Biogen (BIIB) Earnings: Q3 2026 Results

The quarter ended September 30, 2026 and Biogen published the results on October 28, 2026. Revenue and diluted EPS are shown against Q3 2025, the same quarter a year earlier, which takes seasonal swings out of the comparison. Biogen reports EPS two ways: GAAP, under the accounting rules every US filer follows, and Non-GAAP, which leaves out items the company considers outside its operating results. The release reconciles the two, and when they diverge, the reconciliation says why.

• Biogen closed its acquisition of Apellis in May 2026, paying $41.00 a share in cash (about $5.3 billion) plus a contingent value right of up to $4.00 a share tied to SYFOVRE sales. Apellis added SYFOVRE and EMPAVELI, the new Specialized immunology line, so that line has no year-ago figure.
• Q3 2026 GAAP and Non-GAAP results both include $284 million of acquired IPR&D, upfront and milestone expense, mainly from the acquisition of RayThera Inc., against $2 million a year earlier.

Source: Biogen Q3 2026 results, October 28, 2026. Also in the Form 10-Q for the quarter ended September 30, 2026. Figures as reported; checked against the release on November 10, 2026.

How Biogen splits revenue in its own release, under its own labels, for Q3 2026 against Q3 2025. Indented lines are parts of the line above them.

• Biogen's Multiple sclerosis (MS) product revenue revenue was $919 million in Q3 2026, down 13% from $1.1 billion in Q3 2025, 33% of total revenue.
• Biogen's Rare disease revenue revenue was $676 million in Q3 2026, up 27% from $533 million in Q3 2025, 24% of total revenue.
• Biogen's Specialized immunology revenue revenue was $243 million in Q3 2026, 9% of total revenue.
• Biogen's Biosimilars revenue revenue was $166 million in Q3 2026, down 16% from $197 million in Q3 2025, 6% of total revenue.
• Biogen's Other product revenue revenue was $84.4 million in Q3 2026, up 53% from $55.3 million in Q3 2025, 3% of total revenue.
• Biogen's Revenue from anti-CD20 therapeutic programs revenue was $497 million in Q3 2026, up 1% from $494 million in Q3 2025, 18% of total revenue.
• Biogen's Alzheimer's collaboration revenue revenue was $68.4 million in Q3 2026, up 60% from $42.7 million in Q3 2025, 2% of total revenue.
• Biogen's Contract manufacturing, royalty and other revenue revenue was $150 million in Q3 2026, down 1% from $151 million in Q3 2025, 5% of total revenue.

Segment lines are the figures writers cite most often, because they show where the growth in a quarter came from. Companies redraw their segments from time to time and restate the prior year to match, so a year-ago figure here can differ from the one printed a year ago. When that has happened, the note above says so.

From the earnings release

In its Q3 2026 release, Biogen said:

“Biogen raises the lower end of the reported range to $12.20 to $13.00 from $12.00 to $13.00 reflecting ongoing business strength and Apellis dilution favorability”

“Full year total revenue is expected to increase by a mid-single digit percentage for 2026 as compared to 2025 driven by continued growth from our Growth Portfolio.”

“Biogen expects combined Non-GAAP R&D expense and Non-GAAP SG&A expense to be approximately $4.95 billion for the full year 2026.”

Source: Biogen Q3 2026 release, Oct 28, 2026.

This is the company's own guidance as of Oct 28, 2026, quoted as given. Walnut does not make forecasts of its own. Analyst estimates for the coming quarters are on the BIIB forecast page.

Revenue and diluted EPS for the last 5 quarters. Each date links to that quarter's release.

GAAP total revenue and diluted EPS, each as first reported in that quarter's release.

We do not hold a confirmed date for Biogen's next report. Companies post the date on their investor relations site a few weeks ahead, usually with the time of the conference call.

Each quarter keeps its own page with the figures as reported, so a link to one stays pointed at the same numbers after the next report.

• Q3 2026 (this page), reported Oct 28, 2026

Biogen's total revenue rose 11% to $2,804.1 million in Q3 2026, or 10% at constant currency. Product revenue was $2,088.7 million. The rest came from anti-CD20 therapeutic programs run by Genentech ($497.3 million, mostly a $369.9 million royalty on OCREVUS), Biogen's 50% share of the LEQEMBI collaboration with Eisai ($68.4 million), and contract manufacturing, royalty and other revenue ($149.7 million). (Biogen Q3 2026 release, Oct 28, 2026)

Biogen's revenue is shifting from multiple sclerosis to what it calls the Growth Portfolio. MS product revenue fell 13% to $919.3 million as TECFIDERA dropped to $82.0 million from $168.2 million and VUMERITY fell 11%, which Biogen attributed to U.S. formulary dynamics. TYSABRI, at $437.1 million, was the largest MS product. The Growth Portfolio brought in $1.26 billion, up 49%, and was 63% of Core Pharmaceutical revenue. (Biogen Q3 2026 release, Oct 28, 2026)

