Proof-of-concept study to evaluate the safety and efficacy of saroglitazar in patients with primary biliary cholangitis.

BACKGROUND & AIM: Saroglitazar is a novel peroxisome proliferator-activated receptor (PPAR) agonist with dual agonistic properties (α/γ). Due to a strong mechanistic rationale, we aimed to test the safety and efficacy of saroglitazar in patients with primary biliary cholangitis (PBC) who were either ursodeoxycholic acid (UDCA) resistant or intolerant. METHODS: In this double-blind, phase II proof-of-concept trial, 37 patients with PBC were randomized to saroglitazar 4 mg (n = 13), saroglitazar 2 mg (n = 14), or placebo (n = 10) daily for 16 weeks. The primary efficacy endpoint was the reduction in alkaline phosphatase (ALP) level at Week 16. RESULTS: A significant reduction of mean ALP levels was observed at Week 16 relative to baseline in both the saroglitazar 4 mg (least-squares [LS] mean =-163.3 U/L, SE = 25.1, p <0.001) and 2 mg (LS mean =-155.8 U/L, SE = 24.4, p <0.001) groups, compared with placebo (LS mean =-21.1 U/L, SE = 28.9). Treatment with saroglitazar resulted in a rapid reduction of ALP concentration at Week 4 that was sustained through the study duration. At least 1 treatment-emergent adverse event occurred in 11 (84.6%) patients in the saroglitazar 4 mg group, in 12 (85.7%) patients in the 2 mg group and in 8 (80%) patients in the placebo group. Study drug was discontinued in 4 patients (3 patients in the 4 mg group and 1 patient in the 2 mg group) due to aminotransferase increases that promptly returned to baseline values after drug discontinuation. CONCLUSIONS: Saroglitazar at 2 mg and 4 mg daily was tolerated and resulted in rapid and sustained improvements in ALP. Further studies are underway at a daily dose of 2 mg and 1 mg due to the higher incidence of elevated liver enzymes observed with the 4 mg dose. CLINICALTRIALS. GOV IDENTIFIER: NCT03112681 LAY SUMMARY: Saroglitazar resulted in a rapid and sustained improvement in alkaline phosphatase levels in patients with primary biliary cholangitis. The mean percentage reductions in alkaline phosphatase levels were 49% and 51% in the saroglitazar 4 mg and 2 mg groups compared to 3% in the placebo group.

Cyr61 Alleviates Cholangitis by Inhibiting Cytotoxic Effects of CD8+ T Cells on Biliary Epithelial Cells.

OBJECTIVE: Primary biliary cholangitis (PBC) is a chronic progressive cholestatic liver disease. In recent years, researchers have found that cysteine-rich angiogenic inducer 61 (Cyr61, also known as CCN1) has a potential role in reducing portal inflammation in patients with PBC. This study aimed to explore the relationship between Cyr61 and PBC to provide new ideas and an experimental basis for the clinical treatment of PBC. METHODS: After induction of the overexpression of Cyr61 in a mouse model of PBC using recombinant adenovirus, hematoxylin and eosin staining and pathological scores were used to indicate intrahepatic inflammation and bile duct damage. Real-time PCR was used to detect changes in inflammation-related cytokines in the liver. To further study the mechanism, we assessed whether Cyr61 protects bile duct epithelial cells from cytotoxic effects. RESULTS: Serum and hepatic Cyr61 levels were increased in the murine model of PBC. Overexpression of Cyr61 alleviated hepatic inflammation and bile duct injury in vivo. Cyr61 inhibited the cytotoxic effects of CD8+ T cells by acting on biliary epithelial cells (BECs) in vitro. CONCLUSION: Our results provide novel insight into the pathogenesis of PBC and suggest that Cyr61 plays a dominant role in the cytotoxic effects on BECs in PBC. Consequently, therapeutic strategies targeting Cyr61 could be a potent therapy for PBC.

Alterations in microbiota and their metabolites are associated with beneficial effects of bile acid sequestrant on icteric primary biliary Cholangitis.

