CONTROL: A randomized phase 2 study of obeticholic acid and atorvastatin on lipoproteins in nonalcoholic steatohepatitis patients

The Asian Pacific Association for the Study of the Liver clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is the principal worldwide cause of liver disease and affects nearly a quarter of the global population. The objective of this work was to present the clinical practice guidelines of the Asian Pacific Association for the Study of the Liver (APASL) on MAFLD. The guidelines cover various aspects of MAFLD including its epidemiology, diagnosis, screening, assessment, and treatment. The document is intended for practical use and for setting the stage for advancing clinical practice, knowledge, and research of MAFLD in adults, with specific reference to special groups as necessary. The guidelines also seek to improve patient care and awareness of the disease and assist stakeholders in the decision-making process by providing evidence-based data. The guidelines take into consideration the burden of clinical management for the healthcare sector.

Dysregulated lipid metabolism links NAFLD to cardiovascular disease

Background

Non-alcoholic fatty liver disease (NAFLD) is rapidly becoming a global health problem. Cardiovascular diseases (CVD) are the most common cause of mortality in NAFLD patients. NAFLD and CVD share several common risk factors including obesity, insulin resistance, and type 2 diabetes (T2D). Atherogenic dyslipidemia, characterized by plasma hypertriglyceridemia, increased small dense low-density lipoprotein (LDL) particles, and decreased high-density lipoprotein cholesterol (HDL-C) levels, is often observed in NAFLD patients.

Scope of review

In this review, we highlight recent epidemiological studies evaluating the link between NAFLD and CVD risk. We further focus on recent mechanistic insights into the links between NAFLD and altered lipoprotein metabolism. We also discuss current therapeutic strategies for NAFLD and their potential impact on NAFLD-associated CVD risk.

Major conclusions

Alterations in hepatic lipid and lipoprotein metabolism are major contributing factors to the increased CVD risk in NAFLD patients, and many promising NASH therapies in development also improve dyslipidemia in clinical trials.

Combination therapy for non-alcoholic steatohepatitis: rationale, opportunities and challenges

Non-alcoholic steatohepatitis (NASH) is becoming a leading cause of cirrhosis with the burden of NASH-related complications projected to increase massively over the coming years. Several molecules with different mechanisms of action are currently in development to treat NASH, although reported efficacy to date has been limited. Given the complexity of the pathophysiology of NASH, it will take the engagement of several targets and pathways to improve the results of pharmacological intervention, which provides a rationale for combination therapies in the treatment of NASH. As the field is moving towards combination therapy, this article reviews the rationale for such combination therapies to treat NASH based on the current therapeutic landscape as well as the advantages and limitations of this approach.

Nonalcoholic Fatty Liver Disease: A Drug Revolution Is Coming

The worldwide prevalence of non-alcoholic fatty liver disease is around 25%, and that of nonalcoholic steatohepatitis (NASH) ranges from 1.5% to 6.45%. Patients with NASH, especially those with fibrosis, are at higher risk for adverse outcomes such as cirrhosis and liver-related mortality. Although vitamin E, pioglitazone, and liraglutide improved liver histology in randomized trials, there are currently no Food and Drug Administration-approved drugs for NASH. Five pharmacologic agents-obeticholic acid, elafibranor, cenicriviroc, resmetirom, and aramchol-are being evaluated in large, histology-based phase 3 trials. Within 2 to 4 years, new and effective drugs for the treatment of NASH are expected. Additionally, many phase 2 trials are ongoing for various agents. Based on the results of phase 2 and 3 trials, combination treatments are also being investigated. Future treatment strategies will comprise drug combinations and precision medicine based on the different phenotypes of NASH and treatment response of the individual patient.

