Histological assessment based on liver biopsy: the value and challenges in NASH drug development

Clinical validation of an AI-based pathology tool for scoring of metabolic dysfunction-associated steatohepatitis

Metabolic dysfunction-associated steatohepatitis (MASH) is a major cause of liver-related morbidity and mortality, yet treatment options are limited. Manual scoring of liver biopsies, currently the gold standard for clinical trial enrollment and endpoint assessment, suffers from high reader variability. This study represents the most comprehensive multisite analytical and clinical validation of an artificial intelligence (AI)-based pathology system, AI-based measurement of metabolic dysfunction-associated steatohepatitis (AIM-MASH), to assist pathologists in MASH trial histology scoring. AIM-MASH demonstrated high repeatability and reproducibility compared to manual scoring. AIM-MASH-assisted reads by expert MASH pathologists were superior to unassisted reads in accurately assessing inflammation, ballooning, MAS ≥ 4 with ≥1 in each score category and MASH resolution, while maintaining non-inferiority in steatosis and fibrosis assessment. These findings suggest that AIM-MASH could mitigate reader variability, providing a more reliable assessment of therapeutics in MASH clinical trials.

The evolving role of liver biopsy: Current applications and future prospects

Histopathologic evaluation of liver biopsy has played a longstanding role in the diagnosis and management of liver disease. However, the utility of liver biopsy has been questioned by some, given the improved imaging modalities, increased availability of noninvasive serologic tests, and development of artificial intelligence over the past several years. In this review, we discuss the current and future role of liver biopsy in both non-neoplastic and neoplastic liver diseases in the era of improved noninvasive laboratory, radiologic, and digital technologies.

Kidney function mediates the association of per- and poly-fluoroalkyl substances (PFAS) and heavy metals with hepatic fibrosis risk

Heavy metals and per- and polyfluoroalkyl substances (PFAS) are significantly associated with the risk of hepatic fibrosis. However, the potential mediating effect of kidney function in the relationship between heavy metals, PFAS, and hepatic fibrosis risk remains unexplored. This research gap limits the development of hepatic fibrosis prevention and treatment strategies. To address this, this study conducts a cross-sectional analysis based on data from 10,870 participants in NHANES 2005-2018 to explore the relationship between heavy metals, PFAS, and the risk of hepatic fibrosis, as well as the mediating effect of kidney function. Participants with a Fibrosis-4 index <1.45 are defined as not having hepatic fibrosis in this study. Results from generalized linear regression models and weighted quantile sum regression models indicate that both individual and combined exposures to heavy metals and PFAS are positively associated with the risk of hepatic fibrosis. Nonlinear exposure-response functions suggest that there may be a threshold for the relationship between heavy metals (except mercury) and PFAS with the risk of hepatic fibrosis. Furthermore, heavy metals and PFAS increase the risk of kidney function impairment. After stratification by kidney function stage, the relationship between heavy metals (except lead) and proteinuria is not significant, while PFAS show a significant negative association with proteinuria. The decline in kidney function has a significant mediating effect in the relationship between heavy metals and PFAS and the risk of hepatic fibrosis, with mediation effect proportions all above 20%. The findings suggest that individual or combined exposure to heavy metals and PFAS does not increase the risk of hepatic fibrosis until a certain threshold is reached, and the mediating role of declining kidney function is very important. These results highlight the need to consider kidney function in the context of hepatic fibrosis risk assessment and management.

Dawn of an era of effective treatments for MAFLD

Fatty liver disease is a commonly occurring disease resulting in hepatic and extrahepatic complications. To date, there have been few available treatments beyond conventional lifestyle modification. While lifestyle modifications resulting in weight loss >10% have shown to be beneficial for metabolic dysfunction‐associated steatohepatitis (MASH), for the majority of patients, this is difficult to achieve. The recent approval of resmetirom (a thyroid hormone receptor beta agonist) by the Food and Drug Administration following positive results for histological outcomes in a phase 3 trial has opened the door for new treatments for metabolic (dysfunction)‐associated fatty liver disease (MAFLD) and MASH. There are currently a number of phase 3 trials targeting a variety of signaling pathways involved in the pathogenesis of metabolic steatohepatitis that are also promising. This review focuses on the currently available treatments for MAFLD and MASH, ongoing phase 3 clinical trials, and unresolved controversies in clinical trials in this area.

