Biogen has finalized its acquisition of Apellis Pharmaceuticals, marking the end of APLS shares on the Nasdaq exchange. The deal, valued at approximately $5.6 billion, provides Apellis investors with $41 in cash per share along with a contingent value right (CVR) tied to future sales of Syfovre, the company's treatment for geographic atrophy, an advanced form of dry age-related macular degeneration.
According to a final tender offer update, approximately 105.7 million shares, or 82.4% of Apellis' outstanding stock, were tendered before the offer expired on May 13. Biogen's acquisition subsidiary accepted these shares for payment on May 14, completing the transaction. Following the close, Apellis shares ceased trading on Nasdaq, though some market screens still display a stale quote of $41.03 from May 14, reflecting the halt rather than current market activity.
Biogen's stock saw a modest gain of 0.9% on Wednesday, trading at $192.34 in early U.S. trading. The acquisition is expected to bolster Biogen's pipeline and revenue streams, particularly through Syfovre and Empaveli, which together generated $689 million in net product revenue in 2025. Analysts project these drugs could see mid-to-high teens growth through at least 2028.
CVR Details and Syfovre Sales Targets
The CVR component of the deal offers potential additional payouts based on Syfovre's performance. According to an Apellis filing, each CVR could pay $2 if Syfovre achieves at least $1.5 billion in annual global net sales in certain years, and an additional $2 if it reaches $2 billion. If these milestones are not met on schedule, there is a pathway that could lead to a maximum $4 payout by 2031. However, the filing also notes that there is no guarantee of hitting any CVR milestone, leaving the possibility that former Apellis shareholders may only receive the upfront cash portion of the deal.
In the first quarter of 2026, Apellis reported $192 million in U.S. net product sales from its two drugs, with Syfovre contributing $150.7 million and Empaveli adding $41.3 million. This breakdown underscores the heavy reliance on Syfovre for the CVR's potential value, as the drug must significantly scale up its sales to trigger the additional payments.
Strategic Implications for Biogen
Biogen CEO Christopher Viehbacher described the acquisition as a move that "immediately advances Biogen's transformation," highlighting the value of Apellis' nephrology platform, which will be leveraged for felzartamab, a Phase 3 kidney candidate. In an interview with Reuters, Viehbacher emphasized the "intrinsic value" of the kidney franchise, noting it as a key driver for the deal. BMO Capital analyst Evan Seigerman commented that the acquisition "could meaningfully change how investors think about near-term revenue growth" amid declining multiple sclerosis sales at Biogen.
The competitive landscape in the geographic atrophy segment remains intense. Astellas, which markets Izervay for the same condition, recently announced plans to share long-term Izervay results and new investigational data at the ARVO conference. The company describes geographic atrophy as a progressive disease that can cause irreversible vision loss, highlighting the importance of effective treatments.
Outlook and Risks
For former Apellis shareholders, the focus now shifts entirely to Biogen's ability to drive Syfovre sales toward the CVR targets. Risks include potential sales shortfalls, increased competition, or changes in physician prescribing patterns that could limit injection rates. Biogen is expected to update its financial guidance when it reports second-quarter earnings in July, providing the next key update on the integration and Syfovre's performance.
