Double premium acquisition of Apellis (APLS.US) with $5.6 billion Biogen (BIIB.US) betting heavily on immunology and rare disease tracks.

Biogen Inc. (BIIB.US) has agreed to acquire Apellis Pharmaceuticals (APLS.US) for $5.6 billion, expanding its treatment portfolio in the fields of immunology and rare diseases, making it one of the largest acquisitions in the company's history. The Massachusetts-based biotechnology company will pay $41 per share for Apellis, a premium of over double the closing price on Monday. Apellis' stock price has dropped by 32% so far this year. In response to this news, Apellis' stock price has more than doubled in pre-market trading, while Biogen's stock price has fallen by approximately 1%. Through this deal, Biogen will gain access to two marketed drugs. Apellis' top-selling product is Syfovre, used to treat a major autoimmune disease that causes blindness, with revenues of $587 million last year. Another drug, Empaveli, is used for both a blood disease and a rare kidney disease, the latter of which has become a key focus area for Biogen. Last year, Empaveli had sales exceeding $100 million. As Biogen's multiple sclerosis business continues to decline and its Alzheimer's drug has had a slow start to market, CEO Chris Viehbacher has been seeking new areas of growth. Under Viehbacher's leadership, Biogen's largest deal so far was the $7.3 billion acquisition of Reata Pharmaceuticals in 2023, acquiring Skyclarys - the first drug approved to treat the rare neurological disease Friedreich's ataxia. The following year, Biogen acquired Human Immunology Biosciences for up to $1.8 billion, gaining access to a drug, felzartamab, currently undergoing testing for rare kidney diseases. In an interview, Viehbacher stated that this deal will bring immediate revenue growth to Biogen and aligns with the company's strategic direction. "We believe it has a high degree of synergies with the direction of our future pipeline," he said. Viehbacher expects the deal to be completed in the second quarter of this year. He revealed that Biogen has been researching Apellis for over a year, but "chose to wait for the right opportunity" because the company believed the market had previously overvalued Apellis. "We believe we paid a fair price for the company," he said. As part of the acquisition of Apellis, Biogen will gain access to the company's sales infrastructure to support the future launch of felzartamab after approval. Recently, Biogen has been focusing on early-stage research collaborations in the field of immunology, an area that has produced blockbuster drugs like AbbVie's arthritis treatment drug Humira.