Background: Increasing data suggests an interaction between bile acids and intestinal microbiota in the pathogenesis of primary biliary cholangitis (PBC). Bile acid sequestrants are widely used to bind bile acids in the intestinal lumen and are therefore posited to impact gut bacteria. Herein we aimed to investigate the effects of cholestyramine on the bile acid profile and gut microbiome in a cohort of icteric PBC patients.Results: Thirty-three PBC patients were treated with cholestyramine, serum and stool samples were collected at baseline, 4 and 16 weeks. Shotgun metagenomic sequencing and targeted metabolomic profiling were performed. Following cholestyramine administration, patients exhibited a high interpersonal variability in remission of cholestasis, and were therefore dichotomized according to the decrease of total bilirubin. Gut microbial co-abundance networks showed distinct taxa interactions between subjects with superior remission (SR) and those with inferior remission (IR) at baseline. After treatment, compositional shifts of the microbiome in the SR group were characterized with enrichment of two Lachnospiraceae species, typically producing short-chain fatty acids (SCFAs). In contrast, Klebsiella pneumonia, a commensal pathobiont, was only increased in the IR group. Correspondingly, metabolome analysis demonstrated that patients with SR, but not IR, were marked by elevations of SCFAs including valeric acid and caproic acid. Finally, integrative analysis identified robust associations between the variations of microbiota, metabolites, and inflammatory cytokines in SR group, indicating potential mechanistic links.Conclusions: Beneficial responses caused by cholestyramine were closely related with compositional and functional alterations in gut commensal, highlighting the possibility of exploring bile acid-microbiota interactions for treating PBC.

Cholestatic Liver Disease: Current Treatment Strategies and New Therapeutic Agents.

Cholestatic liver disease is a disease that causes liver damage and fibrosis owing to bile stasis. It is represented by primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), but the pathophysiological pathways that cause bile stasis in both diseases are different. The pathogenesis of the disease is still unclear, although autoimmune mechanisms have been postulated and partially elucidated. Although the disease may progress slowly with only mild liver dysfunction, it may progress to liver cirrhosis or liver failure, which require liver transplantation. As a medical treatment, ursodeoxycholic acid is widely used for PBC and has proved to be very effective against disease progression in cases of PBC. On the other hand, its efficacy is limited in cases of PSC, and the research and development of various drugs are underway. Furthermore, the clinical course of both diseases is quite variable, making the design of clinical trials fairly difficult. In this review, we present the general natural history of PBC and PSC, and provide information on the latest drug therapies currently available and those that are under investigation.

Roles of Cl­/HCO3­ anion exchanger 2 in the physiology and pathophysiology of the digestive system (Review).

Cl­/HCO3­ anion exchangers (AEs), which are members of the solute carrier 4 family, contribute to the exchange of one intracellular HCO3­ for one extracellular Cl­. AE2, a vital subtype of the Cl­/HCO3­ exchangers, is expressed widely in various cells and tissues in mammals and serves essential roles in the pathophysiological processes of the cardiovascular system and renal tubular reabsorption. Recently, research on the function of AE2 in the digestive system shed new light on its roles in the regulation of cellular and organ physiology. AE2 not only participates in gastric acid secretion, but also mediates bile secretion and digestive cancer development. The aim of the present review was to describe the role of AE2 in the physiology and pathophysiology of the digestive system, with the aim of guiding clinical diagnosis and treatment.

Managing cognitive symptoms and fatigue in cholestatic liver disease.

Introduction: Patients with cholestatic diseases may develop fatigue and cognitive symptoms. The impact of symptom burden may be significant in some patients. To date, there are no effective pharmacological therapies to improve cognitive symptoms or fatigue in cholestasis and we are wholly reliant on supportive approaches. Area covered: This review provides an overview of cognitive symptoms and fatigue in the cholestatic liver disease primary biliary cholangitis (PBC), including pathophysiology and our approach to the management of these symptoms. Expert opinion: The impact of fatigue and cognitive symptoms on the perceived quality of life can be profound for patients with PBC. The pathophysiology of these symptoms is complex and poorly understood, making the development of therapeutic trials of symptom-directed therapies challenging. The current recommended management for fatigue and cognitive symptoms is mainly supportive.

