Posted 05 June 2014
By Alexander Gaffney, RAC
Ever since the US passed into law a new regulatory pathway in 2010 meant to permit the US Food and Drug Administration (FDA) to approve so-called "biosimilar products"—effectively generic biological products that differ slightly from the original product—one of the fiercest debates surrounding their use has also been one of the simplest: What do you call them?
Now a prominent patient advocacy group has weighed in with its own thoughts, arguing that its prime concern is about patient safety.
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.
The Naming Debate
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)?
Is it About Safety? Or Trade?
To some, the issue is about far more than just aesthetics or encouraging consumer confidence.
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."
The Federal Trade Commission (FTC) is also looking into the issue, holding 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.
NORD Weighs In
Now, yet another group has thrown its hat into the biosimilar naming debate.
The National Organization for Rare Diseases (NORD), a prominent patient advocacy group, has written to the US Food and Drug Administration (FDA) advocating for the adoption of "distinguishable names for biologics, including biosimilars."
"Our position stems from the existing lack of consistent naming protocols for biologics and the potential for significant physician and patient confusion once biosimilars become available," the group wrote in the letter, which is addressed to FDA Commissioner Margaret Hamburg. "Distinguishable names for biologics support the medical community’s vital post-approval learning curve about which medicines are best for their rare disease patients."
They cited the need for health care providers to know that their patients have received exactly the medication that they prescribed, something they said would be much easier if the biosimilar products have their own names, allowing their health outcomes to be tracked and studied more easily.
While NORD said it, and the patients it represents, welcome biosimilars due to the likelihood of a "substantial discount" in price relative to existing therapies, it argued that a lack of assurance that the similar products will work "the same as the reference product" in patients have led it to err on the side of caution. The move would also serve a reminder to healthcare professionals about the limits of biosimilar products and the methods of their approval (based on similarity, not equivalence).
NORD Letter to FDA