Biogen paid $41 per share — plus a contingent value right worth up to $4 more — to take full ownership of Apellis, a company whose two commercialized products together generated $689 million in net revenue last year. That price implies Biogen is buying roughly 4x trailing revenue, a multiple that looks aggressive until you factor in what it actually purchased: not just a complement franchise, but a commercial nephrology infrastructure it would have taken years and hundreds of millions to build organically for felzartamab.
That infrastructure point is the real logic here, and it’s being underplayed. SYFOVRE and EMPAVELI are real assets — SYFOVRE is among the first approved therapies for geographic atrophy, a condition affecting more than five million people globally, and EMPAVELI holds a first-mover position in C3G and IC-MPGN — but Biogen already flagged felzartamab as a pipeline priority. A Phase 3 readout in antibody-mediated rejection is expected in the first half of 2027. Without the Apellis salesforce and nephrology medical infrastructure already in place, that launch window would have been a scramble. Now it isn’t.
The financial mechanics are straightforward but worth naming precisely: the deal is accretive to non-GAAP diluted EPS starting in 2027, not immediately. Biogen absorbs dilution for the balance of 2026 and is betting the complement revenue trajectory plus felzartamab launch upside erases that gap quickly enough to satisfy investors who have watched BIIB struggle to articulate a durable growth story post-aducanumab. The 82.4% tender participation rate — roughly 105.7 million shares — signals institutional shareholders were willing sellers at this price, which tells you something about how the market was valuing Apellis on a standalone basis.
The contingent value right tied to SYFOVRE sales thresholds is the real tell on deal confidence: Biogen essentially deferred up to $4 per share of the purchase price contingent on hitting annual net sales milestones it believes are achievable but didn’t want to pay for upfront. Watch SYFOVRE’s 2026 net revenue trajectory — specifically whether it crosses $500 million on its own — as the single clearest signal of whether this acquisition’s embedded assumptions hold.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
