Slide 1: Third Quarter 2025 Financial Results and Business Update
October 30, 2025 THIRD QUARTER 2025 FINANCIAL RESULTS AND BUSINESS UPDATE
Slide 2: Forward-Looking Statements
FORWARD-LOOKING STATEMENTS This presentation and discussions during this conference call contain forward-looking statements, relating to: our strategy and plans; potential of, and expectations for, our commercial business and pipeline programs; capital allocation and investment strategy; clinical de
Slide 3: Other Information
OTHER INFORMATION Non-GAAP Financial Information This presentation and the discussions during this conference call include certain financial measures that were not prepared in accordance with accounting principles generally accepted in the U.S. (GAAP), including adjusted net income, adjusted diluted
Slide 4: Biogen Call Participants
BIOGEN CALL PARTICIPANTS Christopher A. Priya Singhal, M.D., Viehbacher M.P.H. Alisha A. Alaimo Robin Kramer President and Chief Head of Development President and Head of Chief Financial Officer Executive Officer North America 4
Slide 5: Key Highlights
KEY HIGHLIGHTS Christopher A. Viehbacher President and Chief Executive Officer
Slide 6: During Q3 We Continued to Deliver Against Our Strategy for Long-Term Sustainable Growth
DURING Q3 WE CONTINUED TO DELIVER AGAINST OUR STRATEGY FOR LONG-TERM SUSTAINABLE GROWTH • Continued strength from launch products, delivering YoY growth of 67% in Q3 • Launch products YTD revenue growth more than offset MS decline YTD Commercial • LEQEMBI showed sustained sequential global demand gr
Slide 7: We Have Built an Innovative Pipeline with Compelling Commercial Potential
WE HAVE BUILT AN INNOVATIVE PIPELINE WITH COMPELLING COMMERCIAL POTENTIAL Phase 1 Phase 2 Phase 3 Lecanemab (Aβ mAb)* – Preclinical AD BIIB080 (tau ASO)^ – Early AD Neurology BIIB122 (LRRK2 inhibitor)* – Parkinson’s 5 Phase 3 NMEs and 10 Phase 3 or BIIB091 (peripheral BTK Inhibitor) – MS Phase 3-rea
Slide 8: Delivering on Our Plan to Return the Company to Long-Term Sustainable Growth
DELIVERING ON OUR PLAN TO RETURN THE COMPANY TO LONG-TERM SUSTAINABLE GROWTH WITH KEY DATA READOUTS NEXT YEAR Business Objective Biogen Today 1 1 2 Execute on new potential growth drivers 67% Revenue growth YoY3 $1.18B in trailing twelve-month revenue4 Maximize profitability of • Reallocated $250M o
Slide 9: Development Update
DEVELOPMENT UPDATE Priya Singhal, M.D., M.P.H. Head of Development
Slide 10: Focused Execution Has Positioned Us for Multiple Expected Milestones Over the Next 18 Months
FOCUSED EXECUTION HAS POSITIONED US FOR MULTIPLE EXPECTED MILESTONES OVER THE NEXT 18 MONTHS Study Starts Clinical Trial Readouts Regulatory Decisions • Felzartamab Phase 3 in IgAN • Salanersen Phase 1b interim in • Zuranolone in PPD SMA Now approved in the U.K. & E.U. • Felzartamab Phase 3 in PMN •
Slide 11: Advancing a Late-Stage, Registrational Pipeline While Building the Pre-POC Pipeline
ADVANCING A LATE-STAGE, REGISTRATIONAL PIPELINE WHILE BUILDING AND EXPANDING THE PRE-POC PIPELINE Regulatory Review in Pre-POC Pipeline Potentially Registrational Pipeline Certain Markets BIIB080 (tau ASO)^ Lecanemab (Aβ mAb)* Felzartamab Lecanemab (Aβ mAb)* BIIB142 (IRAK4 degrader)* – Early AD Prec
Slide 12: Delivering Differentiated Options for Alzheimer's Patients with LEQEMBI
