• Biogen is like Novo Nordisk for neurological diseases.
• Biogen is the Gilead Sciences for brain and nerve disorders.
• Biogen is a specialized Eli Lilly for conditions like MS and Alzheimer's.

• Spinraza (nusinersen): A treatment for Spinal Muscular Atrophy (SMA), a rare and often fatal genetic disease that causes muscle weakness and wasting.
• Tecfidera (dimethyl fumarate): An oral treatment used to reduce relapses and slow the progression of disability in people with relapsing forms of Multiple Sclerosis (MS).
• Tysabri (natalizumab): A monoclonal antibody used to treat relapsing forms of Multiple Sclerosis (MS) and Crohn's disease.
• Vumerity (diroximel fumarate): An oral capsule used to treat relapsing forms of Multiple Sclerosis (MS), offering a different formulation with potentially improved gastrointestinal tolerability compared to Tecfidera.
• Leqembi (lecanemab): A monoclonal antibody co-developed with Eisai, indicated to reduce amyloid-beta plaques in the brains of patients with early Alzheimer's disease.
• Qalsody (tofersen): An antisense oligonucleotide approved for the treatment of amyotrophic lateral sclerosis (ALS) in adults who have a mutation in the superoxide dismutase 1 (SOD1) gene.

Biogen (BIIB) - Major Customers

Biogen primarily sells its pharmaceutical products to major wholesale distributors, who then distribute the medicines to pharmacies, hospitals, and other healthcare providers. Therefore, Biogen's major customers are other companies rather than individuals.

According to Biogen's public filings, the following major wholesale distributors individually accounted for 10% or more of its total consolidated revenues in recent years:

• AmerisourceBergen Corporation (NYSE: ABC)
• Cardinal Health, Inc. (NYSE: CAH)
• McKesson Corporation (NYSE: MCK)

Christopher A. Viehbacher, President and Chief Executive Officer

Christopher A. Viehbacher joined Biogen as President and Chief Executive Officer and a member of the Board of Directors in November 2022. He has extensive international experience, having spent 20 years with GlaxoSmithKline before serving as global CEO of Sanofi for six years. During his tenure at Sanofi, Viehbacher strengthened and diversified its R&D pipeline, oversaw the acquisition of Genzyme, and delivered significant value to shareholders. More recently, Viehbacher co-founded Gurnet Point Capital, a Cambridge-based healthcare investment fund, which has led to the creation and development of many innovative companies. He is the Managing Partner of Gurnet Point Capital, a healthcare venture capital and private equity fund backed by the Bertarelli family. He has also chaired or been a member of the board of a number of entrepreneurial biotechnology companies.

Robin Kramer, Executive Vice President and Chief Financial Officer

Robin Kramer is the Executive Vice President and Chief Financial Officer at Biogen, a role she assumed in March 2025. She joined Biogen in 2018 as Vice President, Chief Accounting Officer, and later served as Senior Vice President, Chief Accounting Officer. Prior to her time at Biogen, Ms. Kramer served as the Senior Vice President and Chief Accounting Officer at Hertz Global Holdings from 2014 to 2018. Her earlier career included roles as Chief Accounting Officer of Fisher Scientific International and Director, External Reporting, Accounting and Control for The Gillette Company. Ms. Kramer also held partner positions in public accounting firms such as Deloitte & Touche LLP, Ernst & Young LLP, and Arthur Andersen LLP. She currently chairs the board and audit committee of Armata Pharmaceuticals.

Susan H. Alexander, Chief Legal Officer

Susan H. Alexander has served as the Executive Vice President and Chief Legal Officer and Secretary of Biogen since January 2017. Before joining Biogen, she held positions as Senior Vice President, General Counsel, and Corporate Secretary at PAREXEL International Corporation from 2003 to January 2006, and as General Counsel at IONA Technologies and Cabot Corporation.

Ginger Gregory, Ph. D., Chief Human Resources Officer

Ginger Gregory, Ph. D., serves as Biogen's Executive Vice President and Chief Human Resources Officer.

Rachid Izzar, Head of Global Product Strategy & Commercialization

Rachid Izzar is the Executive Vice President and Head of Global Product Strategy & Commercialization at Biogen.

