Biogen to Acquire Apellis for $5.6B Cash Plus CVRs, Boosting Immunology & Rare Disease Portfolio
BIIB sits 67% above its 52-week low of $110.035 on elevated volume (2.1× avg).
Summary
Biogen announced a definitive agreement to acquire Apellis Pharmaceuticals for approximately $5.6 billion in cash plus contingent value rights, significantly expanding its immunology and rare disease portfolio.
Key Events · M&A and Partnerships · BIIB
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Acquisition Agreement
Biogen will acquire Apellis Pharmaceuticals for approximately $5.6 billion in cash upfront through a tender offer, followed by a second-step merger.
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Contingent Value Rights (CVRs)
Apellis stockholders will receive one non-transferable CVR per share, potentially worth up to an aggregate of $4.00 in cash, contingent on SYFOVRE® annual global net sales milestones ($1.5B and $2.0B) through 2031.
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Strategic Expansion
The acquisition adds two commercialized immunology and rare disease products, EMPAVELI® and SYFOVRE®, to Biogen's portfolio, with combined 2025 net sales of $689 million, expected to grow at a mid-to-high teens rate through at least 2028.
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Financial Impact
The transaction is expected to be increasingly accretive to Biogen's non-GAAP diluted EPS starting in 2027 and significantly boost its non-GAAP EPS compounded annual growth rate through the end of the decade.
Analysis · BIIB · Life Sciences
This 8-K details Biogen's definitive agreement to acquire Apellis Pharmaceuticals, a significant strategic move valued at approximately $5.6 billion upfront, plus potential contingent value rights (CVRs) of up to $4.00 per share based on SYFOVRE® net sales milestones. The acquisition is expected to immediately enhance Biogen's growth profile by adding two commercialized immunology and rare disease medicines, EMPAVELI® and SYFOVRE®, which generated $689 million in combined net sales in 2025. This transaction is projected to be increasingly accretive to Biogen's non-GAAP diluted EPS starting in 2027 and accelerate its expansion into nephrology. The support from key Apellis insiders, who have agreed to tender their 14% stake, underscores confidence in the deal. Investors should monitor the integration process and the performance of the acquired assets, particularly SYFOVRE® sales, which will determine the CVR payouts.
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At the time of this filing, BIIB was trading at $183.33 on NASDAQ in the Life Sciences sector, with a market capitalization of approximately $26.9B. The 52-week trading range was $110.04 to $202.41. This filing was assessed with positive market sentiment and an importance score of 9 out of 10.