Celltrion said its autoimmune disease treatment Zymfentra, the U.S. brand name for infliximab SC and the world’s only subcutaneous formulation of infliximab, recorded its highest-ever quarterly prescription volume this year.
According to Celltrion on Thursday, first-quarter prescriptions for Zymfentra surged 185% year over year, marking a record quarterly high.
The figure exceeded not only first-quarter prescriptions from last year but also the combined total for the entire first half of 2025. The company attributed the growth to the effectiveness of customized sales strategies implemented by its U.S. subsidiary.
Since launching Zymfentra in 2024, Celltrion USA has pursued a “3P” marketing strategy targeting key stakeholder groups with significant influence across the U.S. healthcare market: providers, payers and patients.
The top priority was physicians, who play a key role in prescribing the treatment. At the time of launch, Celltrion Group Chairman Seo Jung-jin and other executives traveled across the United States to meet directly with major physicians by region and disease area to promote the product.
The company also expanded its U.S. sales workforce to around 100 employees dedicated to Zymfentra, significantly strengthening its sales and marketing capabilities.
Securing reimbursement coverage through close coordination with insurers also contributed to the increase in prescriptions. In the U.S. healthcare market, where drug prices are high, products are effectively difficult to sell without reimbursement eligibility.
As a result, pharmacy benefit managers (PBMs) and insurers wield substantial influence in determining reimbursable medications. From the early stages of Zymfentra’s launch, Celltrion USA engaged with major PBMs, insurers and smaller firms, eventually securing reimbursement coverage for more than 90% of the insurance market.
Online and offline advertising campaigns targeting patients and the general public also played a key role in expanding prescriptions.
Celltrion USA has been running advertisements for Zymfentra across television, YouTube and social media platforms, while also promoting the treatment through hospital advertising campaigns aimed directly at patients.
The company expects Zymfentra’s growth momentum to continue in the second half of the year, citing several positive factors including reimbursement coverage exceeding 90%, increasing awareness among physicians and patients, and record prescription growth every quarter since launch.
Other high-margin products newly launched alongside Zymfentra are also performing well in the U.S. market. Steqeyma (ustekinumab), launched in March last year, secured a 10.2% market share within one year, placing it among the leading biosimilar prescriptions.
Meanwhile, Avtozma (tocilizumab) and Stoboclo-Osenvelt (denosumab), launched in the second half of last year, successfully secured reimbursement coverage through formulary agreements with major PBMs.
Celltrion also plans to launch additional high-margin products in the U.S. market later this year, including a subcutaneous formulation of Avtozma and Omlyclo, supporting expectations for continued earnings growth.
A Celltrion official said, “The fact that Zymfentra continues to break quarterly prescription records demonstrates that the customized sales strategies targeting key stakeholder groups are proving effective,” adding, “Given the upward prescription trend heading into the second half, growth is expected to accelerate further.”
Zymfentra clinical data unveiled at U.S. gastroenterology conference
Separately, Celltrion recently participated in the 2026 Digestive Disease Week (DDW) conference held in Chicago, where it presented clinical data for CT-P13 SC, marketed in the U.S. as Zymfentra and internationally as Remsima SC.
The company operated a dedicated booth to promote its brand competitiveness and also delivered two poster presentations.
On the opening day of the conference, Celltrion unveiled for the first time the 44-week results of a Phase 3 clinical trial conducted in Japan involving patients with Crohn’s disease who received CT-P13 SC.
The findings drew significant attention from medical professionals, showing that patients who had achieved clinical remission with the intravenous (IV) formulation maintained strong tolerability and safety after switching to the subcutaneous version.
The company also presented a post-hoc analysis of a 102-week global Phase 3 trial involving patients with Crohn’s disease and ulcerative colitis. The study showed that patients who received CT-P13 SC 240 mg after discontinuing IV treatment and receiving placebo for at least 16 weeks experienced rapid recovery in clinical response and sustained benefits through week 102.