Pretreatment prediction of response to ursodeoxycholic acid in primary biliary cholangitis: development and validation of the UDCA Response Score

Sub-optimal therapy of patients with primary biliary cholangitis (PBC) in the real-life stetting of the German PBC cohort

Real-world data on the management of patients with primary biliary cholangitis (PBC) are so far scarce in Germany. Therefore, we aimed to establish a nationwide registry and describe the clinical characteristics and therapy of PBC patients.Three different cohorts defined as ursodeoxycholic acid (UDCA) responders, as inadequate responders according to Paris II criteria, and as newly diagnosed patients were prospectively recruited.This manuscript includes the baseline data of the project.In total, 33/77 (43%) contacted centres (58% of university hospitals, 38% of non-university hospitals, and 24% of private practices) recruited 515 patients including 204 UDCA responders, 221 inadequate responders to UDCA, and 90 newly diagnosed patients.All patients were treated with UDCA; however, a UDCA dosage below the recommended dosage of 13 mg/kg/d was observed in 38.5% of individuals after 12 months of treatment. UDCA dosages were lower in nonacademic compared to academic centres.Only 75/219 (38.5%) of inadequate responders to UDCA received a second-line therapy with obeticholic acid (OCA) and/or bezafibrate (BZF). OCA (13% vs. 4.5%) and BZF (14% vs. 6.5%) were significantly more often prescribed by academic vs. nonacademic centres.Pruritus (27% vs. 15.5%), fatigue (23% vs. 4.5%), and sicca syndrome (14% vs. 1%) were significantly more often reported by academic centres.The German PBC registry could be established, which indicates suboptimal therapy in a relevant proportion of patients and shows significant differences between academic and nonacademic centres. Results are fundamental to improving clinical management at different levels of care.

Development and Validation of a Scoring System to Predict Response to Obeticholic Acid in Primary Biliary Cholangitis

BACKGROUND & AIMS

Obeticholic acid (OCA) is the only licensed second-line therapy for primary biliary cholangitis (PBC). With novel therapeutics in advanced development, clinical tools are needed to tailor the treatment algorithm. We aimed to derive and externally validate the OCA response score (ORS) for predicting the response probability of individuals with PBC to OCA.

METHODS

We used data from the Italian RECAPITULATE (N = 441) and the IBER-PBC (N = 244) OCA real-world prospective cohorts to derive/validate a score including widely available variables obtained either pre-treatment (ORS) or also after 6 months of treatment (ORS+). Multivariable Cox regressions with backward selection were applied to obtain parsimonious predictive models. The predicted outcomes were biochemical response according to POISE (alkaline phosphatase [ALP]/upper limit of normal [ULN]<1.67 with a reduction of at least 15%, and normal bilirubin), or ALP/ULN<1.67, or normal range criteria (NR: normal ALP, alanine aminotransferase [ALT], and bilirubin) up to 24 months.

RESULTS

Depending on the response criteria, ORS included age, pruritus, cirrhosis, ALP/ULN, ALT/ULN, GGT/ULN, and bilirubin. ORS+ also included ALP/ULN and bilirubin after 6 months of OCA therapy. Internally validated c-statistics for ORS were 0.75, 0.78, and 0.72 for POISE, ALP/ULN<1.67, and NR response, which raised to 0.83, 0.88, and 0.81 with ORS+, respectively. The respective performances in validation were 0.70, 0.72, and 0.71 for ORS and 0.80, 0.84, and 0.78 for ORS+. Results were consistent across groups with mild/severe disease.

CONCLUSIONS

We developed and externally validated a scoring system capable to predict OCA response according to different criteria. This tool will enhance a stratified second-line therapy model to streamline standard care and trial delivery in PBC.

Alkaline phosphatase and liver fibrosis at diagnosis are associated with deep response to ursodeoxycholic acid in primary biliary cholangitis

OBJECTIVE

Primary biliary cholangitis is a chronic and progressive autoimmune liver disease, whose prognosis can be improved by normalizing alkaline phosphatase and bilirubin. While ursodeoxycholic acid (UDCA) is first line standard of care, approximately 40 % of patients exhibit incomplete response. We aimed to identify prognostic markers for deep response to UDCA therapy at presentation.

PATIENT AND METHODS

Data from the Brazilian Cholestasis Study Group cohort were analyzed retrospectively. Patients were assessed for deep response, defined as normal alkaline phosphatase and bilirubin, after 1 year of UDCA treatment. Additionally, the performance of the UDCA response score in predicting deep response was evaluated.

RESULTS

A total of 297 patients were analyzed, with 57.2 % achieving an adequate response according to the Toronto criteria, while 22.9 % reached deep response. Cirrhosis (OR 0.460; 95 % CI 0.225-0.942; p = 0.034) and elevated baseline alkaline phosphatase levels (OR 0.629; 95 % CI 0.513-0.770; p < 0.001) were associated with reduced odds of deep response. The UDCA response score exhibited moderate discrimination power (AUROC = 0.769) but lacked calibration.

CONCLUSIONS

Baseline ALP and liver fibrosis emerge as the most important prognostic factors to predict normalization of alkaline phosphatase and bilirubin after UDCA. The UDCA response score was inadequate for predicting deep response in the Brazilian PBC population.

Primary biliary cholangitis

Primary biliary cholangitis is a chronic, autoimmune, cholestatic disease that mainly affects women aged 40-70 years. Recent epidemiological studies have shown an increasing incidence worldwide despite geographical heterogeneity and a decrease in the female-to-male ratio of those the disease affects. Similar to other autoimmune diseases, primary biliary cholangitis occurs in genetically predisposed individuals upon exposure to environmental triggers, specifically xenobiotics, smoking, and the gut microbiome. Notably, the diversity of the intestinal microbiome is diminished in individuals with primary biliary cholangitis. The intricate interplay among immune cells, cytokines, chemokines, and biliary epithelial cells is postulated as the underlying pathogenic mechanism involved in the development and progression of primary biliary cholangitis, and extensive research has been dedicated to comprehending these complex interactions. Following the official approval of obeticholic acid as second-line treatment for patients with an incomplete response or intolerance to ursodeoxycholic acid, clinical trials have indicated that peroxisome proliferator activator receptor agonists are promising additional second-line drugs. Future dual or triple drug regimens might reach a new treatment goal of normalisation of alkaline phosphatase levels, rather than a decrease to less than 1·67 times the upper limit of normal levels, and potentially improve long-term outcomes. Improvement of health-related quality of life with better recognition and care of subjective symptoms, such as pruritus and fatigue, is also an important treatment goal. Promising clinical investigations are underway to alleviate these symptoms. Efforts to facilitate better access to medical care and dissemination of current knowledge should enable diagnosis at an earlier stage of primary biliary cholangitis and ensure access to treatments based on risk stratification for all patients.

The treatment of primary biliary cholangitis: from shadow to light

Primary biliary cholangitis (PBC) is a chronic autoimmune cholestatic disease characterized by the destruction of the small intrahepatic bile ducts, which can progress to liver cirrhosis. The gold standard in the treatment of PBC is ursodeoxycholic acid (UDCA), which is indicated in all patients with PBC because it improves not only biochemical parameters but also patients' survival. An important milestone in the identification of patients at risk is the assessment of biochemical response to UDCA. Patients who respond to treatment have a lower incidence of hepatic events and better prognosis than patients who do not. Several scoring systems can be used to assess the response and identify non-responders who will benefit from second-line treatment. Obeticholic acid (OCA) is currently the only approved second-line treatment for PBC, which is effective for non-responders to UDCA therapy or patients, who have not tolerated UDCA therapy. However, OCA is contraindicated in advanced liver cirrhosis and portal hypertension. Moreover, pruritus may be a limiting factor for the administration of OCA. Fibrates have shown promising data supporting their use in non-responders to UDCA because they improve the biochemical parameters and elastographic findings and have possible antipruritic effects. Therefore, the idea of a triple treatment seems interesting. Clinical research is focusing on several other groups of drugs: peroxisome proliferator-activated receptor (PPAR) δ- and α/δ agonists, non-steroidal farnesoid X receptor agonists, fibroblast growth factor 19 modulators, and inhibitors of nicotinamide adenine dinucleotide phosphate oxidase 1 and 4.

