FDA Approves Biosimilar for Patients with Rheumatoid Arthritis

June 6, 2022
Kenny Walter

Kenny Walter is an editor with HCPLive. Prior to joining MJH Life Sciences in 2019, he worked as a digital reporter covering nanotechnology, life sciences, material science and more with R&D Magazine. He graduated with a degree in journalism from Temple University in 2008 and began his career as a local reporter for a chain of weekly newspapers based on the Jersey shore. When not working, he enjoys going to the beach and enjoying the shore in the summer and watching North Carolina Tar Heel basketball in the winter.

Rituximab-arrx is similar in safety and efficacy to rituximab for patients with moderate to severe rheumatoid arthritis.

The US Food and Drug Administration (FDA) has approved rituximab-arrx (RIABNI), a new biosimilar to rituximab (RITUXAN) for the treatment of adult patients with moderate to severe rheumatoid arthritis in combination with methotrexate.

The treatment is earmarked for patients who have not had an adequate response to 1 or more tumor necrosis factor (TNF) antagonist therapies.

The Biosimilar

Rituximab-arrx is a CD20-directed cytolytic antibiotic with no clinically meaningful differences in safety or efficacy to rituximab based on the data from a randomized, double-blind, comparative clinical study.

The biosimilar has been previously approved for the treatment of adult patients with Non-Hodgkin's Lymphoma (NHL), Chronic Lymphocytic Leukemia (CLL), Granulomatosis with Polyangiitis (GPA), and Microscopic Polyangiitis (MPA).

The Reasoning

In the trial, investigators compared the efficacy, safety, pharmacokinetics, and immunogenicity of rituximab-arrx and rituximab reference product in patients with moderate to severely active rheumatoid arthritis.

There were 311 patients included in the trial.

The investigators sought a primary efficacy endpoint of the change in disease activity score 28 using C-reactive protein DAS28-CRP) from baseline at week 24. The results were within the predefined equivalence margin showing equivalence in clinical efficacy between the 2 treatments. Safety, pharmacokinetics, and immunogenicity were also similar between the 2 treatments.


"The approval of RIABNI is an important advancement for adults living with moderate to severe rheumatoid arthritis, a chronic inflammatory joint disease, who now have access to a proven and affordable treatment option," said Murdo Gordon, executive vice president of Global Commercial Operations at Amgen, in a statement. “Our fully integrated portfolio of innovative and biosimilar medicines for inflammatory diseases reinforces our commitment to providing patients with high-quality and affordable treatment options that deliver substantial value to our healthcare system."