DELIVERING DIFFERENTIATED OPTIONS FOR ALZHEIMER’S PATIENTS WITH LEQEMBI Expanding the convenience Exploring the potential benefits of LEQEMBI in the of LEQEMBI presymptomatic stages of Alzheimer’s disease • IV Initiation AHEAD 3–45 Study Potential landmark study in preclinical AD • IV Maintenance A3
Slide 13: A Period of Significant Registrational Readouts Beginning in 2026
A PERIOD OF SIGNIFICANT REGISTRATIONAL READOUTS BEGINNING IN 2026 REGISTRATIONAL PIPELINE TO SUPPORT OUR LONG-TERM GROWTH POTENTIAL DAPIROLIZUMAB PEGOL PHOENYCS FLY in SLE FELZARTAMAB PREVAIL in IgAN Neurology FELZARTAMAB Immunology TRANSPIRE in Late MVI Rare Disease# FELZARTAMAB PROMINENT in PMN FE
Slide 14: Commercial Update
COMMERCIAL UPDATE Alisha A. Alaimo President and Head of North America
Slide 15: Delivering LEQEMBI Growth & Expanding Treatment Options
DELIVERING LEQEMBI GROWTH & EXPANDING TREATMENT OPTIONS For Early Alzheimer's Disease • Q3 worldwide in-market sales of $121 million grew 82% YoY; U.S. in-market sales of $69 million increased 10% QoQ • U.S. prescriber base grew 14% QoQ as LEQEMBI continues to be #1 prescribed anti-amyloid therapy •
Slide 16: Activating the Community to Sustain Growth Trajectory
ACTIVATING THE COMMUNITY TO SUSTAIN GROWTH TRAJECTORY For Friedreich Ataxia • Q3 worldwide sales of $133 million, up 30% YoY and 2% QoQ • Now available in 34* countries with steady patient growth across geographies • U.S. seeing impact of focused investments on reaching community HCPs and slower pro
Slide 17: ZURZUVAE Continues Momentum with 19% QoQ Growth
ZURZUVAE CONTINUES MOMENTUM WITH 19% QOQ GROWTH For Postpartum Depression • Q3 U.S. sales of $55 million, up 151% YoY and 19% QoQ • Continued growth in patient demand • Performance sustains Q3 momentum on key metrics: o 19% increase in prescribers o 75% of prescriptions from repeat prescribers o 80%
Slide 18: Financial Update
FINANCIAL UPDATE Robin Kramer Chief Financial Officer
Slide 19: Third Quarter 2025 Key Financial Highlights
THIRD QUARTER 2025 KEY FINANCIAL HIGHLIGHTS Total Revenue GAAP Diluted EPS Non-GAAP Diluted EPS $2.53B 3% YoY $3.17 19% YoY $4.81 18% YoY Launch Products1 • $257M 67% YoY Performance • YTD increase in launch product revenue more than offset YTD decline in MS product revenue 27% YoY – Primarily due t
Slide 20: Third Quarter 2025 Revenue Highlights
THIRD QUARTER 2025 REVENUE HIGHLIGHTS ($ in Millions) Q3 2025 Q3 2024 YoY CC* Multiple sclerosis product revenue1 $1,062 $1,054 1% 0% Total rare disease revenue2 $533 $495 8% 6% Biosimilars revenue $197 $197 0% 0% Other product revenue3 $55 $24 129% 130% Revenue from anti-CD20 therapeutic progra
Slide 21: Third Quarter 2025 Key P&L Items
THIRD QUARTER 2025 KEY P&L ITEMS GAAP Non-GAAP ($ in Millions except EPS, Shares in Millions) Q3 2025 Q3 2024 Δ Y/Y ($ in Millions except EPS, Shares in Millions) Q3 2025 Q3 2024 Δ Y/Y Total Revenue $2,535 $2,466 3% Total Revenue $2,535 $2,466 3% GAAP Cost of Sales* $674 $639 (6%) Non-GAAP Cost of S
Slide 22: Expected Cash Flow Supports a Balance Sheet That Allows for Investment
EXPECTED CASH FLOW SUPPORTS A BALANCE SHEET THAT ALLOWS FOR INVESTMENT TO AUGMENT GROWTH Q3 2025 Cash Flow Balance Sheet* $1.3B Cash flow from operations $4.0B Cash and marketable securities $46M Capital expenditures $6.3B Debt $1.2B Free cash flow# $2.3B Net debt Note: Numbers may not foot due to r
