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Item 1. Business

2024-02-14 compared with 2023-02-15 · 498 added, 459 removed, 758 unchanged (56% of the section changed)

Biogen is a global biopharmaceutical company focused on discovering, developing and delivering innovative therapies for people living with serious and complex diseases worldwide.

We have a broad portfolio of medicines to treat multiple sclerosis (MS), have introduced the first approved treatment for spinal muscular atrophy (SMA) and co-developed two treatments to address a defining pathology of Alzheimer’s disease.

We are focused on advancing our pipeline in neurology, neuropsychiatry, specialized immunology and rare diseases.

We have a broad portfolio of medicines to treat MS, have introduced the first approved treatment for SMA, co-developed treatments to address a defining pathology of Alzheimer’s disease and launched the first approved treatment to target a genetic cause of ALS.

Through our 2023 acquisition of Reata we market the first and only drug approved in the U.S.

for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older.

We are focused on advancing our pipeline in neurology, specialized immunology and rare diseases.

We support our drug discovery and development efforts through internal research and development programs and external collaborations.

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SPINRAZA for the treatment of SMA;

ADUHELM for the treatment of Alzheimer's disease;

SKYCLARYS for the treatment of Friedreich's Ataxia;

QALSODY for the treatment of ALS;

and FUMADERM for the treatment of severe plaque psoriasis.

We also collaborate with Eisai Co., Ltd.

(Eisai) on the commercialization of LEQEMBI for the treatment of Alzheimer's disease, which was granted accelerated approval by the U.S.

Food and Drug Administration (FDA) in January 2023.

We have certain business and financial rights with respect to RITUXAN for the treatment of non-Hodgkin's lymphoma, chronic lymphocytic leukemia (CLL) and other conditions;

We also have collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease and Sage on the commercialization of ZURZUVAE for the treatment of PPD and we have certain business and financial rights with respect to RITUXAN for the treatment of non-Hodgkin's lymphoma, CLL and other conditions;

RITUXAN HYCELA for the treatment of non-Hodgkin's lymphoma and CLL;

GAZYVA for the treatment of CLL and follicular lymphoma;

OCREVUS for the treatment of primary progressive MS (PPMS) and relapsing MS (RMS);

LUNSUMIO (mosunetuzumab), which was granted accelerated approval in the U.S.

during the fourth quarter of 2022 for the treatment of relapsed or refractory follicular lymphoma;

glofitamab, an investigational bispecific antibody for the potential treatment of non-Hodgkin's lymphoma;

and have the option to add other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, Inc.

(Genentech), a wholly-owned member of the Roche Group.

In addition to continuing to invest in new potential innovation in MS and SMA we are advancing our mid-to-late stage programs including zuranolone for major depressive disorder (MDD) and postpartum depression (PPD), BIIB080 for Alzheimer's disease, tofersen for amyotrophic lateral sclerosis (ALS) and both litifilimab and dapirolizumab pegol for certain forms of lupus.

We also commercialize biosimilars of advanced biologics including BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE, in certain countries in Europe, as well as BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, in the U.S.

We continue to develop potential biosimilar products including BIIB800, a proposed tocilizumab biosimilar referencing ACTEMRA, and SB15, a proposed aflibercept biosimilar referencing EYLEA.

For additional information on our collaboration arrangements, please read Note 19, Collaborative and Other Relationships , to our consolidated financial statements included in this report.

OCREVUS for the treatment of PPMS and RMS;

LUNSUMIO for the treatment of relapsed or refractory follicular lymphoma;

COLUMVI, a bispecific antibody for the treatment of non-Hodgkin's lymphoma;

and have the option to add other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, a wholly-owned member of the Roche Group.

We commercialize a portfolio of biosimilars of advanced biologics including BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE, in certain countries in Europe, as well as BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, in the U.S.

and certain international markets.

We also have exclusive rights to commercialize TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA.

We continue to develop potential biosimilar product SB15, a proposed aflibercept biosimilar referencing EYLEA.

In February 2023 we announced that we are exploring strategic options for our biosimilars business.

KEY BUSINESS DEVELOPMENTS

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DEVELOPMENTS IN KEY COLLABORATIVE RELATIONSHIPS

Eisai Collaboration Agreements

LEQEMBI (lecanemab) Collaboration Agreement

In January 2023 we and Eisai announced that the FDA granted accelerated approval of LEQEMBI, an anti-amyloid antibody for the treatment of Alzheimer's disease.

Additionally, in January 2023 we and Eisai announced the completed submission of a supplemental Biologics License Application (BLA) to the FDA for traditional approval of LEQEMBI.

In January 2023 the European Medicines Agency (EMA) accepted for review the Marketing Authorization Application (MAA) for lecanemab.

In January 2023 Eisai completed the submission of a MAA to the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan for lecanemab, and was granted Priority Review by the Japanese Ministry of Health, Labor and Welfare.

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In December 2022 Eisai initiated a rolling submission of a BLA to the National Medicinal Products Administration (NMPA) of China for the approval of lecanemab.

In March 2022 we extended our supply agreement with Eisai related to LEQEMBI from five years to ten years for the manufacture of LEQEMBI drug substance.

ADUHELM Collaboration Agreement

On March 14, 2022, we amended our ADUHELM Collaboration Agreement with Eisai.

As of the amendment date, we have sole decision making and commercialization rights worldwide on ADUHELM, and beginning January 1, 2023, Eisai receives only a tiered royalty based on net sales of ADUHELM, and no longer participates in sharing ADUHELM's global profits and losses.

Eisai's share of development, commercialization and manufacturing expense was limited to $335.0 million for the period from January 1, 2022 to December 31, 2022, which was achieved as of December 31, 2022.

Once this limit was achieved, we became responsible for all ADUHELM related costs.

For additional information on our collaboration arrangements with Eisai, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

Zuranolone (BIIB125)

In June 2022 we and our collaboration partner Sage Therapeutics, Inc.

(Sage) announced that the Phase 3 SKYLARK study of zuranolone, for the potential treatment of MDD and PPD, met its primary and all key secondary endpoints.

In December 2022 we and Sage completed the rolling submission of a New Drug Application (NDA) to the FDA for the approval of zuranolone for the potential treatment of MDD and PPD.

This submission completes the NDA filing initiated earlier in 2022.

In February 2023 the FDA accepted the NDA and granted Priority Review for zuranolone, with a Prescription Drug User Fee Act (PDUFA) action date of August 5, 2023.

LEQEMBI (lecanemab)

United States

In July 2023 the FDA granted traditional approval of LEQEMBI, an anti-amyloid antibody for the treatment of Alzheimer's disease, which was previously granted accelerated approval by the FDA in January 2023.

Following the FDA's traditional approval of LEQEMBI, CMS confirmed broader coverage of LEQEMBI.

Additionally, in March 2023 Eisai announced that the U.S.

Veteran's Health Administration will be providing coverage of LEQEMBI to veterans living with early stages of Alzheimer's disease.

Rest of World

Key developments related to LEQEMBI (lecanemab) in rest of world markets during 2023 consisted of the following:

• In January 2024 we and Eisai announced that the SAG will convene at the request of the CHMP to discuss the MAA of lecanemab that is currently under review by the EMA.

The meeting of the SAG is expected to take place during the first quarter of 2024 and the EC decision for the MAA of lecanemab is expected during the first half of 2024.

• In January 2024 the NMPA approved LEQEMBI in China, with an expected launch date in 2024.

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• In December 2023 we and Eisai announced that LEQEMBI intravenous infusion was launched in Japan.

• In September 2023 the Japanese Ministry of Health, Labor and Welfare approved LEQEMBI in Japan.

• In January 2023 the EMA accepted for review the MAA for lecanemab.

• In February 2023 the BLA for lecanemab was granted Priority Review by the NMPA of China.

• In May 2023 we and Eisai announced the submission of a MAA for lecanemab to the U.K.

MHRA in Great Britain, which has been designated by the MHRA for the Innovative Licensing and Access Pathway.

Additionally, in May 2023 Health Canada accepted for review the NDS for lecanemab.

• In June 2023 we and Eisai announced the submission of a MAA for lecanemab to the Ministry of Food and Drug Safety in South Korea.

ZURZUVAE (zuranolone)

In August 2023 the FDA approved ZURZUVAE for adults with PPD, pending DEA scheduling, which was completed in October 2023.

Upon approval, ZURZUVAE for PPD became the first and only oral, once-daily, 14-day treatment that can provide rapid improvements in depressive symptoms by day 15 for women with PPD.

ZURZUVAE for PPD became commercially available in the U.S.

during the fourth quarter of 2023.

Additionally, the FDA issued a CRL for the NDA for zuranolone in the treatment of adults with MDD.

The CRL stated that the application did not provide substantial evidence of effectiveness to support the approval of zuranolone for the treatment of MDD and that an additional study or studies would be needed.

We and Sage are continuing to seek feedback from the FDA and evaluating next steps.

For additional information on our collaboration arrangement with Sage, please read Note 19, Collaborative and Other Relationships , to our consolidated financial statements included in this report.

LUNSUMIO (mosunetuzumab)

In January 2022 we exercised our option with Genentech to participate in the joint development and commercialization of LUNSUMIO (mosunetuzumab), a bispecific antibody for the treatment of relapsed or refractory follicular lymphoma.

In connection with this exercise, we recorded a $30.0 million option exercise fee payable to Genentech in December 2021.

In December 2022 Genentech announced that the FDA granted accelerated approval of LUNSUMIO, which was also approved by the European Commission (EC) in June 2022.

In December 2022 we reached an agreement with Genentech related to the commercialization and sharing of economics for glofitamab, an investigational T-cell engaging bispecific antibody targeting CD20 and CD3 for the potential treatment of B-cell non-Hodgkin's lymphoma.

For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships , to our consolidated financial statements included in this report.

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Other Collaborative Relationships

Alcyone Therapeutics

In December 2022 we entered into a license and collaboration agreement with Alcyone Therapeutics (Alcyone) to jointly develop the ThecaFlex DRx™ System, an implantable medical device intended for subcutaneous delivery of antisense oligonucleotide (ASO) therapies with a goal of improving the patient treatment experience and accessibility for people suffering from neurological disorders, such as SMA and ALS.

Under the terms of this collaboration, we and Alcyone will jointly develop the ThecaFlex DRx™ System and Alcyone will be solely responsible for its manufacture and commercialization.

In connection with this transaction, we made an upfront payment of $10.0 million to Alcyone.

BUSINESS COMBINATIONS

REATA ACQUISITION

On September 26, 2023, we completed the acquisition of all of the issued and outstanding shares of Reata, a biopharmaceutical company focused on developing therapeutics that regulate cellular metabolism and inflammation in serious neurologic diseases.

As a result of this transaction we acquired SKYCLARYS (omaveloxolone), the first and only drug approved in the U.S.

for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older, as well as other clinical and preclinical pipeline programs.

Under the terms of this acquisition, we paid Reata shareholders $172.50 in cash for each issued and outstanding Reata share, which totaled approximately $6.6 billion.

In addition, we agreed to pay approximately $983.9 million in cash for Reata's outstanding equity awards, inclusive of employer taxes, of which approximately $590.5 million was attributable to pre-acquisition services and is therefore reflected as a component of total purchase price paid.

Of the $983.9 million paid to Reata's equity award holders, we recognized approximately $393.4 million as compensation attributable to the post-acquisition service period, of which $196.4 million was recognized as a charge to selling, general and administrative expense with the remaining $197.0 million as a charge to research and development expense within our consolidated statements of income for the year ended December 31, 2023.

These amounts were associated with the accelerated vesting of stock options and RSUs previously granted to Reata employees that required no future services to vest.

For additional information on our acquisition of Reata, please read Note 2, Acquisitions , to our consolidated financial statements included in this report.

OTHER KEY DEVELOPMENTS

QALSODY (tofersen)

In April 2023 the FDA approved QALSODY for the treatment of ALS in adults who have a mutation in the SOD1 gene.

This indication is approved under accelerated approval based on reduction in plasma neurofilament light chain observed in patients treated with QALSODY.

Continued approval for this indication may be contingent upon verification of clinical benefit in confirmatory trial(s).

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protection for its pediatric indication, we believe that TECFIDERA is entitled to regulatory marketing protection in the E.U.

until at least February 2, 2025, and are seeking to enforce this protection.

In December 2023, the EC revoked all centralized marketing authorizations for generic versions of TECFIDERA.

As of December 31, 2023, some of the TECFIDERA generics have not yet fully exited some E.U.

markets and we expect removal of all generics from the market will take additional time.

We are closely monitoring this situation and working to enforce our legal right to market protection.

In addition, we will continue to enforce our EP 2 653 873 patent related to TECFIDERA, which expires in 2028.

CORPORATE MATTERS

Samsung Bioepis - Biogen's Joint Venture with Samsung BioLogics

In April 2022 we completed the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics Co., Ltd.

(Samsung BioLogics).

Under the terms of this transaction, we received approximately $1.0 billion in cash at closing and expect to receive approximately $1.3 billion in cash to be deferred over two payments of approximately $812.5 million due at the first anniversary and approximately $437.5 million due at the second anniversary of the closing of this transaction.

As part of this transaction, we are also eligible to receive up to an additional $50.0 million upon the achievement of certain commercial milestones.

Our policy for contingent payments of this nature is to recognize the payments in the period that they become realizable, which is generally the same period in which the payments are earned.

For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 3, Dispositions, to our consolidated financial statements included in this report.

2022 Cost Saving Initiatives

In December 2021 and May 2022 we announced our plans to implement a series of cost-reduction measures that when completed we expect may yield approximately $1.0 billion in expense savings.

These savings are being achieved through a number of initiatives, including reductions to our workforce, the substantial elimination of our commercial ADUHELM infrastructure, the consolidation of certain real estate locations and operating efficiency gains across our selling, general and administrative and research and development functions.

Under these initiatives, we estimate we will incur total restructuring charges of approximately $131.0 million, primarily related to severance.

These amounts were substantially incurred during 2022.

As of December 31, 2022, approximately $35.9 million remained in our restructuring reserve and payments are expected to be made through 2026.

For additional information on our 2022 cost saving initiatives, please read Note 4, Restructuring , to our consolidated financial statements included in this report.

125 Broadway Sale and Leaseback Transaction

In September 2022 we completed the sale of our building and land parcel located at 125 Broadway, Cambridge, MA (125 Broadway) for an aggregate sales price of approximately $603.0 million, which is inclusive of a $10.8 million tenant allowance.

