OUR PURPOSE PIONEERING SCIENCE PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING 19 ENHANCING OUR STRATEGIC PORTFOLIO BIOGEN 2021 YEAR IN REVIEW Delivering progress on therapies at the cutting edge of innovation will continue to be at the center of our work, guided by our distinctive capabilities and experience, and driven by our passion to improve lives. Depression Mental health has serious, far-ranging impacts: across the globe, an estimated 280 million people live with depression and more than 700,000 people die from suicide annually. While the COVID-19 pandemic increased demand for treatment, it also started to soften barriers to openly discussing mental health issues, a step in the right direction. Biogen is applying our expertise in neuroscience with the aim of addressing tremendous unmet patient needs around depression. Major depressive disorder (MDD) is a common comorbidity of many diseases represented in our neuroscience portfolio. Monoamine-based antidepressants, which have been the standard of care for chronic treatment of MDD for the past 60 years, can take weeks to offer relief. With the goal of providing new treatment options for MDD and postpartum depression (PPD), we collaborated with Sage Therapeutics, Inc. to jointly develop zuranolone (BIIB125/SAGE-217), an investigational drug dosed once daily for two weeks. Zuranolone has positive data from five randomized clinical studies in MDD. Based on the clinical data and the differentiated profile of zuranolone, we are preparing to start a rolling submission for a New Drug Application in MDD, filing in the U.S. in the first half of 2022. We’re proud to be working to bring a potential new option for patients with MDD and PPD who are seeking timely and meaningful reductions in depressive symptoms. Þ READ MORE ABOUT ZURANOLONE TRIAL RESULTS Also in neuropsychiatry, we expect the Phase 2 readout for BIIB104 in cognitive impairment associated with schizophrenia in mid-2022. Multiple sclerosis (MS) With an estimated 2.8 million people living with MS worldwide 2 , treating this chronic disease has long been at the core of our multi-franchise portfolio. For more than 25 years, we have led in the research and development of new therapies to treat MS, and more than 1.8 million people have been treated with a Biogen disease-modifying therapy. Today, we continue to advance our MS therapies, conduct active clinical trials and offer six marketed therapies for relapsing MS and/or RRMS, including FAMPYRA, which helps to address difficulties with walking. As we look forward to introducing therapies in the future, we are focusing our attention on addressing the multifaceted challenges of MS management and advancing the care of those living with this disease through novel tools, biomarkers and advanced digital capabilities that better assess clinical outcomes, provide prognostic information and improve clinical decision making. – VUMERITY® (diroximel fumarate), which was the number one new relapsing MS oral prescription in the U.S. by the end of 2020, was recommended in 2021 for marketing authorization by the Committee for Medicinal Products for Human Use (CHMP), part of the European Medicines Agency (EMA). We have launched VUMERITY in the U.S. and recently in Europe and are looking forward to launching in additional markets. VUMERITY is our latest fumarate that offers the convenience of an oral medication with the established efficacy TECFIDERA® (dimethyl fumarate). In 2021, VUMERITY also became available and is reimbursed in Israel and was approved in Switzerland for marketing authorization by Swissmedic. Þ READ MORE ABOUT THE EU LAUNCH OF VUMERITY – TYSABRI® (natalizumab): In 2021, we marked 15 years of TYSABRI. In 2021, we also announced EU approval for a subcutaneous formulation of TYSABRI (natalizumab). Now, two routes of administration have the potential to offer flexibility to meet patients’ individual preferences and needs. The subcutaneous option provides a shorter administration time and expands access to treatment for patients and physicians beyond the infusion setting. For the EU healthcare system, the subcutaneous administration is cheaper to administer and requires fewer resources compared to an IV infusion, improving efficiency. Þ READ MORE ABOUT THE NEW ADMINISTRATION PROFILE OF TYSABRI 1. Kaiser Family Foundation (KFF), (2021, February 10). How the COVID-19 pandemic is affecting people’s m ental health and substance abuse . 2. www.nationalmssociety.org, Updated Atlas of MS Shows Over 2.8 Million People Worldwide Have Multiple Sclerosis – with Nearly 1 Million in the US .