A Research Study on How Semaglutide Works in People With Fatty Liver Disease and Liver Damage

Inclusion Criteria: * Male or female, aged 18-75 years (both inclusive) at the time of signing informed consent. * Histologic evidence of NASH and fibrosis stage 4 according to the NASH CRN classification based on central pathologist evaluation of a liver biopsy obtained within 360 days prior to screening. In subjects who have never had a liver biopsy showing NASH and F4, liver stiffness above 14 kPa by FibroScan® at screening must be documented before subjects can have a trial-related liver biopsy * A histological NAFLD activity score (NAS) equal to or above 3 with a score of 1 or more in lobular inflammation and hepatocyte ballooning based on central pathologist evaluation * Body mass index equal to or above 27 kg/m\^2 Exclusion Criteria: * Presence or history of hepatic decompensation (e.g. ascites, variceal bleeding, hepatic encephalopathy or spontaneous bacterial peritonitis) or liver transplantation * Presence or history of gastroesophageal varices within the past 360 days prior to screening. For subjects with no known history of gastroesophageal varices and with a Fibroscan® equal to or above 20 kPa and thrombocytes equal to or below 150,000, a esophagogastroduodenoscopy must be performed to evaluate presence of gastroesophageal varices * Presence or history of hepatocellular carcinoma * Treatment with vitamin E (at doses equal to or above 800 IU/day) or pioglitazone which has not been at a stable dose in the opinion of the investigator in the period from 90 days pr…