BACKGROUND:Causality assessment of suspected drug-induced liver injury (DILI) during metabolic dysfunction-associated steatohepatitis (MASH) clinical trials can be challenging, and liver biopsies are not routinely performed as part of this evaluation. While the field is moving away from liver biopsy as a diagnostic and prognostic tool, information not identified by non-invasive testing may be provided on histology. AIM:To address the appropriate utilisation of liver biopsy as part of DILI causality assessment in this setting. METHODS:From 2020 to 2022, the Liver Forum convened a series of webinars on issues pertaining to liver biopsy during MASH trials. The Histology Working Group was formed to generate a series of consensus documents addressing these challenges. This manuscript focuses on liver biopsy as part of DILI causality assessment. RESULTS:Expert opinion, guidance and recommendations on the role of liver biopsy as part of causality assessment of suspected DILI occurring during clinical trials for a drug(s) being developed for MASH are provided. Lessons learned from prior MASH programs are reviewed and gaps identified. CONCLUSIONS:Although there are no pathognomonic features, histologic evaluation of suspected DILI during MASH clinical trials may alter patient management, define the pattern and severity of injury, detect findings that favour a diagnosis of DILI versus MASH progression, identify prognostic features, characterise the clinicopathological phenotype of DILI, and/or define lesions that influence decisions about trial discontinuation and further development of the drug.

HepatologyVolume 73, Issue 5 p. 2023-2027 Special Article Nonalcoholic Steatohepatitis: Current Thinking From the Division of Hepatology and Nutrition at the Food and Drug Administration Frank A. Anania, Corresponding Author Frank.Anania@fda.hhs.gov Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MD ADDRESS CORRESPONDENCE AND REPRINT REQUESTS TO: Frank A. Anania, M.D. Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 E-mail: Frank.Anania@fda.hhs.gov Tel.: +1-240-402-4975Search for more papers by this authorLara Dimick-Santos, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorRuby Mehta, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorJoseph Toerner, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorJulie Beitz, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this author Frank A. Anania, Corresponding Author Frank.Anania@fda.hhs.gov Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MD ADDRESS CORRESPONDENCE AND REPRINT REQUESTS TO: Frank A. Anania, M.D. Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 E-mail: Frank.Anania@fda.hhs.gov Tel.: +1-240-402-4975Search for more papers by this authorLara Dimick-Santos, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorRuby Mehta, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorJoseph Toerner, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this authorJulie Beitz, Center for Drug Evaluation and Research Office of New Drugs, Office of Inflammation and Immunity, Division of Hepatology and Nutrition, US Food and Drug Administration, Silver Spring, MDSearch for more papers by this author First published: 19 December 2020 https://doi.org/10.1002/hep.31687 The views expressed in this report are those of the authors and do not necessarily represent the opinions of the FDA, the US Department of Health and Human Services, or the US government. Potential conflict of interest: Nothing to report. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Volume73, Issue5May 2021Pages 2023-2027 RelatedInformation

Nonalcoholic fatty liver disease (NAFLD) has emerged as a major public health threat and it is dynamic in its natural history of disease progression. The burden of end-stage liver disease due to this condition is projected to increase by 200% to 300% over the next 2 decades.1 This has led to intense drug development efforts to establish effective therapy for this condition.2 Two major approaches are being taken to treat nonalcoholic steatohepatitis (NASH): (1) targeting the metabolic underpinning of the disease and other upstream drivers of disease activity,2 and (2) targeting downstream elements of disease course, such as fibrosis, to reduce disease progression.

Nonalcoholic fatty liver disease (NAFLD) has quickly become the most common chronic liver disease in children in many countries around the world.1–5 Estimates in Europe range from 1.3% to 22.5% of children being affected.2,6–9 In the United States, 9.6% of all children and 38.0% of obese adolescents are estimated to have NAFLD.10,11 In China, 45% of obese adolescents are estimated to have NAFLD.12 Certain populations have notable predisposition; for example, in the United States, the highest prevalence is found in Mexican Americans.

BACKGROUND:Bile acids play important roles in cholesterol metabolism and signal through farnesoid X receptor and G protein-coupled receptors. Given their importance in liver biology, bile acid therapy enables therapeutic applications beyond the treatment of cholestatic liver disease. However, predicting hepatotoxicity of bile acids in humans is obscured due to inconsistent extrapolations of animal data to humans.AIM:To review the evidence that could explain discordant bile acids hepatotoxicity observed in humans and animals.METHOD:Literature search was conducted in PubMed using keywords "bile acid," "transporter," "hepatotoxicity," "clinical study," "animal study," "species difference," "mechanism," "genetic disorder." Relevant articles were selected for review.RESULTS:Clinically significant hepatotoxicity was reported in response to certain bile acids, namely chenodeoxycholic acid, which was given a boxed warning for potential hepatotoxicity. The chemical structure, specifically the number and orientation of hydroxyl groups, significantly affects their hydrophobicity, an important factor in bile acid toxicity. Experimental studies show that hydrophobic bile acids can lead to liver injury through various mechanisms, such as death receptor signalling, mitochondrial dysfunction and inflammation. Although animal studies play a central role in investigating bile acid safety, there are considerable differences in bile acid composition, metabolism and hepatobiliary disposition across species. This does not allow appropriate safety inference, especially for predicting hepatotoxicity in humans. Exploring evidences stemming from inborn errors, genetic models of disease and toxicology studies further improves an understanding of bile acid hepatotoxicity.CONCLUSION:Species differences should be considered in the development of bile acid related therapeutics. Although the mechanism of bile acid hepatotoxicity is still not fully understood, continued mechanistic studies will deepen our understanding.