1. Loss of Market Share and Generic/Biosimilar Competition for Established Drugs: Biogen is experiencing a rapid decline in market share within its historically dominant multiple sclerosis (MS) segment. This is largely due to increased competition from other pharmaceutical companies, such as Roche with Ocrevus and Novartis with Kesimpta. The market has also been flooded with generics, particularly impacting sales of Tecfidera, which has been a major source of cash flow. This competition and patent expirations continue to limit opportunities for sales growth and have contributed to declining revenue.
2. Uncertainty and Slow Uptake of New Products: The company's ability to offset revenue declines depends heavily on the successful launch and adoption of new products, particularly in the Alzheimer's disease market. Biogen's prior Alzheimer's drug, Aduhelm, faced significant commercial failure due to skepticism from the medical community regarding its effectiveness, a high price tag, and limited insurance coverage, leading to substantial financial and personnel losses. While Leqembi is a newer Alzheimer's treatment, its sales have grown slowly, and it has encountered regulatory setbacks in Europe, indicating continued challenges in new product commercialization.
3. Pipeline Dependency and R&D Failures: Biogen has a history of high-profile research and development (R&D) failures, including multiple gene therapy trials and earlier iterations of Alzheimer's drugs. The company's future growth is highly dependent on the success of its current pipeline, and setbacks in key programs can significantly impact its long-term prospects and investor confidence, especially given the substantial R&D investments required.

One clear emerging threat to Biogen is the potential market entry and competitive impact of **Donanemab**, Eli Lilly's investigational Alzheimer's disease treatment. Donanemab, similar to Biogen and Eisai's Leqembi, targets amyloid plaques in the brain and has demonstrated positive results in Phase 3 clinical trials. With Donanemab awaiting regulatory approval, its potential launch represents a direct, head-to-head competitor in the nascent and highly anticipated market for disease-modifying Alzheimer's therapies. The introduction of another effective treatment could significantly fragment the market share for anti-amyloid drugs, impacting the revenue potential and patient access for Leqembi, which is a key growth driver for Biogen.

Biogen's main products target neurological and neurodegenerative diseases, including multiple sclerosis, spinal muscular atrophy, and Alzheimer's disease. The addressable markets for these products vary by drug and region.

Leqembi (Lecanemab) - Alzheimer's Disease

• The global sales for Leqembi are projected to reach $12.9 billion by 2028.
• The U.S. market is expected to contribute $7.7 billion to Leqembi's sales between 2023 and 2028.
• Another forecast estimates Leqembi will generate $4.2 billion globally by 2030.
• The overall global Alzheimer's disease market was valued at $1.9 billion in 2023 and is projected to reach $17 billion across eight major markets by 2033.

Tysabri (Natalizumab) - Multiple Sclerosis and Crohn's Disease

• The global market size for Tysabri is projected to grow from $2.5 billion in 2023 to approximately $4.8 billion by 2032.
• Other estimates place the global Tysabri market at $2.30 billion in 2023, projected to reach $3.24 billion by 2030.
• North America holds the largest market share for Tysabri.
• Tysabri's global revenues were approximately $1.9 billion in 2023.

Spinraza (Nusinersen) - Spinal Muscular Atrophy (SMA)

• Spinraza's global revenues reached $1.7 billion in 2023.
• The global spinal muscular atrophy market was valued at $3.0 billion in 2023 and is expected to reach $13.0 billion by 2034.
• Another estimate for the global SMA market is $27.5 billion by 2033.
• North America was the largest region in the Spinraza market in 2024.

Qalsody (Tofersen) - Amyotrophic Lateral Sclerosis (ALS) with SOD1 mutations

• Qalsody's peak sales potential is estimated to be around $300 million globally.
• Biogen reported $32.4 million in Qalsody revenue for 2024.
• The global amyotrophic lateral sclerosis (ALS) market was valued at $494.1 million in 2023 and is projected to reach $715.4 million by 2034.
• The global ALS therapeutics market was valued at $1.01 billion in 2023 and is projected to reach $1.80 billion by 2032.

Tecfidera (Dimethyl Fumarate) - Multiple Sclerosis

• Tecfidera's sales declined from a peak of $4.4 billion in 2019 to $1.4 billion in 2022 due to generic competition.
• U.S. sales for Tecfidera were $417.7 million in 2022.
• The broader global dimethyl fumarate (DMF) market, which includes generics, was valued at approximately $2.34 billion in 2024 and is projected to reach around $3.82 billion by 2034.
• North America represented the largest regional market for DMF in 2024, valued at approximately $1.05 billion. Europe held the second-largest share, valued at $830 million in 2024.

