Combined effects of PNPLA3, TM6SF2 and HSD17B13 variants on severity of biopsy-proven non-alcoholic fatty liver disease.

OBJECTIVE Several single-nucleotide polymorphisms have been identified to be disadvantageous or protective in regard to disease severity in patients with non-alcoholic fatty liver disease (NAFLD). However, it is unclear, whether including genetic risk factor(s) either alone or combined into risk stratification algorithms for NAFLD actually provides incremental benefit over clinical risk factors. DESIGN Patients with biopsy-proven NAFLD were genotyped for the PNPLA3-rs738409(minor allele:G), TM6SF2-rs58542926(minor allele:T) and HSD17B13- rs72613567 (minor allele:TA) variants. The NAFLD activity score (NAS) and fibrosis stage (F0-F4) were used to grade and stage all liver biopsy samples. Patients from seven centers throughout Central Europe were considered for the study. RESULTS 703 patients were included: NAS ≥ 5:173(24.6%); Fibrosis: F3-4:81(11.5%). PNPLA3 G/G genotype was associated with a NAS ≥ 5(aOR 2.23, p = 0.007) and advanced fibrosis (aOR-3.48, p < 0.001).TM6SF2 T/- was associated with advanced fibrosis (aOR 1.99, p = 0.023). HSD17B13 TA/- was associated with a lower probability of NAS ≥ 5(TA/T: aOR 0.65, p = 0.041, TA/TA: aOR 0.40, p = 0.033). Regarding the predictive capability for NAS ≥ 5, well-known risk factors (age, sex, BMI, diabetes, and ALT; baseline model) had an AUC of 0.758, Addition of PNPLA3(AUC 0.766), HSB17B13(AUC 0.766), and their combination(AUC 0.775), but not of TM6SF2(AUC 0.762), resulted in a higher diagnostic accuracy of the model. Addition of genetic markers for the prediction of advanced fibrosis (baseline model: age, sex, BMI, diabetes: AUC 0.777) resulted in a higher AUC if PNPLA3(AUC 0.789), and TM6SF2(AUC 0.786) but not if HSD17B13(0.777) were added. CONCLUSION In biopsy-proven NAFLD, PNPLA3 G/-, TM6SF2 T/- and HSD17B13 TA/- carriage are associated with severity of NAFLD. Incorporating these genetic risk factors into risk stratification models might improve their predictive accuracy for severity of NAFLD and/or advanced fibrosis on liver biopsy

Norursodeoxycholic acid versus placebo in the treatment of non-alcoholic fatty liver disease: a double-blind, randomised, placebo-controlled, phase 2 dose-finding trial

Background Norursodeoxycholic acid is an orally administered side chain-shortened homologue of ursodeoxycholic acid that undergoes hepatic enrichment with hepatoprotective, anti-inflammatory, and antifibrotic activity. We assessed the efficacy of two doses of norursodeoxycholic acid versus placebo for the treatment of non-alcoholic fatty liver disease. Methods We did a multicentre, double-blind, placebo-controlled, randomised, phase 2 dose-finding clinical trial in tertiary referral hospitals and medical centres in Austria (n=6) and Germany (n=23) for patients with non-alcoholic fatty liver disease with or without diabetes. Patients with a clinical diagnosis of non-alcoholic fatty liver disease and serum alanine aminotransferase (ALT) concentrations of more than 0.8 times the upper limit of normal were randomly assigned (1:1:1) using a computer-generated central randomisation. Patients were randomly assigned to receive either norursodeoxycholic acid capsules at 500 mg per day or 1500 mg per day, or placebo, for 12 weeks with a subsequent 4-week follow-up period. All individuals involved in the trial were masked to treatment allocation. The primary efficacy endpoint was the mean relative percentage change in ALT concentrations between baseline and end of treatment assessed in the intention-to-treat population. This trial is registered with EudraCT, number 2013-004605-38. Findings Between March 30, 2015, and Sept 20, 2016, of 198 individuals included in the analysis, 67 patients were randomly assigned to receive 500 mg norursodeoxycholic acid, 67 to 1500 mg norursodeoxycholic acid, and 64 to placebo. A dose-dependent reduction in serum ALT between baseline and end of treatment was observed with norursodeoxycholic acid versus placebo, with a significant effect in the 1500 ing group (mean change -27.8%, 95% repeated CI -34.7 to -14.4; p<0.0001). Serious adverse events (n=6) and treatment-emergent adverse events (n=314) were reported in a similar proportion of patients across groups. 112 treatment-emergent adverse events occurred in the 1500 mg group, 99 in the 500 mg group, and 103 in the placebo group. The most frequent adverse events were headache, gastrointestinal disorders, and infections (eg, diarrhoea, abdominal pain, or nasopharyngitis). Interpretation Norursodeoxycholic acid at 1500 mg resulted in a significant reduction of serum ALT within 12 weeks of treatment when compared with placebo. Norursodeoxycholic acid was safe and well tolerated encouraging further studies. Copyright (C) 2019 Elsevier Ltd. All rights reserved