Prognostic scores in primary biliary cholangitis

Aim: Evaluating prognostic scores' utility in predicting ursodeoxycholic acid (UDCA) biochemical response (BR) and long-term liver-related complications in primary biliary cholangitis (PBC) patients. Patients & methods: This retrospective single-center study included 50 predominantly female PBC patients (median age: 56) on UDCA treatment. BR was defined by Paris II criteria. Liver-related complications during a median 76-month follow-up were assessed. APRI, ALBI, Mayo, GLOBE and UK-PBC scores were calculated. Results: 64% achieved BR, while 40% experienced liver-related complications. All scores showed good BR prediction (concordance statistics: 0.76-0.94) and excellent negative predictive values for 5-year liver complications (concordance statistics: 0.73-0.89). Conclusion: Implementing these scores in clinical practice is encouraged due to their effectiveness in predicting BR- and liver-related events.

A new and simple score to predict adequate and deep response to ursodeoxycholic acid in patients with primary biliary cholangitis: the ALP-A score

BACKGROUND

Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cholangitis (PBC), but a significant proportion of patients do not respond adequately, leading to increased risk of adverse outcomes. This study aims to develop a new and straightforward predictive score to identify PBC patients likely to achieve a complete response to UDCA.

METHODS

A logistic regression analysis was conducted using a derivation cohort of PBC patients to identify pre-treatment variables associated with response to UDCA. This analysis led to the development of the ALP-A score, calculated as: Age at diagnosis divided by (alkaline phosphatase at diagnosis/upper limit of normal). ALP-A score accuracy was evaluated using the area under the ROC curve, validated with a large external cohort from Brazil. Additionally, the correlation between the ALP-A score and the previously validated UDCA response score (URS) was assessed.

RESULTS

ALP-A score had good predictive power for adequate (AUC 0.794; 95% CI, 0.737-0.852) and deep (0.76; 95% CI, 0.69-0.83) UDCA response at 1 year of treatment. A cutoff score of 17 and 23 points was determined to be the optimal threshold for distinguishing adequate and deep responders, respectively, from non-responders. ALP-A score demonstrated a sensitivity of 73%, specificity of 71%, positive predictive value of 65%, negative predictive value of 78%, and overall accuracy of 72% for biochemical response. The URS displayed similar discriminative ability (AUC 0.798; 95% CI, 0.741-0.855).

CONCLUSION

ALP-A score performs comparably to URS but offers the great advantage of simplicity for routine clinical use. It serves as a valuable tool to identify PBC patients less likely to respond to UDCA treatment, facilitating early consideration of alternative therapeutic approaches.

Extrahepatic conditions of primary biliary cholangitis: A systematic review and meta-analysis of prevalence and risk

BACKGROUND AND AIM

Many studies reported the prevalence of extrahepatic conditions (EHC) of primary biliary cholangitis (PBC), but the great heterogeneity existed across different studies. Therefore, we conducted the systematic review and meta-analyses to determine EHC prevalence and association with PBC.

METHODS

We searched PUBMED and included observational, cross-sectional and case-controlled studies. A random or fixed effects model was used to estimate the pooled prevalence and odd ratio (OR) as appropriate.

RESULTS

Of 5370 identified publications, 129 publications with 133 studies met the inclusion criteria. Sjögren's syndrome had the highest prevalence (21.4 % vs. 3 % in non-PBC individuals), followed by Raynaud's syndrome (12.3 % vs. 1 %), rheumatoid arthritis-like arthritis (5 % vs. 3 %), systemic sclerosis (3.7 % vs. 0 %) and systemic lupus erythematosus (2 % vs. 0 %). The prevalence of overall thyroid diseases (11.3 %), autoimmune thyroid diseases (9.9 %), osteoporosis (21.1 %), celiac disease (1 %) and chronic bronchitis (4.6 %) was also increased among PBC patients.

CONCLUSION

This is the first exhaustive study on the old theme about EHC of PBC. Given increased prevalence of many EHCs in PBC patients, promptly recognizing these EHCs are of great importance for timely and precise diagnosis of PBC.

Hepatic progenitor cell-originated ductular reaction facilitates liver fibrosis through activation of hedgehog signaling

Background: It is poorly understood what cellular types participate in ductular reaction (DR) and whether DR facilitates recovery from injury or accelerates hepatic fibrosis. The aim of this study is to gain insights into the role of hepatic progenitor cell (HPC)-originated DR during fibrotic progression. Methods: DR in liver specimens of PBC, chronic HBV infection (CHB) or NAFLD, and four rodent fibrotic models by different pathogenic processes was evaluated. Gli1 expression was inhibited in rodent models or cell culture and organoid models by AAV-shGli1 or treating with GANT61. Results: Severity of liver fibrosis was positively correlated with DR extent in patients with PBC, CHB or NAFLD. HPCs were activated, expanded, differentiated into reactive cholangiocytes and constituted "HPC-originated DR", accompanying with exacerbated fibrosis in rodent models of HPC activation & proliferation (CCl4/2-AAF-treated), Μdr2-/- spontaneous PSC, BDL-cholestatic fibrosis or WD-fed/CCl4-treated NASH-fibrosis. Gli1 expression was significantly increased in enriched pathways in vivo and in vitro. Enhanced Gli1 expression was identified in KRT19+-reactive cholangiocytes. Suppressing Gli1 expression by administration of AAV-shGli1 or GANT61 ameliorated HPC-originated DR and fibrotic extent. KRT19 expression was reduced after GANT61 treatment in sodium butyrate-stimulated WB-F344 cells or organoids or in cells transduced with Gli1 knockdown lentiviral vectors. In contrast, KRT19 expression was elevated after transducing Gli1 overexpression lentiviral vectors in these cells. Conclusions: During various modes of chronic injury, Gli1 acted as an important mediator of HPC activation, expansion, differentiation into reactive cholangiocytes that formed DR, and subsequently provoked hepatic fibrogenesis.

Reasons why women are more likely to develop primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic autoimmune disease of biliary stasis in which immune factors cause the gradual destruction of small bile ducts, biliary stasis, and eventually the development of liver fibrosis, cirrhosis, and even liver failure. One of the main characteristics of PBC is that it primarily affects middle-aged women, but the precise cause is still unknown. This article analyzes the unique causes and mechanisms of the female predominance of PBC and summarizes the potential causes.The female domination of PBC is reported to be primarily caused by sex hormones, environmental circumstances, and epigenetic changes, each of which has a different subtle impact on patients' gender disparities.

MGAT5/TMEM163 variant is associated with prognosis in ursodeoxycholic acid-treated patients with primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC) is a chronic immune-mediated liver disease. Previous genome-wide meta-analysis has identified the association between variants in TMEM163 with PBC. Here we aimed to evaluate the association between variants near the reported risk loci of TMEM163 at 2q21.3 and prognosis of PBC patients.

METHODS

We performed a retrospective analysis of 347 PBC patients treated with ursodeoxycholic acid (UDCA) for at least 1 year. We collected clinical data at diagnosis and 1 year after UDCA treatment. SNPs within 200 kb upstream and downstream of the lead variant were genotyped and screened.

