Stay informed of our current clinical trials

Visit to learn about the current study of DNL151, known as BIIB122.

Register to stay updated on our clinical trails.

Why are clinical trials  important?

Clinical trials play an important part in the development of new potential treatments. There may be risk associated with clinical trials, and you should speak to your healthcare provider before participating. Participation in clinical trials may also have broad-reaching impacts that benefit the entire community:

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The safety and efficacy of possible new medications can be observed and documented

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New medications can be brought to market more quickly

Parkinson’s disease clinical trials help scientists connect the dots, increasing disease understanding

Long-term Impact

Contributing to medical research increases our disease understanding today and for future generations.

How do new drugs become available?

The federal Food and Drug Administration (FDA) regulates the process for bringing a new drug to market. The process seeks to protect participants as much as possible, while using documented scientific testing procedures to determine the new drug's benefit and risk profile. Here are the processes:

Icon: Phase 1 in the US FDA pathway

Participants: 20-100

Duration: Several months

Phase 1 seeks to generally understand the safe dosing schemes and potential side effects of an investigational drug. The study may be conducted in healthy volunteers or people with the disease.

Icon: Phase 2 in the US FDA pathway

Participants: Up to Several Hundred People Living with Disease

Duration: Several Months to 2 Years

Phase 2 identifies additional safety data and possible signs that an investigational drug may potentially be effective.

Icon: Phase 3 of the US FDA pathway

Participants: 300-3,000 People Living with Disease

Duration: 1-4 Years

Phase 3 seeks to demonstrate whether or not an investigational drug offers a treatment benefit to a specific population and provides a majority of the safety data. This phase typically supports the drug approval decision.

Participation in clinical trials is voluntary, and you may be interviewed or have baseline tests performed to determine if you are eligible for any specific study. You also have the right to withdraw at any time during the trial, for any reason. Talk to your healthcare provider about participating in clinical trials.


To find more information about Parkinson’s disease clinical trials, visit these sites:

DNL151 is an investigational drug and is not approved by any Health Authority

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