Primary sclerosing cholangitis is an enigmatic disease affecting the bile ducts, eventually leading to liver failure necessitating liver transplantation in many cases. There is currently no therapy that has proven to halt disease progression. One of the reasons for this is the lack of proper endpoints to measure the effect of medical intervention on the course of the disease. Relevant clinical endpoints such as death or liver transplantation occur too infrequently in this orphan disease to be used as endpoints in phase 2 or 3 trials. It is therefore of utmost importance to identify appropriate surrogate endpoints that are reasonably likely to measure true clinical benefit. This article will discuss a number of surrogate endpoints that are likely candidates to serve this role. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease in the world, affecting an estimated 25% of the global adult population.1Younossi Z.M. Koenig A.B. Abdelatif D. et al.Global epidemiology of non-alcoholic fatty liver disease-meta-analytic assessment of prevalence, incidence and outcomes.Hepatology. 2016; 64: 73-84Crossref PubMed Scopus (6792) Google Scholar Liver-related morbidity and mortality attributed to NAFLD are substantial, and fibrosis seems to be the strongest independent predictor of outcome.2Angulo P. Kleiner D.E. Dam-Larsen S. et al.Liver fibrosis, but no other histologic features, is associated with long-term outcomes of patients with nonalcoholic fatty liver disease.Gastroenterology. 2015; 149: 389-397.e10Abstract Full Text Full Text PDF PubMed Scopus (2015) Google Scholar Fibrosis develops among patients with the nonalcoholic steatohepatitis (NASH) phenotype, making it the biologically relevant focus of drug development.3McPherson S. Hardy T. Henderson E. et al.Evidence of NAFLD progression from steatosis to fibrosing-steatohepatitis using paired biopsies: implications for prognosis and clinical management.J Hepatol. 2015; 62: 1148-1155Abstract Full Text Full Text PDF PubMed Scopus (758) Google Scholar Currently, there are no approved therapies to treat NASH, although many drugs are in development. Multiple challenges exist in drug development for NASH, including the inconsistent measurement of baseline parameters, which makes interpretation and comparison of trial data difficult. As drug development proceeds, there is a need to standardize data collected as well as aspects of study design (eg, stratification factors) to make datasets comparable and assist the regulatory agencies' efforts to determine efficacy and safety. To support efforts in NASH drug development, the Liver Forum first convened after the 2013 American Association for the Study of Liver Diseases and US Food and Drug Administration co-sponsored conference on clinical trial designs and endpoints in NASH.4Sanyal A.J. Friedman S.L. McCullough A.J. et al.Challenges and opportunities in drug and biomarker development for nonalcoholic steatohepatitis: findings and recommendations from an American Association for the Study of Liver Diseases-U.S. Food and Drug Administration Joint Workshop.Hepatology. 2015; 61: 1392-1405Crossref PubMed Scopus (277) Google Scholar The Liver Forum is an independent collaborative drug development and regulatory science project focused on diagnostics and treatments for NASH based on the established model of the Forum for Collaborative HIV Research.5Miller V. The forum for collaborative HIV research: a model for an integrated and inclusive approach to clinical research and drug development.Clin Pharmacol Ther. 2009; 86: 332-335Crossref PubMed Scopus (12) Google Scholar For this particular effort, the Liver Forum invited experts from stakeholder groups in academic medicine, regulatory agencies, the pharmaceutical and medical diagnostics industries, and patient advocacy organizations to develop consensus recommendations for standardized baseline parameters for NASH-related clinical trials. A working group of the Liver Forum assessed the state of the science in clinical trials for NASH and made specific recommendations for the categories of data to include in eligibility determinations and baseline assessments. As a first step, we reviewed recent and current placebo-controlled randomized clinical studies registered at clinicaltrials.gov for general patterns of study entry criteria and baseline data collection. For the purposes of this report, we defined broad categories of parameters to recommend for baseline data collection, including demographics and genetics; diet and activity including alcohol, tobacco, and substance use; concomitant medications; laboratory tests; and histology. Further recommendations regarding comorbidities and surgical history, anthropometrics, specialized biomarkers, imaging and other noninvasive diagnostics, and quality of life are available in the Supplementary Materials. For each category, specific variables were assessed for their relevancy with regard to therapeutic goal (ie, whether the drug target is liver fibrosis versus steatohepatitis), phase of trial, and whether the measure is essential, ideal, or should be considered. We further developed consensus strategy for stratified randomization for use in NASH-related trials (Supplementary Materials). Age, sex, and ethnicity are known risk modifiers for NAFLD and NASH (Supplementary Table 1). These factors are essential to capture as baseline parameters regardless of trial phase or mechanism of action. Epidemiologic studies suggest that NAFLD is more prevalent in males compared with females, which may be owing to different factors including insulin resistance, visceral adiposity, lifestyle, and sex hormones.6Lazo M. Hernaez R. Eberhardt M.S. et al.Prevalence of nonalcoholic fatty liver disease in the United States: the Third National Health and Nutrition Examination Survey, 1988-1994.Am J Epidemiol. 