Gilead Sciences, Inc. (NASDAQ:GILD) today announced positive results from a Phase 3 study in people with primary biliary cholangitis (PBC), showing that treatment with Livdelzi® (seladelpar) led to significantly more patients achieving normalization of alkaline phosphatase (ALP), a key liver marker of disease progression, compared with placebo after 52 weeks. The primary endpoint was defined as a composite of ALP ≤ 1.0× upper limit of normal (ULN) and a ≥ 15% decrease from baseline.

These findings were observed in people with inadequately controlled disease, defined as having ALP levels above the ULN and below 1.67×ULN, with an incomplete response or intolerance to ursodeoxycholic acid (UDCA). This population has been underrepresented in prior randomized trials despite being commonly seen in clinical practice.

The safety profile of seladelpar observed in IDEAL was consistent with previously reported Livdelzi studies, with no new safety concerns identified.

"Together with prior pivotal Phase 3 RESPONSE data, which established Livdelzi as the first and only PBC treatment to demonstrate statistically significant reductions in both disease markers and pruritus versus placebo, IDEAL further strengthens support for the efficacy and safety profile of Livdelzi," said Cynthia Levy, MD, Professor of Clinical Medicine and Hepatology, University of Miami Miller School of Medicine. "These results extend the evidence base for Livdelzi to a broader population of people living with PBC and support ALP normalization as an achievable therapeutic goal in patients with ALP between 1 to 1.67xULN."

In PBC, ALP is a key disease marker associated with disease activity and long‑term outcomes. ALP levels above normal, including in the 1.0 to 1.67×ULN range, are associated with increased risk of progression to liver transplant or death compared with normalized ALP levels.

"Advancing and leading in liver disease requires a sustained commitment to addressing areas of persistent unmet need," said Swati Tole, MD, MS, Senior Vice President, Clinical Development, Inflammation, Gilead Sciences. "As the field moves toward ALP normalization as an important treatment goal in PBC, we are focused on generating robust, clinically meaningful evidence to better understand treatment response and inform care—translating scientific progress into meaningful patient impact."