Current and emerging pharmacological options for the treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent disease and important unmet medical need. Current guidelines recommend, under specific restrictions, pioglitazone or vitamin E in patients with NASH and significant fibrosis, but the use of both remains off-label. We summarize evidence on medications for the treatment of nonalcoholic steatohepatitis (NASH), since NASH has been mainly associated with higher morbidity and mortality. Some of these medications are currently in phase 3 clinical trials, including obeticholic acid (a farnesoid X receptor agonist), elafibranor (a peroxisome proliferator activated receptor [PPAR]-α/δ dual agonist), cenicriviroc (a CC chemokine receptor antagonist), MSDC-0602 K (a PPAR sparing modulator), selonsertib (an apoptosis signal-regulating kinase-1 inhibitor) and resmetirom (a thyroid hormone receptor agonist). A significant research effort is also targeting PPARs and selective PPAR modulators, including INT131 and pemafibrate, with the expectation that novel drugs may have beneficial effects similar to those of pioglitazone, but without the associated adverse effects. Whether these and other medications could offer tangible therapeutic benefits, alone or in combination, apparently on a background of lifestyle modification, i.e. exercise and a healthy dietary pattern (e.g. Mediterranean diet) remain to be proven. In conclusion, major advances are expected for the treatment of NASH.

Evolving Role for Pharmacotherapy in NAFLD/NASH

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent, dynamic disease that occurs across the age spectrum and can lead to cirrhosis and hepatocellular carcinoma. There are currently no US Food and Drug Administration (FDA) approved treatments for NAFLD; however, this is a field of active research. This review summarizes emerging pharmacotherapies for the treatment of adult and pediatric NAFLD. Investigated pharmacotherapies predominantly target bile acid signaling, insulin resistance, and lipid handling within the liver. Three drugs have gone on to phase III trials for which results are available. Of those, obeticholic acid is the single agent that demonstrates promise according to the interim analyses of the REGENERATE trial. Obeticholic acid showed reduction of fibrosis in adults with nonalcoholic steatohepatitis (NASH) taking 25 mg daily for 18 months (n = 931, reduction in fibrosis in 25% vs. 12% placebo, P < 0.01). Ongoing phase III trials include REGENERATE and MAESTRO‐NASH, which investigates thyroid hormone receptor‐β agonist MGL‐3196. Outcomes of promising phase II trials in adults with NASH are also available and those have investigated agents, including the fibroblast growth factor (FGF)19 analogue NGM282, the GLP1 agonist liraglutide, the FGF21 analogue Pegbelfermin, the sodium glucose co‐transporter 2 inhibitor Empagliflozin, the ketohexokinase inhibitor PF‐06835919, the acetyl‐coenzyme A carboxylase inhibitor GS‐0976, and the chemokine receptor antagonist Cenicriviroc. Completed and ongoing clinical trials emphasize the need for a more nuanced understanding of the phenotypes of subgroups within NAFLD that may respond to an individualized approach to pharmacotherapy.

Review article: the impact of liver-directed therapies on the atherogenic risk profile in non-alcoholic steatohepatitis

BACKGROUND

Patients with non-alcoholic fatty liver disease (NAFLD), the most common cause of chronic liver disease, are at higher risk of cardiovascular disease (CVD) and associated mortality. Therefore, it is important to understand how new therapies for non-alcoholic steatohepatitis (NASH) may impact CVD risk factors in these patients.

AIMS

To summarise the effects of drug therapies on lipid and lipoprotein levels in patients with NASH and provide insight into the potential mechanisms for the observed changes.

METHODS

PubMed searches of the literature were performed and results were compiled.

RESULTS

Recent clinical trials have highlighted the safety and efficacy of drug candidates for the treatment of NASH. Several agents have shown improvements in the histological features of NASH and liver function. Pioglitazone, a drug that is currently available for type 2 diabetes and may be useful for NASH, exhibits beneficial effects on lipids. However, agents such as farnesoid X receptor agonists, which are in development for NASH, may adversely affect circulating lipids and lipoproteins.

CONCLUSIONS

NASH is a multi-system disease with a disproportionate CVD burden. Current and future drugs for NASH have had variable impact on the atherogenic risk profile. Potential co-administration of a statin may help mitigate the negative impact of some of these therapies on lipid and lipoprotein levels.

Impact of NAFLD on the Incidence of Cardiovascular Diseases in a Primary Care Population in Germany

BACKGROUND

Patients with NAFLD are considered at a high risk of cardiovascular events due to underlying metabolic risk factors. Currently, data related to the impact of NAFLD on cardiovascular risk in the general population are lacking.

AIMS

The aim of this study was to investigate the role of NAFLD on risk of myocardial infarction (MI), coronary heart disease (CHD), atrial fibrillation (AF), and stroke in primary care in Germany.