Simultaneously, with the close of this transaction we leased back the building for a term of approximately 5.5 years.

For additional information on our 125 Broadway sale and leaseback transaction, please read Note 11, Property, Plant and Equipment and Note 12, Leases , to our consolidated financial statements included in this report.

FIT FOR GROWTH

In 2023 we initiated additional cost saving measures as part of our Fit for Growth program to reduce operating costs, while improving operating efficiency and effectiveness.

The Fit for Growth program is expected to generate approximately $1.0 billion in gross operating expense savings and $800.0 million in net operating expense savings by 2025, some of which will be reinvested in various initiatives.

The Fit for Growth program is currently estimated to include net headcount reductions of approximately 1,000 employees and we expect to incur restructuring charges ranging from approximately $260.0 million to $280.0 million.

For additional information on our Fit for Growth program, please read Note 4, Restructuring , to our consolidated financial statements included in this report.

MANAGEMENT CHANGES

• In November 2022 we announced the appointment of Christopher A.

Viehbacher as President and Chief Executive Officer.

• In February 2022 we announced the appointment of Nicole Murphy as Executive Vice President, Pharmaceutical Operations and Technology.

• In January 2023 we announced the appointment of Priya Singhal as Executive Vice President, Head of Development.

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• In September 2023 we announced the appointment of Jane Grogan, Ph.D., as Executive Vice President, Head of Research.

• In April 2023 we announced the appointment of Adam Keeney, as Executive Vice President, Head of Corporate Development.

BOARD OF DIRECTORS UPDATE

• In June 2022 Nancy Leaming and Brian Posner retired from our Board of Directors.

• In November 2022 Christopher A.

Viehbacher joined our Board of Directors.

• In November 2023 we announced Monish Patolawala will be joining our Board of Directors, effective January 1, 2024.

• In June 2023 Susan Langer joined our Board of Directors.

• In June 2023 Caroline Dorsa succeeded Stelios Papadopoulos as Chair of our Board of Directors.

• In June 2023 Stelios Papadopoulos, Alexander J.

Denner, Ph.D., William D.

Jones and Richard C.

Mulligan, Ph.D., departed from our Board of Directors.

For additional information on our executive officers, please read the subsection entitled "Information about our Executive Officers" included in this report.

PRODUCT AND PIPELINE DEVELOPMENTS

Multiple Sclerosis and Neuroimmunology

TECFIDERA (dimethyl fumerate)

• In June 2022 the European Patent Office (EPO) granted a patent that expires in February 2028 related to TECFIDERA.

• In October 2022 the Advocate General of the Court of Justice of the European Union (CJEU) issued a nonbinding advisory opinion in Biogen's favor relating to regulatory data protection for TECFIDERA.

This opinion recommends that the CJEU set aside the earlier judgement of the European General Court annulling the EMA's decision not to validate an application to market a generic version of TECFIDERA.

Alzheimer's Disease and Dementia

ALZHEIMER'S DISEASE

LEQEMBI (lecanemab )

• In January 2023 we and Eisai announced that the FDA granted accelerated approval of LEQEMBI, an anti-amyloid antibody for the treatment of Alzheimer's disease.

Additionally, in January 2023 we and Eisai announced the completed submission of a supplemental BLA to the FDA for traditional approval of LEQEMBI.

• In September 2022 we and Eisai announced positive topline results from the confirmatory Phase 3 CLARITY Alzheimer's disease study of LEQEMBI.

LEQEMBI met the primary endpoint and all key secondary endpoints with highly statistically significant results.

• In November 2022 Eisai presented full results from the confirmatory Phase 3 CLARITY Alzheimer's disease study of LEQEMBI at the 2022 Clinical Trials on Alzheimer's Disease conference.

• In November 2022 The New England Journal of Medicine published full results from the confirmatory Phase 3 CLARITY Alzheimer's disease study of LEQEMBI.

ADUHELM (aducanumab)

• In March 2022 we announced new data showing that after nearly two and a half years of treatment (128 weeks) with ADUHELM injection 100 mg/mL for intravenous use, patients in the long-term extension phase of the Phase 3 trials continued to experience significant reductions in two key Alzheimer's disease pathologies, amyloid beta plaques and plasma p-tau181.

• In March 2022 The Journal of Prevention of Alzheimer's Disease published a peer-reviewed manuscript detailing data from the pivotal Phase 3 EMERGE and ENGAGE studies of ADUHELM 100 mg/mL injection for intravenous use in early Alzheimer's disease.

The publication includes results from the primary, secondary and tertiary endpoints in the trials, as well as safety data and biomarker sub-studies.

• In March 2022 we submitted the final study protocol for the confirmatory Phase 4 ENVISION study of ADUHELM to the FDA for review and approval.

• In April 2022 the Centers for Medicare and Medicaid Services (CMS) released a final NCD for the class of anti-amyloid treatments in Alzheimer's disease, including ADUHELM.

The final NCD confirmed coverage with evidence development, in which patients with Medicare can only access treatment if they are part of an approved clinical trial.

This decision effectively resulted in denying all Medicare beneficiaries access to ADUHELM.

• In April 2022 we announced our plans to offer a continuity of care plan for U.S.

patients currently treated with ADUHELM, as a result of the CMS decision.

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Neuropsychiatry

Zuranolone (BIIB125)

• In February 2022 we and Sage announced the Phase 3 CORAL study of zuranolone in people with MDD met the trial objectives, demonstrating a rapid and statistically significant reduction in depressive symptoms at Day 3 and over the 2-week treatment period, achieving the primary and key secondary endpoints.

• In June 2022 we and Sage announced that the Phase 3 SKYLARK study of zuranalone in women with PPD met its primary and all key secondary endpoints.

• In October 2022 we and Sage presented additional data from the Phase 3 SKYLARK study of zuranalone in women with PPD.

This data was presented at the European College of Neuropsychopharmacology (ECNP) Congress.

• In December 2022 we and Sage completed the rolling submission of a NDA to the FDA for the approval of zuranolone for the potential treatment of MDD and PPD.

This submission completes the NDA filing initiated earlier in 2022.

• In February 2023 the FDA accepted the NDA and granted Priority Review for zuranolone, with a PDUFA action date of August 5, 2023.

Neuromuscular Disorders

• In October 2023 Eisai presented new data for LEQEMBI 100 mg/mL injection for intravenous use at the 2023 CTAD conference.

The new data suggests that there is continued benefit associated with LEQEMBI treatment as patients continued to show benefits at 24 months of treatment and after the removal of amyloid plaques.

• In September 2023 we and Eisai announced that the LEQEMBI intravenous infusion (200 mg, 500 mg, lecanemab) was approved in Japan as a treatment for slowing progression of mild cognitive impairment and mild dementia due to Alzheimer's disease.

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• In July 2023 we and Eisai announced the results of a detailed analysis of the Phase 3 CLARITY Alzheimer's disease study of LEQEMBI at the 2023 AAIC conference.

The study provided further Phase 3 analysis showing benefits of LEQEMBI on both amyloid-beta and tau, two underlying pathological hallmarks of Alzheimer's disease, as well as new data on subcutaneous formulation showing promising PK/PD data modeling on efficacy and safety, representing a potential new option for administering therapy.

• In March 2023 we and Eisai announced that three additional detailed analyses from the Phase 2b clinical study (Study 201) of lecanemab, evaluating the efficacy and safety of lecanemab for mild cognitive impairment due to Alzheimer's disease and mild Alzheimer's disease, were published in peer-reviewed journals.

• In October 2023 we announced new Phase 1b clinical data from the Phase 1b clinical study of BIIB080, an investigational ASO therapy targeting tau, in mild Alzheimer's disease, showing favorable trends on multiple exploratory endpoints of cognition and activities of daily living in Alzheimer's disease.

• In October 2023 JAMA Neurology published biomarker data from the placebo-controlled period and long-term extension phase of the BIIB080 Phase 1b study of the ASO which targets tau pre-mRNA in early-stage Alzheimer's disease.

This publication includes preliminary data in 46 patients which showed that the investigational therapy substantially reduced soluble and aggregated pathologic tau in patients with mild Alzheimer's disease.

• In April 2023 Nature Medicine published a manuscript detailing promising results from Biogen's multiple ascending dose Phase 1b trial, which evaluated the safety, pharmacokinetics and target engagement of Biogen's BIIB080.

• In March 2023 we presented new data from the Phase 1b clinical study of BIIB080 at the 2023 International Conference on Alzheimer's and Parkinson's Diseases, showing that BIIB080 substantially reduced tau protein levels in patients with early-stage Alzheimer's disease.

SPINRAZA (nusinersen)

• In March 2022 we announced the first patient was treated in the global Phase 3b ASCEND study, which is designed to evaluate the clinical outcomes and assess the safety of a higher dose of SPINRAZA in children, teens and adults with later-onset SMA who were previously treated with Evrysdi.

• In October 2022 the first patient in the Phase 1 study of BIIB115, an investigational ASO in development for SMA, was dosed.

Tofersen (BIIB067)

• In June 2022 we announced new 12-month data for tofersen demonstrating that earlier initiation of tofersen compared to delayed initiation (six months later in the open-label extension study) slowed declines in clinical function, respiratory function, muscle strength and quality of life.

• In July 2022 the FDA accepted the NDA and granted Priority Review for tofersen, an investigational antisense drug being evaluated for people with superoxide dismutase 1 (SOD1) ALS, which currently has a PDUFA action date of April 25, 2023.

• In September 2022 The New England Journal of Medicine published detailed results from the Phase 3 VALOR study of tofersen, including the combined analysis of the Phase 3 VALOR study and its open-label extension study evaluating tofersen for the potential treatment of SOD1 ALS.

• In December 2022 the EMA accepted for review the MAA for tofersen.

Movement Disorders

BIIB122 (DNL151)

• In May 2022 dosing commenced in the Phase 2b LUMA study of BIIB122, a small molecule inhibitor of leucine-rich repeat kinase 2 (LRRK2), evaluating the efficacy and safety of BIIB122 compared to placebo in approximately 640 patients with early stage Parkinson's disease.

• In October 2022 we and our collaboration partner Denali Therapeutics Inc.

(Denali) announced the initiation of the Phase 3 LIGHTHOUSE study of BIIB122 in patients with Parkinson's disease and a confirmed pathogenic mutation in the LRRK2 gene.

• In June 2022 we entered into a collaboration and license agreement with Alectos Therapeutics Inc.

(Alectos) to develop and commercialize ALO1811, a novel preclinical selective GBA2 inhibitor, for the potential oral disease modifying treatment for patients with Parkinson's disease.

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Litifilimab (BIIB059)

• In July 2022 The New England Journal of Medicine published positive results from the cutaneous lupus erythematosus (CLE) portion of the two-part Phase 2 LILAC study (Part B) evaluating litifilimab, an investigational drug for the treatment of lupus.

The study met its primary endpoint by demonstrating the enhanced efficacy of litifilimab compared to placebo in reducing skin disease activity.

• In September 2022 The New England Journal of Medicine published a second manuscript detailing positive results from the systemic lupus erythematosus (SLE) portion of the two-part Phase 2 LILAC study (Part A) evaluating litifilimab.

The study met its primary endpoint by demonstrating that litifilimab was associated with a statistically significant reduction in total active joint count compared to placebo.

• In October 2022 the first patient was dosed in the Phase 2/3 AMETHYST study of litifilimab, evaluating the efficacy and safety of litifilimab compared to placebo in patients with CLE.

BIIB801 (referencing CIMZIA)

• In February 2022 we entered into a commercialization and license agreement with Xbrane Biopharma AB (Xbrane) to develop, manufacture and commercialize BIIB801, a proposed certolizumab pegol biosimilar referencing CIMZIA.

• In June 2023 we announced new data from the Phase 4 RESPOND study, which is designed to evaluate the clinical outcomes and safety following treatment with SPINRAZA in infants and toddlers with SMA who have unmet clinical needs after treatment with ZOLGENSMA (onasemnogene abeparvovec-xioi).

Interim results from the Phase 4 RESPOND study showed improved motor function in most participants treated with SPINRAZA after ZOLGENSMA.

SKYCLARYS (omaveloxolone)

• In February 2024 the EC approved SKYCLARYS in the E.U.

for the treatment of FA in adults and adolescents aged 16 years and older.

SKYCLARYS is the first treatment approved within the E.U.

for this rare, genetic, progressive neurodegenerative disease.

• In December 2023 the CHMP of the EMA issued a positive opinion recommending marketing authorization for omaveloxolone for the treatment of FA in people aged 16 years and older.

QALSODY (tofersen)

• In August 2023 the first Veteran was dosed with QALSODY following the VA's coverage for QALSODY.

• In July 2023 the European Academy of Neurology guideline recommendations on the management of ALS provided updated guidelines recommending that tofersen be offered as first-line treatment for patients with progressive ALS caused by pathogenic mutations in SOD1.

• In June 2023 the first patient with SOD1-ALS, outside of a clinical trial or early access program, was dosed with QALSODY.

• In April 2023 the FDA approved QALSODY for the treatment of ALS in adults who have a mutation in the SOD1 gene.

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BYOOVIZ (referencing LUCENTIS)

• In June 2022 we and Samsung Bioepis announced that BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, launched in the U.S.

BIIB800 (referencing ACTEMRA)

• In June 2022 we and our collaboration partner Bio-Thera Solutions, Ltd.

(Bio-Thera) presented positive results from the Phase 3 study of BIIB800, a proposed tocilizumab biosimilar referencing ACTEMRA, an anti-interleukin-6 receptor monoclonal antibody, for the treatment of severe, active and progressive rheumatoid arthritis.

The data was presented at the 2022 Annual European Congress of Rheumatology.

• In September 2022 the EMA accepted for review the MAA for BIIB800.

• In December 2022 the FDA accepted for review the abbreviated BLA for BIIB800.

Discontinued Programs

• In March 2022 we and Ionis Pharmaceuticals Inc.

(Ionis) announced that the Phase 1 study of BIIB078 in ALS did not meet any secondary efficacy endpoints and it did not demonstrate clinical benefit.

Based on these results, we discontinued development of BIIB078.

• In June 2022 we discontinued further development of BIIB100 for the potential treatment of certain neurological and neurodegenerative diseases, primarily in ALS, based on the decision by management as part of its strategic review process.

• In July 2022 we announced that the Phase 2 TALLY study of BIIB104 in cognitive impairment associated with schizophrenia did not meet its primary or secondary efficacy endpoints.

