Two of the Senate's highest-ranking legislators on healthcare issues are calling on the Department of Health and Human Services to finish its review of a guidance document on the naming of biosimilar products drafted by the US Food and Drug Administration (FDA).
In the US, the Patient Protection and Affordable Care Act (PPACA) of 2010 first created the pathway by which biosimilars—sometimes referred to as follow-on biologics or similar biological medicines—could come to market. The intent was to create a pathway similar to the one used by generic manufacturers of chemical drugs, offering companies a quicker and cheaper way to bring a product to market by being able to rely in part on the clinical data of the original manufacturer.
Unlike chemical drugs, manufacturing biological products is a vastly more difficult and complex process whose outcome is highly contingent upon the exact steps, equipment and manufacturing variables involved.
Crucially, even minor differences in the final protein structure can result in a product that behaves differently than the original, necessitating far more extensive testing requirements for biosimilars relative to generic drug products.
And because biosimilar manufacturers don't have access to any information regarding the processes by which the original drug is manufactured—that information is a trade secret—it is almost a foregone conclusion that the biosimilar product will be different from the original as well.
FDA Weighs In, If Only Briefly
But even as various issues related to biosimilarity continue to be debated in state legislatures and regulatory circles, one of the fiercest debates has been over the issue of what to call biosimilar products.
Because FDA requires generic drug products to be "bioequivalent" to the original drug, they are able to freely share the nonproprietary name for the product. For example, all generic forms of Tylenol are able to call themselves acetaminophen.
But as we noted earlier, biosimilar products aren't identical to the original products. In fact, FDA's latest biosimilars guidance, Clinical Pharmacology Data to Support a Demonstration of Biosimilarity to a Reference Product, only contains four levels of similarity:
- not similar
- highly similar
- highly similar with a fingerprint-like similarity
Even the fourth category, "fingerprint-like similarity," isn't quite the same as "identical."
So with that in mind, should a biosimilar product—for example, Humira (adalimumab)—be able to call itself by the same nonproprietary name (adalimumab), or should it be required to go by a new name entirely? Or, alternately, should biosimilar products be required to have a suffix (e.g. –Bsim)?
Not a Semantics Issue
For regulators, the naming issue isn't about semantics—it's about balancing accessibility with safety.
A September 2012 report by the Alliance for Safe Biologic Medicines (ASBM), a group supported by many biologics manufacturers, argued that non-unique names could lead to confusion between product types, making it more difficult to report adverse events to FDA. The same report also noted that biologics of the same name would infer interchangeability, even if the drugs are simply "similar," per FDA determination, and not "highly similar with a fingerprint-like similarity."
And some patient groups, such as the National Organization for Rare Diseases (NORD), have said that biosimilars should have distinguishable names so as to reduce physician and patient confusion about the drugs.
The Federal Trade Commission (FTC) is also looking into the issue, and held public workshops last year to explore how "naming conventions may impact the development of, and competition for, follow-on biologics."
Meanwhile, generic pharmaceutical groups, such as the Generic Pharmaceutical Association (GPhA), have noted the safety of biosimilar products used in the EU, where they have been approved for use for almost a decade, lessening the need for unique names.
Other Regulators Weigh In
Other regulators have recently begun to weigh in on the issue, most notably the World Health Organization (WHO), which has proposed a "biological qualifier" system meant to preserve the original biologic name, but require biosimilars to add a unique four-letter random code.
This, the WHO said, would allow healthcare systems, doctors and patients to differentiate between products, even as it also creates an expectation that the products are indeed similar.
But absent from the debate thus far has been FDA, which has yet to release any guidance on the naming issue. The agency has gone on the record saying it would prefer to have its biosimilar naming guidance released before it approves its first biosimilar application, and on 24 July 2014 announced that it had accepted a 351(k) (biosimilar) application for Sandoz's Zarzio, a biosimilar Neupogen (filgrastim).
The agency is also under pressure from industry, which has filed Citizen Petitions in an attempt to force the issue to the forefront.
Where's FDA's Naming Guidance?
Now two of the Senate's top healthcare legislators, Lamar Alexander (R-TN) and Orrin Hatch (R-UT), are calling for the release of FDA's biosimilar naming guidance—just not from the expected source.
And, according to Alexander and Hatch, the Department of Health and Human Services is now delaying the release of the biosimilar naming rule.
"It is our understanding that FDA has forwarded the naming guidance to the Department of Health and Human Services (HHS), and this guidance is awaiting HHS’ clearance so it can be released for stakeholder comment," the legislators wrote. "In order to ensure the success of the biosimilar pathway, it is imperative that the scientific experts at FDA maintain the autonomy to implement the pathway as intended in a manner that puts the safety of patients first."
"We urge you and those within your Department to immediately release guidance pending within the HHS related to the implementation of the biosimilar pathway," they wrote in their letter to HHS Secretary Sylvia Burwell.
Differences in opinion, the senators added, make the release of the guidance "even more important."
"The public needs to have time to comment and FDA time to revise the policies set forth in this draft guidance if necessary."
A previous version of this article misattributed the recipient of the senators' letter. It was Sylvia Burwell, who is now the Secretary of the Department of Health and Human Services (DHHS)—not, as we reported, the Office of Management and Budget (OMB), where she recently served as Director. We apologize for the error.
Alexander/Hatch Letter to HHS