ABSTRACT
BACKGROUND: Dual agonism of glucagon receptor and glucagon-like peptide-1 (GLP-1) receptor may be more effective than GLP-1 receptor agonism alone for treating metabolic dysfunction-associated steatohepatitis (MASH). The efficacy and safety of survodutide (a dual agonist of glucagon receptor and GLP-1 receptor) in persons with MASH and liver fibrosis are unclear. METHODS: In this 48-week, phase 2 trial, we randomly assigned adults with biopsy-confirmed MASH and fibrosis stage F1 through F3 in a 1:1:1:1 ratio to receive once-weekly subcutaneous injections of survodutide at a dose of 2.4, 4.8, or 6.0 mg or placebo. The trial had two phases: a 24-week rapid-dose-escalation phase, followed by a 24-week maintenance phase. The primary end point was histologic improvement (reduction) in MASH with no worsening of fibrosis. Secondary end points included a decrease in liver fat content by at least 30% and biopsy-assessed improvement (reduction) in fibrosis by at least one stage. RESULTS: A total of 293 randomly assigned participants received at least one dose of survodutide or placebo. Improvement in MASH with no worsening of fibrosis occurred in 47% of the participants in the survodutide 2.4-mg group, 62% of those in the 4.8-mg group, and 43% of those in the 6.0-mg group, as compared with 14% of those in the placebo group (P<0.001 for the quadratic dose-response curve as best-fitting model). A decrease in liver fat content by at least 30% occurred in 63% of the participants in the survodutide 2.4-mg group, 67% of those in the 4.8-mg group, 57% of those in the 6.0-mg group, and 14% of those in the placebo group; improvement in fibrosis by at least one stage occurred in 34%, 36%, 34%, and 22%, respectively. Adverse events that were more frequent with survodutide than with placebo included nausea (66% vs. 23%), diarrhea (49% vs. 23%), and vomiting (41% vs. 4%); serious adverse events occurred in 8% with survodutide and 7% with placebo. CONCLUSIONS: Survodutide was superior to placebo with respect to improvement in MASH without worsening of fibrosis, warranting further investigation in phase 3 trials. (Funded by Boehringer Ingelheim; 1404-0043 ClinicalTrials.gov number, NCT04771273; EudraCT number, 2020-002723-11.).
Subject(s)
Glucagon-Like Peptide-1 Receptor , Liver Cirrhosis , Humans , Female , Male , Liver Cirrhosis/drug therapy , Middle Aged , Double-Blind Method , Adult , Glucagon-Like Peptide-1 Receptor/agonists , Injections, Subcutaneous/adverse effects , Fatty Liver/drug therapy , Liver/pathology , Liver/drug effects , Receptors, Glucagon/agonists , Dose-Response Relationship, Drug , AgedABSTRACT
BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a progressive liver disease with no approved treatment. Resmetirom is an oral, liver-directed, thyroid hormone receptor beta-selective agonist in development for the treatment of NASH with liver fibrosis. METHODS: We are conducting an ongoing phase 3 trial involving adults with biopsy-confirmed NASH and a fibrosis stage of F1B, F2, or F3 (stages range from F0 [no fibrosis] to F4 [cirrhosis]). Patients were randomly assigned in a 1:1:1 ratio to receive once-daily resmetirom at a dose of 80 mg or 100 mg or placebo. The two primary end points at week 52 were NASH resolution (including a reduction in the nonalcoholic fatty liver disease [NAFLD] activity score by ≥2 points; scores range from 0 to 8, with higher scores indicating more severe disease) with no worsening of fibrosis, and an improvement (reduction) in fibrosis by at least one stage with no worsening of the NAFLD activity score. RESULTS: Overall, 966 patients formed the primary analysis population (322 in the 80-mg resmetirom group, 323 in the 100-mg resmetirom group, and 321 in the placebo group). NASH resolution with no worsening of fibrosis was achieved in 25.9% of the patients in the 80-mg resmetirom group and 29.9% of those in the 100-mg resmetirom group, as compared with 9.7% of those in the placebo group (P<0.001 for both comparisons with placebo). Fibrosis improvement by at least one stage with no worsening of the NAFLD activity score was achieved in 24.2% of the patients in the 80-mg resmetirom group and 25.9% of those in the 100-mg resmetirom group, as compared with 14.2% of those in the placebo group (P<0.001 for both comparisons with placebo). The change in low-density lipoprotein cholesterol levels from baseline to week 24 was -13.6% in the 80-mg resmetirom group and -16.3% in the 100-mg resmetirom group, as compared with 0.1% in the placebo group (P<0.001 for both comparisons with placebo). Diarrhea and nausea were more frequent with resmetirom than with placebo. The incidence of serious adverse events was similar across trial groups: 10.9% in the 80-mg resmetirom group, 12.7% in the 100-mg resmetirom group, and 11.5% in the placebo group. CONCLUSIONS: Both the 80-mg dose and the 100-mg dose of resmetirom were superior to placebo with respect to NASH resolution and improvement in liver fibrosis by at least one stage. (Funded by Madrigal Pharmaceuticals; MAESTRO-NASH ClinicalTrials.gov number, NCT03900429.).
