Ursodeoxycholic acid for treatment of primary sclerosing cholangitis: a placebo-controlled trial

Cilofexor in Patients With Compensated Cirrhosis Due to Primary Sclerosing Cholangitis: An Open-Label Phase 1B Study

INTRODUCTION

This proof-of-concept, open-label phase 1b study evaluated the safety and efficacy of cilofexor, a potent selective farnesoid X receptor agonist, in patients with compensated cirrhosis due to primary sclerosing cholangitis.

METHODS

Escalating doses of cilofexor (30 mg [weeks 1-4], 60 mg [weeks 5-8], 100 mg [weeks 9-12]) were administered orally once daily over 12 weeks. The primary endpoint was safety. Exploratory measures included cholestasis and fibrosis markers and pharmacodynamic biomarkers of bile acid homeostasis.

RESULTS

Eleven patients were enrolled (median age: 48 years; 55% men). The most common treatment-emergent adverse events (TEAEs) were pruritus (8/11 [72.7%]), fatigue, headache, nausea, and upper respiratory tract infection (2/11 [18.2%] each). Seven patients experienced a pruritus TEAE (one grade 3) considered drug-related. One patient temporarily discontinued cilofexor owing to peripheral edema. There were no deaths, serious TEAEs, or TEAEs leading to permanent discontinuation. Median changes (interquartile ranges) from baseline to week 12 (predose, fasting) were -24.8% (-35.7 to -7.4) for alanine transaminase, -13.0% (-21.9 to -8.6) for alkaline phosphatase, -43.5% (-52.1 to -30.8) for γ-glutamyl transferase, -12.7% (-25.0 to 0.0) for total bilirubin, and -21.2% (-40.0 to 0.0) for direct bilirubin. Least-squares mean percentage change (95% confidence interval) from baseline to week 12 at trough was -55.3% (-70.8 to -31.6) for C4 and -60.5% (-81.8 to -14.2) for cholic acid. Fasting fibroblast growth factor 19 levels transiently increased after cilofexor administration.

DISCUSSION

Escalating doses of cilofexor over 12 weeks were well tolerated and improved cholestasis markers in patients with compensated cirrhosis due to primary sclerosing cholangitis (NCT04060147).

New target-HMGCR inhibitors for the treatment of primary sclerosing cholangitis: A drug Mendelian randomization study

Background

No intervention definitively extends transplant-free survival in primary sclerosing cholangitis (PSC). Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), may enhance PSC prognosis, but their efficacy is debated.

Methods

We analyzed HMGCR single-nucleotide polymorphisms from published genome-wide association studies using Mendelian randomization to assess the causal relationship between HMGCR and PSC risk. Effects of HMGCR were compared with proprotein convertase subtilisin kexin 9 (PCSK9) inhibitors, common lipid-lowering drugs, using coronary heart disease risk as a positive control. The inverse-variance weighted (IVW) method was the primary analysis, complemented by the weighted median method. Heterogeneity analysis, examination of horizontal pleiotropy, and leave-one-out sensitivity analysis were conducted for result robustness.

Results

Genetically predicted HMGCR exhibited a pronounced detrimental effect on PSC in both the IVW method (odds ratio [OR] [95%] = 2.43 [1.23-4.78], P = 0.010) and the weighted median method (OR [95%] = 2.36 [1.02-5.45], P = 0.044). However, PCSK9 did not reach statistical significance. Moreover, all analyses passed through heterogeneity analysis, horizontal pleiotropy analysis, and leave-one-out sensitivity analysis.

Conclusion

This study has confirmed a causal relationship between HMGCR and PSC risk, suggesting statins targeting HMGCR could enhance PSC patient outcomes.

Network proximity analysis as a theoretical model for identifying potential novel therapies in primary sclerosing cholangitis

Primary Sclerosing Cholangitis (PSC) is a progressive cholestatic liver disease with no licensed therapies. Previous Genome Wide Association Studies (GWAS) have identified genes that correlate significantly with PSC, and these were identified by systematic review. Here we use novel Network Proximity Analysis (NPA) methods to identify already licensed candidate drugs that may have an effect on the genetically coded aspects of PSC pathophysiology.Over 2000 agents were identified as significantly linked to genes implicated in PSC by this method. The most significant results include previously researched agents such as metronidazole, as well as biological agents such as basiliximab, abatacept and belatacept. This in silico analysis could potentially serve as a basis for developing novel clinical trials in this rare disease.

Navigating the liver landscape: upcoming pharmacotherapies for primary sclerosing cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a bile duct disorder characterized by ductular reaction, hepatic inflammation, and liver fibrosis. The pathogenesis of PSC is still undefined, and treatment options for patients are limited. Previous clinical trials evaluated drug candidates targeting various cellular functions and pathways, such as bile acid signaling and absorption, gut bacteria and permeability, and lipid metabolisms. However, most of phase III clinical trials for PSC were disappointing, except vancomycin therapy, and there are still no established medications for PSC with efficacy and safety confirmed by phase IV clinical trials.

AREAS COVERED

This review summarizes the currently ongoing or completed clinical studies for PSC, which are phase II or further, and discusses therapeutic targets and strategies, limitations, and future directions and possibilities of PSC treatments. A literature search was conducted in PubMed and ClinicalTrials.gov utilizing the combination of the searched term 'primary sclerosing cholangitis' with other keywords, such as 'clinical trials,' 'antibiotics,' or drug names. Clinical trials at phase II or further were included for consideration.

EXPERT OPINION

Only vancomycin demonstrated promising therapeutic effects in the phase III clinical trial. Other drug candidates showed futility or inconsistent results, and the search for novel PSC treatments is still ongoing.

Novel preclinical developments of the primary sclerosing cholangitis treatment landscape

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease associated with inflammation, fibrosis, and destruction of intra- and extrahepatic bile ducts. Despite substantial recent advances in our understanding of PSC, the only proven treatment of PSC is liver transplantation. There is an urgent unmet need to find medical therapies for this disorder.

AREAS COVERED

Multiple drugs are currently under evaluation as therapeutic options for this disease. This article summarizes the literature on the various novel therapeutic options that have been investigated and are currently under development for the treatment of PSC.

EXPERT OPINION

In the next decade, more than one drug will likely be approved for the treatment of the disease, and we will be looking at combination therapies for the optimal management of the disease.

Microbial Players in Primary Sclerosing Cholangitis: Current Evidence and Concepts

Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease with progressive biliary inflammation, destruction of the biliary tract, and fibrosis, resulting in liver cirrhosis and end-stage liver disease. To date, liver transplantation is the only definitive treatment option for PSC. The precise etiology of PSC remains elusive, but it is widely accepted to involve a complex interplay between genetic predisposition, immunologic dysfunction, and environmental influence. In recent years, the gut-liver axis has emerged as a crucial pathway contributing to the pathogenesis of PSC, with particular focus on the role of gut microbiota. However, the role of the fungal microbiome or mycobiome has been overlooked for years, resulting in a lack of comprehensive studies on its involvement in PSC. In this review, we clarify the present clinical and mechanistic data and concepts concerning the gut bacterial and fungal microbiota in the context of PSC. This review sheds light on the role of specific microbes and elucidates the dynamics of bacterial and fungal populations. Moreover, we discuss the latest insights into microbe-altering therapeutic approaches involving the gut-liver axis and bile acid metabolism.

Machine-Learning-Guided Engineering of an NADH-Dependent 7β-Hydroxysteroid Dehydrogenase for Economic Synthesis of Ursodeoxycholic Acid

Enzymatic synthesis of ursodeoxycholic acid (UDCA) catalyzed by an NADH-dependent 7β-hydroxysteroid dehydrogenase (7β-HSDH) is more economic compared with an NADPH-dependent 7β-HSDH when considering the much higher cost of NADP+/NADPH than that of NAD+/NADH. However, the poor catalytic performance of NADH-dependent 7β-HSDH significantly limits its practical applications. Herein, machine-learning-guided protein engineering was performed on an NADH-dependent Rt7β-HSDHM0 from Ruminococcus torques. We combined random forest, Gaussian Naïve Bayes classifier, and Gaussian process regression with limited experimental data, resulting in the best variant Rt7β-HSDHM3 (R40I/R41K/F94Y/S196A/Y253F) with improvements in specific activity and half-life (40 °C) by 4.1-fold and 8.3-fold, respectively. The preparative biotransformation using a "two stage in one pot" sequential process coupled with Rt7β-HSDHM3 exhibited a space-time yield (STY) of 192 g L-1 d-1, which is so far the highest productivity for the biosynthesis of UDCA from chenodeoxycholic acid (CDCA) with NAD+ as a cofactor. More importantly, the cost of raw materials for the enzymatic production of UDCA employing Rt7β-HSDHM3 decreased by 22% in contrast to that of Rt7β-HSDHM0, indicating the tremendous potential of the variant Rt7β-HSDHM3 for more efficient and economic production of UDCA.

