Biogen, eyeing swift commercial tailwind, ponies up $5.6B for Apellis and its 2 approved meds

Despite a healthy roster of late-stage assets and a revenue turnaround in 2025, it’s no secret that Biogen has been seeking near-term sales drivers ahead of its planned product rollouts later in the decade. 

Now, the company is responding by bulking up in immunology—and paving the way for its future ambitions in kidney diseases—with an M&A play that adds two ongoing launches to its marketed drugs portfolio.

On Tuesday, Biogen unveiled a deal to acquire Apellis Pharmaceuticals for $41 per share in cash, representing a total transaction value of roughly $5.6 billion. For Biogen, the deal grants access to the approved Apellis meds Syfovre for the eye condition geographic atrophy (GA) and Empaveli, approved by the FDA last year in the rare kidney diseases complement 3 glomerulopathy (C3G) and primary immune complex membranoproliferative glomerulonephritis (IC-MPGN). 

Prior to that nod, Empaveli won its first U.S. approval in 2021 to treat paroxysmal nocturnal hemoglobinuria (PNH). 

Collectively, Apellis’ two marketed products generated $689 million in sales last year, according to Biogen’s March 31 press release. 

Under the arrangement, which is expected to close in the second quarter, Apellis investors will also receive a contingent value right (CVR) for each company share held. The CVR will be worth up to $4 per share, depending on certain sales thresholds for Apellis’ products being met, Biogen said. 

As it stands, Apellis—headquartered in Waltham, Massachusetts—boasts around 740 employees, with Biogen noting Tuesday that it expects a “significant portion” of Apellis staffers to join Biogen after being absorbed. Further, Biogen clarified that it will continue to work with Apellis’ partner, Sobi, on the commercialization of Empaveli outside the United States. 

Laying out the rationale behind the deal, Biogen CEO Chris Viehbacher told analysts Tuesday that he feels “great” about his company’s late-stage pipeline—which includes phase 3 assets across neurology, immunology and more—while admitting that those prospective drug launches aren’t likely to start chipping in toward growth until around 2028. 

Assessing nearer-term opportunities, Viehbacher said the company didn’t “want to take a lot of phase 3 risk,” instead hunting for a company with a product early in its launch or just about to make its market debut. 

Biogen did not want to “stretch our balance sheet” with a transaction either and wanted to find a target that it could acquire at a favorable price, the CEO said.  

“This is really an immunology play,” Viehbacher explained, adding that with the planned acquisition of Apellis, Biogen is likely done with significant M&A moves for the present. 

In the near-term, revenue from both Syfovre and Empaveli together is expected to grow in the mid- to high teens annually “for at least the next two years,” Biogen CFO Robin Kramer said on an analyst call Tuesday, adding that the company will adjust its 2026 guidance when it reports first-quarter earnings later this year. 

On Syfovre specifically, which generated $587 million in GA sales in 2025, the market the drug plays in is large, numbering roughly 1.5 million patients in the U.S., but still underpenetrated, Adam Keeney, Ph.D., Biogen’s head of corporate development, said on the call.

“We know that the market is competitive, but we’re also optimistic that best-in-class Syfovre, coupled with Biogen’s demonstrated U.S. capabilities and Apellis’ sales and marketing team, we can enable the product to realize its full potential,” he said. 

Syfovre’s chief complement inhibitor rival in the GA space is Astellas’ Izervay, first cleared by the FDA in 2023 before scoring a label expansion last year.

As for Empaveli, it’s early days for the drug’s launch in its two new kidney indications, and Biogen believes that it can leverage its commercial muscle for a boost here, too. Empaveli also offers a potential commercial “anchor” for Biogen’s broader nephrology plans, according to Keeney.

CEO Viehbacher echoed that enthusiasm for Empaveli as a broader kidney catalyst for Biogen, noting that the drug could help lay the foundation for the potential launch of Biogen’s late-stage felzartamab and help the drug get a “running start” to reach peak sales faster than if Biogen were starting from scratch commercially.

Felzartanab is currently in late-stage trials across three kidney disease indications—antibody-mediated rejection, immunoglobulin A nephropathy and primary membranous nephropathy—with Biogen expecting to deliver its first phase 3 readout in the first half of 2027. 

Biogen is striking its deal shortly after reporting a 2% sales increase to $9.9 billion in 2025, marking the first instance since 2019 that the company had reported an annual sales jump. 

At the time, Biogen said it did not expect that growth to continue into 2026, laying out a forecast predicting a mid-single-digit decline to a range of $9.3 billion to $9.5 billion for all of this year. 

In the wake of the announcement, Apellis shares more than doubled, while Biogen’s share price declined 4% by midmorning Tuesday.