In addition to delivering two approved medicines to Biogen’s portfolio, the acquisition of Apellis Pharmaceuticals will support the future launch of the pharma’s own kidney disease asset, currently in multiple Phase 3 trials.
Biogen isn’t just buying Apellis Pharmaceuticals and two approved medicines in kidney and eye disease for $5.6 billion; it’s also gaining the know-how of a biotech that has already served the nephrology space.
Analysts heralded the deal as an effort in diversification and stocking up on a team that can lay a path for the successful launch of Biogen’s felzartamab, a CD38 targeting antibody for kidney disease acquired in the $1.8 billion takeover of Human Immunology Biosciences (HI-Bio) in 2024. But others worried about the premium paid and competitive dynamics in Apellis’ existing markets.
Felzartamab is currently in multiple Phase 3 trials across three kidney diseases with readouts beginning in 2027. The company hopes to eventually seek approval of felzartamab for immunoglobulin A nephropathy (IgAN), primary membranous nephropathy (PMN) and antibody-mediated rejection (AMR).
Apellis’ Empaveli is approved for three other kidney diseases, providing Biogen with a revenue-generating asset and access to prescribers in the kidney space ahead of the investigational product’s launch.
“We just think that if the clinical trials work out for felzartamab as we hope, that we will have a running start into the launch, and we could actually potentially achieve peak sales faster than we would if we were just doing on this on our own,” CEO Chris Viehbacher said on a Tuesday morning conference call.
Stifel agreed, noting that the salesforce and commercial infrastructure from Apellis “should help them hit the ground running” with felzartamab.
Viehbacher said that Apellis fits perfectly into Biogen’s strategy. Executives at the company—which has conducted just three buyouts since 2020—have been peppered with questions about M&A over the past few quarters, given that the pipeline is still in its early stages. The CEO said that they didn’t want to take on a lot of Phase 3 risk; rather, they wanted to differentiate beyond neuroscience and the price had to be right without stretching the balance sheet. That final piece has been tough to achieve in a cutthroat pharma deal environment.
RBC Capital Markets agreed that Apellis offers no real clinical risk with its commercial assets, but both programs come with baggage and established rivals. “[W]e can see some aspects that may mute enthusiasm,” the firm wrote.
Viehbacher said that Biogen began looking at Apellis a year ago while conducting thorough market research in the kidney space. Novartis has an early-stage asset that will rival Biogen’s burgeoning kidney franchise, Viehbacher noted, but he brushed off competitive concerns.
“We feel comfortable that we’re going to be able to work with the Apellis teams to really pull the teams together and do even more with these two products than either company could do on their end.”
While the diseases are different between felzartamab and Empaveli, there is significant overlap in terms of expertise and the prescriber base, explained Alisha Alaimo, president and head of North America at Biogen.
“Hiring in nephrology is actually not so easy. It’s a competitive space,” Alaimo explained. Instead of seeking these individuals out for the future launch of felzartamab, Biogen felt that Apellis could provide the team they need. Viehbacher said that the commercial team at Apellis is about 350 strong.
“We are looking to try to retain as much talent as possible in that organization,” the CEO said.
Power Through 2028
Empaveli is not the only drug that Biogen will get. Syfovre is approved for the immune-mediated eye disease geographic atrophy secondary to age related macular degeneration, a competitive area with rivals including Regeneron and Annexon.
Empaveli and Syfovre combined for $689 million in revenue for 2025, according to Biogen’s Tuesday release. The drugs are expected to grow through at least 2028, a key date for Biogen when its existing pipeline is expected to start providing revenue.
“With both Empaveli/Syfovre expected to grow revenues in the coming years, successful acquisition of Apellis could start to meaningfully change how investors think about the revenue growth story for the company,” BMO Capital Markets analysts wrote on Tuesday morning.
Biogen has been managing the decline of its multiple sclerosis franchise for several years, with Viehbacher—who joined in 2022—overseeing a major diversification effort.
Biogen will pay $41 per share for Apellis, plus a contingent value right to stockholders providing two payments of $2 per share held payable upon certain global net sales benchmarks for Syfovre. Because there are no indication overlaps, BMO does not see any potential for regulatory problems from the Federal Trade Commission even though both companies hold kidney disease assets.
Stifel, while agreeing that Apellis appears to be a strategic fit, questioned the value. Apellis is expected to achieve revenue of about $1.5 billion in 2030.
“APLS revenue consensus for 2030 is $1.5B—if achieved BIIB would’ve paid ~3.5x this number (not crazy at all)—but that arguably may be ambitious as it signals a durable uptick in the growth rate for Syfovre, and >$600MM in sales for Empaveli,” Stifel wrote.
Viehbacher noted that the premium “looks high” as compared to Apellis’ current stock price, but assured investors and analysts that the deal was backed by strong due diligence and forecasted revenues.
“We’ve looked at a whole range of companies,” Viehbacher said. “You can pretty much assume that anything under $5 billion of market cap we have looked at, and we believe that this was the best opportunity that really fits strategically with Biogen and where our pipeline is taking us.”
