Preventive administration of UDCA after liver transplantation for primary biliary cirrhosis is associated with a lower risk of disease recurrence

Characteristics and Outcomes of Liver Transplantation for Primary Biliary Cholangitis in Young Patients: Analysis of the United Network for Organ Sharing Database

BACKGROUND

Primary biliary cholangitis (PBC) in younger patients has been suggested to require liver transplantation (LT) in early adulthood, but data is limited on its outcomes. We aimed to evaluate the characteristics and outcome of LT in young patients with PBC in comparison with older adults.

METHODS

The United Network for Organ Sharing database was analyzed for all patients with PBC who underwent LT between 2000 and 2012. Based on age at the time of LT, subjects were divided into 2 groups: young patients (≤40 y) and older adults (≥41 y). Baseline demographics, clinical parameters, and outcomes of LT were then compared between the 2 groups. Univariable and multivariable analyses were performed to assess the factors associated with outcomes of LT.

RESULTS

A total of 2084 patients with PBC were included in the analysis with 158 young patients. Compared with older adults, younger patients were more likely to be male (27.2% versus 15.4%) and nonwhite (43.7% versus 21.5%), but they were less likely to have obesity, diabetes, or hypertension (P < 0.05) and had a lower mortality (8.2% versus 15.1%) but higher retransplantation rate (14.6% versus 4.7%) (P < 0.001). On multivariable analysis, older age, dialysis or ventilator use, and lower albumin were associated with high post-LT mortality.

CONCLUSIONS

Compared with older adults, early-onset PBC in younger patients requiring LT had higher percentage of males and nonwhites and had a lower prevalence of metabolic comorbidities but higher retransplantation rates. Further studies are warranted to confirm these findings.

PBC-transplantation and disease recurrence

Despite near universal use of ursodeoxycholic acid (UDCA) several patients with PBC still progress to liver transplant (LT) or death. Pruritus and fatigue are the most common symptoms. Liver transplantation for pruritus is highly effective but fatigue will not disappear in the majority of the patients. In contrast to other liver diseases, portal hypertension may develop in pre-cirrhotic patients with PBC. Patients with PBC have an incidence rate of 3.4 hepatocellular carcinoma cases for every 1000 patient-years and risk factors are advanced stage of the disease and male sex. For the appropriate timing of LT the utility of prognostic models (bilirubin, Mayo risk score and MELD, in particular) and standard exception points in case of HCC are established. However, recent data from different part of the world demonstrated that PBC patients compared to patients with PSC have higher waiting-list mortality. Hyperlipidemia can be present in up to 80% of the patients but there is no evidence for an elevated cardiovascular risk, certainly not in relationship with LT. Patients transplanted for PBC suffer more frequently from acute cellular and also late cellular rejection. However, 5-year patient survival rates after LT of 80-85% is better than for most other indications. Recurrent PBC is reported in a range from 14% up to 42% after LT but in contrast to other autoimmune diseases graft loss due to recurrent disease is not a major issue. The type of immunosuppression after LT was found to be associated with the incidence of recurrence but since mediate-term impact on overall and graft survival is negligible, tacrolimus-based regimens remain standard at most centers. Observational studies suggest that long-term administration of UDCA following LT has a beneficial effect on recurrence of PBC. Therefore biomarkers after LT that may identify patients at risk for recurrence should be further explored to allows early medical intervention.

Novel and emerging therapies for cholestatic liver diseases

While bile acids are important for both digestion and signalling, hydrophobic bile acids can be harmful, especially when in high concentrations. Mechanisms for the protection of cholangiocytes against bile acid cytotoxicity include negative feedback loops via farnesoid X nuclear receptor (FXR) activation, the bicarbonate umbrella, cholehepatic shunting and anti-inflammatory signalling, among others. By altering or overwhelming these defence mechanisms, cholestatic diseases such as primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) can further progress to biliary cirrhosis, end-stage liver disease and death or liver transplantation. While PBC is currently treated with ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), many fail treatment, and we have yet to find an effective therapy for PSC. Novel therapies under evaluation target nuclear and surface receptors including FXR, transmembrane G-protein-coupled receptor 5 (TGR5), peroxisome proliferator-activated receptor (PPAR) and pregnane X receptor (PXR). Modulation of these receptors leads to altered bile composition, decreased cytotoxicity, decreased inflammation and improved metabolism. This review summarizes our current understanding of the role of bile acids in the pathophysiology of cholestatic liver diseases, presents the rationale for already approved medical therapies and discusses novel pharmacologic therapies under investigation.

