Biosimilars in the United States: Current Status and Future Implications

Biosimilars in the United States: Current Status and Future Implications


Press Release

December 17, 2020
1 min read

FDA approves Riabni, third biosimilar to Rituxan


Press Release

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

The FDA approved rituximab-arrx for multiple indications.

The approval of rituximab-arrx (Riabni, Amgen) — the third biosimilar to rituximab (Rituxan; Genentech, Biogen) — applies to use of the agent for treatment of specific groups of adults with non-Hodgkin lymphoma, chronic lymphocytic leukemia, granulomatosis with polyangiitis and microscopic polyangiitis.

Rituximab-arrx is a CD20-directed cytolytic antibody.

“The approval of Riabni represents an important milestone across our biosimilar and oncology portfolios,” Murdo Gordon, executive vice president of global commercial operations at Amgen, said in a company-issued press release. “Riabni reaffirms Amgen’s long-term commitment to providing high-quality biosimilars that can potentially offer more affordable, effective treatment options for cancer and other serious diseases and that contribute to the sustainability of healthcare systems.

Biosimilars are biological products that have been shown to be highly similar to an already-approved biological product. The pre-approved agents are called reference products.

Biosimilars must have no clinically meaningful differences from their reference products with regard to effectiveness or safety. Only small differences in clinically inactive components are allowable with biosimilar products.

A randomized, double-blind comparative clinical study evaluated the efficacy, safety, pharmacokinetics and pharmacodynamics of rituximab-arrx for patients with grade 1 through grade 3A follicular B-cell non-Hodgkin lymphoma and low tumor burden.

Researchers randomly assigned 256 patients 1:1 to rituximab-arrx or Rituxan dosed at 375 mg/m2 via IV once weekly for 4 weeks, followed by dosing at week 12 and week 20.

Overall response rate by week 28 served as the primary endpoint.

Results showed the ORR with rituximab-arrx was within the prespecified margin to demonstrate clinical equivalence with Rituxan. Safety, pharmacokinetics, pharmacodynamics and immunogenicity also appeared similar.

The list price for rituximab-arrx in the United States will be $716.80 per 100 mg, or $3,584 for a 500-mg single-dose vial. This is 23.7% lower than the list price of its reference product, according to an Amgen press release.