Investigation into the efficacy of bezafibrate against primary biliary cirrhosis, with histological references from cases receiving long term monotherapy

Primary Biliary Cholangitis: Promising Emerging Innovative Therapies and Their Impact on GLOBE Scores

Primary biliary cholangitis (PBC), previously referred to as primary biliary cirrhosis, is an autoimmune disorder leading to the destruction of intra-hepatic bile ducts. If untreated, progressive bile duct damage and cholestasis can lead to ductopenia and result in cirrhosis. Ursodiol, the first drug approved for PBC, has changed the natural history of this disease and improved patient outcomes. Subsequently, several new prediction models incorporating a response to ursodiol were developed. These include the GLOBE score, which was shown to predict long-term outcomes in patients with PBC. In 2016, obeticholic acid (OCA) became the second drug to be approved by the FDA, predominantly based on improvement in alkaline phosphatase (ALP) levels. This trial has subsequently influenced the design of clinical trials. Several drugs are currently being evaluated as therapeutic options for PBC, with improvement in ALP being a main endpoint. In this review, we will discuss the impact of new therapies on GLOBE scores in patients with PBC.

The Inconvenient Truth of Primary Biliary Cholangitis/Autoimmune Hepatitis Overlap Syndrome

The term 'PBC/AIH-overlap' has been applied when features of autoimmune hepatitis (AIH), be they biochemical, serological or histological, coexist with primary biliary cholangitis (PBC), either at first presentation or sequentially during disease course. Several treatment paradigms have been proposed, extrapolated from those of the primary conditions. However, there are no randomised studies showing improved survival with combination therapy compared to bile acid monotherapy. In the absence of high-quality evidence, multidisciplinary patient-specific approaches must be used to individualise treatment pathways, with appreciation that disease phenotypes are not always static, differ in treatment responses, and have the potential to evolve over time.

Treatment of Primary Biliary Cholangitis: First-Line and Second-Line Therapies

Primary biliary cholangitis (PBC) is an autoimmune disease of the interlobular bile ducts leading to secondary damage of hepatocytes and may progress to cirrhosis and liver failure. The first-line treatment is ursodeoxycholic acid; up to 40% of patients do not have an adequate response and remain at risk of disease progression. Obeticholic acid has been conditionally approved for the treatment of PBC as add-on therapy and bezafibrate has shown similar efficacy in this group of patients. Several new therapies are in development and may further add to the treatment options available to patients with PBC.

Primary biliary cholangitis management: controversies, perspectives and daily practice implications from an expert panel

Primary biliary cholangitis (PBC) is a rare progressive immune-mediated liver disease that, if not adequately treated, may culminate in end-stage disease and need for transplantation. According to current guidelines, PBC is diagnosed in the presence of antimitochondrial antibodies (AMA) or specific antinuclear antibodies, and of a cholestatic biochemical profile, while biopsy is recommended only in selected cases. All patients receive ursodeoxycholic acid (UDCA) in first line; the only registered second-line therapy is obeticholic acid (OCA) for UDCA-inadequate responders. Despite the recent advances in understanding PBC pathogenesis and developing new treatments, many grey areas remain. Six Italian experts selected the following topics as the most urgent to address in PBC management: diagnosis and natural history of PBC: as a portion of the subjects with isolated AMA, normal alkaline phosphatase (ALP) levels and no symptoms of liver disease could have PBC by histology, defining how to manage and follow this population is crucial; role of liver biopsy: recent evidence suggests that biopsy may provide relevant information for risk stratification and prediction of UDCA response, possibly facilitating personalized approaches; risk stratification: the tools for risk stratification are well established, but some issues (eg bile acid dosage in routine practice) remain controversial; and therapy: those in more advanced stages of development are nuclear receptor modulators and fibrates, but more data are needed to plan personalized strategies. In this manuscript, for each topic, current evidence, controversies and future perspectives are summarized with the possible implications for clinical practice.

Current Treatment Options for Primary Biliary Cholangitis

Primary biliary cholangitis is a progressive, autoimmune disease of the interlobular bile ducts, leading to secondary damage of hepatocytes that may progress to cirrhosis and liver failure. Until recently, the only approved treatment was ursodeoxycholic acid. However, 40% of patients do not have an adequate response. Obeticholic acid was approved for treatment as add-on therapy in this group of patients. Off-label use of fibrates has also been reported to be effective. Several new therapies are in development and may further add to the treatment options available to patients with primary biliary cholangitis.

EASL Clinical Practice Guidelines: The diagnosis and management of patients with primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic inflammatory autoimmune cholestatic liver disease, which when untreated will culminate in end-stage biliary cirrhosis. Diagnosis is usually based on the presence of serum liver tests indicative of a cholestatic hepatitis in association with circulating antimitochondrial antibodies. Patient presentation and course can be diverse and risk stratification is important to ensure all patients receive a personalised approach to their care. The goals of treatment and management are the prevention of end-stage liver disease, and the amelioration of associated symptoms. Pharmacologic approaches in practice, to reduce the impact of the progressive nature of disease, currently include licensed therapies (ursodeoxycholic acid and obeticholic acid) and off-label therapies (fibric acid derivatives, budesonide). These clinical practice guidelines summarise the evidence for the importance of a structured, life-long and individualised, approach to the care of patients with PBC, providing a framework to help clinicians diagnose and effectively manage patients.

Fibrates for the treatment of cholestatic itch (FITCH): study protocol for a randomized controlled trial

BACKGROUND

Pruritus (itch) is a frequent, burdensome and difficult-to-treat symptom in patients with cholestasis. Fibrates are currently under investigation for the treatment of primary biliary cholangitis in patients with a suboptimal response to ursodeoxycholic acid. Moreover, there is empirical evidence for a possible antipruritic effect. We aim to prove this in a randomized controlled trial, including patients with cholestatic liver diseases other than primary biliary cholangitis that are accompanied by pruritus.

METHODS

A multicenter investigator-initiated, double-blind, randomized placebo-controlled trial to evaluate the effect of bezafibrate on cholestatic pruritus in 84 adult patients with primary biliary cholangitis or primary/secondary sclerosing cholangitis. Primary outcome is the proportion of patients with a reduction of itch intensity of 50% or more (measured on a Visual Analog Scale) after 21 days of treatment with bezafibrate 400 mg qid or placebo. Secondary outcomes include the effect of bezafibrate on a five-dimensional itch score, liver disease-specific quality of life, serum liver tests and autotaxin activity. Safety will be evaluated through serum parameters for kidney function and rhabdomyolysis as well as precise recording of (serious) adverse events. We provide a schematic overview of the study protocol and describe the methods used to recruit and randomize patients, collect and handle data and perform statistical analyses.

