Biogen reports strong fourth quarter and full year 2025 results and provides full year 2026 financial guidance

Fourth quarter 2025 total revenue $2.3 billion; GAAP diluted EPS $(0.33); Non-GAAP diluted EPS $1.99

Full year 2025 total revenue $9.9 billion; GAAP diluted EPS $8.79; Non-GAAP diluted EPS $15.28, exceeding the upper end of our 2025 full year guidance range of $14.50 to $15.00

Growth products1 up 6% year-over-year in the fourth quarter demonstrating continued strong commercial execution

•LEQEMBI fourth quarter global in-market sales of approximately $134 million, up 54% year-over-year, with U.S. in-market sales of approximately $78 million, representing continued growth

•SKYCLARYS grew global patients on therapy by approximately 30% in 2025; fourth quarter U.S. revenue of approximately $89 million driven by demand growth, with ex-U.S. revenue of approximately $44 million reflecting continued demand growth, also impacted by a one-time reimbursement true-up

•ZURZUVAE fourth quarter revenue of approximately $66 million showed strong continued demand growth

•VUMERITY grew 3% year-over-year in the fourth quarter

•SPINRAZA fourth quarter revenue declined 15% year-over-year, impacted by timing of shipments outside the U.S., with full year revenue down 2% year-over-year

•Full year 2025 revenue from growth products increased 19% year-over-year and offset the year-over-year revenue decline from multiple sclerosis products, excluding VUMERITY

Continued to deliver progress across key late-stage pipeline programs

•LEQEMBI IQLIK subcutaneous treatment initiation granted FDA Priority Review with a PDUFA date of May 24, 2026; regulatory filings under review in Japan and China

•FDA Breakthrough Therapy Designation granted for litifilimab in cutaneous lupus (CLE), a disease with no targeted treatment options; both litifilimab Phase 3 systemic lupus (SLE) studies expected to read out in Q4 2026

•High dose regimen of SPINRAZA approved in Japan and E.U.; U.S. FDA PDUFA of April 3, 2026

•BTK degrader (BIIB145) targeting autoimmune diseases Phase 1 study initiated in healthy volunteers

Full year 2026 financial guidance reflects continued business momentum and financial discipline

•Full year 2026 Non-GAAP diluted EPS expected to be between $15.25 and $16.25

•Expect full year 2026 total revenue to decline by a mid-single digit percentage versus full year 2025

Biogen Inc. (Nasdaq: BIIB) today reported fourth quarter and full year 2025 financial results. Commenting on the results, President and Chief Executive Officer Christopher A. Viehbacher said:

"Our 2025 performance reflected continued focus on strong execution and financial discipline, driven by our revenue of nearly $1 billion from LEQEMBI, SKYCLARYS, ZURZUVAE, and QALSODY, progression of our pipeline, and resilience of our MS franchise. Our pipeline momentum continues with a strong start in 2026, with the FDA recently granting Priority Review for LEQEMBI IQLIK initiation and Breakthrough Therapy Designation for litifilimab in CLE. These milestones highlight both the innovative and differentiated value of our medicines and the strength of our late-stage pipeline. Going into 2026, we are looking forward to data

1 Growth products include SKYCLARYS, QALSODY, ZURZUVAE, VUMERITY and SPINRAZA, plus Biogen's 50% share of net revenue and cost of sales, including royalties, from the LEQEMBI Collaboration.

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from two Phase 3 studies in lupus for litifilimab, with 10 additional potentially registrational studies across our pipeline expected to read out sequentially over the next four years. This multi-year registrational data flow has the potential to drive meaningful innovation for patients and long-term value for shareholders."

Financial Highlights

						Q4 '25						Q4 '24						fav/(unfav)						fav/(unfav) at CC*						FY '25						FY '24						fav/(unfav)						fav/(unfav) at CC*
Total Revenue (in millions)						$2,279						$2,455						(7)%						(7)%						$9,891						$9,676						2%						2%
GAAP diluted EPS						$(0.33)						$1.83						(118)%						N/A						$8.79						$11.18						(21)%						N/A
Non-GAAP diluted EPS						$1.99						$3.44						(42)%						N/A						$15.28						$16.47						(7)%						N/A

Note: Percent changes represented as favorable/(unfavorable) versus the prior year period. N/A = not applicable.

* Percentage changes in revenue growth at constant currency (CC) are presented excluding the impact of changes in foreign currency exchange rates and hedging gains or losses. Foreign currency revenue values are converted into U.S. dollars using the exchange rates from the end of the previous calendar year.

A reconciliation of GAAP to Non-GAAP financial measures can be found in Table 4 at the end of this news release.