RESULTS

We identified that rs661899 near MGAT5 and TMEM163 showed the strongest association with prognosis in PBC patients. Patients carrying the rs661899 T allele tended to respond incompletely to UDCA treatment and had worse performances in laboratory values including aspartate aminotransferase (53.5 vs 32 vs 28.5 U/L, p = 0.001), alkaline phosphate (157.25 vs 125 vs 113 U/L, p = 0.001), albumin (41.5 vs 42.3 vs 43.7 g/L, p = 0.008) and bilirubin (19.2 vs 14.9 vs 12.85 μmol/L, p = 0.001). GLOBE scores (p = 4.8 × 10-5) and UK-PBC risk scores (p = 4.6 × 10-4) were strongly correlated with rs661899 genotype. Patients with TT genotype had a higher risk for adverse events compared with CC genotype (p = 0.039) during the 1-year follow-up. Results were also verified in an independent cohort.

CONCLUSIONS

PBC patients carrying the rs661899 T allele are associated with poor prognosis and adverse outcomes after 1-year UDCA therapy.

New Therapies on the Horizon for Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease that can progress to cirrhosis and hepatic failure if left untreated. Ursodeoxycholic acid (UDCA) was introduced as a first-line drug for PBC around 1990; it remarkably improved patient outcomes, leading to the nomenclature change of PBC in 2015, from primary biliary "cirrhosis" to primary biliary "cholangitis." Nevertheless, 20-30% of patients exhibit an incomplete response to UDCA, resulting in significantly worse outcomes compared to those with a complete response. Therefore, improving the long-term outcomes of patients with an incomplete response to UDCA has been recognized as an unmet need. In addition, patients with PBC often suffer from a variety of debilitating symptoms, such as pruritus, fatigue and sicca syndrome, which significantly impair their health-related quality of life. Thus, appropriate management of these symptoms is currently regarded as another unmet need for PBC treatment. In this review, several compounds and drugs under clinical trials that can potentially solve these unmet needs are comprehensively discussed, and future directions of treatment policy of PBC are proposed for significantly improving long-term outcome as well as health-related quality of life of patients.

Prognostic models and autoimmune liver diseases

Autoimmune liver diseases (AILDs) are complex diseases with unknown causes and immune-mediated pathophysiology. In primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH) disease modifying drugs are available which improve patient quality and quantity of life. In primary sclerosing cholangitis (PSC) no medical therapy is available and the only accepted treatment is liver transplantation (LT). PBC, PSC and AIH possess features that describe the archetype of patients within each disorder. On the other hand, the classical disorders are not homogeneous, and patients within each diagnosis may present with a range of clinical, biochemical, serological, and histological findings. Singularly, they are considered rare diseases, but together, they account for approximately 20% of LTs in Europe and USA. Management of these patients is complex, as AILDs are relatively uncommon in clinical practice with challenges in developing expertise, disease presentation can be sneaky, clinical phenotypes and disease course are heterogeneous. Prognostic models are key tools for clinicians to assess patients' risk and to provide personalized care to patients. Aim of this review is to discuss challenges of the management of AILDs and how the available prognostic models can help. We will discuss the prognostic models developed in AILDs, with a special focus on the prognostic models that can support the clinical management of patients with AILDs: in PBC models based on ursodeoxycholic acid (UDCA) response and markers of liver fibrosis; in PSC several markers including biochemistry, disease stage and radiological semiquantitative markers; and finally in AIH, markers of disease stage and disease activity.

Effectiveness of Fenofibrate in Treatment-Naive Patients With Primary Biliary Cholangitis: A Randomized Clinical Trial

INTRODUCTION

Primary biliary cholangitis (PBC) is a progressive autoimmune liver disease, and patients with inadequate response to ursodeoxycholic acid (UDCA) treatment show reduced long-term survival. Recent studies have shown that fenofibrate is an effective off-label therapy for PBC. However, prospective studies on biochemical response including the timing of fenofibrate administration are lacking. This study is aimed to evaluate the efficacy and safety of fenofibrate in UDCA treatment-naive patients with PBC.

METHODS

A total of 117 treatment-naive patients with PBC were recruited from the Xijing Hospital for a 12-month randomized, parallel, and open-label clinical trial. Study participants were assigned to receive either UDCA standard dose (UDCA-only group) or fenofibrate at a daily dose of 200 mg in addition to UDCA (UDCA-Fenofibrate group).

RESULTS

The primary outcome was biochemical response percentage in patients according to the Barcelona criterion at 12 months. In the UDCA-Fenofibrate group, 81.4% (69.9%-92.9%) of patients achieved the primary outcome and 64.3% (51.9%-76.8%) in the UDCA-only group achieved the primary outcome ( P = 0.048). There was no difference between the 2 groups in noninvasive measures of liver fibrosis and biochemical markers other than alkaline phosphatase at 12 months. Creatinine and transaminases levels in the UDCA-Fenofibrate group increased within the first month, then returned to normal, and remained stable thereafter until the end of the study, even in patients with cirrhosis.

DISCUSSION

In this randomized clinical trial in treatment-naive patients with PBC, the combination of fenofibrate and UDCA resulted in a significantly higher biochemical response rate. Fenofibrate seemed to be well-tolerated in patients.

Treatment response to ursodeoxycholic acid in primary biliary cholangitis: A systematic review and meta-analysis

BACKGROUND

Several ursodeoxycholic acid (UDCA) treatment response definitions have been introduced in primary biliary cholangitis (PBC). However, the lack of a gold standard results in heterogeneity in second-line treatment research and clinical practice.

AIMS

This study aimed to explore which UDCA treatment response endpoint serves as the most accurate predictive model of long-term outcome.

METHODS

A systematic review and meta-analysis of UDCA treatment response endpoints (and corresponding validations) were performed.

RESULTS

Sixteen individual UDCA treatment response endpoints and 96 external validations were found. Barcelona, Paris-1, Paris-2, Rotterdam, Toronto and GLOBE and UK-PBC Risk Scores are currently most robustly validated in external populations. The results show that the continuous models (GLOBE and UK-PBC Risk Scores) serve as the most accurate predictive models. Besides standard UDCA treatment response endpoints, the alkaline phosphatase and total bilirubin normalization has been suggested as a new therapeutic target.

CONCLUSIONS

The GLOBE and UK-PBC Risk Scores are the most suitable for the real-world allocation of second-line therapies (obeticholic acid and fibrates). However, in the wake of the recent findings, alkaline phosphatase and total bilirubin normalization should be the primary outcome in trial research in PBC.

Determinants of the effectiveness of bezafibrate combined with ursodeoxycholic acid in patients with primary biliary cholangitis

BACKGROUND AND AIMS

For patients with primary biliary cholangitis (PBC) exhibiting suboptimal responses to ursodeoxycholic acid (UDCA), obeticholic acid (OCA), and bezafibrate (BZF) are currently used and shown to improve long-term outcomes. Nevertheless, we encounter patients who die or undergo liver transplantation (LT) even with combination treatment. In this study, we explored prognostic indicators in patients receiving combination treatment of UDCA and BZF.

METHODS

We took advantage of the Japanese PBC registry and enrolled patients who received both UDCA and BZF therapy in 2000 or later. The covariates investigated included baseline covariates as well as treatment covariates. Two main outcomes (all-cause death or LT and liver-related death or LT) were assessed using multivariable-adjusted Cox proportional hazards models.

RESULTS

In total, 772 patients were included. The median follow-up was 7.1 years. Using the Cox regression model, bilirubin (hazard ratio [HR] 6.85, 95% confidence interval [CI] 1.73-27.1, p = 0.006), alkaline phosphatase (HR 5.46, 95% CI 1.32-22.6, p = 0.019), and histological stage (HR 4.87, 95% CI 1.16-20.5, p = 0.031) were found associated with LT-free survival. For survival free from liver disease-related death or LT, albumin (HR 7.72, 95% CI 1.48-40.4, p = 0.016) and bilirubin (HR 14.5, 95% CI 2.37-88.5, p = 0.004) were found significantly associated.

