Biogen has agreed to acquire Apellis Pharmaceuticals in an all-cash transaction valued at approximately USD 5.6 billion, plus contingent value rights (CVRs) linked to future sales of the drug Syfovre (pegcetacoplan). The acquisition provides Biogen with two marketed C3 complement inhibitors: Syfovre for geographic atrophy, and Empaveli (pegcetacoplan) for rare kidney diseases and paroxysmal nocturnal hemoglobinuria. Together, these products generated USD 689 million in net sales in 2025.

The deal aligns with Biogen's strategy to expand its immunology and rare disease portfolio. Apellis' established US commercial infrastructure, particularly in nephrology, is expected to bolster Biogen's upcoming launch of felzartamab, a candidate in Phase III trials for kidney diseases. Following the acquisition, Apellis employees will join Biogen, while the collaboration with Swedish Orphan Biovitrum (Sobi) for ex-US commercialisation of Empaveli will continue. The transaction is anticipated to close during Q2 2026.

According to PharmCube's NextBiopharm® database, only three complement-targeting M&A deals have taken place so far. Click here to request a free trial for NextBiopharm®.