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biib-20260701

0000875045false00008750452026-07-012026-07-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): July 1, 2026

Biogen Inc.

(Exact name of registrant as specified in its charter)

Delaware0-1931133-0112644

(State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

225 Binney Street, Cambridge, Massachusetts 02142

(Address of principal executive offices; Zip Code)

Registrant’s telephone number, including area code: (617) 679-2000

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered

Common Stock, $0.0005 par valueBIIBThe Nasdaq Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

☐ Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02     Results of Operations and Financial Condition

Biogen Inc. (Biogen) expects that its GAAP and non-GAAP results for the second quarter of 2026 will include acquired in-process research and development, upfront and milestone expense of approximately $164 million on a pre-tax basis. The estimated charge is expected to impact GAAP and non-GAAP net income per diluted share for the second quarter of 2026 by approximately $0.95 per share.

Additionally, Biogen anticipates its GAAP and non-GAAP results for the third quarter of 2026 to include acquired in-process research and development, upfront and milestone expense ranging from approximately $290 million to $320 million relating to potential milestones and transactions that have not yet closed. The estimated charge is anticipated to impact GAAP and non-GAAP net income per diluted share for the third quarter of 2026 ranging from approximately $1.75 to $1.95 per share.

Acquired in-process research and development, upfront and milestone expense includes costs incurred in connection with collaboration and license agreements such as upfront and milestone payments and, when applicable, premiums on equity securities and asset acquisitions of acquired in-process research and development. Biogen does not forecast such acquired in-process research and development, upfront and milestone expense due to the uncertainty of the future occurrence, magnitude and timing of these transactions in any given period.

Results for the quarter ended June 30, 2026, have not been finalized and are subject to our financial statement closing procedures. There can be no assurance that our final results will not differ from the preliminary unaudited estimates described herein.

Note Regarding Forward-Looking Statements

This Current Report on Form 8-K contains forward-looking statements relating to our financial and operating results and financial guidance, that are being made pursuant to the provisions of the Private Securities Litigation Reform Act of 1995 (the PSLRA) with the intention of obtaining the benefits of the “Safe Harbor” provisions of the PSLRA. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” "assume," “believe,” “contemplate,” “continue," "could," “estimate,” “expect,” “forecast,” “goal,” “guidance,” “hope,” “intend,” “may,” “objective,” "outlook," “plan,” “possible,” "potential," “predict,” “project,” “should,” “target,” “will,” “would” or the negative of these words or other words and terms of similar meaning.

Given their forward-looking nature, these statements involve substantial risks and uncertainties and may be based on inaccurate assumptions and could cause actual results to differ materially from those reflected in such statements. The information above includes, among others, forward-looking statements reflecting management’s current intentions and expectations for the future with respect to Biogen’s estim

EX-99.1

2 exhibit991-q12026pressrele.htm

EX-99.1

Document

Press Release

Cambridge, Mass. – April 29, 2026

Biogen reports strong first quarter 2026 results

First quarter 2026 total revenue of $2.5 billion, increased 2% year-over-year; GAAP diluted EPS of $2.15, increased 31% year-over-year; Non-GAAP diluted EPS of $3.57, increased 18% year-over-year

Growth products1 delivered 12% year-over-year growth demonstrating continued strong commercial execution

•LEQEMBI global in-market sales of $168 million, up 74% year-over-year, with U.S. in-market sales of $86 million, representing continued sequential growth

•SKYCLARYS global revenue of $151 million driven by demand growth, up 22% year-over-year

•ZURZUVAE revenue of $55 million, up 100% year-over-year, showed strong continued demand growth; sequential sales impacted by inventory dynamics

•VUMERITY global revenue of $179 million grew 29% year-over-year supported by inventory dynamics in the U.S.

•SPINRAZA global revenue of $374 million declined 12% year-over-year with ex-U.S. sales impacted by the timing of shipments

•QALSODY global revenue of $33 million, up 110% year-over-year, with continued demand growth

New data across key late-stage pipeline programs underscore the potential of the registrational pipeline

•Litifilimab second positive Phase 2 CLE dataset showed meaningful reduction of disease activity in people living with CLE at Week 16; if approved litifilimab could be the first targeted therapy for this disease

•Salanersen additional Phase 1b data showed unprecedented new motor milestones achieved in children with SMA who had suboptimal clinical status despite prior administration of gene therapy

•LEQEMBI real-world persistence data showed that approximately 78% of patients continued LEQEMBI at 18 months, with the majority continuing treatment into the maintenance phase

•SPINRAZA High Dose Regimen approved in the U.S. by the FDA following approvals in Japan and E.U.

Proposed acquisition of Apellis Pharmaceuticals bolsters growth outlook, adding commercialized medicines in immune-mediated retinal disease and nephrology, and deepening the foundation for Biogen's growing nephrology franchise. Transaction is subject to customary closing conditions

•Apellis transaction expected to be accretive in 2027

•Apellis is expected to materially increase Biogen’s Non-GAAP diluted EPS compounded annual growth rate through the end of the decade

Nephrology franchise further enhanced by agreement with TJ Biopharma to acquire exclusive rights to felzartamab in the Greater China region, potentially one of the largest patient populations globally for IgAN

Biogen updates full year 2026 guidance to reflect continued strong business outlook and investment for growth

•Full year 2026 Non-GAAP diluted EPS is now expected to be between $14.25 and $15.25, excluding any impact from the Apellis transaction. Updated guidance includes an approximately $1.00 impact from acquired IPR&D charges resulting from ongoing business development activities to support

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.

1

Biogen's growth strategy. This comprises approximately $0.20 recorded in the first quarter and approximately $0.80 expected in the second quarter

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

•With the Apellis transaction expected to close in the second quarter of 2026, Biogen plans to provide updated 2026 guidance inclusive of Apellis when it reports second quarter 2026 earnings

Biogen Inc. (Nasdaq: BIIB) today reported first quarter 2026 financial results. Commenting on the quarter, President and Chief Executive Officer Christopher A. Viehbacher said:

"We significantly advanced our transformation into the New Biogen through strong commercial and pipeline execution and the announcement of our intent to acquire Apellis. We believe the planned acquisition of Apellis will bolster our revenue and earnings growth, adding two differentiated commercial medicines and deepening the foundation for felzartamab, our key Phase 3 asset in kidney disease. This acquisition and the acquired rights to felzartamab in China come while we also expanded sales of our growth products, demonstrated continued resilience in our MS portfolio and reported important positive new data that reinforce our confidence in the late‑stage pipeline."

Financial Highlights

Q1 '26Q1 '25△

r (CC*)

Total Revenue (in millions)$2,478$2,4312%(2)%

GAAP diluted EPS$2.15$1.6431%N/A

Non-GAAP diluted EPS$3.57$3.0218%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.