On August 27, 2015, FDA released a long-awaited draft guidance entitled “Nonproprietary Naming of Biological Products” (the “Draft Guidance”). The Draft Guidance sets forth a naming convention for all biological products – both those previously approved and those to be approved. Generally consistent with FDA’s approach in approving Zarxio® (filgrastim-sndz), the first biosimilar approved by FDA, the Draft Guidance adopts a middle-of-the road approach, providing that approved biologic products contain a four letter suffix following the USAN proper name.

Citing concerns of inadvertent switching and a need for improved pharmacovigilance, the Draft Guidance states that “shared nonproprietary names are not appropriate for all biological products.” In order to reduce prescribing errors, but still convey the message that biosimilars (and related biological products) are indeed similar to the reference product, the naming convention set forth in the Draft Guidance consists of a “proper name” for each licensed product that will be made up of a “core name” and a suffix. The “core name” is the name adopted by the USAN Council.  Biological products that are related, biosimilar, or interchangeable will have the same “core name” contained in the relevant previously licensed product.  Use of this “core name” “will indicate a relationship among products.”  The suffix for each product will consist of four lowercase letters that must be “devoid of meaning.”

The Draft Guidance elaborates that the suffix must not be promotional, include any commonly used medical abbreviations, contain any core name designated by USAN, look similar to any currently marketed product, or be too similar to any other product’s suffix designation.  As an example, the Draft Guidance suggests that two products sharing the “core name” replicamab may be designated as “replicamab-cznm” and “replicamab-hifx.”

Concomitant with the issuance of the Draft Guidance, FDA issued Proposed Rules designating official names and proper names for certain biological products. This proposed rule would redesignate Zarxio’s proper name from filgrastim-sndz to filgrastim-bflm, Teva’s previously licensed Granix® (tbo-filgrastim) would be redesignated filgrastim-vkzt, and Janssen’s Remicade® (infliximab – redesignated infliximab-hjmt), for example. The products in the list provided in the Proposed Rule are all subject to pending biosimilar applications. The preamble to the proposed rule mirrors FDA’s statements in the Draft Guidance.

FDA intends to apply the naming convention to interchangeable products.  However, the Draft Guidance solicits comments from stakeholders on whether interchangeable products should have the same prefix as the reference product.  Because, by definition, an interchangeable product produces the same clinical result in any given patient as the reference product and poses no additional risk in switching with the reference product, FDA’s concerns regarding immunogenicity and pharmacovigilance are minimized.  Accordingly, the Draft Guidance proposes two alternative options: (i) interchangeable products with suffixes distinct from the reference product; and (ii) interchangeable products with the same suffix as the reference product.  Input from stakeholders is requested.

Going forward, FDA expects that applicants will submit no more than three proposed suffixes during the IND phase or at the time of BLA submission.  The Draft Guidance suggests that the applicant include a supporting analysis of its proposed suffixes based on the factors set forth in the draft guidance.

It should be noted that FDA intends to apply the Draft Guidance for previously approved biologics.  In so doing, the Draft Guidance explains that consumers and health care professionals may inaccurately assume that a biological without a suffix (e.g., “filgrastim”) differs in clinically meaningful way from a biosimilar (e.g., “filgrastim-sndz).  FDA is still “considering the most effective regulatory approach to implement [the] naming convention for previously licensed products, including rulemaking, and will issue additional information.”  However, current sponsors should begin considering proposed suffixes for their currently licensed products.

FDA’s long awaited draft guidance is generally consistent with the approach taken in approving Zarxio® and adopts a middle ground position between innovator and generic interests.  Interested parties have seventy-five days to submit comments on the Draft Guidance.