Treatment Response In Clinical Trials Research Articles

A framework for longitudinal latent factor modelling of treatment response in clinical trials with applications to Psoriatic Arthritis and Rheumatoid Arthritis

Objective:Clinical trials involve the collection of a wealth of data, comprising multiple diverse measurements performed at baseline and follow-up visits over the course of a trial. The most common primary analysis is restricted to a single, potentially composite endpoint at one time point. While such an analytical focus promotes simple and replicable conclusions, it does not necessarily fully capture the multi-faceted effects of a drug in a complex disease setting. Therefore, to complement existing approaches, we set out here to design a longitudinal multivariate analytical framework that accepts as input an entire clinical trial database, comprising all measurements, patients, and time points across multiple trials. Methods:Our framework composes probabilistic principal component analysis with a longitudinal linear mixed effects model, thereby enabling clinical interpretation of multivariate results, while handling data missing at random, and incorporating covariates and covariance structure in a computationally efficient and principled way. Results:We illustrate our approach by applying it to four phase III clinical trials of secukinumab in Psoriatic Arthritis (PsA) and Rheumatoid Arthritis (RA). We identify three clinically plausible latent factors that collectively explain 74.5% of empirical variation in the longitudinal patient database. We estimate longitudinal trajectories of these factors, thereby enabling joint characterisation of disease progression and drug effect. We perform benchmarking experiments demonstrating our method’s competitive performance at estimating average treatment effects compared to existing statistical and machine learning methods, and showing that our modular approach leads to relatively computationally efficient model fitting. Conclusion:Our multivariate longitudinal framework has the potential to illuminate the properties of existing composite endpoint methods, and to enable the development of novel clinical endpoints that provide enhanced and complementary perspectives on treatment response.

Comparison of response from RECIST1.1 and abstraction in real-world patients with lung cancer.

e21194 Background: Treatment response in clinical trials with solid tumors is measured by applying RECIST1.1 to radiographic images. However, response in real-world data (RWD) studies is based on information abstracted from clinician's notes. Differences in these two approaches can lead to bias when comparing response in trials to RWD. This study investigates the relationship between response from (1) certified radiologists applying RECIST1.1 to images from routine care and (2) electronic health records (EHR) notes-abstraction in the same patients. Methods: The nationwide Flatiron Health (FH) EHR-derived de-identified database was used to identify patients diagnosed with advanced non-small-cell lung cancer (aNSCLC) on/after Jan 1, 2011, with a visit in the FH network within 90 days of diagnosis, first line treatment (1L), and ≥1 radiographic image both at baseline (8 weeks before or at 1L start) and during 1L. RECIST1.1 and response abstraction were applied retrospectively to images and EHR notes obtained from routine care, respectively. For each patient, time-point responses were determined by RECIST1.1 (rwRECIST) and abstraction (rwR) and dichotomized as unconfirmed best overall response (BOR, complete+partial response = responder, all others = non-responder), and confirmed BOR if patients had an additional assessment. Results: We included 157 patients (59% on chemotherapy, 15%/12% on cancer immunotherapy combination/alone, 10% on targeted therapies). Patients had an image taken every 11 weeks (median). All images were readable and 75% were optimal quality. Response rate was lower by rwRECIST than rwR (unconfirmed: 48% vs 59%; confirmed: 34% vs 55%). Concordance in BOR between rwRECIST and rwR was 68%/60% for unconfirmed/confirmed response. Disagreement between rwRECIST and rwR was higher than inter-reader variability between radiologists and was mainly in one direction (rwR higher, Table). The disagreement was driven by patients deemed responders by abstraction who did not meet the -30% target lesion size cutoff specified by RECIST1.1 or presence of new lesions. Conclusions: RECIST1.1 can be applied to images from aNSCLC routine oncology care, although limited by image availability and less frequent assessment than trials. Differences were observed in response measured by rwRECIST and by abstraction. [Table: see text]

Revealing Individual Neuroanatomical Heterogeneity in Alzheimer Disease Using Neuroanatomical Normative Modeling.

