Eva Tempkin

It has been a big fall for interchangeable biologics. President Biden’s Executive Order 14036, “Promoting Competition in the American Economy” directed the Department of Health and Human Services (and the Food and Drug Administration), and HHS subsequently published its “Comprehensive Plan for Addressing High Drug Prices.” Interchangeable biosimilars are front and center in both of these plans, as a key to stimulating competition in the market for biological products.

To that end, the HHS plan focuses FDA’s attention on increased clarity, transparency and flexibility for interchangeable biosimilars: directing FDA to issue guidance that adopts more flexible criteria regarding the data and information needed to support licensure and committing to continuing efforts to educate health care providers and patients about interchangeable biosimilars, among other things. For its part, FDA has promised, in its new round of user fee commitments, to publish numerous guidances on topics specific to interchangeability, including guidance on interchangeable presentations, container closure systems and device constituent parts, and guidance on interchangeable labeling.

Meanwhile, in late July, FDA approved the first interchangeable product, Semglee (insulin glargine-yfgn). As FDA noted in its press release, interchangeable Semglee is “both biosimilar to, and interchangeable with (can be substituted for), its reference product Lantus (insulin glargine).” FDA also listed interchangeable Semglee in the Purple Book, though it remains to be seen whether that listing resolves any of the confusion or adds to it. For example, the listing includes several insulin glargine products under the heading of “reference product,” even though Semglee is only approved as interchangeable with Lantus. And the Purple Book does not include a notation regarding which of Semglee’s two presentations, multi-use vial and autoinjector, is interchangeable with Lantus (the answer: both).

Only time will tell whether and how this first approval informs FDA’s practices going forward. We will see, for example, whether pharmacists are able to parse the Purple Book listings, or whether further refinements are needed. In the meantime, the questions posed in our original article persist. And, as noted in that article, there is (still) more work to be done to realize the promise of interchangeable products now that FDA has begun to approve them.

Eva Temkin is a partner in King & Spalding’s FDA & Life Sciences practice. She can be contacted at [email protected].