Biogen (BIIB) has finalized its acquisition of Apellis Pharmaceuticals, marking the end of Apellis's tenure as a publicly traded company on the Nasdaq. The deal, valued at $41 per share in cash, closed on May 14 after Biogen accepted 82.4% of the outstanding shares tendered. Apellis (APLS) is now a wholly owned subsidiary of Biogen, and its shares have ceased trading.
Deal Details and CVR
Under the terms of the merger, each Apellis shareholder received $41 in cash plus one contingent value right (CVR). The CVR is not a traded security and is non-transferable except in rare circumstances. It could pay up to $4 per right if Syfovre, a key Apellis drug for geographic atrophy, meets specific annual net sales targets: $1.5 billion in any year from 2027 to 2030, or $2 billion through 2031. The maximum payout is only achievable in certain scenarios by 2031.
Market Reaction and Strategy
Apellis shares last traded at $41.03, slightly above the cash portion of the deal. Biogen shares closed at $192.95 on Friday. The acquisition is part of Biogen's broader transformation strategy under CEO Christopher Viehbacher, who noted the deal "immediately advances Biogen's ongoing transformation." Analysts, including BMO Capital's Evan Seigerman, viewed the purchase as a reset move that could "meaningfully change" market perception of Biogen's near-term revenue.
Portfolio Integration
Biogen gains two marketed drugs from Apellis: Syfovre for geographic atrophy associated with age-related macular degeneration, and Empaveli/Aspaveli, a complement therapy for rare kidney and blood diseases. Complement therapies modulate the immune system to prevent tissue damage. Biogen reported $689 million in net product revenue from these drugs in 2025 and plans to update its financial guidance with second-quarter results in July.
Competitive Landscape
Astellas Pharma, a competitor in the eye-drug market with its drug Izervay, announced on May 15 that China's drug regulator accepted its new drug application for avacincaptad pegol and granted Priority Review. This keeps global sales in play for the geographic atrophy treatment market.
Outlook for Shareholders
For former Apellis shareholders, the focus now shifts to Biogen's ability to deliver on the growth it paid for. The CVR remains a speculative element, with potential payouts dependent on Syfovre's commercial success. Biogen's stock performance will be the key indicator for those tracking the acquired assets going forward.