Alzheimer disease (AD) is highly heterogeneous, with marked individual differences in clinical presentation and neurobiology. To explore this, we used neuroanatomical normative modeling to index regional patterns of variability in cortical thickness. We aimed to characterize individual differences and outliers in cortical thickness in patients with AD, people with mild cognitive impairment (MCI), and controls. Furthermore, we assessed the relationships between cortical thickness heterogeneity and cognitive function, β-amyloid, phosphorylated-tau, and ApoE genotype. Finally, we examined whether cortical thickness heterogeneity was predictive of conversion from MCI to AD. Cortical thickness measurements across 148 brain regions were obtained from T1-weighted MRI scans from 62 sites of the Alzheimer's Disease Neuroimaging Initiative. AD was determined by clinical and neuropsychological examination with no comorbidities present. Participants with MCI had reported memory complaints, and controls were cognitively normal. A neuroanatomical normative model indexed cortical thickness distributions using a separate healthy reference data set (n = 33,072), which used hierarchical Bayesian regression to predict cortical thickness per region using age and sex, while adjusting for site noise. Z-scores per region were calculated, resulting in a Z-score brain map per participant. Regions with Z-scores <-1.96 were classified as outliers. Patients with AD (n = 206) had a median of 12 outlier regions (out of a possible 148), with the highest proportion of outliers (47%) in the parahippocampal gyrus. For 62 regions, over 90% of these patients had cortical thicknesses within the normal range. Patients with AD had more outlier regions than people with MCI (n = 662) or controls (n = 159) (F(2, 1,022) = 95.39, p = 2.0 × 10-16). They were also more dissimilar to each other than people with MCI or controls (F(2, 1,024) = 209.42, p = 2.2 × 10-16). A greater number of outlier regions were associated with worse cognitive function, CSF protein concentrations, and an increased risk of converting from MCI to AD within 3 years (hazard ratio 1.028, 95% CI 1.016-1.039, p = 1.8 × 10-16). Individualized normative maps of cortical thickness highlight the heterogeneous effect of AD on the brain. Regional outlier estimates have the potential to be a marker of disease and could be used to track an individual's disease progression or treatment response in clinical trials.

MACHINE LEARNING-BASED PREDICTION OF GEBOES SCORE AND HISTOLOGIC IMPROVEMENT AND REMISSION THRESHOLDS IN ULCERATIVE COLITIS

Abstract BACKGROUND Histology is emerging as a key therapeutic endpoint for ulcerative colitis driven by associations between histologic response and long-term outcomes. However, existing scoring systems are subjective and consequently have variable inter- and intra-reader variability. Geboes scoring is a well-established system for ulcerative colitis histologic assessment that has previously been used to define thresholds for histo-endoscopic mucosal improvement (Geboes Score ≤3.1, together with Mayo score 0 or 1) and histologic remission (Geboes Score &amp;lt;2). Here we report the first machine learning (ML)-based prediction of the Geboes Score, and Geboes Score-derived thresholds of histologic improvement and remission, directly from whole slide images (WSI) of hematoxylin and eosin (H&amp;E)-stained mucosal biopsies. METHODS 3,148 WSI were scored by three expert gastrointestinal pathologists and the median consensus score was used to determine the Geboes score for each slide as ground truth. ML models were trained on median consensus scores to predict the Geboes score and subscores for each slide. Model performance vs. pathologist median consensus score was measured using accuracy and the F1 score, which accounts for both false positive and false negative errors. RESULTS The ML-based model performance, measured against median consensus scores of three pathologists, showed strong performance at predicting overall Geboes Score, with a quadratic kappa of 0.89. The model was also able to predict both histologic improvement and histologic remission with high accuracy. For predicting histological improvement as defined by a Geboes Score of ≤3.1, the model showed accuracy of 0.92 and F1 score of 0.92 (Figure 1). For predicting histological remission as defined by a Geboes Score of &amp;lt; 2, the model showed accuracy of 0.91 and F1 score of 0.89 (Figure 2). CONCLUSIONS We report a ML-based approach for predicting Geboes score and Geboes score-based key thresholds of histologic improvement and histologic remission. Model predictions show high accuracy compared to median consensus pathologist scores. This approach may enable standardized, reproducible and accurate prediction of these clinically relevant thresholds to better measure histologic disease activity and treatment response in clinical trials.

Ultrasonography in the assessment of disease activity in cranial and large-vessel giant cell arteritis: a prospective follow-up study.

