Last reviewed 2026-04-22 · How we verify

Yisaipu®

Yisaipu is a recombinant human TNF receptor II-IgG fusion protein that binds and neutralizes tumor necrosis factor (TNF) to reduce inflammatory responses.

Yisaipu is a recombinant human TNF receptor II-IgG fusion protein that binds and neutralizes tumor necrosis factor (TNF) to reduce inflammatory responses. Used for Rheumatoid arthritis, Ankylosing spondylitis.

At a glance

Mechanism of action

The drug functions as a TNF inhibitor by acting as a soluble TNF receptor that captures circulating TNF-α and TNF-β, preventing their interaction with cell surface TNF receptors. This mechanism suppresses the inflammatory cascade driven by TNF, making it useful in TNF-mediated inflammatory and autoimmune conditions. It is structurally similar to etanercept, another TNF receptor fusion protein.

Approved indications

• Rheumatoid arthritis
• Ankylosing spondylitis

Common side effects

• Infection (including serious infections)
• Injection site reactions
• Upper respiratory tract infection

Key clinical trials

• Real-World Study on Long-term Treatment With YISAIPU for Fujian RA Patients
• Treatment of Axial Spondyloarthritis by Recombinant Human Tumor Necrosis Factor-α Receptor Ⅱ IgG Fc Fusion Protein (PHASE4)
• A Study of the MASEI in the Treatment of Anti-TNF Blocker to Peripheral Tendonitis in Patients With Spondyloarthritis (PHASE4)
• Sequential Application of Yisaipu® and DMARDs in Treating Mild-to-Moderate AS (PHASE4)

Primary sources

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