Image: Biogen

Wednesday, May 27, 2026

Biogen completes acquisition of Apellis Pharmaceuticals

Biogen has completed its acquisition of Apellis Pharmaceuticals. Apellis is now a wholly owned Biogen subsidiary, and Apellis shares have stopped trading on Nasdaq.

The deal adds two marketed products to Biogen’s portfolio: SYFOVRE (pegcetacoplan) for geographic atrophy (GA) secondary to age-related macular degeneration, and EMPAVELI (pegcetacoplan) for complement-driven diseases including paroxysmal nocturnal hemoglobinuria (PNH) and certain rare kidney conditions. Combined, the products generated net product revenue of $689 million in 2025.

Transaction terms and closing mechanics

Under the tender offer, Biogen offered $41 per share in cash plus a contractual, non-transferable contingent value right (CVR) per share. The CVR provides for potential additional cash payments of up to $4 in total if specified annual global net sales thresholds for SYFOVRE are achieved.

Biogen said approximately 105,687,831 shares were tendered, representing about 82.4% of outstanding Apellis shares at the expiration time. After conditions were satisfied or waived, a Biogen subsidiary accepted the tendered shares for payment, and the transaction was completed via a merger under Delaware law.

Strategic focus: nephrology expansion

Biogen expects the acquisition to strengthen its near-term growth outlook and support its expansion into nephrology. Apellis also contributes an established nephrology commercial and medical infrastructure intended to support Biogen’s launch readiness for felzartamab. A first Phase 3 readout in antibody-mediated rejection in kidney transplant patients is anticipated in the first half of 2027.

Outlook and guidance

Biogen expects the transaction to be accretive to its non-GAAP diluted EPS in 2027. Updated financial guidance is expected alongside the company’s second-quarter earnings report in July.