Celltrion is accelerating clinical development of Zymfentra in the United States as it seeks to expand the drug’s prescribing options beyond its current 120mg dose.
The South Korean biopharmaceutical company said Tuesday that it has submitted an Investigational New Drug (IND) application to the U.S. Food and Drug Administration (FDA) for a Phase 4 study designed to establish clinical evidence for a 240mg dose of Zymfentra.
The trial will enroll 447 patients with Crohn’s disease or ulcerative colitis across 55 U.S. medical centers. Researchers will compare the 240mg subcutaneous formulation with high-dose intravenous infliximab, with the study primarily designed to assess non-inferiority.
Celltrion expects the study to generate additional evidence supporting dose selection based on disease severity and individual patient needs. If successful, the company could offer U.S. physicians a two-dose treatment approach combining the existing 120mg regimen with the higher 240mg option.
The strategy builds on experience with Remsima SC, the product marketed as Zymfentra in the U.S., in Europe. Celltrion said Remsima SC recorded an approximately 32% market share across the five major European markets during the first quarter of this year. The company attributes part of the product’s growth to treatment strategies tailored to patients’ disease severity.
Expanding dosing options is not the company’s only avenue for growth. Celltrion is also pursuing additional clinical development for rheumatoid arthritis (RA), seeking to broaden Zymfentra’s potential patient base beyond inflammatory bowel disease.
An RA indication could significantly expand the drug’s addressable market in the U.S., where autoimmune diseases represent a major segment of the biologics market. Celltrion expects a broader indication portfolio, combined with differentiated dosing options, to support longer-term growth.
Zymfentra has already posted strong commercial growth in the U.S. The drug generated 99.5 billion won ($approximately 72 million) in sales during the first half of the year, up 176.4% from a year earlier, according to Celltrion.
The company said Zymfentra has secured reimbursement coverage for more than 90% of insured patients in the U.S. Its local direct-sales network is also being used to strengthen relationships with healthcare providers and expand market access.
Industry analysts say competition in the U.S. biologics market is increasingly driven by more than clinical efficacy alone. Reimbursement access, prescribing convenience, differentiated dosing options and the ability to address a wider range of patients are becoming important factors in determining a product’s market penetration.
For Celltrion, securing clinical evidence for the 240mg regimen could therefore become an important component of its U.S. growth strategy. The company plans to combine expanded dosing options, potential new indications and its direct-sales infrastructure to strengthen Zymfentra’s position in the American autoimmune disease market.
A Celltrion official said the new study is expected to “expand treatment options tailored to individual patients” while further strengthening Zymfentra’s clinical value.
The company added that it will continue investing in clinical development and commercial capabilities to accelerate Zymfentra’s adoption and establish the drug as a key treatment option in the U.S. autoimmune disease market.
