Biogen moved to cut most of its pipeline work after acquiring Apellis Pharmaceuticals for $5.6 billion, pausing or canceling investment across the majority of Apellis programs that came with the deal. The company also laid off a small number of employees tied to the restructuring. The spokesperson characterized the actions as part of rebalancing internal resources following the acquisition, effectively re-centering Biogen’s R&D priorities rather than carrying forward the full Apellis research slate. For Apellis and its collaborators, the decision signals execution risk around previously transferred assets and underscores how quickly large acquisitions can trigger portfolio compression.