Biogen Pursues Acquisition of Rare Disease Biotech Worth 7 Trillion Won

On March 31, Apellis Pharmaceuticals, Inc. (NASDAQ: APLS) announced that its principal shareholders entered into a tender and support agreement with Biogen Inc. (NASDAQ: BIIB) and its subsidiaries. Under the agreement, these shareholders will tender all of their Apellis common shares into Biogen’s proposed cash tender offer, vote in favor of the merger proposal and vote against any competing acquisition proposals.

They have also agreed to grant Biogen voting rights on certain merger-related matters and, aside from limited exceptions, to restrictions on transferring their shares, thereby endorsing both the tender offer and the merger agreement.

In a merger agreement signed the same day, Biogen will acquire Apellis for $41 in cash per share plus a contingent value right (CVR) of up to $4 per share based on future sales performance, valuing the transaction at approximately $5.6 billion (about ₩7.5 trillion).

Through this acquisition, Biogen seeks to integrate Apellis’s commercial assets—SYFOVRE, its treatment for geographic atrophy secondary to age-related macular degeneration, and EMPAVELI, its therapy for autoimmune and rare blood disorders—to expand its immunology and rare disease portfolio.

Headquartered in Waltham, Massachusetts, Apellis is a commercial-stage biopharmaceutical company targeting high-unmet-need diseases. Its lead products, SYFOVRE and EMPAVELI, selectively inhibit complement component 3 (C3) of the immune system to address geographic atrophy and paroxysmal nocturnal hemoglobinuria, respectively.

This deal underscores a broader trend in the U.S. biotech sector: large pharmaceutical companies are pursuing M&A to quickly bolster their rare disease and immunology pipelines, while smaller biotechs increasingly opt for strategic exits at the commercialization stage.