Current Therapeutics in Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is an orphan, cholestatic liver disease that is characterized by inflammatory biliary strictures with variable progression to end-stage liver disease. Its pathophysiology is poorly understood. Chronic biliary inflammation is likely driven by immune dysregulation, gut dysbiosis, and environmental exposures resulting in gut-liver crosstalk and bile acid metabolism disturbances. There is no proven medical therapy that alters disease progression in PSC, with the commonly prescribed ursodeoxycholic acid being shown to improve liver biochemistry at low-moderate doses (15-23 mg/kg/day) but not alter transplant-free survival or liver-related outcomes. Liver transplantation is the only option for patients who develop end-stage liver disease or refractory complications of PSC. Immunosuppressive and antifibrotic agents have not proven to be effective, but there is promise for manipulation of the gut microbiome with fecal microbiota transplantation and antibiotics. Bile acid manipulation via alternate synthetic bile acids such as norursodeoxycholic acid, or interaction at a transcriptional level via nuclear receptor agonists and fibrates have shown potential in phase II trials in PSC with several leading to larger phase III trials. In view of the enhanced malignancy risk, statins, and aspirin show potential for reducing the risk of colorectal cancer and cholangiocarcinoma in PSC patients. For patients who develop clinically relevant strictures with cholestatic symptoms and worsening liver function, balloon dilatation is safer compared with biliary stent insertion with equivalent clinical efficacy.

Beyond genome-wide association studies: Investigating the role of noncoding regulatory elements in primary sclerosing cholangitis

BACKGROUND

Genome-wide association studies (GWAS) have identified 30 risk loci for primary sclerosing cholangitis (PSC). Variants within these loci are found predominantly in noncoding regions of DNA making their mechanisms of conferring risk hard to define. Epigenomic studies have shown noncoding variants broadly impact regulatory element activity. The possible association of noncoding PSC variants with regulatory element activity has not been studied. We aimed to (1) determine if the noncoding risk variants in PSC impact regulatory element function and (2) if so, assess the role these regulatory elements have in explaining the genetic risk for PSC.

METHODS

Available epigenomic datasets were integrated to build a comprehensive atlas of cell type-specific regulatory elements, emphasizing PSC-relevant cell types. RNA-seq and ATAC-seq were performed on peripheral CD4+ T cells from 10 PSC patients and 11 healthy controls. Computational techniques were used to (1) study the enrichment of PSC-risk variants within regulatory elements, (2) correlate risk genotype with differences in regulatory element activity, and (3) identify regulatory elements differentially active and genes differentially expressed between PSC patients and controls.

RESULTS

Noncoding PSC-risk variants are strongly enriched within immune-specific enhancers, particularly ones involved in T-cell response to antigenic stimulation. In total, 250 genes and >10,000 regulatory elements were identified that are differentially active between patients and controls.

CONCLUSIONS

Mechanistic effects are proposed for variants at 6 PSC-risk loci where genotype was linked with differential T-cell regulatory element activity. Regulatory elements are shown to play a key role in PSC pathophysiology.

Current Therapies for Cholestatic Diseases

Cholestasis is a condition characterized by decrease in bile flow due to progressive pathological states that lead to chronic cholestatic liver diseases which affect the biliary tree at the intrahepatic level and extrahepatic level. They induce complications such as cirrhosis, liver failure, malignancies, bone disease and nutritional deficiencies that merit close follow-up and specific interventions. Furthermore, as those conditions progress to liver cirrhosis, there will be an increase in mortality but also an important impact in quality of life and economic burden due to comorbidities related with liver failure. Therefore, it is important that clinicians understand the treatment options for cholestatic liver diseases. With a general view of therapeutic options and their molecular targets, this review addresses the pathophysiology of cholangiopathies. The objective is to provide clinicians with an overview of the safety and efficacy of the treatment of cholangiopathies based on the current evidence.

Rhodopsin-associated retinal dystrophy: Disease mechanisms and therapeutic strategies

Rhodopsin is a light-sensitive G protein-coupled receptor that initiates the phototransduction cascade in rod photoreceptors. Mutations in the rhodopsin-encoding gene RHO are the leading cause of autosomal dominant retinitis pigmentosa (ADRP). To date, more than 200 mutations have been identified in RHO. The high allelic heterogeneity of RHO mutations suggests complicated pathogenic mechanisms. Here, we discuss representative RHO mutations as examples to briefly summarize the mechanisms underlying rhodopsin-related retinal dystrophy, which include but are not limited to endoplasmic reticulum stress and calcium ion dysregulation resulting from protein misfolding, mistrafficking, and malfunction. Based on recent advances in our understanding of disease mechanisms, various treatment methods, including adaptation, whole-eye electrical stimulation, and small molecular compounds, have been developed. Additionally, innovative therapeutic treatment strategies, such as antisense oligonucleotide therapy, gene therapy, optogenetic therapy, and stem cell therapy, have achieved promising outcomes in preclinical disease models of rhodopsin mutations. Successful translation of these treatment strategies may effectively ameliorate, prevent or rescue vision loss related to rhodopsin mutations.

Biological synthesis of ursodeoxycholic acid

Ursodeoxycholic acid (UDCA) is a fundamental treatment drug for numerous hepatobiliary diseases that also has adjuvant therapeutic effects on certain cancers and neurological diseases. Chemical UDCA synthesis is environmentally unfriendly with low yields. Biological UDCA synthesis by free-enzyme catalysis or whole-cell synthesis using inexpensive and readily available chenodeoxycholic acid (CDCA), cholic acid (CA), or lithocholic acid (LCA) as substrates is being developed. The free enzyme-catalyzed one-pot, one-step/two-step method uses hydroxysteroid dehydrogenase (HSDH); whole-cell synthesis, mainly uses engineered bacteria (mainly Escherichia coli) expressing the relevant HSDHs. To further develop these methods, HSDHs with specific coenzyme dependence, high enzyme activity, good stability, and high substrate loading concentration, P450 monooxygenase with C-7 hydroxylation activity and engineered strain harboring HSDHs must be exploited.

Ursodeoxycholic acid is associated with improved long-term outcome in patients with primary sclerosing cholangitis

BACKGROUND

It remains unclear whether ursodeoxycholic acid (UDCA) treatment improves long-term outcomes in patients with primary sclerosing cholangitis (PSC). In this study, we investigated whether UDCA treatment is associated with improved liver transplantation (LT)-free survival in a cohort of Japanese patients with PSC.Journal instruction requires a city and country for affiliations; however, these are missing in affiliation [6]. Please verify if the provided city and country are correct and amend if necessary.'Tokyo, Japan' is correct.

METHODS

We used retrospective data from the Japanese PSC registry that included 435 patients with PSC. In this study, we enrolled patients with a complete dataset at diagnosis, along with the diagnosis year, treatment protocol, follow-up period, and outcome data. The association between UDCA treatment and all-cause death or LT was analyzed using Cox regression and inverse probability of UDCA treatment weighting (IPTW)-adjusted Cox regression models adjusted for covariates.

RESULTS

Among 435 patients with PSC, 110 were excluded due to insufficient or missing data, and the remaining 325 patients (male, 187 (58%); mean age at diagnosis, 45.8 years) were enrolled. The mean follow-up period was 5.1 years, and 57 deaths and 24 LTs occurred during observation. UDCA was administered to 278 patients (86%). The Cox regression model demonstrated that UDCA treatment was associated with an improvement in LT-free survival [adjusted hazard ratio (aHR) 0.47, 95% confidence interval (CI) 0.28-0.78, p = 0.003]. In addition, the IPTW-adjusted model indicated a significant association between UDCA and LT-free survival (aHR 0.43, 95% CI 0.25-0.75, p = 0.020). Sensitivity analysis excluding patients treated with bezafibrate indicated a similarly significant association between UDCA treatment and LT-free survival.

CONCLUSION

In this Japanese PSC cohort, UDCA treatment was significantly associated with improved LT-free survival.

A Randomized, Dose-Finding, Proof-of-Concept Study of Berberine Ursodeoxycholate in Patients With Primary Sclerosing Cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a fibroinflammatory disease of the bile ducts leading to cirrhosis and hepatic decompensation. There are no approved pharmaceutical therapies for PSC. Berberine ursodeoxycholate (HTD1801) is an ionic salt of berberine and ursodeoxycholic acid with pleiotropic mechanisms of action.