2013; 178: 38-45Crossref PubMed Scopus (634) Google Scholar Age is a risk factor for NAFLD fibrosis progression and of comorbid conditions such as cardiovascular disease.7Frith J. Day C.P. Henderson E. et al.Non-alcoholic fatty liver disease in older people.Gerontology. 2009; 55: 607-613Crossref PubMed Scopus (174) Google Scholar Aging effects on the liver include decreased volume, blood flow, and mitochondrial dysfunction. Race and ethnicity, often surrogates for unknown genetic polymorphisms, are considered important parameters to capture for proof-of-concept (POC) and phase II trials, and are recommended as essential components for phase III trials. These are typically self-reported given the current lack of better tools to characterize the underlying genetic factors that might contribute to NASH pathogenesis. The prevalence of NAFLD has been shown to vary by race and ethnicity, which is not fully explained by lifestyle or metabolic risk factors.8Schneider A.L. Lazo M. Selvin E. et al.Racial differences in nonalcoholic fatty liver disease in the U.S. population.Obesity (Silver Spring). 2014; 22: 292-299Crossref PubMed Scopus (93) Google Scholar Genetic polymorphisms in genes including PNPLA3, TM6SF2, and GCKR have been robustly associated with liver disease severity and/or cardiovascular risk in NAFLD.9Anstee Q.M. Seth D. Day C.P. Genetic factors that affect risk of alcoholic and nonalcoholic fatty liver disease.Gastroenterology. 2016; 150: 1728-1744.e7Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar These variants have specific ethnic distributions, with PNPLA3 accounting for ≤72% of interethnic variation in hepatic triglyceride content in the Dallas Heart Study.10Romeo S. Kozlitina J. Xing C. et al.Genetic variation in PNPLA3 confers susceptibility to nonalcoholic fatty liver disease.Nat Genet. 2008; 40: 1461-1465Crossref PubMed Scopus (2475) Google Scholar DNA (venous blood or extracted from tissue) should be collected and the informed consent process should include the ability to genotype these candidate genes as well as "genome-wide" analyses for future analysis. This is particularly important for phase III trials given their larger size. Genetic testing would also be useful for identifying genes that may predict risk of drug-induced liver injury for study drugs. Furthermore, determining the presence of genetic polymorphisms associated with NASH in trial patients will be essential for evaluating the impact of these polymorphisms on treatment response. Current candidates include PNPLA3 I148M and TM6SF2 E167K.11Brunt E.M. Wong V.W. Nobili V. et al.Nonalcoholic fatty liver disease.Nat Rev Dis Primers. 2015; 1: 15080Crossref PubMed Scopus (566) Google Scholar The appropriate standard of care for dietary and activity counseling should be provided to NAFLD patients before enrollment in clinical trials, not only because research ethics require that all patients receive standard-of-care treatment, but also to normalize the potential impact of lower caloric intake and increased activity on weight and NAFLD histologic severity (Supplementary Table 2). We recommend counseling regarding diet and activity take place 4 to 6 weeks before the baseline visit before initiation of the treatment phase. For practical purposes, the time period between the screening visit and baseline visit would be suitable as a "run-in period" to provide healthy lifestyle recommendations and minimize the possible confounding influence of dietary and activity changes. Standardization will be of particular importance in POC trials with changes in liver fat and eventually changes in alanine aminotransferase levels as primary or key secondary endpoints. Specific dietary recommendations exist; for example, the NASH Clinical Research Network (CRN) has recommended the National Cholesterol Education Program Step-1 diet for nondiabetics and the American Diabetes Association diet for diabetics for standard of care in NASH subjects. Similar healthy diet and increased exercise counseling are available in different countries and should be provided to participants in trials outside of the United States. Reinforcement of diet and healthy lifestyle habits should occur at visits throughout studies. Attempts should also be made to capture changes in diet and physical activity habits. The Alcohol Use Disorders Identification Test (AUDIT-C) is a screening tool developed by the World Health Organization and validated in 6 countries that can be used to exclude potential participants with heavy alcohol consumption and monitor the effect of modest alcohol intake on NAFLD during the course of a trial, as done previously by the NASH CRN.12Dunn W. Sanyal A.J. Brunt E.M. et al.Modest alcohol consumption is associated with decreased prevalence of steatohepatitis in patients with non-alcoholic fatty liver disease (NAFLD).J Hepatol. 2012; 57: 384-391Abstract Full Text Full Text PDF PubMed Scopus (212) Google Scholar This tool should be used at baseline and throughout the trial. To supplement the AUDIT-C, biochemistry markers such as phosphatidylethanol should be considered for confirming alcohol exposure. Further, the Lifetime Drinking History questionnaire or a similar interview protocol should be considered to assess lifetime alcohol consumption.13Friesema I.H. Veenstra M.Y. Zwietering P.J. et al.Measurement of lifetime alcohol intake: utility of a self-administered questionnaire.Am J Epidemiol. 