New Biosimilar Approved for Multiple Conditions

FDA approves Riabni (rituximab-arrx), the third biosimilar to Rituxan (rituximab)

(RxWiki News) The US Food and Drug Administration (FDA) has approved a new biosimilar to Rituxan (rituximab) to treat several serious conditions.

Riabni (rituximab-arrx) is the third approved biosimilar to Rituxan. The FDA approved it to treat the following conditions in adults:

  • Non-Hodgkin's lymphoma (NHL)
  • Chronic lymphocytic leukemia (CLL)
  • Granulomatosis with polyangiitis (GPA) (Wegener's granulomatosis)
  • Microscopic polyangiitis (MPA)

A biosimilar is a biological product that is highly similar to another biological product that has already been approved. This already approved product is known as a reference product. And in this case, the reference product is Rituxan. The new biosimilar is Riabni.

Often, biosimilars can provide a different option that is less expensive. In some ways, biosimilars are like generic versions of biologic drugs. According to Healio, the projected list price of Riabni is almost 24 percent lower than the current US list price for Rituxan.

The FDA found no "clinically meaningful differences" between Riabni and Rituxan in terms of effectiveness or safety when treating the listed conditions, according to Amgen. (Amgen is the pharmaceutical company that plans to manufacture Riabni.)

Like its reference product, Riabni will come with some serious warnings about potential adverse events. These warnings, called boxed warnings, are the most serious side effect warnings a medication can receive. Boxed warnings for Riabni warn about the following potential adverse outcomes:

  • Potentially fatal infusion reactions
  • Hepatitis B virus reactivation
  • Potentially fatal mucocutaneous reactions (reactions of the skin and linings of body organs and cavities)
  • Progressive multifocal leukoencephalopathy (a rare and potentially fatal brain infection)

Less serious common adverse events included nausea, anemia, headache, diarrhea, fever, chills, muscle spasms, infection and reduced white blood cell count. This medication may also harm unborn babies.

Talk to your health care provider about the treatment options available for your condition.

Review Date: 
January 4, 2021