Gilead’s Phase 3 trial of Libdelzi met its primary endpoint, demonstrating the drug’s ability to normalize key markers of disease progression in patients with the rare liver disease primary biliary cholangitis (PBC).
In the IDEAL study, which compared Livdelzi with a placebo, Gilead’s tablets helped significantly more patients gain control of alkaline phosphatase (ALP) levels, a key signal of disease progression. The trial’s primary endpoint hinges on the number of patients whose ALP levels decrease by at least 15% from baseline and reach the normal range, the company announced Tuesday.
The trial included 96 participants between the ages of 18 and 75 who had poorly controlled PBC. This group of patients is associated with an increased risk of progression to liver transplantation or death compared to patients with normalized ALP levels, Gilead explained.
The study’s patient population included only those who had an incomplete response or intolerance to ursodeoxycholic acid (UDCA), the standard first-line treatment for PBC. UDCA treatment replaces bile acids, slows disease progression and improves liver function.
“These results extend the rationale for Livdelge to a broader population of patients with PBC and support normalization of ALP as an achievable treatment goal in patients with ALP between 1 and 1.67,” Cynthia Levy, MD, of the University of Miami Miller School of Medicine, said in the release.
Gilead said it will provide full results of the trial at an upcoming medical conference and will work with global regulatory authorities on the data.
Livdelzi received accelerated approval from the FDA in August 2024 for the second-line treatment of PBC.
The company acquired the drug, also known as Seradelpar, when it acquired CymaBay Therapeutics for $4.3 billion in early 2024. Gilead reported sales of Livdelge were $133 million in the first quarter of this year, up from $40 million in the same period in 2025.
In the second line of PBCs, Gilead competes with Ibsen and Genfit’s Iquilbo, also approved in 2024, which generated sales of 79 million euros ($93 million) in the first quarter.
Intercept last year pulled its PBC drug Ocaliva from the market after it failed to receive traditional FDA approval after receiving early approval in 2016.
