Biogen will acquire a drug company for $5.6 billion to expand work in kidney diseases

By Jaimy Lee

Biogen, already developing a drug that can be used to treat several kidney disorders, is paying a large premium for Apellis Pharmaceuticals

Biogen is buying Apellis for $5.6 billion in a deal that deepens its investment in the treatment of kidney diseases.

Biogen is spending $5.6 billion to buy Apellis Pharmaceuticals in a deal that aligns with its own strategy to bring to market a new treatment for people undergoing kidney transplants and suffering other kidney diseases.

Apellis has two approved drugs: Empaveli, which is approved to treat two rare kidney diseases, and Syforvre, which is used by patients with geographic atrophy, an advanced form of dry age-related macular degeneration. Both medicines brought in $689 million in sales last year.

Biogen, on the other hand, has been working on an experimental drug for several kidney diseases called felzartamab that it acquired in a 2024 deal. The experimental drug is currently in three late-stage clinical trials for kidney diseases, and Biogen believes that Apellis has the commercial infrastructure and talent to support that launch if felzartamab is approved.

"Consistent with our strategy, this acquisition immediately advances Biogen's ongoing transformation," Biogen CEO Christopher Viehbacher said in a news release.

Apellis's stock (APLS) soared 140% in premarket trades Tuesday, while Biogen's shares (BIIB) fell 4%.

Biogen is paying $41 per share, a large premium to Apellis's closing price of $17.09 on Monday, and Apellis shareholders can receive a contingent-value right for each of their Apellis shares. They would each get two payments of $2 per share based on Syfovre's achievement of sales targets. (Incorporating CVRs into deal terms has become increasingly popular in biopharma dealmaking.)

The deal is expected to close in the second quarter.

Biogen's stock is up about 5% so far this year, while the S&P 500 SPX is down 8%.

-Jaimy Lee

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