The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelines

Primary biliary cholangitis (formerly known as primary biliary cirrhosis, PBC) is an autoimmune liver disease in which a cycle of immune mediated biliary epithelial cell injury, cholestasis and progressive fibrosis can culminate over time in an end-stage biliary cirrhosis. Both genetic and environmental influences are presumed relevant to disease initiation. PBC is most prevalent in women and those over the age of 50, but a spectrum of disease is recognised in adult patients globally; male sex, younger age at onset (<45) and advanced disease at presentation are baseline predictors of poorer outcome. As the disease is increasingly diagnosed through the combination of cholestatic serum liver tests and the presence of antimitochondrial antibodies, most presenting patients are not cirrhotic and the term cholangitis is more accurate. Disease course is frequently accompanied by symptoms that can be burdensome for patients, and management of patients with PBC must address, in a life-long manner, both disease progression and symptom burden. Licensed therapies include ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), alongside experimental new and re-purposed agents. Disease management focuses on initiation of UDCA for all patients and risk stratification based on baseline and on-treatment factors, including in particular the response to treatment. Those intolerant of treatment with UDCA or those with high-risk disease as evidenced by UDCA treatment failure (frequently reflected in trial and clinical practice as an alkaline phosphatase >1.67 × upper limit of normal and/or elevated bilirubin) should be considered for second-line therapy, of which OCA is the only currently licensed National Institute for Health and Care Excellence recommended agent. Follow-up of patients is life-long and must address treatment of the disease and management of associated symptoms.

Current Status of Liver Transplantation for Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune cholestatic liver disease diagnosed with elevated alkaline phosphatase in the presence of antimitochondrial antibody. With the introduction and widespread use of ursodeoxycholic acid the proportion of PBC patients undergoing liver transplant (LT) has decreased. However, up to 40% of patients are ursodeoxycholic acid nonresponders and require second-line treatment or progress to end-stage liver disease requiring LT. Several scoring systems have been developed and validated to assess treatment response and transplant-free survival in patients. Although PBC is a favorable indication for LT, recurrence of PBC may occur and requires biopsy for diagnosis.

Work in Progress: Drugs in Development

Primary biliary cholangitis is an archetypal autoimmune disease that causes cholestasis, fibrosis, and liver failure. Ursodeoxycholic acid and obeticholic acid are approved for its treatment. Not all patients respond, some are intolerant, many have ongoing symptoms, and new therapies are required. Herein we describe drugs in development and potential future biological targets. We consider compounds acting on the farnesoid X receptor/fibroblast growth factor 19 pathway, fibrates and other agonists of the peroxisome proliferator-activated receptor family, transmembrane-G-protein-receptor-5 agonists, and several immunological agents. We also consider the roles of bile acid reuptake inhibitors, nalfurafine, and fibrates in pruritus management.

The gastroenterologist's guide to management of the post-liver transplant patient

The management of the post-liver transplant patient is complex and involves a large interdisciplinary team. After referral to a transplant center, evaluation and listing, and eventual transplantation, the patient is cared for closely by the transplant center. Once deemed ready for discharge, the patient returns to the primary care provider for ongoing management of the various issues that increase in incidence post transplant such as osteoporosis, cardiovascular, and renal diseases, as well as metabolic syndrome. The role of the gastroenterologist is not well defined, but certainly, he or she may be called upon for the initial evaluation and ongoing management of gastrointestinal as well as hepatobiliary issues. This includes but is not limited to the investigation of abnormal liver tests, non-specific gastrointestinal complaints such as nausea, vomiting, or diarrhea, biliary complications, and even recurrent hepatic disease. Having familiarity with post-transplant immunosuppressive agents, drug interactions, and potential infectious and malignancy-related complications of transplant is essential, as the primary gastroenterologist may be expected in some situations to field the initial work-up, if patient access to the transplant center is limited. The aim of this review is to summarize the gastroenterologist's role in the management of the post-liver transplant patient.

Complications, symptoms, quality of life and pregnancy in cholestatic liver disease

Cholestatic liver diseases (CLDs) encompass a variety of disorders of bile formation and/or flow which generally result in progressive hepatobiliary injury and ultimately end-stage liver disease. Many patients with CLD are diagnosed between the ages of 20-50 years, a particularly productive period of life professionally, biologically and in other respects; it is not surprising, thus, that CLD is often associated with impaired health-related quality of life (HRQOL) and uncertainty regarding implications for and outcomes of pregnancy. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are the most prominent CLDs, both having considerable morbidity and mortality and representing major indications for liver transplantation. These disorders, as a consequence of their complications (eg ascites, hepatic osteodystrophy), associated conditions (eg inflammatory bowel disease) and symptoms (eg pruritus and fatigue), can significantly impair an array of domains of HRQOL. Here we review these impactful clinical aspects of PSC and PBC as well as the topics of fertility and pregnancy.

