Multiple sclerosis guide to clinical trials

Last updated Aug. 6, 2025, by Agata Boxe
Fact-checked by Inês Martins, PhD

Clinical trials play a crucial role in the development, testing, and approval of new therapies for multiple sclerosis (MS). For people living with MS, they can offer a way to try experimental treatments that aren’t yet available to the public while also contributing to research that could help others in the future.

Understanding how clinical trials work — and what participation involves — can help you make an informed choice about whether one might be right for you.

What’s a clinical trial?

A clinical trial is a research study that examines new treatment approaches in people to see if they’re safe and effective before they can be potentially approved by the U.S. Food and Drug Administration (FDA). This process usually follows preclinical studies in animals.

Trials are essential for advancing MS treatments, from disease-modifying therapies (DMTs) to symptom-relief options. Aside from testing new medications, trials can also look at other approaches that may improve MS management and diagnosis.

MS clinical trials come in four different phases:

• Phase 1 trials examine a treatment’s safety, determine appropriate dose ranges and regimens, and identify potential side effects in a small group of people.
• Phase 2 trials, which can last from months to years, further assess safety while beginning to evaluate how well the treatment works in a larger group of participants, often by comparing the new therapy with a standard treatment or placebo.
• Phase 3 trials involve an even larger population, typically ranging from a few hundred to thousands of patients, and compare the new treatment with existing therapies or a placebo to confirm its effectiveness, monitor side effects, and collect data to support regulatory approval.
• Phase 4 trials are post-marketing studies conducted after FDA approval, which gather data on the therapy’s long-term safety and effectiveness in real-world settings.

In addition to these phases, pilot trials may also be conducted early on to explore the feasibility of a new intervention, refine study design, or gather preliminary safety and efficacy data before launching larger trials.

The benefits and risks of clinical trials

Before participating in an MS trial, it is essential to consider both the advantages and potential risks involved.

The benefits of clinical trials for MS include:

• getting access to a new treatment that may work for you
• taking a proactive role in managing your health
• helping to advance MS research and find new treatments.

Risks of clinical trials and other issues include:

• experiencing potential side effects
• facing disappointment if the new treatment doesn’t work for you
• having to dedicate time to potential extra tests and doctor visits
• dealing with the possibility of receiving a placebo instead of an active treatment
• managing potential costs that may not be covered by insurance.

What types of MS trials are available

MS trials can focus on different aspects of the disease, ranging from slowing disease progression to addressing symptoms such as fatigue and spasticity (muscle tightness and spasms). People with MS can participate in several types of trials, which examine medications to manage the disease, as well as lifestyle interventions and novel diagnostic techniques.

Although not all trials will be ongoing at any given time, some examples of MS trials that may be conducted include:

• DMT trials, which test new medications that aim to slow disease progression or reduce the frequency of relapses
• symptom management trials, which explore treatments for MS fatigue, walking difficulties, chronic pain, and other MS symptoms
• lifestyle and rehabilitation trials, which examine the impact of interventions such as exercise programs, specific diets, and physical therapy on certain symptoms and quality of life
• diagnostic trials, which evaluate new tools or technologies to better detect or monitor MS and its progression
• biomarker or imaging studies, which collect blood, spinal fluid, or imaging data to identify potential signs of disease activity or track response to treatment.

Trials may focus on specific MS types and may recruit groups of patients based on age, sex, or disease duration. They may also specify that they are for newly diagnosed patients, who have not received any MS treatment, or for those who have failed specific DMTs.

Where to find information about MS clinical trials

You can find out more about clinical trials for MS by consulting your doctor and reviewing relevant resources. Many of them provide listings of ongoing MS studies, including eligibility criteria and locations.

First, ask your MS doctor, who may be aware of specific trials through hospitals, universities, or research networks and will be able to recommend a trial that’s right for you.

Other sources include:

• clinicaltrials.gov
• the National MS Society
• the Multiple Sclerosis Association of America
• CenterWatch.

Trial opportunities outside the United States include:

• EU Clinical Trials Register
• the U.K.’s ISRCTN Registry
• MS Society UK
• MS Australia.

Regardless of the research you may do on your own, talking to your MS doctor first is vital. Only they can determine whether you may be a good candidate for a trial, and if so, what type of trial.

They can also assess how your potential participation may affect your symptoms and current treatment plan and help to navigate these and other issues.

Asking the right questions

Asking questions can help you make a decision about potential trial participation. It is important to know exactly what to ask your MS doctor, the research team, and yourself as you are exploring the process.

Questions to ask your doctor:

• Am I a good candidate for an MS clinical trial?
• Are you aware of any clinical trials for MS that would be suitable for my disease type and symptoms?
• Would participating in a clinical trial affect my current treatment plan?
• What are the potential risks and benefits of the clinical trial you may be recommending?
• What would the trial involve regarding treatment, travel, and time commitment?

Questions to ask the research team:

• What kind of treatment will the trial be testing, and why do you think it will work?
• What are the potential side effects, and will I receive adequate support if I experience them?
• Does this study involve a placebo or another MS treatment that is already on the market?
• What are the chances of my receiving a placebo or another MS treatment versus the new treatment being studied?
• Who will cover the costs of my participation in the trial, and do I need insurance?

Inquiring about potential costs is especially important. While most trials cover the costs of experimental treatment and any related medical care, that may not be the case for every single study.

If you are currently insured, also ask your insurer whether they can pay for your participation in the study and care for any potential side effects.

Finally, personal reflection can help you determine whether a trial might be right for you. Questions to ask yourself include:

• What do I hope to gain from the trial, and are my expectations realistic?
• Am I willing to accept the risks, such as potential side effects or a chance of receiving a placebo?
• How may this trial impact my daily life?
• Can I manage the time commitment and potential travel and expenses related to the trial?
• Am I ready to handle the emotional impact if the new treatment doesn’t work for me?

Other considerations

Joining an MS clinical trial can give you access to new therapies that aren’t yet widely available. Still, it is a personal decision that you should consider carefully, with full awareness of the potential risks and benefits.

Trials may not be right for everyone, but they do play a crucial role in advancing MS research and could be helpful in managing the disease.

If you think you may be interested in a trial, talk to your doctor. They can guide you through the process and help you find a study that is appropriate for your MS type, symptoms, and other individual characteristics.

Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.