Lecanemab

Biogen charted first-quarter sales growth thanks to the launches of Leqembi, Zurzuvae and Skyclarys. Burdened by competitive pressures for its stalwart multiple sclerosis franchise, Biogen has weathered years of sales declines. But in the first quarter, the company was able to see a glimpse of its hoped-for future with revenue growth thanks to three launches.Lately, Biogen's story can be summed up as a “a tale of two companies,” CEO Chris Viehbacher mused on a Thursday earnings call with analysts.There’s one company, a multiple sclerosis (MS)-centered drugmaker, with a portfolio that has been gradually declining, with its sales falling 11% during the first quarter. But now with 45% of Biogen's revenue coming from medicines outside of its MS franchise, “there’s a new Biogen emerging,” according to Viehbacher.The fresh start is hallmarked by Alzheimer’s disease med Leqembi, postpartum depression (PPD) treatment Zurzuvae and Friedreich’s ataxia therapy Skyclarys, all of which helped drive Biogen to a 6% revenue increase during the first quarter of 2025. Overall, the company generated $2.4 billion during the period. Eisai-partnered Leqembi is now into “serious product territory,” Viehbacher noted, growing a whopping 395% since last year’s first quarter—and 11% from the fourth quarter of last year—to $96 million in sales. The drug finally cinched a European approval in April after months of back-and-forth decisions by European officials, unlocking a key market with “an awful lot of eligible patients,” according to the CEO.It’s been a “challenging product to launch,” Viehbacher observed, but several recent advancements in administration—including an anticipated FDA decision for subcutaneous maintenance dosing—should help reduce the treatment burden.Currently, the Alzheimer’s antibody treatment market consists of Leqembi and Eli Lilly’s rival Kisunla (donanemab), which has faced many of the same launch barriers. Biogen accepts the competition, acknowledging that it will ultimately be “up to the physician and the patient” to determine which treatment to choose, Viehbacher explained.“I think the market ultimately gets split between us and donanemab,” the CEO said. “The most important thing for both Lilly and Biogen and Eisai is that we start to really expand this market.” As it stands, the companies are both only treating a “small fraction” of the patients who “desperately need treatment," the CEO said.Zurzuvae, meanwhile, has so far treated more than 10,000 women since its 2023 launch. Its sales were up 123% since last year’s first quarter to $28 million. Biogen managed to expand the number of physicians writing prescriptions by 20%, the company reported, in part by focusing on OB-GYNs as opposed to psychiatrists. The drug was the first oral medicine approved to specifically treat PPD. With Zurzuvae on the market, physicians are becoming “more proactive” about diagnosing the historically overlooked condition, Viehbacher commented.  Elsewhere, Biogen is still underway with a geographic expansion for Skyclarys, having scored recent approvals in the U.K. and Brazil. With $124 million in first-quarter sales, the drug was the biggest revenue contributor out of its three new launches. Friedreich’s ataxia is a genetic disease with European origin, leaving the Biogen team to get “very creative” in finding new U.S. patients through family trees and social media, according to the CEO.So far, around 2,400 patients are on the treatment globally; some are still on early access programs rather than commercial therapy. No concern for tariffs For many of Biogen's peers, the threat of looming pharmaceutical tariffs and changing trade policies could overshadow their future prospects. But Biogen's diversified revenue base means that some 55% of its product revenue last year came from sales outside of the U.S., which is “pretty unusual in our business,” Viehbacher said. And given that about 75% of last year’s U.S. product revenue is tied to drugs that have manufacturing operations in the U.S., Massachusetts-based Biogen is “more of a U.S.-based company” and is “quite proud of that,” the CEO noted. The drugmaker does not expect its financial outlook, which estimates a revenue decline by a mid-single-digit percentage in 2025 due to falling MS sales, to be impacted by currently announced tariffs, “even if the exemption for pharmaceuticals were to be removed,” the company said. Elsewhere in the policy vein, Biogen and Viehbacher have “not really seen” any delays in its interactions with the FDA or any “adverse effects” from key leaders who have left the agency.

Biogen said sales of its Eisai-partnered Alzheimer’s drug Leqembi crept close to the $100 million mark in the first three months of the year, after the product fared worse than expected during its US launch. Leqembi achieved $96 million in global sales in the first quarter, according to an earnings release issued Thursday. That figure is up more than 400% from $19 million during the same period in 2024. Around $52 million of Leqembi’s Q1 sales came from the US. The figures demonstrate “continued sequential growth” for the franchise, Biogen said in the release. Biogen splits net revenues from Leqembi down the middle with Japan’s Eisai under the terms of a deal inked in 2014. The product got off to a slow start on the US market after securing a full approval in mid-2023. The launch was hindered by several challenges, including the length of time it takes for a patient to begin treatment after their first visit to a doctor. But Biogen expects “a number of innovations” that could reduce the workload for doctors and accelerate uptake, CEO Chris Viehbacher told analysts on a same-day earnings call. Following the US approval of IV maintenance dosing, the company is anticipating a thumbs-up in August for subcutaneous maintenance dosing, which should enable at-home administration with an autoinjector. A green light for a subcutaneous initiation regimen is set to follow in the first half of 2026, which would “dramatically reduce the need for infusion bed capacity,” Viehbacher said. In November, Eisai slashed its Leqembi sales projections for full-year 2024 by a quarter, to around $280 million. And in March, it reduced expectations for Leqembi sales in 2027 to between $1.7 billion and $1.9 billion. Eisai had previously guided around $3.3 billion in 2027 sales. Elsewhere, Biogen appeared to suggest that it anticipates limited impact from potential pharma tariffs in the US. The company “operates a significant manufacturing presence in the US,” according to the release. “Roughly 75% of our 2024 US product revenues were generated by products which have manufacturing operations in the US,” Viehbacher said. Editor’s note: This article was updated to add comments from Biogen’s analyst call.