Modernizing metabolic dysfunction-associated steatotic liver disease diagnostics: the progressive shift from liver biopsy to noninvasive techniques

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing public health concern worldwide. Liver biopsy is the gold standard for diagnosing and staging MASLD, but it is invasive and carries associated risks. In recent years, there has been significant progress in developing noninvasive techniques for evaluation. This review article discusses briefly current available noninvasive assessments and the various liver biopsy techniques available for MASLD, including invasive techniques such as transjugular and transcutaneous needle biopsy, intraoperative/laparoscopic biopsy, and the evolving role of endoscopic ultrasound-guided biopsy. In addition to discussing the various biopsy techniques, we review the current state of knowledge on the histopathologic evaluation of MASLD, including the various scoring systems used to grade and stage the disease. We also explore current and alternative modalities for histopathologic evaluation, such as whole slide imaging and the utility of immunohistochemistry. Overall, this review article provides a comprehensive overview of the progress in liver biopsy techniques for MASLD and compares invasive and noninvasive modalities. However, beyond clinical trials, the practical application of liver biopsy may be limited, as ongoing advancements in noninvasive fibrosis assessments are expected to more effectively identify candidates for MASLD treatment in real-world settings.

Mixed active metabolites of the SNP-6 series of novel compounds mitigate metabolic dysfunction-associated steatohepatitis and fibrosis: promising results from pre-clinical and clinical trials

BACKGROUND

Metabolic dysfunction-associated steatohepatitis (MASH) is a growing global health concern with no effective pharmacological treatments. SNP-630, a newly developed synthetic molecule with multiple mechanisms of action, and a mixture of two of its active metabolites (SNP-630-MS) inhibit CYP2E1 expression to prevent reactive oxygen species generation, thereby reducing the accumulation of hepatic triglycerides and lowering chemokine levels. This study investigated the SNP-630's potential to alleviate the liver injury in MASH and its efficacy in both a mouse model and patients with MASH to identify a drug candidate that targets multiple pathways implicated in MASH.

METHODS

SNP-630 and SNP-630-MS were separately administered to the MASH mouse model. The tolerability, safety, and efficacy of SNP-630-MS were also evaluated in 35 patients with MASH. The primary endpoint of the study was assessment of the changes in serum alanine aminotransferase (ALT) levels from baseline to week 12, while the secondary endpoints included the evaluation of liver inflammation, steatosis, and fibrosis parameters and markers.

RESULTS

SNP-630 treatment in mice improved inflammation, liver steatosis, and fibrosis compared with that in the MASH control group. Both SNP-630 and SNP-630-MS treatments markedly reduced ALT levels, hepatic triglyceride content, and the expression of inflammatory cytokines monocyte chemoattractant protein 1 and fibrotic collagen (i.e., Col1a1, Col3a1, and Timp1) in mice. In the clinical trial, patients treated with SNP-630-MS exhibited significant improvement in ALT levels at week 12 compared with baseline levels, with no reports of severe adverse events. This improvement in ALT levels surpassed that achieved with most other MASH candidates. SNP-630-MS demonstrated potential antifibrotic effects, as evidenced by a significant decrease in the levels of fibrogenesis-related biomarkers such as CCL4, CCL5, and caspase 3. Subgroup analysis using FibroScan measurements further indicated the efficacy of SNP-630-MS in ameliorating liver fibrosis.

CONCLUSIONS

SNP-630 and SNP-630-MS demonstrated favorable results in mice. SNP-630-MS showed excellent tolerability in mice and patients with MASH. Efficacy analyses indicated that SNP-630-MS improved liver steatosis and injury in patients with MASH, suggesting that SNP-630 and 630-MS are promising therapeutic options for MASH. Larger scale clinical trials remain warranted to assess the efficacy and safety of SNP-630 in MASH.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03868566. Registered 06 March 2019-Retrospectively registered, https://clinicaltrials.gov/study/NCT03868566.

