On March 6, 2015, the U.S. Food and Drug Administration (FDA) approved Sandoz Inc.’s (Sandoz) Zarxio as the first biosimilar product for use in the U.S.  Specifically, the FDA found Zarxio biosimilar to Amgen Inc.’s Neupogen® (filgrastim), which was originally licensed in 1991.  Zarxio is approved for the same indications as Neupogen® and can be prescribed by a health care professional for:

  1. Patients with cancer receiving myelosuppressive chemotherapy;
  2. Patients with acute myeloid leukemia receiving induction or consolidation chemotherapy;
  3. Patients with cancer undergoing bone marrow transplantation;
  4. Patients undergoing autologous peripheral blood progenitor cell collection and therapy; and
  5. Patients with severe chronic neutropenia.

The FDA’s approval of Zarxio was 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 demonstrated Zarxio to be biosimilar to Neupogen®.  Zarxio has been approved as biosimilar and not as an interchangeable product.

Interestingly, because the FDA has not yet issued a guidance on how current and future biological products marketed in the U.S. should be named, the FDA designated a placeholder nonproprietary name for Zarxio as “filgrastim-sndz.”  According to the FDA, this “placeholder” nonproprietary name should “not be viewed as reflective of the agency’s decision on a comprehensive naming policy for biosimilar and other biological products”.

Express Scripts Holding Co., the largest pharmacy benefit manager in the U.S., estimates that Zarxio will save the U.S. health-care system approximately $5.7 billion in the next 10 years assuming the product will be 30 percent cheaper than Neupogen®.

The approval of Zarxio was received with a great deal of enthusiasm in the U.S.  For example, Ralph G. Neas, President and CEO of the Generic Pharmaceutical Association stated:

Today’s FDA approval of Zarxio (filgrastim-sndz), the first biosimilar medicine in the United States, heralds a new era for cancer patients and the American health care system, one where access to safe, affordable versions of lifesaving biologics will finally be a reality.  Consumers, employers, private insurers, taxpayers, state governments and federal programs all will benefit from the advent of biosimilars, as intended by the Biologics Price Competition and Innovation Act (BPCIA) that was enacted as part of the Affordable Care Act.

However, despite the excitement generated by this approval, it is likely going to be some time until Zarxio is commercially available.  Specifically, Amgen has asked a federal judge in California for an injunction to block the launch of Zarxio, claiming Novartis did not follow the rules in seeking regulatory approval of the product.  A hearing is set for March 13, 2015 to consider the request.  Additionally, Novartis has agreed to delay the launch of Zarxio in the U.S. until the court issues a decision or until April 10, 2015, whichever is earlier.