final outcome of a three‐arm randomized clinical trial primarily assessing whether obinutuzumab plus chlorambucil in patients with chronic lympocytic lymphoma and coexisting conditions is superior to chlorambucil alone based on a time‐to‐event endpoint. The inference strategy of this trial was based on a closed testing procedure. We compare this strategy to three potential alternatives to run a three‐arm clinical trial with a time‐to‐event endpoint. The primary goal is to quantify the differences between these strategies in terms of the time it takes until the first analysis and thus potential approval of a new drug, number of required events, and power. Operational aspects of implementing the various strategies are discussed. In conclusion, using a closed testing procedure results in the shortest time to the first analysis with a minimal loss in power. Therefore, closed testing procedures should be part of the statistician's standard clinical trials toolbox when planning multiarm clinical trials.     

Progress in clinical trials for coronary arterial restenosis using beta radiation sources

Vascular brachytherapy has yet taken the leap into progression from emerging technology to standard of care dependent on the outcome of clinical trials. Data collected from early pilot trials and on-going clinical trials indicate that such a progression is achievable. Three-year follow-up data from patients treated with intracoronary radiation for the prevention of restenosis are now available. Data from larger trials are being assessed using angiographic and intravascular ultrasound analysis. The beta radiation studies are demonstrating different levels of efficacy, raising new issues regarding dosimetry and potential complications. Past trials have examined the use of vascular brachytherapy for recurrence prevention of restenosis in patients with in-stent restenosis. New data related to the use of liquid-filled balloon systems and radioactive stent are also being collected. This article updates the current status of clinical trials in vascular brachytherapy utilizing beta emitters, highlighting preliminary results and assessing their implications for the development of this field.     

Role of steroids and immunosuppression and effects of interferon beta-1b in multiple sclerosis.

Corticosteroids, corticotropin, azathioprine, cyclophosphamide, and IFN-beta 1b have each had a substantial effect on the care of patients with multiple sclerosis and the design of subsequent clinical trials of experimental therapeutics for MS. The use of MRI scanning and more sensitive clinical outcome measures will possibly enable us to complete clinical trials in a fraction of the time required for earlier trials. The release of Betaseron, which favorably alters the attack rate in ambulatory patients with relapsing-remitting MS has brought a sense of renewed optimism to patients with MS, their families, and their care providers. New promising therapies for chronic progressive MS and biologic products possibly capable of enhancing the effects of IFN-beta 1b in patients with relapsing MS are setting the stage for additional important therapeutic advances in this disease.     

Use of biomarkers in clinical trials of Alzheimer disease: from concept to application

Research progress during the last decades has resulted in an unprecedented accumulation of knowledge regarding the molecular pathogenesis of Alzheimer disease (AD). These important achievements toward clarifying the mechanistic processes underlying AD are being translated into ongoing development of biomarkers and their use in clinical trials. AD biomarkers are biochemical and anatomical variables (e.g. cerebrospinal fluid, positron emission tomography, and structural MRI) that measure AD-related pathologic features (i.e. amyloid deposition and neurodegeneration) in vivo. Biomarkers are utilized as 'diagnostic biomarkers' and/or 'endpoint biomarkers' in symptomatic or disease-modifying clinical trials. Diagnostic biomarkers play an important role in population enrichment by refining selection criteria, stratifying populations, and increasing the statistical power of trials. Endpoint biomarkers may be used as outcome measures to monitor the rate of disease progression and detect treatment effects. AD biomarkers do not reach abnormal levels or peak simultaneously, but do so in a time-dependent order. The choice of biomarkers for a clinical trial must take into consideration the type of therapeutic intervention, the clinical stage of AD, and the time dependence of biomarker changes during disease progression. The combination of amyloid and neurodegeneration biomarkers is highly desirable since they capture different aspects of the disease. Clinical trials for every clinical stage of AD would benefit from quantification and standardization of biomarkers. However, this is still a work in progress.     

