Sandoz, a Novartis Group company, announced on July 24, 2014 that the US Food and Drug Administration (FDA) has accepted for review its application for a biosimilar version of filgrastim. The reference product, Neupogen®, which brought maker Amgen Inc. $1.4 billion in sales in 2013, is a biologic used to prevent
infections in cancer patients getting certain treatments that result in a decrease in infection-fighting white blood cells. Sandoz’s application for filgrastim is the first biosimilar application known to have been accepted by the FDA for review since the Biologics Price Competition and Innovation Act (BPCIA) established an approval pathway for biosimilars in 2009. Sandoz’s biosimilar filgrastim has already been approved in more than 40 countries outside the US under the brand name Zarzio®, including in Japan and Europe, and could be the first biosimilar approved in the US under the BPCIA. Such biosimilars could offer patients more affordable alternatives to existing biologic medicines similar to the way that generic drugs approved under the Hatch Waxman Act offer patients more affordable alternatives to their brand-name counterparts.
Sandoz’s announcement came shortly after the FDA released its draft guidance for industry entitled “Clinical Pharmacology Data to Support a Demonstration of Biosimilarity to a Reference Product.” The FDA had previously released three draft guidance documents outlining the FDA’s then-current thinking on important scientific and regulatory considerations relevant to submitting biosimilar applications, however, none of the industry guidance documents have yet been finalized. More importantly, none of the guidance documents provide clarity on the evidentiary thresholds required by the FDA to obtain interchangeability status for a biosimilar, which is required before an approved biosimilar can be substituted for a prescribed biologic without first consulting the prescribing physician. Although it is unclear whether Sandoz is pursuing interchangeability status for its biosimilar version of fligrastim, the FDA’s review of Sandoz’s application could provide much needed clarity on this as well as other issues related to the approval pathway for biosimilars. As the FDA weighs approval of Sandoz’s application, drugmakers are certain to gain insights on how the FDA will review future biosimilar applications.