Kris Kowdley, MD: IBAT Inhibitors Provide Opportunity Against Alagille Syndrome

A drug class in continued development for a rare genetic disease is giving new hope to clinicians managing its difficult-to-treat, even possibly fatal, multifactorial symptoms in pediatric patients.

In an interview with HCPLive, Kris V. Kowdley, MD, director of the Liver Institute Northwest and professor of medicine at Elson S. Floyd College of Medicine at Washington State University, discussed Alagille syndrome, the rare condition commonly associated with cholestatic liver disease and a significant rate of pruritus among pediatric and adolescent patients. The former symptom is linked to significant risk of premature mortality; the latter symptom is a major burden on young patients and their caregivers.

“I think for patients with Alagille syndrome who have severe pruritus, they’re really affected by it—and these are children,” Kowdley said. “They may not be able to articulate or recognize their symptoms. And they suffer; it’s very impactful for their families and parents.”

In recent years, investigators have developed and built supporting clinical evidence for ileal bile acid transporter (IBAT) inhibitor therapies—a drug class that’s reached the market through the US Food and Drug Administration (FDA) and have shown benefit for cholestatic liver disease and improved patient outcomes relative to expected historical data.

“And now that we have this new class of drug that actually block reabsorption of bile acids in the terminal ileum, that’s been a major advance at least for treating the liver disease in patients with Alagille,” Kowdley said.

Another IBAT inhibitor, odevixibat, will be under FDA review for the treatment of Alagille syndrome this summer. Kowdley stressed its progression among other agents in the drug class is a key benefit for prescribing hepatologists.

“The fact we now have data suggesting not only improved outcomes but improved survival in comparison to historical control data is impactful for several reasons,” Kowdley said. Among the reasons is that he and colleagues can now use increasing real-world evidence to show effect of therapies like the number of IBAT inhibitors in development for Alagille syndrome and other forms of genetic cholestatic syndromes.

“I think these have the potential,” he explained. “Certainly, it’s less clear whether they’re going to modify disease, but it’s very clear that they have a very dramatic effect on improving quality of life.”