Development of outcome measures according to dystrophic phenotypes in canine X-linked muscular dystrophy in Japan

Duchenne muscular dystrophy (DMD) is an X-linked lethal muscle disorder characterized by primary muscle degeneration. Therapeutic strategies for DMD have been extensively explored, and some are in the stage of human clinical trials. Along with the development of new therapies, sensitive outcome measures are needed to monitor the effects of new treatments. Therefore, we investigated outcome measures such as biomarkers and motor function evaluation in a dystrophic model of beagle dogs, canine X-linked muscular dystrophy in Japan (CXMD_J). Osteopontin (OPN), a myogenic inflammatory cytokine, was explored as a potential biomarker in dystrophic dogs over the disease course. The serum OPN levels of CXMD_J dystrophic dogs were elevated, even in the early disease phase, and this could be related to the presence of regenerating muscle fibers; as such, OPN would be a promising biomarker for muscle regeneration. Next, accelerometry, which is an efficient method to quantify performance in validated tasks, was used to evaluate motor function longitudinally in dystrophic dogs. We measured three-axis acceleration and angular velocity with wireless hybrid sensors during gait evaluations. Multiple parameters of acceleration and angular velocity showed notedly lower values in dystrophic dogs compared with wild-type dogs, even at the onset of muscle weakness. These parameters accordingly decreased with exacerbation of clinical manifestations along with the disease course. Multiple parameters also indicated gait abnormalities in dystrophic dogs, such as a waddling gait. These outcome measures could be applicable in clinical trials of patients with DMD or other muscle disorders.     

Knowledge and Perceptions about Clinical Trials and the Use of Biomedical Samples: Findings from a Qualitative Study in Rural Northern Ghana

IntroductionClinical trials conducted in sub-Saharan Africa have helped to address the prevalent health challenges. The knowledge about how communities perceive clinical trials is however only now evolving. This study was conducted among parents whose children participated in past clinical trials in northern Ghana to assess their knowledge and perceptions of clinical trials and the use of biomedical samples.MethodThis was a qualitative study based on eighty in-depth interviews with parents. The participants were randomly selected from among parents whose children were enrolled in a clinical trial conducted in the Kassena-Nankana districts between 2000 and 2003. The interviews were transcribed and coded into emergent themes using Nvivo 9 software. The thematic analysis framework was used to analyze the data.ResultsStudy participants reported that clinical trials were carried out to determine the efficacy of drugs and to make sure that these drugs were suitable for human beings to use. The conduct of clinical trials was perceived to have helped to reduce the occurrence of diseases such as malaria, cerebrospinal meningitis and diarrhea. Quality of care was reported to be better in clinical trials than in the routine care. Parents indicated that participation in clinical trials positively influenced their health-seeking behavior. Apprehensions about blood draw and the use to which samples were put were expressed, with suspicion by a few participants that researchers sold blood samples. The issue of blood draw was most contentious.ConclusionParents perception about the conduct of clinical trials in the study districts is generally positive. However, misconceptions made about the use of blood samples in this study must be taken seriously and strategies found to improve transparency and greater community acceptability.     

Clinical and biomarker endpoint analysis in neoadjuvant endocrine therapy trials

Neoadjuvant endocrine therapy trials for breast cancer are now a widely accepted investigational approach for oncology cooperative group and pharmaceutical company research programs. However, there remains considerable uncertainty regarding the most suitable endpoints for these studies, in part, because short-term clinical, radiological or biomarker responses have not been fully validated as surrogate endpoints that closely relate to long-term breast cancer outcome. This shortcoming must be addressed before neoadjuvant endocrine treatment can be used as a triage strategy designed to identify patients with endocrine therapy “curable” disease. In this summary, information from published studies is used as a basis to critique clinical trial designs and to suggest experimental endpoints for future validation studies. Three aspects of neoadjuvant endocrine therapy designs are considered: the determination of response; the assessment of surgical outcomes; and biomarker endpoint analysis. Data from the letrozole 024 (LET 024) trial that compared letrozole and tamoxifen is used to illustrate a combined endpoint analysis that integrates both clinical and biomarker information. In addition, the concept of a “cell cycle response” is explored as a simple post-treatment endpoint based on Ki67 analysis that might have properties similar to the pathological complete response endpoint used in neoadjuvant chemotherapy trials.