Subject(s)
Liver Cirrhosis , Non-alcoholic Fatty Liver Disease , Pyridazines , Uracil , Adult , Humans , Double-Blind Method , Liver/diagnostic imaging , Liver/drug effects , Liver/pathology , Liver Cirrhosis/drug therapy , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/pathology , Pyridazines/therapeutic use , Treatment Outcome , Uracil/analogs & derivatives , Thyroid Hormone Receptors beta/agonists , Biopsy , Dose-Response Relationship, DrugABSTRACT
Hepatocellular carcinoma (HCC) can have viral or non-viral causes1-5. Non-alcoholic steatohepatitis (NASH) is an important driver of HCC. Immunotherapy has been approved for treating HCC, but biomarker-based stratification of patients for optimal response to therapy is an unmet need6,7. Here we report the progressive accumulation of exhausted, unconventionally activated CD8+PD1+ T cells in NASH-affected livers. In preclinical models of NASH-induced HCC, therapeutic immunotherapy targeted at programmed death-1 (PD1) expanded activated CD8+PD1+ T cells within tumours but did not lead to tumour regression, which indicates that tumour immune surveillance was impaired. When given prophylactically, anti-PD1 treatment led to an increase in the incidence of NASH-HCC and in the number and size of tumour nodules, which correlated with increased hepatic CD8+PD1+CXCR6+, TOX+, and TNF+ T cells. The increase in HCC triggered by anti-PD1 treatment was prevented by depletion of CD8+ T cells or TNF neutralization, suggesting that CD8+ T cells help to induce NASH-HCC, rather than invigorating or executing immune surveillance. We found similar phenotypic and functional profiles in hepatic CD8+PD1+ T cells from humans with NAFLD or NASH. A meta-analysis of three randomized phase III clinical trials that tested inhibitors of PDL1 (programmed death-ligand 1) or PD1 in more than 1,600 patients with advanced HCC revealed that immune therapy did not improve survival in patients with non-viral HCC. In two additional cohorts, patients with NASH-driven HCC who received anti-PD1 or anti-PDL1 treatment showed reduced overall survival compared to patients with other aetiologies. Collectively, these data show that non-viral HCC, and particularly NASH-HCC, might be less responsive to immunotherapy, probably owing to NASH-related aberrant T cell activation causing tissue damage that leads to impaired immune surveillance. Our data provide a rationale for stratification of patients with HCC according to underlying aetiology in studies of immunotherapy as a primary or adjuvant treatment.
Subject(s)
Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Immunotherapy , Liver Neoplasms/immunology , Liver Neoplasms/therapy , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/immunology , Animals , B7-H1 Antigen/immunology , B7-H1 Antigen/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Carcinogenesis/immunology , Carcinoma, Hepatocellular/complications , Carcinoma, Hepatocellular/immunology , Disease Progression , Humans , Liver/immunology , Liver/pathology , Liver Neoplasms/complications , Liver Neoplasms/pathology , Male , Mice , Non-alcoholic Fatty Liver Disease/pathology , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/immunology , Programmed Cell Death 1 Receptor/metabolism , Tumor Necrosis Factor-alpha/immunologyABSTRACT
BACKGROUND: Pegozafermin is a long-acting glycopegylated (pegylated with the use of site-specific glycosyltransferases) fibroblast growth factor 21 (FGF21) analogue in development for the treatment of nonalcoholic steatohepatitis (NASH) and severe hypertriglyceridemia. The efficacy and safety of pegozafermin in patients with biopsy-proven noncirrhotic NASH are not well established. METHODS: In this phase 2b, multicenter, double-blind, 24-week, randomized, placebo-controlled trial, we randomly assigned patients with biopsy-confirmed NASH and stage F2 or F3 (moderate or severe) fibrosis to receive subcutaneous pegozafermin at a dose of 15 mg or 30 mg weekly or 44 mg once every 2 weeks or placebo weekly or every 2 weeks. The two primary end points were an improvement in fibrosis (defined as reduction by ≥1 stage, on a scale from 0 to 4, with higher stages indicating greater severity), with no worsening of NASH, at 24 weeks and NASH resolution without worsening of fibrosis at 24 weeks. Safety was also assessed. RESULTS: Among the 222 patients who underwent randomization, 219 received pegozafermin or placebo. The percentage of patients who met the criteria for fibrosis improvement was 7% in the pooled placebo group, 22% in the 15-mg pegozafermin group (difference vs. placebo, 14 percentage points; 95% confidence interval [CI], -9 to 38), 26% in the 30-mg pegozafermin group (difference, 19 percentage points; 95% CI, 5 to 32; P = 0.009), and 27% in the 44-mg pegozafermin group (difference, 20 percentage points; 95% CI, 5 to 35; P = 0.008). The percentage of patients who met the criteria for NASH resolution was 2% in the placebo group, 37% in the 15-mg pegozafermin group (difference vs. placebo, 35 percentage points; 95% CI, 10 to 59), 23% in the 30-mg pegozafermin group (difference, 21 percentage points; 95% CI, 9 to 33), and 26% in the 44-mg pegozafermin group (difference, 24 percentage points; 95% CI, 10 to 37). The most common adverse events associated with pegozafermin therapy were nausea and diarrhea. CONCLUSIONS: In this phase 2b trial, treatment with pegozafermin led to improvements in fibrosis. These results support the advancement of pegozafermin into phase 3 development. (Funded by 89bio; ENLIVEN ClinicalTrials.gov number, NCT04929483.).
Subject(s)
Fibroblast Growth Factors , Fibrosis , Gastrointestinal Agents , Non-alcoholic Fatty Liver Disease , Humans , Biopsy , Double-Blind Method , Fibroblast Growth Factors/analogs & derivatives , Fibrosis/drug therapy , Fibrosis/etiology , Fibrosis/pathology , Gastrointestinal Agents/administration & dosage , Gastrointestinal Agents/therapeutic use , Injections, Subcutaneous , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/pathology , Treatment OutcomeABSTRACT
BACKGROUND & AIMS: In non-alcoholic fatty liver disease (NAFLD), monocytes infiltrate visceral adipose tissue promoting local and hepatic inflammation. However, it remains unclear what drives inflammation and how the immune landscape in adipose tissue differs across the NAFLD severity spectrum. We aimed to assess adipose tissue macrophage (ATM) heterogeneity in a NAFLD cohort. METHODS: Visceral adipose tissue macrophages from lean and obese patients, stratified by NAFLD phenotypes, underwent single-cell RNA sequencing. Adipose tissue vascular integrity and breaching was assessed on a protein level via immunohistochemistry and immunofluorescence to determine targets of interest. RESULTS: We discovered multiple ATM populations, including resident vasculature-associated macrophages (ResVAMs) and distinct metabolically active macrophages (MMacs). Using trajectory analysis, we show that ResVAMs and MMacs are replenished by a common transitional macrophage (TransMac) subtype and that, during NASH, MMacs are not effectively replenished by TransMac precursors. We postulate an accessory role for MMacs and ResVAMs in protecting the adipose tissue vascular barrier, since they both interact with endothelial cells and localize around the vasculature. However, across the NAFLD severity spectrum, alterations occur in these subsets that parallel an adipose tissue vasculature breach characterized by albumin extravasation into the perivascular tissue. CONCLUSIONS: NAFLD-related macrophage dysfunction coincides with a loss of adipose tissue vascular integrity, providing a plausible mechanism by which tissue inflammation is perpetuated in adipose tissue and downstream in the liver. IMPACT AND IMPLICATIONS: Our study describes for the first time the myeloid cell landscape in human visceral adipose tissue at single-cell level within a cohort of well-characterized patients with non-alcoholic fatty liver disease. We report unique non-alcoholic steatohepatitis-specific transcriptional changes within metabolically active macrophages (MMacs) and resident vasculature-associated macrophages (ResVAMs) and we demonstrate their spatial location surrounding the vasculature. These dysfunctional transcriptional macrophage states coincided with the loss of adipose tissue vascular integrity, providing a plausible mechanism by which tissue inflammation is perpetuated in adipose tissue and downstream in the liver. Our study provides a theoretical basis for new therapeutic strategies to be directed towards reinstating the endogenous metabolic, homeostatic and cytoprotective functions of ResVAMs and MMacs, including their role in protecting vascular integrity.
