Business Overview
2022 Annual Meeting of Stockholders
Michel Vounatsos, Chief Executive Officer
June 15, 2022

Forward-looking statements
This presentation and the discussions during this Annual Meeting contain forward-looking statements, including statements made pursuant to the safe harbor provisions of the Private
Securities Litigation Reform Act of 1995, relating to: our strategy and plans; potential of, and expectations for, our commercial business and pipeline programs; capital allocation and investment
strategy; clinical development programs, clinical trials, and data readouts and presentations; risks and uncertainties associated with drug development and commercialization; regulatory
discussions, submissions, filings, and approvals and the timing thereof; the potential benefits, safety, and efficacy of our and our collaboration partners’ products and investigational therapies;
the anticipated benefits and potential of investments, collaborations, and business development activities; our future financial and operating results; 2022 financial guidance; plans relating toshare repurchases. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,”“plan,” “potential,” “possible,” “prospect,” “will,” “would,” and other words and terms of similar meaning. Drug development and commercialization involve a high degree of risk, and only a small
number of research and development programs result in commercialization of a product. Results in early-stage clinical trials may not be indicative of full results or results from later stage orlarger scale clinical trials and do not ensure regulatory approval. You should not place undue reliance on these statements or the scientific data presented.
These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements, including: our dependence on sales from ourproducts; the impact of the final NCD; uncertainty of long-term success in developing, licensing, or acquiring other product candidates or additional indications for existing products; risks anduncertainty as to whether the anticipated benefits of the transaction with Samsung Biologics can be achieved; uncertainty as to whether the anticipated benefits of the cost-reduction andproductivity measures can be achieved; failure to compete effectively due to significant product competition in the markets for our products; failure to successfully execute or realize theanticipated benefits of our strategic and growth initiatives; difficulties in obtaining and maintaining adequate coverage, pricing, and reimbursement for our products; our dependence oncollaborators, joint venture partners, and other third parties for the development, regulatory approval, and commercialization of products and other aspects of our business, which are outside of
our full control; the potential impact of the conflict in Ukraine; risks associated with current and potential future healthcare reforms; risks related to commercialization of biosimilars; failure toobtain, protect, and enforce our data, intellectual property, and other proprietary rights and the risks and uncertainties relating to intellectual property claims and challenges; the risk that
positive results in a clinical trial may not be replicated in subsequent or confirmatory trials or success in early stage clinical trials may not be predictive of results in later stage or large scaleclinical trials or trials in other potential indications; risks associated with clinical trials, including our ability to adequately manage clinical activities, unexpected concerns that may arise fromadditional data or analysis obtained during clinical trials, regulatory authorities may require additional information or further studies, or may fail to approve or may delay approval of our drugcandidates; the occurrence of adverse safety events, restrictions on use with our products, or product liability claims; risks relating to the distribution and sale by third parties of counterfeit orunfit versions of our products; risks relating to the use of social media for our business; risks relating to technology failures or breaches; risks relating to management and key personnel
changes, including attracting and retaining key personnel; failure to comply with legal and regulatory requirements; the risks of doing business internationally, including currency exchange rate
fluctuations; risks relating to investment in our manufacturing capacity; problems with our manufacturing processes; fluctuations in our effective tax rate; the direct and indirect impacts of theongoing COVID-19 pandemic on our business, results of operations, and financial condition; fluctuations in our operating results; risks related to investment in properties; the market, interest,and credit risks associated with our investment portfolio; risks relating to share repurchase programs; risks relating to access to capital and credit markets; risks related to indebtedness;change in control provisions in certain of our collaboration agreements; environmental risks; and any other risks and uncertainties that are described in other reports we have filed with the U.S.
Securities and Exchange Commission.

These statements are based on our current beliefs and expectations and speak only as of the date of this presentation. We do not undertake any obligation to publicly update any forwardlooking statements.
2Potential for renewed growth and value creation over time
GENETICNEURODEVELOPMENTAL

Achieved or Expected 2022 Milestone

PARKINSON’S DISEASE /MOVEMENT DISORDERS
LUPUS
STROKE
DEPRESSIONNEUROPSYCHIATRY

ALZHEIMER’SALZHEIMER’SBIOSIMILARSBIOSIMILAR LAUNCHESBIOSIMILAR LAUNCHESSPINAL MUSCULAR ATROPHY

NEUROMUSCULARNEUROMUSCULAR

MULTIPLE SCLEROSISMULTIPLE SCLEROSISMULTIPLE SCLEROSISMULTIPLE SCLEROSIS

Pre – 20162016 – 2021

2022 - 2025

2026-2030

BUSINESS DEVELOPMENT
DIGITAL HEALTH
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Continuing to lead and invest in multiple sclerosis
MS Patients

2021 Highlights• 2021 revenue of $7.1 billion, including OCREVUS

343k

346k

357k

342k

344k

royalties• VUMERITY continued to grow in U.S. and E.U.

• Intramuscular PLEGRIDY launched in both theU.S. and E.U.

• Subcutaneous TYSABRI launched in the E.U.