Review article: pathophysiology and management of primary biliary cholangitis.

BACKGROUND: Primary biliary cholangitis (PBC), an immune-mediated disease characterised by destruction of intrahepatic bile ducts, results in progressive damage to the biliary tree, cholestasis and ultimately advanced liver disease. In the last decade, advances in practice have improved clinical care, driven novel therapeutic options and improved risk stratification tools. AIMS: To provide an overview of the disease characteristics of PBC and review a patient-centred management approach for the clinical team caring for those with PBC. METHODS: We reviewed the current literature and guidelines on PBC with a focus on management and therapies. RESULTS: A confident diagnosis of PBC is usually made based on serum liver tests and immune serology. Management of PBC should focus on three main 'process' pillars: (a) treat and risk-stratify through use of biochemical and prognostic criteria; (b) manage concurrent symptoms and other associated diseases; and (c) stage disease, monitor progression and prevent complications. With ongoing complexities in management, including a newly licensed therapy (obeticholic acid) and alternative non-licensed treatments and ongoing clinical trials, discussion with PBC expert centres is encouraged. CONCLUSIONS: PBC is a dynamic disease wherein current treatment goals have become appropriately ambitious. Goals of care should prioritise prevention of end-stage liver disease and amelioration of patient symptom burden for all.

Dysregulation of Circulating FGF19 and Bile Acids in Primary Biliary Cholangitis-Autoimmune Hepatitis Overlap Syndrome.

BACKGROUND: Primary biliary cholangitis-autoimmune hepatitis overlap syndrome (PBC-AIH OS), which exhibits features between autoimmune hepatitis and cholestasis, is a common condition and usually shows a progressive course toward cirrhosis and liver failure without adequate treatment. Synthesis of bile acids (BAs) plays an important role in liver injury in cholestasis, and the process is regulated by fibroblast growth factor 19 (FGF19). The overall role of circulating FGF19 in BA synthesis and PBC-AIH OS requires further investigation. METHODS: We analyzed BA synthesis and correlated clinical parameters with serum BAs and FGF19 in 35 patients with PBC-AIH OS. Serum concentrations of 7alpha-hydroxycholest-4-en-3-one (C4) were used to quantify the synthesis of BA directly. RESULTS: Serum FGF19 levels were higher, while C4 levels were substantially lower in PBC-AIH OS patients than those in healthy controls. Circulating FGF19 levels strongly correlated with C4 (r = -0.695, p < 0.0001), direct bilirubin (r = 0.598, p = 0.0001), and total bile acids (r = 0.595, p = 0.002). Moreover, circulating FGF19 levels strongly correlated with the model for end-stage liver disease score (r = 0.574, p = 0.0005) and Mayo risk score (r = 0.578, p = 0.001). CONCLUSIONS: Serum FGF19 is significantly increased in patients with PBC-AIH OS, while BA synthesis is suppressed. Circulating FGF19 primarily controls the regulation of BA synthesis in response to cholestasis and under cholestatic conditions. Therefore, modulation of circulating FGF19 could provide a promising targeted therapy for patients with PBC-AIH OS.

Kupffer Cells Regulate Natural Killer Cells Via the NK group 2, Member D (NKG2D)/Retinoic Acid Early Inducible-1 (RAE-1) Interaction and Cytokines in a Primary Biliary Cholangitis Mouse Model.