Subject(s)
Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/complications , Endothelial Cells/metabolism , Liver/metabolism , Macrophages/metabolism , Adipose Tissue/metabolism , Inflammation/metabolismABSTRACT
BACKGROUND & AIMS: Non-invasive scores have been proposed to identify patients with fibrotic, metabolic dysfunction-associated steatohepatitis (MASH), who are at the highest risk of progression to complications of cirrhosis and may benefit from pharmacologic treatments. However, data in patients with type 2 diabetes (T2DM) are lacking. The aim of this multicenter prospective study was to perform a head-to-head comparison of FAST (FibroScan-aspartate aminotransferase [AST]), MAST (MRI-AST), MEFIB (magnetic resonance elastography [MRE] plus FIB-4), and FNI (fibrotic NASH index) for detecting fibrotic MASH in patients with T2DM. METHODS: A total of 330 outpatients with T2DM and biopsy-proven metabolic dysfunction-associated steatotic liver disease (MASLD) from the QUID-NASH study (NCT03634098), who underwent FibroScan, MRI-proton density fat fraction and MRE at the time of liver biopsy were studied. The main outcome was fibrotic MASH, defined as NAS ≥4 (with at least one point for each parameter) and fibrosis stage ≥2 (centrally reviewed). RESULTS: All data for score comparisons were available for 245 patients (median age 59 years, 65% male, median BMI 31 kg/m2; fibrotic MASH in 39%). FAST and MAST had similar accuracy (AUROCs 0.81 vs. 0.79, p = 0.41) but outperformed FNI (0.74; p = 0.01) and MEFIB (0.68; p <0.0001). When using original cut-offs, MAST outperformed FAST, MEFIB and FNI when comparing the percentage of correctly classified patients, in whom liver biopsy would be avoided (69% vs. 48%, 46%, 39%, respectively; p <0.001). When using cut-offs specific to our population, FAST outperformed FNI and MAST (56% vs. 40%, and 38%, respectively; p <0.001). CONCLUSION: Our findings show that FAST, MAST, MEFIB and FNI are accurate non-invasive tools to identify patients with T2DM and fibrotic MASH in secondary/tertiary diabetes clinics. Cut-offs adapted to the T2DM population should be considered. IMPACT AND IMPLICATIONS: Among patients with type 2 diabetes (T2DM), identifying those with metabolic dysfunction-associated steatohepatitis and significant fibrosis, who are the most at risk of developing clinical liver-related outcomes and who may benefit from pharmacologic treatments, is an unmet need. In this prospective multicenter study, we compared four non-invasive scores, three based on imaging (MRI or ultrasound technologies) and one on laboratory blood tests, for this purpose, using original and study-specific cut-offs. Our findings show that FAST, MAST, MEFIB and FNI are accurate non-invasive tools to identify patients with T2DM and fibrotic MASH in secondary/tertiary diabetes clinics. Cut-offs adapted to the T2DM population should be considered. TRIAL REGISTRATION NUMBER: NCT03634098.
Subject(s)
Diabetes Mellitus, Type 2 , Elasticity Imaging Techniques , Liver Cirrhosis , Magnetic Resonance Imaging , Humans , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnosis , Male , Middle Aged , Female , Prospective Studies , Elasticity Imaging Techniques/methods , Liver Cirrhosis/diagnosis , Liver Cirrhosis/etiology , Magnetic Resonance Imaging/methods , Aged , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/diagnosis , Biopsy/methods , Liver/pathology , Liver/diagnostic imaging , Aspartate Aminotransferases/bloodABSTRACT
The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) is increasing, and translational animal models are needed to develop novel treatments for this disease. The physiology and metabolism of pigs have a relatively high resemblance to humans, and the present study aimed to characterise choline-deficient, and high-fat diet (CDAHFD) fed Göttingen Minipigs as a novel animal model of MASLD/MASH. Göttingen Minipigs were fed CDAHFD for up to 5 months, and the phenotype was investigated by analysis of plasma parameters and repeated collection of liver biopsies. Furthermore, changes in hepatic gene expression during the experiment were explored by RNA sequencing. For a subset of the minipigs, the diet was changed from CDAHFD back to chow to investigate if the liver pathology was reversible. Göttingen Minipigs on CDAHFD gained bodyweight, and plasma levels of cholesterol, AST, ALT, ALP and GGT were increased. CDAHFD-fed minipigs developed hepatic steatosis, inflammation, and fibrosis, which in 5 of 16 animals progressed to cirrhosis. During an 11-week chow reversal period, steatosis regressed while fibrosis persisted. Regarding inflammation, the findings were less clear, depending on the type of readout. MASH Human Proximity Scoring (combined evaluation of transcriptional, phenotypic and histopathological parameters) showed that CDAHFD-fed Göttingen Minipigs resemble human MASLD/MASH better than most rodent models. In conclusion, CDAHFD-fed minipigs develop a MASH-like phenotype which in several aspects resemble the changes observed in human patients with MASLD/MASH. Furthermore, repeated collection of liver biopsies allow detailed characterisation of histopathological changes over time in individual animals.