Given the consistent lack of efficacy observed across the primary and secondary measures of cognition and functioning, we decided to discontinue the BIIB104 program.

• In 2022 we discontinued further development of BIIB118 (CK1 inhibitor) for the potential treatment of patients with behavioral and neurological symptoms across various psychiatric and neurological diseases, based on the decision by management as part of its strategic review process.

• In December 2022 we discontinued further development of vixotrigine (BIIB074) for the potential treatment of trigeminal neuralgia (TGN) and diabetic painful neuropathy (DPN), based on regulatory, development and commercialization challenges.

• In February 2023 we terminated our license and collaboration agreement with InnoCare Pharma Limited (InnoCare) for orelabrutinib, an oral small molecule Bruton's tyrosine kinase inhibitor for the potential treatment of MS.

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• In October 2023 BYOOVIZ was granted an interchangeability designation by the FDA and was deemed interchangeable to Genentech's LUCENTIS.

• In March 2023 we announced that BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, launched in Canada.

• In February 2023 Samsung Bioepis announced that BYOOVIZ launched in Germany.

TOFIDENCE (referencing ACTEMRA)

• In September 2023 the FDA approved TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA, for the treatment of severe, active and progressive rheumatoid arthritis.

DISCONTINUED PROGRAMS AND STUDIES

ENVISION STUDY

In November 2023 we notified Neurimmune of our decision to terminate our collaboration and license agreement with Neurimmune, to discontinue the development and commercialization of ADUHELM and to terminate the ENVISION clinical study.

In connection with this termination, we recorded close-out costs of approximately $60.0 million in research and development expense within our consolidated statements of income for the year ended December 31, 2023.

In September 2023 we discontinued our EMBARK study for aducanumab.

In connection with this discontinuation we recorded termination costs of approximately $43.0 million in research and development expense within our consolidated statements of income for the year ended December 31, 2023 .

ACORDA COLLABORATION

In January 2024 we notified Acorda of our decision to terminate our collaboration and license agreement, effective January 1, 2025.

As a result of this termination, Acorda will regain global commercialization rights to FAMPYRA.

In June 2023 we and Denali announced plans to terminate the Phase 3 LIGHTHOUSE study for BIIB122, a small molecule inhibitor of LRRK2 in Parkinson's disease.

The protocol for the Phase 2b LUMA study for BIIB122 in patients with early-stage Parkinson’s disease was amended to now include eligible patients with a LRRK2 genetic mutation in addition to continuing to enroll eligible patients with early-stage idiopathic Parkinson’s disease.

In April 2023 we announced that we would terminate the development of BIIB093 (glibenclamide IV), currently in a Phase 3 study for LHI and a Phase 2 study for brain contusion, due to operational challenges and other strategic considerations.

In connection with this termination, we recorded close-out costs of approximately $13.2 million in research and development expense within our consolidated statements of income for the year ended December 31, 2023.

In April 2023 we announced that we will be pausing the initiation of a Phase 2b study for BIIB131 (TMS-007) for acute ischemic stroke and will continue to assess whether to initiate this study.

We sold the rights to BIIB131 to a third-party biopharmaceutical company in exchange for an upfront with potential milestones and future royalties on global sales.

In April 2023 we announced that we would discontinue further development of BIIB132 in spinocerebellar ataxia type 3, as part of our ongoing research and development prioritization initiative.

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MARKETED PRODUCTS

The following graph shows our revenue by product and revenue from anti-CD20 therapeutic programs for the years ended December 31, 2022, 2021 and 2020.

The following graph shows our product revenue and revenue from anti-CD20 therapeutic programs for the years ended December 31, 2023, 2022 and 2021.

(1) MS includes TECFIDERA, VUMERITY, AVONEX, PLEGRIDY, TYSABRI and FAMPYRA.

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during the fourth quarter of 2021.

(2) SMA includes SPINRAZA.

(3) Alzheimer's disease includes ADUHELM.

(2) Rare disease includes SPINRAZA, QALSODY, which became commercially available in the U.S.

during the second quarter of 2023, and SKYCLARYS, which was obtained as part of our acquisition of Reata in September 2023.

SKYCLARYS became commercially available in the U.S.

during the second quarter of 2023 and we began recognizing revenue from SKYCLARYS in the U.S.

during the fourth quarter of 2023, subsequent to our acquisition.

(3) Biosimilars includes BENEPALI, IMRALDI, FLIXABI and BYOOVIZ.

BYOOVIZ launched in the U.S.

in June 2022 and became commercially available during the third quarter of 2022.

(5) Anti-CD20 therapeutic programs include RITUXAN, RITUXAN HYCELA, GAZYVA and OCREVUS.

(6) Other includes FUMADERM.

BYOOVIZ became commercially available in the U.S.

during the third quarter of 2022 and commercially available in certain international markets in 2023.

(4) Anti-CD20 therapeutic programs include RITUXAN, RITUXAN HYCELA, GAZYVA, OCREVUS and LUNSUMIO.

LUNSUMIO became commercially available in the U.S.

during the first quarter of 2023.

(5) Other includes FUMADERM, ADUHELM and ZURZUVAE, which became commercially available in the U.S.

during the fourth quarter of 2023.

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Product sales for TECFIDERA, TYSABRI and SPINRAZA each accounted for more than 10.0% of our total revenue for the years ended December 31, 2023, 2022 and 2021.

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Risk Factors included in this report.

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MULTIPLE SCLEROSIS

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RMS in the U.S.

Relapsing-remitting MS (RRMS) in the E.U.

RRMS in the E.U.

RMS in the U.S.

RRMS in the E.U.

Alkermes Pharma Ireland Limited, a subsidiary of Alkermes plc (Alkermes) U.S.

Alkermes Pharma Ireland Limited, a subsidiary of Alkermes U.S.

RMS None U.S.

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Crohn's disease in the U.S.

Walking ability for patients with MS Acorda Therapeutics, Inc.

(Acorda) France

Walking ability for patients with MS Acorda France

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For additional information on our collaboration arrangements with Alkermes and Acorda, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

Neuromuscular Disorders

SMA is characterized by loss of motor neurons in the spinal cord and lower brain stem, resulting in severe and progressive muscular atrophy and weakness.

Ultimately, individuals with the most severe type of SMA can become paralyzed and have difficulty performing the basic functions of life, like breathing and swallowing.

Due to a deletion or mutations in the SMN1 gene, people with SMA do not produce enough survival motor neuron (SMN) protein, which is critical to the survival of the neurons that control muscles.

The severity of SMA correlates with the amount of SMN protein.

People with Type 1 SMA, the most severe life-threatening form, produce very little SMN protein and do not

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achieve the ability to sit without support, and typically do not live beyond two years of age without respiratory support and nutritional interventions.

People with Type 2 and Type 3 SMA produce greater amounts of SMN protein and have less severe, but still life-altering, forms of SMA.

Our SMA product and major markets are as follows:

Product Indication Collaborator Major Markets

SMA Ionis U.S.

For additional information on our collaboration arrangements with Ionis, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

ALZHEIMER'S DISEASE

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Alzheimer's disease Eisai U.S.

Alzheimer's disease None U.S.

In November 2023 we notified Neurimmune of our decision to terminate our collaboration and license agreement with Neurimmune and to discontinue the development and commercialization of ADUHELM.

For additional information on our collaboration arrangements with Eisai, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

For additional information on the discontinuation of ADUHELM, please read Note 20, Investments in Variable Interest Entities , to our consolidated financial statements included in this report.

NEUROPSYCHIATRY

Neuropsychiatry includes ZURZUVAE for PPD, which became commercially available in the U.S.

during the fourth quarter of 2023.

Depression is a debilitating illness that is one of the leading contributors to disability worldwide and the second leading cause of disability in the U.S.

PPD symptoms are estimated to affect approximately one in eight women who have given birth in the U.S.

According to the Centers for Disease Control and Prevention, mental health conditions are the leading cause of maternal mortality with PPD among the most common complications during and after pregnancy.

Product Indication Collaborator Major Markets

PPD in adults Sage U.S.

For additional information on our collaboration with Sage, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

Rare disease includes SPINRAZA for SMA, SKYCLARYS for FA, which was obtained as part of our acquisition of Reata in September 2023 and QALSODY for ALS, which became commercially available in the U.S.

during the second quarter of 2023.

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SMA is characterized by loss of motor neurons in the spinal cord and lower brain stem, resulting in severe and progressive muscular atrophy and weakness.

Ultimately, individuals with the most severe type of SMA can become paralyzed and have difficulty performing the basic functions of life, like breathing and swallowing.

Due to a deletion or mutations in the SMN1 gene, people with SMA do not produce enough SMN protein, which is critical to the survival of the neurons that control muscles.

The severity of SMA correlates with the amount of SMN protein.

People with Type 1 SMA, the most severe life-threatening form, produce very little SMN protein and do not achieve the ability to sit without support, and typically do not live beyond two years of age without respiratory support and nutritional interventions.

People with Type 2 and Type 3 SMA produce greater amounts of SMN protein and have less severe, but still life-altering, forms of SMA.

FA is an inherited, debilitating and degenerative neuromuscular disorder that is typically diagnosed during adolescence and can ultimately lead to premature death.

Patients with FA experience progressive loss of coordination, muscle weakness and fatigue, which commonly progresses to motor incapacitation, wheelchair reliance and eventually death.

Symptoms generally first occur in children, with patients requiring a wheelchair by their teens or early-20s and generally have a life expectancy of their mid-30s.

ALS is a rare, progressive and fatal neurodegenerative disease that results in the loss of motor neurons in the brain and the spinal cord that are responsible for controlling voluntary muscle movement.

People with ALS experience muscle weakness and atrophy, causing them to lose independence as they steadily lose the ability to move, speak, eat and eventually breathe.

Average life expectancy for people with ALS is three to five years from time of symptom onset.

Multiple genes have been implicated in ALS.

Genetic testing helps determine if a person's ALS is associated with a genetic mutation, even in individuals without a known family history of the disease.

SOD1-ALS is diagnosed in approximately two percent of all ALS cases.

Our Rare disease products and major markets are as follows:

Product Indication Collaborator Major Markets

SMA Ionis U.S.

ALS in adults with SOD1 gene Ionis U.S.

FA in adults and adolescents aged 16 years and older

For additional information on our collaboration arrangements with Ionis, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

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Biosimilars are a group of biologic medicines that are highly similar to currently available biologic therapies developed by companies known as "originators".

Under our agreements with Samsung Bioepis, we commercialize three anti-tumor necrosis factor (TNF) biosimilars in certain countries in Europe:

Under our agreements with Samsung Bioepis, we commercialize three anti-TNF biosimilars in certain countries in Europe:

BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE.

We have also secured the exclusive rights to commercialize BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, which was approved in the U.S., the E.U.

and the United Kingdom (U.K.) during the third quarter of 2021.

BYOOVIZ launched in the U.S.

in June 2022 and became commercially available during the third quarter of 2022.

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We have also secured the exclusive rights to commercialize BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, which is commercially available in the U.S.

and certain international markets, and TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA, which was approved by the FDA during the third quarter of 2023.

Our current biosimilar products and major markets are as follows:

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For additional information on our collaboration arrangements with Samsung Bioepis, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

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GENENTECH RELATIONSHIPS

We have agreements with Genentech that entitle us to certain business and financial rights with respect to RITUXAN, RITUXAN HYCELA, GAZYVA, OCREVUS, LUNSUMIO, which was granted accelerated approval in the U.S.

during the fourth quarter of 2022, glofitamab and options to add other potential anti-CD20 therapies.

We have agreements with Genentech that entitle us to certain business and financial rights with respect to RITUXAN, RITUXAN HYCELA, GAZYVA, OCREVUS, LUNSUMIO, COLUMVI, which was granted accelerated approval by the FDA during the second quarter of 2023, and have the option to add other potential anti-CD20 therapies.

Our current anti-CD20 therapeutic programs and major markets are as follows:

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Relapsed or refractory follicular lymphoma U.S.

Relapsed or refractory diffuse large B-cell lymphoma

Large B-cell lymphoma arising from follicular lymphoma U.S.

For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

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The insights gained from these engagements help us support patients with services, programs and applications that are designed to help patients lead better lives.

Among other things, we provide customer service and other related programs for our products, such as disease and product specific websites, insurance research services, financial assistance programs and the

facilitation of the procurement of our marketed products.

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We are dedicated to helping patients obtain access to our therapies.

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In the U.S., we have established programs that provide co-pay assistance or free product for qualified uninsured or underinsured patients, based on specific eligibility criteria.

We also provide charitable contributions to

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independent charitable organizations that assist patients with out-of-pocket expenses associated with their therapy.

We also provide charitable contributions to independent charitable organizations that assist patients with out-of-pocket expenses associated with their therapy.

We believe all healthcare stakeholders have a shared responsibility to ensure patients have equitable access to new, innovative medicines.

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We commercialize BENEPALI, IMRALDI and FLIXABI pursuant to our agreement with Samsung Bioepis in certain countries in Europe, as well as BYOOVIZ in the U.S.

We focus our sales and marketing efforts on specialist physicians in private practice or at major medical centers.

and certain international markets.

We focus our sales and marketing efforts on physicians in private practice or at major medical centers.

We use customary industry practices to market our products and to educate physicians.

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principally through wholesale and specialty distributors of pharmaceutical products and specialty pharmacies, mail order specialty distributors or shipping service providers.

In other countries, the distribution of our

products varies from country to country, including through wholesale distributors of pharmaceutical products and third-party distribution partners who are responsible for most marketing and distribution activities.

Eisai distributes AVONEX, TYSABRI, TECFIDERA and PLEGRIDY in India and other Asia-Pacific markets, excluding China.

In other countries, the distribution of our products varies from country to country, including through wholesale distributors of pharmaceutical products and third-party distribution partners who are responsible for most marketing and distribution activities.

RITUXAN, RITUXAN HYCELA, GAZYVA, OCREVUS and LUNSUMIO are distributed by the Roche Group and its sublicensees.

We distribute BENEPALI, IMRALDI and FLIXABI in certain countries in Europe and have an option to acquire exclusive rights to distribute these products in China, as well as BYOOVIZ in the U.S.

and certain international markets.

Our product sales to two wholesale distributors each accounted for more than 10.0% of our total revenue for the years ended December 31, 2023, 2022 and 2021, and on a combined basis, accounted for approximately 36.9%, 37.9% and 38.9%, respectively, of our gross product revenue.

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In addition, we license rights to various patents and patent applications.