We evaluated sensitivity to change and discriminative abilities of vascular US scores in disease monitoring in the follow-up of a prospective cohort of new-onset cranial and large-vessel (LV) GCA patients. Baseline and follow-up (8 weeks, 24 weeks and 15 months) US of temporal arteries (TA), carotid and axillary arteries (LV) included assessment of halo and measurement of the intima media complex (IMC). Max IMC, max halo IMC, sum IMC, sum halo IMC, mean IMC, halo count and the Southend halo score were calculated. The provisional OMERACT US score, OGUS, was obtained, taking the average of temporal arteries and axillary arteries IMCs divided by their normal cut-off values. Baseline US was positive in 44/47 patients (72% TA, 72% LV). Sensitivity to change of all composite US scores containing TAs was evident by week 8 onward. LVs responded poorly and new axillary US lesions emerged in six patients despite clinical remission. The OGUS showed a large magnitude of change and is considered the score least prone to potential bias. All TA-based US scores showed moderate-strong correlation with disease activity markers. OGUS, TA halo count, Southend TA halo score, TA sum IMC and TA mean IMC showed potential to discriminate remission and relapse with area under the curve ≥0.8. The OGUS is suggested as an outcome measurement for the assessment of treatment response in clinical trials. The abilities of US scores to discriminate remission and relapse are encouraging and should be further explored.

Comprehensive morphometric assessment of deltoid muscle development in children: A cross-sectional study.

Normative values for different morphometric parameters of muscle fibres during paediatric development, i.e. from 0 to 18 years, are currently unavailable. They would be of major importance to accurately evaluate pathological changes and could be used as reference biomarkers for evaluating treatment response in clinical trials, or physiological adjustments in sports or ageing. Data were derived from 482 images with a total of 33094 fibres from 10μm cross-sections of snap-frozen muscle from 83 deltoid muscle biopsies from patients, 0-18 years, without neuromuscular pathology stained with ATPase 9.4. Data was acquired and analysed with patented image analysis algorithms from "CARPACCIO.cloud". Several parameters were extracted or calculated, including cross-sectional area (CSA), fibre type, circularity, as well as the Minimum diameter of Feret (MinFeret). This study illustrates changes in quantitative parameters for muscle morphology over the course of paediatric development and the pivotal changes occurring around puberty. Only fibre size parameters (MinFeret, CSA) are dependent on gender, and only after puberty. All other parameters vary in a similar manner for females and males. The proportion of type 1 fibres is essentially constant from birth to age 10, decreasing to ≈40% by age 18. Circularity decreases with age, to plateau after age 10 for both fibre types. Normative values and reference charts for muscle fibre types in this age range have been generated to allow comparison of data from patients in pathology laboratories working on neuromuscular diseases. BPI FRANCE, PULSALYS, Association de l'Institut de Myologie, French National Research Agency (ANR), LABEX CORTEX of Université de Lyon.

Pain-autonomic measures reveal nociceptive sensitization in complex regional pain syndrome.

Allodynia and hyperalgesia are common signs in individuals with complex regional pain syndrome (CRPS), mainly attributed to sensitization of the nociceptive system. Appropriate diagnostic tools for the objective assessment of such hypersensitivities are still lacking, which are essential for the development of mechanism-based treatment strategies. This study investigated the use of pain-autonomic readouts to objectively detect sensitization processes in CRPS. Twenty individuals with chronic CRPS were recruited for the study alongside 16 age- and sex-matched healthy controls (HC). All individuals underwent quantitative sensory testing and neurophysiological assessments. Sympathetic skin responses (SSRs) were recorded in response to 15 pinprick and 15 noxious heat stimuli of the affected (CRPS hand/foot) and a control area (contralateral shoulder/hand). Individuals with CRPS showed increased mechanical pain sensitivity and increased SSR amplitudes compared with HC in response to pinprick and heat stimulation of the affected (p< 0.001), but not in the control area (p> 0.05). Habituation of pinprick-induced SSRs was reduced in CRPS compared to HC in both the affected (p= 0.018) and slightly in the control area (p= 0.048). Habituation of heat-induced SSR was reduced in CRPS in the affected (p= 0.008), but not the control area (p= 0.053). This is the first study demonstrating clinical evidence that pain-related autonomic responses may represent objective tools to quantify sensitization processes along the nociceptive neuraxis in CRPS (e.g. widespread hyperexcitability). Pain-autonomic readouts could help scrutinize mechanisms underlying the development and maintenance of chronic pain in CRPS and provide valuable metrics to detect mechanism-based treatment responses in clinical trials. This study provides clinical evidence that autonomic measures to noxious stimuli can objectively detect sensitization processes along the nociceptive neuraxis in complex regional pain syndrome (CRPS) (e.g. widespread hyperexcitability). Pain-autonomic readouts may represent valuable tools to explore pathophysiological mechanisms in a variety of pain patients and offer novel avenues to help guide mechanism-based therapeutic strategies.