METHODS

An 18-week proof-of-concept study was conducted to assess the safety and efficacy of HTD1801 in PSC. This study had three 6-week periods: (i) a placebo-controlled period, (ii) a treatment extension period, and (iii) a randomized treatment withdrawal period. The primary end point was change from baseline in alkaline phosphatase (ALP) at week 6.

RESULTS

Fifty-five patients were randomized and treated; 35 (64%) had inflammatory bowel disease and 22 (40%) had previously received ursodeoxycholic acid. Patients were initially randomized to placebo (n = 16), HTD1801 500 mg BID (n = 15), or HTD1801 1000 mg BID (n = 24). At baseline, mean (range) ALP values were 414 U/L (138-1,048), 397 U/L (237-773), and 335 U/L (122-882) for the placebo, HTD1801 500 mg BID, and HTD1801 1,000 mg BID groups, respectively. At week 6, a significant decrease in ALP was observed with HTD1801 (least square mean; HTD1801 500 mg BID = -53 U/L, P = 0.016; HTD1801 1000 mg BID = -37 U/L, P = 0.019) compared with placebo (98 U/L). ALP reductions were sustained through week 18 in those who remained on therapy, whereas ALP increased in those who crossed over to placebo during period 3. HTD1801 was generally well tolerated; 4 patients experienced serious adverse events, none attributed to HTD1801.

DISCUSSION

HTD1801 is associated with significant improvement in ALP and warrants further study as a treatment for PSC.

EASL Clinical Practice Guidelines on sclerosing cholangitis

Management of primary or secondary sclerosing cholangitis is challenging. These Clinical Practice Guidelines have been developed to provide practical guidance on debated topics including diagnostic methods, prognostic assessment, early detection of complications, optimal care pathways and therapeutic (pharmacological, endoscopic or surgical) options both in adults and children.

Safety and sustained efficacy of the farnesoid X receptor (FXR) agonist cilofexor over a 96-week open-label extension in patients with PSC

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is a major unmet medical need in clinical hepatology. Cilofexor is a nonsteroidal farnesoid X receptor agonist being evaluated for the treatment of PSC. Here, we describe the safety and preliminary efficacy of cilofexor in a 96-week, open-label extension (OLE) of a phase II trial.

METHODS

Noncirrhotic subjects with large-duct PSC who completed the 12-week, blinded phase of a phase II study (NCT02943460) were eligible, after a 4-week washout period, for a 96-week OLE with cilofexor 100 mg daily. Safety, liver biochemistry, and serum markers of fibrosis, cellular injury, and pharmacodynamic effects of cilofexor (fibroblast growth factor 19, C4, and bile acids [BAs]) were evaluated.

RESULTS

Among 52 subjects enrolled in the phase II study, 47 (90%) continued in the OLE phase (median age, 44 years; 60% male patients, 60% with inflammatory bowel disease, and 45% on ursodeoxycholic acid [UDCA]). At OLE baseline (BL), the median serum alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) were 368 U/L (interquartile range [IQR], 277-468 U/L) and 417 U/L (IQR, 196-801 U/L), respectively. Of the 47 subjects enrolled, 15 (32%) discontinued treatment prematurely (pruritus [n = 5], other adverse events [n = 5], subject decision/investigator discretion [n = 5]). At week 96, reductions in liver biochemistry parameters occurred, including serum ALP (median, -8.3% [IQR, -25.9% to 11.0%]; P = .066), GGT (-29.8% [IQR, -42.3% to -13.9%]; P < .001), alanine aminotransaminase (ALT) (-29.8% [IQR, -43.7% to -6.6%]; P = .002), and aspartate aminotransaminase (AST) (-16.7% [IQR, -35.3% to 1.0%]; P = .010), and rebounded after 4 weeks of untreated follow-up. ALP response (≥20% reduction from BL to week 96) was similar in the presence or absence of UDCA therapy (29% vs 39%; P = .71). At week 96, cilofexor treatment was associated with a significant reduction in serum 7α-hydroxy-4-cholesten-3-one (C4) (-29.8% [IQR, -64.3% to -8.5%]; P = .001). In subjects with detectable serum BAs at BL (n = 40), BAs decreased -23.9% (IQR, -44.4% to -0.6%; P = .006) at week 48 (n = 28) and -25.7% (IQR, -35.9% to 53.7%; P = .91) at week 96 (n = 26). Serum cytokeratin 18 (CK18) M30 and M65 were reduced throughout the OLE; significant reductions were observed at week 72 (CK18 M30, -17.3% [IQR, -39.3% to 8.8%]; P = .018; CK18 M65, -43.5% [IQR, -54.9% to 15.3%]; P = .096). At week 96, a small, but statistically significant absolute increase of 0.15 units in Enhanced Liver Fibrosis score was observed compared with BL (median, 9.34 vs 9.53; P = .028).

CONCLUSIONS

In this 96-week OLE of a phase II study of PSC, cilofexor was safe and improved liver biochemistry and biomarkers of cholestasis and cellular injury.

CLINICALTRIALS

gov identifier: NCT02943460.

Small duct primary sclerosing cholangitis: A discrete variant or a bridge to large duct disease, a practical review

The natural history, associations with inflammatory bowel disease (IBD), and long-term outcomes of large duct primary sclerosing cholangitis (ldPSC) have been well documented. Small duct primary sclerosing cholangitis (sdPSC) is a much less common and relatively more benign variant. The natural history of sdPSC has been difficult to characterize given the limited number of studies in the literature especially with regards to the subset of patients who progress to large duct involvement. It has been unclear whether sdPSC represented a subset of ldPSC, an earlier staging of ldPSC, or a completely separate and distinct entity of its own. Strong associations between sdPSC and IBD have been established with suspicion that concurrent sdPSC-IBD may be a key prognostic factor in determining which patients are at risk of progression to ldPSC. Little is known regarding the discrete circumstances that predisposes some patients with sdPSC to progress to ldPSC. It has been suspected that progression to large biliary duct involvement subjects this subset of patients to potentially developing life-threatening complications. Here the authors conducted a thorough review of the published sdPSC literature using Pubmed searches and cross-referencing to compile all accessible studies regarding cohorts of sdPSC patients in order better characterize the subset of sdPSC patients who progress to ldPSC and the associated outcomes.

The Covert Surge: Murine Bile Acid Levels Are Associated With Pruritus in Pediatric Autoimmune Sclerosing Cholangitis

OBJECTIVES

The exact etiology of pruritus in chronic cholestasis is unknown. Pruritus intensity does not correlate with common biochemical indices and there is a lack of biomarkers guiding diagnosis and treatment. We explored profiles of bile acids (BA) and muricholic acids (MCA) as well as autotaxin (ATX) antigen levels as potential circulating biomarkers of pruritus in pediatric patients.

METHODS

In 27 pediatric cholestatic patients [autoimmune sclerosing cholangitis (ASC) n = 20 (with pruritus n = 6, without pruritus n = 14); progressive familial intrahepatic cholestasis (PFIC) n = 7 (with pruritus n = 5, without pruritus n = 2)] and 23 age-matched controls pruritus was assessed by a visual analog scale of pruritus (PVAS). We obtained profiles of serum human BA including MCA using a mass-spectrometry assay and ATX antigen levels with a commercial ELISA.

RESULTS

PFIC and ASC patients exhibited significantly higher BA-, and MCA levels, than healthy controls, but only PFIC patients showed elevated ATX antigen levels higher [median: 1,650 ng/ml, interquartile rang (IQR): 776.9-3,742] compared to controls (median: 315.9 ng/ml, IQR: 251.1-417.2; PFIC p = 0.0003). ASC patients with pruritus showed only a minor increase in total BA (tBA) levels (median: 76.5 μmol/L, IQR: 54.7-205), but strikingly higher T-conjugated BA (median: 16.4 μmol/L, IQR: 8.9-41.4) and total MCA (tMCA) (median: 1.15 μmol/L, IQR: 0.77-2.44) levels compared to ASC patients without pruritus (tBA median: 24.3 μmol/L, IQR: 16.2-80.8; p < 0.0408; T-conjugated BA median: 1.3 μmol/L, IQR: 0.8-4.9; p = 0.0023; tMCA median: 0.30 μmol/L, IQR: 0.13-0.64, p = 0.0033). BA/MCA profiles distinctly differed depending on presence/absence of pruritus. Different from PFIC patients, ATX antigen levels were not significantly elevated in ASC patients with (median: 665.8 ng/ml, IQR: 357.8-1,203) and without pruritus (median: 391.0 ng/ml, IQR: 283.2-485.6). In ASC patients, tBA, tMCA, and ATX antigen levels did not correlate with pruritus severity.

