A Study of CS060380 Tablets in Patients With MASH and Obesity

this study is looking at a new investigational medicine called CS060380, when used together with semaglutide, in adults who have both metabolic dysfunction-associated steatohepatitis (MASH) and obesity. MASH is a condition where too much fat builds up in the liver, leading to inflammation and damage. Obesity is a major risk factor for this condition. This is a Phase II clinical trial, which means we are testing the medicine to see if it works and is safe. The study will last up to 54 weeks, which is a little over a year. It includes: * A screening period of up to 2 weeks to check if you are eligible to take part. * A 36-week double-blind treatment period, where you will be randomly assigned (like flipping a coin) to receive either the study drug CS060380 or a placebo (an inactive pill that looks like the study drug). Both groups will also receive semaglutide, which is an approved medicine for weight management. Neither you nor your doctor will know which treatment you are receiving. * A 16-week open-label period, where all participants will receive CS060380. The main goal of this study is to see how the study drug affects the amount of fat in the liver, measured by a special MRI scan, and body weight. We will also monitor your overall health and safety throughout the study by checking your vital signs, doing blood and urine tests, and asking about any side effects you might experience. About 120 participants will take part in this study at almost 15 different hospitals across China, with Ruijin Hospital in Shanghai as the main study site.

Inclusion Criteria: * Age 18 to 65 years (inclusive), male or female. * Liver fat content ≥10% as measured by MRI-PDFF at screening. * BMI ≥30 kg/m². * Body weight change ≤5% during the 3 months prior to screening with only diet and exercise control (self-reported). The weight change is calculated as: (Maximum weight - Minimum weight within 3 months before screening) / Maximum weight × 100%. * Glycated hemoglobin (HbA1c) \