Clinical trial design, biomarkers and end points in metabolic and alcohol-related liver disease.

Metabolic and alcohol-related liver disease (MetALD) is a newly defined entity within the spectrum of steatotic liver disease, characterized by the interplay of cardiometabolic risk factors and alcohol consumption. The evolving epidemiology and complex pathophysiology of MetALD present unique challenges and opportunities for clinical trial design. Inclusion criteria should require simultaneous evidence of metabolic dysfunction (at least two cardiometabolic features) and verified quantifiable alcohol exposure recorded over the preceding 3-6 months. Traditional histological end points are limited by invasiveness, sampling error and interpretative variability. Thus, imaging modalities, serum-based fibrosis biomarkers and quantitative measures of alcohol intake are gaining relevance as non-invasive, reproducible and patient-centric end points aiming to improve trial feasibility. Furthermore, incorporating alcohol biomarkers, stratifying patients by metabolic risk factor burden, and using adaptive designs of trials might enhance the precision and generalizability of MetALD clinical trials. Although uncertainties remain regarding optimal patient selection criteria, event rates and the dynamic interplay between metabolic dysfunction and alcohol intake, ongoing research efforts aim to refine diagnostic criteria, standardize methodologies and validate novel end points. These advances will ultimately accelerate drug development, improve trial efficiency and foster interventions to treat MetALD.