OUR PURPOSE PIONEERING SCIENCE PATIENTS OUR PEOPLE ENVIRONMENT COMMUNITY REPORTING 40 ADVANCING HEALTH ACCESS AND EQUITY BIOGEN 2021 YEAR IN REVIEW Biogen regularly seeks guidance from PAGs, regulators, clinical researchers, ethicists, physicians and communities, among others, to determine how best to address requests for access to investigational therapies in a way that is consistent with our patient-focused values and compliant with regulatory standards and protocols. We are grateful to everyone who participates in testing our investigational therapies. All participants are encouraged to carefully consider the risks prior to enrollment. Þ LEARN ABOUT CLINICAL RESEARCH Þ LEARN ABOUT PATIENT SAFETY Þ LEARN ABOUT OUR APPROACH TO CLINICAL TRIALS Working to expand access to medicine Therapies with positive results from clinical trials must be approved by a regulatory authority such as the FDA or EMA. We comply with government regulations and engage with regulatory agencies and others to ensure that new and innovative therapies are commercially available to the patients who need them. To provide patients with access to drugs that have not yet become commercially available, we have occasionally been able to offer EAPs. We strive to meet the needs of all patients globally, including those from underserved and underrepresented groups and in low- and middle-income countries. For example, we have worked hard to ensure that SPINRAZA is available in 30 provinces, cities and autonomous regions across China so patients in remote areas like Gansu, Ningxia, Qinghai, Xinjiang and Inner Mongolia are able to access treatment through local hospitals. We maintain Access Programs to treat patients in more than 40 countries. Þ READ MORE ABOUT OUR ACCESS PROGRAMS FEATURE Granting access to tofersen outside of clinical trial We listened to the voices of many patients and their families seeking to gain access to our investigational SOD1-ALS therapy, tofersen, through compassionate use before the study is completed and before tofersen is proven safe and effective. Biogen teams engaged extensively with clinical investigators, ethicists, patient advocates and regulators to explore all potential ethical avenues to provide access to tofersen, outside of the ongoing Phase 3 study. As a result of this wide-ranging engagement, we established a two- part tofersen access program. Beginning in mid-July 2021, after patients in the Phase 3 study who were on placebo transitioned to active therapy and before the safety and efficacy of tofersen was established, compassionate use access was provided for a subset of the SOD1-ALS population with the most rapidly progressive disease. Based on results from the Phase 3 study indicating tofersen safe and effective, we broadened early access to tofersen to all eligible SOD1- ALS patients through our already established EAP. Answering questions about access outside of clinical trials is neither simple nor fast. This is a first for Biogen and reflects the evolution of our thinking about access in rare diseases while standing strong on our principles for ethical and equitable access.