DISCUSSION

Given its favorable safety profile and anticholestatic properties, bezafibrate may become the new first-line treatment option for treating cholestatic pruritus.

TRIAL REGISTRATION

Netherlands Trial Register, ID: NCT02701166 . Registered on 2 March 2016; Netherlands Trial Register, ID: NTR5436 . Registered on 3 August 2015.

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

BACKGROUND

Primary biliary cholangitis (previously primary biliary cirrhosis) is a chronic liver disease caused by the destruction of small intra-hepatic bile ducts resulting in stasis of bile (cholestasis), liver fibrosis, and liver cirrhosis. The optimal pharmacological treatment of primary biliary cholangitis remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different pharmacological interventions in the treatment of primary biliary cholangitis through a network meta-analysis and to generate rankings of the available pharmacological interventions according to their safety and efficacy. However, it was not possible to assess whether the potential effect modifiers were similar across different comparisons. Therefore, we did not perform the network meta-analysis, and instead, assessed the comparative benefits and harms of different interventions using standard Cochrane methodology.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and randomised controlled trials registers to February 2017 to identify randomised clinical trials on pharmacological interventions for primary biliary cholangitis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in participants with primary biliary cholangitis. We excluded trials which included participants who had previously undergone liver transplantation. We considered any of the various pharmacological interventions compared with each other or with placebo or no intervention.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the odds ratio (OR) and rate ratio with 95% confidence intervals (CI) using both fixed-effect and random-effects models based on available-participant analysis with Review Manager 5. 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 74 trials including 5902 participants that met the inclusion criteria of this review. A total of 46 trials (4274 participants) provided information for one or more outcomes. All the trials were at high risk of bias in one or more domains. Overall, all the evidence was low or very low quality. The proportion of participants with symptoms varied from 19.9% to 100% in the trials that reported this information. The proportion of participants who were antimitochondrial antibody (AMA) positive ranged from 80.8% to 100% in the trials that reported this information. It appeared that most trials included participants who had not received previous treatments or included participants regardless of the previous treatments received. The follow-up in the trials ranged from 1 to 96 months.The proportion of people with mortality (maximal follow-up) was higher in the methotrexate group versus the no intervention group (OR 8.83, 95% CI 1.01 to 76.96; 60 participants; 1 trial; low quality evidence). The proportion of people with mortality (maximal follow-up) was lower in the azathioprine group versus the no intervention group (OR 0.56, 95% CI 0.32 to 0.98; 224 participants; 2 trials; I2 = 0%; low quality evidence). However, it has to be noted that a large proportion of participants (25%) was excluded from the trial that contributed most participants to this analysis and the results were not reliable. There was no evidence of a difference in any of the remaining comparisons. The proportion of people with serious adverse events was higher in the D-penicillamine versus no intervention group (OR 28.77, 95% CI 1.57 to 526.67; 52 participants; 1 trial; low quality evidence). The proportion of people with serious adverse events was higher in the obeticholic acid plus ursodeoxycholic acid (UDCA) group versus the UDCA group (OR 3.58, 95% CI 1.02 to 12.51; 216 participants; 1 trial; low quality evidence). There was no evidence of a difference in any of the remaining comparisons for serious adverse events (proportion) or serious adverse events (number of events). None of the trials reported health-related quality of life at any time point.

FUNDING

nine trials had no special funding or were funded by hospital or charities; 31 trials were funded by pharmaceutical companies; and 34 trials provided no information on source of funding.

AUTHORS' CONCLUSIONS

Based on very low quality evidence, there is currently no evidence that any intervention is beneficial for primary biliary cholangitis. However, the follow-up periods in the trials were short and there is significant uncertainty in this issue. Further well-designed randomised clinical trials are necessary. Future randomised clinical trials ought to be adequately powered; performed in people who are generally seen in the clinic rather than in highly selected participants; employ blinding; avoid post-randomisation dropouts or planned cross-overs; should have sufficient follow-up period (e.g. five or 10 years or more); and use clinically important outcomes such as mortality, health-related quality of life, cirrhosis, decompensated cirrhosis, and liver transplantation. Alternatively, very large groups of participants should be randomised to facilitate shorter trial duration.

Emerging drugs for the treatment of Primary Biliary Cholangitis

INTRODUCTION

Primary biliary cholangitis (PBC) is an autoimmune chronic disease of the liver that can progress to cirrhosis and hepatocellular carcinoma. It affects approximately 1 in 4,000 with a 10:1 female to male ratio. The diagnosis of PBC can be made based on serum antimitochondrial antibodies (AMA) in a patient with abnormally high serum alkaline phosphatase after ruling out other causes of cholestasis and biliary obstruction. Genome-wide association studies have revealed several human leukocyte antigen (HLA) and non-HLA risk loci in PBC, and complex environmental-host immunogenetic interactions are believed to underlie the etiopathogenesis of the disease. Fatigue and pruritus are the most common and often problematic symptoms; although often mild, these can be severe and life-alternating in a subset of patients. Ursodeoxycholic acid (UDCA) is the only drug approved by the United States Food and Drug Administration for the treatment of PBC. Clinical trials have shown that UDCA significantly improves transplant-free survival. However, nearly 40% of PBC patients do not respond adequately to PBC and are at higher risk for serious complications when compared to PBC patients with complete response to UDCA.

AREAS COVERED

Here we provide a detailed discussion regarding novel therapeutic agents and potential areas for further investigation in PBC-related research.

EXPERT OPINION

Results of ongoing clinical trials and emerging treatment paradigms for PBC will likely further improve medical management of this disorder in the near future.

Systematic review and meta-analysis: bezafibrate in patients with primary biliary cirrhosis

BACKGROUND AND AIM

Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cirrhosis (PBC), but not all cases respond well. Evidence has shown that combination therapy of UDCA with bezafibrate significantly improved liver function. A meta-analysis was performed to assess the efficacy and safety of UDCA and bezafibrate combination therapy in the treatment of PBC.

