Earlier this month, the FDA announced the first approval of a biosimilar product under the Biologics Price Competition and Innovation Act (BPCIA).  The new Sandoz product, which will be sold under the trade name Zarxio, is a biosimilar of Amgen’s Neupogen (filgrastim) product.  The FDA has, however, held off on releasing a naming policy for biosimilars, giving the product a “placeholder nonproprietary name” of “filgrastim-sndz.”  The FDA has stated that this placeholder name “should not be viewed as reflective of the agency’s decision on a comprehensive naming policy for biosimilar and other biological products” and that the agency intends to issue naming guidance in the “near future.”

The long-awaited guidance has broad implications for the healthcare industry.  The BPCIA is silent on the nomenclature to be used by the FDA on approved biosimilars.  In the world of chemical drugs, branded and generic drugs share the same nonproprietary name, also known as an International Nonproprietary Name (INN).  For small molecule drugs, the generic product has an identical chemical structure as the branded drug.  The purpose of this shared name is to allow healthcare practitioners to safely identify and prescribe chemically-identical branded and generic drugs to their patients.  Biosimilar products, however, are more complex.  While biosimilars are required to be “highly similar to the reference product” with no “clinically meaningful” differences (42 U.S.C. §262(i)(2)), they are different from the branded drug.

Some groups have argued that these differences require that biosimilars be granted different nonproprietary names to account for variations among different drugs.  One advocacy group claims that “unique naming provides transparency that supports confidence in, and ultimately utilization of, these new medicines as well as critical post-market surveillance and tracking.”  To that end, a number of groups have called for a naming policy that uses the current nonproprietary name associated with the branded drug and modified with a prefix or a suffix, as the FDA’s current “placeholder” name reflects.  Doing so, they suggest, will allow tracking of various biosimilars to ensure safety and quality.

Generic drugmakers, however, have argued that biosimilars should follow the FDA’s current naming convention for small molecule drugs and that unique nonproprietary names are unnecessary. Unique names, or names with different prefixes or suffixes, could give healthcare practitioners the idea that biosimilars have a different clinical effect from the original biologic drug.  They claim that such an impression would be incorrect, as the entire purpose of regulatory biosimilar approval is to ensure that the biosimilar has analogous effects.

An August 2014 letter from five U.S. Senators indicated that FDA regulators had drafted naming guidance and were awaiting clearance from the Department of Health and Human Services before releasing it for stakeholder comment.  The senators requested that HHS Secretary Sylvia Mathews Burwell “immediately release” any pending guidance.  To date, no such guidance has been released, but with more biosimilar applications in the pipeline, industry observers will be looking for additional FDA guidance soon.