Diffusion Tensor Imaging Reveals Elevated Diffusivity of White Matter Microstructure that Is Independently Associated with Long-Term Outcome after Mild Traumatic Brain Injury: A TRACK-TBI Study.

Diffusion tensor imaging (DTI) literature on single-center studies contains conflicting results regarding acute effects of mild traumatic brain injury (mTBI) on white matter (WM) microstructure and the prognostic significance. This larger-scale multi-center DTI study aimed to determine how acute mTBI affects WM microstructure over time and how early WM changes affect long-term outcome. From Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI), a cohort study at 11 United States level 1 trauma centers, a total of 391 patients with acute mTBI ages 17 to 60 years were included and studied at two weeks and six months post-injury. Demographically matched friends or family of the participants were the control group (n = 148). Axial diffusivity (AD), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) were the measures of WM microstructure. The primary outcome was the Glasgow Outcome Scale Extended (GOSE) score of injury-related functional limitations across broad life domains at six months post-injury. The AD, MD, and RD were higher and FA was lower in mTBI versus friend control (FC) at both two weeks and six months post-injury throughout most major WM tracts of the cerebral hemispheres. In the mTBI group, AD and, to a lesser extent, MD decreased in WM from two weeks to six months post-injury. At two weeks post-injury, global WM AD and MD were both independently associated with six-month incomplete recovery (GOSE <8 vs = 8) even after accounting for demographic, clinical, and other imaging factors. DTI provides reliable imaging biomarkers of dynamic WM microstructural changes after mTBI that have utility for patient selection and treatment response in clinical trials. Continued technological advances in the sensitivity, specificity, and precision of diffusion magnetic resonance imaging hold promise for routine clinical application in mTBI.

Levels of Neurofilament Light at the Preataxic and Ataxic Stages of Spinocerebellar Ataxia Type 1.

Neurofilament light (NfL) appears to be a promising fluid biomarker in repeat-expansion spinocerebellar ataxias (SCAs), with piloting studies in mixed SCA cohorts suggesting that NfL might be increased at the ataxic stage of SCA type 1 (SCA1). We here hypothesized that NfL is increased not only at the ataxic stage of SCA1, but also at its (likely most treatment-relevant) preataxic stage. We assessed serum NfL (sNfL) and CSF NfL (cNfL) levels in both preataxic and ataxic SCA1, leveraging a multicentric cohort recruited at 6 European university centers, and clinical follow-up data, including actually observed (rather than only predicted) conversion to the ataxic stage. Levels of sNfL and cNfL were assessed by single-molecule array and ELISA technique, respectively. Forty individuals with SCA1 (23 preataxic, 17 ataxic) and 89 controls were enrolled, including 11 preataxic individuals converting to the ataxic stage. sNfL levels were increased at the preataxic (median 15.5 pg/mL [interquartile range 10.5-21.1 pg/mL]) and ataxic stage (31.6 pg/mL [26.2-37.7 pg/mL]) compared to controls (6.0 pg/mL [4.7-8.6 pg/mL]), yielding high age-corrected effect sizes (preataxic: r = 0.62, ataxic: r = 0.63). sNfL increases were paralleled by increases of cNfL at both the preataxic and ataxic stage. In preataxic individuals, sNfL levels increased with proximity to predicted ataxia onset, with significant sNfL elevations already 5 years before onset, and confirmed in preataxic individuals with actually observed ataxia onset. sNfL increases were detected already in preataxic individuals with SCA1 without volumetric atrophy of cerebellum or pons, suggesting that sNfL might be more sensitive to early preataxic neurodegeneration than the currently known most change-sensitive regions in volumetric MRI. Using longitudinal sNfL measurements, we estimated sample sizes for clinical trials with the reduction of sNfL as the endpoint. sNfL levels might provide easily accessible peripheral biomarkers in both preataxic and ataxic SCA1, allowing stratification of preataxic individuals regarding proximity to onset, early detection of neurodegeneration even before volumetric MRI alterations, and potentially capture of treatment response in clinical trials. ClinicalTrials.gov Identifier: NCT01037777. This study provides Class III evidence that NfL levels are increased in both ataxic and preataxic SCA1 and are associated with ataxia onset.

