FDA Guidance on Biosimilar Naming to Support Pharmacovigilance

After much speculation and debate, the US Food and Drug Administration (FDA) has released guidance for biologic and biosimilar product naming conventions. The regulator will require the addition of a four-letter, non-word suffix to the name of the drug’s active ingredient in order to differentiate between the biopharma products, and facilitate pharmacovigilance efforts.

Unlike generic drugs, biosimilars are not chemically-identical to their reference biologic, and therefore cannot be freely substituted. The new suffix rule was designed to help prevent pharmacists from inadvertently dispensing a biosimilar in place of the branded biologic.

As the FDA has so-far only approved four biosimilar drugs – Zarxio, Inflectra, Erelzi and Amjevita – it has already applied the naming convention of adding the four-letter suffix to the non-proprietary name of these products. For example, the non-proprietary name of Sandoz’ Zarxio is filgrastim-sndz. However, the FDA’s finalized guidance will require biologics makers to add a unique suffix to their drug products as well.

When the rule was still in review, pharmaceutical trade organizations including PhRMA and BIO urged the FDA to make the four-letter additions meaningful. They argued that suffixes based on the sponsor company’s name would be easier to remember, therefore potentially improving pharmacovigilance.

“PhRMA believes that adopting meaningful suffixes that are generally derived from that name of the sponsor or application holder will enhance prescriber recognition, use, and memory of suffixes and thus, the utility of suffixes for their pharmacovigilance and safety objectives,” PhRMA said in a comment to the FDA. “Suffixes that are “devoid of meaning” likely will prove difficult to remember and, as a result, are less likely to be used consistently throughout the healthcare delivery system.”

Unfortunately, PhRMA didn’t get their request, however the FDA plans on helping the industry by assigning suffixes to a selection of approved biologics. The agency is also working on implementing a process to encourage biopharma companies to adopt the naming convention.

These four-letter additions should help distinguish biologic and biosimilar drugs, and help pharmacovigilance teams track adverse events. As the number of biologics going off-patent continues to increase, the biosimilars market is expected to expand in the next few years.