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patents, as well as most foreign patents, are generally effective for 20 years from the date the earliest application was filed;

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patents on applications filed before June 8, 1995, may be effective until 17 years from the issue date, if that is later than the 20-year date.

In some cases, the patent term may be extended to recapture a portion of the term lost during regulatory review of the claimed therapeutic or, in the case of the U.S., because of U.S.

Patent and Trademark Office (USPTO) delays in prosecuting the application.

Specifically, in the U.S., under the Drug Price Competition and Patent Term Restoration Act of 1984, commonly known as the Hatch-Waxman Act, a patent that covers a drug approved by the FDA may be eligible for patent term extension (for up to 5 years, but not beyond a total of 14 years from the date of product approval) as compensation for patent term lost during the FDA regulatory review process.

The duration and extension of the term of foreign patents varies, in accordance with local law.

For example, supplementary protection certificates (SPCs) on some of our products have

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been granted in a number of European countries, compensating in part for delays in obtaining marketing approval.

Regulatory exclusivity, which may consist of regulatory data protection and market protection, also can provide meaningful protection for our products.

In some cases, the patent term may be extended to recapture a portion of the term lost during regulatory review of the claimed therapeutic or, in the case of the U.S., additional patent term may be awarded due to U.S.

Patent and Trademark Office delays in prosecuting the application.

In the U.S., under the Drug Price Competition and Patent Term Restoration Act of 1984, commonly known as the Hatch-Waxman Act, a patent that covers a drug approved by the FDA may be eligible for patent term extension (for up to 5 years, but not beyond a total of 14 years from the date of product approval) as compensation for patent term lost during the FDA regulatory review process.

The duration and extension of the term of foreign patents vary, in accordance with local law.

For example, in a number of European countries, SPCs can be granted to a product to compensate in part for delays in obtaining marketing approval.

Regulatory exclusivity, which may consist of regulatory data protection and market protection, can also provide meaningful protection for our products.

Regulatory data protection provides to the holder of a drug or biologic marketing authorization, for a set period of time, the exclusive use of the proprietary pre-clinical and clinical data that it created at significant cost and submitted to the applicable regulatory authority to obtain approval of its product.

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Market protection provides the holder of a drug or biologic marketing authorization the exclusive right to commercialize its product for a period of time, thereby preventing the commercialization of another product containing the same active ingredient(s) during that period.

Although the World Trade Organization's agreement on trade-related aspects of intellectual property rights (TRIPS) requires signatory countries to provide regulatory exclusivity to innovative pharmaceutical products, implementation and enforcement varies widely from country to country.

Although the World Trade Organization's agreement on trade-related aspects of intellectual property rights requires signatory countries to provide regulatory exclusivity to innovative pharmaceutical products, implementation and enforcement varies widely from country to country.

We also rely upon other forms of unpatented confidential information to remain competitive.

We protect such information principally through refraining from public disclosure and confidentiality agreements with our employees, consultants, outside scientific collaborators, scientists whose research we sponsor and other advisers.

We protect such information principally through refraining from public disclosure and utilizing confidentiality agreements with our employees, consultants, outside scientific collaborators, scientists whose research we sponsor and other advisers.

In the case of our employees, these agreements also provide, in compliance with relevant law, that inventions and other intellectual property conceived by such employees during their employment are our exclusive property.

Our trademarks are important to us and are generally covered by trademark applications or registrations in the USPTO and the patent or trademark offices of other countries.

We also use trademarks licensed from third parties, such as the trademark FAMPYRA, which we license from Acorda.

Our trademarks are important to us and are generally covered by trademark applications or registrations in the U.S.

Patent and Trademark Office and the patent or trademark offices of other countries.

We also use trademarks licensed from third parties.

Trademark protection varies in accordance with local law, and continues in some countries as long as the trademark is used and in other countries as long as the trademark is registered.

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and Europe that we currently consider of primary importance to our marketed products, including the territory, patent number, general subject matter and expected expiration dates.

Except as otherwise noted, the expected expiration dates

include any granted patent term extensions and issued SPCs.

In some instances, there are additional later-expiring patents relating to our products directed to, among other things, particular forms or compositions, methods of manufacturing or use of the drug in the treatment of particular diseases or conditions.

Except as otherwise noted, the expected expiration dates include any granted patent term extensions and issued SPCs.

In some instances, there may be additional later-expiring patents relating to our products directed to, among other things, particular forms or compositions, methods of manufacturing or use of the drug in the treatment of particular diseases or conditions.

We also continue to pursue additional patents and patent term extensions in the U.S.

and other territories covering various aspects of our products that may, if issued, extend exclusivity beyond the expiration of the patents listed in the table.

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Product Territory Patent No.

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PLEGRIDY U.S.

8,524,660 Methods of treatment 2023

8,017,733 Polymer conjugates of interferon beta-1a 2027

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11,292,845 Methods of treatment 2027

Europe 1,485,127 Methods of use 2023 (2)

Europe 2,170,390 Formulation 2028

Europe 2,236,154 Formulation 2024

Europe 2,676,967 Methods of use 2027

Europe 3,339,865 Safety-related assay 2031

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SPINRAZA U.S.

7,101,993 Oligonucleotides containing 2’-O-modified purines 2023

7,838,657 SMA treatment via targeting of SMN2 splice site inhibitory sequences 2027

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9,926,559 Compositions and methods for modulation of SMN2 splicing 2034

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10,266,822 SMA treatment via targeting of SMN2 splice site inhibitory sequences 2025

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Europe 3,449,926 Compositions and methods for modulation of SMN2 splicing 2030 (10)

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Product Territory Patent No.

General Subject Matter Patent

Expiration (1)

8,906,367 Method of providing disease-specific binding molecules and targets 2032 (11)

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8,025,878 Protofibril selective antibodies and the use thereof 2027 (1)(11)

10,385,341 Compositions for modulating SOD-1 expression 2035 (11)

10,669,546 Compositions for modulating SOD-1 expression 2035

10,968,453 Compositions for modulating SOD-1 expression 2035

ZURZUVAE U.S.

9,512,165 19-nor C3, 3-disubstituted C21-N-pyrazolyl steroids and methods of use thereof 2034 (9)

10,172,871 19-nor C3, 3-disubstituted C21-N-pyrazolyl steroids and methods of use thereof 2034 (9)

10,342,810 19-nor C3, 3-disubstituted C21-N-pyrazolyl steroids and methods of use thereof 2034 (9)

11,236,121 Crystalline 19-nor C3, 3-disubstituted C21-N-pyrazolyl steroid

SKYCLARYS U.S.

8,124,799 Antioxidant Inflammation Modulators:

Oleanolic Acid Derivatives with Amino and other Modifications at C-17 (Composition) 2029 (9)

8,440,854 Antioxidant Inflammation Modulators:

Oleanolic Acid Derivatives with Amino and other Modifications at C-17 (Composition) 2029 (9)

8,993,640 2,2-Difluoropropionamide Derivatives of Bardoxolone Methyl, Polymorphic Forms and Methods of Use Thereof (Composition) 2033 (9)

9,670,147 Antioxidant Inflammation Modulators:

Oleanolic Acid Derivatives with Amino and other Modifications at C-17 (Composition) 2029 (9)

9,701,709 2,2-Difluoropropionamide Derivatives of Bardoxolone Methyl, Polymorphic Forms and Methods of Use Thereof (Composition) 2033 (9)

11,091,430 Antioxidant Inflammation Modulators:

Oleanolic Acid Derivatives with Amino and other Modifications at C-17 (Treatment Method) 2029 (9)

Footnotes follow on next page.

Table of Conten ts

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(1) I n addition to patent protection, certain of our products are entitled to regulatory exclusivity in the U.S.

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TECFIDERA E.U.

Subject to appeal

PLEGRIDY U.S.

SPINRAZA U.S.

(2) For additional information as to the validity of this patent, please read Note 21, Litigation , to our consolidated financial statements included in this report.

SPINRAZA E.U.

ZURZUVAE U.S.

SKYCLARYS U.S.

(2) This patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2024.

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(9) A patent with this subject matter may be entitled to patent term extension in the U.S.

(10) This patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2032.

The existence of patents does not guarantee our right to practice the patented technology or commercialize the patented product.

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Risk Factors included in this report, and the discussion of legal proceedings related to certain patents described above is set forth in Note 21, Litigation, to our consolidated financial statements included in this report.

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Competition in the biopharmaceutical industry and the markets in which we operate is intense.

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Some of our competitors may have substantially greater financial, marketing, research and development and other resources than we do.

We believe that competition and leadership in the industry is based on managerial and technological excellence and innovation as well as establishing patent and other proprietary positions through research and development.

We believe that competition and leadership in the industry is based on scientific, managerial and technological excellence and innovation as well as establishing patent and other proprietary positions through research and development.

The achievement of a leadership position also depends largely upon our ability to maximize the approval, acceptance and use of our product candidates and the availability of adequate financial resources to fund facilities, equipment, personnel, clinical testing, manufacturing and marketing.

Another key aspect of remaining competitive in the industry is recruiting and retaining leading scientists and technicians to conduct our research activities and advance our development programs, including with the commercial expertise to effectively market our products.

Another key aspect of remaining competitive in the industry is recruiting and retaining leading scientists and technicians to conduct our research activities and advance our development programs, including with the regulatory and commercial expertise to effectively advance and market our products.

Competition among products approved for sale may be based, among other things, on patent position, product efficacy, safety, patient convenience, delivery devices, reliability, availability, reimbursement and price.

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In addition, the commercialization of certain of our own approved products, products of our collaborators and pipeline product candidates may negatively impact future sales of our existing products.

Our products and revenue streams continue to face increasing competition in many markets from the introduction of generic versions, prodrugs and biosimilars of existing products and products approved under abbreviated regulatory pathways.

Such products are likely to be sold at substantially lower prices than branded products.

Accordingly, the introduction of such products as well as other lower-priced competing products may significantly reduce both the price that we are able to charge for our products and the volume of products we sell, which will negatively impact our revenue.

In addition, in some markets, when a generic or biosimilar version of one of our products is commercialized, it may be automatically substituted for our product and significantly reduce our revenue in a short period of time.

We believe our long-term competitive position depends upon our success in discovering and developing innovative, cost-effective products that serve unmet medical needs, along with our ability to manufacture products efficiently and to launch and market them effectively in a highly competitive environment.

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MULTIPLE SCLEROSIS

TECFIDERA, AVONEX, PLEGRIDY, TYSABRI and VUMERITY each compete with one or more of the following branded products as well as generic and biosimilar versions of these products:

Our MS products and revenue streams continue to face increasing competition in many markets from the introduction of generic versions, prodrugs and biosimilars of existing products and products approved under abbreviated regulatory pathways.

Such products are likely to be sold at substantially lower prices than branded products.

In some jurisdictions a decrease in reimbursed price is mandated by law.

Competition in the MS market is intense.

Along with us, a number of companies are working to develop additional treatments for MS that may in the future compete with our MS products.

One such product that was approved in the U.S.

in 2017 and in the E.U.

in 2018 is OCREVUS, a treatment for RMS and PPMS that was developed by Genentech.

While we have a financial interest in OCREVUS, future sales of our MS products may be adversely affected if OCREVUS continues to gain market share, or if other MS products that we or our competitors are developing are commercialized.

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TECFIDERA, AVONEX, PLEGRIDY, TYSABRI and VUMERITY each compete with one or more of the following branded products as well as generic and biosimilar versions of some of these products:

Competing Product Competitor

AUBAGIO (teriflunomide) Sanofi Genzyme

BAFIERTAM (monomethyl fumarate) Banner Life Sciences

BETASERON/BETAFERON (interferon-beta-1b) Bayer Group

BRIUMVI (ublituximab-xiiy) TG Therapeutics, Inc.

(glatiramer acetate) Teva Pharmaceuticals Industries Ltd.

(interferon-beta-1b) Novartis AG

COPAXONE (glatiramer acetate) Teva Pharmaceuticals Industries Ltd.

EXTAVIA (interferon-beta-1b) Novartis AG

GILENYA (fingolimod) Novartis AG

GLATOPA (glatiramer acetate) Sandoz, a division of Novartis AG

KESIMPTA (ofatumumab) Novartis AG

LEMTRADA (alemtuzumab) Sanofi Genzyme

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PONVORY (ponesimod) Janssen Pharmaceutical Companies of Johnson & Johnson

(interferon-beta-1) EMD Serono

ZEPOSIA (ozanimod) BMS

BAFIERTAM (monomethyl fumarate) Banner Life Sciences

KESIMPTA (ofatumumab) Novartis AG

REBIF (interferon-beta-1) EMD Serono

TYRUKO (natalizumab-sztn) Sandoz, a division of Novartis AG

ZEPOSIA (ozanimod) Bristol Myers Squibb Company

Multiple TECFIDERA generic entrants are now in North America, Brazil and certain E.U.

countries and have deeply discounted prices compared to

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countries and have deeply discounted prices compared to TECFIDERA.

Following a favorable March 2023 decision of the CJEU affirming TECFIDERA's right to regulatory data and marketing protection and the EC determination in May 2023 that TECFIDERA is entitled to an additional year of market protection for its pediatric indication, we believe that TECFIDERA is entitled to regulatory marketing protection in the E.U.

until at least February 2, 2025, and are seeking to enforce this protection.

In December 2023, the EC revoked all centralized marketing authorizations for generic versions of TECFIDERA.

As of December 31, 2023, some of the TECFIDERA generics have not yet fully exited some E.U.

markets and we expect removal of all generics from the market will take additional time.

We are closely monitoring this situation and working to enforce our legal right to market protection.

In addition, we will continue to enforce our EP 2 653 873 patent related to TECFIDERA, which expires in 2028.

The generic competition for TECFIDERA has significantly reduced our TECFIDERA revenue and we expect that TECFIDERA revenue will continue to decline in the future.

In the E.U., we are seeking to enforce a patent granted in June 2022 that relates to TECFIDERA and expires in 2028.

In addition, we are litigating to affirm that TECFIDERA is entitled to regulatory data and market protection until at least February 2024.

Our Company, the EMA and the EC have each appealed the May 2021 decision of the European General Court, which annulled the EMA's decision not to validate an application for approval of a TECFIDERA generic on the basis that the EMA and EC conducted the wrong assessment when determining TECFIDERA's entitlement to regulatory data and marketing protection.

Our Company, the EMA and the EC have each appealed the General Court’s decision as wrongly decided and the appeal is pending.