BACKGROUND Kupffer cells and natural killer (NK) cells has been identified as contributing factors in the pathogenesis of hepatitis, but the detailed mechanism of these cell types in the pathogenesis of primary biliary cholangitis (PBC) is poorly understood. MATERIAL AND METHODS In this study, polyinosinic: polycytidylic acid (poly I: C), 2-octynoic acid-bovine serum albumin (2OA-BSA) and Freund's adjuvant (FA) were injected to establish a murine PBC model, from which NK cells and Kupffer cells were extracted and isolated. The cells were then co-cultivated in a designed culture system, and then NK group 2, member D (NKG2D), retinoic acid early inducible-1 (RAE-1), F4/80, and cytokine expression levels were detected. RESULTS The results showed close crosstalk between Kupffer cells and NK cells. PBC mice showed increased surface RAE-1 protein expression and Kupffer cell cytokine secretion, which subsequently activated NK cell-mediated target cell killing via NKG2D/RAE-1 recognition, and increased inflammation. NK cell-derived interferon-γ (IFN-γ) and Kupffer cell-derived tumor necrosis factor alpha (TNF-alpha) were found to synergistically regulate inflammation. Moreover, interleukin (IL)-12 and IL-10 improved the crosstalk between NK cells and Kupffer cells. CONCLUSIONS Our findings in mice are the first to suggest the involvement of the NKG2D/RAE-1 interaction and cytokines in the synergistic effects of NK and Kupffer cells in PBC.

Epidemiology and clinical course of primary biliary cholangitis in Eastern Slovakia.

OBJECTIVE: To determine both the incidence and the prevalence of primary biliary cholangitis (PBC) in Eastern Slovakia and to describe its clinical course and the response to ursodeoxycholic acid (UDCA). METHODS: We recorded data of patients with PBC, who were followed up in gastroenterology and hepatology centers in Eastern Slovakia during the period from June 30, 1999, through June 30, 2019. RESULTS: The annual incidence of PBC varied from 0.7 to 1.5 cases per 100,000 inhabitants between 2014 and 2018. PBC prevalence steadily increased from initial 10.2 cases per 100,000 inhabitants in 2014 to 14.9 cases per 100,000 inhabitants in June 2019. The mean age at the time of diagnosis was 56.3 ± 10.9 years. 95.7% of patients were females, and female/male gender ratio was 22.3:1. In June 2019, prevalence in the female population was 28 cases per 100,000 women. At the time of diagnosis, three-quarters of patients were symptomatic and 10% of patients had liver cirrhosis. The mean follow-up was 7.3 ± 5.2 years. Response to UDCA was observed in 72.1% of patients. Patients with higher baseline alkaline phosphatase (ALP) levels, liver cirrhosis at entry or at the end of follow-up and women younger than 45 years responded worse to UDCA. One-quarter of patients had liver cirrhosis at the end of follow-up. During follow-up, 1.6% of patients underwent liver transplantation and 5.5% of patients died. Five-year and 10-year liver-related mortalities were 2.7% and 4.3%, respectively. CONCLUSION: PBC prevalence in Eastern Slovakia is increasing, and most of the patients respond to therapy with UDCA.

Emerging drugs for the treatment of primary biliary cholangitis.

INTRODUCTION: Primary biliary cholangitis (PBC) is a progressive inflammatory autoimmune cholestatic liver disease. Without treatment, it may result in fibrosis and eventually end stage liver disease. In addition to the disease burden, the symptom impact on the quality of life for PBC patients is significant. Ursodeoxycholic acid, and the second-line therapy, Obeticholic acid, are the only available licensed treatments. Although there has been rapid development of novel therapies in recent years for the treatment of PBC, there are very few symptoms directed therapies. AREA COVERED: This literature review aims to review the current treatment landscape in PBC and to explore how the next few years may unfold in the field. The current guidelines and emerging therapies in phase 2, 3 and 4 clinical trials have been included. EXPERT OPINION: The currently available therapies are effective, but their use has limitations and challenges and there is still significant unmet need. Although there have been promising therapeutic interventions in recent years, further research into personalizing therapeutic strategies with available treatments and new agents is needed.

Emerging therapies for PBC.