CONCLUSION

In patients with PBC receiving combination therapy, prognostic variables were similar to those in patients receiving UDCA monotherapy. These results indicate the importance of diagnosing patients with PBC at an earlier stage because of the reduced effectiveness of BZF at advanced stages.

Risk Stratification in Primary Biliary Cholangitis

Primary Biliary Cholangitis (PBC) is a chronic cholestatic liver disease with a heterogeneous presentation, symptomatology, disease progression, and response to therapy. The current risk stratification assessment, aimed at identifying patients with a higher risk of disease progression, encompasses an in-depth analysis of demographic data, clinical and laboratory findings, antibody profiles, and the evaluation of liver fibrosis using both invasive and noninvasive techniques. Treatment response scores after one year of therapy remain to date a major factor influencing the prognosis of PBC patients. While the initial therapeutic approach with ursodeoxycholic acid (UDCA) is universally applied, new second-line treatment options have recently emerged, with many others under investigation. Consequently, the prevailing one-size-fits-all approach is poised to be supplanted by tailored strategies, ensuring high-risk patients receive the most appropriate treatment regimen from diagnosis. This will require the development of a risk prediction model to assess, at the time of diagnosis, the course, outcome, and response to first and additional treatments of PBC patients. This manuscript provides a comprehensive overview of the current and emerging tools used for risk stratification in PBC and speculates on how these developments might shape the disease landscape in the near future.

Cell transplantation-based regenerative medicine in liver diseases

This review aims to evaluate the current preclinical state of liver bioengineering, the clinical context for liver cell therapies, the cell sources, the delivery routes, and the results of clinical trials for end-stage liver disease. Different clinical settings, such as inborn errors of metabolism, acute liver failure, chronic liver disease, liver cirrhosis, and acute-on-chronic liver failure, as well as multiple cellular sources were analyzed; namely, hepatocytes, hepatic progenitor cells, biliary tree stem/progenitor cells, mesenchymal stromal cells, and macrophages. The highly heterogeneous clinical scenario of liver disease and the availability of multiple cellular sources endowed with different biological properties make this a multidisciplinary translational research challenge. Data on each individual liver disease and more accurate endpoints are urgently needed, together with a characterization of the regenerative pathways leading to potential therapeutic benefit. Here, we critically review these topics and identify related research needs and perspectives in preclinical and clinical settings.

Excellent outcome in patients with primary biliary cholangitis in Northwest Italy followed up for up to 30 years

OBJECTIVE

Primary biliary cholangitis (PBC) is a rare chronic autoimmune cholangiopathy, characterized by a variable course and response to treatment. We aimed to describe long-term outcomes of PBC patients referred to three academic centres in Northwest Italy.

METHODS

This is an ambispective cohort study of PBC patients (retrospective component: diagnosis before 1 January 2019; prospective component: thereafter), including 302 patients: 101 (33%) followed up in Novara, 86 (28%) in Turin, 115 (38%) in Genoa. Clinical features at diagnosis, biochemical response to therapy and survival were analyzed.

RESULTS

Among the 302 patients (88% women, median age 55 years, median follow-up 75 months), alkaline phosphatase (ALP) levels significantly decreased during treatment with ursodeoxycholic acid (UDCA, P < 0.0001) and obeticholic acid (P < 0.0001). At multivariate analysis, ALP at diagnosis was predictive of 1-year biochemical response to UDCA [odds ratio 3.57, 95% confidence interval (CI) 1.4-9, P < 0.001]. Estimated median survival free of liver transplantation and hepatic complications was 30 years (95% CI 19-41). Bilirubin level at diagnosis was the only independent risk factor for the combined outcome of death, transplantation or hepatic decompensation (hazard ratio, 1.65, 95% CI 1.66-2.56, P = 0.02). Patients presenting with total bilirubin at diagnosis ≥0.6 times the upper normal limit (ULN) had a significantly lower 10-year survival compared to those with bilirubin <0.6 times ULN (63% vs. 97%, P < 0.0001).

CONCLUSION

In PBC, both short-term response to UDCA and long-term survival can be predicted by simple conventional biomarkers of disease severity, obtained at diagnosis.

Clinical Outcomes and Validation of Ursodeoxycholic Acid Response Scores in Patients with Korean Primary Biliary Cholangitis: A Multicenter Cohort Study

Background/Aims

The ursodeoxycholic acid (UDCA) response score (URS) was developed to identify poor responders to UDCA before treatment, in order to offer timely and proactive intervention. However, validation of the URS in Asian population is warranted.

Methods

A total of 173 Asian patients diagnosed with primary biliary cholangitis (PBC) between 2007 and 2016 at seven academic institutions in Korea who started UDCA treatment were analyzed to validate the performance of URS. UDCA response was defined as an alkaline phosphatase level less than 1.67 times the upper limit of normal after 1-year of UDCA treatment. In addition, prognostic performance of URS for liver-related events, defined as newly developed hepatic decompensation or hepatocellular carcinoma was evaluated.

Results

After 1 year of UDCA treatment, 133 patients (76.9%) achieved UDCA response. UDCA response rate was 98.7% for those with URS ≥1.41 (n=76) and 58.8% for those with URS <1.41 (n=97). The area under the receiver operating characteristic curve of URS in predicting UDCA response was 0.84 (95% confidence interval, 0.78 to 0.88). During a median follow-up of 6.5 years, liver-related events developed in 18 patients (10.4%). Among 117 patients with PBC stage I-III by histological evaluation, the 5-year liver-related event-free survival rate differed according to the URS; 100% for URS ≥1.41 and 86.5% for URS <1.41 (p=0.005).

Conclusions

URS demonstrated good performance in predicting a UDCA treatment response in Asian PBC patients. In addition, the risk of liver-related events differed according to the URS for the PBC stage. Thus, URS can be used to predict the response and clinical outcome in patients with PBC.

Optimizing therapy in primary biliary cholangitis: Alkaline phosphatase at six months identifies one-year non-responders and predicts survival

BACKGROUND AND AIMS

Patients with primary biliary cholangitis (PBC) and insufficient response to ursodeoxycholic acid (UDCA), currently assessed after 1 year, are candidates for second-line therapy. The aims of this study are to assess biochemical response pattern and determine the utility of alkaline phosphatase (ALP) at six months as a predictor of insufficient response.

METHODS

UDCA-treated patients in the GLOBAL PBC database with available liver biochemistries at one year were included. POISE criteria were used to assess response to treatment, defined as ALP <1.67 × upper limit of normal (ULN) and normal total bilirubin at one year. Various thresholds of ALP at six months were evaluated to predict insufficient response based on negative predictive value (NPV) and that with nearest to 90% NPV was selected.

RESULTS

For the study, 1362 patients were included, 1232 (90.5%) female, mean age of 54 years. The POISE criteria were met by 56.4% (n = 768) of patients at one year. The median ALP (IQR) of those who met POISE criteria compared to those who did not was 1.05 × ULN (0.82-1.33) vs. 2.37 × ULN (1.72-3.69) at six months (p < .001). Of 235 patients with serum ALP >1.9 × ULN at six months, 89% did not achieve POISE criteria (NPV) after one year of UDCA. Of those with insufficient response by POISE criteria at one year, 210 (67%) had an ALP >1.9 × ULN at six months and thus would have been identified early.

CONCLUSIONS

We can identify patients for second-line therapy at six months using an ALP threshold of 1.9 × ULN, given that approximately 90% of these patients are non-responders according to POISE criteria.