On October 6, 2022, the Advocate General of the CJEU issued a nonbinding advisory opinion in Biogen's favor.

This opinion recommends that the CJEU set aside the judgment of the European General Court.

We are awaiting the decision of the CJEU.

FAMPYRA is indicated as a treatment to improve walking in adult patients with MS who have a walking disability and is the first treatment that addresses this unmet medical need with demonstrated efficacy in people with all types of MS.

FAMPYRA is currently the only therapy approved to improve walking in patients with MS.

Competition in the MS market is intense.

Along with us, a number of companies are working to develop additional treatments for MS that may in the future compete with our MS products.

One such product that was approved in the U.S.

in 2017 and in the E.U.

in 2018 is OCREVUS, a treatment for RMS and PPMS that was developed by Genentech.

We are also aware of a biosimilar entrant of TYSABRI that was approved in the U.S.

in August 2023 and the E.U.

in September 2023.

We believe that future sales of TYSABRI may be adversely affected by the entrance of this biosimilar.

For additional information on the U.S.

patent litigation related to a TYSABRI biosimilar, please read Note 21, Litigation , to our consolidated financial statements included in this report.

ALZHEIMER'S DISEASE

The market for the treatment of Alzheimer's disease is undeveloped and could be subject to rapid change in the future.

Most current treatments are symptomatic or intended to improve quality of life.

Along with us, several companies are working to develop additional treatments.

Most recently, we codeveloped LEQEMBI, a treatment to address a defining pathology of Alzheimer's disease and we and our collaborator Eisai are in the process of launching this product.

We are aware of other products now in development that, if approved, may also compete with LEQEMBI.

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SPINAL MUSCULAR ATROPHY

We face competition from a gene therapy product and an oral product.

We face competition from a gene therapy product ZOLGENSMA (onasemnogene abeparvovec-xioi) and an oral product EVRYSDI (risdiplam).

We expect that we will experience competition from both products in additional jurisdictions in the future, which may adversely affect our sales of SPINRAZA.

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Future sales of SPINRAZA may be adversely affected by the commercialization of competing products.

FUMADERM competes with several different types of therapies in the psoriasis market within Germany, including oral systemics such as methotrexate and cyclosporine.

FRIEDREICH'S ATAXIA

SKYCLARYS is the first treatment on the market for this indication and could face future competition from pipeline programs under development.

BENEPALI, IMRALDI and FLIXABI, the three biosimilar products we currently commercialize in certain countries in Europe pursuant to an agreement with Samsung Bioepis, compete with their reference products, ENBREL, HUMIRA and REMICADE, respectively, as well as other biosimilars of those reference products.

In addition, BYOOVIZ, a biosimilar product we currently commercialize in the U.S.

pursuant to an agreement with Samsung Bioepis, competes with its reference product LUCENTIS, as well as other biosimilars of this reference product.

BYOOVIZ, a biosimilar product we currently commercialize in the U.S.

and certain international markets pursuant to an agreement with Samsung Bioepis, competes with its reference product LUCENTIS, as well as other biosimilars of this reference product.

GENENTECH RELATIONSHIPS IN OTHER INDICATIONS

RITUXAN, RITUXAN HYCELA and GAZYVA in Oncology

RITUXAN, RITUXAN HYCELA and GAZYVA compete with a number of therapies in the oncology market, including TREANDA (bendamustine HCL), ARZERRA (ofatumumab), IMBRUVICA (ibrutinib) and ZYDELIG (idelalisib).

We also expect that over time RITUXAN HYCELA and GAZYVA will increasingly compete with RITUXAN in the oncology market.

In addition, we are aware of several other anti-CD20 molecules, including biosimilar products, that have been approved and are competing with RITUXAN, RITUXAN HYCELA and GAZYVA in the oncology and other markets.

RITUXAN, RITUXAN HYCELA, GAZYVA and LUNSUMIO in Oncology

RITUXAN, RITUXAN HYCELA, GAZYVA and LUNSUMIO compete with a number of therapies in the oncology market, including TREANDA (bendamustine HCL), ARZERRA (ofatumumab), IMBRUVICA (ibrutinib) and ZYDELIG (idelalisib) and other new innovative oncological therapies.

B i osimilar products referencing RITUXAN have launched in the U.S and are being offered at lower prices.

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RITUXAN in Rheumatoid Arthritis

RITUXAN competes with several different types of therapies in the rheumatoid arthritis market, including, among others, traditional disease-modifying anti-rheumatic drugs such as steroids, methotrexate and cyclosporine, TNF inhibitors, ORENCIA (abatacept), ACTEMRA (tocilizumab) and XELJANZ (tofacitinib).

We are also aware of other products, including biosimilars, in development that, if approved, may

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compete with RITUXAN in the rheumatoid arthritis market.

We are also aware of other products, including biosimilars, in development that, if approved, may compete with RITUXAN in the rheumatoid arthritis market.

RESEARCH AND DEVELOPMENT PROGRAMS

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Our research efforts are focused on better understanding the underlying biology of diseases so we can discover and deliver treatments that have the potential to make a real difference in the lives of patients with high unmet medical needs.

By applying our expertise in biologics and our growing capabilities in small molecule, antisense, gene therapy, gene editing and other technologies, we target specific medical needs where we believe new or better treatments are needed.

We intend to continue committing significant resources to targeted research and development

opportunities where there is a significant unmet need and where a drug candidate has the potential to be highly differentiated.

By applying our expertise in biologics and our capabilities in small molecule, antisense, gene therapy and other technologies, we target specific medical needs where we believe new or better treatments are needed.

We intend to continue committing significant resources to targeted research and development opportunities where there is a significant unmet need and where a drug candidate has the potential to be highly differentiated.

As part of our ongoing research and development efforts, we have devoted significant resources to conducting clinical studies to advance the development of new pharmaceutical products and technologies and to explore the utility of our existing products in treating disorders beyond those currently approved in their labels.

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For additional information on our research and development expense included in our consolidated statements of income, please read Item 7.

Management's Discussion and Analysis of Financial Condition and Results of Operations included in this report.

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The table below highlights our current research and development programs that are in clinical trials and the current phase of such programs.

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Alzheimer's Disease and

Dementia Lecanemab (Aβ mAb)*** - Alzheimer's Filed in the U.S., E.U.

Lecanemab (Aβ mAb)* - Preclinical Alzheimer's Phase 3

Aducanumab (Aβ mAb)** - Alzheimer's Filed in Japan and Other Markets

BIIB080 (tau ASO)* - Alzheimer's Phase 2

Dementia Lecanemab (Aβ mAb) (1)(2) - Alzheimer's

Filed in the E.U.

and Other Markets

Lecanemab (Aβ mAb) (1) - Preclinical Alzheimer's

BIIB080 (tau ASO) (1) - Alzheimer's

BIIB113 (OGA inhibitor) - Alzheimer's Phase 1

Neuropsychiatry Zuranolone (GABA A PAM) (1)(4) - MDD

Filed in the U.S.

Zuranolone (GABA A PAM) (1) - PPD

Filed in the U.S.

Specialized Immunology Dapirolizumab pegol (anti-CD40L)* - SLE Phase 3

Approved in the U.S.

Specialized Immunology Dapirolizumab pegol (anti-CD40L) (1) - SLE

Litifilimab (anti-BDCA2) - SLE Phase 3

Litifilimab (anti-BDCA2) - CLE Phase 2/3

Neuromuscular Disorders Tofersen (SOD1 ASO)* - SOD1 ALS Filed in the U.S.

Neuromuscular Disorders Omaveloxolone (Nrf2 activator) - FA Approved in the U.S.

Tofersen (SOD1 ASO) (1)(3) - SOD1 ALS

Approved in the U.S.;

Filed in the E.U.

BIIB105 (ataxin-2 ASO) # - ALS

BIIB115 (SMN ASO)* - SMA Phase 1

Parkinson's Disease and

Movement Disorders BIIB122 (DNL151) * - LRRK2 Parkinson's

BIIB122 (DNL151) * - Parkinson's

BIIB124 (SAGE-324)* - Essential Tremor Phase 2

BIIB094 (ION859) # - Parkinson's

BIIB101 (ION464) # - Multiple System Atrophy

BIIB132 (ATXN-3 ASO) # - SCA3

BIIB115 (SMN ASO) (1) - SMA

Parkinson's and

Movement Disorders BIIB122 (LRRK2 inhibitor) (1) - Parkinson's

BIIB124 (GABA A PAM) (1) - Essential Tremor

BIIB094 (LRRK2 ASO) # - Parkinson's

BIIB101 (a-syn ASO) # - Multiple System Atrophy

Multiple Sclerosis BIIB091 (peripheral BTK inhibitor) - MS Phase 2

BIIB107 (anti-VLA4) - MS Phase 1

Neurovascular Glibenclamide IV (SUR1-TRPM4 Inhibitor) - LHI^ Stroke Phase 3

Glibenclamide IV (SUR1-TRPM4 Inhibitor) - Brain Contusion Phase 2

BIIB131 (TMS-007) - Acute Ischemic Stroke Phase 2

Genetic Neurodevelopmental Disorders BIIB121 (UBE3A ASO) # - Angelman Syndrome

Neuropathic Pain Cemdomespib (Hsp90 modulator) - DPNP Phase 2

(1) Collaboration program

(2) Granted accelerated approval in the U.S.

in June 2021 under the brand name ADUHELM.

in January 2023 and traditional approval in the U.S.

in July 2023, Japan in September 2023 and China in January 2024 under the brand name LEQEMBI.

(3) Granted accelerated approval in the U.S.

in January 2023 under the brand name LEQEMBI and filed for traditional approval in the U.S., E.U.

in April 2023 under the brand name QALSODY.

(4) In August 2023 the FDA issued a CRL for the NDA for zuranolone in the treatment of adults with MDD.

We and Sage are continuing to seek feedback from the FDA and evaluating next steps.

# Option agreement

^ Large Hemispheric Infarction (LHI)

For information about certain of our agreements with collaborators and other third parties, please read the subsection entitled Business Relationships below and Note 2, Acquisitions , Note 19, Collaborative and Other Relationships, and Note 20, Investments in Variable Interest Entities, to our consolidated financial statements included in this report.

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BUSINESS RELATIONSHIPS

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For additional information on certain of these relationships, including their ongoing financial and accounting impact on our business, please read Note 19, Collaborative and Other Relationships , to our consolidated financial statements included in this report.

Eisai Co., Ltd.

We have a collaboration agreement with Eisai to jointly develop and commercialize LEQEMBI (lecanemab), an anti-amyloid antibody for the treatment of Alzheimer's disease.

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All costs, including research, development, sales and marketing expense, are shared equally between us and Eisai.

Upon LEQEMBI marketing approval, we and Eisai will co-promote LEQEMBI and share profits and losses equally.

We and Eisai co-promote LEQEMBI and share profits and losses equally.

We currently manufacture LEQEMBI drug substance and drug product and in March 2022 we extended our supply agreement with Eisai related to LEQEMBI from five years to ten years for the manufacture of LEQEMBI drug substance.

We also have a collaboration agreement with Eisai for ADUHELM.

Under our initial ADUHELM Collaboration Agreement, we would lead the ongoing development of ADUHELM, and we and Eisai would co-promote ADUHELM with a region-based profit split.

On March 14, 2022, we amended our ADUHELM Collaboration Agreement with Eisai.

Eisai's share of development, commercialization and manufacturing expense was limited to $335.0 million for the period from January

1, 2022 to December 31, 2022, which was achieved as of December 31, 2022.

Once this limit was achieved, we became responsible for all ADUHELM related costs.

In addition, we and Eisai co-promote AVONEX, TYSABRI and TECFIDERA in Japan in certain settings and Eisai distributes AVONEX, TYSABRI, TECFIDERA and PLEGRIDY in India and other Asia-Pacific markets, excluding China.

SAGE THERAPEUTICS, INC .

We have a global collaboration and license agreement with Sage to jointly develop and commercialize zuranolone for the potential treatment of MDD and PPD and BIIB124 (SAGE-324) for the potential treatment of essential tremor with potential in other neurological conditions such as epilepsy.

We have a global collaboration and license agreement with Sage to jointly develop and commercialize ZURZUVAE (zuranolone) for the treatment of PPD and potential treatment of MDD and BIIB124 (SAGE-324) for the potential treatment of essential tremor with potential in other neurological conditions such as epilepsy.

Under this collaboration, both companies will share equal responsibility and costs for development as well as profits and losses for commercialization in the U.S.

Outside the U.S., we are responsible for development and commercialization, excluding Japan, Taiwan and South Korea, with respect to zuranolone and may pay Sage potential tiered royalties in the high teens to low twenties.

Ionis Pharmaceuticals, Inc .

Outside of the U.S., we are responsible for development and commercialization, excluding Japan, Taiwan and South Korea, with respect to zuranolone and may pay Sage potential tiered royalties in the high teens to low twenties.

We have an exclusive, worldwide option and collaboration agreement with Ionis relating to the development and commercialization of antisense therapeutics for up to three gene targets.

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In addition, we have research collaboration agreements with Ionis under which both companies perform discovery level research and will develop and commercialize new ASO drug candidates for the potential treatment of SMA and additional antisense or other therapeutics for the potential treatment of neurological diseases.

Genentech, Inc.

(Roche Group)

during the fourth quarter of 2022, glofitamab and options to add other potential anti-CD20 therapies.

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Denali Therapeutics Inc.

In December 2018 we exercised our option with Ionis and obtained a worldwide, exclusive, royalty-bearing license to develop and commercialize QALSODY (tofersen), for the treatment of ALS with SOD1 mutations.

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We have a collaboration and license agreement with Denali to co-develop and co-commercialize Denali's small molecule inhibitors of LRRK2 for Parkinson's disease.

Under this collaboration, both companies share responsibility and costs for global development based on specified percentages as well as profits and losses for commercialization in the U.S.

Under the LRRK2 Collaboration, both companies share responsibility and costs for global development based on specified percentages as well as profits and losses for commercialization in the U.S.

Outside the U.S.

and China we are responsible for commercialization and may pay Denali potential tiered royalties.

In addition to the LRRK2 program, we also have an exclusive option to license two preclinical programs from Denali’s Transport Vehicle platform, including its Antibody Transport Vehicle (ATV):

ATV enabled anti-amyloid beta program and a second program utilizing its Transport Vehicle technology.

Further, we have the right of first negotiation on two additional ATV-enabled therapeutics for indications within specific neurodegenerative diseases, should Denali decide to seek a collaboration for such programs.