CONCLUSION

Despite the same underlying disease, pediatric ASC patients with pruritus exhibit significantly altered BA profiles and MCA levels compared to ASC patients without pruritus. ATX antigen levels seem to have little diagnostic or prognostic meaning in ASC patients. An increased ATX activity alone seems not to be causal for pruritus genesis in ASC patients.

CLINICAL TRIAL REGISTRATION

[www.drks.de], identifier [DRKS00026913].

Degradation of Bile Acids by Soil and Water Bacteria

Bile acids are surface-active steroid compounds with a C5 carboxylic side chain at the steroid nucleus. They are produced by vertebrates, mainly functioning as emulsifiers for lipophilic nutrients, as signaling compounds, and as an antimicrobial barrier in the duodenum. Upon excretion into soil and water, bile acids serve as carbon- and energy-rich growth substrates for diverse heterotrophic bacteria. Metabolic pathways for the degradation of bile acids are predominantly studied in individual strains of the genera Pseudomonas, Comamonas, Sphingobium, Azoarcus, and Rhodococcus. Bile acid degradation is initiated by oxidative reactions of the steroid skeleton at ring A and degradation of the carboxylic side chain before the steroid nucleus is broken down into central metabolic intermediates for biomass and energy production. This review summarizes the current biochemical and genetic knowledge on aerobic and anaerobic degradation of bile acids by soil and water bacteria. In addition, ecological and applied aspects are addressed, including resistance mechanisms against the toxic effects of bile acids.

The Role of Microbiota in Primary Sclerosing Cholangitis and Related Biliary Malignancies

Primary sclerosing cholangitis (PSC) is an immune-related cholangiopathy characterized by biliary inflammation, cholestasis, and multifocal bile duct strictures. It is associated with high rates of progression to end-stage liver disease as well as a significant risk of cholangiocarcinoma (CCA), gallbladder cancer, and colorectal carcinoma. Currently, no effective medical treatment with an impact on the overall survival is available, and liver transplantation is the only curative treatment option. Emerging evidence indicates that gut microbiota is associated with disease pathogenesis. Several studies analyzing fecal and mucosal samples demonstrate a distinct gut microbiome in individuals with PSC compared to healthy controls and individuals with inflammatory bowel disease (IBD) without PSC. Experimental mouse and observational human data suggest that a diverse set of microbial functions may be relevant, including microbial metabolites and bacterial processing of pharmacological agents, bile acids, or dietary compounds, altogether driving the intrahepatic inflammation. Despite critical progress in this field over the past years, further functional characterization of the role of the microbiota in PSC and related malignancies is needed. In this review, we discuss the available data on the role of the gut microbiome and elucidate important insights into underlying pathogenic mechanisms and possible microbe-altering interventions.

The Management of Cholestatic Liver Diseases: Current Therapies and Emerging New Possibilities

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are two chronic cholestatic liver diseases affecting bile ducts that may progress to biliary cirrhosis. In the past few years, the increasing knowledge in the pathogenesis of both diseases led to a growing number of clinical trials and possible new targets for therapy. In this review, we provide an update on the treatments in clinical use and summarize the new drugs in trials for PBC and PSC patients. Farnesoid X Receptor (FXR) agonists and Pan-Peroxisome Proliferator-Activated Receptor (PPAR) agonists are the most promising agents and have shown promising results in both PBC and PSC. Fibroblast Growth Factor 19 (FGF19) analogues also showed good results, especially in PBC, while, although PBC and PSC are autoimmune diseases, immunosuppressive drugs had disappointing effects. Since the gut microbiome could have a potential role in the pathogenesis of PSC, recent research focused on molecules that could change the microbiome, with good results. The near future of the medical management of these diseases may include new treatments or a combination of multiple drugs targeting different signaling pathways at different stages of the diseases.

Recent advances in the treatment of primary sclerosing cholangitis

Introduction: PSC is a rare liver disease that leads frequently to cirrhosis and need for liver transplantation. No medical treatment is of proven value. Liver transplantation is the only curative therapy available. There is a big medical need to find medical therapy that can alter the natural history of the disease.Areas covered: The authors highlight advances in PSC, based on recent literature retrieved from PubMed until September 2020 regarding both medical and endoscopic biliary therapy.Future possibilities for treatment of PSC are discussed.Expert opinion: Biliary endoscopy is the cornerstone in the treatment of dominant strictures. Single-user peroral cholangioscopy is an emerging modality. Balloon dilatation therapy is the treatment of choice of dominant strictures. The most promising medical therapies showing efficacy in phase II trials are nor-Ursodeoxycholic acid, obethicolic acid, the non-steroidal FXR agonist Cilofexor and Aldafermin, a synthetic analogue of FGF-19. Antibiotics, particularly vancomycin have shown potential benefits, particularly in children but phase III studies are lacking. In observational studies of effects of biological therapy in patients with IBD/PSC adalimumab was associated with reduction in ALP. Results of liver transplantation are favorable but recurrence can be of clinical relevance particularly in patients transplanted before the age of 40.

Management of primary sclerosing cholangitis and its complications: an algorithmic approach

Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease, characterized by multiple strictures and dilatations of the intra- and extrahepatic bile ducts, leading to progressive liver fibrosis, in 10–15% cholangiocarcinoma, and ultimately end-stage liver disease. The pathogenesis is poorly understood, but (epi-)genetic factors, mechanisms of innate and adaptive immunity, toxic effects of hydrophobic bile acids, and possibly intestinal dysbiosis appear to be involved. The strong link with inflammatory bowel disease (IBD) is associated with a markedly enhanced risk of colorectal cancer which next to cholangiocarcinoma represents the most serious diagnostic challenge in long-term PSC management. Despite extensive research, no medical treatment has been proven so far to prolong the time to liver transplantation (LTx), which remains the effective treatment in late-stage disease. Recurrence of PSC after LTx is observed in up to 20% of patients. Here, we briefly summarize actual views on PSC pathogenesis and provide an algorithmic approach to diagnostic procedures and recommendations for the management of PSC and its complications. We describe promising treatment options subject to current clinical trials.

Pediatric Cholestatic Liver Disease: Review of Bile Acid Metabolism and Discussion of Current and Emerging Therapies

Cholestatic liver diseases are a significant cause of morbidity and mortality and the leading indication for pediatric liver transplant. These include diseases such as biliary atresia, Alagille syndrome, progressive intrahepatic cholestasis entities, ductal plate abnormalities including Caroli syndrome and congenital hepatic fibrosis, primary sclerosing cholangitis, bile acid synthesis defects, and certain metabolic disease. Medical management of these patients typically includes supportive care for complications of chronic cholestasis including malnutrition, pruritus, and portal hypertension. However, there are limited effective interventions to prevent progressive liver damage in these diseases, leaving clinicians to ultimately rely on liver transplantation in many cases. Agents such as ursodeoxycholic acid, bile acid sequestrants, and rifampicin have been mainstays of treatment for years with the understanding that they may decrease or alter the composition of the bile acid pool, though clinical response to these medications is frequently insufficient and their effects on disease progression remain limited. Recently, animal and human studies have identified potential new therapeutic targets which may disrupt the enterohepatic circulation of bile acids, alter the expression of bile acid transporters or decrease the production of bile acids. In this article, we will review bile formation, bile acid signaling, and the relevance for current and newer therapies for pediatric cholestasis. We will also highlight further areas of potential targets for medical intervention for pediatric cholestatic liver diseases.

Tauroursodeoxycholate protects from glycochenodeoxycholate-induced gene expression changes in perfused rat liver

Tauroursodeoxycholate (TUDC) is well known to protect against glycochenodeoxycholate (GCDC)-induced apoptosis in rat hepatocytes. In the present study, we analyzed whether TUDC also exerts protective effects by modulating GCDC-induced gene expression changes. For this, gene array-based transcriptome analysis and quantitative polymerase chain reaction (qPCR) were performed on RNA isolated from rat livers perfused with GCDC, TUDC or a combination of both (each 20 μm for 2 h). GCDC led to a significant increase of lactate dehydrogenase (LDH) into the effluent perfusate, which was prevented by TUDC. GCDC, TUDC and co-perfusion induced distinct gene expression changes. While GCDC upregulated the expression of several pro-inflammatory genes, co-perfusion with TUDC increased the expression of pro-proliferative and anti-apoptotic p53 target genes. In line with this, levels of serine20-phosphorylated p53 and of its target gene p21 were elevated by GCDC in a TUDC-sensitive way. GCDC upregulated the oxidative stress surrogate marker 8OH(d)G and the pro-apoptotic microRNAs miR-15b/16 and these effects were prevented by TUDC. The upregulation of miR-15b and miR-16 in GCDC-perfused livers was accompanied by a downregulation of several potential miR-15b and miR-16 target genes. The present study identified changes in the transcriptome of the rat liver which suggest, that TUDC is hepatoprotective by counteracting GCDC-induced gene expression changes.