2004; 159: 809-817Crossref PubMed Scopus (39) Google Scholar Tobacco use, such as smoking, should be considered to collect as a baseline parameter. Although clinical data are limited, tobacco has been associated with accelerated NAFLD pathogenesis.14Liu Y. Dai M. Bi Y. et al.Active smoking, passive smoking, and risk of nonalcoholic fatty liver disease (NAFLD): a population-based study in China.J Epidemiol. 2013; 23: 115-121Crossref PubMed Scopus (99) Google Scholar Further, marijuana use should also be assessed given evidence of cannabinoid modulation of liver steatosis and evidence suggesting acceleration of fibrosis and steatosis in chronic liver disease, such as hepatitis C.15Purohit V. Rapaka R. Shurtleff D. Role of cannabinoids in the development of fatty liver (steatosis).AAPS j. 2010; 12: 233-237Crossref PubMed Scopus (54) Google Scholar In that same light, over-the-counter medications and herbal supplements that may interfere with drug metabolism or impact liver function should also be captured. Concomitant medications such as statins, vitamin E, as well as medications used to treat diabetes or hypertension are essential to capture regardless of phase of trial or medication mechanism owing to potential confounding influence on outcomes (Supplementary Table 3). Such medications may have anti-NASH effects directly or indirectly by targeting elements of the metabolic syndrome. Therefore, it is important to have stable doses of such medications for ≥3 months before enrollment. Dose of medication and any dose changes during the study should be captured. Further, medications that may induce steatosis such as corticosteroids, amiodarone, and methotrexate should also be captured regardless of trial phase. Most of these medications lead to exclusion or may need to be considered for stratification. To the extent possible, absolute values should be used in reporting the results of laboratory tests instead of the use of threshold indicators or values relative to laboratory reference ranges (Tables 1 and 2). The metabolic panel should include fasting glucose, fasting insulin, and hemoglobin A1c regardless of trial phase or drug mechanism of action. Given the increased risk of the NASH phenotype among NAFLD patients with the metabolic syndrome, capturing these component elements in clinical trials is crucial, because their dynamics may be tied to drug action. The Homeostasis Model Assessment can be considered as a marker of insulin resistance in NAFLD. The glucose clamp technique to quantify insulin secretion and resistance is impractical when considering implementation across larger trials, but could be considered in early POC trials. Further, the oral glucose tolerance test minimal model may be considered in early POC trials because it provides a quantitative description of β-cell function and insulin sensitivity.16Breda E. Cavaghan M.K. Toffolo G. et al.Oral glucose tolerance test minimal model indexes of beta-cell function and insulin sensitivity.Diabetes. 2001; 50: 150-158Crossref PubMed Scopus (275) Google ScholarTable 1Metabolic PanelEarly Phase TrialsLate Phase TrialsFasting glucoseEEFasting insulinEEHemoglobin A1cEEHOMACCGlucose clampCNROGTTCCC, consider; E, essential; HOMA, homeostasis model assessment; NR, not recommended; OGTT, oral glucose tolerance test. Open table in a new tab Table 2Laboratory TestsEarly Phase TrialsLate Phase TrialsALTEEASTEEALPEETotal bilirubinEEDirect bilirubinEEGGTEEAlbuminEEProthrombin time or INREETotal cholesterolEELDL-CEEHDL-CEETSHEETriglyceridesEEHemoglobinEEHematocritEEPlateletsEEBUNEECreatinineEEUrine microalbuminCCFerritinIIALT, alanine aminotransferase; ALP, alkaline phosphatase; AST, aspartate aminotransferase; BUN, blood urea nitrogen; C, consider; E, essential; GGT, γ-glutamyl transpeptidase; HDL-C, high-density lipoprotein cholesterol; I, ideal; INR, International Normalized Ratio; LDL-C, low-density lipoprotein cholesterol; TSH, thyroid-stimulating hormone. Open table in a new tab C, consider; E, essential; HOMA, homeostasis model assessment; NR, not recommended; OGTT, oral glucose tolerance test. ALT, alanine aminotransferase; ALP, alkaline phosphatase; AST, aspartate aminotransferase; BUN, blood urea nitrogen; C, consider; E, essential; GGT, γ-glutamyl transpeptidase; HDL-C, high-density lipoprotein cholesterol; I, ideal; INR, International Normalized Ratio; LDL-C, low-density lipoprotein cholesterol; TSH, thyroid-stimulating hormone. Liver-related laboratory tests such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total and direct bilirubin, γ-glutamyl transpeptidase, albumin, and prothrombin time or International Normalized Ratio should be captured regardless of phase of trial or drug mechanism. At least 2 sets of laboratory tests should be captured several weeks apart to ensure stability before trial entry. If laboratory results show evidence of change, then a third set should be obtained to ensure suitability for trial entry. This is further important to track drug tolerability after a trial begins. Furthermore, dynamic changes to these values may occur owing to activity of the study drug or metabolites, and relative change may be used in the analysis of endpoints. Fasting lipids should also be measured at baseline, because these values may change owing to effect of a study drug. Hematologic tests are also important to capture to track potential drug-related adverse effects and to ensure suitability for inclusion. Further chemistries such as blood urea nitrogen and creatinine should also be obtained given potential influence of drug clearance. For trials enrolling cirrhotic patients, Model for End-stage Liver Disease-Na score and Child-Pugh score should be obtained. Liver histology is ideally captured for POC trials and is essential for later phase trials as the standard benchmark (Supplementary Table 4). We recommend all liver biopsy specimens be reviewed and scored according to the NASH CRN system with the overall histopathologic interpretation additionally documented.17Kleiner D.E. Brunt E.M. Van Natta M. et al.Design and validation of a histological scoring system for nonalcoholic fatty liver disease.Hepatology. 