Primary biliary cholangitis is an uncommon cholestatic liver disease predominantly affecting middle-aged women. Left untreated, there is a high risk of progression to end-stage liver disease. Few treatment options exist. To date, ursodeoxycholic acid (UDCA) and obeticholic acid (OCA) are the only medical therapies approved for use, other than symptomatic treatments and liver transplantation, the latter of which is reserved for those developing complications of cirrhosis or with intractable pruritus. UDCA improves outcomes, but many patients do not adequately respond. OCA therapy may improve response, but long-term data are limited. New therapies are desperately needed, but evaluation has been limited by the fact that the disease is heterogeneous, hard end points take years to develop, and there are different criteria in use for determining therapeutic response based on surrogate biomarkers. Fibrates appear to be the most promising new therapy and have beneficially affected surrogate end points and are beginning to show improvement in clinical end points.

The Pharmacologic Management of Osteoporosis in Primary Biliary Cholangitis: A Systematic Review and Meta-Analysis.

INTRODUCTION: Osteoporosis is a common complication of primary biliary cholangitis (PBC) yet evidence for effective therapy is lacking. We sought to review all randomized controlled trials evaluating pharmacotherapy against placebo or no intervention for treatment of osteoporosis in PBC. METHODOLOGY: A comprehensive database search was conducted from inception through 29 March 2017. The primary outcome was incidence of fractures; secondary outcomes were change in bone mineral density (BMD) and adverse events. We assessed studies for risk of bias, graded quality of evidence, and used meta-analysis to obtain overall effect by pooling studies of the same drug class. RESULTS: We identified 11 randomized controlled trials evaluating bisphosphonates (3), hormone replacement therapy (2), ursodeoxycholic acid (1), obeticholic acid (1), cyclosporin A (1), vitamin K (1), calcitriol (1), and sodium fluoride (1). No intervention significantly reduced fractures compared to control. Although significant improvement in BMD was seen in one study with alendronate, a third-generation bisphosphonate, no significant improvement was seen on pooled analysis of all bisphosphonates including first-generation bisphosphonates (standard mean difference 0.41, p = 0.68). On pooled analysis, hormone replacement therapy modestly improved lumbar BMD (standard mean difference 0.69, p = 0.02), but with significantly increased adverse events (odds ratio 8.82, p = 0.01). CONCLUSIONS: There is a lack of high-quality evidence supporting the efficacy of any treatment of osteoporosis in PBC. This may be explained by lack of power in the included studies. However, our current understanding of PBC-related osteoporosis indicates that it results from decreased bone formation, which may explain the attenuated effect of traditional antiresorptive agents. Future studies should investigate newer anabolic bone agents.

Drug Therapies for Chronic Cholestatic Liver Diseases.

Though ursodeoxycholic acid (UDCA) remains the baseline treatment for most cholestatic liver diseases, UDCA treatment leaves approximately one-third of patients with primary biliary cholangitis (PBC) and all patients with primary sclerosing cholangitis (PSC) at risk for disease progression. New anticholestatic agents, including nuclear receptor agonists, choleretics, and bile acid synthesis suppressors, will likely increase response rates to therapy in PBC and PSC. Strategies that target early immune-mediated injury have so far been disappointing, hampered by the lack of biomarkers to detect early disease states, which then could profit from immunomodulatory therapy. Future concepts need to personalize treatments according to disease stage, progression, and phase, and to combine multiple drugs to target different pathogenic pathways.

Current and potential treatments for primary biliary cholangitis.