Clinical analysis of liver transplantation in autoimmune liver diseases

BACKGROUND

Autoimmune liver diseases (ALDs) consist of autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), IgG4-associated cholangitis and overlap syndromes. Patients with these diseases may gradually progress to end-stage liver diseases and need liver transplantation. The present study aimed to explore the prognosis of patients with ALDs after liver transplantation.

METHODS

The clinical data of 80 patients with ALD (24 cases of AIH, 35 of PBC, 15 of PSC and 6 of AIH-PBC overlap syndromes) who underwent liver transplantation in Renji Hospital, Shanghai Jiao Tong University School of Medicine from June 2004 to September 2016 were collected retrospectively. The causes of death were analyzed and the postoperative cumulative survival rate was estimated by the Kaplan-Meier method. Recurrence and other complications were also analyzed.

RESULTS

Of the 80 patients, 18 were males and 62 were females. The average age was 50.5 years and the average Model for End-stage Liver Disease (MELD) score was 14.1. After a median follow-up of 19.8 months, 8 patients died. The 1-, 3- and 5-year cumulative survival rates were all 89.0%. Three cases of recurrent ALDs were diagnosed (3.8%) but they were not totally consistent with primary diseases. Biliary tract complication occurred in 10 patients (12.5%). The new onset of tumor was observed in 1 patient (1.3%). De novo HBV/CMV/EBV infection was found in 3, 8 and 3 patients, respectively.

CONCLUSION

Liver transplantation is an effective and safe treatment for end-stage ALD.

Regulatory T cells with a defect in inhibition on co-stimulation deteriorated primary biliary cholangitis

Regulatory T cells (Tregs) play an indispensable role in the progression of primary biliary cholangitis (PBC). Although Tregs could normalize costimulation in in vivo and in vitro models, it is obscure whether and how Tregs mediate these effects in PBC. Herein we focused on the quantitative and functional characteristics of Tregs in PBC. The number and proportion of Tregs, and the production of interleukin (IL)-10 were all significantly less in the PBC patients than in the healthy controls (HCs). In addition, compared to the HCs, the costimulatory CD86 of the circulation and liver were significantly higher in the patients with PBC. CD86 expression on CD1c+ cells negatively correlated with the proportion of Tregs. There was also a positive correlation between mayo risk score and the ratio of CD86/Treg. In vitro experiments showed that inhibition of CD86 expression on CD1c+ cells by Tregs was significantly weakened in the PBC patients. Furthermore, the autoantibodies from the PBC patients could promote CD86 expression on CD1c+ cells and transforming growth factor-β production by human hepatic stellate cells. Overall, Tregs declined in inhibition on co-stimulation expression in the presence of autoantibodies, which could be associated to PBC-related bile duct injury and fibrosis. This indicated that maintenance of balance of co-stimulation and Tregs could be beneficial for PBC.

Follow-up of the Post-Liver Transplantation Patient: A Primer for the Practicing Gastroenterologist

The focus in liver transplantation in the next 10 years will likely change from preventing viral disease recurrence to minimizing the toll of rejection and fatty liver disease, minimizing the complications from immunosuppression with withdrawal strategies, and more optimal management of long-term risks, such as malignancy, cardiovascular disease, and renal failure. In addition, now that short-term results (<1 year) have improved significantly, there will be a shift toward improving long-term patient and graft survival, as well as a focus on primary care preventive strategies.

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.

Cholestatic Liver Diseases After Liver Transplant

Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are the most common cholestatic liver diseases (CLD) in adults. Liver transplant (LT) is desirable for those who progress to end-stage liver disease. CLD have become an uncommon indication for LT. PSC and PBC accounted for 7.1% of all adult LT in 2015. CLD have the best post-LT outcomes compared with other indications for LT. Disease recurrence of PSC and PBC after LT is reported in up to 37% and 43% of LT recipients, respectively. Although recurrent PBC does not affect post-LT outcomes, recurrent PSC is associated with worse post-LT survival.

Recurrence of primary sclerosing cholangitis, primary biliary cholangitis and auto-immune hepatitis after liver transplantation

Liver transplantation is a well-accepted treatment for decompensated chronic liver disease due to primary sclerosing cholangitis (PSC), primary biliary cholangitis (PBC) and auto-immune hepatitis (AIH). Survival after liver transplantation is generally good with 1 and 5-year survival rates around 90% and 70-85%. After transplantation, however, these diseases recur in 8.6-27% (rPSC), 10.9-42.3% (rPBC) and 7-42% (rAIH), and this poses significant challenges in terms of management and graft outcome in these patients. In this review we discuss the incidence, clinical presentation, challenges in diagnosis, reported risk factors and impact on post-transplant outcomes of recurrence of PSC, PBC and AIH after liver transplantation. We also discuss some of the limitations of current investigations and formulate idea's for future research objectives.

