Gilead Sciences will present compelling new long-term efficacy data for Livdelzi (seladelpar) in primary biliary cholangitis (PBC) at The Liver Meeting 2025, hosted by the American Association for the Study of Liver Diseases (AASLD) from November 7-11 in Washington, D.C. The pharmaceutical company plans to share findings from more than 35 accepted abstracts, including three late-breaking presentations that demonstrate the potential for sustained liver health improvements.
Three-Year Interim Analysis Shows Promise for Liver Health
The centerpiece of Gilead's presentations will be three-year interim data from the ongoing ASSURE study, which demonstrates that Livdelzi may help stabilize or improve liver health in PBC patients. According to the company, these findings explore how Livdelzi is being used in clinical practice and its potential impact on liver health outcomes.
"The data we're sharing at The Liver Meeting reflect our continued dedication to advancing science that meaningfully improves the lives of people affected by liver disease," said Anu Osinusi, Vice President, Clinical Research for Hepatitis, Respiratory and Emerging Viruses at Gilead. "These interim long-term findings in PBC deepen our understanding of disease progression and highlight the potential to help improve patients' liver health and symptoms."
Real-World Evidence and Clinical Trial Extensions
Three late-breaking presentations will provide comprehensive insights into Livdelzi's clinical performance. The studies include real-world treatment experience following the withdrawal of obeticholic acid (LB#5037), liver stiffness outcomes from the three-year interim analysis of the ASSURE study (LB#5031), and long-term pruritus data from the RESPONSE trial and its open-label extension (LB#5015).
These presentations will explore patient-reported experiences with itch over time, a significant quality-of-life concern for PBC patients. The data encompasses both controlled trial settings and real-world clinical practice, providing a comprehensive view of Livdelzi's therapeutic impact.
Comprehensive Liver Disease Research Portfolio
Beyond PBC research, Gilead will present data from its viral hepatitis portfolio. In hepatitis delta virus (HDV), the company will share integrated analyses from the MYR204 and MYR301 studies, investigating the long-term safety and efficacy of bulevirtide for chronic HDV treatment.
Additional presentations will include analysis from the Phase 3 ALLIANCE study examining HIV/HBV co-infected participants who achieved hepatitis B virus surface antigen (HBsAg) loss, a marker of HBV functional cure, after starting tenofovir-based treatments. Data from a Phase 1b study on novel investigational therapeutic HBV vaccines GS-2829 and GS-6779 will also be presented.
Regulatory Status and Clinical Development
Livdelzi obtained accelerated approval from the U.S. Food and Drug Administration in August 2024 for the treatment of PBC. The drug received Breakthrough Therapy Designation and Orphan Drug Designation for PBC treatment. As part of the FDA accelerated approval, Gilead has committed to AFFIRM, a long-term outcomes study in people with compensated cirrhosis.
The European Commission granted conditional marketing authorization for Lyvdelzi (seladelpar) in February 2025 for PBC treatment in combination with ursodeoxycholic acid (UDCA) in adults with inadequate response to UDCA alone, or as monotherapy in those unable to tolerate UDCA. In October 2025, Lyvdelzi received conditional marketing authorization in Canada for the same indication.
Safety Profile and Clinical Considerations
Livdelzi is an oral PPAR-delta agonist with anticholestatic, anti-inflammatory, antipruritic, and antifibrotic effects. The most common adverse reactions (≥5%) include headache (8%), abdominal pain (7%), nausea (6%), abdominal distension (6%), and dizziness (5%). Fractures occurred in 4% of Livdelzi-treated patients compared to no placebo-treated patients in clinical trials.
The drug carries warnings for dose-related increases in serum transaminase levels and requires monitoring of liver function tests. Use is not recommended in patients with decompensated cirrhosis, and the drug should be avoided in patients with complete biliary obstruction.