Revenue Summary

(In millions, except percentages)						Q4 '25						Q4 '24						fav/(unfav)						fav/(unfav) at CC*						FY '25						FY '24						fav/(unfav)						fav/(unfav) at CC*
Multiple Sclerosis (MS) product revenue(1)						$917						$1,070						(14)%						(15)%						$4,039						$4,350						(7)%						(7)%
Rare disease revenue(2)						$515						$535						(4)%						(4)%						$2,154						$1,988						8%						9%
Biosimilars revenue						$170						$202						(16)%						(15)%						$729						$793						(8)%						(7)%
Other product revenue(3)						$66						$26						157%						158%						$197						$83						139%						140%
Total product revenue						$1,667						$1,833						(9)%						(9)%						$7,119						$7,214						(1)%						(1)%
Revenue from anti-CD20 therapeutic programs						$521						$465						12%						12%						$1,861						$1,750						6%						6%
Alzheimer's collaboration revenue(4)						$47						$27						77%						76%						$178						$60						197%						197%
Contract manufacturing, royalty and other revenue						$44						$130						(66)%						(66)%						$733						$653						12%						12%
Total revenue						$2,279						$2,455						(7)%						(7)%						$9,891						$9,676						2%						2%

Note: Percent changes represented as favorable/(unfavorable) versus the prior year period. Numbers may not foot or recalculate due to rounding. NMF = no meaningful figure.

(1) MS includes TECFIDERA®, VUMERITY®, AVONEX®, PLEGRIDY®, TYSABRI® and FAMPYRA™. Effective January 1, 2025, our collaboration and license agreement for FAMPYRA global commercialization rights was terminated.

(2) Rare disease includes SPINRAZA®, SKYCLARYS® and QALSODY®.

(3) Other includes ZURZUVAE®, ADUHELM® and FUMADERM™.

(4) Includes Biogen's 50% share of net revenue and cost of sales, including royalties, from the LEQEMBI® Collaboration.

Expense Summary

(In millions, except percentages)						Q4 '25						Q4 '24						fav/(unfav)						FY '25						FY '24						fav/(unfav)
GAAP cost of sales*						$496						$583						15%						$2,404						$2,310						(4)%
% of Total Revenue						22%						24%												24%						24%
Non-GAAP cost of sales*						$445						$540						18%						$2,089						$2,137						2%
% of Total Revenue						20%						22%												21%						22%
GAAP R&D expense						$509						$513						1%						$1,779						$1,980						10%
Non-GAAP R&D expense						$478						$509						6%						$1,731						$1,868						7%
GAAP SG&A expense						$683						$680						-%						$2,434						$2,404						(1)%
Non-GAAP SG&A expense						$678						$673						(1)%						$2,421						$2,340						(3)%
GAAP and Non-GAAP acquired IPR&D, upfront and milestone expense						$222						$19						NMF						$472						$62						NMF

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Note: Percent changes represented as favorable/(unfavorable) versus the prior year period.

IPR&D = in-process R&D. NMF = no meaningful figure.

*Excluding amortization and impairment of acquired intangible assets.

•The decrease in fourth quarter 2025 GAAP and Non-GAAP cost of sales as a percentage of total revenue was driven primarily by favorable product mix including lower contract manufacturing revenue.

•The increase in full year 2025 GAAP cost of sales as a percentage of total revenue was driven primarily by a pre-tax charge related to a judgment on Genentech's claim for past royalties and interest on sales of TYSABRI. The decrease in full year 2025 Non-GAAP cost of sales as a percentage of total revenue was driven primarily by favorable product mix.

•The decrease in fourth quarter and full year 2025 GAAP and Non-GAAP R&D expense was driven primarily by the favorable impact from the Company's Fit for Growth initiative and R&D funding received, partially offset by increased investment in late-stage programs including felzartamab and litifilimab.

•The increase in fourth quarter and full year 2025 GAAP and Non-GAAP SG&A expense was driven primarily by sales and marketing spend to support product launches, partially offset by savings from the Company's Fit for Growth initiative.

•Fourth quarter 2025 GAAP and Non-GAAP acquired IPR&D, upfront and milestone expense was approximately $222 million.

Other Financial Highlights

•Fourth quarter 2025 GAAP and Non-GAAP collaboration profit sharing was a net expense of approximately $70 million. This includes approximately $47 million related to Biogen's collaboration with Samsung Bioepis, and approximately $22 million related to Biogen's collaboration with Supernus Pharmaceuticals, Inc. related to the commercialization of ZURZUVAE in the U.S.

•Full year 2025 GAAP and Non-GAAP collaboration profit sharing was a net expense of approximately $290 million. This includes approximately $219 million related to Biogen's collaboration with Samsung Bioepis, and approximately $71 million related to Biogen's collaboration with Supernus Pharmaceuticals, Inc. related to the commercialization of ZURZUVAE in the U.S.

