On 15 September 2026, Celltrion announced that it has filed an Investigational New Drug (IND) application with the FDA for a Phase 4 clinical trial of high-dose (240 mg) Zymfentra™ (SC infliximab), biosimilar to Janssen’s Remicade® (IV infliximab).
The trial aims to demonstrate non-inferiority by comparing high dose intravenous infliximab with high dose Zymfentra™, a subcutaneous formulation, in patients with Crohn’s disease and ulcerative colitis. On successful completion of the study, Celltrion plans to offer a high dose Zymfentra™ option in the US, in addition to its 120 mg formulation.
This strategy mirrors a high dose strategy already being pursued by Celltrion in Europe, where Celltrion’s infliximab product is known as Remsima SC™. According to Celltrion, the strategy has helped Remsima SC™ gain approximately 32% EU market share.
Celltrion has also disclosed that it is conducting global clinical trials to expand the indications for Zymfentra™ to include rheumatoid arthritis.
Zymfentra™ (120 mg) was the first subcutaneous formulation of infliximab approved by the FDA for ulcerative colitis and Crohn’s disease in October 2023. It was launched in the US in February 2024.