Maralixibat: What It Is, How It Works, and Key Uses in Liver Disease

When it comes to rare liver diseases in children, maralixibat, a once-daily oral medicine that blocks bile acid reabsorption in the gut. Also known as livmarli, it’s one of the first drugs specifically approved to treat progressive familial intrahepatic cholestasis, or PFIC. This isn’t a common drug—it’s designed for a small group of patients with genetic liver disorders that cause bile to back up, leading to severe itching, poor growth, and liver damage over time.

Maralixibat works by targeting the ileal bile acid transporter, a protein in the small intestine that normally recycles bile acids back into the body. In kids with PFIC, this system is broken. Bile acids build up in the liver, causing inflammation and scarring. Maralixibat stops that recycling, letting excess bile acids pass out in stool instead. It doesn’t fix the genetic root cause, but it reduces the toxic buildup that makes kids sick. This leads to less itching, better weight gain, and slower liver damage. It’s not a cure, but for many families, it’s the difference between constant discomfort and some normal days.

Maralixibat is used for children as young as 3 months old with PFIC types 1, 2, or 3. It’s also being studied for other cholestatic conditions like Alagille syndrome, where bile ducts are underdeveloped. The drug is taken daily with food, and side effects include stomach issues like diarrhea and vomiting—common at first but often improve over time. Doctors monitor liver enzymes and growth closely. What makes maralixibat stand out is that it’s one of the few treatments that directly targets the bile acid cycle, not just symptoms. Other drugs like ursodiol help too, but they don’t block reabsorption the same way.

Related to this are other treatments like cholestatic liver disease, a group of disorders where bile flow is reduced or blocked, leading to toxin buildup, and bile acid transport, the biological process that moves bile acids between liver, gut, and bloodstream. These concepts are central to understanding why maralixibat works—and why it’s not used for every liver problem. For example, it won’t help someone with alcohol-related liver damage or viral hepatitis. It’s targeted, precise, and only makes sense in specific genetic cases.

You’ll find posts here that dig into how drugs like maralixibat are developed, how they compare to older treatments, and what families need to know about managing side effects. There are also guides on liver function tests, how to track growth in kids on long-term therapy, and what to ask your doctor when a new drug is prescribed. This isn’t a general liver health page—it’s focused on the real-world use of targeted therapies for rare conditions. If you’re dealing with PFIC, Alagille, or another cholestatic disorder, these articles are meant to help you understand what’s happening, what’s possible, and what to expect next.