New developments of biofluid-based biomarkers for routine diagnosis and disease trajectories in frontotemporal dementia.

Frontotemporal dementia (FTD) covers a spectrum of neurodegenerative disorders with different phenotypes, genetic backgrounds, and pathological states. Its clinicopathological diversity challenges the diagnostic process and the execution of clinical trials, calling for specific diagnostic biomarkers of pathologic FTD types. There is also a need for biomarkers that facilitate disease staging, quantification of severity, monitoring in clinics and observational studies, and for evaluation of target engagement and treatment response in clinical trials. This review discusses current FTD biofluid-based biomarker knowledge taking into account the differing applications. The limitations, knowledge gaps, and challenges for the development and implementation of such markers are also examined. Strategies to overcome these hurdles are proposed, including the technologies available, patient cohorts, and collaborative research initiatives. Access to robust and reliable biomarkers that define the exact underlying pathophysiological FTD process will meet the needs for specific diagnosis, disease quantitation, clinical monitoring, and treatment development.

Abstract 9: Pervasive White Matter Microstructure Dysintegrity Related To High Blood Pressure Among Asymptomatic Population

Background: Blood pressure is the strongest contributor to clinically evident cerebrovascular disease. We investigated the role of blood pressure on white matter (WM) microstructure among asymptomatic individuals without clinically evident cerebrovascular disease. Methods: We conducted a nested study within the UK Biobank, restricting our analysis to participants without cerebrovascular disease or dementia and with available brain diffusion tensor imaging (DTI). We tested for association between systolic blood pressure (SBP) and six different DTI metrics: fractional anisotropy (FA), mean diffusivity (MD), tensor mode (MO), intra-cellular volume fraction (ICVF), isotropic or free water volume fraction (ISOVF), and orientation dispersion index (OD) across 48 WM tracts using multivariable linear regression adjusted for potential confounders. We used Bonferroni-corrected p-values (0.05/48) for statistical significance. Results: We analyzed 33,440 participants. Mean age was 63.0 (SD 7.7), and 17,688 (53%) were female. Higher SBP is independently associated with pervasive decrease in FA and ICVF and increase in MD (Figure), after adjustment for vascular risk-factors. SBP was also associated with lower neurite OD (a more specific metric of axonal damage) in bilateral posterior corona radiata, external capsule, medial lemniscus, and corticospinal tracs. FA and OD of external capsule and posterior corona radiata had the largest drop per 10 mmHg increase of SBP (steepest slope). Conclusions: Higher SBP is associated with pervasive WM microstructure dysintegrity in asymptomatic individuals without evident cerebrovascular disease. DTI metrics of the posterior corona radiata and external capsule are most reflective of variations in SBP and may provide a potential biomarker to assess subtle WM microstructural damage in hypertensive patients or monitor treatment response in clinical trials.

Parsing heterogeneity within dementia with Lewy bodies using clustering of biological, clinical, and demographic data

BackgroundDementia with Lewy bodies (DLB) includes various core clinical features that result in different phenotypes. In addition, Alzheimer’s disease (AD) and cerebrovascular pathologies are common in DLB. All this increases the heterogeneity within DLB and hampers clinical diagnosis. We addressed this heterogeneity by investigating subgroups of patients with similar biological, clinical, and demographic features.MethodsWe studied 107 extensively phenotyped DLB patients from the European DLB consortium. Factorial analysis of mixed data (FAMD) was used to identify dimensions in the data, based on sex, age, years of education, disease duration, Mini-Mental State Examination (MMSE), cerebrospinal fluid (CSF) levels of AD biomarkers, core features of DLB, and regional brain atrophy. Subsequently, hierarchical clustering analysis was used to subgroup individuals based on the FAMD dimensions.ResultsWe identified 3 dimensions using FAMD that explained 38% of the variance. Subsequent hierarchical clustering identified 4 clusters. Cluster 1 was characterized by amyloid-β and cerebrovascular pathologies, medial temporal atrophy, and cognitive fluctuations. Cluster 2 had posterior atrophy and showed the lowest frequency of visual hallucinations and cognitive fluctuations and the worst cognitive performance. Cluster 3 had the highest frequency of tau pathology, showed posterior atrophy, and had a low frequency of parkinsonism. Cluster 4 had virtually normal AD biomarkers, the least regional brain atrophy and cerebrovascular pathology, and the highest MMSE scores.ConclusionsThis study demonstrates that there are subgroups of DLB patients with different biological, clinical, and demographic characteristics. These findings may have implications in the diagnosis and prognosis of DLB, as well as in the treatment response in clinical trials.

