Arnatar Therapeutics Announces First Patient Dosed in Investigator-Initiated Trial of ART104 for Alagille Syndrome (ALGS)
SUZHOU, CHINA; SAN DIEGO, CA, Sep. 15, 2025 –Arnatar Therapeutics, a biotechnology company pioneering RNA-based therapies for severe and underserved diseases, today announced that the first patient has been dosed with ART104, a first-in-class antisense oligonucleotide (ASO) drug designed to treat Alagille Syndrome (ALGS) at its genetic root cause. No drug related AEs was observed, ART104 demonstrated well tolerated safety profile.
The investigator-initiated trial (IIT) is being conducted by Prof. Jianshe Wang at the Children’s Hospital of Fudan University, a globally recognized leader in ALGS research and care. The study will evaluate the safety, pharmacokinetics/pharmacodynamics (PK/PD), and efficacy of ART104 in patients living with ALGS.
“Dosing the first patient with ART104 is an important milestone not only for Arnatar but also for the ALGS community,” said Dr. Yanfeng Wang, COO and Head of Development. “By directly addressing Jag1 haploinsufficiency, ART104 has the potential to fundamentally change outcomes for patients and families living with this devastating disease.”
ART104: First-in-Class Approach to Restoring Jag1
ART104 is powered by Arnatar’s proprietary ACT-UP1 technology and is the first ASO therapeutic designed to upregulate Jag1 protein. Jag1 haploinsufficiency is recognized as the major cause of ALGS, a devastating multi system disease characterized by bile duct paucity and liver dysfunction.
In preclinical studies, ART104 demonstrated:
• Significant restoration of liver bile ducts in disease animal models
• Robust tolerability profile across multiple studies
ART104 has received both Orphan Drug Designation (ODD) and Pediatric Rare Disease Designation (PRDD) from the U.S. Food and Drug Administration (FDA), underscoring its potential as a transformative therapy.
Aiming to Change the Standard of Care
If successful, ART104 could offer the first efficient therapeutic approach targeting the underlying cause of ALGS, moving beyond symptomatic care to a disease-modifying treatment.
About Arnatar Therapeutics
Arnatar Therapeutics is a clinical-stage biotechnology company redefining the possibilities of RNA medicine. With its proprietary DARGER™ platform, Arnatar uniquely integrates best-in-class siRNA gene silencing with first-in-class antisense oligonucleotides (ASOs) that upregulate protein expression. This dual-modality platform empowers Arnatar to develop RNA medicines that either silence harmful disease drivers through siRNA or restore essential protein function through up-regulating ASOs, opening new therapeutic possibilities for previously untreatable conditions. The company’s pipeline spans across cardiometabolic, liver, kidney, and central nervous system diseases, targeting areas of high unmet medical need. Founded by leaders in RNA therapeutics and backed by leading biotech investors, Arnatar is committed to transforming RNA innovation into life-changing, programmable medicines for patients worldwide.