‘Meaningless suffixes’ slammed by industry in FDA naming guidance

Pfizer and industry groups have criticised the US FDA over the randomness of a four-letter suffix demanded in the nonproprietary names of biological products.

First announced in an August 2015 draft, the US Food and Drug Administration (FDA) has stuck with its decision to add a “a distinguishing suffix that is devoid of meaning and composed of four lowercase letters” to the non-proprietary name of reference biologics and biosimilar products in final guidance published yesterday.

The Agency says such naming will “facilitate pharmacovigilance” for biological products “when other means to track a specific dispensed product are not readily accessible or available,” as well as facilitating “accurate identification of these biological products by health care practitioners and patients.”

“Further, distinguishing suffixes should help minimize inadvertent substitution of any such products that have not been determined to be interchangeable.”

“Disappointed with meaningless suffixes”

But Pfizer – which sells reference biologics and a biosimilar in the US – told Biopharma-Reporter that while it agrees biological products should have names readily distinguishable to facilitate tracking and to ensure appropriate prescribing and dispensing, but took issue with the randomness of the suffix.

Pfizer believes the suffix should be meaningful – derived from or in some way related to the license holder name – or a single random company-specific suffix that would become meaningful over time,” spokeswoman Rachel Hooper said.

Pfizer’s views were shared by nonprofit advocacy group The Biosimilars Forum – founded by ten biosimilar developers, including Pfizer – which said it too was “disappointed” in the decision to apply meaningless suffixes, as these “will certainly be more difficult for physicians and patients to recall than meaningful suffixes.”

“Additionally, they will likely lessen the ability to carefully track the identity of the biologic drug administered to patients, thereby contrary to the stated purpose of having a suffix to enhance pharmacovigilance.”

The ruling was also criticized by the physician group Alliance for Patient Access, funded by over 20 reference biologic developers, which said a memorable suffix “is the surest way for patients and providers to know which medication is being taken.”

Infliximab and filgrastim

Pfizer’s recently launched biosimilar Inflectra has been given the nonproprietary name’ infliximab-dyyb,’ while Amgen’s approved Humira biosimilar is known as ‘adalimumab-atto.’

However, Zarxio – the first biosimilar to be approved in the US – has the nonproprietary name ‘filgrastim-sndz’ which is quite clearly has a suffix which is not meaningless, referencing the marketing holder Sandoz.

While Sandoz did not comment on the final guidance at the time of going to press, it has told this publication previously it is against having any differentiator – meaningful or not – in the naming of biological products, as if an adverse event occurs a patient will use the brand name and not the INN to report the problem.

Our primary view is that no four-letter thing is needed for the INN but we haven’t been able to win that battle,” global head biopharmaceutical development Mark McCamish told us in June 2016. “I’d like to have it my way, but again my goal is to get things to patients so if it’s out there we will certainly comply.”

Changing names

And according to the FDA, ‘filgrastim-sndz’ is likely to undergo a name change to comply with the randomization ruling, though further guidance will be published to implement this.

“This guidance also will apply to those biological products that are approved under the Federal Food, Drug, and Cosmetic Act (FD&C Act) on or before March 23, 2020,” yesterday’s publication said.

“FDA intends to provide additional guidance regarding administrative issues associated with the transition (including the process for implementing the naming convention described in this guidance).”