RESULTS

Nine trials, with a total of 269 patients, were included in the analysis. The bias risk of these trials was high. Compared with UDCA alone, the combination with bezafibrate improved the Mayo risk score (mean difference [MD], 0.60; 95% confidence interval [CI], 0.25-0.95; P=0.0008) and liver biochemistry: alkaline phosphatase (MD, -238.21 IU/L; 95% CI, -280.83 to -195.60; P<0.00001); gamma-glutamyltransferase (MD, -38.23 IU/L; 95% CI, -50.16 to -25.85; P<0.00001); immunoglobulin M (MD, -128.63 IU/L; 95% CI, -151.55 to -105.71; P<0.00001); bilirubin (MD, -0.20 mg/dL; 95% CI, -0.33 to -0.07; P=0.002); triglycerides (MD, -26.84 mg/dL; 95% CI, -36.51 to -17.17; P<0.0001); total cholesterol (MD, -21.58 mg/dL; 95% CI, -30.81 to -12.34; P<0.0001), and serum alanine aminotransferase (MD, -10.24 IU/L; 95% CI, -12.65 to -78.5; P<0.00001). However, combination therapy showed no significant differences in the incidence of all-cause mortality or pruritus, and may have resulted in more adverse events (risk ratio [RR], 0.22; 95% CI, 0.07-0.67; P=0.008).

CONCLUSION

Combination therapy improved liver biochemistry and the prognosis of PBC, but did not improve clinical symptoms or incidence of death. Attention should be paid to adverse events when using bezafibrate.

Autoantibody status and histological variables influence biochemical response to treatment and long-term outcomes in Japanese patients with primary biliary cirrhosis

AIM

The aim of the present study is to evaluate the factors influencing biochemical response to treatment and the value of biochemical response for predicting long-term outcomes in Japanese patients with primary biliary cirrhosis (PBC).

METHODS

Biochemical response to ursodeoxycholic acid (UDCA) or UDCA plus bezafibrate was defined as good (≤upper limit of normal [ULN]), fair (≤1.5 × ULN) or poor (>1.5 × ULN) at 2 years after initiation of UDCA treatment. Associations between various factors (including age, sex, autoantibody status and histological variables at baseline), biochemical response to treatment and long-term outcomes were evaluated in 164 Japanese PBC patients.

RESULTS

Anti-gp210 positivity and a higher bile duct loss score were significant risk factors for worse alkaline phosphatase (ALP) response (odds ratios [OR], 2.78 and 1.85, respectively). Age, anti-gp210 positivity and anticentromere positivity were significant risk factors for worse alanine aminotransferase (ALT) response (OR, 1.05, 4.0 and 2.77, respectively). Anti-gp210 positivity and a higher hepatitis score were significant risk factors for worse immunoglobulin (Ig)M response (OR, 2.10 and 2.06, respectively). Worse ALP and IgM response were significant risk factors for progression to late-stage disease without jaundice (OR, 2.27 and 2.32, respectively). Worse ALT response was a significant risk factor for progression to late-stage disease with persistent jaundice (OR, 11.11).

CONCLUSION

Biochemical response to treatment at 2 years, which is influenced by autoantibody status and histological variables at baseline, can predict long-term outcomes in Japanese patients with PBC.

Fibrates and cholestasis

Cholestasis, including primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), results from an impairment or disruption of bile production and causes intracellular retention of toxic bile constituents, including bile salts. If left untreated, cholestasis leads to liver fibrosis and cirrhosis, which eventually results in liver failure and the need for liver transplantation. Currently, the only therapeutic option available for these patients is ursodeoxycholic acid (UDCA), which slows the progression of PBC, particularly in stage I and II of the disease. However, some patients have an incomplete response to UDCA therapy, whereas other, more advanced cases often remain unresponsive. For PSC, UDCA therapy does not improve survival, and recommendations for its use remain controversial. These considerations emphasize the need for alternative therapies. Hepatic transporters, located along basolateral (sinusoidal) and apical (canalicular) membranes of hepatocytes, are integral determinants of bile formation and secretion. Nuclear receptors (NRs) are critically involved in the regulation of these hepatic transporters and are natural targets for therapy of cholestatic liver diseases. One of these NRs is peroxisome proliferator-activated receptor alpha (PPARα), which plays a central role in maintaining cholesterol, lipid, and bile acid homeostasis by regulating genes responsible for bile acid synthesis and transport in humans, including cytochrome P450 (CYP) isoform 7A1 (CYP7A1), CYP27A1, CYP8B1, uridine 5'-diphospho-glucuronosyltransferase 1A1, 1A3, 1A4, 1A6, hydroxysteroid sulfotransferase enzyme 2A1, multidrug resistance protein 3, and apical sodium-dependent bile salt transporter. Expression of many of these genes is altered in cholestatic liver diseases, but few have been extensively studied or had the mechanism of PPARα effect identified. In this review, we examine what is known about these mechanisms and consider the rationale for the use of PPARα ligand therapy, such as fenofibrate, in various cholestatic liver disorders.

Clinical application of transcriptional activators of bile salt transporters

Hepatobiliary bile salt (BS) transporters are critical determinants of BS homeostasis controlling intracellular concentrations of BSs and their enterohepatic circulation. Genetic or acquired dysfunction of specific transport systems causes intrahepatic and systemic retention of potentially cytotoxic BSs, which, in high concentrations, may disturb integrity of cell membranes and subcellular organelles resulting in cell death, inflammation and fibrosis. Transcriptional regulation of canalicular BS efflux through bile salt export pump (BSEP), basolateral elimination through organic solute transporters alpha and beta (OSTα/OSTβ) as well as inhibition of hepatocellular BS uptake through basolateral Na(+)-taurocholate cotransporting polypeptide (NTCP) represent critical steps in protection from hepatocellular BS overload and can be targeted therapeutically. In this article, we review the potential clinical implications of the major BS transporters BSEP, OSTα/OSTβ and NTCP in the pathogenesis of hereditary and acquired cholestatic syndromes, provide an overview on transcriptional control of these transporters by the key regulatory nuclear receptors and discuss the potential therapeutic role of novel transcriptional activators of BS transporters in cholestasis.

Fibrate treatment for primary biliary cirrhosis

PURPOSE OF REVIEW

Primary biliary cirrhosis (PBC) can lead to end-stage liver disease and death. Ursodeoxycholic acid (UDCA) treatment can normalize serum liver enzymes in PBC, and such UDCA-responsive patients have a similar life expectancy as age and sex-matched controls. Nearly up to 50% of the patients with PBC, depending on sex and age at diagnosis, show an incomplete biochemical response to UDCA and require additional/alternative treatment. The purpose of this review is to critically evaluate the molecular mechanisms and clinical benefit of fibrate treatment in these patients.