Consensus guidelines: best practices for detection, assessment and management of suspected acute drug-induced liver injury occurring during clinical trials in adults with chronic cholestatic liver disease

BACKGROUND

Improved knowledge of the molecular pathophysiology and immunopathogenesis of cholestatic liver diseases in recent years has led to an increased interest in developing novel therapies. Patients with cholestatic liver disease often require different approaches to assessment and management of suspected drug-induced liver injury (DILI) compared to those with healthy livers and those with parenchymal liver diseases. At present, there are no regulatory guidelines or society position papers, that systematically address best practices pertaining to detection of DILI in these patients.

AIMS

To outline best practices for detection, assessment and management of suspected acute DILI during clinical trials in adults with the cholestatic liver diseases - Primary Biliary Cholangitis (PBC) and Primary Sclerosing Cholangitis (PSC).

METHODS

This is one of the several papers developed by the IQ DILI Initiative, which is comprised of members from 16 pharmaceutical companies, in collaboration with DILI experts from academia and regulatory agencies. The contents are the result of an extensive literature review, as well as in-depth discussions among industry, regulatory and academic DILI experts, to achieve consensus recommendations on DILI-related issues occurring during clinical trials for cholestatic liver diseases.

RESULTS

Recommended best practices are outlined pertaining to hepatic eligibility criteria, monitoring of liver tests, approach to a suspected DILI signal, and hepatic discontinuation rules.

CONCLUSIONS

This paper provides a framework for the approach to detection, assessment and management of suspected acute DILI occurring during clinical trials in adults with cholestatic liver disease.

Emerging therapies in primary sclerosing cholangitis: pathophysiological basis and clinical opportunities

Primary sclerosing cholangitis (PSC) is a progressive liver disease, histologically characterized by inflammation and fibrosis of the bile ducts, and clinically leading to multi-focal biliary strictures and with time cirrhosis and liver failure. Patients bear a significant risk of cholangiocarcinoma and colorectal cancer, and frequently have concomitant inflammatory bowel disease and autoimmune disease manifestations. To date, no medical therapy has proven significant impact on clinical outcomes and most patients ultimately need liver transplantation. Several treatment strategies have failed in the past and whilst prescription of ursodeoxycholic acid (UDCA) prevails, controversy regarding benefits remains. Lack of statistical power, slow and variable disease progression, lack of surrogate biomarkers for disease severity and other challenges in trial design serve as critical obstacles in the development of effective therapy. Advances in our understanding of PSC pathogenesis and biliary physiology over recent years has however led to a surge of clinical trials targeting various mechanistic compartments and currently raising hopes for imminent changes in patient management. Here, in light of pathophysiology, we outline and critically evaluate emerging treatment strategies in PSC, as tested in recent or ongoing phase II and III trials, stratified per a triad of targets of nuclear and membrane receptors regulating bile acid metabolism, immune modulators, and effects on the gut microbiome. Furthermore, we revisit the UDCA trials of the past and critically discuss relevant aspects of clinical trial design, including how the choice of endpoints, alkaline phosphatase in particular, may affect the future path to novel, effective PSC therapeutics.

Ursodeoxycholic acid in pregnancy?

The case of a 34-year-old woman with primary biliary cholangitis (PBC) before, during and after pregnancy is described. The use of ursodeoxycholic acid (UDCA) during and after pregnancy is discussed. UDCA has not been approved by the drug regulatory authorities as a pregnancy-safe drug; therefore, the reluctance of clinicians to prescribe UDCA during pregnancy is understandable. This Grand Round aims to provide a detailed analysis of the current evidence, safety data and clinical experience with UDCA (and alternative drugs) during pregnancy and lactation. Based on this analysis, advice for clinicians regarding the use of UDCA during pregnancy and lactation is given.

Validation, clinical utility and limitations of the Amsterdam-Oxford model for primary sclerosing cholangitis

BACKGROUND & AIMS

Recently the Amsterdam-Oxford model (AOM) was introduced as a prognostic model to assess the risk of death and/or liver transplantation (LT) in primary sclerosing cholangitis (PSC). We aimed to validate and assess the utility of the AOM.

METHODS

Clinical and laboratory data were collected from the time of PSC diagnosis until the last visit or time of LT or death. The AOM was calculated at yearly intervals following PSC diagnosis. Discriminatory performance was assessed by calculation of the C-statistic and prediction accuracy by comparing the predicted survival with the observed survival in Kaplan-Meier estimates. A grid search was performed to identify the most discriminatory AOM threshold.

RESULTS

A total of 534 patients with PSC and a mean (SD) age of 39.2 (13.1) years were included. The diagnosis was large duct PSC in 466 (87%), PSC with features of autoimmune hepatitis in 52 (10%) and small-duct PSC in 16 (3%). During the median (IQR) follow-up of 7.8 (4.0-12.6) years, 167 patients underwent LT and 65 died. The median LT-free survival was 13.2 (11.8-14.7) years. The C-statistic of the AOM ranged from 0.67 at baseline to 0.75 at 5 years of follow-up. The difference between the predicted and observed survival ranged from -1.6% at 1 year to + 3.9% at 5 years of follow-up. Patients that developed AOM scores >2.0 were at significant risk of LT or death (time-dependent hazard ratio 4.09; 95% CI 2.99-5.61).

CONCLUSIONS

In this large cohort of patients with PSC, the AOM showed an adequate discriminative performance and good prediction accuracy at PSC diagnosis and during follow-up. This study further validates the AOM as a valuable risk stratification tool in PSC and extends its utility.

LAY SUMMARY

In our study we assessed whether the Amsterdam-Oxford model (AOM) is able to correctly estimate the risk of liver transplantation or death in patients with primary sclerosing cholangitis (PSC). This model uses 7 objective and readily available variables to estimate prognosis for individual patients at the time of PSC diagnosis. The AOM may aid in patient counselling and timing of diagnostic procedures or therapeutic interventions for complications of liver disease. We confirm that the model works well at PSC diagnosis, but also when the AOM is recalculated at different timepoints during follow-up, greatly improving the applicability of the model in clinical practice and for individual patients.

The Nonsteroidal Farnesoid X Receptor Agonist Cilofexor (GS-9674) Improves Markers of Cholestasis and Liver Injury in Patients With Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) represents a major unmet medical need. In a phase II double-blind, placebo-controlled study, we tested the safety and efficacy of cilofexor (formerly GS-9674), a nonsteroidal farnesoid X receptor agonist in patients without cirrhosis with large-duct PSC. Patients were randomized to receive cilofexor 100 mg (n = 22), 30 mg (n = 20), or placebo (n = 10) orally once daily for 12 weeks. All patients had serum alkaline phosphatase (ALP) > 1.67 × upper limit of normal and total bilirubin ≤ 2 mg/dL at baseline. Safety, tolerability, pharmacodynamic effects of cilofexor (serum C4 [7α-hydroxy-4-cholesten-3-one] and bile acids), and changes in liver biochemistry and serum fibrosis markers were evaluated. Overall, 52 patients were randomized (median age 43 years, 58% male, 60% with inflammatory bowel disease, 46% on ursodeoxycholic acid). Baseline median serum ALP and bilirubin were 348 U/L (interquartile range 288-439) and 0.7 mg/dL (0.5-1.0), respectively. Dose-dependent reductions in liver biochemistry were observed. At week 12, cilofexor 100 mg led to significant reductions in serum ALP (median reduction -21%; P = 0.029 versus placebo), gamma-glutamyl transferase (-30%; P < 0.001), alanine aminotransferase (ALT) (-49%; P = 0.009), and aspartate aminotransferase (-42%; P = 0.019). Cilofexor reduced serum C4 compared with placebo; reductions in bile acids were greatest with 100 mg. Relative reductions in ALP were similar between ursodeoxycholic acid-treated and untreated patients. At week 12, cilofexor-treated patients with a 25% or more relative reduction in ALP had greater reductions in serum alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, tissue inhibitor of metalloproteinase 1, C-reactive protein, and bile acids than nonresponders. Adverse events were similar between cilofexor and placebo-treated patients. Rates of grade 2 or 3 pruritus were 14% with 100 mg, 20% with 30 mg, and 40% with placebo. Conclusion: In this 12-week, randomized, placebo-controlled study, cilofexor was well tolerated and led to significant improvements in liver biochemistries and markers of cholestasis in patients with PSC.

