The U.S. Food and Drug Administration (FDA) has approved Pfizer‘s Ruxience (rituximab-pvvr), a biosimilar to Rituxan (rituximab), as a treatment for granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) — the two most common subtypes of ANCA-associated vasculitis, the company announced.
While allowing Ruxience’s use for ANCA vasculitis, the FDA also approved the biosimilar for five blood cancer indications, including for treatment of non-Hodgkin’s lymphoma and chronic lymphocytic leukemia. It is the second biosimilar to Rituxan to be approved in the U.S., after that of Truxima (rituximab-abbs), also for lymphoma, in November 2018.
“Biosimilars like Ruxience have the potential to deliver real value in healthcare, improving access to and affordability of an important cancer treatment which could help more patients receive optimal care,” Andy Schmeltz, global president of Pfizer Oncology, said in a press release.
Rituxan, developed by Genentech and Biogen, has been approved in the U.S. for the remission induction treatment of GPA and MPA since 2011. Its use was then extended in October 2018 to maintain remission in patients with these common types of vasculitis.
It is designed to target the CD20 protein at the surface of immune B-cells and lymphoma cells, tagging them for destruction.
The therapy works, but the cost of a 10-milliliter vial of Rituxan is around $1,000.
Researchers note that, when a medicine’s patent expires, other companies are allowed to produce similar medications, which often are sold at lower prices. Usually these similar medications are called generics. However, when it comes to biological products, the name is biosimilar.
Unlike chemical compounds, which are made through chemical reactions, biological medicines are grown in cells. They may show some differences from similarly designed products.
As a result, regulatory agencies require extensive data showing that a biosimilar has equivalent safety and effectiveness as the original medicine. The biosimilar also must be shown to behave similarly to the original medication, once in the body, with regard to absorption, distribution, metabolism, and excretion.
The FDA’s approval was based on extensive biochemical, preclinical, and clinical data demonstrating the similarity between the new antibody and the original, called its reference agent.
These data included results from the REFLECTIONS B328-06 Phase 3 study (NCT02213263). That clinical trial directly compared the activity and safety of Ruxience to that of Rituxan in adults with CD20-positive follicular lymphoma, a type of non-Hodgkin’s lymphoma for which Rituxan is approved.
In this study, 394 participants were randomly assigned to treatment with either Ruxience or Rituxan, given intravenously (into the vein) once a week. The data did not show clinically meaningful differences between the two antibodies, demonstrating similar safety and therapeutic activity.
“With this FDA approval, clinicians have an additional treatment option that will help improve access to care for patients in need of anti-CD20 mAb therapy,” said Jeff Sharman, MD, medical director of hematology research for U.S. Oncology.