On August 27, 2015, the U.S. Food and Drug Administration (FDA) released long-awaited and highly anticipated draft guidance regarding the non-proprietary naming of biological products, including biosimilars. The draft guidance was unexpectedly accompanied by a proposed rule in which FDA announced its intent to apply the proposed non-proprietary nomenclature scheme to six currently licensed biological products that are referenced by approved or publicly announced pending biosimilar applications, a product related to one of those reference products, or an approved biosimilar.

Key principles articulated in the draft guidance and/or proposed rule include:

• FDA will assign biological products proper (i.e., non-proprietary) names that include (1) a core name and (2) a four lowercase-letter suffix attached to the core name with a hyphen. The proposed nomenclature scheme is intended to clearly identify biological products to improve pharmacovigilance, and, for the purposes of safe use, to clearly differentiate among biological products that have not been determined to be interchangeable.

  • For “originator” biological products, FDA intends to assign a core name that is the name adopted by the U.S. Adopted Names Council (USAN) for the drug substance (when available). An “originator” biological product is one that is the subject of a Biologics License Application (BLA) approved under Section 351(a) of the Public Health Service Act (i.e., as a “stand-alone  BLA”) for which there is no previously licensed biological product licensed under a stand-alone BLA that is a “related” biological product.

  • For “related,” biosimilar, or interchangeable biological products, FDA intends to assign a core name that is the name of the drug substance contained in the relevant previously licensed product. A “related” biological product is one that is licensed as a stand-alone BLA for which there is a previously licensed biological product submitted in a different stand-alone BLA that contains a drug substance for which certain nomenclature conventions (e.g., USAN would be expected to provide for use of the same drug substance name. The use of a shared core name is intended to indicate a relationship among the products.

  • For originator, related and biosimilar biological products, FDA intends to assign a unique suffix. For interchangeable products, FDA is considering whether the suffix should be distinct from or shared with the reference product. The FDA proposes that, in all cases, the suffix be four lowercase letters, unique and devoid of meaning. Moreover, the FDA notes that the suffix should not be promotional; include abbreviations commonly used in clinical practice; contain or suggest any drug substance name or core name designated by the USAN Council; look similar to or be mistaken for the name of a currently marketed product; or be too similar to any other product’s suffix designation. The placement of the identifier as a suffix should result in biological products with the same core name being grouped together to help health care providers identify these products. If the naming convention is first applied to a new product, the request for FDA’s review of the preferred suffix should occur during the investigational new drug (IND) phase or at the time of BLA submission. For BLA holders seeking to propose a distinguishing suffix after BLA approval, the FDA recommends that a prior-approval labeling supplemental application be submitted. An applicant should submit no more than three proposed suffixes, in the order of the applicant’s preference. FDA will notify applicants of the suitability of the proposed suffix upon completion of the agency’s evaluation. Once approved, the FDA expects that manufacturers will implement the new proper name at the time of their next manufacturing run and does not intend to object to manufacturers exhausting existing inventories of finished product not labeled with the new proper name.

• The FDA intends to apply this naming convention to all biological products licensed—including products previously licensed—under Section 351(a) or 351(k) of the Public Health Service Act. For previously licensed products, the revised proper name would generally be the product’s original proper name plus the designated suffix. The FDA is considering the most effective regulatory approach to implement this naming convention for previously licensed products, but, in the near-term, intends to assign distinguishing suffixes to a limited group of products that are referenced by approved or publicly announced pending biosimilar applications (filgrastim, epoetin alfa, infliximab, pegfilgrastim), any related products to those reference products (tbo-filgrastim), or approved biosimilar product (filgrastim-sndz) through rulemaking. The proposed revised proper name for each product is summarized in the following table:

In the Federal Register notice that announced the availability of the draft guidance, the agency also posed several questions on which it specifically requests public comment (the following questions are reprinted from the Federal Register):

• What are the potential benefits and challenges of designating a suffix in the proper name of a biological product that is:

  • Devoid of meaning versus meaningful (e.g., a suffix derived from the name of the license holder)

  • Unique to each biological product versus unique to each license holder and shared by each biological product manufactured by that license hold
    In your comments, please address how each option would impact the following: Safe use of biological products; pharmacovigilance; and market acceptance and uptake for certain products.