ABSTRACT
BACKGROUND: Management of nonalcoholic steatohepatitis (NASH) is an unmet clinical need. Lanifibranor is a pan-PPAR (peroxisome proliferator-activated receptor) agonist that modulates key metabolic, inflammatory, and fibrogenic pathways in the pathogenesis of NASH. METHODS: In this phase 2b, double-blind, randomized, placebo-controlled trial, patients with noncirrhotic, highly active NASH were randomly assigned in a 1:1:1 ratio to receive 1200 mg or 800 mg of lanifibranor or placebo once daily for 24 weeks. The primary end point was a decrease of at least 2 points in the SAF-A score (the activity part of the Steatosis, Activity, Fibrosis [SAF] scoring system that incorporates scores for ballooning and inflammation) without worsening of fibrosis; SAF-A scores range from 0 to 4, with higher scores indicating more-severe disease activity. Secondary end points included resolution of NASH and regression of fibrosis. RESULTS: A total of 247 patients underwent randomization, of whom 103 (42%) had type 2 diabetes mellitus and 188 (76%) had significant (moderate) or advanced fibrosis. The percentage of patients who had a decrease of at least 2 points in the SAF-A score without worsening of fibrosis was significantly higher among those who received the 1200-mg dose, but not among those who received the 800-mg dose, of lanifibranor than among those who received placebo (1200-mg dose vs. placebo, 55% vs. 33%, P = 0.007; 800-mg dose vs. placebo, 48% vs. 33%, P = 0.07). The results favored both the 1200-mg and 800-mg doses of lanifibranor over placebo for resolution of NASH without worsening of fibrosis (49% and 39%, respectively, vs. 22%), improvement in fibrosis stage of at least 1 without worsening of NASH (48% and 34%, respectively, vs. 29%), and resolution of NASH plus improvement in fibrosis stage of at least 1 (35% and 25%, respectively, vs. 9%). Liver enzyme levels decreased and the levels of the majority of lipid, inflammatory, and fibrosis biomarkers improved in the lanifibranor groups. The dropout rate for adverse events was less than 5% and was similar across the trial groups. Diarrhea, nausea, peripheral edema, anemia, and weight gain occurred more frequently with lanifibranor than with placebo. CONCLUSIONS: In this phase 2b trial involving patients with active NASH, the percentage of patients who had a decrease of at least 2 points in the SAF-A score without worsening of fibrosis was significantly higher with the 1200-mg dose of lanifibranor than with placebo. These findings support further assessment of lanifibranor in phase 3 trials. (Funded by Inventiva Pharma; NATIVE ClinicalTrials.gov number, NCT03008070.).
Subject(s)
Benzothiazoles/therapeutic use , Liver Cirrhosis/drug therapy , Non-alcoholic Fatty Liver Disease/drug therapy , Peroxisome Proliferator-Activated Receptors/agonists , Sulfonamides/therapeutic use , Benzothiazoles/administration & dosage , Benzothiazoles/adverse effects , Body Mass Index , Diabetes Mellitus, Type 2/complications , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Liver Cirrhosis/etiology , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/etiology , Severity of Illness Index , Sulfonamides/administration & dosage , Sulfonamides/adverse effectsABSTRACT
BACKGROUND AND AIMS: Cenicriviroc (CVC) is a novel, orally administered, chemokine receptor type 2 and 5 antagonist that showed antifibrotic potential in preclinical and phase IIb studies of nonalcoholic steatohepatitis (NASH). Herein, we report efficacy and safety results from the phase III study. METHODS: The AURORA (A Study for the Efficacy and Safety of CVC for the Treatment of Liver Fibrosis in Adults With NASH) study was a phase III, randomized, double-blind, placebo-controlled, 2-part study of patients with NASH and stage 2/3 liver fibrosis. Adults, 18-75 years of age, were randomized to CVC 150 mg or placebo once daily for 12 months (part 1) or 60 months (part 2). Liver biopsies were performed at screening, month 12, and early study discontinuation or termination. The primary efficacy endpoint was the proportion of patients with fibrosis improvement ≥1 stage without worsening of steatohepatitis at month 12 relative to screening. Adverse events were assessed throughout the study. RESULTS: A total of 1778 patients were randomized and discontinued (part 1: n = 1293; part 2: n = 485). In part 1, at month 12, a similar proportion of patients receiving CVC or placebo achieved the primary endpoint (22.3% vs 25.5%; odds ratio, 0.84; 95% confidence interval, 0.63-1.10; P = .21) and complete resolution of steatohepatitis without worsening of fibrosis (23.0% vs 27.2%; P = .21). The safety profile was generally comparable across treatment groups. CONCLUSIONS: This study did not demonstrate the efficacy of CVC for treating liver fibrosis assessed by histology in adults with NASH; however, CVC was safe and well tolerated in patients with NASH and liver fibrosis. (ClinicalTrials.gov, Number: NCT03028740).
Subject(s)
Non-alcoholic Fatty Liver Disease , Adult , Humans , Child , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/pathology , Liver Cirrhosis/complications , Liver Cirrhosis/drug therapy , Liver Cirrhosis/pathology , Imidazoles , Fibrosis , Double-Blind Method , Liver/pathology , Treatment OutcomeABSTRACT
BACKGROUND AND AIMS: Detecting NASH remains challenging, while at-risk NASH (steatohepatitis and F≥ 2) tends to progress and is of interest for drug development and clinical application. We developed prediction models by supervised machine learning techniques, with clinical data and biomarkers to stage and grade patients with NAFLD. APPROACH AND RESULTS: Learning data were collected in the Liver Investigation: Testing Marker Utility in Steatohepatitis metacohort (966 biopsy-proven NAFLD adults), staged and graded according to NASH CRN. Conditions of interest were the clinical trial definition of NASH (NAS ≥ 4;53%), at-risk NASH (NASH with F ≥ 2;35%), significant (F ≥ 2;47%), and advanced fibrosis (F ≥ 3;28%). Thirty-five predictors were included. Missing data were handled by multiple imputations. Data were randomly split into training/validation (75/25) sets. A gradient boosting machine was applied to develop 2 models for each condition: clinical versus extended (clinical and biomarkers). Two variants of the NASH and at-risk NASH models were constructed: direct and composite models.Clinical gradient boosting machine models for steatosis/inflammation/ballooning had AUCs of 0.94/0.79/0.72. There were no improvements when biomarkers were included. The direct NASH model produced AUCs (clinical/extended) of 0.61/0.65. The composite NASH model performed significantly better (0.71) for both variants. The composite at-risk NASH model had an AUC of 0.83 (clinical and extended), an improvement over the direct model. Significant fibrosis models had AUCs (clinical/extended) of 0.76/0.78. The extended advanced fibrosis model (0.86) performed significantly better than the clinical version (0.82). CONCLUSIONS: Detection of NASH and at-risk NASH can be improved by constructing independent machine learning models for each component, using only clinical predictors. Adding biomarkers only improved the accuracy of fibrosis.