Review of pharmacotherapeutic treatments for primary sclerosing cholangitis

BACKGROUND

The objective of this review was to evaluate pharmacotherapeutic treatments for primary sclerosing cholangitis (PSC) through a literature search of current published data. A review of the current clinical data for each treatment is discussed.

METHODS

We conducted a systematic literature search for articles using EMBASE (1980 to April 1, 2018), and MEDLINE (1948 to April 1, 2018) using Ovid, to identify studies investigating various therapies in PSC. Search terms included the following: primary sclerosing cholangitis, cholangitis, sclerosing cholangitis; ursodeoxycholic acid, glucocorticoids, cyclosporine, tacrolimus, methotrexate, azathioprine, 6-mercaptopurine, penicillamine, anti-TNF, antibiotics, and probiotics. We also performed a review of current clinical trials using ClinicalTrials.gov. We considered for review relevant studies published in English, pilot studies, and randomized controlled trials involving human subjects.

RESULTS

Therapies that have been investigated in the management of PSC include those used in search terms and others that were not included in our search parameters. Analysis of published data involving each therapy was explored and none have shown any sustained, significant benefit in the treatment of PSC. In terms of relevance to patient care and clinical practice, this review evaluates and compares various pharmacotherapeutic treatments for PSC where liver transplantation remains the only definitive treatment.

CONCLUSIONS

To date, no clinical study of any drug has demonstrated effectiveness in terms of survival benefit or a decreased need for liver transplantation. More clinical studies are needed, and patients need to be adequately informed before any medical therapy for PSC is undertaken.

Pharmacologic management of primary sclerosing cholangitis: what's in the pipeline?

Introduction: Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease characterized by biliary inflammation, fibrosis, and stricturing. Although considered progressive, its course is difficult to predict, and there is currently no definitive therapy shown to alter disease course and prevent death or the need for liver transplantation. Areas covered: There are multiple agents in the pipeline targeting various pathways hypothesized to lead to and drive this disease. Some are already used for other treatment indications, including antibiotics such as oral vancomycin, metronidazole, and minocycline. Other agents including obeticholic acid, nor-ursodeoxycholic acid, and monoclonal antibodies are also under investigation. This narrative review focuses on the most recent published clinical trials available for discussion. We attempt to summarize the data on current and future treatment options. Expert opinion: The rarity of this condition and poor understanding of its pathophysiology have created a void for safe and effective treatment options to alter mortality or transplant free survival. Nevertheless, some agents currently being tested have demonstrated therapeutic potential. We await validation and prospective data on these agents in hopes of modifying the disease course for patients in the future.

British Society of Gastroenterology and UK-PSC guidelines for the diagnosis and management of primary sclerosing cholangitis

These guidelines on the management of primary sclerosing cholangitis (PSC) were commissioned by the British Society of Gastroenterology liver section. The guideline writing committee included medical representatives from hepatology and gastroenterology groups as well as patient representatives from PSC Support. The guidelines aim to support general physicians, gastroenterologists and surgeons in managing adults with PSC or those presenting with similar cholangiopathies which may mimic PSC, such as IgG4 sclerosing cholangitis. It also acts as a reference for patients with PSC to help them understand their own management. Quality of evidence is presented using the AGREE II format. Guidance is meant to be used as a reference rather than for rigid protocol-based care as we understand that management of patients often requires individual patient-centred considerations.

A novel prognostic model for transplant-free survival in primary sclerosing cholangitis

OBJECTIVE

Most prognostic models for primary sclerosing cholangitis (PSC) are based on patients referred to tertiary care and may not be applicable for the majority of patients with PSC. The aim of this study was to construct and externally validate a novel, broadly applicable prognostic model for transplant-free survival in PSC, based on a large, predominantly population-based cohort using readily available variables.

DESIGN

The derivation cohort consisted of 692 patients with PSC from the Netherlands, the validation cohort of 264 patients with PSC from the UK. Retrospectively, clinical and biochemical variables were collected. We derived the prognostic index from a multivariable Cox regression model in which predictors were selected and parameters were estimated using the least absolute shrinkage and selection operator. The composite end point of PSC-related death and liver transplantation was used. To quantify the models' predictive value, we calculated the C-statistic as discrimination index and established its calibration accuracy by comparing predicted curves with Kaplan-Meier estimates.

RESULTS

The final model included the variables: PSC subtype, age at PSC diagnosis, albumin, platelets, aspartate aminotransferase, alkaline phosphatase and bilirubin. The C-statistic was 0.68 (95% CI 0.51 to 0.85). Calibration was satisfactory. The model was robust in the sense that the C-statistic did not change when prediction was based on biochemical variables collected at follow-up.

CONCLUSION

The Amsterdam-Oxford model for PSC showed adequate performance in estimating PSC-related death and/or liver transplant in a predominantly population-based setting. The transplant-free survival probability can be recalculated when updated biochemical values are available.

Cholestatic liver diseases: new targets, new therapies

Cholestatic liver diseases result from gradual destruction of bile ducts, accumulation of bile acids and self-perpetuation of the inflammatory process leading to damage to cholangiocytes and hepatocytes. If left untreated, cholestasis will lead to fibrosis, biliary cirrhosis, and ultimately end-stage liver disease. Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the two most common chronic cholestatic liver diseases affecting adults, and their etiologies remain puzzling. While treatment with ursodeoxycholic acid (UDCA) has significantly improved outcomes and prolonged transplant-free survival for patients with PBC, treatment options for UDCA nonresponders remain limited. Furthermore, there is no available medical therapy for PSC. With recent advances in molecular biochemistry specifically related to bile acid regulation and understanding of immunologic pathways, novel pharmacologic treatments have emerged. In this review, we discuss the standard of care and emphasize the various emerging treatments for PBC and PSC.

Primary sclerosing cholangitis

Primary sclerosing cholangitis is a rare, chronic cholestatic liver disease characterised by intrahepatic or extrahepatic stricturing, or both, with bile duct fibrosis. Inflammation and fibrosis of bile ducts and the liver are followed by impaired bile formation or flow and progressive liver dysfunction. Patients might be asymptomatic at presentation or might have pruritus, fatigue, right upper quadrant pain, recurrent cholangitis, or sequelae of portal hypertension. The key diagnostic elements are cholestatic liver biochemistry and bile duct stricturing on cholangiography. Genetic and environmental factors are important in the cause of the disease, with the intestinal microbiome increasingly thought to play a pathogenetic role. Approximately 70% of patients have concurrent inflammatory bowel disease and patients require colonoscopic screening and surveillance. Primary sclerosing cholangitis is associated with increased malignancy risk and surveillance strategies for early cholangiocarcinoma detection are limited. No single drug has been proven to improve transplant-free survival. Liver transplantation is effective for advanced disease but at least 25% of patients develop recurrent disease in the graft.

Dominant strictures in primary sclerosing cholangitis: A multicenter survey of clinical definitions and practices

Dominant strictures (DSs) of the biliary tree occur in approximately 50% of patients with primary sclerosing cholangitis (PSC) and may cause significant morbidity. Nevertheless, the definition and management of DSs lacks consensus. We aimed to better understand current perceptions and practices regarding PSC‐associated DSs. We conducted an anonymous, 23‐question, survey‐based study wherein electronic surveys were distributed to 131 faculty in the Division of Gastroenterology and Hepatology at the three Mayo Clinic campuses (Rochester, Scottsdale, and Jacksonville) as well as the affiliated practice network. Responses were aggregated and compared, where applicable, to practice guidelines of the American Association for the Study of Liver Diseases and European Association for the Study of the Liver. A total of 54 faculty (41.2%) completed the survey, of whom 24 (44.4%) were hepatologists, 21 (38.9%) gastroenterologists, and 9 (16.7%) advanced endoscopists. One of the major study findings was that there was heterogeneity among participants' definition, evaluation, management, and follow‐up of DSs in PSC. The majority of participant responses were in accordance with societal practice guidelines, although considerable variation was noted. Conclusion: Despite the prevalence and morbidity of DSs in PSC, clinical perceptions and practices vary widely among hepatologists, gastroenterologists, and advanced endoscopists who manage these patients, even within a single health care system. Further studies are needed to address these variations, develop general and evidence‐based consensus, and increase adherence to societal guidelines. (Hepatology Communications 2018;2:836‐844)

Vedolizumab in patients with concurrent primary sclerosing cholangitis and inflammatory bowel disease does not improve liver biochemistry but is safe and effective for the bowel disease

BACKGROUND

Blocking of lymphocyte trafficking to bile ducts is a potential mechanism to alter the disease course of patients with primary sclerosing cholangitis (PSC).