• What would be the potential benefits and challenges for an interchangeable product to share the same suffix as designated in the proper name of the reference product? Your response should consider that FDA's publicly available electronic resource, the Purple Book, will identify biological products determined by FDA to be biosimilar to or interchangeable with a reference product. If an interchangeable product does share the same suffix as the reference product, how would this impact your responses to question 1, including pharmacovigilance?

• Would there be additional benefits or challenges if the suffix designated in the proper name of a biosimilar product that is subsequently determined to be interchangeable were changed to that of the reference product upon a determination of interchangeability? Would there be benefits or challenges to allowing the manufacturer of the biosimilar product that is subsequently determined to be interchangeable to have the option of retaining its original suffix or adopting the same suffix as the reference product?

• How could FDA and/or other Federal partners improve active pharmacovigilance systems for purposes of monitoring the safety of biological products? For example, because NDC numbers are not routinely recorded in billing and patient records in many clinical settings in which biological products are dispensed and administered, are there other identifiers besides distinguishable nonproprietary names that are routinely accessible by active pharmacovigilance systems and could enable as good as or better pharmacovigilance? How can FDA and/or other Federal partners help ensure that distinguishable identifier for each biological product would be captured at the point of dispensing or administration to the patient and be routinely accessible in systems used for pharmacovigilance?

• What process and reasonable timeframe should FDA use to designate a suffix to include in the nonproprietary name of a previously licensed biological product?

• What criteria should FDA use to prioritize retrospective application of this naming convention to previously licensed biological products?

• What are the expected time frames for sponsors of previously licensed biological products to distribute products that conform to this naming convention after approval of a labeling supplement?

• What strategies could FDA use to enhance stakeholders' understanding of and education about this naming convention?

• FDA notes that this naming convention (i.e., use of a suffix) has some similarities to the World Health Organization (WHO) proposal, "Biological Qualifier—An INN Proposal." At the time of publication of this draft guidance, WHO was still evaluating the comments received on its proposal. If WHO adopts a Biological Qualifier proposal, how should the biological qualifiers generated by WHO be considered in the determination of FDA designated proper names for the biological products within the scope of this guidance?

Interested stakeholders should submit comments regarding the draft guidance by October 27, 2015, and on the proposed rule by November 12, 2015.

Implications

Non-proprietary naming for biological—and, in particular, biosimilar—products has been a hot-button issue since Congress’ created the biosimilar approval pathway in March 2010. Manufacturers for reference biological products have urged FDA to establish unique non-proprietary names for biosimilars, arguing that distinct names are required to facilitate pharmacovigilance and avoid prescriber confusion. Companies developing biosimilars, however, have argued that such concerns are overstated and that the request for distinct naming is primarily intended to serve as a barrier to market uptake of biosimilars.

When the FDA approved its first (and, to date, only) biosimilar earlier this year (Zarxio™), it assigned the product a non-proprietary name comprised of the reference product’s non-proprietary name (filgrastim) and a suffix that identified the product’s manufacturer. Although the agency explicitly stated that the name was a placeholder, and not necessarily indicative of its position with respect to biological naming in general, the assigned name suggested that the FDA believed the reference product manufacturers had the stronger of the two arguments. The draft guidance lends further support to this hypothesis, as the agency now proposes to add a unique suffix to the non-proprietary name for all originator, related and biosimilar biological products. The agency is presently unsure how to proceed with respect to biological products that are determined to be interchangeable with a reference product, however, and has specifically requested comments on this issue.  

Although reference product manufacturers will generally be pleased with the proposal for unique non-proprietary names, the draft guidance’s proposal that the unique suffixes be “devoid of meaning” is likely to cause concern, as it is unclear that a non-memorable suffix would have the same uptake as a meaningful suffix (e.g., a suffix based on the manufacturer’s name). The FDA has specifically requested comments on this issue as well, however, so interested parties still have ample opportunity to influence the agency’s policy.