Apellis Pharmaceuticals, Inc. (APLS)

Apellis Pharmaceuticals, Inc. was a commercial-stage biopharmaceutical company focused on therapies that target C3, a central protein in the complement system, which is part of the body's innate immune defenses. The company was founded in 2009 and was led by co-founder and chief executive officer Cedric Francois. Its headquarters were in Waltham, Massachusetts, and it completed its initial public offering on Nasdaq in November 2017 under the ticker APLS.

The company's core molecule was pegcetacoplan, a C3 inhibitor. In May 2021 the U.S. FDA approved a systemic formulation, marketed as Empaveli, for paroxysmal nocturnal hemoglobinuria, a rare blood disorder. Apellis later obtained approval to expand its use into rare kidney diseases, and it partnered with Sobi for commercialization of the systemic product outside the United States.

In February 2023 the FDA approved an intravitreal formulation, Syfovre, as the first treatment for geographic atrophy secondary to age-related macular degeneration, a leading cause of vision loss. Syfovre became the main commercial driver for the company and was sold to retina specialists in the United States. Apellis also faced safety-related scrutiny from retina physicians after post-marketing reports of retinal inflammation, which it addressed through label updates and further data.

On the transaction, Biogen Inc. announced in the spring of 2026 that it would acquire Apellis for $41 in cash per share, together with one non-transferable contingent value right per share. The CVR could pay up to $4.00 in total, tied to global net sales milestones for Syfovre from 2027 through 2031. The upfront equity value was about $5.6 billion, excluding the CVRs, and the cash price represented a premium of roughly 140 percent to Apellis's closing price on March 30, 2026.

Biogen said the deal would add growth products in immunology and rare disease and extend its presence into nephrology. Apellis stockholders and regulators cleared the transaction, and Biogen completed the acquisition on May 14, 2026. At closing, Apellis common stock was removed from trading on Nasdaq, the company was deregistered from SEC reporting, and Apellis became a wholly owned subsidiary of Biogen.

Apellis also had outstanding convertible notes, and the merger triggered repurchase and conversion rights for noteholders as described in the company's notice. Certain noteholders also received the non-transferable CVRs. The ticker APLS no longer trades.