• Continuing to pursue new treatment options• InnoCare collaboration for an oral BTK inhibitor

20172018

2019

2020

AVONEX

PLEGRIDY

TYSABRITECFIDERA

2021
VUMERITY

4
Note: Patient numbers represent estimated ending patient count as of December 31st of each year.
4Continued leadership position in SMA
SPINRAZA Patients1

2021 Highlights• 2021 revenue of $1.9 billion
11,15011,720• Over 11,000 patients on therapy1• Proven efficacy across all patient types and a

10,000well characterized safety profile• Obtained reimbursement for SPINRAZA in China
6,220• Strengthening our competitive positioning inSMA, pursuing:– New ASO that may have the potential for

3,230

2017

2018

2019

2020

2021

extended dosing intervals– Additional analyses on real-world evidence
confirming efficacy in adults– Higher dose for even greater efficacy– Potential benefit following sub-optimal response
to competitor’s gene therapy and oral
treatments
1. Total patients across the post-marketing setting, the Expanded Access Program, and clinical trials.
55
ASO = antisense oligonucleotide

Expanding our biosimilars business
Biosimilars Patients

Commercialization of anti-TNFs in Europe• 2021 revenue of $831 million

1243k251k• Biogen contributed > €2.6 billion of healthcaresavings in 2021 across Europe2209k

Expanding biosimilar portfolio• BYOOVIZ (LUCENTIS® biosimilar) launched June
2022 in the U.S., with additional approvals in E.U.,
U.K., and Canada123k• BIIB800 (referencing ACTEMRA®) expected
regulatory filing in the U.S. and E.U. in 2H2275k• SB15 (EYLEA® biosimilar) currently in Phase 3• Collaboration to expand biosimilar pipeline with newpreclinical asset BIIB801 (referencing CIMZIA®)• Completed sale of equity stake in Samsung Bioepis
2017

2018

2019

2020

2021

joint venture
1.
2.

Includes ~116,000 patients on BENEPALI, ~95,000 patients on IMRALDI, and ~40,000 patients onFLIXABI.
6
6
Biogen estimate, data on file.

Key expected milestones for late-stage pipeline in 2022
2022 H1

2022 H2

Product Launches
VUMERITY – Ongoing ex-U.S. launches
BYOOVIZ – U.S. Launch (mid-year)

Regulatory Filings
Lecanemab* in Alzheimer’s disease – U.S. Filing+

Q2

Zuranolone* in MDD – U.S. Filing^

H2

BIIB800* referencing ACTEMRA® – U.S. and E.U. Filing

H2

Data Readouts
Zuranolone* – Phase 3 SKYLARK Study in PPD

Mid-year

Lecanemab* – Phase 3 in Alzheimer’s disease
BIIB104 – Phase 2 in CIAS

Fall
Mid-year

Note: lecanemab is being developed in collaboration with Eisai Co., Ltd. (Eisai); zuranolone is being developed in collaboration with Sage Therapeutics, Inc. (Sage)* Collaboration program; + Eisai responsible for lecanemab regulatory filing; ^ Sage responsible for zuranolone regulatory filing
MDD = major depressive disorder; PPD = postpartum depression; CIAS = cognitive impairment associated with schizophrenia Note: timeline is for illustrative purposes only777

Near-term operational priorities
Five priority actions intended to drive renewed revenue growthand value creation over time

Increasing
Focus on R&D
Prioritization

CostReduction andProductivity
Measures

Goal of maximizing the probability of success of R&D portfolio

Will be informed in part by key data readouts for lecanemab,
zuranolone, and BIIB104 expected in 2022

To further align costs with revenue base, while continuing to fundpromising pipeline and commercial opportunities

Note: lecanemab is being developed in collaboration with Eisai Co., Ltd.; zuranolone is being developed in collaboration with Sage Therapeutics, Inc.

8Near-term operational priorities

Executing on
Global GrowthOpportunities

Potential
Return toGrowth inBiosimilars

CapitalAllocation

Focus on key emerging markets, such as China and certain markets
in both Latin America and the Middle East
Continued launch of SPINRAZA and pursuing potential local businessdevelopment opportunities
Recently launched BYOOVIZ in the U.S., Biogen’s first biosimilar tolaunch in the U.S.
Three additional programs currently in development

Continue to focus deployment of cash towards incremental value
creation opportunities
Continue to return cash to shareholders through share repurchases
9Continuing to advance our ESG priorities
Progress Highlights

Transparency via Reporting

ENVIRONMENT• Completed 1st life cycle assessment (LCA) for 3 Biosimilars,
identifying ways to reduce product water, land and carbon footprints• Led on green chemistry as 14 labs achieved My Green Lab certification,
driving sustainability in scientific research• Set more ambitious goal for net zero supply chain by 2045 andsubmitted for approval by the Science Based Target initiative

SOCIAL• 100% of clinical trial studies initiated in 2021^ included a plan to recruit
underrepresented patients• Contributed grants, in-kind materials, volunteering and other support forUkraine humanitarian efforts• Engaged more than 61,000 students1, with focus on under-represented
children, in the 20 years since the inception of the Community LabGOVERNANCE• Formalized Board of Directors responsibility for ESG• Became early adopter of the new UN Global Compact reportingframework• Bolstered DE&I transparency with our 2021 DE&I report

2021 Year in Review report published in May 2022,
detailing ongoing leadership on material ESG issues.

Recognition for ESG leadership
JUST 100#36 on JUST Capital’s annual analysis ofcorporate ESG performance

Bloomberg Gender-Equality
Index
Member of 2021 GEI, committed to driving
accountability through data transparency

100 Most SustainableCorporations
Named to Corporate Knights’ 2022 list

Best Places to Work for
LGBTQ+ Equality
Named to Human Rights Campaign’s list
for 8th year in a row^ U.S. clinical trials in phases 1-4 led by Biogen’s Global Clinical Operations | 1 Total Community Lab students since inception in 2002

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Questions& Answers

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