Science & Innovation

Early Access

Biogen advances science through the development and approval of medicines to benefit the greatest number of patients in a timely manner.

Clinical Trials

Clinical trials are the main way for patients to access investigational drugs.

Biogen’s clinical trials are conducted to test the safety and effectiveness of investigational drugs so that regulatory authorities — such as the FDA in the United States and the EMA in Europe — can decide whether or not these drugs can be approved as a treatment for a disease. Biogen strives to design and run clinical trials that will provide these regulatory agencies with the data they need to determine if an investigational drug is beneficial to people.


To participate in a clinical trial, a patient must meet the inclusion/exclusion (eligibility) criteria. These criteria are important because they help researchers identify people who can participate and identify a group of people with similar characteristics of a disease. This makes it easier and quicker for researchers to evaluate the investigational drug, potentially leading to faster review and approval.

What is Early Access?

Early access is a potential pathway for patients diagnosed with a serious and/or life-threatening disease or condition to gain access to an investigational product for treatment outside of a clinical trial when no comparable or satisfactory alternative therapy options are available. In these instances, a patient’s treating physician can request an investigational product prior to regulatory approval, where allowed by local laws.

Who is Eligible for Early Access Programs?

Biogen considers granting early access to investigational products when all of the following criteria are met:

  • A patient is diagnosed with a serious and/or life-threatening disease or condition and no comparable or satisfactory alternative therapy is available to treat the disease or condition.
  • The patient is not eligible to participate in a clinical trial.
  • Sufficient data exists where the potential benefits of the treatment outweigh the potential risks for the disease to be treated.
  • There is adequate supply of the investigational product, and providing the investigational product will not interfere with ongoing clinical trials or the overall development program.
  • Investigational access provided in this setting is allowed per local laws and regulations.

Available Early Access Programs

SOD1-ALS: Tofersen (outside United States only)

Update as of May 30, 2024

Tofersen is an antisense asset being evaluated for the potential treatment of SOD1-ALS. Based on totality of the data from the Phase 3 VALOR study and its open-label extension, Biogen is actively engaging with regulators, the medical community, patient advocacy groups, and other key stakeholders around the world to determine potential next steps.

In light of the critical unmet medical need, Biogen has provided access to tofersen through an early access program (EAP) since July 2021, in countries where such programs are permitted by local regulations and future access may be secured. EAPs enable participants to gain access to a medicine free of charge before the treatment is licensed commercially. If a clear path forward for tofersen is not established, or if another controlled trial is required by regulators, Biogen may revise or discontinue the EAP.

In April 2023, the U.S. Food and Drug Administration (FDA) granted accelerated approval for tofersen. Following this approval, the EAP closed to new US participants. In May 2024, the European Medicines Agency granted marketing authorization of tofersen under exceptional circumstances. Access to new and ongoing patients will continue in countries in the European Union (EU) where local laws and regulations permit. As access to tofersen becomes available commercially in some EU countries, the EAP will close and people with SOD1-ALS can access tofersen through the local commercial channels. In countries outside of the US and EU, the EAP remains open to new and ongoing participants.

Treating HCPs can submit requests on behalf of people with SOD1-ALS who meet the inclusion/exclusion criteria by emailing

Friedreich’s ataxia (FA): Omaveloxolone (outside of U.S. only)

Only a qualified, licensed treating HCP may submit a request for early access to our investigational medical products. Please contact us at for information prior to submitting a request for early access. We will use our best efforts to acknowledge each submitted request within 2 business days. The request will be promptly evaluated after such acknowledgement in compliance with local laws and regulations. 

How to Submit a Request

All requests must be submitted by a licensed physician on behalf of the patient. All requests are considered in a fair and just manner in accordance with our guiding principles. However, please understand that submitting a request does not guarantee access will be granted.

Tofersen: Email

Aducanumab: Email

Our Early Access Guiding Principles

Biogen is equally committed to enacting early access to products in development for qualifying patients, and communicating with the patient community, healthcare providers (HCPs), and healthcare systems on the timing of such programs.

The following principles guide decisions to provide access to our programs:

  • Access for appropriate patient(s) to address high unmet medical need in a safe, ethical, and just manner in compliance with applicable laws and regulation.
  • Access while ensuring the integrity of clinical trials and the development of medicines.
  • Access that does not jeopardize the pathway to broad long-term access and approvals through local health systems.
  • Access that minimizes burden on healthcare systems, HCPs, patients, and families.

Medical Information

Healthcare providers, patients, and caregivers with a medical question can reach out to the Biogen Medical Information Team.

  • In the United States, please contact 1-866-MED-INFO, or
  • Outside of the United States, search for your country information here.

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