While the continued erosion of Biogen’s multiple sclerosis franchise and weaker-than-expected 2025 guidance doesn’t seem to be sitting well with investors, company leadership remains confident that a crop of new drugs can pick up the slack in the months and years to come.
“As you all know, we have been faced with increased competition for our multiple sclerosis franchise, and really all of our priorities are thinking about ‘how do we build a new Biogen, how do we build a new phase of growth,’” the company’s CEO, Chris Viehbacher, said on a call with analysts Wednesday.
To chart that change, Biogen is focusing on building up four recent drug launches, reprioritizing its pipeline and cutting operating expenses, Viehbacher said. On the last point, Biogen has been undergoing a restructuring initiative under Viehbacher to help save around $1 billion by the end of this year.
Still, investor sentiment around Biogen’s earnings release was lukewarm, with the company’s share price trading down more than 5% on Wednesday.
In the fourth quarter, sales for Biogen’s multiple sclerosis (MS) franchise—which includes drugs like Tysabri and Tecfidera—declined 9% at constant currencies to a little more than $1 billion. For all of 2024, Biogen’s multiple sclerosis sales came in at $4.4 billion, a 7% drop over the sum the business brought home in 2023.
Much of that decline was driven by generic competition to Tecfidera around the world, as well as Tysabri’s limited exposure to biosimilars in Europe, Michael McDonnel, Biogen’s outgoing finance chief, said on the company’s call.
“Although a biosimilar has not yet launched in the U.S., we continue to see competition increasing in the high efficacy class,” McDonnell said of Tysabri’s performance at home.
Summarizing the current situation Biogen finds itself in, Viehbacher postulated that there’s about $4.5 billion left to gain in MS revenue, and about $3 billion in remaining profit for the business.
“So that’s going to be the headwind over the next five to 10 years,” he said.
The silver lining for Biogen, however, is that sales from four recent launches—Skyclarys, Leqembi, Zurzuvae and Qalsody— “more than offset the decline in our multiple sclerosis product revenue,” according to Viehbacher.
Skylcarys, approved in the rare neuromuscular disorder Friedreich’s ataxia in early 2023, ginned up sales of $102 million in the fourth quarter, with Biogen noting in its earnings release that it has nearly doubled the number of patients on the therapy globally compared to the end of 2023.
Overall, Biogen estimates there are about 4,800 Friedreich’s ataxia patients in the U.S., according to Viehbacher. Locating those potential Skyclarys users is tricky, though, given that the company is dealing with “quite a large prescriber base for a very narrow patient population," the CEO acknowledged.
Elsewhere, Biogen’s launch of Zurzuvae in postpartum depression last year “certainly exceeded our expectations,” said Viehbacher, who pointed out that roughly 80% of prescriptions for the drug are being written by obstetrician-gynecologists (OB-GYNs), rather than the high-prescribing psychiatrists Biogen had initially tried to target.
The company is hopeful it can expand Zurzuvae’s reach in 2025 thanks to regulatory filings currently under review in Europe, the United Kingdom and Canada, the CEO added.
As for Qalsody, which was approved by the FDA to treat amyotrophic lateral sclerosis (ALS) in April 2023, the oligonucleotide drug is “not necessarily a big revenue generator,” though it still has merit as a “breakthrough treatment in ALS,” Viehbacher said on Biogen’s earnings call.
“This is the first time we’ve been able to demonstrate that neurofilament can really help predict drugs early in development as to whether or not they are likely to work, and that allows just the whole research and development in ALS to be accelerated,” Viehbacher explained.
As for Biogen’s Eisai-partnered Alzheimer’s disease drug Leqembi—which has been expanding more sluggishly in the U.S. than many initially expected—Viehbacher described the antibody’s growth trajectory in 2024 as “good, steady, quarter-on-quarter progress.”
For the last three months of 2024, Leqembi generated global sales of $87 million, growing about 30% quarter over quarter.
Viehbacher was quick to acknowledge that Leqembi’s performance overseas has been significant in the drug’s overall rollout thus far.
“Clearly, the ex-U.S. launch is contributing more than we have seen in prior launches in other areas,” the CEO said, chalking up the trend to a number of factors, including Eisai’s strength in its home territory of Asia, as well as the prevalence of single-payer systems outside the U.S., which remove many of the obstacles that can impede treatment uptake stateside.
Echoing statements made by Eisai management last week, Viehbacher highlighted several potential growth catalysts for Leqembi moving forward, such as the FDA’s recent approval of a less burdensome, four-week maintenance dosing schedule for the drug, as well as an expected increase in quality blood-based diagnostics that could make identification of eligible patients easier.
Biogen and Eisai also expect the FDA to make a decision on the approval of a subcutaneous autoinjector version of Leqembi late this summer, which could present patients and caregivers with the option to administer the antibody at home.
Overall, Biogen’s fourth-quarter revenues clocked in at $2.46 billion, coming in above Wall Street’s estimate of $2.41 million. Full-year revenues declined 2% over 2023 to $9.7 billion, which fell in line with Biogen’s established 2024 guidance.
Looking at the year ahead, Biogen expects 2025 revenue to fall by a mid-single-digit percentage point versus 2024. That’s a greater fall than consensus expectations of a 2.8% decline this year, analysts at William Blair wrote in a note to clients Wednesday.