AIM

To describe the effect of the α₄ β₇ integrin antibody, vedolizumab, on liver biochemistry and disease activity in patients with PSC and inflammatory bowel disease (IBD).

METHODS

This is a retrospective multi-centre study of adult patients with a diagnosis of both IBD and PSC. The primary outcome was change in serum alkaline phosphatase level at weeks 14 and 30. Secondary outcomes included changes in other liver biochemistries and in clinical outcomes for the bowel disease. A safety analysis for adverse events was performed.

RESULTS

Thirty-four patients (16 Crohn's disease, 18 ulcerative colitis) were included. Nine (26%) had a history of liver transplant. Median follow-up on vedolizumab was 9 months (IQR: 7-16). There was no overall change in serum alkaline phosphatase level with vedolizumab therapy (median 268 [IQR: 105-551] IU/L at baseline versus 249 [IQR: 183-634] IU/L, P = 0.99 at week 30). No significant changes in other liver biochemistries or the Mayo PSC Risk Score were demonstrated at week 30. Clinical remission was achieved at week 30 in 55% of Crohn's disease and 29% of ulcerative colitis patients. Seven (21%) patients ceased vedolizumab; six patients stopped therapy due to persistent IBD activity and one for worsening of liver biochemistries.

CONCLUSION

Vedolizumab treatment in patients with PSC and IBD did not improve liver biochemistry but was associated with improvement in bowel disease and a favourable safety profile.

The use of obeticholic acid for the management of non-viral liver disease: current clinical practice and future perspectives

Farnesoid X nuclear receptor is involved in the regulation of lipid and glucose metabolism, though mainly in the homeostasis of bile acids. Indeed, the agonists of farnesoid X nuclear receptor represent promising drugs. Areas covered: Obeticholic acid, a novel semisynthetic analogue of the naturally occurring bile acid, has led to encouraging preliminary results in both cholestatic and metabolic liver disease. In patients with primary biliary cholangitis, obeticholic acid determines a significant biochemical improvement although the effects on liver fibrosis are lacking. Obeticholic acid has been suggested for the treatment of nonalcoholic liver disease with good laboratory results. In cirrhotic animal models, the drug seems to reduce both portal hypertension and gut bacterial translocation. Expert commentary: The use of obeticholic acid for the treatment of primary biliary cholangitis shows satisfying results. However, some open questions remain unresolved. Herein, we provide an overview of the current knowledge about the use of obeticholic acid in the field of nonviral chronic liver diseases. We tried to give a global point of view using a translational approach.

Clinical guidelines for primary sclerosing cholangitis 2017

BACKGROUND

Primary sclerosing cholangitis (PSC) is relatively rare disease and pathogenesis and methods of treatments were still not established. Then, we had conducted the making clinical guidelines to manage patients with PSC based on the literature review and expert opinions. These clinical guidelines were made for the medical doctors on the management of PSC, except child case of PSC.

METHODS

We had employed modified Delphi method. The production committee decided guidelines, strength of recommendations and evidence level after reviewed literatures systematically, and The Expert panel evaluated those. The Scientific Committee of the Japan Biliary Association (JBA) evaluated revised guidelines, and the Public comments were collected on web site of JBA.

RESULTS

We had made 16 guidelines about epidemiology/pathophysiology, diagnostics, therapy and prognosis. Also, we had made both diagnostic and therapeutic flow chart.

CONCLUSIONS

We hope that these guidelines will contribute to the improvement and development of the medical care of PSC.

Primary sclerosing cholangitis - a comprehensive review

Primary sclerosing cholangitis (PSC) is a rare disorder characterised by multi-focal bile duct strictures and progressive liver disease. Inflammatory bowel disease is usually present and there is a high risk of cholangiocarcinoma and colorectal cancer. Most patients ultimately require liver transplantation, after which disease recurrence may occur. With limited therapeutic options and a lack of proven surveillance strategies, patients currently have significant unmet needs. In the present seminar, we provide a comprehensive review of the status of the field. We emphasise developments related to patient stratification and disease behaviour, and provide an overview of management options from a practical, patient-centered perspective. We survey advances made in the understanding of PSC pathogenesis and summarise the ongoing efforts to develop an effective therapy based on these insights.

Ursodeoxycholic acid for cystic fibrosis-related liver disease

BACKGROUND

Abnormal biliary secretion leads to the thickening of bile and the formation of plugs within the bile ducts; the consequent obstruction and abnormal bile flow ultimately results in the development of cystic fibrosis-related liver disease. This condition peaks in adolescence with up to 20% of adolescents with cystic fibrosis developing chronic liver disease. Early changes in the liver may ultimately result in end-stage liver disease with people needing transplantation. One therapeutic option currently used is ursodeoxycholic acid. This is an update of a previous review.

OBJECTIVES

To analyse evidence that ursodeoxycholic acid improves indices of liver function, reduces the risk of developing chronic liver disease and improves outcomes in general in cystic fibrosis.

SEARCH METHODS

We searched the Cochrane CF and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We also contacted drug companies and searched online trial registries.Date of the most recent search of the Group's trials register: 09 April 2017.

SELECTION CRITERIA

Randomised controlled trials of the use of ursodeoxycholic acid for at least three months compared with placebo or no additional treatment in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and quality. The authors used GRADE to assess the quality of the evidence.

MAIN RESULTS

Twelve trials have been identified, of which four trials involving 137 participants were included; data were only available from three of the trials (118 participants) since one cross-over trial did not report appropriate data. The dose of ursodeoxycholic acid ranged from 10 to 20 mg/kg/day for up to 12 months. The complex design used in two trials meant that data could only be analysed for subsets of participants. There was no significant difference in weight change, mean difference -0.90 kg (95% confidence interval -1.94 to 0.14) based on 30 participants from two trials. Improvement in biliary excretion was reported in only one trial and no significant change after treatment was shown. There were no data available for analysis for long-term outcomes such as death or need for liver transplantation.

AUTHORS' CONCLUSIONS

There are few trials assessing the effectiveness of ursodeoxycholic acid. The quality of the evidence identified ranged from low to very low. There is currently insufficient evidence to justify its routine use in cystic fibrosis.

norUrsodeoxycholic acid improves cholestasis in primary sclerosing cholangitis

BACKGROUND & AIM

Primary sclerosing cholangitis (PSC) represents a devastating bile duct disease, currently lacking effective medical therapy. 24-norursodeoxycholic acid (norUDCA) is a side chain-shortened C₂₃ homologue of UDCA and has shown potent anti-cholestatic, anti-inflammatory and anti-fibrotic properties in a preclinical PSC mouse model. A randomized controlled trial, including 38 centers from 12 European countries, evaluated the safety and efficacy of three doses of oral norUDCA (500mg/d, 1,000mg/d or 1,500mg/d) compared with placebo in patients with PSC.

METHODS

One hundred sixty-one PSC patients without concomitant UDCA therapy and with elevated serum alkaline phosphatase (ALP) levels were randomized for a 12-week treatment followed by a 4-week follow-up. The primary efficacy endpoint was the mean relative change in ALP levels between baseline and end of treatment visit.

RESULTS

norUDCA reduced ALP levels by -12.3%, -17.3%, and -26.0% in the 500, 1,000, and 1,500mg/d groups (p=0.029, p=0.003, and p<0.0001 when compared to placebo), respectively, while a +1.2% increase was observed in the placebo group. Similar dose-dependent results were found for secondary endpoints, such as ALT, AST, γ-GT, or the rate of patients achieving ALP levels <1.5× ULN. Serious adverse events occurred in seven patients in the 500mg/d, five patients in the 1,000mg/d, two patients in the 1500mg/d group, and three in the placebo group. There was no difference in reported pruritus between treatment and placebo groups.

