CSPC Files for Secukinumab Biosimilar Marketing Approval, Accelerating Domestic Substitution in China's IL-17A Market

Biologics  ·  Autoimmune Disease

CSPC's biosimilar secukinumab filing marks another step in China's push to localize production of one of the world's best-selling antibody drugs, as the IL-17A franchise faces mounting generic pressure globally.

On June 17, China's Center for Drug Evaluation (CDE) confirmed it had formally accepted a marketing application from CSPC Jushi Biopharm for a secukinumab injection, according to the regulator's website. The filing, assigned acceptance number CXSS2600093, is classified as a Class 3.3 therapeutic biological product — China's regulatory designation for a biosimilar.

If approved, the product would become the latest domestic challenger to enter China's IL-17A inhibitor market, a segment anchored by Novartis AG's Cosentyx, one of the most commercially successful monoclonal antibodies of the past decade.

A proven target, a proven drug

Secukinumab is a fully human IgG1 monoclonal antibody that neutralizes interleukin-17A, a cytokine central to the inflammatory cascade in psoriasis, psoriatic arthritis, ankylosing spondylitis and related autoimmune conditions. Novartis's Cosentyx, the reference product, became the first IL-17A inhibitor to win global regulatory approval when it launched in 2015. Since then, it has accumulated indications spanning plaque psoriasis in adults and children aged six and older, active psoriatic arthritis, ankylosing spondylitis, non-radiographic axial spondyloarthritis and hidradenitis suppurativa.

Cosentyx entered the Chinese market in 2019 and has since been included in the National Reimbursement Drug List, broadening patient access. The drug has generated peak annual global sales approaching USD 5 billion, making it a cornerstone of Novartis's immunology franchise.

Head-to-head data, biosimilar pathway

CSPC's candidate, developed under the code name SYS6012, was evaluated under China's biosimilar regulatory framework, which requires demonstration of similarity to the reference product in quality, safety and efficacy. The company conducted a head-to-head comparative program comprising a Phase I pharmacokinetic study in healthy subjects and a Phase III equivalence trial in psoriasis patients — a multicenter, randomized, double-blind, parallel-group study with an active comparator.

In December 2025, CSPC, acting through its controlled subsidiary Sinobiology, disclosed top-line results from the Phase III study. According to the announcement, SYS6012 met its predefined equivalence endpoints, showing high similarity to Cosentyx across efficacy, safety, pharmacokinetic profile and immunogenicity.

Under China's biologics registration rules, a Class 3.3 approval may permit indication extrapolation, potentially allowing the biosimilar to cover the full range of indications already granted to the reference drug.

A Crowded, Fast-Moving Market

China's IL-17A inhibitor market is already taking shape as one of the more competitive biosimilar battlegrounds in the country's autoimmune space. The originator Cosentyx and Eli Lilly and Co.'s Taltz (ixekizumab) are both commercially available. Multiple domestic firms are advancing secukinumab biosimilars through late-stage clinical development, with CSPC among the front-runners.

CSPC Jushi Biopharm, the group's dedicated biologics platform, has built out a dense pipeline of antibody therapies in recent years. A secukinumab approval would add a marquee asset to its autoimmune portfolio and position the company to capture share in a market where cost pressure is rising alongside clinical demand.

The access argument

For patients living with chronic autoimmune diseases, the arrival of a domestic biosimilar carries a straightforward implication: lower out-of-pocket costs. Psoriasis alone affects an estimated 6.5 million people in China, with moderate-to-severe cases accounting for roughly 30% of that total. IL-17A inhibitors are now among the most widely prescribed biologic therapies for the condition, yet the long-term financial burden of treatment remains a significant barrier for many patients.

Industry observers note that as additional domestic secukinumab biosimilars reach the market, intensified competition is expected to drive down overall treatment costs, expanding access to biologic therapy for a broader patient population.

What comes next

With the CDE acceptance, CSPC's secukinumab injection now enters the formal technical review phase, which will include document evaluation and on-site manufacturing inspections. If the review proceeds without significant delays, approval could come within the next one to two years.

Meanwhile, several other Chinese developers are advancing their own secukinumab biosimilar programs, some already in late-stage clinical testing. Over the next few years, the IL-17A franchise in China is poised to undergo a structural shift as domestic products displace originator pricing power — a pattern that has already played out across oncology and metabolic disease categories in the country's rapidly evolving pharmaceutical market.

Information for this article was drawn from the CDE website, corporate announcements and publicly available regulatory filings.