FDA Approves New Rituximab Biosimilar & Anakinra to Treat a Rare Disease Michele B. Kaufman, PharmD, BCGP | February 2, 2021The FDA has approved anakinra to treat a rare autoinflammatory disease, deficiency of interleukin 1 receptor antagonist. The administration also approved a new rituximab biosimilar, Riabni, for multiple indications.