This study is testing a new drug called **NST-6179** for people with **Intestinal Failure-Associated Liver Disease (IFALD)**, a condition where the liver is damaged due to intestinal problems. The study will see how safe and tolerable this drug is and how the body processes and responds to it. The study is done in two parts, with each part involving **18 people**. Part A will have participants take **800 mg** of the drug or a placebo daily for **4 weeks**, while Part B will use **1200 mg** for **12 weeks**. A placebo is a harmless pill given to see if the drug actually works. Participants need to be at least **16 years old** and have been on **parenteral nutrition (PN)**, which is receiving nutrients through a vein, for at least **6 months**. Some medical conditions will prevent you from joining, like other liver diseases or severe liver damage. This study will help discover if NST-6179 can be a helpful treatment for people with IFALD.

• Study involves two parts with different doses and durations.
• Participants need to be on parenteral nutrition for at least 6 months.
• Eligibility requires stable liver disease without cirrhosis.