P4HA2 induces hepatic ductular reaction and biliary fibrosis in chronic cholestatic liver diseases

BACKGROUNDS

Prolyl-4-hydroxylases (P4Hs) are key enzymes in collagen synthesis. The P4HA subunit (P4HA1, P4HA2, and P4HA3) contains a substrate binding and catalyzation domain. We postulated that P4HA2 would play a key role in the cholangiocyte pathology of cholestatic liver diseases.

METHODS

We studied humans with primary biliary cholangitis (PBC) and Primary sclerosing cholangitis (PSC), P4HA2 -/- mice injured by DDC, and P4HA2 -/- /MDR2 -/- double knockout mice. A parallel study was performed in patients with PBC, PSC, and controls using immunohistochemistry and immunofluorescence. In the murine model, the level of ductular reaction and biliary fibrosis were monitored by histology, qPCR, immunohistochemistry, and Western blotting. Expression of Yes1 Associated Transcriptional Regulator (YAP) phosphorylation was measured in isolated mouse cholangiocytes. The mechanism of P4HA2 was explored in RBE and 293T cell lines by using qPCR, Western blot, immunofluorescence, and co-immunoprecipitation.

RESULTS

The hepatic expression level of P4HA2 was highly elevated in patients with PBC or PSC. Ductular reactive cholangiocytes predominantly expressed P4HA2. Cholestatic patients with more severe liver injury correlated with levels of P4HA2 in the liver. In P4HA2 -/- mice, there was a significantly reduced level of ductular reaction and fibrosis compared with controls in the DDC-induced chronic cholestasis. Decreased liver fibrosis and ductular reaction were observed in P4HA2 -/- /MDR2 -/- mice compared with MDR2 -/- mice. Cholangiocytes isolated from P4HA2 -/- /MDR2 -/- mice displayed a higher level of YAP phosphorylation, resulting in cholangiocytes proliferation inhibition. In vitro studies showed that P4HA2 promotes RBE cell proliferation by inducing SAV1 degradation, eventually resulting in the activation of YAP.

CONCLUSIONS

P4HA2 promotes hepatic ductular reaction and biliary fibrosis by regulating the SAV1-mediated Hippo signaling pathway. P4HA2 is a potential therapeutic target for PBC and PSC.

Primary biliary cholangitis: Epidemiology, prognosis, and treatment

Primary biliary cholangitis (PBC) is a chronic cholestatic autoimmune liver disease characterized by a destructive, small duct, and lymphocytic cholangitis, and marked by the presence of antimitochondrial antibodies. The incidence and prevalence of PBC vary widely in different regions and time periods, and although disproportionally more common among White non-Hispanic females, contemporary data show a higher prevalence in males and racial minorities than previously described. Outcomes largely depend on early recognition of the disease and prompt institution of treatment, which, in turn, are directly influenced by provider bias and socioeconomic factors. Ursodeoxycholic acid remains the initial treatment of choice for PBC, with obeticholic acid and fibrates (off-label therapy) reserved as add-on therapy for the management of inadequate responders or those with ursodeoxycholic acid intolerance. Novel and repurposed drugs are currently at different stages of clinical development not only for the treatment of PBC but also for its symptomatic management. Here, we summarize the most up-to-date data regarding the epidemiology, prognosis, and treatment of PBC, providing clinically useful information for its holistic management.

Machine learning prediction model for treatment responders in patients with primary biliary cholangitis

Background and Aim

Treatment response to ursodeoxycholic acid may predict the prognosis of patients with primary biliary cholangitis (PBC). Recent studies have suggested the benefits of using machine learning (ML) to forecast complex medical predictions. We aimed to predict treatment response in patients with PBC using ML and pretreatment data.

Methods

We conducted a single-center retrospective study and collected data from 194 patients with PBC who were followed up for at least 12 months after treatment initiation. Patient data were analyzed with five ML models, namely random forest, extreme gradient boosting (XGB), decision tree, naïve Bayes, or logistic regression, to predict treatment response using the Paris II criteria. The established models were assessed using an out-of-sample validation. The area under the curve (AUC) was used to evaluate the efficacy of each algorithm. Overall survival and liver-related deaths were analyzed using Kaplan-Meier analysis.

Results

Compared to logistic regression (AUC = 0.595, P = 0.0219, 0.031 models), ML analyses showed significantly high AUC in the random forest (AUC = 0.84) and XGB (AUC = 0.83) models; however, the AUC was not significantly high for decision tree (AUC = 0.633) or naïve Bayes (AUC = 0.584) models. Kaplan-Meier analysis showed significantly improved prognoses in patients predicted to achieve the Paris II criteria by XGB (log-rank = 0.005 and 0.007).

Conclusion

ML algorithms could improve treatment response prediction using pretreatment data, which could lead to better prognoses. In addition, the ML model using XGB could predict the prognosis of patients before treatment initiation.

The association between soluble CD163, disease severity, and ursodiol treatment in patients with primary biliary cholangitis

INTRODUCTION

The macrophage activation marker soluble (s)CD163 is associated with disease severity and prognosis in patients with primary biliary cholangitis (PBC). Ursodeoxycholic acid (UDCA) treatment attenuates fibrosis progression in PBC patients, but its effect on macrophage activation is unclear. We examined the effect of UDCA on macrophage activation, as determined by sCD163 levels.

METHODS

We included 2 cohorts of PBC patients; 1 cohort with prevalent PBC patients, and 1 cohort of incident PBC patients before start of UDCA treatment and with follow-up after 4 weeks and 6 months. We measured sCD163 and liver stiffness in both cohorts. Further, we measured sCD163 and TNF-α shedding in vitro in monocyte-derived macrophages after UDCA and lipopolysaccharide incubation.

RESULTS

We included 100 patients with prevalent PBC [93% women, median age 63 y (interquartile range: 51-70)] and 47 patients with incident PBC [77% women, median age 60 y (49-67)]. Prevalent PBC patients had a lower median sCD163 of 3.54 mg/L (2.77-4.72) than incident PBC patients with a median sCD163 of 4.33 mg/L (2.83-5.99) at inclusion. Patients with an incomplete response to UDCA and patients with cirrhosis had higher sCD163 than responders to UDCA and noncirrhosis patients. After 4 weeks and 6 months of UDCA treatment median sCD163 decreased by 4.6% and 9.0%, respectively. In in vitro experiments, UDCA attenuated shedding of TNF-α, but not sCD163, from monocyte-derived macrophages.

CONCLUSION

In PBC patients, sCD163 levels correlated with liver disease severity and treatment response to UDCA. Further, after 6 months of UDCA treatment, we observed a decrease in sCD163, which may be related to the treatment.

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.

Primary biliary cholangitis as a roadmap for the development of novel treatments for cholestatic liver diseases†

The discovery of nuclear receptors and transporters has contributed to the development of new drugs for the treatment of cholestatic liver diseases. Particular progress has been made in the development of second-line therapies for PBC. These new drugs can be separated into compounds primarily targeting cholestasis, molecules targeting fibrogenesis and molecules with immune-mediated action. Finally, drugs aimed at symptom relief (pruritus and fatigue) are also under investigation. Obeticholic acid is currently the only approved second-line therapy for PBC. Drugs in the late phase of clinical development include peroxisome proliferator-activated receptor agonists, norursodeoxycholic acid and NADPH oxidase 1/4 inhibitors.

Knockout of secretin ameliorates biliary and liver phenotypes during alcohol-induced hepatotoxicity

BACKGROUND

Alcohol-related liver disease (ALD) is characterized by ductular reaction (DR), liver inflammation, steatosis, fibrosis, and cirrhosis. The secretin (Sct)/secretin receptor (SR) axis (expressed only by cholangiocytes) regulates liver phenotypes in cholestasis. We evaluated the role of Sct signaling on ALD phenotypes.