Biomarkers for Health Functional Foods in Metabolic Dysfunction-Associated Steatotic Liver Disorder (MASLD) Prevention: An Integrative Analysis of Network Pharmacology, Gut Microbiota, and Multi-Omics

Metabolic dysfunction-associated steatotic liver disorder (MASLD) is increasingly prevalent globally, highlighting the need for preventive strategies and early interventions. This comprehensive review explores the potential of health functional foods (HFFs) to maintain healthy liver function and prevent MASLD through an integrative analysis of network pharmacology, gut microbiota, and multi-omics approaches. We first examined the biomarkers associated with MASLD, emphasizing the complex interplay of genetic, environmental, and lifestyle factors. We then applied network pharmacology to identify food components with potential beneficial effects on liver health and metabolic function, elucidating their action mechanisms. This review identifies and evaluates strategies for halting or reversing the development of steatotic liver disease in the early stages, as well as biomarkers that can evaluate the success or failure of such strategies. The crucial role of the gut microbiota and its metabolites for MASLD prevention and metabolic homeostasis is discussed. We also cover state-of-the-art omics approaches, including transcriptomics, metabolomics, and integrated multi-omics analyses, in research on preventing MASLD. These advanced technologies provide deeper insights into physiological mechanisms and potential biomarkers for HFF development. The review concludes by proposing an integrated approach for developing HFFs targeting MASLD prevention, considering the Korean regulatory framework. We outline future research directions that bridge the gap between basic science and practical applications in health functional food development. This narrative review provides a foundation for researchers and food industry professionals interested in developing HFFs to support liver health. Emphasis is placed on maintaining metabolic balance and focusing on prevention and early-stage intervention strategies.

SomaLogic proteomics reveals new biomarkers and provides mechanistic, clinical insights into Acetyl coA Carboxylase (ACC) inhibition in Non-alcoholic Steatohepatitis (NASH)

Non-alcoholic Fatty Liver Disease (NAFLD) and Non-alcoholic Steatohepatitis (NASH) are major metabolic diseases with increasing global prevalence and no approved therapies. There is a mounting need to develop biomarkers of diagnosis, prognosis and treatment response that can effectively replace current requirements for liver biopsies, which are invasive, error-prone and expensive. We performed SomaLogic serum proteome profiling with baseline (n = 231) and on-treatment (n = 72, Weeks 12 and 16, Placebo and 25 mg PF-05221304) samples from a Phase 2a trial (NCT03248882) with Clesacostat (PF-05221304), an acetyl coA carboxylase inhibitor (ACCi) in patients with NAFLD/NASH. SomaSignal NASH probability scores and expression data for 7000+ analytes were analyzed to identify potential biomarkers associated with baseline clinical measures of NAFLD/NASH [Magnetic Resonance Imaging-Proton Density Fat Fraction (MRI-PDFF), alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] as well as biomarkers of treatment response to ACCi. SomaSignal NASH probability scores identified biopsy-proven/clinically defined NIT-based (Presumed) NASH classification of the cohort with > 70% agreement. Clesacostat-induced reduction in steatosis probability scores aligned with observed clinical reduction in hepatic steatosis based on MRI-PDFF. We identify a set of 69 analytes that robustly correlate with clinical measures of hepatic inflammation and steatosis (MRI-PDFF, ALT and AST), 27 of which were significantly reversed with ACC inhibition. Clesacostat treatment dramatically upregulated Wnt5a protein and Apolipoproteins C3 and E, with drug-induced changes significantly correlating to changes on MRI-PDFF. Our data demonstrate the utility of SomaLogic- analyte panel for diagnosis and treatment response in NAFLD/NASH and provide potential new mechanistic insights into liver steatosis reduction, inflammation and serum triglyceride elevation with ACC inhibition. (Clinical Trial Identifier: NCT03248882).

FibroScan-aspartate transaminase: A superior non-invasive model for diagnosing high-risk metabolic dysfunction-associated steatohepatitis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) with hepatic histological NAFLD activity score ≥ 4 and fibrosis stage F ≥ 2 is regarded as "at risk" non-alcoholic steatohepatitis (NASH). Based on an international consensus, NAFLD and NASH were renamed as metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH), respectively; hence, we introduced the term "high-risk MASH". Diagnostic values of seven non-invasive models, including FibroScan-aspartate transaminase (FAST), fibrosis-4 (FIB-4), aspartate transaminase to platelet ratio index (APRI), etc. for high-risk MASH have rarely been studied and compared in MASLD.

AIM

To assess the clinical value of seven non-invasive models as alternatives to liver biopsy for diagnosing high-risk MASH.