Subject(s)
Non-alcoholic Fatty Liver Disease , Adult , Humans , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/pathology , Liver/pathology , Fibrosis , Algorithms , Biomarkers , Machine Learning , Biopsy , Liver Cirrhosis/diagnosis , Liver Cirrhosis/pathologyABSTRACT
Liver biopsies have consistently contributed to our understanding of the pathogenesis and aetiologies of acute liver disease. As other diagnostic modalities have been developed and refined, the role of biopsy in the management of patients with acute liver failure (ALF), acute-on-chronic liver failure (ACLF) and acute hepatitis, including acute liver injury (ALI), has changed. Liver biopsy remains particularly valuable when first-line diagnostic algorithms fail to determine aetiology. Despite not being identified as a mandatory diagnostic tool in recent clinical guidelines for the management of ALF or ACLF, many centres continue to undertake biopsies given the relative safety of transjugular biopsy in this setting. Several studies have demonstrated that liver biopsy can provide prognostic information, particularly in the context of so-called indeterminate hepatitis, and is extremely useful in excluding conditions such as metastatic tumours that would preclude transplantation. In addition, its widespread use of percutaneous biopsies in cases of less severe acute liver injury, for example in the establishment of a diagnosis of acute presentation of autoimmune hepatitis or confirmation of a probable or definite drug-induced liver injury (DILI), has meant that many centres have seen a shift in the ratio of specimens they are receiving from patients with chronic to acute liver disease. Histopathologists therefore need to be equipped to deal with these challenging specimens. This overview provides an insight into the contemporary role of biopsies (as well as explant and autopsy material) in diagnosing acute liver disease. It outlines up-to-date clinical definitions of liver injury and considers recent recommendations for the diagnosis of AIH and drug-induced, autoimmune-like hepatitis (DI-AIH).
ABSTRACT
BACKGROUND & AIMS: Pioglitazone (Pio) is efficacious in NASH, but its utility is limited by PPARγ-driven side effects. Pio is a mixture of two enantiomers (R, S). PXL065, deuterium-stabilized R-Pio, lacks PPARγ activity but retains non-genomic activity. We tested the hypothesis that PXL065 would have similar efficacy but a better safety profile than Pio in patients with NASH. METHODS: Patients (≥8% liver fat, NAFLD activity score [NAS] ≥4, F1-F3) received daily doses of PXL065 (7.5, 15, 22.5 mg) or placebo 1:1:1:1 for 36 weeks. The primary endpoint was relative % change in liver fat content (LFC) on MRI-proton density fat fraction; liver histology, non-invasive tests, safety-tolerability, and pharmacokinetics were also assessed. RESULTS: One hundred and seventeen patients were evaluated. All PXL065 groups met the primary endpoint (-21 to -25% LFC, p = 0.008-0.02 vs. placebo); 40% (22.5 mg) achieved a ≥30% LFC reduction. Favorable trends in non-invasive tests including reductions in PIIINP (p = 0.02, 22.5 mg) and NAFLD fibrosis score (p = 0.04, 22.5 mg) were observed. On histology (n = 92), a ≥1 stage fibrosis improvement occurred in 40% (7.5 mg), 50% (15 mg, p = 0.06), and 35% (22.5 mg) vs. 17% for placebo; up to 50% of PXL065-treated patients achieved a ≥2 point NAS improvement without fibrosis worsening vs. 30% with placebo. Metabolic improvements included: HbA1c (-0.41% p = 0.003) and insulin sensitivity (HOMA-IR, p = 0.04; Adipo-IR, p = 0.002). Adiponectin increased (+114%, 22.5 mg, p <0.0001) vs. placebo. There was no dose-dependent effect on body weight or PXL065-related peripheral oedema signal. Overall, PXL065 was safe and well tolerated. Pharmacokinetics confirmed dose-proportional and higher steady state R- vs. S-Pio exposure. IMPACT AND IMPLICATIONS: Pioglitazone (Pio) is an approved diabetes medicine with proven efficacy in non-alcoholic steatohepatitis (NASH); PXL065 is a novel related oral agent which has been shown to retain Pio's efficacy in preclinical NASH models, with reduced potential for PPARγ-driven side effects. Results of this phase II study are important as PXL065 improved several key NASH disease features with a favorable safety profile - these findings can be applied by researchers seeking to understand pathophysiology and to develop new therapies. These results also indicate that PXL065 warrants further clinical testing in a pivotal NASH trial. Other implications include the potential future availability of a distinct oral therapy for NASH that may be relevant for patients, providers and caregivers seeking to prevent the progression and complications of this disease. CONCLUSIONS: PXL065 is a novel molecule which retains an efficacy profile in NASH similar to Pio with reduced potential for PPARγ-driven side effects. A pivotal clinical trial is warranted to confirm the histological benefits reported herein. IMPACT AND IMPLICATIONS: Pioglitazone (Pio) is an approved diabetes medicine with proven efficacy in non-alcoholic steatohepatitis (NASH); PXL065 is a novel related oral agent which has been shown to retain Pio's efficacy in preclinical NASH models, with reduced potential for PPARγ-driven side effects. Results of this phase II study are important as PXL065 improved several key NASH disease features with a favorable safety profile - these findings can be applied by researchers seeking to understand pathophysiology and to develop new therapies. These results also indicate that PXL065 warrants further clinical testing in a pivotal NASH trial. Other implications include the potential future availability of a distinct oral therapy for NASH that may be relevant for patients, providers and caregivers seeking to prevent the progression and complications of this disease.