METHODS

The study included patients diagnosed with NAFLD in primary care between 2010 and 2015. NAFLD cases (n = 22,048) were matched to a cohort without NAFLD (n = 22,048) based on age, sex, treating physician, type 2 diabetes, arterial hypertension, and hyperlipidemia. The primary outcome of the study was the incidence of MI, CHD, AF, and stroke.

RESULTS

Within 10 years of the index date, 12.8% of patients with NAFLD and 10.0% of controls were diagnosed with CHD (p < 0.001). Additionally, frequency of MI was significantly higher in NAFLD (2.9% vs. 2.3%, p < 0.001). On regression analysis, HR for incidence of MI was 1.34 (p = 0.003) in all NAFLD patients and 1.35 (p = 0.013) for men. Incidence of AF was significantly higher in patients with NAFLD. On regression analysis, HR for incidence of AF was 1.15 (p = 0.005). NAFLD was not associated with a higher incidence of stroke (HR 1.09, p = 0.243).

CONCLUSIONS

NAFLD constitutes an independent risk factor for CHD, MI, and AF in primary care in Germany. Identification of patients with NAFLD in primary care will allow specifically managing and modifying underlying risk factors to improve the overall prognosis.

Bile acid modulators for the treatment of nonalcoholic steatohepatitis (NASH)

INTRODUCTION

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) for which therapy is suboptimal. The farnesoid-X-receptor (FXR) and the G protein bile acid receptor (GPBAR)1 are two bile acid-activated receptors that exert regulatory effects on lipid, glucose, energy, and immune homeostasis. GPBAR1 and FXR ligands have shown efficacy in reversing steatohepatitis and fibrosis in preclinical models of NASH.

AREA COVERED

This article evaluates the efficacy and pitfalls of GPBAR1 and FXR-based therapies in the treatment of NASH. While there are no GPBAR1 agonist in clinical development, several FXR ligands have completed phase 2 and phase 3 trials in NASH. EDP305, tropifexor, cilofexor, nidufexor, TERN.101, Px-104, EYP001, MET409. Individual FXR agonists have shown variable efficacy in reversing liver steatohepatitis and fibrosis. Class-related, dose-dependent side effects: pruritus, increased plasma levels of cholesterol and LDLc, and reduction of HDL have been reported.

EXPERT OPINION

Efficacy of FXR agonists as stand-alone therapy is limited by dose-related side effects. Efficacy of combining an FXR agonist with statins, CCR2, and ACC inhibitors is currently investigated. Identification of patient subsets would allow development of patients tailored therapy using a combination of drugs acting on different molecular mechanisms.

Obeticholic acid for the treatment of nonalcoholic steatohepatitis

INTRODUCTION

NAFLD has grown to become the most prevalent liver disease in the world, with a quarter of the general population estimated to have the disease. NASH, characterized as NAFLD with inflammation, is associated with worsening fibrosis along with increased incidence of HCC. Despite high prevalence of this disease, no pharmacologic treatments approved by regulatory agencies are available.

AREAS COVERED

This review briefly discusses present understanding of NASH pathology and currently available treatments. We also discuss data on the role of OCA as an FXR agonist in modulating disease in NASH. A comprehensive literature search of review articles, original research articles, and prospective clinical trials from 1998 to the present was performed.

EXPERT OPINION

Based on 18-month interim findings of the REGENERATE trial, OCA likely improves fibrosis in NASH and therefore may have a beneficial effect in delaying or even preventing cirrhosis. The side effect of an atherogenic lipoprotein profile may adversely affect long-term outcomes, though studies have shown that co-administration of statins is able to mitigate this effect. OCA is likely to become an option for treatment, but the specific context within which it may be prescribed still needs to be clarified.