Neuroanatomical correlates of speech and singing production in chronic post-stroke aphasia.

A classical observation in neurology is that aphasic stroke patients with impairments in speech production can nonetheless sing the same utterances. This preserved ability suggests a distinctive neural architecture for singing that could contribute to speech recovery. However, to date, these structural correlates remain unknown. Here, we combined a multivariate lesion–symptom mapping and voxel-based morphometry approach to analyse the relationship between lesion patterns and grey matter volume and production rate in speech and singing tasks. Lesion patterns for spontaneous speech and cued repetition extended into frontal, temporal and parietal areas typically reported within the speech production network. Impairment in spontaneous singing was associated with damage to the left anterior–posterior superior and middle temporal gyri. Preservation of grey matter volume in the same regions where damage led to poor speech and singing production supported better performance in these tasks. When dividing the patients into fluent and dysfluent singers based on the singing performance from demographically matched controls, we found that the preservation of the left middle temporal gyrus was related to better spontaneous singing. These findings provide insights into the structural correlates of singing in chronic aphasia and may serve as biomarkers to predict treatment response in clinical trials using singing-based interventions for speech rehabilitation.

The Value of Liver and Spleen Stiffness for Evaluation of Portal Hypertension in Compensated Cirrhosis.

Patients with compensated advanced chronic liver disease who develop clinically significant portal hypertension (CSPH) are at high risk for hepatic decompensation and mortality if left untreated. Liver biopsy and hepatic venous pressure gradient (HVPG) measurements are the current gold standard procedures for determining fibrosis severity and diagnosing CSPH, respectively; however, both are invasive, limiting their use in clinical practice and larger trials of novel agents. As such, there is an unmet clinical need for reliable, validated, noninvasive measures to detect CSPH and to further assess portal hypertension (PH) severity. Alterations in the biomechanical properties of the liver or spleen in patients with cirrhosis can be quantified by tissue elastography, which examines the elastic behavior of tissue after a force has been applied. A variety of methods are available, including magnetic resonance elastography, shear‐wave elastography, and the most thoroughly investigated measure, vibration‐controlled transient elastography. Liver stiffness (LS) and spleen stiffness (SS) measurements offer valuable alternatives to detect and monitor CSPH. Both LS and SS correlate well with HVPG, with thresholds of LS >20‐25 kPa and SS >40‐45 kPa indicating a high likelihood of CSPH. Because SS is a direct and dynamic surrogate of portal pressure, it has the potential to monitor PH severity and assess PH improvement as a surrogate marker for clinical outcomes. Importantly, SS seems to be superior to LS for monitoring treatment response in clinical trials focusing on reducing PH.

Prognostic Factors for Dry Eye Disease Treatment Response in Clinical Trials

Prognostic Factors for Dry Eye Disease Treatment Response in Clinical Trials

Circulating microRNAs from the mouse tibia fracture model reflect the signature from patients with complex regional pain syndrome.

Complex regional pain syndrome (CRPS) often results from an initial trauma that later produces a disproportionate amount of pain. The mechanisms underlying CRPS have been studied using a tibia fracture model (TFM) in rodents because this model closely mimics symptoms and has several molecular correlates observed in patients with CRPS. Here, we determined whether the TFM has alterations in circulating microRNAs (miRNAs) and cytokines transported by small extracellular vesicles (sEVs) that faithfully model previously reported miRNA alterations from patients with CRPS. We isolated and characterized serum-derived sEVs from mice 3 weeks after fracture when symptoms such as pain hypersensitivity develop. Whole-transcriptome profiling was used to determine sEV miRNAs, and Bio-Plex Pro Mouse Cytokine 23-plex assay was used to measure cytokines. Differentially expressed miRNAs from TFM were compared with previously reported circulating miRNA alterations from patients with CRPS. Although sEV cytokine levels were unchanged, there were significant changes in sEV miRNA profiles. Differentially expressed miRNAs from TFM sEVs significantly overlapped with those previously reported in patients with CRPS. Of the 57 sEV miRNAs dysregulated in the TFM, 30 were previously reported in patients with CRPS compared with healthy control donors both in sEVs and 23 in whole blood. These findings enhance the validity of TFM as a model for CRPS and suggest that specific miRNA dysregulation may be a shared feature of CRPS and the TFM. These dysregulated miRNAs could help identify mechanistic targets or serve as biomarker candidates for both diagnosis and treatment responses in clinical trials.

