FDA Approves Pfizer's Second Biosimilar Infliximab, Ixifi

Pfizer announced on December 13 that the FDA has approved Ixifi, PF-06438179, infliximab-qbtx, the company’s second biosimilar to the reference infliximab, Remicade.

Approval of the biosimilar follows acceptance of Ixifi’s Biologics License Application (BLA) in April 2017, and is based on the totality of evidence demonstrating a high degree of similarity to the reference Remicade. Pfizer’s BLA included data from the REFLECTIONS B537-02 study in patients with moderate to severe rheumatoid arthritis (RA).

The phase 3, multi-national, randomized, double-blind, 2-arm, parallel-group study evaluated the safety, efficacy, and immunogenicity of the biosimilar compared with the reference infliximab administered intravenously in combination with methotrexate. The study met its primary endpoint of achieving a response of ACR20—a 20% improvement by American College of Rheumatology criteria—at week 14. These findings were supported by additional data at week 30.

The FDA has approved Ixifi as a treatment for patients with RA, Crohn disease, pediatric Crohn disease, ulcerative colitis, ankylosing spondylitis, psoriatic arthritis, and plaque psoriasis.

Pfizer adds Ixifi to its portfolio of biosimilars, including Inflectra, the first FDA-approved biosimilar infliximab, as well as European Medicines Agency- (EMA) approved Retacrit (epoetin zeta), and EMA-approved Nivestim (filgrastim). However, a Pfizer representative told The Center for Biosimilars^® that the company does not plan to commercialize Ixifi in the United States. Pfizer will continue to market its first infliximab biosimilar, Inflectra, in the US market, said the representative, and the approval of Ixifi will not impact its strategy with Inflectra.

Inflectra has had a challenging experience in the US market; while Pfizer’s first FDA-approved infliximab biosimilar has launched in the United States, Johnson & Johnson’s strategies to protect its market share have led Pfizer to file suit against the reference product’s sponsor, claiming that anti-competitive practices have effectively denied patients access to lower-cost biosimilars.

Sandoz, which acquired the European rights to Ixifi in 2016, plans to develop and eventually commercialize the drug in the 28 EU member states as well as Iceland, Liechtenstein, and Norway.