2005; 41: 1313-1321Crossref PubMed Scopus (7972) Google Scholar This scoring system has demonstrated good interrater reproducibility and specifies the degree of steatosis, lobular inflammation, and hepatocellular ballooning needed to calculate the NAFLD activity score and separately evaluates fibrosis stage. Major landmark trials in NASH have used this scoring system for histologic assessment, which allows for comparative analyses. A more recent evolution of this scoring system, the steatosis, activity, and fibrosis score, is semiquantitative.18Bedossa P. Utility and appropriateness of the fatty liver inhibition of progression (FLIP) algorithm and steatosis, activity, and fibrosis (SAF) score in the evaluation of biopsies of nonalcoholic fatty liver disease.Hepatology. 2014; 60: 565-575Crossref PubMed Scopus (477) Google Scholar This scoring system also has good interrater reproducibility and separates steatosis from necroinflammation ('activity'), 2 features that potentially have distinct prognostic implications. This distinction may assist in detection of therapeutic benefit where a treatment does not alter hepatic triglyceride accumulation. Because the 2 systems share much in common, it is advised that changes in the steatosis, activity, and fibrosis 'activity' domain be included as a secondary endpoint in future trials. Further recommendations regarding comorbidities and surgical history, anthropometrics, specialized biomarkers, and quality of life are available in the Supplement Materials. NASH is recognized as a major cause of chronic liver disease leading to cirrhosis, liver transplantation, and hepatocellular carcinoma. Evaluating potential therapies that lead to NASH resolution or prevent its progression is now the focus of multiple, ongoing clinical trials. The ability to compare the results of clinical trials for new therapeutics for NASH depends on the collection of a standardized set of essential parameters at baseline. This paper recommends an essential set of parameters that would allow patient cohorts recruited into different trials to be compared. We fully anticipate that these baseline parameters will continue to evolve over time as new knowledge accumulates with the completion of trials and the identification of new genetic and environment factors that contribute to the pathogenesis of NASH, liver fibrosis, and hepatocellular carcinoma. The authors gratefully acknowledge the support of the working group members (Appendix A), Myrna Cozen, Lauren Smith, and Katherine Greene for the work leading to the preparation of this manuscript. Quentin M. Anstee, PhD, FRCP, Newcastle University Medical School; Sander Bangma, MSc, DipMgt, Resonance Health; Melanie Baxter, Resonance Health; Sherif Boulos, PhD, Resonance Health; Gary Burgess, MBChB, MMed, Vectura Limited; Manu Chakravarthy, MD, PhD, Eli Lilly and Company; Rose Christian, MD, Bristol-Myers Squibb; Anthony Coombs, PhD, University of Oxford; David DeBrota, MD, Eli Lilly & Company; Lara Dimick-Santos, MD, US Food and Drug Administration; Claudia Filozof, MD, PhD, Covance; Goran Gannedahl, MD, PhD, AstraZeneca R&D; Richard Herrmann, MSc, VLVbio AB; Dean Hum, PhD, Genfit SA; Joanne Imperial, MD, Conatus Pharmaceuticals; Stuart Kendrick, MA, BMBCh, PhD, GlaxoSmithKline; Leigh MacConell, PhD, Intercept Pharmaceuticals; Sophie Megnien, MD, Genfit Corp.; Ruby Mehta, MD, US Food and Drug Administration; Veronica Miller, PhD, Forum for Collaborative HIV Research; Andrew Muir, MD, MHS, Duke University Medical Center; Brent A. Neuschwander-Tetri, MD, Saint Louis University School of Medicine; Yuval Patel, MD, Duke University Medical Center; Dan Peres, MD, Immuron Limited; Stephen Rossi, PharmD, NGM Biopharmaceuticals; Arun Sanyal, MBBS, MD, Virginia Commonwealth University; Elmer Schabel, MD, Bundesinstitut für Arzneimittel und Medizinprodukte; David Shapiro, MD, Intercept Pharmaceuticals; Tim St Pierre, PhD, Resonance Health; Michael Zemel, PhD, NuSirt Biopharma. The following comorbidities are essential to capture across all phases of trials and drug mechanisms: impaired glucose tolerance, type 2 diabetes mellitus, hypertension, hypercholesterolemia, hypertriglyceridemia, cardiovascular disease, chronic renal disease, obstructive sleep apnea, hypothyroidism, and autoimmune disease (Supplementary Table 5). These comorbidities are often found in nonalcoholic fatty liver disease (NAFLD) patients and are important to consider with regard to drug clearance, tolerability, and safety. Hypertension has been associated with fibrosis progression. Similarly, hypothyroidism is common in NAFLD, and treated and untreated status should be captured because the effects of thyroid hormone on metabolism and thermoregulation may impact disease severity and treatment response. Patients with untreated or uncontrolled hypothyroidism should not be eligible for trials because initiating thyroid replacement may confound results. In addition, chronic kidney disease is essential to capture owing to renal function effects on drug clearance and metabolism. Furthermore, some drugs may be more useful in certain subpopulations of patients with nonalcoholic steatohepatitis (NASH), such as those with type 2 diabetes mellitus or comorbid cardiovascular disease. Some proposed drugs may improve or eliminate types of comorbid disease, such as weight loss potentially benefiting patients with abdominal obesity and obstructive sleep apnea. Given the influence of other liver conditions on NAFLD-related outcomes, these parameters should be recorded at the onset. Capturing history of drug-induced liver injury and gastrointestinal disease and surgery is essential because these conditions may influence the ongoing pathophysiology of NAFLD. Drug-induced liver injury may aggravate preexisting NAFLD and conversely NAFLD patients are at increased risk to develop drug-induced liver injury.19Fromenty B. Drug-induced liver injury in obesity.J Hepatol. 