Reporting standards for primary sclerosing cholangitis using MRI and MR cholangiopancreatography: guidelines from MR Working Group of the International Primary Sclerosing Cholangitis Study Group.

Primary sclerosing cholangitis (PSC) is a chronic inflammatory disorder affecting the bile ducts and is characterized by biliary strictures, progressive liver parenchymal fibrosis, and an increased risk of hepatobiliary malignancies primarily cholangiocarcinoma (CCA). PSC may lead to portal hypertension, liver decompensation, and liver failure with the need for liver transplantation. Magnetic resonance imaging (MRI)/magnetic resonance cholangiopancreatography (MRCP) are considered the imaging standard for diagnosis and follow-up in patients with PSC. Currently, there are no universally accepted reporting standards and definitions for MRI/MRCP features. Controversies exist about the definition of a high-grade stricture and there is no widely agreed approach to their management. The members of the MRI working group of the International Primary Sclerosing Cholangitis Study Group (IPSCSG) sought to define terminologies and reporting standards for describing MRI/MRCP features that would be applied to diagnosis and surveillance of disease progression, and potentially for evaluating treatment response in clinical trials. In this extensive review, the technique of MRI/MRCP and assessment of image quality for the evaluation of PSC is briefly described. The definitions and terminologies for severity and length of strictures, duct wall thickening and hyperenhancement, and liver parenchyma signal intensity changes are outlined. As CCA is an important complication of PSC, standardized reporting criteria for CCA developing in PSC are summarized. Finally, the guidelines for reporting important changes in follow-up MRI/MRCP studies are provided. KEY POINTS: • Primary sclerosing cholangitis is a chronic inflammatory disorder affecting the bile ducts, causing biliary strictures and liver fibrosis and an increased risk of cholangiocarcinoma. • This consensus document provides definitions and suggested reporting standards for MRI and MRCP features of primary sclerosing cholangitis, which will allow for a standardized approach to diagnosis, assessment of disease severity, follow-up, and detection of complications. • Standardized definitions and reporting of MRI/MRCP features of PSC will facilitate comparison between studies, promote longitudinal assessment during management, reduce inter-reader variability, and enhance the quality of care and communication between health care providers.

Connectivity Correlates of Anxiety Symptoms in Drug-Naive Parkinson's Disease Patients.

Anxiety symptoms are common in Parkinson's disease (PD). A link between anxiety and cognitive impairment in PD has been demonstrated. Using resting-state functional magnetic resonance imaging, we investigated intrinsic brain network connectivity correlates of anxiety symptoms in a cohort of drug-naive, cognitively unimpaired patients with PD. The intrinsic functional brain connectivity of 25 drug-naive, cognitively unimpaired PD patients with anxiety, 25 without anxiety, and 20 matched healthy controls was compared. All patients underwent a detailed behavioral and neuropsychological evaluation. Anxiety presence and severity were assessed using the Parkinson's Disease Anxiety Scale. Single-subject and group-level independent component analyses were used to investigate functional connectivity differences within and between the major resting-state networks. Decreased connectivity within the default-mode and sensorimotor networks (SMN), increased connectivity within the executive-control network (ECN), and divergent connectivity measures within salience and frontoparietal networks (SN and FPN) were detected in PD patients with anxiety compared with those without anxiety. Moreover, patients with anxiety showed a disrupted inter-network connectivity between SN and SMN, ECN, and FPN. Anxiety severity was correlated with functional abnormalities within these networks. Our findings demonstrated that an abnormal intrinsic connectivity within and between the most reported large-scale networks may represent a potential neural correlate of anxiety symptoms in drug-naive PD patients even in the absence of clinically relevant cognitive impairment. We hypothesize that these specific cognitive and limbic network architecture changes may represent a potential biomarker of treatment response in clinical trials. © 2020 International Parkinson and Movement Disorder Society.