METHODS

A retrospective analysis was conducted on 309 patients diagnosed with NAFLD via liver biopsy at Beijing Ditan Hospital, between January 2012 and December 2020. After screening for MASLD and the exclusion criteria, 279 patients were included and categorized into high-risk and non-high-risk MASH groups. Utilizing threshold values of each model, sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV), were calculated. Receiver operating characteristic curves were constructed to evaluate their diagnostic efficacy based on the area under the curve (AUROC).

RESULTS

MASLD diagnostic criteria were met by 99.4% patients with NAFLD. The MASLD population was analyzed in two cohorts: Overall population (279 patients) and the subgroup (117 patients) who underwent liver transient elastography (FibroScan). In the overall population, FIB-4 showed better diagnostic efficacy and higher PPV, with sensitivity, specificity, PPV, NPV, and AUROC of 26.9%, 95.2%, 73.5%, 72.2%, and 0.75. APRI, Forns index, and aspartate transaminase to alanine transaminase ratio (ARR) showed moderate diagnostic efficacy, whereas S index and gamma-glutamyl transpeptidase to platelet ratio (GPR) were relatively weaker. In the subgroup, FAST had the highest diagnostic efficacy, its sensitivity, specificity, PPV, NPV, and AUROC were 44.2%, 92.3%, 82.1%, 67.4%, and 0.82. The FIB-4 AUROC was 0.76. S index and GPR exhibited almost no diagnostic value for high-risk MASH.

CONCLUSION

FAST and FIB-4 could replace liver biopsy as more effectively diagnostic methods for high-risk MASH compared to APRI, Forns index, ARR, S index, and GPR; FAST is superior to FIB-4.

A Machine Learning Method to Identify the Risk Factors for Liver Fibrosis Progression in Nonalcoholic Steatohepatitis

AIM

Nonalcoholic fatty liver disease (NAFLD) is a silent epidemy that has become the most common chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH) is an advanced stage of NAFLD, which is linked to a high risk of cirrhosis and hepatocellular carcinoma. The aim of this study is to develop a predictive model to identify the main risk factors associated with the progression of hepatic fibrosis in patients with NASH.

METHODS

A database from a multicenter retrospective cross-sectional study was analyzed. A total of 215 patients with NASH biopsy-proven diagnosed were collected. NAFLD Activity Score and Kleiner scoring system were used to diagnose and staging these patients. Noninvasive tests (NITs) scores were added to identify which one were more reliable for follow-up and to avoid biopsy. For analysis, different Machine Learning methods were implemented, being the eXtreme Gradient Booster (XGB) system the proposed algorithm to develop the predictive model.

RESULTS

The most important variable in this predictive model was High-density lipoprotein (HDL) cholesterol, followed by systemic arterial hypertension and triglycerides (TG). NAFLD Fibrosis Score (NFS) was the most reliable NIT. As for the proposed method, XGB obtained higher results than the second method, K-Nearest Neighbors, in terms of accuracy (95.05 vs. 90.42) and Area Under the Curve (0.95 vs. 0.91).

CONCLUSIONS

HDL cholesterol, systemic arterial hypertension, and TG were the most important risk factors for liver fibrosis progression in NASH patients. NFS is recommended for monitoring and decision making.

High-risk population of progressive hepatic fibrosis in chronic hepatitis B patients on antiviral therapy

BACKGROUND

Progressive hepatic fibrosis leads to hepatocellular carcinoma (HCC) and decompensated cirrhosis. The aim of this study was to identify the high-risk population for progressive hepatic fibrosis and the incidence of HCC and decompensated cirrhosis in chronic hepatitis B (CHB) patients with antiviral therapy.

METHODS

The data came from a multicenter, center-randomized, double-blind clinical trial that analyzed only patients in the ETV-treated arm. There was 156 hepatitis B e antigen (HBeAg)-positive and 135 HBeAg-negative patients in 14 institutions. The primary endpoint was fibrosis reversal on 72-week Entecavir (ETV) treatment. The 7-year cumulative incidence of HCC and decompensated cirrhosis were analyzed. Multivariate logistic and LASSO regression analyses were used to screen variables associated with fibrosis reversal.

