WASHINGTON -- The FDA today for treatment of adults with CD20-positive B-cell non-Hodgkin lymphoma (NHL).
The approval allows for use of the biosimilar as a single agent or in combination with chemotherapy. The action followed a unanimous vote last month in support of approval by the FDA Oncologic Drugs Advisory Committee (ODAC).
"The Truxima approval is our third biosimilar approval in the past month," FDA Commissioner Scott Gottlieb, MD, said in a statement. "The growing pipeline of biosimilars is encouraging. We're seeing more biosimilar drugs gain market share as this industry matures. We'll continue to make sure biosimilar medications are evaluated efficiently through a process that makes certain that these new medicines meet the FDA's rigorous standards for approval."
The FDA approval covered the following indications for rituximab-abbs:
- Single-agent treatment of relapsed or refractory, low grade or follicular lymphoma
- Combination therapy for previously untreated follicular lymphoma, followed by single-agent maintenance for patients who achieve a partial or complete response
- Single-agent treatment of nonprogressing, low-grade, NHL after first-line chemotherapy
The FDA noted that rituximab-abbs received approval "as a biosimilar, not as an interchangeable product" for the original rituximab (Rituxan) made by Roche's Genentech unit. Also, the approval does not include a variety of other indications for which Rituxan is approved, including chronic lymphocytic leukemia, rheumatoid arthritis, pemphigus vulgaris, and certain polyangiiitis conditions.
Evidence submitted in support of the approval included extensive data on the composition, pharmacokinetics, and pharmacodynamics of the biosimilar product. Additionally, the ODAC panel reviewed findings from two randomized clinical trials comparing rituximab-abbs and Rituxan.
A trial involving 140 patients with advanced NHL resulted in response rates of 95.7% for the biosimilar and 90.0% for branded rituximab (both combined with chemotherapy), meeting statistical criteria for noninferiority. Confidence intervals did not rule out the possibility of superiority for the biosimilar. A 258-patient randomized trial of single-agent therapy resulted in response rates of 83.1% with the biosimilar and 81.3% with branded rituximab. In general, adverse event rates were similar between treatment groups in both of the two trials.
Authors of a FDA staff report concluded that rituximab-abbs "is highly similar to U.S.-licensed Rituxan, notwithstanding minor differences in clinically inactive compounds, and support a demonstration that there are no clinically meaningful differences between [the biosimilar] and U.S.-licensed Rituxan in terms of safety, purity, and potency of the product."