Up to 40% of patients with primary biliary cholangitis have an incomplete response to first-line treatment with ursodeoxycholic acid. Obeticholic acid was approved by the US Food and Drug Administration in 2016 as a second-line treatment for patients with primary biliary cholangitis who are unresponsive to ursodeoxycholic acid; however, approximately 50% of patients might need additional treatments to reach therapeutic goals. A considerable need exists for effective treatment options to prevent progression to liver transplantation or death in these patients. Drugs that might modulate immunological abnormalities in primary biliary cholangitis have been studied but their effectiveness varies. Budesonide, ciclosporin, and rituximab have shown potential in modifying the disease process. Bezafibrate, a pan-peroxisome proliferator-activated receptor agonist, has been shown to ameliorate deranged bile acid homoeostasis and attenuate raised concentrations of liver enzymes associated with primary biliary cholangitis. As the mechanisms underlying the pathogenesis and progression of primary biliary cholangitis are further clarified, specific targeted therapies are under development with promising early results. Various therapeutic target bile acid homeostasis, immune dysfunction, and fibrogenetic pathways are being studied. A better understanding of the biochemical and clinical effects of the therapies in development bear discussion, both to guide the discovery of new therapies and to inform clinicians so that rational treatment regimens can be tailored to patients once they become available.

Emperipolesis mediated by CD8+ T cells correlates with biliary epithelia cell injury in primary biliary cholangitis.

Primary biliary cholangitis (PBC) is an autoimmune disease characterized by chronic destruction of the bile ducts. A major unanswered question regarding the pathogenesis of PBC is the precise mechanisms of small bile duct injury. Emperipolesis is one of cell-in-cell structures that is a potential histological hallmark associated with chronic hepatitis B. This study aimed to clarify the pathogenesis and characteristics of emperipolesis in PBC liver injury. Sixty-six PBC patients, diagnosed by liver biopsy combined with laboratory test, were divided into early-stage PBC (stages I and II, n = 39) and late-stage PBC (stages III and IV, n = 27). Emperipolesis was measured in liver sections stained with haematoxylin-eosin. The expressions of CK19, CD3, CD4, CD8, CD20, Ki67 and apoptosis of BECs were evaluated by immunohistochemistry or immunofluorescence double labelling. Emperipolesis was observed in 62.1% of patients with PBC, and BECs were predominantly host cells. The number of infiltrating CD3+ and CD8+ T cells correlated with the advancement of emperipolesis (R2  = 0.318, P < .001; R2  = 0.060, P < .05). The cell numbers of TUNEL-positive BECs and double staining for CK19 and Ki67 showed a significant positive correlation with emperipolesis degree (R2  = 0.236, P < .001; R2  = 0.267, P < .001). We conclude that emperipolesis mediated by CD8+ T cells appears to be relevant to apoptosis of BEC and thus may aggravate the further injury of interlobular bile ducts.

Muscle performance and fatigue in compensated chronic liver disease.

Background: A common and debilitating symptom in patients with chronic liver disease is fatigue (CLD). Muscle dysfunction has been suggested to be a key mechanism of fatigue in CLD. Objective: We aimed to evaluate fatigue and the potential association with muscle performance and physical activity in outpatients with CLD. Methods: Two-hundred seventy outpatients with CLD were included, (52 ± 15 years, mean ± SD; 151 females) with autoimmune hepatitis (n = 49), primary biliary cholangitis (n = 45), primary sclerosing cholangitis (n = 46), chronic hepatitis B (n = 57) or C (n = 73). Patients with a Child-Pugh >6 were excluded. The questionnaire Fatigue Impact Scale (FIS) was used to evaluate fatigue, and physical activity was evaluated through a self-reported level of physical activity. Muscle function was assessed with four muscle tests, walking speed, handgrip strength, standing heel-rise test (SHT) and 'Timed Up and Go' test (TUG). Results: The median total FIS score was 30 (40% had FIS > 40, considered high-fatigue). Diminished muscle performance was observed in the SHT (% of predicted value: 53 ± 26%) and with maximum grip strength (85 ± 20%). The FIS score was significantly different between groups of CLDs (p = .004). In multivariate analysis the TUG (p = .001), SHT (p = .005), antidepressants (p < .001), and level of physical activity (p = .001) were associated with fatigue (R2 = 29%). Subjects with higher levels of physical activity had lower FIS (p < .001). Conclusions: In patients with CLD, fatigue was associated with low muscle performance and reduced level of physical activity, which could be a potential therapeutic target.