RECENT FINDINGS

Fibrates have anticholestatic, anti-inflammatory, and antifibrotic effects in animal and in-vitro studies. The mechanisms that underlie these effects are complementary, and largely mediated through activation of peroxisome proliferator activated receptors. Fibrate treatment ameliorated liver biochemical tests in UDCA unresponsive patients, either as mono-therapy or in combination with UDCA. These results, however, were obtained in case series and small pilot studies. The results of phase III studies, such as the Bezafibrate in Combination With Ursodeoxycholic Acid in Primary Biliary Cirrhosis (BEZURSO) trial, are currently awaited.

SUMMARY

A considerable body of observational evidence supports the safety and efficacy of fibrate treatment in PBC patients with an incomplete response to UDCA. These results encourage the evaluation of its effects on liver-related morbidity and mortality in larger clinical trials.

Effects of three different fibrates on intrahepatic cholestasis experimentally induced in rats

Background. Activation of PPAR α modulates cholesterol metabolism and suppresses bile acid synthesis. This study aims to evaluate the effect of PPAR α agonists, fenofibrate, bezafibrate, and gemfibrozil, on acute cholestasis induced by ethinylestradiol (EE) plus chlorpromazine (CPZ) in rats. Method. 100 male albino rats (150-200 gm) were divided randomly into 10 equal groups. Control group received 1% methylcellulose vehicle; disease group received CPZ plus EE for 5 consecutive days; four groups received either ursodeoxycholic acid, fenofibrate, bezafibrate, or gemfibrozil for 7 days; 2 days before EE + CPZ, three other groups received one of the three fibrates after GW6471, a selective PPAR α antagonist in addition to EE + CPZ. The final group received GW6471 alone. Results. The three fibrates showed marked reduction (P < 0.05) in serum levels of ALP, GGT, ALT, AST, total bile acids, bilirubin, TNF α , and IL-1 β and in hepatic malondialdehyde level as well as a significant increase in bile flow rate (P < 0.05) in addition to improvements in histopathological parameters compared to diseased group. In groups which received GW6471, these effects were completely abolished with fenofibrate and partially blocked with bezafibrate and gemfibrozil. Conclusion. Short-term administration of fibrates to EE/CPZ-induced intrahepatic cholestatic rats exerted beneficial effects on hepatocellular damage and apoptosis. Fenofibrate anticholestatic effect was solely PPAR α dependent while other mechanisms played part in bezafibrate and gemfibrozil actions.

Treatment of autoimmune liver disease: current and future therapeutic options

Autoimmune liver disease spans three predominant processes, from the interface hepatitis of autoimmune hepatitis to the lymphocytic cholangitis of primary biliary cirrhosis, and finally the obstructive fibrosing sclerotic cholangiopathy of primary sclerosing cholangitis. Although all autoimmune in origin, they differ in their epidemiology, presentation and response to immunosuppressive therapy and bile acid based treatments. With an ongoing better appreciation of disease aetiology and pathogenesis, treatment is set ultimately to become more rational. We provide an overview of current and future therapies for patients with autoimmune liver disease, with an emphasis placed on some of the evidence that drives current practice.

Bezafibrate maintenance therapy in patients with advanced chronic hepatitis C

BACKGROUND

Bezafibrate exerts multiple effects on lipid metabolism by activating the peroxisome proliferator-activated receptor-α, which modulates the expression of key genes of lipid transport, lipoprotein metabolism as well as inflammation. The aim of the present study was to assess the efficacy and safety of bezafibrate in patients with advanced chronic hepatitis C.

MATERIALS AND METHODS

A total of 34 patients received oral bezafibrate treatment (400 mg/day) on the basis of a prospective observational open-label study design. Clinical, biochemical and virological data were evaluated during a mean treatment duration of 19 months. In a subpopulation (n=8), cytokine expression analysis was carried out and compared with an hepatitis C virus treatment-naive control group (n=7).

RESULTS

A significant improvement in aspartate aminotransferase (P=0.007), alanine aminotransferase (P<0.0001), alkaline phosphatase (P=0.001), γ-glutamyltranspeptidase levels (P=0.001) and aspartate aminotransferase-to-platelets ratio index Score (P=0.026) could be found at the end of observation. No significant effect on viral load was observed. Bezafibrate treatment for at least 4 months markedly increased interferon-γ expression compared with the treatment-naive patients (4.81 vs. 1.63 arbitrary units; P=0.005), whereas tumour necrosis factor-α and interleukin-6 levels were not significantly influenced.

CONCLUSION

This observational study provides evidence that bezafibrate is effective for patients with advanced chronic hepatitis C by reducing liver enzymes significantly and should be further evaluated as a potentially beneficial maintenance therapy.

Nuclear receptors as drug targets in cholestatic liver diseases

Cholestatic liver diseases encompass a wide spectrum of disorders with different causes, resulting in impaired bile flow and accumulation of bile acids and other potentially hepatotoxic cholephils. The understanding of the molecular mechanisms of bile formation and cholestasis has recently improved significantly through new insights into nuclear receptor (patho)biology. Nuclear receptors are ligand-activated transcription factors, which act as central players in the regulation of genes responsible for elimination and detoxification of biliary constituents accumulating in cholestasis. They also control other pathophysiologic processes such as inflammation, fibrogenesis, and carcinogenesis involved in the pathogenesis and disease progression of cholestasis liver diseases.

Bezafibrate for primary biliary cirrhosis

BACKGROUND

Treatment of primary biliary cirrhosis is complicated. There are studies suggesting that bezafibrate, alone or in combination with ursodeoxycholic acid (UDCA), is effective in the treatment of primary biliary cirrhosis, but no systematic review has summarised the evidence yet.

OBJECTIVES

To assess the beneficial and harmful effects of bezafibrate in patients with primary biliary cirrhosis.

SEARCH METHODS

The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, LILACS, Clinicaltrials.gov, the WHO International Clinical Trials Registry Platform, and full text searches were conducted until November 2011. The searches in Chinese Bio-medical Literature Database, China Network Knowledge Information, Chinese Science Journal Database, Chinese Medical Citation Index, Wanfang Database, and full text searches were conducted until January 2011. Manufacturers and authors were contacted.

SELECTION CRITERIA

All randomised clinical trials comparing bezafibrate at any dose or regimen in patients with primary biliary cirrhosis with placebo or no intervention, or with another drug. Any concomitant interventions were allowed if received equally by all treatment groups in a trial.