Evaluation of blood gene expression levels in facioscapulohumeral muscular dystrophy patients

Facioscapulohumeral muscular dystrophy (FSHD) is caused by the expression of DUX4 in skeletal muscles. A number of therapeutic approaches are being developed to antagonize the events preceding and following DUX4 expression that leads to muscular dystrophy. Currently, the possibility to evaluate treatment response in clinical trials is hampered by the lack of objective molecular biomarkers connecting the disease cause to clinical performance. In this study we employed RNA-seq to examine gene expression in PAXgene tubes obtained from two independent cohorts of FSHD patients. Analysis of gene expression profiles did not lead to the identification of genes or pathways differentially expressed in FSHD patients, or associated with disease severity. In particular, we did not find evidence that the DUX4 and PAX7 signatures were differentially expressed. On the other hand, we were able to improve patient classification by including single genes or groups of genes in classification models. The best classifier was ROPN1L, a gene known to be expressed in testis, coincidentally the typical location of DUX4 expression. These improvements in patient classification hold the potential to enrich the FSHD clinical trial toolbox.

Abstract 1406: Are circulating microRNAs (miRNAs) ready for inclusion as biomarkers in breast cancer clinical trials

Abstract Background: Circulating miRNAs have potential as surrogate measures of tumor burden to monitor treatment response in clinical trials due to their association with cancer and high stability in blood. Greystoke et al (PMID: 26654130) showed that 10 miRNAs (miRs-200a, 200b, 200c, 141, 429, 95, 195, 210, 335, 375) were elevated in plasma of patients with a range of solid tumors compared to in plasma of healthy volunteers (HVs). The miRNA levels decreased after treatment, especially in patients with larger clinical responses. In the present study, the same 10 miRNAs, and 3 breast cancer (BC) related miRNAs identified in a literature search (miRs-18b, 21, 148b), were analysed to determine if their measurement i) is more sensitive in plasma or serum, ii) distinguishes BC patients from HVs, and iii) changes after surgery or systemic therapy. Methods: The 13-miRNA panel (13-plex) was analysed by qPCR in plasma and serum from 12 BC patients and 8 HVs, and in plasma from 19 BC patients pre- and 4 hours post-surgery with a multiplex of TaqManTM MiRNA Assays. Expression of the 13-plex was measured with custom TaqManTM Low Density Array (TLDA) cards after pre-amplification, in serum collected at cycle 1, day 1 (C1D1) and day 8 (C1D8) from 44 BC patients starting adjuvant chemotherapy on the B-AHEAD 2 study (ISRCTN04156504). Endogenous miR-16 and exogenous ath-miR-159a provided standards to assess miRNA extraction efficiency. Results are reported as the geometric means of the 40-Ct values for the 13 miRNAs (geomean13). Results: Expression of the 13-plex was significantly higher in plasma compared to in matched serum. TLDA analysis of 381 miRNAs confirmed that the plasma to serum superiority was a general effect not restricted to the 13-plex. The superiority of plasma was reduced however by pre-amplification; in the 381-miRNA TLDA analysis, detection in serum improved compared to in the multiplex qPCR assay. The 13-plex was elevated in plasma of BC patients compared to HVs (p = 0.015). There was a trend towards a reduction after surgery, but the difference did not reach statistical significance. However, miR-195, a BC specific marker, was significantly lower after surgery (p = 0.0001). In the B-AHEAD 2 study cohort, the 13-plex was decreased at C1D8 compared to C1D1 (p = 0.0002). The three patients who relapsed within 5 years of diagnosis had geomean13 values at C1D1 of 10.3, 10.6 and 11.8 compared to the median of 10.3 for all patients. Given the low event rate, either a larger patient cohort or a cohort with a higher event rate is required to assess association with clinical outcome. Conclusions: This study shows that plasma is better than serum for miRNA evaluation but that measures in serum are useful if cDNA is pre-amplified after reverse transcription. The 13-plex is elevated in BC, has a trend towards a fall after surgery and is reduced after chemotherapy. The 13-plex has potential as a biomarker of tumor burden in BC trials. Citation Format: Edward B. Amankwatia, Alexandra Bennett, David Ou, David Jamieson, Nicola Cresti, Henry Cain, Rosie McNeillis, Jonathan Womack, Sacha Howell, Michelle Harvie, Felicity May, Alastair Greystoke. Are circulating microRNAs (miRNAs) ready for inclusion as biomarkers in breast cancer clinical trials [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1406.