Pfizer announced on February 25 that the Food and Drug Administration had accepted a supplemental 351(k) application for its adalimumab biosimilar Abrilada™, in an attempt to gain the interchangeability designation. This is just one development in clarifying the upcoming adalimumab interchangeability competition.
This press release was posted just before Alvotech’s announcement that the FDA had accepted Alvotech’s biologic license application for its own interchangeable adalimumab biosimilar AVT02. Iceland-based Alvotech had originally filed the 351(k) application in late summer 2021; however, the FDA took no action until February. This would potentially give Alvotech an FDA decision in late Q4. Supplemental BLA’s are usually processed faster, and Pfizer may hear back as early as October 2022.

The timing is a bit less important, unless Alvotech decides to launch immediately upon approval (Alvotech has not yet signed an agreement with AbbVie, which could dictate its launch date). This would put AVT02 ahead of Amgen’s Amjevita®, which will launch in January 2023. Pfizer will launch its product no earlier than July 2023, per their agreements with AbbVie. Boehringer Ingelheim’s Cyltezo®, the first autoimmune product designated interchangeable by the FDA, will also launch in the July 2023 timeframe.
In both Pfizer and Alvotech’s cases, they conducted studies that involved multiple switches between their respective biosimilars and the reference product in patients with rheumatoid arthritis. So far, the only differentiating characteristic among these three products, should interchangeability be approved for all, is that Alvotech offers a high-dose concentration. They will all be available in citrate-free versions. Amgen is currently performing a multi-switching study, in the hopes of obtaining the designation late 2023 or early in 2024. With multiple interchangeable adalimumab biosimilars to be launched, one fact still remains—these products may be automatically switched at the pharmacy for the reference product only, not for each other. Despite the multiple switches conducted as a requirement for the FDA’s designation, they have not been studied against each other. Therefore, the interchangeability designation may only have value in the first year or two of marketing, putting a bit of a damper on the adalimumab interchangeability competition.