DATA COLLECTION AND ANALYSIS

Two authors extracted data. RevMan Analysis was used for statistical analysis of dichotomous data with risk ratio (RR) or risk difference (RD), and of continuous data with mean difference (MD), both with 95% confidence intervals (CI). Methodological domains were used to assess risk of systematic errors (bias). Trial sequential analysis was used to control for random errors (play of chance).

MAIN RESULTS

Six trials with 151 Japanese patients were included. All trials had high risk of bias. Four trials compared bezafibrate plus UDCA with no intervention plus UDCA (referenced as bezafibrate versus no intervention in the remaining text), and two trials compared bezafibrate with UDCA. No patient died and no patient developed liver-related complications in any of the included trials. Bezafibrate was without significant effects on the occurrence of adverse events compared with no intervention (5/32 (16%) versus 0/28 (0%)) (RR 5.40, 95% CI 0.69 to 42.32; 3 trials with 60 patients; I² = 0%) or with UDCA (2/32 (6%) versus 0/37 (0%)) (RR 6.19, 95% CI 0.31 to 122.05; 2 trials with 69 patients; I² = 0%). Bezafibrate significantly decreased the activity of serum alkaline phosphatases compared with no intervention (MD -186.04 U/L, 95% CI -249.03 to -123.04; 4 trials with 79 patients; I² = 34%) and when compared with UDCA (MD -162.90 U/L, 95% CI -199.68 to -126.12; 2 trials with 48 patients; I² = 0%). These results were supported by trial sequential analyses. Bezafibrate compared with no intervention significantly decreased plasma immunoglobulin M (MD -164.00 mg/dl, 95% CI -259.47 to -68.53; 3 trials with 50 patients; I² = 46%) and serum bilirubin concentration (MD -0.19 mg/dl, 95% CI -0.38 to -0.00; 2 trials with 34 patients; I² = 0%). However, the latter two results were not supported by trial sequential analyses. Bezafibrate compared with no intervention had no significant effect on the activity of serum gamma-glutamyltransferase (MD -1.22 U/L, 95% CI -11.97 to 9.52; 4 trials with 79 patients; I² = 42%) and serum alanine aminotransferase (MD -5.61 U/L, 95% CI -24.50 to 13.27; 2 trials with 35 patients; I² = 34%). Bezafibrate compared with UDCA had no significant effect on the activity of serum gamma-glutamyltransferase (MD 38.44 U/L, 95% CI -180.67 to 257.55; 2 trials with 49 patients; I² = 89%), serum alanine aminotransferase (MD -2.34 U/L, 95% CI -34.73 to 30.06; 2 trials with 49 patients; I² = 95%), and plasma immunoglobulin M concentration (MD -20.23 mg/dl, 95% CI -218.71 to 178.25; 2 trials with 41 patients; I² = 90%) in random-effects model meta-analyses, but bezafibrate significantly decreased the activity of serum gamma-glutamyltransferase (MD -58.18, 95% CI -76.49 to -39.88; 2 trials with 49 patients; I² = 89%), serum alanine aminotransferase (MD -13.94, 95% CI -18.78 to -9.09; 2 trials with 49 patients; I² = 95%), and plasma immunoglobulin M concentration (MD -99.90, 95% CI -130.72 to -69.07; 2 trials with 41 patients; I² = 90%) in fixed-effect model meta-analyses. One patient had bezafibrate withdrawn due to an adverse event compared to no intervention (RD 0.03, 95% CI -0.09 to 0.16; 2 trials with 60 patients; I² = 0%).

AUTHORS' CONCLUSIONS

This systematic review did not demonstrate any effect of bezafibrate versus no intervention on mortality, liver-related morbidity, adverse events, and pruritus in patients with primary biliary cirrhosis. Furthermore, we found no significant effects of bezafibrate on mortality, liver-related morbidity, or adverse events when compared with ursodeoxycholic acid, None of the trials assessed quality of life or fatigue. The data seem to indicate a possible positive intervention effect of bezafibrate on some liver biochemistry measures compared with the control group, but the observed effects could be due to systematic errors or random errors. We need more randomised clinical trials on the effects of bezafibrate on primary biliary cirrhosis with low risks of systematic errors and random errors.

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic autoimmune inflammatory disease of the liver with a striking female preponderance. It has an insidious onset and typically affects middle-aged women. The disease manifests gradually with symptoms of fatigue, pruritis, and increased alkaline phosphatase levels on laboratory evaluation. The hallmark of the disease is the circulating antimitochondrial antibody. Histology is characterized by inflammation of the bile ducts, destruction of cholangiocytes, and subsequent cholestasis, progressing to biliary cirrhosis. The standard treatment for primary biliary cirrhosis is ursodeoxycholic acid, which improves survival, but the disease can still lead to cirrhosis and liver failure over decades.

Regulation of endobiotics glucuronidation by ligand-activated transcription factors: physiological function and therapeutic potential

Recent progresses in molecular pharmacology approaches have allowed the identification and characterization of a series of nuclear receptors (NR) which efficiently control the level UDP-glucuronosyltransferase (UGT) genes expression. These regulatory processes ensure optimized UGT expression in response to specific endogenous and/or exogenous stimuli. Interestingly, numerous endogenous activators of these NRs are conjugated by the UGT enzymes they regulate. In such a case, the NR-dependent regulation of UGT genes corresponds to a feedforward/feedback mechanism by which a bioactive molecule controls its own concentrations. In the present review, we will discuss i) how bilirubin reduces its circulating levels by activating AhR in the liver; ii) how bile acids modulate their hepatic glucuronidation via PXR- and FXR-dependent processes in enterohepatic tissues; and iii) how androgens inhibit their cellular metabolism in prostate cancer cells through an AR-dependent mechanism. Subsequently, with further discussion of the same examples (bilirubin and bile acids), we will illustrate how NR-dependent regulation of UGT enzymes may contribute to the beneficial effects of pharmacological activators of nuclear receptors, such as CAR and PPARa.

Bezafibrate treatment of primary biliary cirrhosis following incomplete response to ursodeoxycholic acid

BACKGROUND AND GOALS

Ursodeoxycholic acid (UDCA) is the only current pharmacologic treatment for primary biliary cirrhosis (PBC). However, some patients show persistent liver biochemical abnormalities even after 6 to 12 months treatment. Bezafibrate retard is a commonly used medication for hyperlipidemia. In Japanese studies, it was found to lower liver enzyme levels, apparently through its action on multiple drug resistance gene 3, a transport element of the ATP-dependent bile secretion system, and on peroxisome proliferator-activated receptor-alpha. The aim of this study was to evaluate the effect of adding bezafibrate to the treatment regimen in patients with PBC and a partial response to UDCA.