Samsung Bioepis Co., Ltd.

In February 2012 we entered into a joint venture agreement with Samsung BioLogics establishing an entity, Samsung Bioepis, to develop, manufacture and market biosimilar products.

We also have an agreement with Samsung Bioepis to commercialize, over a 10-year term, three anti-TNF biosimilar product candidates in certain countries in Europe and, in the case of BENEPALI, Japan.

SAMSUNG BIOEPIS

We have an agreement with Samsung Bioepis to commercialize, over a 10-year term, three anti-TNF biosimilar product candidates in certain countries in Europe and, in the case of BENEPALI, Japan.

Under this agreement, we are commercializing BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE, in certain countries in Europe.

In December 2019 we completed a transaction with Samsung Bioepis and acquired an option to extend our existing commercial agreement with Samsung Bioepis for BENEPALI, IMRALDI and FLIXABI in certain countries in Europe.

We have also secured the exclusive rights to commercialize BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, which was approved in the U.S., the E.U.

We have also secured the exclusive rights to commercialize BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, which has been approved in the U.S.

and certain international markets, and TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA, which was approved in the U.S.

during the third quarter of 2023.

BYOOVIZ launched in the U.S.

in June 2022 and became commercially available during the third quarter of 2022.

In addition to our commercialization agreements with Samsung Bioepis, we license certain of our proprietary technology to Samsung Bioepis in connection with Samsung Bioepis' development, manufacture and commercialization of its biosimilar products.

In April 2022 we completed the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics.

Under the terms of this transaction, we received approximately $1.0 billion in cash at closing and expect to receive approximately

$1.3 billion in cash to be deferred over two payments of approximately $812.5 million due at the first anniversary and approximately $437.5 million due at the second anniversary of the closing of this transaction.

As part of this transaction, we are also eligible to receive up to an additional $50.0 million upon the achievement of certain commercial milestones.

Our policy for contingent payments of this nature is to recognize the payments in the period that they become realizable, which is generally the same period in which the payments are earned.

For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 3, Dispositions, to our consolidated financial statements included in this report.

We have a collaboration agreement with UCB to jointly develop and commercialize dapirolizumab pegol, an anti-CD40L pegylated Fab, for the potential treatment of SLE and other future agreed indications.

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If marketing approval is obtained, both companies will co-promote dapirolizumab pegol and share profits and losses equally.

Sangamo Therapeutics, Inc.

We have a collaboration and license agreement with Sangamo Therapeutics, Inc.

(Sangamo) to develop and commercialize ST-501 for tauopathies, including Alzheimer’s disease;

ST-502 for synucleinopathies, including Parkinson’s disease;

a third neuromuscular disease target;

and up to nine additional neurological disease targets to be identified and selected within a five-year period.

The companies are leveraging Sangamo's proprietary zinc finger protein technology delivered via adeno-associated virus to modulate the expression of key genes involved in neurological diseases.

Under this collaboration, we may pay Sangamo tiered royalties on potential net sales of any products developed under this collaboration in the high single digit to sub-teen percentages.

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Our current and contemplated activities and the products, technologies and processes that result from such activities are subject to substantial government regulation.

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The FDA has substantial discretion in the product approval process, and it is impossible to predict with any certainty whether and when the FDA will grant marketing approval.

The agency may require the sponsor of a BLA or NDA to conduct additional clinical studies or to provide other scientific or technical information about the product, and these additional requirements may lead to unanticipated delays or expenses.

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unanticipated delays or expenses.

Furthermore, even if a product is approved, the approval may be subject to limitations based on the FDA's interpretation of the existing pre-clinical and/or clinical data.

The FDA has developed four distinct approaches intended to facilitate the development and expedite the regulatory review of therapeutically important drugs, especially when the drugs are the first

available treatment or have advantages over existing treatments:

The FDA has developed four distinct approaches intended to facilitate the development and expedite the regulatory review of therapeutically important drugs, especially when the drugs are the first available treatment or have advantages over existing treatments:

accelerated approval, fast track, breakthrough therapy and priority review.

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Breakthrough therapy status does not guarantee that a product will be eligible for priority review and does not ensure FDA approval.

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• Priority Review :

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In December 2016 the FDA issued a rare pediatric disease priority review voucher to us in connection with the approval of SPINRAZA.

Additionally, as part of our acquisition of Reata in September 2023 we obtained a rare pediatric disease priority review voucher in connection with the approval of SKYCLARYS, which was approved by the FDA in February 2023.

POST-MARKETING STUDIES

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In such a case, the sponsor may be required to establish rigorous systems to assure use of the product under safe conditions.

These systems are usually referred to as Risk Evaluation and Mitigation Strategies (REMS).

These systems are usually referred to as REMS.

The FDA can impose financial penalties for failing to comply with certain post-marketing commitments, including REMS.

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Side effects or adverse events that are reported during clinical trials can delay, impede or prevent marketing approval.

Based on new safety information that emerges after approval, the FDA can mandate product labeling changes, impose a new REMS or the addition of elements to an existing REMS, require new post-marketing studies (including additional clinical trials) or suspend or withdraw approval of the product.

These requirements may affect our ability to maintain marketing approval of our products or require us to

make significant expenditures to obtain or maintain such approvals.

Based on new safety information that emerges after approval, the FDA can mandate product labeling changes, impose a new REMS or the addition of elements to

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an existing REMS, require new post-marketing studies (including additional clinical trials) or suspend or withdraw approval of the product.

These requirements may affect our ability to maintain marketing approval of our products or require us to make significant expenditures to obtain or maintain such approvals.

APPROVAL OF CHANGES TO AN APPROVED PRODUCT

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Some of our marketed products meet this definition and are regulated under this framework and similar regulations outside the U.S., and we expect that some of our pipeline product candidates may be evaluated for regulatory approval under this framework as well.

In May 2017 new regulations governing medical devices (MDR) and in-vitro diagnostic medical devices (IVDR) entered into force in the E.U.

The MDR regulations became applicable in May 2021 and the

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IVDR regulations became applicable in May 2022.

In May 2017 new regulations governing medical devices and in-vitro diagnostic medical devices entered into force in the E.U.

The medical devices regulations became applicable in May 2021 and the in-vitro diagnostic medical devices regulations became applicable in May 2022.

All products covered by these regulations will be required to comply with them at the end of the transitional periods.

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member state only;

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• a decentralized procedure, where applicants submit identical applications to several E.U.

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As in the U.S., the E.U.

also has distinct approaches intended to optimize the regulatory pathways for therapeutically important drugs, including the Priority Medicines Evaluation Scheme (PRIME), accelerated assessment and conditional marketing authorization.

PRIME is intended to provide additional support to medicine developers throughout the development process.

also has distinct approaches intended to optimize the regulatory pathways for therapeutically important drugs, including the Priority Medicines Evaluation Scheme, accelerated assessment and conditional marketing authorization.

Priority Medicines Evaluation Scheme is intended to provide additional support to medicine developers throughout the development process.

Regulatory review timelines in the E.U.

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Marketing authorization holders have an obligation to inform regulatory agencies of any new information which may influence the evaluation of benefits and risks of the medicinal product concerned.

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In the U.S., the E.U.

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If, after receiving approval from regulatory agencies, a company makes a material change in manufacturing equipment, location or process, additional regulatory review and approval may be required.

We also must adhere to current Good Manufacturing Practices (cGMP) and product-specific regulations enforced by regulatory agencies following product approval.

We also must adhere to current GMP and product-specific regulations enforced by regulatory agencies following product approval.

The FDA, the EMA and other regulatory agencies also conduct periodic visits to re-inspect equipment, facilities and processes following the initial approval of a product.

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GOOD CLINICAL PRACTICES

The FDA, the EMA and other regulatory agencies promulgate regulations and standards for designing, conducting, monitoring, auditing and reporting the results of clinical trials to ensure that the data and results are accurate and that the rights and welfare of trial participants are adequately protected (commonly referred to as current Good Clinical Practices (cGCP)).

Regulatory agencies enforce cGCP through periodic inspections of trial sponsors, principal investigators and trial sites, contract research organizations (CROs) and institutional review boards.

If our studies fail to comply with applicable cGCP guidelines, the clinical data generated in our clinical trials may be deemed unreliable and relevant regulatory agencies may require us to perform additional clinical trials before approving our marketing applications.

Regulatory agencies enforce current GCP through periodic inspections of trial sponsors, principal investigators and trial sites, CROs and institutional review boards.

If our studies fail to comply with applicable current GCP guidelines, the clinical data generated in our clinical trials may be deemed unreliable and relevant regulatory agencies may require us to perform additional clinical trials before approving our marketing applications.

Noncompliance can also result in civil or criminal sanctions.

We rely on third-parties, including CROs, to carry out many of our clinical trial-related activities.

Failure of such third-parties to comply with cGCP can likewise result in rejection of our clinical trial data or other sanctions.

Failure of such third-parties to comply with current GCP can likewise result in rejection of our clinical trial data or other sanctions.

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In April 2014 the EC adopted a new Clinical Trial Regulation, which was entered into force in June 2014 but did not apply until January 2022.

There are transitional provisions for clinical trials which are ongoing at the date of application.

Clinical trial applications may also continue to be made under the

Clinical Trial Directive (the existing regulatory framework) until January 2023.

Clinical trial applications could be made under the Clinical Trial Directive (the existing regulatory framework) through January 2023.

All clinical trials must fully comply with the Clinical Trial Regulation by January 2025.

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APPROVAL OF BIOSIMILARS

the Patient Protection and Affordable Care Act (PPACA) amended the Public Health Service Act (PHSA) to authorize the FDA to approve biological products, referred to as biosimilars or follow-on biologics, that are shown to be "highly similar" to previously approved biological products based upon potentially abbreviated data packages.

the PPACA amended the PHS Act to authorize the FDA to approve biological products, referred to as biosimilars or follow-on biologics, that are shown to be "highly similar" to previously approved biological products based upon potentially abbreviated data packages.

The biosimilar must show it has no clinically meaningful differences in terms of safety and effectiveness from the reference product, and only minor differences in clinically inactive components are allowable in biosimilar products.

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Orphan Drug Act, the FDA may grant orphan drug designation to drugs or biologics intended to treat a “rare disease or condition,” which generally is a disease or condition that affects fewer than 200,000 individuals in the U.S.

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which has an orphan drug designation subsequently receives an initial FDA approval for the indication for which it has such designation, the product is entitled to orphan exclusivity, i.e., the FDA may not approve any other applications to market the same drug for the same indication for a period of seven years following marketing approval, except in certain very limited circumstances, such as if the later product is shown to be clinically superior to the orphan product.

If a product which has an orphan drug designation subsequently receives an initial FDA approval for the indication for which it has such designation, the product is entitled to orphan exclusivity, i.e., the FDA may not approve any other applications to market the same drug for the same indication for a period of seven years following marketing approval, except in certain very limited circumstances, such as if the later product is shown to be clinically superior to the orphan product.

Legislation similar to the U.S.

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SPINRAZA has been granted orphan drug designation in the U.S., the E.U.

QALSODY and SKYCLARYS have been granted orphan drug designation in the U.S.

REGULATION PERTAINING TO PRICING AND REIMBURSEMENT

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Other payors, including managed care organizations, health insurers, pharmacy benefit managers, government health administration authorities and private health insurers, seek price discounts or rebates in connection with the placement of our products on their formularies and, in some cases, may impose restrictions on access, coverage or pricing of particular drugs based on perceived value.

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WITHIN THE U.S.

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Under the Medicaid Drug Rebate Program, we are required to pay a rebate for each unit of product reimbursed by the state Medicaid programs.

The amount of the rebate is established by law and is adjusted upward if the average manufacturer price (AMP) increases more than inflation (measured by the Consumer Price Index - Urban).

The amount of the rebate is established by law and is adjusted upward if the AMP increases more than inflation (measured by the Consumer Price Index - Urban).

The rebate amount is calculated each quarter based on our report of current AMP and best price for each of our products to the CMS.

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Medicare Part B generally covers drugs that must be administered by physicians or other health care practitioners, are provided in connection with certain durable medical equipment or are certain oral anti-cancer drugs and certain oral immunosuppressive drugs.

Medicare Part B pays for such drugs under a payment methodology based on the average sales price (ASP) of the drugs.

Manufacturers, including us, are required to provide ASP information to the CMS on a quarterly basis.

Medicare Part B pays for such drugs under a payment methodology based on the average sales price of the drugs.

Manufacturers, including us, are required to provide average sales price information to the CMS on a quarterly basis.

The manufacturer-submitted information is used to calculate Medicare payment rates.

If a manufacturer is found to have made a misrepresentation in the reporting of ASP, the governing statute provides for civil monetary penalties.

If a manufacturer is found to have made a misrepresentation in the reporting of average sales price, the governing statute provides for civil monetary penalties.

Medicare Part D provides coverage to enrolled Medicare patients for self-administered drugs (i.e., drugs that are not administered by a physician).

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In addition, manufacturers, including us, are required to provide to the CMS a discount of up to 70.0% on brand name prescription drugs utilized by Medicare Part D beneficiaries when those beneficiaries reach the coverage gap in their drug benefits.

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beginning in 2022 for Part D and 2023 for Part B, and (iii) Medicare Part D redesign which replaces the current coverage gap provisions and establishes a $2,000 cap for out-of-pocket costs for Medicare beneficiaries beginning in 2025, with manufacturers being responsible for 10.0% of costs up to the $2,000 cap and 20.0% after that cap is reached.

On August 16, 2022, President Biden signed into law the IRA, which provides for (i) the government to negotiate prices for select high-cost Medicare Part D drugs (beginning in 2026) and Part B drugs (beginning in 2028), (ii) manufacturers to pay a rebate for Medicare Part B and Part D drugs when prices increase faster than inflation beginning in 2022 for Part D and 2023 for Part B, and (iii) Medicare Part D redesign which replaces the current coverage gap provisions and establishes a $2,000 cap for out-of-pocket costs for Medicare beneficiaries beginning in 2025, with manufacturers being responsible for 10.0% of costs up to the $2,000 cap and 20.0% after that cap is reached.

The result of these forthcoming changes for manufacturers, including us, may include:

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• Federal Agency Discounted Pricing :

Our products are subject to discounted pricing when purchased by federal agencies via the Federal Supply Schedule (FSS).

FSS participation is required for our products to be covered and reimbursed by the Veterans Administration (VA), Department of Defense, Coast Guard and Public Health Service (PHS).