2013; 58: 824-886Abstract Full Text Full Text PDF PubMed Scopus (78) Google Scholar Hepatitis C virus (HCV) infection has been associated with increased disease progression in NAFLD.20Blonsky J.J. Harrison S.A. Review article: nonalcoholic fatty liver disease and hepatitis C virus–partners in crime.Aliment Pharmacol Ther. 2008; 27: 855-865Crossref PubMed Scopus (27) Google Scholar NAFLD patients with a history of HCV exposure and spontaneously cleared HCV infection may be considered for eligibility. Although active HCV infection would be an exclusion criterion for NAFLD studies, patients with NAFLD diagnosed after successfully treated infection may be considered as a subgroup for exploration based on trial criteria specifying an adequate time duration after documented clearance. Other types of ongoing chronic liver disease would result in exclusion from NAFLD clinical trials and would be identified by history obtained during the screening process or may be uncovered at baseline biopsy. Gastrointestinal disease and surgical history such as cholelithiasis, cholecystectomy, and bariatric surgery would also be important to document because they may impact outcomes. For example, bariatric surgery not only results in rapid sustained weight loss, but has also been associated with significant improvement in NAFLD histologic severity.21Bower G. Toma T. Harling L. et al.Bariatric surgery and non-alcoholic fatty liver disease: a systematic review of liver biochemistry and histology.Obes Surg. 2015; 25: 2280-2289Crossref PubMed Scopus (181) Google Scholar As such, bariatric surgery should be an exclusion criterion for trial enrollment, although failed gastric banding patients may be considered eligible. Patients that have failed endoscopic bariatric treatment, such as with an intragastric balloon, may also be considered eligible. Anthropometric factors such as weight, ∗Weight should be measured in a standardized fashion on a calibrated scale with bare feet close together and a single layer of clothing. height, body mass index, waist circumference, †Waist circumference should be standardized as a measurement midway between the uppermost border of the iliac crest and the lower border of the costal margin. The tape should be placed around the abdomen at the level of this midway point and a reading taken when the tape is snug but does not compress the skin.22Obesity preventing and managing the global epidemic. Report of a WHO consultation.World Health Organ Tech Rep Ser. 2000; 894 (1–253): i-xiiPubMed Google Scholar and blood pressure are essential to capture for all trials (all phases and all interventions; Supplementary Table 6). Given the increased risk of the NASH phenotype among NAFLD patients with the metabolic syndrome, capturing these component elements in clinical trials is crucial, because their dynamics may be tied to drug action. For example, a particular drug may work by improving insulin resistance, and therefore these parameters may identify a particular type of comorbid NAFLD patient more likely to benefit. The relationship between weight trends, recency, and duration of obesity and NAFLD fibrosis severity and treatment response is not known. An attempt to gather information may help to establish the importance of history of obesity in treatment outcome. Other circumferential measurements to consider include neck, chest, hip, and midthigh. Further validation is required before specific biomarkers can be recommended for use in standardized baseline assessment in NASH clinical trials. At this time, the choice of biomarkers for a given trial should be considered primarily by the mechanism of action of the investigational drug and to optimize companion diagnostics development. A schematic representation of NAFLD disease processes with associated biomarkers is noted in Supplementary Figure 1. It will be incumbent on sponsors to collect further biomarker data to confirm mechanisms of action and/or for pharmacokinetic and pharmacodynamic modeling purposes. Measuring these biomarkers at baseline would allow for evaluation of anti-inflammatory or antifibrotic activity for the given drug by examining response. Furthermore, such biomarkers may show promise for clinical usefulness in measuring drug effect for future studies. The application of imaging technologies to NAFLD is a rapidly evolving field. Some modalities are informative for fat content, some for fibrosis; as of now, none are validated for assessing the degree of inflammation (Supplementary Table 7). Supplementary Table 8 lists these modalities with their potential applications. Evaluation of their strengths and weaknesses are included in a separate manuscript.23Siddiqui SHA, Abdelmalek MF, Anstee Q, et al. Case definitions for inclusion and analysis of endpoints in clinical trials for NASH through the lens of regulatory science. Hepatology (Under Review).Google Scholar The Liver Forum will continue to follow the evolution of all these tests in the evaluation of NASH and its treatment response, and develop recommendations as the science evolves. Inclusion of novel testing modalities in future trials may help to facilitate the evaluation of these tests in a systematic manner. No disease-specific quality-of-life instruments have been validated for regulatory purposes for NAFLD (Supplementary Table 8). Existing instruments such as the Short Form 36 and Patient-reported Outcomes Measurement Information System are available and recommended for use in phase III trials, and should be considered for earlier phases. The Short Form 36, which is a well-validated 36-item self-report measure, has been used by the NASH CRN to evaluate quality of life in NAFLD.24David K. Kowdley K.V. Unalp A. et al.Quality of life in adults with nonalcoholic fatty liver disease: baseline data from the nonalcoholic steatohepatitis clinical research network.Hepatology. 