STUDY

The study group included 8 White patients, 7 women and 1 man, aged 52 to 76 years with PBC who had been treated at our Liver Institute with UDCA (900 mg/d to 1500 mg/d) for 2 to 11 years (mean, 5.7 y) with only a partial response (19% to 56% reduction in alkaline phosphatase level). Bezafibrate (400 mg/d) was added to UDCA and the patients were followed for 4 to 12 months.

RESULTS

Alkaline phosphatase levels (normal range, 35 to 104 U/L) decreased in all patients, from 140 to 360 U/L (mean, 201.2) to 68 to 158 U/L (mean, 98.4), and normalized in 6 patients. In addition, levels of gamma-glutamyl transferase (normal range, 6 to 42 U/L) decreased from 70 to 192 U/L (mean, 130) to 41 to 122 U/L (mean, 71.8). These findings were maintained throughout follow-up.

CONCLUSIONS

Combination therapy with bezafibrate and UDCA improves the biochemical profile of patients with PBC who respond only partially to UDCA. A larger controlled study is needed to evaluate the clinical implications of these findings.

Fenofibrate in primary biliary cirrhosis: a pilot study

Background:

Most patients with primary biliary cirrhosis (PBC) are treated with ursodeoxycholic acid (UDCA); however, some do not respond fully. PBC is also associated with dyslipidemia, but a link with vascular risk has not been confirmed.

Methods and Results:

In this study we compared UDCA monotherapy with fenofibrate plus UDCA in PBC patients with incomplete biochemical response to UDCA monotherapy for ≥ 8 months. Ten patients (57.2±13.3 years old) with PBC and persistent elevations of liver enzymes after treatment with UDCA (600 mg/day) were randomized to continue UDCA (4 patients) or to receive micronized fenofibrate (200 mg/day) plus UDCA (6 patients) for 8 weeks. Significant reductions in total cholesterol, triglycerides and non-high density lipoprotein cholesterol were observed in the combination treatment group. The serum activities of alkaline phosphatase, gamma-glutamyl transpeptidase and alanine aminotranferase also decreased in this group compared with baseline (-32.6%; p=0.012, -44%; p=0.031 and -16.9%; p=0.029, respectively). In contrast, no significant alterations in liver enzymes or lipid profile were observed in patients who continued UDCA monotherapy. The changes in the lipid and enzyme variables differed significantly (p<0.03) between the 2 groups. Fenofibrate was well tolerated.

Conclusions:

The administration of fenofibrate plus UDCA seems to be safe and may improve lipid and liver indices in patients with PBC who do not respond fully to UDCA monotherapy. Whether the improved lipid profile translates into a decreased risk of vascular events remains to be established.

Nuclear receptors as drug targets in cholestasis and drug-induced hepatotoxicity

Nuclear receptors are key regulators of various processes including reproduction, development, and metabolism of xeno- and endobiotics such as bile acids and drugs. Research in the last two decades provided researchers and clinicians with a detailed understanding of the regulation of these processes and, most importantly, also prompted the development of novel drugs specifically targeting nuclear receptors for the treatment of a variety of diseases. Some nuclear receptor agonists are already used in daily clinical practice but many more are currently designed or tested for the treatment of diabetes, dyslipidemia, fatty liver disease, cancer, drug hepatotoxicity and cholestasis. The hydrophilic bile acid ursodeoxycholic acid is currently the only available drug to treat cholestasis but its efficacy is limited. Therefore, development of novel treatments represents a major goal for both pharmaceutical industry and academic researchers. Targeting nuclear receptors in cholestasis is an intriguing approach since these receptors are critically involved in regulation of bile acid homeostasis. This review will discuss the general role of nuclear receptors in regulation of transporters and other enzymes maintaining bile acid homeostasis and will review the role of individual receptors as therapeutic targets. In addition, the central role of nuclear receptors and other transcription factors such as the aryl hydrocarbon receptor (AhR) and the nuclear factor-E2-related factor (Nrf2) in mediating drug disposition and their potential therapeutic role in drug-induced liver disease will be covered.

Liver disease associated with canalicular transport defects: current and future therapies

Bile formation at the canalicular membrane is a delicate process. This is illustrated by inherited liver diseases due to mutations in ATP8B1, ABCB11, ABCB4, ABCC2 and ABCG5/8, all encoding hepatocanalicular transporters. Effective treatment of these canalicular transport defects is a clinical and scientific challenge that is still ongoing. Current evidence indicates that ursodeoxycholic acid (UDCA) can be effective in selected patients with PFIC3 (ABCB4 deficiency), while rifampicin reduces pruritus in patients with PFIC1 (ATP8B1 deficiency) and PFIC2 (ABCB11 deficiency), and might abort cholestatic episodes in BRIC (mild ATP8B1 or ABCB11 deficiency). Cholestyramine is essential in the treatment of sitosterolemia (ABCG5/8 deficiency). Most patients with PFIC1 and PFIC2 will benefit from partial biliary drainage. Nevertheless liver transplantation is needed in a substantial proportion of these patients, as it is in PFIC3 patients. New developments in the treatment of canalicular transport defects by using nuclear receptors as a target, enhancing the expression of the mutated transporter protein by employing chaperones, or by mutation specific therapy show substantial promise. This review will focus on the therapy that is currently available as well as on those developments that are likely to influence clinical practice in the near future.

Nuclear receptors as therapeutic targets in cholestatic liver diseases

Cholestasis results in intrahepatic accumulation of cytotoxic bile acids, which cause liver damage ultimately leading to biliary fibrosis and cirrhosis. Cholestatic liver injury is counteracted by a variety of adaptive hepatoprotective mechanisms including alterations in bile acid transport, synthesis and detoxification. The underlying molecular mechanisms are mediated mainly at a transcriptional level via a complex network involving nuclear receptors including the farnesoid X receptor, pregnane X receptor, vitamin D receptor and constitutive androstane receptor, which target overlapping, although not identical, sets of genes. Because the intrinsic adaptive response to bile acids cannot fully prevent liver injury in cholestasis, therapeutic targeting of these receptors via specific and potent agonists may further enhance the hepatic defence against toxic bile acids. Activation of these receptors results in repression of bile acid synthesis, induction of phases I and II bile acid hydroxylation and conjugation and stimulation of alternative bile acid export while limiting hepatocellular bile acid import. Furthermore, the use of nuclear receptor ligands may not only influence bile acid transport and metabolism but may also directly target hepatic fibrogenesis and inflammation. Many drugs already used to treat cholestasis and its complications such as pruritus (e.g. ursodeoxycholic acid, rifampicin, fibrates) may act via activation of nuclear receptors. More specific and potent nuclear receptor ligands are currently being developed. This article will review the current knowledge on nuclear receptors and their potential role in the treatment of cholestatic liver diseases.

