- The Food and Drug Administration clarified what its reviewers are looking for in order for biosimilars to win an interchangeable label, issuing a finalized guidance on Friday.
- An interchangeable designation will typically require a switching study, where patients move back-and-forth between the branded biologic product and the copycat.
- In a statement, FDA acting head Ned Sharpless also highlighted the possibility for interchangeable insulin biosimilars. The agency held a public hearing Monday on the future of these products for diabetics. March 2020 is when insulin biosimilars can begin to be approved.
None of the 19 biosimilars approved by the FDA have been deemed interchangeable, which would allow pharmacy substitution akin to how branded small molecule drugs are swapped out for generics.
The latest guidance spells out the rules for switching studies required to win such a lucrative label. Post-marketing surveillance could help shape the size of those trials, but is unlikely to be a replacement for such a test, according to the guidance.
The FDA's advice could instill confidence in all approved biosimilars, as it can show physicians and patients that interchangeability can be a study away for biosimilars already on the market, said Stacie Ropka, a partner at Axinn, Veltrop & Harkrider.
"The guidance could be seen as providing more comfort to patients and MDs in using biosimilars in general," Ropka said in an interview with BioPharma Dive. "They shouldn't be concerned about prescribing the biosimilar right off the bat because there's nothing in the guidance to suggest it's not going to work, and everything to suggest that it will work."
The impact on physician trust in biosimilars could play a significant role in driving U.S. uptake for these copycat medications. Last week, former FDA head Scott Gottlieb cited physician reluctance as a major impediment to the growth of the U.S. biosimilar market.
Ropka also highlighted the agency's recognition of advances in technology and analytics, which may help carve a future path to less burdensome studies.
In the FDA's language, the agency states that this "may in certain circumstances lead to a more selective and targeted approach to clinical studies intended to support a demonstration of interchangeability."
Drugmakers will need to decide between getting a biosimilar to market first before going for interchangeability, or if it makes more sense to go for interchangeability along with the initial regulatory submission.
One regulatory incentive that may drive these strategic decisions is the allure of market exclusivity for the first interchangeable. The first developer to secure an interchangeable license could have up to a year of market exclusivity from other copycats also gaining such a license, according to the law that established the biosimilar pathway.
More FDA guidance could be coming soon. Sharpless said future advice is coming from the agency on the design and evaluation of comparative analytical studies for biosimilars.