2009; 49: 1904-1912Crossref PubMed Scopus (129) Google Scholar The Patient-reported Outcomes Measurement Information System instrument accurately measures physical, mental, and social parameters and is rigorously validated across a wide range of chronic illnesses.25Cella D. Riley W. Stone A. et al.The Patient-Reported Outcomes Measurement Information System (PROMIS) developed and tested its first wave of adult self-reported health outcome item banks: 2005-2008.J Clin Epidemiol. 2010; 63: 1179-1194Abstract Full Text Full Text PDF PubMed Scopus (3173) Google Scholar Given the prevalence of fatigue in NAFLD patients and impact on quality of life, this instrument may be well-suited for use in this chronic disease population. Standardization of NAFLD-specific quality-of-life measures through the use of these instruments would allow for assessment of change in quality of life through the course of a trial and allow for comparability across trials. Further development is needed to develop valid disease-specific instruments. A stratified randomization strategy in NASH clinical trials would help to reduce the impact of key confounders in assessing outcomes of trial drugs. Such a strategy may protect against type I error, improve power in small trials, and facilitate subgroup and interim analyses. A guiding principle is to have balanced distribution of any stratification factor in each study arm, which becomes cumbersome as stratification schemes become more complex. Therefore, we advocate for a limited stratification strategy aided by standardization of baseline parameter data. Furthermore, the number of strata should consider the total number of patients enrolled. For marketing authorization trials typically enrolling >2000 patients, 3 dichotomized stratification variables should be considered: liver fibrosis stage (stage 2 vs stage 3 or stage 1 vs stage 2 and 3 for those trials enrolling stage 1), vitamin E supplementation ≥400 IU (yes or no), and diabetes mellitus (ye or no). Baseline body mass index would importantly be a necessary covariate. Weight loss is also important to evaluate as a covariate given potential confounding effects on outcomes. As such, we recommend subgroup analyses evaluating change in NAFLD histologic outcomes, namely, NASH resolution and/or improvement in fibrosis, by quantified weight loss.Supplementary Table 1Demographics and GeneticsEarly Phase TrialsLate Phase TrialsAgeEESexEEMenopausal status (women)EERaceIEEthnicityIEConsent and DNA banking for future analysisIECandidate gene genotyping (eg, PNPLA3)IEGenome-wide genetic analysisCIC, consider; E, essential; I, ideal. Open table in a new tab Supplementary Table 2Diet and LifestyleEarly Phase TrialsLate Phase TrialsDietary and activity counselingEEShort-term alcohol consumption (AUDIT-C)EELifetime alcohol consumption (LDH-q)CCAlcohol exposure (PEth)CCCaffeine intakeEETobacco useCCMarijuana useEEOver-the-counter medications and herbal supplementsEEAUDIT-C, Alcohol Use Disorders Identification Test; C, consider; E, essential; I, ideal; LDH-q, lactate dehydrogenase release; PEth, phosphatidylethanol. Open table in a new tab Supplementary Table 3Concomitant MedicationsaSome of these comedications are exclusionary, and require stability and/or stratification.Early Phase TrialsLate Phase TrialsCholesterol medications (statins, fibrates, niacin, fish oil)EEVitamin EEEDiabetes medications (insulin, metformin, DPP-4 inhibitors, GLP-1 agonists, meglitinides, SGLT2 inhibitors, sulfonylureas, thiazolidinediones)EEHypertension medications (ACEIs, ARBs, CCBs, beta blockers, alpha blockers, diuretics)EECorticosteroidsEEAmiodaroneEETamoxifenEEMethotrexateEEUrsodeoxycholic acidEEAnti-depressants (MAOIs, SSRIs, SNRIs, TCAs)EEOral contraceptivesEEThyroid supplementsEEACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor blocker; CCB, calcium channel blocker; DPP-4, dipeptidyl peptidase-4; E, essential; GLP-1, glucagon-like peptide-1; MAOI, monoamine oxidase inhibitor; SGLT2, sodium glucose cotransporter-2; SNRI, serotonin norepinephrine reuptake inhibitor; SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressant.a Some of these comedications are exclusionary, and require stability and/or stratification. Open table in a new tab Supplementary Table 4Liver HistologyEarly Phase Trials/Proof Of ConceptEarly Phase Trials/Dose Ranging StudiesLate Phase TrialsLiver HistologyIEEE, essential; I, ideal. Open table in a new tab Supplementary Table 5Comorbidities and Surgical HistoryaSome of these comorbidities are exclusionary.Early Phase TrialsLate Phase TrialsIFG or IGTEEType 2 diabetes mellitusEEHypothyroidismEEDepressionEEHypertensionEEHypercholesterolemiaEEHypertriglyceridemiaEECardiovascular diseaseEEObstructive sleep apneaEEChronic renal diseaseEEAutoimmune diseaseEEHistory of drug-induced liver injuryEEHistory of bariatric surgeryEEHistory of gastrointestinal disease and surgeryEEE, essential; IFG, impaired fasting glucose; IGT, impaired glucose