METHODS

We used male wild-type and Sct^-/- mice fed a control diet (CD) or ethanol (EtOH) for 8 wk. Changes in liver phenotypes were measured in mice, female/male healthy controls, and patients with alcoholic cirrhosis. Since Cyp4a10 and Cyp4a11/22 regulate EtOH liver metabolism, we measured their expression in mouse/human liver. We evaluated: (i) the immunoreactivity of the lipogenesis enzyme elongation of very-long-chain fatty acids 1 (Elovl, mainly expressed by hepatocytes) in mouse/human liver sections by immunostaining; (ii) the expression of miR-125b (that is downregulated in cholestasis by Sct) in mouse liver by qPCR; and (iii) total bile acid (BA) levels in mouse liver by enzymatic assay, and the mRNA expression of genes regulating BA synthesis (cholesterol 7a-hydroxylase, Cyp27a1, 12a-hydroxylase, Cyp8b1, and oxysterol 7a-hydroxylase, Cyp7b11) and transport (bile salt export pump, Bsep, Na⁺-taurocholate cotransporting polypeptide, NTCP, and the organic solute transporter alpha (OSTa) in mouse liver by qPCR.

RESULTS

In EtOH-fed WT mice there was increased biliary and liver damage compared to control mice, but decreased miR-125b expression, phenotypes that were blunted in EtOH-fed Sct^-/- mice. The expression of Cyp4a10 increased in cholangiocytes and hepatocytes from EtOH-fed WT compared to control mice but decreased in EtOH-fed Sct^-/- mice. There was increased immunoreactivity of Cyp4a11/22 in patients with alcoholic cirrhosis compared to controls. The expression of miR-125b decreased in EtOH-fed WT mice but returned at normal values in EtOH-fed Sct^-/- mice. Elovl1 immunoreactivity increased in patients with alcoholic cirrhosis compared to controls. There was no difference in BA levels between WT mice fed CD or EtOH; BA levels decreased in EtOH-fed Sct^-/- compared to EtOH-fed WT mice. There was increased expression of Cyp27a1, Cyp8b1, Cyp7b1, Bsep, NTCP and Osta in total liver from EtOH-fed WT compared to control mice, which decreased in EtOH-fed Sct^-/- compared to EtOH-fed WT mice.

CONCLUSIONS

Targeting Sct/SR signaling may be important for modulating ALD phenotypes.

Artificial intelligence for precision medicine in autoimmune liver disease

Autoimmune liver diseases (AiLDs) are rare autoimmune conditions of the liver and the biliary tree with unknown etiology and limited treatment options. AiLDs are inherently characterized by a high degree of complexity, which poses great challenges in understanding their etiopathogenesis, developing novel biomarkers and risk-stratification tools, and, eventually, generating new drugs. Artificial intelligence (AI) is considered one of the best candidates to support researchers and clinicians in making sense of biological complexity. In this review, we offer a primer on AI and machine learning for clinicians, and discuss recent available literature on its applications in medicine and more specifically how it can help to tackle major unmet needs in AiLDs.

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.

Incomplete response to ursodeoxycholic acid in primary biliary cholangitis: criteria, epidemiology, and possible mechanisms

INTRODUCTION

As a common autoimmune disease with the characteristic of early complication, primary biliary cholangitis (PBC) leads to an increasing number of mortalities among people with end-stage liver disease (ESLD) waiting for liver transplantation. Ursodeoxycholic acid (UDCA) is the only approved first-line medicine for PBC, and a good response to treatment could acquire an ideal prognosis. Patients with poor UDCA response usually have more adverse outcomes and worse survival, therefore, the management of this group become a major consideration.

AREAS COVERED

Due to the complexity of race and environment for PBC, different criteria for UDCA response exhibit various predictive performances. Factors affecting UDCA response conditions include gender, age, ethnicity, serum indicators, auto-antibodies, and autoimmune comorbidities, while no agreement has been reached. In this review, we mainly focus on cellular senescence, immune-mediated damage, and vitamin D deficiency as possible mechanisms for UDCA non-responders.

EXPERT OPINION

The pathogenesis of PBC has yet to be clarified. Immunology-related mechanisms and therapy targets ought to be the main effort made for further study. Irrespective of the response condition, UDCA is recommended for routine administration in all PBC patients without contraindication. Ongoing clinical trials of second-line and additional therapy exhibit promising prospects.

Prognostic Scoring Systems in Primary Biliary Cholangitis: An Update

Primary biliary cholangitis (PBC) is a complex, chronic disease with a heterogeneous presentation, disease progression, and response to therapy. Several prognostic models based on disease stage and/or treatment response enhance risk stratification and therapeutic management. Recent work on disease modeling proposed early prediction of outcomes at PBC onset, yet this has not been implemented in clinical practice. Although early stratification of patients based on their individual risk of developing end-stage liver disease may prove cost-effective and actually become matter of medical deontology to timely offer the best therapeutic option, given the forthcoming availability of novel, disease-modifying drugs. This review outlines established and novel prognostic systems in PBC and provides some perspectives on the potential role of omics-derived biomarkers in developing reliable risk prediction models and promoting the implementation of personalized medicine in PBC.

Predictors of serious adverse events and non-response in cirrhotic patients with primary biliary cholangitis treated with obeticholic acid

BACKGROUND & AIMS

Obeticholic acid (OCA) has recently been restricted in patients with primary biliary cholangitis (PBC) with "advanced cirrhosis" because of its narrow therapeutic index. We aimed to better define the predicting factors of hepatic serious adverse events (SAEs) and non-response in cirrhotic patients undergoing OCA therapy.

METHODS

Safety and efficacy of treatment were evaluated in a cohort of consecutive PBC cirrhotic patients started with OCA. OCA response was evaluated according to the Poise criteria. Risk factors for hepatic SAEs and non-response were reported as risk ratios (RR) with 95% confidence intervals (CIs).

RESULTS

One hundred PBC cirrhotics were included, 97 Child-Pugh class A and 3 class B. Thirty-one had oesophageal varices and 5 had a history of ascites. Thirty-three per cent and 32% of patients achieved a biochemical response at 6 and 12 months respectively. Male sex (adjusted-RR 1.75, 95%CI 1.42-2.12), INR (1.37, 1.00-1.87), Child-Pugh score (1.79, 1.28-2.50), MELD (1.17, 1.04-1.30) and bilirubin (1.83, 1.11-3.01) were independently associated with non-response to OCA. Twenty-two patients discontinued OCA within 12 months: 10 for pruritus, 9 for hepatic SAEs (5 for jaundice and/or ascitic decompensation; 4 for upper digestive bleeding). INR (adjusted-RR 1.91, 95%CI 1.10-3.36), lower albumin levels (0.18, 0.06-0.51), Child-Pugh score (2.43, 1.50-4.04), history of ascites (3.5, 1.85-6.5) and bilirubin (1.30, 1.05-1.56), were associated with hepatic SAEs. A total bilirubin≥1.4 mg/dl at baseline was the most accurate biochemical predictor of hepatic SAEs under OCA.

CONCLUSIONS

An accurate baseline assessment is crucial to select cirrhotic patients who can benefit from OCA. Although OCA is effective in one third of cirrhotics, bilirubin level ≥1.4 mg/dl should discourage from its use.

Autoantibodies in Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic immune-mediated liver disease characterized by a lymphocytic cholangitis, with subsequent cholestasis, progressive liver fibrosis, and ultimately complications arising from end-stage liver disease. Testing for autoantibodies is important in the diagnosis of PBC, as well as stratifying prognosis. This review focuses on the role of autoantibodies in the diagnosis of PBC, as well as the relationship between autoantibodies with pathophysiology and prognostication, along with a discussion regarding novel and other related disease autoantibodies.

