AstraZeneca announced positive results from a pre-specified interim analysis of the Phase III TULIP-SC trial, showing that subcutaneous administration of Saphnelo (anifrolumab) demonstrated a statistically significant and clinically meaningful reduction in disease activity compared to placebo in patients with systemic lupus erythematosus (SLE). The safety profile observed in the interim analysis was consistent with the known clinical profile of Saphnelo administered as an intravenous infusion.
The TULIP-SC trial evaluated the efficacy and safety of subcutaneous Saphnelo compared to placebo in participants with moderately to severely active, autoantibody-positive SLE, with both treatment groups receiving standard therapy including oral corticosteroids, antimalarials, and/or immunosuppressants.
Addressing Critical Unmet Medical Need
Systemic lupus erythematosus affects over 3.4 million people globally and can impact any organ, leading many patients to experience debilitating symptoms, irreversible organ damage and poor health-related quality of life. The disease is among the leading causes of death in young women in the US and disproportionately affects women in their prime, and those of Asian, Black or Hispanic racial/ethnic backgrounds.
While oral corticosteroids are often used to provide symptom relief for SLE patients, they are associated with adverse events and short-term benefits without targeting the underlying drivers of the disease, preventing patients from experiencing adequate disease control and achieving remission. An estimated 50% of people with SLE have irreversible organ damage within five years of diagnosis due to long-term corticosteroid use and disease activity. Even a small reduction in daily steroid use of 1 mg/day can lower the risk of organ damage.
Recent updates to clinical guidelines elevate the importance of treating to target remission or low disease activity and minimizing the use of oral corticosteroids.
Trial Design and Results
TULIP-SC is a Phase III, multicentre, randomised, double-blind, placebo-controlled study evaluating subcutaneous anifrolumab versus placebo in participants with moderately to severely active, autoantibody-positive SLE while receiving standard therapy. Patients recruited were aged 18 to 70 years and must have been taking either one or any combination of oral corticosteroids, antimalarial, and/or immunosuppressants.
In the trial, 367 participants on standard therapy were randomised 1:1 to receive 120mg subcutaneous dose of anifrolumab or placebo administered once weekly via an accessorised prefilled syringe. A planned interim analysis was conducted when the first 220 participants reached week 52. The trial also includes an open-label extension period of 52 weeks for participants who completed the 52-week treatment period.
The reduction in disease activity in TULIP-SC was measured using the British Isles Lupus Assessment Group based Composite Lupus Assessment (BICLA) at week 52. The BICLA requires improvement in all organs with disease activity at baseline with no new flares.
Clinical Expert Perspectives
Susan Manzi, MD, MPH, Professor of Medicine and Chair of the Medicine Institute at Allegheny Health Network, Professor of Medicine at Drexel University College, Philadelphia and principal investigator of the TULIP-SC trial, said: "Today's results for subcutaneous anifrolumab reinforce the efficacy and safety of this therapy and provide the opportunity for this important biologic to reach a wider group of patients in a more flexible and convenient way. Despite guidelines recommending earlier intervention and biologic treatments, too many people with systemic lupus erythematosus rely on oral corticosteroids, which contribute to irreversible organ damage."
Sharon Barr, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: "Today's news takes us one step closer in making the clinically meaningful benefits of Saphnelo accessible for more patients with systemic lupus erythematosus. The TULIP-SC results are especially important because approximately half of systemic lupus erythematosus patients today taking a biologic are already treated with a self-administered subcutaneous option. With Saphnelo, we hope to establish remission as an achievable treatment goal for more patients and we are actively working with regulatory authorities to bring this new administration option to patients as soon as possible."
About Saphnelo
Saphnelo (anifrolumab) is a first-in-class, fully human monoclonal antibody that binds to subunit 1 of the type I interferon (IFN) receptor, blocking the activity of type I IFN. Type I IFNs, such as IFN-alpha, IFN-beta and IFN-kappa, are cytokines involved in regulating the inflammatory pathways implicated in SLE.
Saphnelo IV infusion is approved for the treatment of moderate to severe SLE in more than 70 countries worldwide including the US, EU and Japan with regulatory reviews ongoing in other countries. To date, more than 38,000 patients globally have been treated with Saphnelo.
Next Steps and Broader Development Program
The TULIP-SC interim results are under regulatory review and will be presented during the American College of Rheumatology (ACR) Convergence 2025 annual meeting, 24-29 October 2025.
Saphnelo continues to be evaluated in diseases where type I IFN plays a key role, including Phase III trials in cutaneous lupus erythematosus, myositis, systemic sclerosis and lupus nephritis.