Effects of bezafibrate on dyslipidemia with cholestasis in children with familial intrahepatic cholestasis-1 deficiency manifesting progressive familial intrahepatic cholestasis

No appropriate pharmaceutical therapy has been established for dyslipidemia with cholestasis in progressive familial intrahepatic cholestasis (PFIC)-1. We evaluated the efficacy of bezafibrate in PFIC-1. We monitored the clinical presentation and lipoprotein metabolism of 3 patients, aged 3, 4, and 8 years, with FIC1 deficiency, manifesting PFIC-1, over 12 months of bezafibrate therapy. Pruritus was substantially alleviated in the 3 patients after initiation of bezafibrate. Cholestasis was alleviated in 2 of them. Serum high-density lipoprotein cholesterol and low-density lipoprotein cholesterol increased 1.6- to 2.0-fold and 1.1- to 1.2-fold, respectively; but the values remained low and normal, respectively. Serum lipoprotein X, which was at normal levels before treatment, was elevated to levels above the upper limit of the reference range. High serum triglyceride levels decreased by 15% to 30%, to normal levels, after treatment initiation. The activities of lipoprotein lipase and hepatic triglyceride lipase were increased, but those of high-density lipoprotein regulators remained unchanged. Liver expression of multidrug resistance protein-3, which regulates lipoprotein X synthesis, was enhanced by bezafibrate therapy. Bezafibrate treatment favorably affected pruritus, dyslipidemia, and cholestasis in PFIC-1.

Cholesterol-lowering effect of bezafibrate is independent of peroxisome proliferator-activated receptor activation in mice

The hypocholesterolemic potential of peroxisome proliferator-activated receptor (PPAR) pan-activator bezafibrate has been documented. However, in addition to uncertainty about the contribution of PPAR alpha to its effect, there is a marked discrepancy in bezafibrate dosages used in previous rodent experiments (> or = 50 mg/kg/day) and those in clinical use (< or = 10 mg/kg/day). To investigate the association between bezafibrate-induced cholesterol reduction and PPAR alpha activation, wild-type and Ppar a-null mice were treated with bezafibrate at high (100 mg/kg/day) or low (10 mg/kg/day) doses and analyzed. High-dose treatment decreased hepatic cholesterol content in wild-type mice, but increased serum cholesterol concentration. In liver samples, simultaneous increases in the expression of numerous proteins involved in cholesterol biosynthesis and catabolism, as well as cholesterol influx and efflux, were observed, which made interpretation of phenotype changes subtle. These complicated responses were believed to be associated with intensive PPAR activation and accompanying up-regulation of liver X receptor alpha, farnesoid X receptor, and sterol regulatory element-binding protein 2 (SREBP2). In contrast, low-dose bezafibrate treatment decreased serum and hepatic cholesterol concentrations in a PPAR alpha-independent manner, probably from suppression of SREBP2-regulated cholesterogenesis and enhancement of cholesterol catabolism due to elevated 7alpha-hydroxylase levels. Interestingly, the low-dose treatment did not affect the expression of PPAR target genes or number of peroxisomes, suggesting the absence of PPAR activation. These results demonstrate that the action of bezafibrate on cholesterol metabolism may vary with dosage, and that the cholesterol-reducing effect found in mice at dosages similar to those administered to humans is independent of significant PPAR activation.

Clinical epidemiology of primary biliary cirrhosis: incidence, prevalence, and impact of therapy

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown etiology. It is typically characterized by a trio of criteria including cholestatic liver biochemistry tests for at least 6 month's duration, the presence of a positive serum antimitochondrial antibody, and histologic findings from liver biopsy that are compatible or diagnostic with PBC. Although no unifying mechanism of action has been described to explain the pathogenesis of PBC to date, the natural history of this condition is greatly influenced by several known and unknown risk factors. In turn, a number of publications have focused on describing the burden of disease and prognosis in patients with PBC, This review article will summarize the descriptive epidemiology of PBC including new insights on risk factors, prognosis, and the effect of medical therapy in contemporary patients.

Primary biliary cirrhosis, hyperlipidemia, and atherosclerotic risk: a systematic review

Primary Biliary Cirrhosis (PBC) is a chronic, progressive liver disease associated with markedly elevated serum lipids, but it is not clear if PBC is associated with accelerated atherosclerosis. The present systematic review examined the relationship of PBC to atherosclerotic risk. The lipid abnormalities in PBC are complex, depend on the stage of hepatic dysfunction and affect most lipoprotein classes. Increased cholesterol levels in PBC are primarily due to LP-X, an abnormal LDL particle. LP-X has anti-atherogenic properties and may reduce the atherosclerotic risk. Few studies have examined coronary artery disease (CAD) events in PBC, and none have sufficient sample size of follow-up to determine CAD risk in PBC patients. Nevertheless, one study suggested that 12% of PBC patients died from circulatory system diseases suggesting that lipid treatment is appropriate in some patients. Additional larger scale, prospective studies are required to determine the necessity of lipid treatment in this patient group. In the interim, decisions on the use of lipid lowering agents depend largely on the prognosis of the PBC and physician and patient preference for treatment.