Subject(s)
Diabetes Mellitus , Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/complications , Pioglitazone/therapeutic use , Deuterium/metabolism , Deuterium/therapeutic use , PPAR gamma , Liver/pathology , Fibrosis , Diabetes Mellitus/metabolism , Double-Blind MethodABSTRACT
BACKGROUND & AIMS: Similarly to the controlled attenuation parameter (CAP), the ultrasound-based attenuation imaging (ATI) can quantify hepatic steatosis. We prospectively compared the performance of ATI and CAP for the diagnosis of hepatic steatosis in patients with type 2 diabetes and nonalcoholic fatty liver disease using histology and magnetic resonance imaging-proton density fat fraction (MRI-PDFF) as references. METHODS: Patients underwent ATI and CAP measurement, MRI, and biopsy on the same day. Steatosis was classified as S0, S1, S2, and S3 on histology (<5%, 5%-33%, 33%-66%, and >66%, respectively) while the thresholds of 6.4%, 17.4%, and 22.1%, respectively, were used for MRI-PDFF. The area under the curve (AUC) of ATI and CAP was compared using a DeLong test. RESULTS: Steatosis could be evaluated in 191 and 187 patients with MRI-PDFF and liver biopsy, respectively. For MRI-PDFF steatosis, the AUC of ATI and CAP were 0.86 (95% confidence interval [CI], 0.81-0.91) vs 0.69 (95% CI, 0.62-0.75) for S0 vs S1-S3 (P = .02) and 0.71 (95% CI, 0.64-0.77) vs 0.69 (95% CI, 0.61-0.75) for S0-S1 vs S2-S3 (P = .60), respectively. For histological steatosis, the AUC of ATI and CAP were 0.92 (95% CI, 0.87-0.95) vs 0.95 (95% CI, 0.91-0.98) for S0 vs S1-S3 (P = .64) and 0.79 (95% CI, 0.72-0.84) vs 0.76 (95% CI, 0.69-0.82) for S0-S1 vs S2-S3 (P = .61), respectively. CONCLUSION: ATI may be used as an alternative to CAP for the diagnosis and quantification of steatosis, in patients with type 2 diabetes and nonalcoholic fatty liver disease.
ABSTRACT
BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is a growing concern in the aging population with human immunodeficiency virus (HIV). Screening for NAFLD is recommended in patients with metabolic risk factors or unexplained transaminitis. This study aimed to prospectively assess the prevalence and associated factors of liver steatosis and advanced fibrosis (AF) in HIV-monoinfected patients at risk of NAFLD. METHODS: We conducted a multicenter study in HIV-monoinfected patients, nonexcessive drinkers with metabolic syndrome, and/or persistently elevated liver enzymes, and/or clinical lipodystrophy. All participants had magnetic resonance imaging proton density fat fraction (MRI-PDFF), Fibroscan/controlled attenuation parameter (CAP), and cytokine and genetic analysis. RESULTS: From March 2014 to November 2015, we enrolled 442 participants and analyzed 402: male (85%); median age, 55 years (interquartile range [IQR], 50-61 years); body mass index, 27.0 kg/m2 (IQR, 23.6-28.7 kg/m2); metabolic syndrome (67%); and CD4 cell count, 630/mm3 (IQR, 510-832/mm3). Overall 257 of 402 (64%) had NAFLD (MRI-PDFF ≥5%). Among them, 11.3% had a liver stiffness ≥9.6 kPa, suggestive of AF. Multivariable analysis identified 7 factors of steatosis: high CD4-cell count (odds ratio [OR], 4.04; 95% confidence interval [CI], 1.92-8.51), high leptin level (OR, 2.12; 95% CI, 1.14-3.93), non-CC PNPLA3s738409 genetic polymorphism (OR, 1.92; 95% CI, 1.11-3.33), low high-density lipoprotein (OR, 1.83; 95% CI, 1.03-3.27), high triglycerides (OR, 1.48; 95% CI, 1.18-1.84), elevated alanine transaminase (OR, 1.23; 95% CI, 1.16-1.31), and hyper ferritinemia (OR, 1.05; 95% CI, 1.03-1.07). Two factors were associated with AF: high body mass index (OR, 1.23 ; 95% CI, 1.07-1.42 ; P = .005, and elevated aspartate aminotransferase (OR, 1.03; 95% CI, 1.01-1.05; P = .001). Using MRI-PDFF as a reference, CAP (best cutoff, 280 dB/m) had good accuracy (area under the receiver operating characteristic curve = 0.86; 95% CI, 0.82-0.90) for the diagnosis of moderate to severe steatosis. CONCLUSIONS: In a large cohort of HIV-moninfected patients at risk of NAFLD, steatosis is present in two-thirds of cases, and around 10% have AF. The CAP technique is accurate for screening steatosis in this population.
Subject(s)
Elasticity Imaging Techniques , HIV Infections , Metabolic Syndrome , Non-alcoholic Fatty Liver Disease , Aged , Humans , Male , Middle Aged , Elasticity Imaging Techniques/methods , HIV , HIV Infections/complications , Liver/pathology , Magnetic Resonance Imaging/methods , Metabolic Syndrome/complications , Non-alcoholic Fatty Liver Disease/complications , Prospective Studies , Protons , FemaleABSTRACT
BACKGROUND AND AIMS: It remains unclear to what extent and which components of advanced liver disease improve after bariatric surgery. We herein describe the histological outcome in patients with advanced NASH and its relationship with weight loss and metabolic improvement. APPROACH AND RESULTS: One hundred ninety-six patients with advanced NASH underwent bariatric surgery, 66 of whom agreed to a follow-up liver biopsy at 6 ± 3 years (36 with advanced fibrosis [AF] and 30 with high activity [HA] grade without AF). Liver biopsies LBs were centrally read and histological response was defined as the disappearance of AF or HA. Bariatric surgery induced major histological improvement: 29% of patients had normal histology at follow-up biopsy; 74% had NASH resolution without fibrosis progression; and 70% had ≥1 stage fibrosis regression. However, AF persisted in 47% of patients despite NASH resolution and some degree of fibrosis reversal, only evidenced by the EPoS seven-tier staging classification. These patients had lower weight loss and reduced hypertension or diabetes remission rates. Older age and sleeve gastrectomy were the only independent predictors for persistent AF after adjustment for duration of follow-up. All HA patients had major histological improvement: 50% normal histology, 80% NASH resolution, and 86% a ≥1 grade steatosis reduction. Patients with normal liver at follow-up had the largest weight loss and metabolic improvement. Independent predictors of normal liver were amount of weight loss, high histological activity, and the absence of AF before surgery. CONCLUSIONS: Although bariatric surgery successfully reverses active steatohepatitis, AF can persist for many years and is associated with lesser weight loss and metabolic improvement. Weight loss alone may not be sufficient to reverse AF.