•Fourth quarter 2025 GAAP other expense was approximately $154 million and includes approximately $131 million related to litigation matters. Fourth quarter 2025 Non-GAAP other expense was approximately $46 million, primarily driven by net interest expense.

•Full year 2025 GAAP other expense was approximately $306 million and includes the aforementioned approximately $131 million related to litigation matters. Full year 2025 Non-GAAP other expense was approximately $179 million, primarily driven by net interest expense.

•Fourth quarter 2025 GAAP and Non-GAAP effective tax rates were 12.8% and 10.1%, respectively. Fourth quarter 2024 GAAP and Non-GAAP effective tax rates were 8.5% and 12.2%, respectively.

•Full year 2025 GAAP and Non-GAAP effective tax rates were 16.9% and 15.5%, respectively. Full year 2024 GAAP and Non-GAAP effective tax rates were 14.4% and 14.6%, respectively.

Financial Position

•Fourth quarter 2025 net cash flow from operations was approximately $512 million. Capital expenditures were approximately $44 million, and free cash flow, defined as net cash flow from operations less capital expenditures, was approximately $468 million.

•Full year 2025 net cash flow from operations was approximately $2.2 billion. Capital expenditures were approximately $154 million, and free cash flow, defined as net cash flow from operations less capital expenditures, was approximately $2.1 billion.

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•As of December 31, 2025, Biogen had cash and cash equivalents totaling approximately $4.2 billion with approximately $6.3 billion in total debt, resulting in net debt of approximately $2.0 billion.

•For the fourth quarter of 2025 the Company's weighted average shares were 147 million and 148 million, used to calculate the Company's GAAP and Non-GAAP diluted EPS, respectively. All unvested equity-based awards are antidilutive for GAAP due to reporting a net loss for the fourth quarter of 2025. For full year 2025 the Company's weighted average diluted shares were 147 million.

Full Year 2026 Financial Guidance

For the full year 2026, Biogen expects a Non-GAAP diluted EPS guidance range as follows:

						Full Year 2026 Guidance
Non-GAAP diluted EPS						$15.25 to $16.25

Total revenue is expected to decline by a mid-single digit percentage for 2026 as compared to 2025 as further declines in multiple sclerosis product revenue, excluding VUMERITY, are expected to be partially offset by increases in revenue from growth products.

For full year 2026 as compared to full year 2025, Biogen expects the gross margin percentage, and combined Non-GAAP R&D expense and Non-GAAP SG&A expense to be roughly consistent year-over-year. Biogen expects full year 2026 Non-GAAP effective tax rate to be between approximately 17% and 18%.

This guidance also assumes that foreign exchange rates as of January 30, 2026, will remain in effect for the remainder of the year, net of hedging activities.

Unless expressly stated above, this financial guidance does not include any acquired IPR&D, impact from potential acquisitions or business development transactions or pending and future litigation or any impact of potential healthcare reform, as all are hard to predict. Other important financial considerations will be provided on the conference call and webcast.

Biogen may incur charges, realize gains or losses, or experience other events or circumstances in 2026 that could cause any of these assumptions and expectations to change and/or actual results to vary from this financial guidance.

Biogen does not provide guidance for GAAP reported financial measures (other than revenue) or a reconciliation of forward-looking Non-GAAP financial measures to the most directly comparable GAAP reported financial measures because the Company is unable without unreasonable effort to predict with reasonable certainty the financial impact of items such as the transaction, integration, and certain other costs related to acquisitions or large business development transactions; unusual gains and losses; potential future asset impairments; gains and losses from equity security investments; and the ultimate outcome of pending or future litigation. These items are uncertain, depend on various factors, and could have a material impact on GAAP reported results for the guidance period. For the same reasons, the Company is unable to address the significance of the unavailable information, which could be material to future results.

Conference Call and Webcast

The Company's earnings conference call for the fourth quarter will be broadcast via the internet at 8:30 a.m. ET on February 6, 2026 and will be accessible through the Investors section of Biogen's website, www.biogen.com. Supplemental information in the form of a slide presentation is also accessible at the same location on the internet and will be subsequently available on the website for at least 90 days.

About Biogen

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Founded in 1978, Biogen is a leading biotechnology company that pioneers innovative science to deliver new medicines to transform patient's lives and to create value for shareholders and our communities.

We apply deep understanding of human biology and leverage different modalities to advance first-in-class treatments or therapies that deliver superior outcomes. Our approach is to take bold risks, balanced with return on investment to deliver long-term growth.

We routinely post information that may be important to investors on our website at www.biogen.com. Follow us on social media - Facebook, LinkedIn, X, YouTube.

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