Many dangerous and chronic diseases, such as cancer, rheumatoid arthritis, Crohn's disease, and psoriasis, can now be effectively managed thanks to biological medications. The availability of these life-saving medications for a larger patient population has been improved, and healthcare costs have decreased, thanks to biosimilar versions of biological treatments.
You'll hear more about this medicine class and the “interchangeability” label that some biosimilars obtain as they flood the market in more significant quantities. Here are the top five interchangeability-related facts you should be aware of.
1. Interchangeability is a further regulatory classification that applies to some biosimilars.
If allowed by state legislation, a biosimilar with an “interchangeable” designation can be used in place of its reference product at the pharmacy without further authorization from the prescribing physician. Sounds recognizable? This is comparable to how a pharmacist can complete a prescription by substituting a generic drug for a branded one.
Clinical studies must show, in contrast to therapy with only the reference product, that there is no increased risk or diminished pharmacological efficacy if a patient alternates between an interchangeable biosimilar and a reference product to receive the interchangeable designation.
To achieve the strict FDA standards for biosimilar safety and efficacy, switching studies are done in addition to the rigorous approval procedure that all biosimilars must undergo.
2. Regarding biosimilars, interchangeability is still the exception rather than the rule.
The Biologics Price Competition and Innovation Act (BPCIA), passed in 2010, permitted an interchangeability designation for FDA-approved biosimilars that complied with additional criteria.
As of October 2022, three biosimilars had received interchangeability status:
- An insulin product6.
- A drug used to treat certain inflammatory diseases.
- Treatment for retinal patients.
Eventually, there may be more. Other pharmaceutical companies have submitted applications seeking interchangeability status for biosimilars to a biologic medicine used to treat certain inflammatory conditions.
3. Only biosimilars are given an interchangeability designation in the United States.
Although the market for prescription drugs is seeing one of the most significant growth rates, interchangeability in real-world settings is still in its infancy. As a result, different countries have varied legal approaches. For instance, the United States has established a separate regulatory designation for interchangeability.
In the European Union, which introduced and embraced biosimilars before the United States did, it is up to each member state to decide whether to permit interchangeability for biosimilars. Additionally, interchangeability is not a distinct designation in Iran or Japan; instead, it is automatically implemented upon the approval of the biosimilar. Similarly, there may be differences in the regulatory evaluation criteria for biosimilars.
4. Even though interchangeability is permitted at the federal level, state rules still apply.
The FDA grants biosimilars and interchangeability designation on a federal level, but local drug dispensing and substitution at the pharmacy level are subject to state restrictions. With varying degrees of notice to the prescribing physician and the patient, most states permit the substitution of biosimilars for biologic medications. As of May 2019, 45 conditions permit the replacement of a biologic drug with a biosimilar.
5. The importance of interchangeability for medications prescribed by pharmacists
Typically, biologics (including biosimilars) are given intravenously or via injection. A healthcare provider often offers biological medications that are provided intravenously. At the same time, those administered by injection are typically dispensed from a pharmacy and may be self-administered.
Therefore, a reference product may be replaced with an interchangeable biosimilar for patients who receive their biologic from an online pharmacy, potentially saving money.