Role of nuclear receptors in the adaptive response to bile acids and cholestasis: pathogenetic and therapeutic considerations

Cholestasis results in intrahepatic accumulation of cytotoxic bile acids which cause liver injury ultimately leading to biliary fibrosis and cirrhosis. Cholestatic liver damage is counteracted by a variety of intrinsic hepatoprotective mechanisms. Such defense mechanisms include repression of hepatic bile acid uptake and de novo bile acid synthesis. Furthermore, phase I and II bile acid detoxification is induced rendering bile acids more hydrophilic. In addition to "orthograde" export via canalicular export systems, these compounds are also excreted via basolateral "alternative" export systems into the systemic circulation followed by renal elimination. Passive glomerular filtration of hydrophilic bile acids, active renal tubular secretion, and repression of tubular bile acid reabsorption facilitate renal bile acid elimination during cholestasis. The underlying molecular mechanisms are mediated mainly at a transcriptional level via a complex network involving nuclear receptors and other transcription factors. So far, the farnesoid X receptor FXR, pregnane X receptor PXR, and vitamin D receptor VDR have been identified as nuclear receptors for bile acids. However, the intrinsic adaptive response to bile acids cannot fully prevent liver injury in cholestasis. Therefore, additional therapeutic strategies such as targeted activation of nuclear receptors are needed to enhance the hepatic defense against toxic bile acids.

Molecular regulation of hepatobiliary transport systems: clinical implications for understanding and treating cholestasis

Hepatobiliary transport systems are responsible for hepatic uptake and excretion of bile salts and other biliary constituents (eg, bilirubin) into bile. Hereditary transport defects can result in progressive familial and benign recurrent intrahepatic cholestasis. Exposure to acquired cholestatic injury (eg, drugs, hormones, proinflammatory cytokines, biliary obstruction or destruction) also results in altered expression and function of hepatic uptake and excretory systems, changes that may maintain and contribute to cholestasis and jaundice. Recruitment of alternative efflux pumps and induction of phase I and II detoxifying enzymes may limit hepatic accumulation of potentially toxic biliary constituents in cholestasis by providing alternative metabolic and escape routes. These molecular changes are mediated by bile salts, proinflammatory cytokines, drugs, and hormones at a transcriptional and posttranscriptional level. Alterations of hepatobiliary transporters and enzymes are not only relevant for a better understanding of the pathophysiology of cholestatic liver diseases, but may also represent important targets for pharmacotherapy. Drugs (eg, ursodeoxycholic acid, rifampicin) used to treat cholestatic liver diseases and pruritus may counteract cholestasis via stimulation of defective transporter expression and function. In addition, therapeutic strategies may be aimed at supporting and stimulating alternative detoxification pathways and elimination routes for bile salts in cholestasis.

A nuclear receptor-mediated choleretic action of fibrates is associated with enhanced canalicular membrane fluidity and transporter activity mediating bile acid-independent bile secretion

Fibrates are commonly used lipid-lowering agents that act via PPARalpha, a member of the nuclear hormone receptor superfamily. The mechanism(s) of fibrate-induced changes in the hepatic canalicular membrane and bile lipids are still unknown. Therefore, the aim of this study was to investigate the influence of fibrates on hepatic lipid metabolism and to assess the hepatocellular cytoprotective effect on hepatocyte canalicular membrane. Male ICR mice were fed standard chow with or without bezafibrate (100 mg/kg) for 6 days. The expression of canalicular membrane transporters (Mdr2 and Mrp2) was evaluated by RT-PCR and Western blotting. Canalicular membrane fluidity was also investigated. Canalicular membrane fluidity was markedly increased by fibrates. The expression of mdr 2 and mrp2 mRNA and protein showed a significant increase in fibrate-treated mice. These results suggested that fibrates improve liver function by enhancing bile secretion. The mechanism of the choleretic action of fibrate therapy might involve the enhancement of bile acid-independent bile secretion, since increased expression of Mdr2 and Mrp2 was found in fibrate-treated animals. These changes were very likely mediated by PPARalpha, and the increase of canalicular membrane fluidity may have been partly associated with enhancement of this transporter activity.

Management of osteoporosis, fat-soluble vitamin deficiencies, and hyperlipidemia in primary biliary cirrhosis

Osteoporosis is several times more common in patients with PBC compared with the general population. Maintaining adequate intake of calcium and vitamin D is important for prevention of bone loss. The use of bisphosphonates or vitamin K to improve bone mineral density in osteopenic patients seems promising and needs to be further evaluated. Patients with PBC may develop fat-soluble vitamin deficiencies, especially vitamins A and D; serum levels should be investigated in patients considered at risk with the aim of recommending appropriate replacement therapy. Finally, hyperlipidemia in PBC does not seem to be associated with an increased risk of atherogenesis. New therapies in this patient population are currently under investigation.

Cholestatic syndromes

Further insights into the cellular and molecular mechanisms underlying hepatobiliary transport function and its regulation now permit a better understanding of the pathogenesis and treatment options of cholestatic liver diseases. Identification of the molecular basis of hereditary cholestatic syndromes will result in an improved diagnosis and management of these conditions. New insights into the pathogenesis of extrahepatic manifestations of cholestasis (eg, pruritus) have facilitated new treatment strategies. Important new studies have been published about the pathogenesis, clinical features, diagnosis, and treatment of primary biliary cirrhosis, primary sclerosing cholangitis, cholestasis of pregnancy, total parenteral nutrition-induced cholestasis, drug-induced cholestasis, and viral cholestatic syndromes.

Treatment Options for Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are chronic cholestatic liver diseases that affect 0.5 to 40 per 100,000 and 1 to 6 per 100,000 Americans, respectively. Prompt recognition and management of the clinical manifestations of these diseases is essential for the patients' well-being and ultimate outcome. Ursodeoxycholic acid (UDCA), 13 to 15 mg/kg per day, is the standard therapy for PBC and should be offered to every patient. It has been shown to slow progression of the disease and prevent the need for liver transplantation, which is the last recourse for patients with end-stage disease. However, there is no effective therapy for PSC yet. Patients are managed symptomatically, with surgical or endoscopic interventions as needed in cases of significant biliary obstruction. Complications of chronic cholestasis are seen in both PBC and PSC, with pruritus and fatigue being the most common complaints. The first choice for the treatment of pruritus is still cholestyramine, starting at 4 g/d. The pathogenesis of fatigue is poorly understood in this population; unrecognized hypothyroidism should be excluded. The use of antidepressants is currently under evaluation, but there is no specific therapy for fatigue as of yet. For prevention of severe osteoporosis, we recommend supplementation with 800 IU vitamin D and 1500 mg calcium/d. In patients with PBC and established osteoporosis, the use of alendronate and vitamin K appears to cause an increase in bone mineral density. Further studies are necessary before either of these drugs is routinely recommended. Finally, fat-soluble vitamin deficiencies are noted with more advanced disease. We recommend that serum levels be checked in high-risk patients, and that vitamins are replaced as appropriate with water-soluble supplements. However, other causes of malabsorption must be ruled out, including pancreatic insufficiency and celiac sprue.