Vumerity (Diroximel Fumarate) - Multiple Sclerosis

• Vumerity's sales were almost $500 million in the first nine months of 2025.
• Earlier consensus estimates projected Vumerity sales at a modest $111 million in 2024.
• The global multiple sclerosis drugs market was valued at $21.33 billion in 2023 and is projected to grow to $38.94 billion by 2032.

Biosimilars

• The global biosimilars market was valued at $20.44 billion in 2022 and is projected to grow to $73.03 billion by 2030.
• Another forecast estimates the global biosimilars market at $34.43 billion in 2024, predicted to increase to approximately $175.99 billion by 2034.
• Europe dominated the global biosimilars market with a 50.44% share in 2022.
• The North America biosimilars market accounted for $7.51 billion in 2024 and is expected to reach around $37.64 billion by 2034.
• Biogen's biosimilars contributed $198 million in the second quarter (recent, year not specified).

Biogen (BIIB) is expected to drive future revenue growth over the next 2-3 years through several key factors:

• Growth of Recently Launched Products: Biogen anticipates significant revenue growth from its recently launched products, including LEQEMBI for Alzheimer's disease, SKYCLARYS for Friedreich's ataxia, and ZURZUVAE for postpartum depression. These products have shown strong sequential and year-over-year revenue increases, with LEQEMBI global sales reaching $121 million in Q3 2025, an 82% growth compared to Q3 2024. SKYCLARYS is seeing increased demand and geographic expansion, while ZURZUVAE also posted robust revenue growth.
• Advancements and Approvals from the Pipeline: The company is heavily investing in its pipeline, with plans to initiate five Phase III studies in 2025. Potential FDA approvals and data readouts from its late-stage programs, such as litifilimab for systemic lupus erythematosus (expected readouts in 2026), salanersen, felzartamab, and a high-dose SPINRAZA (PDUFA in April 2026), are expected to influence future growth. Biogen is also advancing its immunology strategy with new early-stage programs like the IRAK4 degrader for autoimmune diseases.
• Geographic and Market Expansion: Biogen is focused on expanding the reimbursement and commercial launches of its key products, particularly LEQEMBI and SKYCLARYS, into additional international markets. The company aims to secure broader access and physician adoption globally for these therapies. ZURZUVAE also received approval in the EU in September, contributing to potential market expansion.
• Strategic Collaborations and Acquisitions: Biogen leverages strategic collaborations, such as its partnership with Eisai for the development and commercialization of LEQEMBI. These collaborations enable shared risk and synergistic growth opportunities. Additionally, strategic acquisitions like that of Alcyone Therapeutics in September 2025 are part of the company's long-term growth strategy by enhancing its pipeline and capabilities.

Share Repurchases

• Biogen authorized a $5.0 billion share repurchase program in October 2020, which has no expiration date and was expected to be executed within five years.
• The company repurchased approximately $1.25 billion in shares during the third quarter of 2020, completing a previously authorized program, and an additional $750 million in 2022.
• No common stock repurchases were made in 2023 and 2024, and approximately $2.1 billion remained available under the 2020 Share Repurchase Program as of March 31, 2025.

Share Issuance

• Biogen’s Board of Directors approved the 2024 Omnibus Equity Plan and the 2024 Employee Stock Purchase Plan, which allow for future share issuances.
• Shares outstanding remained relatively stable over the period, with approximately 146 million shares outstanding at the end of 2024 and 147 million in Q3 2025.
• Share issuances are primarily related to the company's share-based compensation plans for employees.

Outbound Investments

• In March 2020, Biogen acquired BIIB118 (CK1 inhibitor), a novel CNS-penetrant small molecule from Pfizer Inc. for the potential treatment of psychiatric and neurological diseases.
• Biogen acquired Reata Pharmaceuticals, Inc. in July 2023, integrating SKYCLARYS, a treatment for Friedreich ataxia, into its product portfolio.
• In May 2024, Biogen acquired Human Immunology Biosciences (HIBio) for $1.15 billion, enhancing its immunology pipeline with felzartamab for immune-mediated diseases.

Capital Expenditures

• Capital expenditures fluctuated over the last five years, from approximately $424.8 million in 2020 to about $153.7 million in 2024.
• Expected capital expenditures for 2025 are forecasted to be between $177.3 million and $184.6 million.
• Future capital investments include an additional $2 billion in Biogen's North Carolina manufacturing footprint in Research Triangle Park over the next few years to expand antisense oligonucleotide (ASO) capabilities, establish multi-platform fill-finish, and modernize manufacturing technologies. The company also plans additional investments in R&D, primarily for rare diseases, and to support launch products in 2025.