Slide 23: Updated Guidance Reflects an Expected Stronger Business Outlook for Full Year 2025
UPDATED GUIDANCE REFLECTS AN EXPECTED STRONGER BUSINESS OUTLOOK FOR FULL YEAR 2025 Full Year 2025 Non-GAAP Diluted EPS Prior FY 2025 Guidance (July 2025) $15.50 to $16.00 Benefit from stronger business outlook +$0.25 Revised business outlook (October 2025) $15.75 - $16.25 Approx. impact from BD tran
Slide 24: Updated Key Considerations for Full Year 2025 Financial Guidance
UPDATED KEY CONSIDERATIONS FOR FULL YEAR 2025 FINANCIAL GUIDANCE Total Revenue P&L • Increased expected full year 2025 total revenue to be • Expect Q4 2025 OpEx to be ~$1.1B, driven by seasonality of approximately flat to increasing 1%, at constant currency, versus spend and additional investments t
Slide 25: Questions & Answers
QUESTIONS & ANSWERS
Slide 26: Appendix
APPENDIX
Slide 27: Consolidated Statement of Income
CONSOLIDATED STATEMENT OF INCOME (unaudited, in millions, except per share amounts) 27
Slide 28: Consolidated Balance Sheets
CONSOLIDATED BALANCE SHEETS (unaudited, in millions) 28
Slide 29: Product Revenue (U.S. and Rest of World) & Total Revenue
PRODUCT REVENUE (U.S. AND REST OF WORLD) & TOTAL REVENUE (unaudited, in millions) 29
Slide 30: GAAP to Non-GAAP Reconciliation
GAAP TO NON-GAAP RECONCILIATION (unaudited, in millions) Use of Non-GAAP Financial Measures We supplement our GAAP consolidated financial statements and GAAP financial measures with other financial measures, such as adjusted net income, adjusted diluted earnings per share, revenue change at constant
Slide 31: GAAP to Non-GAAP Reconciliation (Continued)
GAAP TO NON-GAAP RECONCILIATION Continued (unaudited, in millions, except effective tax rates & per share amounts) 31
Slide 32: GAAP to Non-GAAP Reconciliation: Revenue Change at Constant Currency
GAAP TO NON-GAAP RECONCILIATION Continued Revenue Change at Constant Currency vs Q3 2024 (unaudited) 32
Slide 33: GAAP to Non-GAAP Reconciliation: Free Cash Flow
GAAP TO NON-GAAP RECONCILIATION Continued Free Cash Flow (unaudited, in millions) 33
Slide 34: LEQEMBI: Continued Momentum with Global Launch Showing Increased Sequential In-Market Demand
LEQEMBI: CONTINUED MOMENTUM WITH GLOBAL LAUNCH SHOWING INCREASED SEQUENTIAL IN-MARKET DEMAND $180 M $160 M $140 M China demand satisfied from inventory and not reported as $120 M sales $100 M $80 M $60 M $40 M $20 M $0 M Q1 2024 Q2 2024 Q3 2024 Q4 2024 Q1 2025 Q2 2025 Q3 2025 US Ex-US China Stocking
Slide 35: LEQEMBI Collaboration Accounting
LEQEMBI COLLABORATION ACCOUNTING Revenue • Eisai records 100% of net product revenue globally (Commercial) • Biogen’s 50% share of LEQEMBI revenue, net and cost of sales (including royalties) is recorded in “Alzheimer's collaboration revenue” Product revenue, net Less cost of sales Less royalties Al
Slide 36: ZURZUVAE Collaboration Accounting
ZURZUVAE COLLABORATION ACCOUNTING Commercial • Biogen reflects net revenue on sales of ZURZUVAE and records Biogen’s cost of sales Economics and SG&A in their respective line items. Biogen shares 50% of the profit or loss with (U.S.) Supernus Pharmaceuticals, which is recognized in the “collaboratio