Toward Genetic Prediction of Nonalcoholic Fatty Liver Disease Trajectories: PNPLA3 and Beyond

Nonalcoholic fatty liver disease (NAFLD) is on the verge of becoming the leading cause of liver disease. NAFLD develops at the interface between environmental factors and inherited predisposition. Genome-wide association studies, followed by exome-wide analyses, led to identification of genetic risk variants (eg, PNPLA3, TM6SF2, and SERPINA1) and key pathways involved in fatty liver disease pathobiology. Functional studies improved our understanding of these genetic factors and the molecular mechanisms underlying the trajectories from fat accumulation to fibrosis, cirrhosis, and cancer over time. Here, we summarize key NAFLD risk genes and illustrate their interactions in a 3-dimensional "risk space." Although NAFLD genomics sometimes appears to be "lost in translation," we envision clinical utility in trial design, outcome prediction, and NAFLD surveillance.

Therapeutic Landscape for NAFLD in 2020

Lifestyle modifications focused on healthy eating and regular exercise are the primary recommendations for patients with nonalcoholic steatohepatitis (NASH). However, for multiple societal, psychological, physical, genetic, and epigenetic reasons, the ability of people to adopt and sustain such changes is challenging and typically not successful. To end the epidemic of NASH and prevent its complications, including cirrhosis and hepatocellular carcinoma, pharmacological interventions are now being evaluated in clinical trials. Treatments include drugs targeting energy intake, energy disposal, lipotoxic liver injury, and the resulting inflammation and fibrogenesis that lead to cirrhosis. It is likely that patients develop the phenotype of NASH by multiple mechanisms, and thus the optimal treatments of NASH will likely evolve to personalized therapy once we understand the mechanistic underpinnings of NASH in each patient. Reviewed here is the treatment landscape in this rapidly evolving field with an emphasis on drugs in Phase 2 and Phase 3 trials.

Current and new pharmacotherapy options for non-alcoholic steatohepatitis

INTRODUCTION

There is an unmet medical need for an effective anti-fibrotic treatment for NASH with advanced fibrosis.

AREAS COVERED

The authors review the current and novel agents for the treatment of NASH with fibrosis. They also consider the potential future strategies of combination therapies.

EXPERT OPINION

Farnesoid X receptor (FXR) agonist (obeticholic acid [OCA]) significantly ameliorated hepatic fibrosis in NASH stage 2/3 fibrosis in an interim analysis of phase 3 trial. Because OCA has several drawbacks such as itching and elevated low-density lipoprotein-cholesterol (LDL-C), non-bile acid FXR agonists are now under development. Selonsertib (apoptosis signaling kinase 1 inhibitor), emricasan (an irreversible pan-caspase inhibitor), and simtsuzumab (a monoclonal antibody against lysyl oxidase-like 2) were discontinued because of no efficacy over placebo. Peroxisome proliferator-activator receptor α/δ agonists, C-C motif chemokine receptor-2/5 antagonists, and thyroid β receptor agonist are ongoing in phase 3 trials. A variety of agents including fibroblast growth factor (FGF)-21 and FGF-19 agonists, as well as acetyl-CoA carboxylase inhibitors, are also expected. Among antidiabetic agents, semaglutide, a novel GLP-1 RA, is ongoing for NASH stage 1-3 fibrosis in a phase 2 trial. Furthermore, the combination of GLP-RA/glucagon receptor agonist and GLP-RA/gastrointestinal peptide agonist are promising future options.

Pharmacologic Treatment Strategies for Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a common form of liver disease, associated with features of the metabolic syndrome. Nonalcoholic steatohepatitis (NASH), the aggressive subtype of NAFLD, can cause progressive fibrosis leading to cirrhosis. With the obesity epidemic, there is an increased health care burden from NASH, one of the most common causes of liver transplantation in the United States. There currently are no Food and Drug Administration-approved medical therapies for NASH. There exists a need for therapeutics to correct the drivers of NASH and to reverse or halt fibrosis progression. This article reviews pharmacologic therapeutics being developed to treat NASH.