Subject(s)
Bariatric Surgery , Non-alcoholic Fatty Liver Disease , Obesity, Morbid , Biopsy , Fibrosis , Humans , Liver/pathology , Liver Cirrhosis/complications , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/pathology , Non-alcoholic Fatty Liver Disease/surgery , Obesity, Morbid/complications , Obesity, Morbid/surgery , Weight LossABSTRACT
Non-alcoholic steatohepatitis (NASH) results from the accumulation of excessive liver lipids leading to hepatocellular injury, inflammation, and fibrosis that greatly increase the risk for hepatocellular carcinoma (HCC). Despite the well-characterized clinical and histological pathology for NASH-driven HCC in humans, its etiology remains unclear and there is a deficiency in pre-clinical models that recapitulate the progression of the human disease. Therefore, we developed a new mouse model amenable to genetic manipulations and gene targeting that mimics the gradual NASH to HCC progression observed in humans. C57BL/6NJ mice were fed a Western high-fat diet and sugar water (HFD/SW) and monitored for effects on metabolism, liver histology, tumor development, and liver transcriptome for up to 54 weeks. Chronic HFD/SW feeding led to significantly increased weight gain, serum and liver lipid levels, liver injury, and glucose intolerance. Hepatic pathology progressed and mice developed hepatocellular ballooning, inflammation, and worse fibrosis was apparent at 16 weeks, greatly increased through 32 weeks, and remained elevated at 54 weeks. Importantly, hepatocellular cancer spontaneously developed in 75% of mice on HFD/SW, half of which were HCC, whereas none of the mice on the chow diet developed HCC. Chronic HFD/SW induced molecular markers of de novo lipogenesis, endoplasmic reticulum stress, inflammation, and accumulation of p62, all of which also participate in the human pathology. Moreover, transcriptome analysis revealed activation of HCC-related genes and signatures associated with poor prognosis of human HCC. Overall, we have identified a new preclinical model that recapitulates known hallmarks of NASH-driven HCC that can be utilized for future molecular mechanistic studies of this disease.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Animals , Carcinoma, Hepatocellular/metabolism , Diet, Western/adverse effects , Fibrosis , Inflammation/complications , Liver Neoplasms/metabolism , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/metabolismABSTRACT
BACKGROUND AND AIMS: The mechanisms by which the I148M mutant variant of the patatin-like phospholipase domain-containing 3 (PNPLA3I148M ) drives development of nonalcoholic steatohepatitis (NASH) are not known. The aim of this study was to obtain insights on mechanisms underlying PNPLA3I148M -induced acceleration of NASH. APPROACH AND RESULTS: Hepatocyte-specific overexpression of empty vector (luciferase), human wild-type PNPLA3, or PNPLA3I148M was achieved using adeno-associated virus 8 in a diet-induced mouse model of nonalcoholic fatty liver disease followed by chow diet or high-fat Western diet with ad libitum administration of sugar in drinking water (WDSW) for 8 weeks. Under WDSW, PNPLA3I148M overexpression accelerated steatohepatitis with increased steatosis, inflammation ballooning, and fibrosis (P < 0.001 versus other groups for all). Silencing PNPLA3I148M after its initial overexpression abrogated these findings. PNPLA3I148M caused 22:6n3 docosahexanoic acid depletion and increased ceramides under WDSW in addition to increasing triglycerides and diglycerides, especially enriched with unsaturated fatty acids. It also increased oxidative stress and endoplasmic reticulum stress. Increased total ceramides was associated with signature of transducer and activator of transcription 3 (STAT3) activation with downstream activation of multiple immune-inflammatory pathways at a transcriptomic level by network analyses. Silencing PNPLA3I148M reversed STAT3 activation. Conditioned media from HepG2 cells overexpressing PNPLA3I148M increased procollagen mRNA expression in LX2 cells; this was abrogated by hepatocyte STAT3 inhibition. CONCLUSIONS: Under WDSW, PNPLA3I148M overexpression promotes steatosis and NASH by metabolic reprogramming characterized by increased triglycerides and diglycerides, n3 polyunsaturated fatty acid depletion, and increased ceramides with resultant STAT3 phosphorylation and downstream inflammatory pathway activation driving increased stellate cell fibrogenic activity.
Subject(s)
Lipase , Liver Cirrhosis , Membrane Proteins , Non-alcoholic Fatty Liver Disease , Animals , Diet, High-Fat/adverse effects , Diet, Western/adverse effects , Disease Models, Animal , Disease Progression , Gene Expression , Hep G2 Cells , Hepatic Stellate Cells/metabolism , Hepatocytes/metabolism , Humans , Lipase/genetics , Liver Cirrhosis/etiology , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Liver Cirrhosis/physiopathology , Male , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mutation , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/physiopathology , Polymorphism, Genetic , TranscriptomeABSTRACT
BACKGROUND & AIMS: Large prospective studies to establish the prevalence of non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH), are lacking. We prospectively assessed the prevalence and severity of NAFLD/NASH in a cohort of asymptomatic middle-aged Americans attending a colonoscopy class at a gastroenterology clinic. METHODS: Screening for NAFLD was performed using magnetic resonance (MR)-based LiverMultiScan® proton density fat fraction (LMS-PDFF). MR exams also included corrected T1 and elastography for liver stiffness measurement (LSM). FibroScan® was also used to measure LSM. Participants with predetermined abnormal imaging parameters were offered a liver biopsy. Biopsies were read in a blinded fashion with results based on the consensus by 2 expert pathologists. The prevalence of NAFLD was determined by PDFF ≥5% or by histological diagnosis of NAFLD (if biopsy data were available). The prevalence of NASH was defined by biopsy. RESULTS: Of 835 participants, 664 met the inclusion and exclusion criteria. The mean age was 56 ± 6.4 years, 50% were male, the mean BMI was 30.48 ± 5.46 kg/m2, and 52% were obese. The prevalence of NAFLD was 38% (95% CI 34-41%) and the prevalence of NASH was 14% (95% CI 12-17%). While no patient had cirrhosis on biopsy, significant fibrosis (F ≥2) was present in 5.9% (95% CI 4-8%) and bridging fibrosis in 1.6% (95% CI 1-3%). In a multivariable analysis, factors associated with the presence of NASH were race, obesity, and diabetes. CONCLUSION: Using state-of-the-art liver imaging modalities and reference biopsy, this study establishes an overall prevalence of NAFLD of 38% and NASH by biopsy of 14% in this cohort of asymptomatic middle-aged US adults. LAY SUMMARY: There are no prospective studies to determine how common is nonalcoholic steatohepatitis (NASH), the severe form of non-alcoholic fatty liver disease (NAFLD). In a large number of asymptomatic middle-aged Americans, we used a combination of state-of-the-art liver imaging methods and liver biopsy to prospectively determine the prevalence of NAFLD and NASH. NAFLD was diagnosed in 38%, NASH in 14%, and significant liver fibrosis in 6% of asymptomatic middle-aged Americans.