CONCLUSIONS

norUDCA significantly reduced ALP values dose-dependently in all treatment arms. The safety profile of norUDCA was excellent and comparable to placebo. Consequently, these results justify a phase III trial of norUDCA in PSC patients. Lay summary: Effective medical therapy for primary sclerosing cholangitis (PSC) is urgently needed. In this phase II clinical study in PSC patients, a side chain-shortened derivative of ursodeoxycholic acid, norursodeoxycholic acid (norUDCA), significantly reduced serum alkaline phosphatase levels in a dose-dependent manner during a 12-week treatment. Importantly, norUDCA showed a favorable safety profile, which was similar to placebo. The use of norUDCA in PSC patients is promising and will be further evaluated in a phase III clinical study. ClinicalTrials.gov number: NCT01755507.

Emerging treatments for primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic, cholestatic, idiopathic liver disease that can progress to end-stage liver disease, cirrhosis and cholangiocarcinoma. PSC is an uncommon and highly heterogeneous disease, associated with inflammatory bowel disease and a complex pathophysiology. To date, no medical therapies have proved effective. The only available treatment for end-stage PSC is liver transplant, but recurrence is a significant complication. Areas covered: This review will explore previously tested treatments, discuss current treatment strategies and present viewpoints about future emerging therapies in PSC. We searched PubMed using the noted keywords. We included data from full-text articles published in English. Further relevant articles were identified from the reference lists of review articles. Expert commentary: The development of new therapies in PSC has been challenging. However, with greater awareness of the disease nowadays, new insights into the disease may help in the design of future therapeutic agents in PSC and ultimately in effective therapies.

Pharmacological interventions for primary sclerosing cholangitis: an attempted network meta-analysis

BACKGROUND

Primary sclerosing cholangitis is a chronic cholestatic liver disease that is associated with both hepatobiliary and colorectal malignancies, which can result in liver cirrhosis and its complications. The optimal pharmacological treatment for patients with primary sclerosing cholangitis remains controversial.

OBJECTIVES

To assess the comparative benefits and harms of different pharmacological interventions in people with primary sclerosing cholangitis by performing a network meta-analysis, and to generate rankings of available pharmacological interventions according to their safety and efficacy. Given that it was not possible to assess whether potential effect modifiers were similar across comparisons, we did not perform the network meta-analysis but instead used standard Cochrane methods.When trials begin to provide an adequate description of potential effect modifiers, we will attempt to conduct network meta-analysis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index - Expanded, the WHO International Clinical Trials Registry Platform, and randomised controlled trials registers until February 2017 to identify randomised clinical trials (RCT) on pharmacological interventions for primary sclerosing cholangitis.

SELECTION CRITERIA

We included only RCTs, irrespective of language, blinding, or publication status, in which participants were given a diagnosis of primary sclerosing cholangitis. We excluded trials that included previously liver-transplanted participants. We considered any of various pharmacological interventions compared with one other or with placebo. We excluded trials that compared different doses of various pharmacological interventions or that reported different treatment durations, except for ursodeoxycholic acid (UDCA). As UDCA is the drug most commonly investigated for primary sclerosing cholangitis, we performed a second analysis in which we stratified the dose of UDCA.

DATA COLLECTION AND ANALYSIS

We calculated the odds ratio and the rate ratio with 95% confidence intervals (CIs) using both fixed-effect and random-effects models based on available-participant analysis with Review Manager. We assessed risk of bias according to Cochrane, controlled risk of random errors with Trial Sequential Analysis, and assessed the quality of the evidence using GRADE.

MAIN RESULTS

We identified 22 RCTs in which 1211 participants were randomised to 13 different interventions. Most were placebo-controlled trials. Trials had few restrictions apart from an established diagnosis of primary sclerosing cholangitis, evidence of cholestasis, absence of decompensated liver disease, and absence of malignancy. However, some trials included symptomatic participants only, and others included both symptomatic and asymptomatic participants. A total of 11 RCTs (706 participants) provided data for one or more outcomes. The period of follow-up ranged from three months to three years in most trials. Only three trials reported follow-up longer than three years. Investigators found no evidence of differences in important clinical benefits such as reduction in mortality at maximal follow-up and improvement in health-related quality of life. Primary outcomes Mortality: Effect estimates: colchicine versus placebo: odds ratio 0.44, 95% CI 0.04 to 5.07, participants = 84, one trial; penicillamine versus placebo: odds ratio 1.18, 95% CI 0.39 to 3.58, participants = 70, one trial; steroids versus placebo: odds ratio 3.00, 95% CI 0.10 to 90.96, participants = 11, one trial; ursodeoxycholic acid versus placebo: odds ratio 1.51, 95% CI 0.63 to 3.63, participants = 348, two trials, I² = 0%; vancomycin versus placebo: not estimable because no events in either group, participants = 29, one trial. Serious adverse events (proportion): Effect estimates: infliximab versus placebo: odds ratio not estimable (because of zero events in both arms), participants = 7, one trial; steroids versus placebo: odds ratio 20.00, 95% CI 0.93 to 429.90, participants = 11, one trial; vancomycin versus placebo: not estimable because no events in either group, participants = 29, one trial. Serious adverse events (number): Effect estimates: infliximab versus placebo: rate ratio 0.80, 95% CI 0.02 to 40.44, participants = 7, one trial; penicillamine versus placebo: rate ratio 13.60, 95% CI 0.78 to 237.83, participants = 70, one trial; steroids versus placebo: rate ratio 3.32, 95% CI 0.71 to 15.62, participants = 11, one trial. Adverse events (proportion): Effect estimates: steroids versus placebo: odds ratio 20.00, 95% CI 0.93 to 429.90, participants = 11, one trial; ursodeoxycholic acid versus placebo: odds ratio 1.22, 95% CI 0.68 to 2.17, participants = 198, one trial; vancomycin versus placebo: not estimable because no events in either group, participants = 29, one trial. Adverse events (number): Effect estimates: cyclosporin versus placebo: rate ratio 2.64, 95% CI 0.99 to 7.03, participants = 26, one trial; steroids versus placebo: rate ratio 3.32, 95% CI 0.71 to 15.62, participants = 11, one trial; ursodeoxycholic acid plus metronidazole versus ursodeoxycholic acid: rate ratio 2.36, 95% CI 0.98 to 5.71, participants = 71, one trial. Health-related quality of life: ursodeoxycholic acid versus placebo: mean difference 1.30, 95% CI -5.61 to 8.21, participants = 198, one trial (Short Form (SF)-36 General Health Scale). Secondary outcomes Studies provided no evidence of differences in clinical benefits such as a reduction in the requirement for liver transplantation or a reduction in the incidence proportion of cholangiocarcinoma. One small trial (29 participants) comparing vancomycin versus placebo reported no malignancies, no liver decompensation, and no liver transplantation in either group after a very short follow-up period of 12 weeks after treatment. None of the remaining trials clearly reported other clinical benefits such as decreased development of all malignancies, colorectal cancer, liver decompensation, time to liver decompensation, time to liver transplantation, or requirement for cholecystectomy to allow comparisons between different interventions.

SOURCE OF FUNDING

Fifteen trials reported the source of funding; three were funded by parties without vested interest in results of the trial, and 12 were funded in part or in full by drug companies.

AUTHORS' CONCLUSIONS

Evidence is currently insufficient to show differences in effectiveness measures such as mortality, health-related quality of life, cirrhosis, or liver transplantation between any active pharmacological intervention and no intervention. However, trials were at high risk of bias and included small numbers of participants, had short follow-up periods, and reported few clinical outcomes. An urgent need exists to identify an effective medical treatment for primary sclerosing cholangitis through well-designed RCTs with adequate follow-up that aim to identify differences in outcomes important to people with primary sclerosing cholangitis.

Engineering 7β-Hydroxysteroid Dehydrogenase for Enhanced Ursodeoxycholic Acid Production by Multiobjective Directed Evolution

Ursodeoxycholic acid (UDCA) is the main active ingredient of natural bear bile powder with multiple pharmacological functions. 7β-Hydroxysteroid dehydrogenase (HSDH) is a key biocatalyst for the synthesis of UDCA. However, all the 7β-HSDHs reported commonly suffer from poor activity and thermostability, resulting in limited productivity of UDCA. In this study, a multiobjective directed evolution (MODE) strategy was proposed and applied to improve the activity, thermostability, and pH optimum of a 7β-HSDH. The best variant (V_3-1) showed a specific activity 5.5-fold higher than and a half-life 3-fold longer than those of the wild type. In addition, the pH optimum of the variant was shifted to a weakly alkaline value. In the cascade reaction, the productivity of UDCA with V_3-1 increased to 942 g L^-1 day^-1, in contrast to 141 g L^-1 day^-1 with the wild type. Therefore, this study provides a useful strategy for improving the catalytic efficiency of a key enzyme that significantly facilitated the bioproduction of UDCA.