UPDATE 1-Biogen to buy Apellis Pharmaceuticals for $5.6 billion to expand its rare disease portfolio

Apellis Pharmaceuticals, Inc. -0.02%
Biogen Inc. +2.44%

Apellis Pharmaceuticals, Inc.

APLS

40.69

-0.02%

Biogen Inc.

BIIB

179.90

+2.44%

Adds shares in paragraph 4 , details throughout

- Biogen BIIB.O has agreed to acquire Apellis Pharmaceuticals for about $5.6 billion in cash, expanding its portfolio of rare-disease medicines, the companies said on Tuesday.

Under the terms of the deal, Apellis shareholders will receive $41 per share in cash, representing a premium of about 140% to the stock's last close.

They are also eligible to receive two payments of $2 per share each, contingent on certain global sales milestones for Apellis' eye disorder drug Syfovre, the companies said.

Shares of Apellis rose more than twofold in premarket trading.