tolerance.a Some of these comorbidities are exclusionary. Open table in a new tab Supplementary Table 6Anthropometrics and Blood PressureEarly Phase TrialsLate Phase TrialsWeightEEHeightEEBMIEEWaist circumferenceEENeck, chest, hips, mid-thigh circumferenceCCBlood pressureEEBMI, body mass index; C, consider; E, essential. Open table in a new tab Supplementary Table 7Imaging and Other Noninvasive DiagnosticsApplicationEarly Phase TrialsLate Phase TrialsMRI/MRSSteatosisE in POC trials with changes in liver fat as primary endpointNAMultiparametric MRISteatosisC (to enrich a population in a POC when biopsy confirmation is not available)Need further validationVCE/fibroscan/MREaCan provide information about liver stiffness and liver fat, although cost and generalized use is limited at present.FibrosisC (to enrich a population in a POC when biopsy confirmation is not available)I (early identification of patients progressing to cirrhosis)C, consider; E, essential; I, ideal; MRE, magnetic resonance elastography; MRI, magnetic resonance imaging; MRS, magnetic resonance spectroscopy; NA, not applicable; POC, proof of concept; VCE, video capsule endoscopy.a Can provide information about liver stiffness and liver fat, although cost and generalized use is limited at present. Open table in a new tab Supplementary Table 8Health Related Quality of LifeEarly Phase TrialsLate Phase TrialsShort Form-36CEPatient-reported outcomes measurement information systemCEC, consider; E, essential. Open table in a new tab C, consider; E, essential; I, ideal. AUDIT-C, Alcohol Use Disorders Identification Test; C, consider; E, essential; I, ideal; LDH-q, lactate dehydrogenase release; PEth, phosphatidylethanol. ACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor blocker; CCB, calcium channel blocker; DPP-4, dipeptidyl peptidase-4; E, essential; GLP-1, glucagon-like peptide-1; MAOI, monoamine oxidase inhibitor; SGLT2, sodium glucose cotransporter-2; SNRI, serotonin norepinephrine reuptake inhibitor; SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressant. E, essential; I, ideal. E, essential; IFG, impaired fasting glucose; IGT, impaired glucose tolerance. BMI, body mass index; C, consider; E, essential. C, consider; E, essential; I, ideal; MRE, magnetic resonance elastography; MRI, magnetic resonance imaging; MRS, magnetic resonance spectroscopy; NA, not applicable; POC, proof of concept; VCE, video capsule endoscopy. C, consider; E, essential. Biomarkers for Nonalcoholic SteatohepatitisGastroenterologyVol. 154Issue 5PreviewWe read with interest the article entitled "Baseline Parameters in Clinical Trials for Nonalcoholic Steatohepatitis: Recommendations From the Liver Forum" by Patel et al.1 We congratulate the authors on a very well-done and in-depth presentation of the potential biomarkers for nonalcoholic steatohepatitis. We support their conclusion that the presented tests may set the basis for a new era of follow-up of these patients in clinical trials. Some of these tests may become the standard of care in clinical practice. Full-Text PDF

Purpose: Time required in the trichobezoar formation. Methods: A 13-year-old African American female admitted to CHM in March 2004 with chief complains of abdominal pain. Admitting diagnosis was pancreatitis (amylase 266 and lipase 1039). Past medical history: positive for anxiety, depression, trichotillomania, pica and Iron deficiency anemia. She was on prozac, OCP, and started on griseofulvin for presumed Tinea capitis. In September 2003 she had an EGD which was consistent with esophagitis and gastritis. The patient continued complaining of abdominal pain, abdominal film showed a diffuse mass in the stomach and possibly in duodenum. An upper GI revealed a large bezoar in the stomach extending into proximal small bowel and dilatation of the small bowel more distally. The patient was taken to the operating room. The stomach and the small intestines were explored and a large mass of hair and particulate material was taken out. Grossly the trichobezoar consisted of multiple clumps of light to dark brown hair intermixed with a small amount of vegetative material. Post operative course was uneventful. The patient's lipase and amylase levels started normalizing and repeat abdominal X-ray was showed no evidence of mass. The patient was subsequently discharged to home. In August 2004 the patient was admitted again to CHM with three day history of emesis and abdominal pain. On physical examination an abdominal mass was palpated. An abdominal X-ray revealed a mass in the stomach, with possible extension to the duodenum. The patient was taken to the operating room and a trichobezoar was removed from her stomach and duodenum. Grossly the bezoar was multiple clumps of black and brown hair mixed with multiple pieces of tan and brown partially digested food particles. The patient had an uneventful recovery from the surgery and was discharged home. Results: The interesting finding in our case comes from the fact that there was time frame documentation for the trichobezoar formation on two occasions. The first bezoar developed within six months after endoscopy procedure and the second bezoar formation occurred four months after the removal of first gastric trichobezoar. The common notion is that the development of trichobezoar is a process that takes a long duration of time. To our knowledge there has been no previous documentation of the minimum period of time for the formation of a trichobezoar with a significant size to cause symptoms. Conclusion: One should therefore, have a high index of suspicion in a patient presenting with features suggestive of the trichobezoar even if the duration of symptoms is relatively short.