Primary biliary cholangitis: perception and expectation of illness

An important tool to explore personal experience of symptoms, treatment and clinical outcome is stratification of illness perception in patients affected by PBC.

AIM

To assess the perception of illness in a cohort of Italian patients with PBC.

METHODS

Between June and December 2019, a specific questionnaire was administered to a pool of 210 patients from 7 tertiary Italian centers, in order to identify and assess the patient's past history, symptoms and their impact on the quality of life, follow-up, treatment and perceived satisfaction of patients toward the provided care.

RESULTS

Fatigue, pruritus, and abdominal discomfort and sicca syndrome were present in 50.4%, 45%, 30.4% and 28.5% of patients, fatigue having the most impacting the daily-life. After a consultation with a specialist, the diagnosis of PBC was met within 18 months for 143 patients. Patients were mostly concerned about possible health problems that occur and in 25% of cases, symptoms had a negative impact on their life. Eighty percent of patients said they were satisfied with efficacy and tolerability of treatment, while 26% requested an improvement in the relationship with the specialist.

CONCLUSIONS

The results highlight the importance of both promoting timely referral to the specialist and facilitating communication between healthcare professionals and patients.

Characteristics and survival of patients with primary biliary cholangitis and hepatocellular carcinoma

BACKGROUND

Comprehensive and contemporary data pertaining large populations of patients with Primary Biliary Cholangitis (PBC) and hepatocellular carcinoma (HCC) are missing.

AIM

To describe main characteristics and outcome of PBC patients with HCC diagnosed in the new millennium.

METHODS

Analysing the Italian Liver Cancer registry we identified 80 PBC patients with HCC diagnosed after the year 2000, and described their clinical characteristics, access to treatment and survival.

RESULTS

Median age of patients was 71 years and 50.0% were males. Cirrhosis was present in 86.3% of patients, being well-compensated in 58.0%. Median HCC diameter was smaller in patients under surveillance (2.6 vs 4.0 cm, P = 0.007). Curative treatment, feasible in 50.0% of patients, was associated with improved survival compared to palliative and supportive care (42 vs 33 vs 6 months, P<0.0001). Surveillance was associated with a non-significant improved survival (36 vs 23 months), likely due to similar rate of curative treatment in patients under (51.4%) and outside surveillance (42.6%).

CONCLUSIONS

PBC patients with HCC are often elderly males with well-preserved liver function. Feasibility of curative treatment is high and associated with improved prognosis. Description of these patients may help focus surveillance to identify earlier tumours, increase their curability, and improve prognosis.

Role of ductular reaction and ductular-canalicular junctions in identifying severe primary biliary cholangitis

Background & Aims

Primary biliary cholangitis (PBC) is a chronic cholangiopathy characterised by immuno-mediated injury of interlobular bile ducts leading to intrahepatic cholestasis and progressive liver fibrosis. PBC histology is characterised by portal inflammation, progressive fibrosis, ductopenia, and the appearance of the so-called ductular reaction. The aim of the present study was to investigate the pathogenetic relevance of ductular reaction in PBC.

Methods

Liver biopsies were collected from naïve people with PBC (N = 87). Clinical-serological parameters were obtained at diagnosis and after 1 year of ursodeoxycholic acid (UDCA) treatment. Histological staging was performed on all slides according to multiple scoring systems and criteria for PBC. Liver samples were obtained from Mdr2 ^-/- mice treated with or without UDCA. Samples were processed for histology, immunohistochemistry, and immunofluorescence.

Results

Ductular reaction in people with PBC correlated with the disease stage and liver fibrosis, but not with disease activity; an extensive ductular reaction correlated with serum alkaline phosphatase levels at diagnosis, response to UDCA, and individuals' estimated survival, independently from other histological parameters, including disease stage. In people with PBC, reactive ductules were associated with the establishment of junctions with bile canaliculi and with fibrogenetic cell activation. Consistently, in a mouse model of intrahepatic cholestasis, UDCA treatment was effective in reducing ductular reaction and fibrosis and increasing ductular-canalicular junctions.

Conclusions

Extensive ductular reaction outlines a severe histologic phenotype in PBC and is associated with an inadequate therapy response and a worse estimated prognosis.

Lay summary

In people affected by primary biliary cholangitis (PBC), the histological appearance of extensive ductular reaction identifies individuals at risk of progressive fibrosis. Ductular reaction at diagnosis correlates with the lack of response to first-line therapy with ursodeoxycholic acid and serves to restore ductular-canalicular junctions in people with PBC. Assessing ductular reaction extension at diagnosis may add valuable information for clinicians.

UK-Wide Multicenter Evaluation of Second-line Therapies in Primary Biliary Cholangitis

BACKGROUND & AIMS

Thirty-to-forty percent of patients with primary biliary cholangitis inadequately respond to ursodeoxycholic acid. Our aim was to assemble national, real-world data on the effectiveness of obeticholic acid (OCA) as a second-line treatment, alongside non-licensed therapy with fibric acid derivatives (bezafibrate or fenofibrate).

METHODS

This was a nationwide observational cohort study conducted from August 2017 until June 2021.

RESULTS

We accrued data from 457 patients; 349 treated with OCA and 108 with fibric acid derivatives. At baseline/pre-treatment, individuals in the OCA group manifest higher risk features compared with those taking fibric acid derivatives, evidenced by more elevated alkaline phosphatase values, and a larger proportion of individuals with cirrhosis, abnormal bilirubin, prior non-response to ursodeoxycholic acid, and elastography readings >9.6kPa (P < .05 for all). Overall, 259 patients (OCA) and 80 patients (fibric acid derivatives) completed 12 months of second-line therapy, yielding a dropout rate of 25.7% and 25.9%, respectively. At 12 months, the magnitude of alkaline phosphatase reduction was 29.5% and 56.7% in OCA and fibric acid groups (P < .001). Conversely, 55.9% and 36.4% of patients normalized serum alanine transaminase and bilirubin in the OCA group (P < .001). The proportion with normal alanine transaminase or bilirubin values in the fibric acid group was no different at 12 months compared with baseline. Twelve-month biochemical response rates were 70.6% with OCA and 80% under fibric acid treatment (P = .121). Response rates between treatment groups were no different on propensity-score matching or on sub-analysis of high-risk groups defined at baseline.

CONCLUSION

Across the population of patients with primary biliary cholangitis in the United Kingdom, rates of biochemical response and drug discontinuation appear similar under fibric acid and OCA treatment.

Dynamic Risk Prediction of Response to Ursodeoxycholic Acid Among Patients with Primary Biliary Cholangitis in the USA

BACKGROUND

Ursodeoxycholic acid (UDCA) remains the first-line therapy for primary biliary cholangitis (PBC); however, inadequate treatment response (ITR) is common. The UK-PBC Consortium developed the modified UDCA Response Score (m-URS) to predict ITR (using alkaline phosphatase [ALP] > 1.67 times the upper limit of normal [*ULN]) at 12 months post-UDCA initiation). Using data from the US-based Fibrotic Liver Disease Consortium, we assessed the m-URS in our multi-racial cohort. We then used a dynamic modeling approach to improve prediction accuracy.

METHODS

Using data collected at the time of UDCA initiation, we assessed the m-URS using the original formula; then, by calibrating coefficients to our data, we also assessed whether it remained accurate when using Paris II criteria for ITR. Next, we developed and validated a dynamic risk prediction model that included post-UDCA initiation laboratory data.

