The US Food and Drug Administration published its final guidance on biosimilar naming on January 12. Although nonbinding on the agency, this document seems to establish the FDA’s previous nomenclature decisions—which attaches a meaningless 4-letter suffix to all biosimilar and biologic products—as policy. Several questions still remain, however.
First, the FDA’s designation of the first US approved biosimilar—Zarxio® (filgrastrim-sndz)—is clearly at odds with this guidance. Will the agency decide to rename it? Last May, the FDA offered that it would rename it to filgrastim-bflm. At the time, it also suggested that it would add a “jcwp” suffix to Amgen’s originator product, and change tbo-filgrastim (Granix®) to filgrastim-vkzt. If so, it would seem that it will give Sandoz the opportunity to submit a list of preferred names. In any case, this would likely confuse payers’ claims systems for some time.
Second, the FDA left open its options in naming a product that it may designate as interchangeable. According to the guidance, “FDA is continuing to consider the appropriate suffix format for interchangeable products.” This is open to much speculation, although neither has the FDA issued its final guidance for approving a product as an interchangeable biosimilar (and will not do so until at least December 2017) nor has a manufacturer publicized its willingness to seek the interchangeable designation.
Third, although the FDA has decided that it will assign suffixes to previously approved biologics, including the reference products, “the revised proper name of biological products previously licensed under the PHS Act generally would include the product’s original proper name serving as the core name plus the distinguishing suffix attached with a hyphen. [The agency] is continuing to consider the process for implementation of this naming convention for previously licensed products but, in the near term, intends to assign distinguishing suffixes to a limited group of these products and also will accept submissions of prior approval labeling supplements that include proposed suffixes.” There seems to be no timetable for implementation of this considerable effort.
In addition, the FDA has reestablished its support for manufacturers, suggesting up to 10 preferred suffixes at the time of 351(k) or 351(a) application. The agency will then make a choice based on the suggestions and how well they meet the basic criteria set out by FDA.