Emerging therapeutic targets for NASH: key innovations at the preclinical level

Introduction: nonalcoholic steatohepatitis (NASH) is a globally emerging health problem, mainly caused by increasing trends in the prevalence of obesity and metabolic syndrome. Patients with NASH are mainly affected by cardiovascular risk and extrahepatic cancer, but a significant proportion of patients will develop advanced liver disease, eventually resulting in liver failure or hepatocellular carcinoma. Recent research has yielded a better understanding of the underlying mechanisms and potential targetability for drug development.Areas covered: This review focuses on the role of fructose metabolism, de novo lipogenesis (DNL), endoplasmic reticulum (ER) stress, NLRP3 inflammasome, bone morphogenetic protein (BMP) signaling and platelets in the pathophysiology of NASH. We discuss the suitability of these substrates for targeting liver disease as well as cardiovascular health in patients with NASH. A non-systematic literature search was performed on PubMed and ClinicalTrials.gov.Expert opinion: Targeting fructose metabolism, DNL, ER stress, NLRP3 inflammasome, BMP signaling and platelets are promising therapeutic strategies, warranting further preclinical and clinical investigation. The discussed approaches might not only benefit liver-related outcomes but improve cardiovascular disease as well. Amidst the euphoria of advances in drug development for NASH, parallel endeavors need to address the underlying causes of obesity and metabolic syndrome to prevent NASH.

Bile Acid Receptor Therapeutics Effects on Chronic Liver Diseases

In the past ten years, our understanding of the importance of bile acids has expanded from fat absorption and glucose/lipid/energy homeostasis into potential therapeutic targets for amelioration of chronic cholestatic liver diseases. The discovery of important bile acid signaling mechanisms, as well as their role in metabolism, has increased the interest in bile acid/bile acid receptor research development. Bile acid levels and speciation are dysregulated during liver injury/damage resulting in cytotoxicity, inflammation, and fibrosis. An increasing focus to target bile acid receptors, responsible for bile acid synthesis and circulation, such as Farnesoid X receptor and apical sodium-dependent bile acid transporter to reduce bile acid synthesis have resulted in clinical trials for treatment of previously untreatable chronic liver diseases such as non-alcoholic steatohepatitis and primary sclerosing cholangitis. This review focuses on current bile acid receptor mediators and their effects on parenchymal and non-parenchymal cells. Attention will also be brought to the gut/liver axis during chronic liver damage and its treatment with bile acid receptor modulators. Overall, these studies lend evidence to the importance of bile acids and their receptors on liver disease establishment and progression.

New and emerging anti-fibrotic therapeutics entering or already in clinical trials in chronic liver diseases

Chronic liver diseases with different etiologies represent a major public health issue worldwide. Liver fibrosis is the common feature of almost all chronic liver diseases and remains a key determinant of clinical prognosis. Over the last two decades, basic science studies have uncovered molecular mechanisms underlying the pathophysiology of chronic liver diseases, leading to the recent development of new anti-fibrotic drugs. These new drugs target different steps in the pathophysiology of chronic liver injury: metabolism of glucose, lipids and bile acids, apoptosis, inflammation and fibrosis. Many targets are shared between non-alcoholic steatohepatitis (NASH) and cholestatic diseases, explaining why some drugs have been assessed concurrently in both conditions. This review reports the most recent clinical trials designed to treat liver fibrosis, with a special focus on NASH and cholestatic diseases.

Farnesoid X nuclear receptor agonists for the treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) affects 20-40% of the general population. Despite significant disease burden and mortality associated with advanced disease, i.e., nonalcoholic steatohepatitis (NASH), there is currently no approved medication for NASH. Farnesoid X receptor agonists have been investigated as candidates for the treatment of NASH. Obeticholic acid, approved for the treatment of primary biliary cholangitis, has gained significant attention after showing promising results in patients with NASH and fibrosis. Three trials investigating the effect of obeticholic acid in patients with NASH have been completed and the preliminary results of an ongoing one have also been made public. Generally, treatment with obeticholic acid improved hepatic histology, including inflammation and fibrosis, the latter being the main histological predictor of advanced disease. Nonetheless, there were adverse effects, the most common being pruritus and unfavorable changes in the lipid profile. Pruritus led to discontinuation of treatment in some patients. Obeticholic acid, however, is not the only farnesoid X receptor agonist currently investigated for the treatment of NASH. Another farnesoid X receptor agonist, cilofexor, in combination with firsocostat, an acetyl-CoA carboxylase inhibitor, improved hepatic steatosis, liver stiffness, liver function tests and serum fibrosis markers, without causing pruritus after 12 weeks of treatment. In conclusion, current evidence regarding the effect of farnesoid X receptor agonists on hepatic histology in patients with NASH is promising, but several safety issues need further evaluation.