RESULTS

Among 1578 patients (13% men; 8% African American, 9% Asian American/American Indian/Pacific Islander; 25% Hispanic), the rate of ITR was 27% using ALP > 1.67*ULN and 45% using Paris II criteria. M-URS accuracy was "very good" (AUROC = 0.87, sensitivity = 0.62, and specificity = 0.82) for ALP > 1.67*ULN and "moderate" (AUROC = 0.74, sensitivity = 0.57, and specificity = 0.70) for Paris II. Our dynamic model significantly improved accuracy for both definitions of ITR (ALP > 1.67*ULN: AUROC = 0.91; Paris II: AUROC = 0.81); specificity approached 100%. Roughly 9% of patients in our cohort were at the highest risk of ITR.

CONCLUSIONS

Early identification of patients who will not respond to UDCA treatment using a dynamic prediction model based on longitudinal, repeated risk factor measurements may facilitate earlier introduction of adjuvant treatment.

Anti-Mitochondrial Antibody Titers Decrease Over Time in Primary Biliary Cholangitis Patients With Ursodeoxycholic Acid Therapeutic Response: A Cohort Study Followed Up to 28 Years

Background

How anti-mitochondrial antibody (AMA) and liver biochemistry levels change in primary biliary cholangitis (PBC) patients treated with ursodeoxycholic acid (UDCA) remains unclear.

Methods

A 28-year cohort of 157 PBC patients was conducted. Patients with alkaline phosphatase (Alk-p) levels >1.67 × upper limit of normal after 1 year of UDCA treatment were considered nonresponders.

Results

At baseline, of 157 (mean age: 54.41 years), 136 (86.6%) were female, 51 (32.5%) had cirrhosis, and 128 (81.5%) had detectable AMAs (immunoglobulin G). UDCA nonresponders (n=61) were younger and had higher Alk-p and total bilirubin levels and cirrhosis rates than UDCA responders (n=84). Alk-p levels and cirrhosis were negatively associated with UDCA response. Regardless of cirrhosis and UDCA response, most PBC patients had decreased Alk-p and γ-glutamyltransferase levels at last follow-up (up to 28.73 years) compared with baseline levels. Patients with baseline cirrhosis (2.78 ± 2.56 vs. 6.84 ± 9.00 mg/dL, p=0.024) and UDCA nonresponders (2.54 ± 2.19 vs. 4.51 ± 6.99 mg/dL, p=0.006) had increased total bilirubin levels while patients without cirrhosis (AST: 91.5 ± 84.5 vs. 58.9 ± 43.7 U/L, p<0.001; ALT: 107.3 ± 122.5 vs. 50.7 ± 36.8 U/L, p<0.001) and UDCA responders (AST: 83.8 ± 101.3 vs. 45.58 ± 38.42 U/L, p=0.014; ALT: 95.10 ± 144.6 vs. 39.12 ± 30.65 U/L, p=0.009) had decreased aminotransferase levels. Only UDCA responders had decreased AMA titers from 1 year after UDCA treatment (p=0.028) until the last follow-up (p<0.001).

Conclusions

UDCA responders exhibited decreased AMA titers 1 year after treatment. Regardless of UDCA response, PBC patients showed improved cholestatic features, but only UDCA responders and patients without baseline cirrhosis exhibited attenuated hepatobiliary damage following UDCA treatment.

The National Audit of Primary Biliary Cholangitis (PBC) in the United Kingdom: Defining the Audit Dataset and Data Collection System

Primary biliary cholangitis (PBC) is a debilitating chronic liver disease that progresses to cirrhosis with attendant complications in a substantial proportion of patients. It is a major cause of liver-related morbidity and mortality in the United Kingdom (UK). The British Society of Gastroenterology (BSG) published guidelines on PBC management, which included key audit standards. Therefore, we propose the first UK-wide audit of the management of PBC, sanctioned by the BSG and the British Association for Study of the Liver (BASL), to benchmark NHS trusts and health boards against these audit standards as a guide to targeted improvement in the delivery of PBC-related health care.

Primary Biliary Cholangitis and Primary Sclerosing Cholangitis: Current Knowledge of Pathogenesis and Therapeutics

Cholangiopathies encompass various biliary diseases affecting the biliary epithelium, resulting in cholestasis, inflammation, fibrosis, and ultimately liver cirrhosis. Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the most important progressive cholangiopathies in adults. Much research has broadened the scope of disease biology to genetic risk, epigenetic changes, dysregulated mucosal immunity, altered biliary epithelial cell function, and dysbiosis, all of which interact and arise in the context of ill-defined environmental triggers. An in-depth understanding of the molecular pathogenesis of these cholestatic diseases will help clinicians better prevent and treat diseases. In this review, we focus on the main underlying mechanisms of disease initiation and progression, and novel targeted therapeutics beyond currently approved treatments.

The latest research trends in primary biliary cholangitis: a bibliometric analysis

The bibliometric analysis uses the citation count of an article to measure its impact in the scientific community, but no study has been undertaken to determine the most influential papers in the field of primary biliary cholangitis (PBC). This study aimed to investigate the global research interest regarding PBC in dentistry using a bibliometric approach. We searched the Web of Science Core Collection database to find the top 100 most cited (T100) articles focusing on PBC. The information about each article including citations, authors, journals, countries, institutions, and keywords was recorded for bibliometric analysis. The T100 articles related to PBC were published from 1983 to 2019 and were originated from 26 countries. A total of 805 different authors were from 342 different institutions, and articles written by them were published in 35 journals. The five most frequently occurring keywords were "biochemical response," "ursodeoxycholic acid," "primary biliary cirrhosis," "antimitochondrial antibody," and "autoimmunity." The T100 articles were classified into different research focuses: pathogenesis (41%), treatment (20%), prognosis (12%), epidemiology (9%), diagnosis (8%), and others (10%). These 100 articles included 32 observational studies, 29 basic research articles, 15 reviews, eight meta-analyses, 12 clinical trials, and four clinical guidelines. The 100 top-cited articles are marked with the leading countries, institutions, journals, hotspots, and development trends in the PBC field that could provide the foundation for further investigations.

The Serum Proteome and Ursodeoxycholic Acid Response in Primary Biliary Cholangitis

BACKGROUND AND AIMS

Stratified therapy has entered clinical practice in primary biliary cholangitis (PBC), with routine use of second-line therapy in nonresponders to first-line therapy with ursodeoxycholic acid (UDCA). The mechanism for nonresponse to UDCA remains, however, unclear and we lack mechanistic serum markers. The UK-PBC study was established to explore the biological basis of UDCA nonresponse in PBC and identify markers to enhance treatment.

APPROACH AND RESULTS

Discovery serum proteomics (Olink) with targeted multiplex validation were carried out in 526 subjects from the UK-PBC cohort and 97 healthy controls. In the discovery phase, untreated PBC patients (n = 68) exhibited an inflammatory proteome that is typically reduced in scale, but not resolved, with UDCA therapy (n = 416 treated patients). Nineteen proteins remained at a significant expression level (defined using stringent criteria) in UDCA-treated patients, six of them representing a tightly linked profile of chemokines (including CCL20, known to be released by biliary epithelial cells (BECs) undergoing senescence in PBC). All showed significant differential expression between UDCA responders and nonresponders in both the discovery and validation cohorts. A linear discriminant analysis, using serum levels of C-X-C motif chemokine ligand 11 and C-C motif chemokine ligand 20 as markers of responder status, indicated a high level of discrimination with an AUC of 0.91 (CI, 0.83-0.91).

CONCLUSIONS

UDCA under-response in PBC is characterized by elevation of serum chemokines potentially related to cellular senescence and was previously shown to be released by BECs in PBC, suggesting a potential role in the pathogenesis of high-risk disease. These also have potential for development as biomarkers for identification of high-risk disease, and their clinical utility as biomarkers should be evaluated further in prospective studies.