Subject(s)
Fatty Liver/diagnosis , Non-alcoholic Fatty Liver Disease/diagnosis , Cohort Studies , Fatty Liver/epidemiology , Female , Humans , Logistic Models , Magnetic Resonance Imaging/methods , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/epidemiology , Prevalence , Prospective Studies , Statistics, Nonparametric , United States/epidemiologyABSTRACT
BACKGROUND & AIMS: Histological classifications used to diagnose/stage non-alcoholic fatty liver disease (NAFLD) are based on morphology, with undetermined clinical correlates and relevance. We assessed the clinical relevance of the fatty liver inhibition of progression (FLIP) algorithm and the steatosis, activity, and fibrosis (SAF) scoring system. METHODS: One hundred and forty consecutive patients with suspected NAFLD and a separate validation cohort of 78 patients enrolled in a therapeutic trial, all with central reading of liver biopsy, were included. FLIP and SAF were used to categorize patients with non-alcoholic steatohepatitis (NASH), non-NASH NAFLD (NAFL), or non-NAFLD. The SAF activity score assessed hepatocyte ballooning and lobular inflammation; a histologically severe disease was defined as a SAF activity score of ≥3 and/or bridging fibrosis or cirrhosis. Clinical, biochemical, and metabolic data were analyzed in relation to histology. RESULTS: Patients with NASH according to the FLIP algorithm had a clinical profile distinct from those with NAFL, with a higher prevalence of metabolic risk factors (increased body mass index [BMI], central obesity, serum glucose, and glycated hemoglobin), more severe insulin resistance (fasting insulin and homeostasis model assessment for insulin resistance [HOMA-IR] values), and higher levels of aminotransferases. Similar findings were documented for patients with severe disease vs. those without. Positive linear trends existed between NASH or severe disease and increasing BMI and HOMA-IR. There was a strong association between liver fibrosis and NASH or SAF-defined scores of activity. Patients with either significant or bridging fibrosis overwhelmingly had NASH, and bridging fibrosis most often coexisted with severe activity. CONCLUSIONS: The FLIP algorithm/SAF score, although based on purely morphological grounds, are clinically relevant, as they identify patients with distinct clinical and biological profiles of disease severity. Disease activity in NAFLD is associated with fibrosis severity. LAY SUMMARY: The examination of liver tissue under the microscope (histology) serves to define the type and severity of non-alcoholic fatty liver disease morphologically, and is also used to determine improvement in therapeutic or natural history clinical trials. The FLIP algorithm/SAF classification is a new histological classification well validated on morphological but not clinical grounds. Here, we demonstrate that different disease categories defined by the FLIP/SAF classification correspond to entities of different clinical and biological severity. We also show a strong association between the activity of steatohepatitis (defined histologically) and the amount of fibrotic scar.
Subject(s)
Algorithms , Liver Cirrhosis/epidemiology , Non-alcoholic Fatty Liver Disease/classification , Non-alcoholic Fatty Liver Disease/epidemiology , Obesity, Abdominal/epidemiology , Research Design , Severity of Illness Index , Adult , Biopsy , Blood Glucose , Body Mass Index , Cohort Studies , Comorbidity , Female , Glycated Hemoglobin/metabolism , Humans , Liver/pathology , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/blood , Non-alcoholic Fatty Liver Disease/pathology , Risk FactorsABSTRACT
BACKGROUND & AIMS: Genetic factors associated with non-alcoholic fatty liver disease (NAFLD) remain incompletely understood. To date, most genome-wide association studies (GWASs) have adopted radiologically assessed hepatic triglyceride content as the reference phenotype and so cannot address steatohepatitis or fibrosis. We describe a GWAS encompassing the full spectrum of histologically characterised NAFLD. METHODS: The GWAS involved 1,483 European NAFLD cases and 17,781 genetically matched controls. A replication cohort of 559 NAFLD cases and 945 controls was genotyped to confirm signals showing genome-wide or close to genome-wide significance. RESULTS: Case-control analysis identified signals showing p values ≤5 × 10-8 at 4 locations (chromosome [chr] 2 GCKR/C2ORF16; chr4 HSD17B13; chr19 TM6SF2; chr22 PNPLA3) together with 2 other signals with p <1 × 10-7 (chr1 near LEPR and chr8 near IDO2/TC1). Case-only analysis of quantitative traits showed that the PNPLA3 signal (rs738409) had genome-wide significance for steatosis, fibrosis and NAFLD activity score and a new signal (PYGO1 rs62021874) had close to genome-wide significance for steatosis (p = 8.2 × 10-8). Subgroup case-control analysis for NASH confirmed the PNPLA3 signal. The chr1 LEPR single nucleotide polymorphism also showed genome-wide significance for this phenotype. Considering the subgroup with advanced fibrosis (≥F3), the signals on chr2, chr19 and chr22 maintained their genome-wide significance. Except for GCKR/C2ORF16, the genome-wide significance signals were replicated. CONCLUSIONS: This study confirms PNPLA3 as a risk factor for the full histological spectrum of NAFLD at genome-wide significance levels, with important contributions from TM6SF2 and HSD17B13. PYGO1 is a novel steatosis modifier, suggesting that Wnt signalling pathways may be relevant in NAFLD pathogenesis. LAY SUMMARY: Non-alcoholic fatty liver disease is a common disease where excessive fat accumulates in the liver and may result in cirrhosis. To understand who is at risk of developing this disease and suffering liver damage, we undertook a genetic study to compare the genetic profiles of people suffering from fatty liver disease with genetic profiles seen in the general population. We found that particular sequences in 4 different areas of the human genome were seen at different frequencies in the fatty liver disease cases. These sequences may help predict an individual's risk of developing advanced disease. Some genes where these sequences are located may also be good targets for future drug treatments.