Livdelzi Achieves ALP Normalisation in 75.4% of PBC Patients in Phase 3 IDEAL Study – Gilead Sciences
Gilead Sciences, Inc. announced the detailed results from the Phase 3 IDEAL study, which demonstrated that the majority of participants living with PBC and treated with Livdelzi (seladelpar) achieved the alkaline phosphatase (ALP) normalization composite endpoint defined as a composite of ALP ≤ 1.0× upper limit of normal (ULN) and a ≥ 15% decrease from baseline. ALP is a key marker of disease activity and long-term outcomes in PBC. These results can expand understanding of treatment effects and inform evolving treatment goals for people living with PBC.
Key Highlights
– At Week 52, 75.4% (49/65) of participants who received Livdelzi achieved the ALP normalization composite endpoint versus 16.1% (5/31) of participants receiving placebo.
– Results will be presented at The Liver Meeting 2026, hosted by the American Association for the Study of Liver Diseases (AASLD), November 5-9 in Denver, Colorado, and have been accepted for upcoming publication in the Journal of Hepatology.
– Gilead is engaging with global regulatory authorities to discuss these results.
IDEAL is a Phase 3, randomized, double-blind, placebo-controlled clinical study evaluating Livdelzi in adults living with PBC who have ALP levels above normal yet below the 1.67× ULN threshold typically required for inclusion in other PBC randomized controlled trials (RCTs). It is the first clinical trial to evaluate Livdelzi in people with inadequately controlled disease defined as ALP levels of 1-1.67× ULN despite receiving ursodeoxycholic acid (UDCA) for 12 months or with intolerance to UDCA.
“People with PBC whose alkaline phosphatase remains elevated but below 1.67 times the upper limit of normal have been largely excluded from previous pivotal trials of second-line therapies. IDEAL provides randomized, placebo-controlled evidence that seladelpar can improve biochemical response in this population. These findings can inform individualized treatment discussions, taking into account each individual’s risk of disease progression, symptoms, and potential benefits and risks of additional therapy.” – Cynthia Levy, MD, University of Miami Miller School of Medicine.
ALP is a key marker of disease activity with levels above normal associated with an increased risk of disease progression and poorer long-term outcomes, such as liver failure. Historically, the threshold for clinical study inclusion has been ALP levels >1.67× ULN. Recent clinical guidance recognizes ALP normalization as an ideal treatment goal in PBC. Results from IDEAL expand the evidence base by demonstrating that a significantly higher proportion of people with baseline ALP levels between 1-1.67× ULN and treated with Livdelzi can achieve ALP normalization compared to placebo. The response was evident after one month of treatment (52.3% versus 6.5% receiving placebo) and sustained through Week 52.
“The IDEAL study evaluated the impact of initiating second-line treatment in people living with PBC who have lower levels of baseline ALP elevation compared to prior clinical trials. A significantly greater proportion of people with elevated ALP levels, but below the threshold typically studied, achieved ALP normalization with Livdelzi, supporting ALP normalization as an achievable treatment goal. Together with the broader Livdelzi clinical program, IDEAL reinforces the importance of continuing to raise expectations for PBC care across a wide range of patients.” – Swati Tole, MD, MS, Senior Vice President, Clinical Development, Inflammation, Gilead Sciences.
The safety profile of Livdelzi observed in IDEAL was consistent with previously reported Livdelzi studies, with no new safety concerns identified. Adverse event incidence was generally similar between Livdelzi and placebo groups; serious adverse events occurred in 3.1% and 12.9% of individuals, respectively, and none were deemed related to trial drug.
