Amgen (AMGN) Stock Jumps 4% on Positive Phase 3 Results for Potential First-of-Its-Kind Sjögren's Drug
Key Takeaways
- •Amgen (AMGN) shares climbed roughly 4% in premarket trading to $406.02 after positive Phase 3 results for its Sjögren's disease drug dazodalibep.
- •The Phase 3 OASIZ 301 trial met its primary endpoint, with about 621 patients showing statistically meaningful improvement in disease activity at Week48, with benefits visible as early as Week 4.
- •If approved, dazodalibep would become the first FDA-approved treatment for Sjögren's disease, a systemic autoimmune condition that currently has no approved medicines.
- •The most common side effects were nasopharyngitis, urinary tract infections, hypertension, and infusion-related reactions, with low discontinuation rates similar between treatment and placebo groups.
- •Novartis is developing a competing BAFF-targeting drug, ianalumab, which an analyst expects to win approval in coming months, while Amgen plans to present full OASIZ 301 data at an upcoming medical conference.
Amgen (AMGN) shares climbed roughly 4% in premarket trading on Tuesday, touching $406.02 shortly after the open, after the biotechnology giant reported positive topline results from a Phase 3 trial of dazodalibep, its experimental treatment for Sjögren's disease.
The study, known as OASIZ 301, met its primary endpoint. Patients showed a statistically meaningful improvement in systemic disease activity at Week 48, as measured by the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI). The stock's advance carried AMGN back above its 50-day moving average. Phase 3 trials are typically the final stage of clinical testing before a drug can considered for regulatory approval, which frames the weight of the result.
Approximately 621 patients with moderate-to-severe systemic Sjögren's disease were enrolled in the trial. Improvements appeared as early as Week 4 and held through the end of the 48-week study period.
Sjögren's is a systemic autoimmune disease that causes dryness, fatigue, and chronic pain, and it can affect major organs. There are currently no FDA-approved medicines for the condition, and that treatment gap sits at the center of the story: if dazodalibep clears regulatory review, it would become the first approved treatment for the disease.
How Dazodalibep Works
Dazodalibep is a CD40L antagonist fusion protein. It works by disrupting the interactions between T cells, B cells, and other immune cells that drive the disease.
Jay Bradner, Amgen's head of research and development, said the speed and durability of the results reinforced the company's confidence in the drug and its broader Phase 3 program.
The most common side effects observed in the trial were nasopharyngitis, urinary tract infections, hypertension, and infusion-related reactions, most of which were mild to moderate. Discontinuation rates due to side effects were low and similar between the treatment and placebo groups.
Competitive Landscape
Amgen is not alone in this space. Novartis (NVS) is also developing a Sjögren's treatment, ianalumab, which takes a different approach by targeting the BAFF protein. In its trial, ianalumab showed 1.3- to 1-point improvements over placebo on a 42-point symptom scale. Leerink Partners analyst David Risinger said the drug is likely to win approval in the coming months. Risinger rates AMGN stock a market perform.
Amgen plans to present full data from OASIZ 301 at an upcoming medical conference, and the detailed readout should offer a clearer picture of how dazodalibep stacks up against ianalumab.
A second Phase 3 study, OASIZ 303, is evaluating dazodalibep in patients with moderate-to-severe symptomatic Sjögren's disease and is expected to wrap up in Q4 2026 — part of the broader Phase 3 program Bradner referenced when discussing the company's confidence in the drug.
