The US Food and Drug Administration (FDA) has approved Sandoz’s Zarxio (filgrastim-sndz), the first biosimilar product approved in the United States. The biosimilar is based on the reference product, Neupogen, marketed by Amgen, which was originally licensed in 1991.

Zarxio is approved for the same indications as Neupogen, and can be prescribed by a healthcare professional for: patients with cancer receiving myelosuppressive chemotherapy; patients with acute myeloid leukemia receiving induction or consolidation chemotherapy; patients with cancer undergoing bone marrow transplantation; patients undergoing autologous peripheral blood progenitor cell collection and therapy; and patients with severe chronic neutropenia.

The regulatory pathways for biosimilars was authorized by the Biologics Price Competition and Innovation Act of 2009 (BPCI Act), which was passed as part of the Affordable Care Act that was signed into law in March 2010. The BPCI Act created an abbreviated licensure pathway for biological products shown to be “biosimilar” to or “interchangeable” with an FDA-licensed biological product, called the “reference product.” This abbreviated licensure pathway under section 351(k) of the Public Health Service Act permits reliance on certain existing scientific knowledge about the safety and effectiveness of the reference product, and enables a biosimilar biological product to be licensed based on less than a full complement of product-specific preclinical and clinical data. A biosimilar product can only be approved by the FDA if it has the same mechanism(s) of action, route(s) of administration, dosage form(s) and strength(s) as the reference product, and only for the indication(s) and condition(s) of use that have been approved for the reference product. The facilities where biosimilars are manufactured must also meet the FDA's standards.

The FDA's approval of Zarxio is based on review of evidence that included structural and functional characterization, animal study data, human pharmacokinetic and pharmacodynamics data, clinical immunogenicity data and other clinical safety and effectiveness data that demonstrates Zarxio is biosimilar to Neupogen. Zarxio has been approved as biosimilar, not as an interchangeable product. Under the BPCI Act, a biological product that that has been approved as an “interchangeable” may be substituted for the reference product without the intervention of the health care provider who prescribed the reference product.

For this approval, the FDA has designated a placeholder nonproprietary name for this product as “filgrastim-sndz.” The provision of a placeholder nonproprietary name for this product should not be viewed as reflective of the agency's decision on a comprehensive naming policy for biosimilar and other biological products. While the FDA has not yet issued draft guidance on how current and future biological products marketed in the United States should be named, the agency intends to do so in the near future.

Sandoz is the generics arms of Novartis.Sandoz estimates that it has a 50% volume share of biosimilars approved in North America, Europe, Japan, and Australia. It currently markets three biosimilars (somatropin, filgrastim and epoetin alfa) outside the US. Marketed as Zarzio outside of the US, the Sandoz biosimilar filgrastim is available in more than 60 countries worldwide,The Sandoz pipeline also  has several biosimilars across the various stages of development, including five programs in Phase III clinical trials/filing preparation.

“The FDA approval of Zarxio marks a significant milestone for the United States healthcare system and for patients who might suffer from neutropenia,” said Carol Lynch, Global Head of Biopharmaceuticals & Oncology Injectables at Sandoz, in a company statement. “As the global leader in biosimilars, we are honored to be the first company to successfully work with FDA to navigate the US biosimilar pathway, and we look forward to making this high-quality biosimilar available to patients in the US.”

Source: FDA and Novartis