Our products are subject to discounted pricing when purchased by federal agencies via the FSS.

FSS participation is required for our products to be covered and reimbursed by the VA, Department of Defense, Coast Guard and PHS.

Coverage under Medicaid, Medicare and the PHS pharmaceutical pricing program is also conditioned upon FSS participation.

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To maintain coverage of our products under the Medicaid Drug Rebate Program and Medicare Part B, we are required to extend significant discounts to certain covered entities that purchase products under Section 340B of the PHS pharmaceutical pricing program.

Purchasers eligible for discounts include hospitals that serve a disproportionate share of financially needy patients, community health clinics and other entities that receive certain types of grants under the PHSA.

our products, we must agree to charge a price that will not exceed the amount determined under statute (the “ceiling price”) when we sell outpatient drugs to these covered entities.

Purchasers eligible for discounts include hospitals that serve a disproportionate share of financially needy patients, community health clinics and

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other entities that receive certain types of grants under the PHS Act.

For all of our products, we must agree to charge a price that will not exceed the amount determined under statute (the “ceiling price”) when we sell outpatient drugs to these covered entities.

In addition, we may, but are not required to, offer these covered entities a price lower than the 340B ceiling price.

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Violations of fraud and abuse laws may be punishable by criminal or civil sanctions, including fines and civil monetary penalties, and exclusion from federal health care programs (including Medicare and Medicaid).

In the U.S., federal and state authorities are paying increased attention to enforcement of these laws

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within the pharmaceutical industry and private individuals have been active in alleging violations of the laws and bringing suits on behalf of the government under the federal civil False Claims Act.

In the U.S., federal and state authorities are paying increased attention to enforcement of these laws within the pharmaceutical industry and private individuals have been active in alleging violations of the laws and bringing suits on behalf of the government under the federal civil False Claims Act.

If we were subject to allegations concerning, or were convicted of violating, these laws, our business could be harmed.

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Those laws include the U.S.

Foreign Corrupt Practices Act (FCPA), which prohibits U.S.

FCPA, which prohibits U.S.

companies and their representatives from paying, offering to pay, promising to pay or authorizing the payment of anything of value to any foreign government official, government staff member, political party or political candidate for the purpose of obtaining or retaining business or to otherwise obtain favorable treatment or influence a person working in an official capacity.

In many countries, the health care professionals we regularly interact with may meet the FCPA's definition of a foreign government official.

The FCPA also requires public companies to make and keep books and records that accurately and fairly reflect their transactions and to devise and maintain an adequate system of internal accounting controls.

The FCPA also requires public companies to make and keep books and records that

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accurately and fairly reflect their transactions and to devise and maintain an adequate system of internal accounting controls.

The laws to which we are subject also include the U.K.

Bribery Act 2010 (Bribery Act), which proscribes giving and receiving bribes in the public

and private sectors, bribing a foreign public official and failing to have adequate procedures to prevent employees and other agents from giving bribes.

Bribery Act 2010 (Bribery Act), which proscribes giving and receiving bribes in the public and private sectors, bribing a foreign public official and failing to have adequate procedures to prevent employees and other agents from giving bribes.

companies that conduct business in the U.K.

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National Institutes of Health Guidelines for Research Involving Recombinant DNA Molecules (NIH Guidelines).

By local ordinance, we are required to, among other things, comply with the NIH Guidelines in relation to our facilities in RTP, NC and are required to operate pursuant to certain permits.

By local ordinance, we are required to, among other things, comply with the NIH Guidelines in relation to our facilities in RTP, North Carolina and are required to operate pursuant to certain permits.

Our present and future business has been and will continue to be subject to various other laws and regulations.

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The European Parliament and the Council of the E.U.

adopted a comprehensive general data privacy regulation (GDPR) in 2016 to replace the current E.U.

adopted a comprehensive GDPR in 2016 to replace the current E.U.

Data Protection Directive and related country-specific legislation.

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to the U.S., provides an enforcement authority and imposes large penalties for noncompliance, including the potential for fines of up to €20.0 million or 4.0% of the annual global revenue of the infringer, whichever is greater.

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In addition, several U.S.

jurisdictions have similar data privacy laws, such as the California Consumer Privacy Act and California Privacy Rights Act.

MANUFACTURING

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We believe that our manufacturing facilities, together with the third-party contract manufacturing organizations we outsource to, currently provide sufficient capacity for our products and to Samsung Bioepis, our collaboration partner that develops, manufactures and markets biosimilar products, and other strategic contract manufacturing partners.

In March 2021 we announced our plans to build a new gene therapy manufacturing facility in RTP, NC to support our gene therapy pipeline across multiple therapeutic areas.

The new manufacturing facility will be approximately 197,000 square feet and is expected to be operational by the end of 2023, with an estimated total investment of approximately $195.0 million.

Construction for this new facility began during the fourth quarter of 2021.

In the fourth quarter of 2021 we began construction of a new gene therapy manufacturing facility in RTP, North Carolina to support our gene therapy pipeline across multiple therapeutic areas.

The new manufacturing facility will be approximately 197,000 square feet with an estimated total investment of approximately $195.0 million.

As we continue to advance our research and development prioritization efforts, which includes refocusing our investment in gene therapy, we are evaluating several alternative uses for this facility.

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MANUFACTURING FACILITIES

Our drug substance manufacturing facilities include:

Facility Drug Substance Manufactured

Our manufacturing facilities include:

Facility Product Manufactured

RTP, North Carolina AVONEX

Solothurn, Switzerland ADUHELM

Solothurn, Switzerland LEQEMBI

* Other includes products manufactured for contract manufacturing partners.

In addition to our drug substance manufacturing facilities, we have a drug product manufacturing facility and supporting infrastructure in RTP, NC, including a parenteral facility and an oral solid dose products manufacturing facility.

** We began manufacturing TYSABRI at the Solothurn manufacturing facility in 2024.

In addition to our drug substance manufacturing facilities, we have a drug product manufacturing facility and supporting infrastructure in RTP, North Carolina, including a parenteral facility and an oral solid dose products manufacturing facility.

The parenteral facility adds capabilities and capacity for filling biologics into vials and is used for filling product candidates.

The oral solid dose products facility can supplement our outsourced small molecule manufacturing capabilities.

We also have an oligonucleotide synthesis manufacturing facility in RTP, NC.

This facility gives us the capability to manufacture ASO candidates currently in our clinical pipeline.

In order to support our future growth and drug development pipeline, we are building a large-scale biologics manufacturing facility in Solothurn, Switzerland.

In the second quarter of 2021 a portion of the facility received a Good Manufacturing Practice (GMP) multi-product license from the Swiss Agency for

Therapeutic Products (SWISSMEDIC).

We also have an oligonucleotide synthesis manufacturing facility in RTP, North Carolina.

This facility gives us the capability to manufacture both commercial and clinical ASO's and beginning in 2024 this facility will manufacture SPINRAZA.

In order to support our future growth and drug development pipeline, we built a large-scale biologics manufacturing facility in Solothurn, Switzerland.

In the second quarter of 2021 a portion of the facility (the first manufacturing suite) received a GMP multi-product license from the SWISSMEDIC and was placed into service.

The second manufacturing suite became operational in January 2024.

Solothurn has been approved for the manufacture of ADUHELM and LEQEMBI by the FDA.

We estimate the second manufacturing suite at the Solothurn facility will be operational by the end of 2023.

Genentech is responsible for all worldwide manufacturing activities for bulk RITUXAN, RITUXAN HYCELA and GAZYVA and has sourced the manufacture of certain bulk RITUXAN, RITUXAN HYCELA and GAZYVA requirements to a third party.

Ionis supplies the active pharmaceutical ingredient (API) for SPINRAZA.

Alkermes currently supplies both VUMERITY and FAMPYRA to us pursuant to separate supply agreements.

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We have elected to initiate a technology transfer and, following a transition period, to manufacture VUMERITY or have VUMERITY manufactured by a third party we have engaged in exchange for paying an increased royalty rate to Alkermes on any portion of future worldwide net commercial sales of VUMERITY that is manufactured by us or our designee.

In October 2022 we entered into a new supply agreement with Alkermes for FAMPYRA.

Acorda previously supplied FAMPYRA to us pursuant to a sublicensing arrangement with Alkermes, which was terminated in October 2022 as a result of an arbitration outcome between Acorda and Alkermes.

In January 2023 we entered into a new supply agreement with Alkermes for FAMPYRA through January 2025.

In December 2023 Alkermes entered into a definitive agreement to sell its development and manufacturing facility to Novo Nordisk, which is expected to close in mid-2024.

Alkermes and Novo Nordisk plan to enter into subcontracting arrangements to continue work currently performed at the facility for a period of time after closing the transaction, which may continue through the end of 2025.

THIRD-PARTY SUPPLIERS AND MANUFACTURERS

We principally use third parties to manufacture the API and the final product for our small molecule products and product candidates, including TECFIDERA and FUMADERM, and the final drug product for our large molecule products and, to a lesser extent, product candidates.

We principally use third parties to manufacture the active pharmaceutical ingredient and the final product for our small molecule products and product candidates, including TECFIDERA and FUMADERM, and the final drug product for our large molecule products and, to a lesser extent, product candidates.

We source the majority of our fill-finish and all of our final product assembly and storage operations for our products, along with a substantial part of our label and packaging operations, to a concentrated group of third-party contract manufacturing organizations.

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Continuity of supply of such raw materials, devices and supplies is assured through inventory management and dual sourcing as appropriate.

Our third-party service providers, suppliers and manufacturers may be subject to routine cGMP inspections by the FDA or comparable agencies in other jurisdictions and undergo assessment and certification by our quality management group.

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In addition, one of our contract manufacturers for IMRALDI and BENEPALI entered into a proposed acquisition by a third party, which is expected to close at the end of 2024.

We are currently evaluating the impact this will have on our biosimilars business.

ESG AND CLIMATE-RELATED MATTERS

Our environmental, social and governance (ESG) efforts prioritize climate, health and equity, with a focus on vulnerable populations, as well as ongoing leadership in sustainability, governance, transparency and disclosure.

We remain committed to reducing our environmental footprint by eliminating harmful emissions and by minimizing resources used to manufacture our products.

Since 2014 we have taken responsibility for our impact on climate change by matching 100% of our electricity usage with renewable energy, credits and offsets, driving efficiency initiatives internally and working with our suppliers.

Green chemistry is embraced throughout our company, continually exploring new ways to make our drug development processes safer, more efficient and more sustainable while also saving resources.

ESG oversight is formally embedded into our Board of Director's governance principles and includes an annual review of our ESG strategy and short-and long-term goals.

We regularly review our environmental commitments within the landscape of our business performance, rising costs and supply chain challenges.

We remain committed to engaging employees and suppliers and collaborating with renowned institutions to advance the science and action to improve health outcomes.

We continue to refine our ESG strategy and programs so they are designed to deliver meaningful results in the areas where we believe we can have the greatest impact.

We have bolstered our efforts in access and health equity and refocused our Foundation efforts on the communities where we operate.

Our environmental strategy is designed to balance impact in line with investment and to drive sustainability into our core operations.

ESG oversight is formally embedded into our Board of Director's corporate governance principles and our Board of Directors annually review our ESG strategy and short-and long-term goals.

We regularly review our environmental commitments within the context of our business performance, rising costs and supply chain challenges.

We remain committed to engaging employees and suppliers.

As part of our broader commitment to these priorities, we continue to tie a portion of our employees' and executive officers' compensation to advancing our ESG efforts.

We strive to comply in all material respects with applicable laws and regulations concerning the environment.

While it is impossible to predict accurately the future costs associated with environmental compliance and potential remediation activities, compliance with environmental laws is not expected to require significant capital expenditures and has not had, and is not expected to have, a material adverse effect on our operations or competitive position.

While it is impossible to predict accurately the future costs associated with environmental compliance and potential remediation activities, compliance with environmental laws is not currently expected to require significant capital expenditures and has not had, and is not expected to have, a material adverse effect on our operations or competitive position.

Our Executive Committee has responsibility for evaluating the impact of climate change on the business and overseeing actions taken by the company to limit its adverse impact on the environment.

Our Enterprise Risk Management (ERM) framework is designed to ensure climate-related risks and opportunities are integrated into our overall business strategy.

Our ERM team monitors strategic climate-related risks across all aspects of our business and utilizes climate scenarios as part of its

On an annual basis, the ERM team evaluates identified risks, including any climate-related physical and transitional risks, by engaging leaders across the company.

The ERM team provides annual updates on their findings and activities to our Executive Committee and Board of Directors.

Our ERM framework is designed to ensure climate-related risks and opportunities are integrated into our overall business strategy.

Our ERM team monitors strategic climate-related risks across all aspects of our business and utilizes climate scenarios as part of its assessments.

The ERM team evaluates identified risks, including any climate-related physical and transitional risks, by engaging leaders across the company.

RISK MANAGEMENT

Addressing ESG matters is part of our long-term global strategy and investment in our future and we have seen increased interest from stakeholders and investors on our ESG practices.

While we continue to to advance our ESG efforts, there is no certainty that we will manage ESG matters in ways that successfully meet rapidly changing expectations from investors, regulators, third party rankings firms, customers and society as a whole.

While we continue to advance our ESG efforts, there is no certainty that we will manage ESG matters in ways that successfully meet rapidly changing expectations from investors, regulators, third party rankings firms, customers and society as a whole.

Our inability to manage ESG matters in accordance with expectations can negatively impact our reputation and business.

CLIMATE RISK MANAGEMENT

We identify climate risk as the risk of loss arising from climate change and is comprised of both physical risk and transition risk.

Physical risk considers how the physical impacts of climate change (e.g., increased storms, drought, fires, floods) can directly damage physical assets or otherwise impact their value or productivity.

Transition risk considers how changes in policy.

regulations, culture, technology, business practices and market preferences to address climate change (e.g., carbon pricing policies, power generation shifts from fossil fuels to renewable energy) can lead to changes in the value of assets and businesses.

Disruption in supply chains, changing customer expectations in the biosimilar market and potential shifts in the regulatory environment that disadvantage the use of fossil fuels, may make it difficult for us to fulfill business obligations or cause us to incur substantial expense.

Identified material risks and opportunities are reported to our ERM team, which reports to our Executive Committee and Board of Directors.

We identify climate risk as the risk of loss arising from climate change which comprises both physical risk and transition risk.

Physical risk considers how the physical impacts of climate change (e.g., increased frequency and intensity of storms, drought, fires, floods) can directly damage physical assets or otherwise impact their value or productivity.

