This study is for adults aged 18 and up with a liver disease called NASH (non-alcoholic steatohepatitis) or MASH (metabolic-associated steatohepatitis) and a body mass index (BMI) of 27 or more (25 for Asian participants). It checks if a medicine called survodutide can help improve liver function. Participants are randomly placed into two groups: one receives survodutide and the other receives a placebo, which looks the same but contains no medicine. They do not know which group they are in. Participants give themselves an injection under the skin once a week and get advice on diet and exercise. The study lasts up to 4.5 years, with regular check-ins every few weeks for the first year and a half, and every three months afterwards. Doctors will monitor health, side effects, and liver function using imaging tests. Participants will also fill out symptom questionnaires. Results will determine if the treatment is effective.

• Length of Study: Up to 4.5 years
• Visits: Regular check-ins every few weeks, then every 3 months
• Participation: Random assignment to receive medicine or placebo