RESULTS

86/156 (55%) HBeAg-positive and 58/135 (43%) HBeAg-negative patients achieved fibrosis reversal on 72-week ETV treatment. Average age was 43 years, 203 (69.8%) was male, and 144 (49.5%) patients had cirrhosis. Age ≥ 40 years (OR: 0.46, 95% CI 0.23-0.93) and HBcrAg ≥ 8.23 log U/ml (OR: 2.72, 95% CI 1.33-5.54) in HBeAg-positive patients and HBV genotype C (OR: 0.44, 95% CI 0.21-0.97) in HBeAg-negative patients were independent factors of fibrosis reversal. It was confirmed in patients with cirrhosis. After 7-year ETV treatment, seven (4.5%) HBeAg-positive patients occurred HCC or decompensated cirrhosis, including four patients with age ≥ 40 years and six with HBcrAg 8.23log U/ml, while twelve (8.9%) HBeAg-negative patients occurred, including eleven with HBV genotype C.

CONCLUSIONS

HBeAg-positive patients with a low HBcrAg level or old age, and HBeAg-negative patients with HBV genotype C tended to develop progressive hepatic fibrosis and had a high incidence of HCC and decompensated cirrhosis, even on ETV treatment.

Raman imaging of rat nonalcoholic fatty liver tissues reveals distinct biomolecular states

An essential challenge in diagnosing states of nonalcoholic fatty liver disease (NAFLD) is the early prediction of progression from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) before the disease progresses. Histological diagnoses of NAFLD rely on the appearance of anomalous tissue morphologies, and it is difficult to segment the biomolecular environment of the tissue through a conventional histopathological approach. Here, we show that hyperspectral Raman imaging provides diagnostic information on NAFLD in rats, as spectral changes among disease states can be detected before histological characteristics emerge. Our results demonstrate that Raman imaging of NAFLD can be a useful tool for histopathologists, offering biomolecular distinctions among tissue states that cannot be observed through standard histopathological means.

Advancements in MAFLD Modeling with Human Cell and Organoid Models

Metabolic (dysfunction) associated fatty liver disease (MAFLD) is one of the most prevalent liver diseases and has no approved therapeutics. The high failure rates witnessed in late-phase MAFLD drug trials reflect the complexity of the disease, and how the disease develops and progresses remains to be fully understood. In vitro, human disease models play a pivotal role in mechanistic studies to unravel novel disease drivers and in drug testing studies to evaluate human-specific responses. This review focuses on MAFLD disease modeling using human cell and organoid models. The spectrum of patient-derived primary cells and immortalized cell lines employed to model various liver parenchymal and non-parenchymal cell types essential for MAFLD development and progression is discussed. Diverse forms of cell culture platforms utilized to recapitulate tissue-level pathophysiology in different stages of the disease are also reviewed.

Developing a New qFIBS Model Assessing Histological Features in Pediatric Patients With Non-alcoholic Steatohepatitis

Background

The evolution of pediatric non-alcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH) is associated with unique histological features. Pathological evaluation of liver specimen is often hindered by observer variability and diagnostic consensus is not always attainable. We investigated whether the qFIBS technique derived from adult NASH could be applied to pediatric NASH.

Materials and Methods

102 pediatric patients (<18 years old) with liver biopsy-proven NASH were included. The liver biopsies were serially sectioned for hematoxylin-eosin and Masson trichrome staining for histological scoring, and for second harmonic generation (SHG) imaging. qFIBS-automated measure of fibrosis, inflammation, hepatocyte ballooning, and steatosis was estabilshed by using the NASH CRN scoring system as the reference standard.

Results

qFIBS showed the best correlation with steatosis (r = 0.84, P < 0.001); with ability to distinguish different grades of steatosis (AUROCs 0.90 and 0.98, sensitivity 0.71 and 0.93, and specificity 0.90 and 0.90). qFIBS correlation with fibrosis (r = 0.72, P < 0.001) was good with high AUROC values [qFibrosis (AUC) > 0.85 (0.85–0.95)] and ability to distinguish different stages of fibrosis. qFIBS showed weak correlation with ballooning (r = 0.38, P = 0.028) and inflammation (r = 0.46, P = 0.005); however, it could distinguish different grades of ballooning (AUROCs 0.73, sensitivity 0.36, and specificity 0.92) and inflammation (AUROCs 0.77, sensitivity 0.83, and specificity 0.53).

Conclusion

It was demonstrated that when qFIBS derived from adult NASH was performed on pediatric NASH, it could best distinguish the various histological grades of steatosis and fibrosis.