Back in 2015, the FDA implemented a policy which required the addition of suffixes to biosimilars. On June 1 2016, the FDA suggested that sponsors could provide the FDA with up to 10 preferred proposed suffixes for its biosimilars and that the FDA would then choose which preferred suffix met its guidelines. Sounds like a good policy, right? Companies get to suggest their favorite “baby” names and the FDA picks one it likes. Well, the FDA withdrew that plan on June 20, 2016.
However the suffixes for biosimilars have been chosen since June 2016, it was clear that the FDA only applied this requirement for suffixes (which makes sense for biosimilars, so that consumers can tell them apart and doctors can report adverse events) to biosimilars. For example, Sandoz’s Zarxio’s nonproprietary name is “filgrastim-sndz”. Totally logical so far.
On November 16, 2017, the FDA approved Genetech’s hemophilia A biologic Hemlibra (good news for patients!) and assigned it a random suffix of “kxwh” (emicizumab-kxwh). In the absence of published public comments (which would be published in the Federal Register) and/or the announcement of a policy decision, one has to assume that assigning these suffixes to all new biologics will be the law of the land.
We know the time an effort industry sponsors put into branding their biologics and we imagine that random characters appended to the end of such a carefully-considered name is not the most welcome of surprises. The FDA typically provides sponsors with substantial notice prior to making substantive policy changes (it is a government agency after all!); however, this sort of abrupt implementation of policy may be our new normal.