Amgen's Phase III OASIZ 301 trial of dazodalibep met its primary endpoint, demonstrating a statistically significant and clinically meaningful reduction in systemic disease activity on the ESSDAI at 48 weeks, with improvements seen from week 4. Adverse events were generally mild to moderate, including nasopharyngitis, urinary tract infection, hypertension and infusion reactions. Dazodalibep, a potential first-in-class CD40L antagonist acquired in Amgen's $27.8 billion purchase of Horizon Therapeutics, is also being evaluated in OASIZ 303, due to complete in Q4 2026. Competing candidates include Novartis's ianalumab, RemeGen's telitacicept and J&J's nipocalimab.
Amgen’s Dazodalibep Hits Primary Endpoint in Phase III Sjögren's Trial, Boosting Approval Prospects
Amgen acquired the drug through its $27.8bn buyout of Horizon Therapeutics. Credit: JHVEPhoto / Shutterstock.com
Amgen has reported that its Phase III OASIZ 301 trial of dazodalibep met the study's primary endpoint, strengthening prospects for the first-ever approved therapies for Sjögren's disease.
Study Results
In the double-blind, randomized, placebo-controlled OASIZ 301 study (NCT06104124), patients treated with dazodalibep experienced a statistically significant and clinically meaningful reduction in systemic disease activity measured by the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) at 48 weeks. The trial noted that improvements were detectable as early as week 4.
About ESSDAI
ESSDAI is a validated clinical instrument that quantifies systemic disease activity across organ systems in people with Sjögren's disease and is widely used in clinical trials to assess treatment impact.
Safety Profile
The most frequently reported adverse events were nasopharyngitis, urinary tract infection, hypertension, and infusion-related reactions. These events were generally described as mild to moderate in severity.
"Sjögren's disease is a complex and heterogeneous autoimmune disease, and no two people experience it in exactly the same way. It can be relentless, creating a real burden for people living with the disease and affecting their quality of life," said Janet Church, president and CEO of the Sjögren's Foundation.
Next Steps and Regulatory Path
Amgen plans to present detailed OASIZ 301 data at an upcoming medical meeting. The company is also conducting a second Phase III trial, OASIZ 303 (NCT06245408), which is expected to complete in Q4 2026 and will contribute additional evidence for potential regulatory submissions.
Mechanism and Corporate Background
Dazodalibep is a potential first-in-class CD40L antagonist fusion protein designed to blunt immune activation by interrupting interactions among T cells, B cells and other antigen-presenting cells. Amgen acquired the candidate through its $27.8 billion acquisition of Horizon Therapeutics in 2023.
Context and Competition
Sjögren's disease is a systemic autoimmune disorder characterized by extensive dryness and, in many patients, profound fatigue, chronic pain, organ involvement, neuropathy and an increased risk of lymphoma. There are currently no FDA-approved therapies specifically for Sjögren's disease, which makes positive Phase III results highly significant.
However, dazodalibep faces competition from several advancing programs. Notably, Novartis's BLyS/BAFF-targeting ianalumab received Breakthrough Therapy designation from the US Food and Drug Administration in January 2026 and has submitted applications based on two positive Phase III trials. Other promising candidates include RemeGen's telitacicept and Johnson & Johnson's Imaavy (nipocalimab).
Amgen's announcement positions dazodalibep as a leading contender in a rapidly evolving field; full trial details and peer-reviewed data will be important for regulators, clinicians and patients evaluating the drug's benefit-risk profile.
Help us improve.