Rare disease revenue rose 27% to $676.3 million. SPINRAZA grew 23% to $460.6 million, which Biogen tied to faster conversion to its high-dose regimen, and SKYCLARYS grew 34% to $178.2 million on U.S. and international demand and favorable U.S. inventory dynamics. The new Specialized immunology line from the Apellis acquisition added $242.8 million: SYFOVRE $191.3 million and EMPAVELI $51.5 million, all in the U.S. (Biogen Q3 2026 release, Oct 28, 2026)

U.S. product revenue was $1,265.0 million and rest of world $823.7 million. Biosimilars, sold only outside the U.S. in the quarter, fell 16% to $165.9 million. ZURZUVAE, sold with Supernus in the U.S., grew 53% to $84.4 million. Under its Genentech agreements, Biogen earns a tiered royalty of 13.5% rising to 24.0% on U.S. OCREVUS net sales, which halves when the first FDA approved OCREVUS biosimilar enters. (Biogen Q3 2026 release, Oct 28, 2026; Biogen Form 10-K, 2025, Feb 6, 2026)

Biogen reported a GAAP diluted loss of $0.14 a share in Q3 2026, against EPS of $3.17 a year earlier, on a net loss of $20.6 million. Non-GAAP diluted EPS was $2.62, against $4.81. Both measures absorb $284 million of acquired IPR&D, upfront and milestone expense, mainly for the RayThera acquisition. Because that charge is not tax deductible, the GAAP effective tax rate was (128.5)%, against a Non-GAAP rate of 20.0%. (Biogen Q3 2026 release, Oct 28, 2026)

The gap between GAAP and Non-GAAP comes mostly from acquisition accounting and restructuring. Non-GAAP results exclude $194.8 million of amortization of the inventory fair value step-up from the Reata and Apellis acquisitions, $160.2 million of amortization of acquired intangible assets, $66.5 million of restructuring charges and a $33.3 million loss on equity security investments. (Biogen Q3 2026 release, Oct 28, 2026)

Operating costs rose with Apellis. GAAP R&D expense increased to $574.0 million from $436.1 million on clinical trial spending for felzartamab, salanersen and litifilimab, and SG&A rose to $752.0 million from $594.8 million. Weighted average diluted shares were about 148 million for GAAP and 149 million for Non-GAAP EPS. Biogen had about $7.7 billion of debt and $1.3 billion of cash at quarter end. (Biogen Q3 2026 release, Oct 28, 2026)

Diluted EPS divides net income by the weighted average number of shares outstanding in the quarter, plus the shares that options and other equity awards could add. Buybacks shrink that count and lift EPS for the same profit; share issuance and stock awards enlarge it.

Biogen guides on Non-GAAP diluted EPS and revenue growth. In October 2026 it raised the low end of full-year 2026 Non-GAAP diluted EPS guidance to $12.20 to $13.00, from $12.00 to $13.00. That figure includes about ($3.20) of acquired IPR&D, upfront and milestone charges and about ($0.55) of expected dilution from Apellis; the underlying range is $15.95 to $16.75. Biogen expects total revenue to grow by a mid-single digit percentage in 2026. (Biogen Q3 2026 release, Oct 28, 2026)

Biogen expects combined Non-GAAP R&D and SG&A expense of about $4.95 billion for 2026 and does not give GAAP EPS guidance. It expects topline data from the TOPAZ-1 and TOPAZ-2 Phase 3 studies of litifilimab in SLE in the first half of December 2026. (Biogen Q3 2026 release, Oct 28, 2026)

A consensus figure is the average of the models published by the analysts who cover Biogen, collected by a data provider and revised up to the day of the report. A quarter that lands above it says how expectations were set as much as how the business did, and the share price on the day also reflects the guidance and the lines no consensus covers.

The consensus figures on this page are Yahoo Finance's, as pulled on the date shown. Each comes with the number of analysts behind it; the smaller that number, the more one revised estimate can move the average.

The figures below are the ones Biogen's own release and filings put weight on for Q3 2026, with the latest reported value for each.

What the quarter means for a holding is a separate question from what it reported. The case for and against owning BIIB is on is BIIB a buy or a sell?, what analysts expect next is on the BIIB forecast, and what the company does is on the Biogen (BIIB) stock page.

Every number on this page can be traced to a document Biogen published. Checking one takes a couple of minutes, and it is worth doing before you quote a figure anywhere.

• The results release is the document linked in the source line above. Companies publish it on their investor relations site at the moment results go out, and it carries the headline tables: revenue, operating income, net income and EPS for the quarter and the year-ago quarter.
• The same release is filed with the SEC as Exhibit 99.1 to a Form 8-K under Item 2.02, usually on the day of the report. The SEC copy does not change after the fact, which makes it the safer thing to link when you cite a number.
• The quarterly report (Form 10-Q) follows within a few weeks and carries the full financial statements, the segment note and management's discussion of what changed. The fourth quarter is covered by the annual report (Form 10-K) instead.
• Restated comparisons are flagged in the notes on this page. When a company redraws its segments or changes how it adjusts EPS, it restates the year-ago column, so the year-ago figure in a new release can differ from the one printed a year ago. This page always uses the comparison in the newer release, because that is the like-for-like one.

A walk-through of every line in a release, with what each one tells you, is in how to read an earnings report.