Transition risk considers how changes in policy, regulations, culture, technology, business practices and market preferences to address climate change (e.g., carbon pricing policies, power generation shifts from fossil fuels to renewable energy) can lead to changes in the value of assets and businesses.

Disruption in supply chains, changing customer expectations in the biosimilars market and potential shifts in the regulatory environment that disadvantage the use of fossil fuels, PFAS or other materials may make it difficult for us to fulfill business obligations or cause us to incur substantial expense.

Identified climate-related material risks and opportunities are reported to our ERM team, which reports to our Executive Committee and Board of Directors.

We consider and address those risks and opportunities that are financially material and may impact our business model, as well as mitigation measures that are in place or need to be adopted.

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Risk Factors included in this report.

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CALIFORNIA CLIMATE LEGISLATION

In October 2023 California signed into law the CCDAA and the CRFRA.

These new environmental disclosure laws will each impose additional climate-related reporting requirements on large companies conducting business in the state of California.

Beginning in 2026 the CCDAA will require companies meeting certain revenue thresholds to publicly disclose Scope 1 and Scope 2 GHG emissions for the prior fiscal year.

Starting in 2027 companies meeting certain revenue thresholds will also need to publicly disclose Scope 3 GHG emissions for the prior fiscal year.

Assurance requirements will also apply to these public disclosures and will be phased-in over time.

The CRFRA will require companies meeting certain revenue thresholds to prepare biennial reports disclosing climate-related financial risk, as well as mitigation measures the company has adopted to reduce this risk.

The first climate-related financial risk reports are due by January 1, 2026.

We expect to be required to comply with both the CCDAA and CRFRA and are actively evaluating the requirements under these acts in order to prepare for compliance.

At this time, we expect we may incur additional costs associated with these new laws, including costs associated with implementing or updating existing controls and procedures to collect and maintain required data, as well as costs associated with retaining third-party assurance providers.

HUMAN CAPITAL

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and approximately 3,430 employees were employed in foreign countries.

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DIVERSITY, EQUITY AND INCLUSION

At Biogen, prejudice, racism and intolerance are unacceptable.

We are committed to Diversity, Equity and Inclusion (DE&I) across all aspects of our organization, including recruitment, hiring, promotion, retention and development practices.

We are committed to DE&I across all aspects of our organization, including recruitment, hiring, promotion, retention and development practices.

As of December 31, 2023, 31.2% of Biogen’s manager-level and above positions were held by ethnic or racial minorities in the U.S.

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Globally, 48.6% of Biogen’s positions at director-level and above were held by women as of December 31, 2023.

Our DE&I strategy outlines actionable steps to deepen our commitment across the business, building upon a strong foundation.

Our DE&I strategy outlines what we believe to be actionable steps to deepen our commitment across the business, building upon a strong foundation.

This plan includes the strategy to build our talent and strengthen our leadership, improve health outcomes for underserved communities in the disease areas we treat and contribute to the communities impacting our employees and patients.

We plan to create greater awareness and capability in our organization through leadership accountability and transparency.

To establish and progress this strategy, we rely on a cross-company governing body of employees known as the Diversity, Equity & Inclusion Strategic Council.

We are honored to be recognized as an employer of choice.

For the fifth consecutive year, we scored 100% on the Disability:IN's Disability Equality Index, which measures our policies and practices related to disability inclusion.

Additionally, for the third consecutive year, we were awarded the DI-NC Employer Award by Disability:IN North Carolina for our commitment to champion and invest in disability inclusion at the affiliate and national levels.

For the ninth consecutive year, we were recognized as a Best Place to Work for LGBTQ+ Equality by the Human Rights Campaign, scoring 100% on their Corporate Equality Index.

For the sixth consecutive year, we scored 100% on the Disability:IN's Disability Equality Index, which measures our policies and practices related to disability inclusion.

Additionally, for the fourth consecutive year, we were awarded the DI-NC Employer Award by Disability:IN North Carolina for our commitment to champion and invest in disability inclusion at the affiliate and national levels.

For the tenth consecutive year, we were recognized as a Best Place to Work for LGBTQ+ Equality by the Human Rights Campaign, scoring 100% on their Corporate Equality Index.

STRENGTHENING OUR GLOBAL COMPETENCY

We are committed to strengthening the DE&I awareness and capability of our employees.

We have focused on ensuring that our employees have the resources and learning they need to contribute to our strategy.

We have focused on giving our employees the resources and learning they need to contribute to our strategy.

Our people managers are trained on inclusive recruiting and hiring and our global employees are trained on DE&I curriculum.

In 2022 we introduced GlobeSmart®, a tool to enhance cross-cultural collaboration, increase cultural agility and further connect our global teams.

Our people leaders have used GlobeSmart®, allowing them to explore different working styles, perspectives and approaches that exist around the globe, getting actionable, personalized advice for better collaboration and teamwork across cultures, and

exploring new ways for teams to build trust, strengthen collaboration and leverage diversity.

PHILOSOPHY ON PAY EQUITY

We are committed to ensuring our employees receive equal pay for equal work.

We are committed to providing our employees with equal pay for equal work.

We establish components and ranges of compensation based on market and benchmark data.

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and individual, business unit and company performance.

In addition, we are committed to providing flexible benefits designed to allow our diverse global workforce to have reward opportunities that meet their varied needs so that they are inspired to perform their best on behalf of patients and stockholders each day.

In addition, we are committed to

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providing flexible benefits designed to allow our diverse global workforce to have reward opportunities that meet their varied needs so that they are inspired to perform their best on behalf of patients and stockholders each day.

We regularly review our compensation practices and analyze the equity of compensation decisions, for individual employees and our workforce as a whole.

In 2022 we shared the results of a global gender pay assessment, analyzing pay at the executive, management and other professional levels.

We institute measures, such as communications and trainings, to recognize, interrupt and prevent bias in hiring, performance management and compensation decisions and we provide resources to further develop managers and leaders to help them make equitable decisions about pay.

RECRUITMENT AND RETENTION

A business-wide priority is to strengthen our culture and the employee experience.

To address a highly dynamic labor market, we have examined our global benefits and seek to provide competitive comprehensive total rewards to our employees.

We have also conducted an affordability analysis to benchmark whether our benefits program costs are equitable.

We examined employee total rewards across four pillars:

physical, financial, emotional and social well-being.

We continue to evolve our programs to meet our employees’ health and wellness needs, which we believe is essential to attract and retain employees of the highest caliber.

SUCCESSION PLANNING

Each year we conduct a talent review across our global enterprise that includes, among other important topics, a review of succession plans for many of our roles.

To help ensure the long-term continuity of our business, we actively manage the development of talent to fill the roles that are most critical to the ongoing success of our Company.

In addition, each year our Board of Directors reviews the succession plan for our executives.

TALENT AND DEVELOPMENT

Many factors influence employee success and well-being.

We foster a workplace to allow employees to deliver on our shared mission while helping to mitigate their challenges.

We work to foster a workplace to allow employees to deliver on our shared mission while helping to mitigate their challenges.

From career development to wellness to workplace environment, there are many opportunities to meet employee needs, and to build a workplace where people are empowered to learn, grow and build rewarding careers.

Our employees are encouraged to take advantage of an array of professional development resources.

Managers coach employees for performance, and also engage in employee development discussions to support growth and learning.

Managers are trained to coach employees for performance, and also engage in employee development discussions to support growth and learning.

Opportunities for ongoing learning can contribute to employee related engagement and success.

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Through Biogen University we offer more than 1,000 instructor-based courses, of which approximately 200 are available virtually.

Through LinkedIn Learning we provided employees with access

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to more than 20,000 on-demand learning modules in 11 languages:

English, German, French, Spanish, Japanese, Portuguese, Italian, Dutch, Polish, Turkish and Mandarin.

Through LinkedIn Learning we provided employees with access to more than 22,000 on-demand learning modules in 13 languages.

To create and sustain a workplace as diverse and inclusive as the patients we serve, we offer programs that invest in our talent pipeline and in our current leaders, including:

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Preparing high-potential individual contributors for first-level leadership roles.

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Coaching program available to support individuals as they work toward enhancing their impact in the organization.

Our Employee Resource Networks (ERNs) provide invaluable opportunities for employees to share knowledge and build connections.

Our ERNs provide invaluable opportunities for employees to share knowledge and build connections.

Our current ERNs include:

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Advances climate, health and equity at work, in employees' personal lives and in the communities where we live and work.

We continue to evolve our programs to meet our employees’ health and wellness needs, which we believe is essential to attract and retain employees of the highest caliber.

We have refreshed our flexible working arrangement policies to allow for more flexibility around work hours to help employees balance the demands of their work and home lives, shifted many of our on-site wellness services to virtual, including virtual behavior health, nutrition, fitness and overall well-being classes and counseling, rolled out the Headspace meditation app globally at no cost, provided workshops and programming to help employees cope with stress, isolation and building resilience, along with financial planning workshops and counseling sessions, expanded our caregiver services to meet the growing needs of our employees and provided additional holidays and time off for recharging, voting and volunteering.

Employee Surveys

CULTURE AND ENGAGEMENT

We utilize an employee survey program to pulse employees through email and mobile apps as well as provide an opportunity for commentary and facilitate feedback to questions.

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We use their perspectives to guide us to take actions that improve engagement and support and help maintain our reputation as a great place to work for all our employees.

An example of such an action was our 2022 Wellness Week, a weeklong mid-year shutdown.

Succession Planning

Each year we conduct a talent review across our global enterprise that includes, among other important topics, a review of succession plans for many of our roles.

To help ensure the long-term continuity of our business, we actively manage the development of talent to fill the roles that are most critical to the

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ongoing success of our company.

In addition, each year our Board of Directors reviews the succession plan for our executives.

WORKPLACE HEALTH AND SAFETY

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By engaging and empowering our employees through such programs, we believe that we can help change how the entire industry approaches safety performance and risk management.

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INFORMATION ABOUT OUR EXECUTIVE OFFICERS (as of February 13, 2024)

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Viehbacher President, Chief Executive Officer 63 2022

Alexander Executive Vice President, Chief Legal Officer and Secretary 66 2006

Alexander Executive Vice President, Chief Legal Officer

McDonnell Executive Vice President and Chief Financial Officer 60 2020

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Executive Vice President, Head of Development 56 2020

Jane Grogan, Ph.D.

Executive Vice President, Head of Research 57 2023

Adam Keeney, Ph.D.

Executive Vice President, Head of Corporate Development 47 2023

Kramer Senior Vice President, Chief Accounting Officer 58 2018

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He is also a trustee of Northeastern University and a member of the board of fellows at Stanford Medical School.

Public Company Boards

l PureTech Health Plc.

l Queen's University in Kingston, Ontario, Canada, B.A.

Alexander has served as our Executive Vice President, Chief Legal Officer and Secretary since April 2018.

Alexander has served as our Executive Vice President, Chief Legal Officer since April 2018.

Prior to that, Ms.

Alexander served as our Executive Vice President, Chief Legal, Corporate Services and Secretary from March 2017 to March 2018, as our Executive Vice President, Chief Legal Officer and Secretary from December 2011 to March 2017 and as our Executive Vice President, General Counsel and Corporate Secretary from 2006 to December 2011.

Alexander served as our Executive Vice President, Chief Legal and Corporate Services from March 2017 to March 2018, as our Executive Vice President, Chief Legal Officer and Secretary from December 2011 to March 2017 and as our Executive Vice President, General Counsel and Corporate Secretary from 2006 to December 2011.

Prior to joining Biogen, Ms.

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l Boston University School of Law, J.D.

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McDonnell has served as our Executive Vice President and Chief Financial Officer since August 2020.

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l The George Washington University, Ph.D.

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Izzar has served as our Executive Vice President, Head of Global Product Strategy and Commercialization since July 2021.

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l University of Mumbai, Doctor of Medicine (M.D.)

Jane Grogan, Ph.D.

Grogan has served as our Executive Vice President and Head of Development since September 2023.

Grogan most recently served as the Chief Scientific Officer at Graphite Bio from 2021 to 2023 and ArsenalBio from 2019 to 2021, both cell and gene therapy companies.

From 2004 to 2019 Dr.

Grogan held several roles in increasing seniority at Genentech across Immunology and Immuno-oncology, covering research strategies and drug development across Rheumatoid Arthritis, Lupus, MS, Inflammatory Bowel Disease and Cancer.

l Leiden University, Ph.D.

in Immunology

l University of Melbourne, B.Sc in Biochemistry and Pharmacology

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Adam Keeney, Ph.D.

Keeney has served as our Executive Vice President and Head of Corporate Development since April 2023.

Keeney brings more than 20 years of experience leading R&D, business development and strategy organizations at industry-leading companies within biotech and large pharma, Dr.

Keeney most recently served as the Chief Executive Officer of NodThera, a clinical stage biotech company focused on chronic inflammation from 2018 to 2022.

Prior to NodThera, Dr.

Keeney was at Sanofi from 2014 to 2018 where he had responsibility for all of Sanofi Gezyme's business development activities, including early- and late-stage deals across therapeutic areas and modalities, successfully completing several significant transactions.

From 2004 to 2013 Dr.

Keeney worked at Johnson & Johnson where he held a number of business development roles with increasing responsibility and started his career at Lundbeck as a discovery scientist.

l University of Nottingham, UK, Ph.D.

in Neuropharmacology

l University of Leeds, UK, BSc (Hons)

Kramer has served as our Senior Vice President, Chief Accounting Officer since December 2020.

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l Salem State University, B.B.A.

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AVAILABLE INFORMATION

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Our website address is www.biogen.com.

We make available free of charge through the Investors section of our website our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and all amendments to those reports as soon as reasonably practicable after such material is electronically filed with or furnished to the U.S.

Securities and Exchange Commission.

We include our website address in this report only as an inactive textual reference and do not intend it to be an active link to our website.

The contents of our website are not incorporated into this report.

Table of Conten ts

USE OF WEBSITE TO PROVIDE INFORMATION

From time to time, we have used, and expect in the future to use, our website as a means of disclosing material information to the public in a broad, non-exclusionary manner, including for purposes of the SEC’s Regulation Fair Disclosure (Reg FD).

Financial and other material information regarding the Company is routinely posted on our website and accessible at www.biogen.com.

In order to receive notifications regarding new postings to our website, investors are encouraged to enroll on our website to receive automatic email alerts.

None of the information on our website is incorporated into this report.

T able of Contents

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 1. Business