Industry is calling on the US Food and Drug Administration (FDA) to use to use "meaningful" and "distinguishable" suffixes linked to a biosimilar license holder's name, according to comments on the proposed naming system.
In total, FDA received 178 comments on its draft guidance, known as Nonproprietary Naming of Biological Products, including clear calls for changes to FDA's proposal.
In August, FDA released the guidance, which proposed a naming convention to distinguish biological products through the use of a randomly assigned unique four letter suffix following the product's nonproprietary name.
Using FDA's example, a reference biologic could be assigned a suffix such as "replicamab-cznm," while a related biosimilar could be named "replicamab-hixf."
The agency said this system would "help prevent inadvertent substitution of biological products" and would support pharmacovigilance efforts for all biological products, ensuring biologics and related biosimilars are easily distinguishable.
The first biosimilar approved in the US, known commercially as Zarxio, uses the generic name filgrastim-sndz, with "sndz" representing the drug's manufacturer Sandoz, though the drug is not interchangeable with its reference product, Amgen's Neupogen.
When FDA released the draft guidance, the agency asked for feedback on whether products that demonstrate interchangeability should use the same suffix as their reference product, or if they should be given a unique suffix.
Industry, Patients and Health Care Practitioners
Industry groups such as the Biosimilars Forum, Biotechnology Industry Organization (BIO) and Pharmaceutical Research and Manufacturers of America (PhRMA) supported FDA's proposal, but called for the agency to use "meaningful" and "distinguishable" suffixes linked to the license holder's name.
The groups also felt products demonstrating interchangeability should be issued a unique identifier, rather than sharing an identifier with their reference product, saying this would reduce unintended switching and improve pharmacovigilance efforts.
Other organizations representing health care practitioners and patients agreed with this approach, including the American Society of Clinical Oncology, American Association of Clinical Endocrinologists, Alliance for Patient Access, Lupus and Allied Diseases Association, and Patients for Biologics Safety & Access.
Biosimilars Council and Insurers
However, the Generic Pharmaceutical Association's (GPhA) Biosimilars Council opposed FDA's proposal, claiming that "adding a suffix … is unnecessary and does not achieve the Agency's stated goals as it will lead to confusion among prescribers and patients." Their comment goes on to argue that these products "have other names … for distinct recognition; including a brand name, company name, a lot number and a national drug code (NDC) number that readily distinguish [them] from other products."
Insurers such as the Kaiser Foundation, CVS Health and America's Health Insurance Plans (AHIP) fell in line with the Biosimilars Council's stance, opposing the use of a suffix in favor of other measures to distinguish biosimilars for pharmacovigilance purposes.
Unlike many of the other organizations commenting on FDA's guidance, Public Citizen said it supports the use of a random suffix, and urged the agency to apply an identical suffix for interchangeable products.
The United States Pharmacopoeia (USP) called for FDA to include a suffix in the product label, rather than attaching a suffix to the product's nonproprietary name. USP argued that this approach would "facilitate a common global approach … consistent with existing, accepted scientific principles."
Federal Trade Commission
The Federal Trade Commission (FTC) came out against FDA's proposal on economic grounds, saying that "price competition is more intense when the products are seen as close substitutes for one another." The FTC also questioned whether FDA's proposal was necessary on pharmacovigilance and identification purposes, saying that "reliance on trade names may improve pharmacovigilance and prevent inadvertent substitution."
In its proposal, FDA also asked for input on how it should consider the World Health Organization's (WHO) existing proposal to issue a randomly generated four letter "biological qualifier" to all biological products.
Both BIO and PhRMA urged FDA to engage with WHO and other stakeholders in the future to discuss harmonization.
The FTC and USP favored WHO's approach, with the FTC saying "unlike FDA's proposed suffix, which would be part of the nonproprietary name, the [biological qualifier] would be separate from the nonproprietary name in pharmacy databases."