Old and new treatments for primary biliary cholangitis

Primary biliary cholangitis (formerly primary biliary cirrhosis) is a rare progressive cholestatic liver disease, whose hallmark features include a persistently elevated alkaline phosphatase level, presence of anti-mitochondrial antibodies and characteristic histology. Since 1998, ursodeoxycholic acid (UDCA), a bile acid, has been the only available therapeutic agent. Primary biliary cholangitis is associated with the development of end-stage liver disease, increased morbidity and mortality. UDCA has been shown to improve serum biochemistries, histology and delay the need for liver transplantation. The clinical issue is that approximately 25%-40% of patients do not respond to this standard therapy. In recent years, many trials have investigated alternative and adjunctive treatments, leading to the recent approval of obeticholic acid, an analogue of chenodeoxycholic acid, which has shown significant and sustained reductions in alkaline phosphatase levels in combination with UDCA. Obeticholic acid has rapidly been embraced as a new agent to improve the biochemical profile in refractory patients, in addition to being approved for use as monotherapy in patients who cannot tolerate UDCA. There are several other studies and targets which are being investigated. This review is intended to highlight the benefits of UDCA, educate the reader on the newly available obeticholic acid, and to summarize the many ongoing trials and therapeutic targets being investigated in attempts to control and cure primary biliary cholangitis.

Primary Biliary Cholangitis: Disease Pathogenesis and Implications for Established and Novel Therapeutics

Primary Biliary Cholangitis is a progressive, autoimmune cholestatic liver disorder. Cholestasis with disease progression may lead to dyslipidemia, osteodystrophy and fat-soluble vitamin deficiency. Portal hypertension may develop prior to advanced stages of fibrosis. Untreated disease may lead to cirrhosis, hepatocellular cancer and need for orthotopic liver transplantation. Classically, diagnosis is made with elevation of alkaline phosphatase, demonstration of circulating antimitochondrial antibody, and if performed: asymmetric destruction/nonsupperative cholangitis of intralobular bile ducts on biopsy. Disease pathogenesis is complex and results from innate and adaptive (cell-mediated and humoral) responses that lead to inflammation of biliary duct epithelium. Ongoing damage is amplified and sustained through bile acid toxicity. Use of weight based (13-15mg/kg) ursodeoxycholic acid is well established in retarding disease progression and improving survival; however, is ineffective in achieving complete biochemical remission in many. Recently, a Farnesoid X Receptor agonist, obeticholic acid, has been approved for use. A number of ongoing clinical studies are underway to evaluate utility of fibric acid derivatives, biologics, antifibrotics, and stem cells as monotherapy or in combination with ursodeoxycholic acid for primary biliary cholangitis. The aim of this review is to discuss disease pathogenesis and highlight rationale/implications for both established and novel therapeutics.

Recent advances in the diagnosis and treatment of primary biliary cholangitis

Primary biliary cholangitis (PBC), formerly referred to as primary biliary cirrhosis, is an infrequent progressive intrahepatic cholestatic autoimmune illness that can evolve into hepatic fibrosis, hepatic cirrhosis, hepatic failure, and, in some cases, hepatocellular carcinoma. The disease itself is characterized by T-lymphocyte-mediated chronic non-suppurative destructive cholangitis and elevated serum levels of extremely specific anti-mitochondrial autoantibodies (AMAs). In this article, we will not only review epidemiology, risk factors, natural history, predictive scores, radiologic approaches (e.g., acoustic radiation force impulse imaging, vibration controlled transient elastography, and magnetic resonance elastography), clinical features, serological characteristics covering biochemical markers, immunoglobulins, infections markers, biomarkers, predictive fibrosis marker, specific antibodies (including AMAs such as AMA-M2), anti-nuclear autoantibodies [such as anti-multiple nuclear dot autoantibodies (anti-sp100, PML, NDP52, anti-sp140), anti-rim-like/membranous anti-nuclear autoantibodies (anti-gp210, anti-p62), anti-centromere autoantibodies, and some of the novel autoantibodies], histopathological characteristics of PBC, diagnostic advances, and anti-diastole of PBC. Furthermore, this review emphasizes the recent advances in research of PBC in terms of therapies, including ursodeoxycholic acid, budesonide, methotrexate, obeticholic acid, cyclosporine A, fibrates such as bezafibrate and fenofibrate, rituximab, mesenchymal stem cells transplant, and hepatic transplant. Currently, hepatic transplant remains the only optimal choice with acknowledged treatment efficiency for end-stage PBC patients.

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.