Implications Of FDA's Biosimilar Naming Tweak For Manufacturers

By Anna Rose Welch, Editorial & Community Director, Advancing RNA

The FDA has slightly revised its guidance on biosimilar naming following a period industry comments. While the suffix will still be an integral part of a biosimilar’s name, it will no longer be randomly assigned by the FDA. Instead, the agency has granted biosimilar makers the opportunity to submit up to 10 suffixes for each new biosimilar and biologic, ranked in order of preference. This contrasts with the original proposal, in which the company was only permitted to submit up to three proposals for a random suffix.

In addition to the suggestions for suffix, in The Federal Register, the FDA “also recommend[s] including supporting analyses demonstrating that the proposed suffixes meet the factors described in the guidance for FDA’s consideration.” This specification suggests these suffixes must remain meaningless, as per the draft guidance.

Industry Response To Original Draft Guidance

Over the past few months, the FDA has received a number of comments and letters from industry members and organizations protesting the use of randomly assigned suffixes. According to many stakeholders, the random suffix would be difficult for physicians to remember and would stall the prescription and use of biosimilar medicines. Similarly, several parties argued that meaningful suffixes would better promote pharmacovigilance and patient safety. (And, as is to be expected, there were also comments arguing that the use of suffixes is unnecessary for pharmacovigilance, as has been witnessed in Europe where suffixes are not included in biosimilar names. However, the majority of comments received on the guidance were in support of using a suffix.)  

So far, the U.S. has seen two biosimilars approved, each boasting a different naming convention. Last September, Zarxio was launched with the international non-proprietary name filgrastim-sndz. In this case, the suffix pointed back to the drug’s manufacturer Sandoz. Meaningful suffixes, such as an abbreviation of the manufacturer’s name, was one possibility the FDA considered prior to its draft guidance. (There still are concerns however, that the use of this kind of meaningful suffix could grant certain manufacturers an advantage in the market.) However, following the release of the draft guidance specifying a random suffix, the FDA gave the nod to Inflectra, Celltrion’s and Pfizer’s Remicade biosimilar, or infliximab-dyyb.

Industry’s Concerns With New Proposal

One of the primary concerns so far with this change is the amount of time it will take for drugmakers to come up with possible suffixes, as well as how long it will take for the FDA to review these suggestions. The FDA expects it will receive 40 requests annually for the proposed proper name for biologics, and six for the proposed proper name of biosimilars. The FDA expects it would take sponsors roughly two hours on the submission of one suffix, or six hours for three suffixes. This was met with one comment in particular arguing that analyzing and selecting possible suffixes would take upwards of 720 hours per suffix, or 2,160 for three suffixes. However, because no information was provided on how this number was attained, the FDA does not expect this total would be broadly applicable to other manufacturers. The agency has, however, raised its estimate to account for the amount of time and energy it will take manufacturers to create and submit up to 10 proposed suffixes.

Overarching Implications Of This Change  

This move giving manufacturers the ability to create a larger number of suffixes is a small but important freedom. So far, the industry has been waiting for the FDA to make some key, market-shaping decisions — for instance, how interchangeability will play out. Compared to the European Medicines Agency (EMA), which has left it up to each country to determine interchangeability, the FDA is creating an organized, overarching decision on how a drug earns this status. This guidance will clearly specify what the manufacturer will need to do clinically and analytically in order to attain an interchangeability designation. So, to give drugmakers a greater say in creating their products’ suffixes gives the manufacturer more control in designating its product. This will be a key way to garner trust and recognition for its biosimilar against the reference drug. It could also serve as a way to free up some of the FDA’s bandwidth, which has been an industry concern as the FDA’s plate becomes more crowded with biosimilar programs.

However, this tweak does raise questions over how meaningful this naming system will become as drug makers are given more room to create options. For instance, will there end up being be a mix of random and meaningful suffixes on the market? If so, will companies find a way to make meaning out of “random” suffix? Will the FDA revise the guidance in the future to pay heed to the number of comments calling for more meaningful suffixes? In the end, the ability to create and prioritize a biosimilar suffix suggests that the ones at the top of the drugmaker’s list would have some kind of meaning for the drugmaker. (Chatter about this change on Twitter took a hilarious stab at some proposals that are NOT likely to make the FDA’s cut. Though perhaps someone ought to try it — the FDA could probably use a few laughs.)