01—Abstract
Summary
Summary of the 10-K filed February 6, 2026. Cited figures are marked; the original filing is the authoritative source.
Biogen's FY2025 10-K shows a company in transition: total revenue grew 2.2% to $9.89 billiona, but product revenue fell 1.3% to $7.12 billion as MS franchise erosion (down 7.1%, driven by TECFIDERA generics and TYSABRI biosimilar competition) offset growth in rare disease (up 8.4%) and new launches.
Diluted EPS fell 21.4% to $8.79b, reflecting higher acquired IPR&D and upfront/milestone expense ($471.8 million, up from $61.5 million), a $104.9 million royalty cost charge tied to a litigation matter, $139.5 million of other litigation-related expense (including the Convergence settlement in principle), and a $52.9 million ROU asset impairment on the Reata Plano lease. Cash generation weakened: operating cash flow fell to $2.2 billion from $2.9 billion, partly due to roughly $864 million of tax payments. Cash, equivalents and marketable securities rose to $4.2 billion, helped by $200 million of Royalty Pharma litigation-related funding for litifilimab and $1.75 billion of new senior notes that refinanced the 2025 maturity.
Total borrowings were essentially flat at $6.3 billionc, and the $2.1 billion remaining buyback authorization went unused in 2025. Looking ahead, management expects continued MS revenue decline, growth in rare disease (SKYCLARYS, QALSODY), flat SPINRAZA, and a slight increase in core R&D in 2026, with relatively flat SG&A.
Key catalysts include the April 3, 2026 PDUFA for high-dose SPINRAZA, the May 24, 2026 PDUFA for LEQEMBI IQLIK starting dose, late-stage readouts for felzartamab, litifilimab and zorevunersen, and the 2026 Phase 3 start for salanersen. Risks include pricing pressure from the IRA and MFN policy, ongoing litigation (including a $124.3 milliond Genentech judgment under appeal and a German tax assessment of about $246.5 million), and dependence on the Eisai LEQEMBI collaboration.
02—Key points
Key Highlights
- Total revenue rose 2.2% to $9.89 billion, but product revenue fell 1.3% to $7.12 billion as MS products declined 7.1%.
- Rare disease revenue grew 8.4% to $2.15 billion, led by SKYCLARYS ($520.5 million, up 36.1%) and QALSODY ($86.9 million, up 168.2%); ZURZUVAE reached $195.1 million.
- Diluted EPS fell 21.4% to $8.79, reflecting $471.8 million of acquired IPR&D and milestone expense, $139.5 million of litigation-related expense, a $104.9 million royalty cost-of-sales charge, and a $52.9 million ROU impairment.
- Operating cash flow declined to $2.2 billion from $2.9 billion, pressured by roughly $864 million of tax payments; cash and marketable securities rose to $4.2 billion.
- Business development was active: Stoke ($165M upfront), Vanqua ($70M), Dayra ($50M), City Therapeutics ($16M plus a $30M convertible note), and the Alcyone acquisition (about $85M consideration) all closed in 2025.
- Pipeline catalysts in 2026 include the SPINRAZA high-dose PDUFA on April 3, the LEQEMBI IQLIK starting-dose PDUFA on May 24, Phase 3 readouts for felzartamab, litifilimab and zorevunersen, and the planned Phase 3 start for salanersen.
- Total borrowings were stable at $6.3 billion after issuing $1.75 billion of 2031-2055 senior notes to redeem the $1.75 billion 4.050% notes due 2025; about $2.1 billion remains under the buyback authorization, with no repurchases in 2025.
03—One dollar
04—Financials
Financial Highlights
Figures from 10-KFY2025filed February 6, 2026Financial Statements
FY2025 against FY2024
| Line item | FY2025FY2024 | Change |
|---|---|---|
| Revenue | $9.89B$9.68B | +2.2% |
| Cost of Revenue | $2.40B$2.31B | +4.1% |
| Gross Profit | $7.49B$7.37B | +1.6% |
| SG&A Expenses | $2.43B$2.40B | +1.2% |
| Operating Expenses | $8.33B$7.77B | +7.3% |
| Interest Expense | $267.50M$250.30M | +6.9% |
| Net Income | $1.29B$1.63B | −20.8% |
| EPS (Basic) | $8.83$11.21 | −21.2% |
| EPS (Diluted) | $8.79$11.18 | −21.4% |
| Shares Outstanding (Basic) | 146.50M145.60M | +0.6% |
| Shares Outstanding (Diluted) | 147.10M145.90M | +0.8% |
05—Questions
Frequently Asked Questions
Why did Biogen's EPS decline sharply in 2025 even though revenue grew?
Diluted EPS fell 21.4% to $8.79 because costs rose faster than revenue. Acquired IPR&D, upfront and milestone expense jumped to $471.8 million from $61.5 million, litigation-related expense in other expense reached $139.5 million, a $104.9 million litigation-related charge hit royalty cost of sales, and a $52.9 million impairment was recorded on the Reata Plano lease. Lower gains and a higher effective tax rate of 16.9% also contributed.
How exposed is Biogen to the decline in MS revenue?
MS is still the largest franchise at $4.04 billion, but it fell 7.1% in 2025 as TECFIDERA faces multiple generics and TYSABRI faces a biosimilar. Management expects total MS revenue to keep declining in 2026, partly offset by VUMERITY growth. Growth in rare disease and the LEQEMBI collaboration is intended to offset this erosion over time.
What are the main upcoming regulatory and clinical catalysts?
Key near-term events include the April 3, 2026 PDUFA date for high-dose SPINRAZA in the U.S., the May 24, 2026 PDUFA date for LEQEMBI IQLIK weekly starting dose, and the January 2026 EC approval of high-dose SPINRAZA in the E.U. Clinical milestones include Phase 3 programs for felzartamab (AMR, IgAN, PMN), litifilimab (SLE, CLE), zorevunersen (Dravet) and salanersen, which is expected to begin Phase 3 in 2026.
Is Biogen's balance sheet and capital allocation position strong?
Cash, equivalents and marketable securities rose to $4.2 billion from $2.4 billion, and working capital increased to $5.6 billion. Total borrowings were stable at $6.3 billion after refinancing a $1.75 billion maturity. No share repurchases were made in 2025, leaving about $2.1 billion under the authorization. Management says existing funds, operating cash flow and financing access are sufficient for the foreseeable future, though operating cash flow fell to $2.2 billion in 2025.
What are the biggest legal and policy risks flagged in the filing?
Notable risks include a November 2025 judgment of about $124.3 million in the Genentech TYSABRI royalty case (under appeal), a German tax assessment of about $246.5 million that Biogen is contesting, antitrust suits from payers and pharmacies over TECFIDERA and VUMERITY contracts, and a Humana suit over patient assistance. On the policy side, IRA Medicare Part D redesign (about $90 million unfavorable in 2025), possible MFN pricing policies and the OBBBA could pressure U.S. pricing and reimbursement.
06—Continue