On May 28, 2024, the FDA approved Amgen’s Bkemv™ (eculizumab-aeeb) as the first biosimilar for Alexion’s Soliris®, a complement inhibitor. The biosimilar was approved as interchangeable and for the following indications:
- Paroxysmal nocturnal hemoglobinuria (PNH) to reduce hemolysis
- Atypical hemolytic uremic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy
Bkemv, like the reference product Soliris, has a black box warning for the elevated risk of serious and life-threatening meningococcal infections caused by Neisseria meningitidis.
Both PNH and aHUS are considered rare diseases, which also makes this the only biosimilar approved specifically for the treatment of rare diseases. For example, PNH affects fewer than 6 people per million population. However, this does not necessarily mean that Soliris is not an attractive biosimilar target.
Astra Zeneca, which owns Alexion, reported 2023 US revenues of Soliris of $1.7 billion, a decrease of 23% from 2022. Much of this decrease can be attributed to the company’s increasing sales of Ultomiris®, a similar compound with a longer duration between administrations (4 or 8 weeks). In contrast, the originator compound is infused intravenously weekly at first, then biweekly. This product is infused by a healthcare provider and likely be covered under the medical benefit, as is the reference product. Therefore, the interchangeability designation serves little purpose, as the biosimilar will not likely be subject to automatic substitution through a pharmacy.
According to a 2020 patent settlement with Alexion, Amgen may launch Bkemv by March 1, 2025. The only publicly disclosed competition for Amgen’s Bkemv may be Samsung Bioepis’ SB12, which is approved in the EU. Samsung Bioepis filed for FDA approval for this candidate in July 2023, and a decision is expected in the third or fourth quarter of this year.
