Spinal muscular atrophy guide to clinical trials

Last updated Aug. 6, 2025, by Agata Boxe
✅ Fact-checked by Ana de Barros, PhD

Although researchers have made progress developing therapies for spinal muscular atrophy (SMA), more work is needed to address disease progression and improve strength, mobility, and quality of life.

Scientists continue to explore new treatments through clinical trials, which assess whether new therapies are safe and effective before they are approved by the U.S. Food and Drug Administration (FDA).

Enrolling in an SMA clinical trial may give you or your child access to experimental treatments while helping to advance medical research. However, it is important that you consult your doctor or your loved one’s doctor as part of your decision-making process.

What is an SMA clinical trial?

A clinical trial is a carefully designed research study that tests new ways to treat, diagnose, and manage diseases, such as SMA, in people. While early-stage clinical trials typically follow laboratory and animal testing, later-stage trials build on findings from earlier human studies.

Clinical trials for SMA may focus on:

  • trying to improve muscle strength or motor function through medications
  • studying compounds that may help protect nerve cells from damage or death
  • studying new gene or mRNA-based therapies
  • assessing treatments for respiratory, nutritional, or orthopedic complications
  • testing new strategies to monitor disease progression or treatment response.

 

Clinical trials come in four separate phases:

  • Phase 1 trials test a treatment’s safety and determine appropriate dosages and regimens in a small number of participants.
  • Phase 2 trials continue to monitor safety and begin to evaluate how well the treatment works, often comparing it with a placebo or standard treatment in a larger group of patients.
  • Phase 3 trials are designed to confirm the safety and effectiveness of the new therapy against a placebo or an existing treatment, often involving even larger populations and treatment durations. These trials are usually conducted to support the therapy’s approval by regulatory entities.
  • Phase 4 trials are done after the therapy has received FDA approval to study its long-term effects and benefits in a real-world setting.

Weighing the benefits and risks of SMA trials

While the progressive nature of SMA and its severity may make someone more willing to join a clinical trial, it’s crucial to understand both the potential benefits and the risks.

The benefits of clinical trials include:

  • early access to new treatments
  • a chance to proactively manage your or your loved one’s SMA
  • an opportunity to contribute to research that may benefit others with SMA.

The risks of clinical trials can involve:

  • potential side effects from the new treatment
  • lack of improvement or worsening of symptoms
  • possibility of receiving a placebo or standard treatment
  • extra time for appointments, testing, or travel
  • costs not covered by insurance or the study sponsor.

Types of SMA clinical trials

Clinical trials for SMA can focus on various aspects of SMA care, ranging from testing new interventions that modify the disease course or improve quality of life to identifying new biomarkers that aid in monitoring disease progression and response to treatment.

Not all trials may be available or recruiting participants at any given time, but some examples of SMA trials that may be conducted include:

  • gene therapy or mRNA-based trials aimed at addressing the underlying genetic causes of SMA
  • treatments that aim to slow nerve cell loss
  • therapies that may help to preserve strength and improve mobility
  • trials targeting respiratory, nutritional, or bone problems
  • studies using imaging tests, biomarkers, or digital tools to track progression or response to treatment.

Some SMA trials are tailored to people with specific SMA types as well as different age groups or genetic profiles. They may also be available only to individuals who have never received treatment or who are no longer responding to approved SMA treatments.

Where to find SMA clinical trials

To find an SMA clinical trial, start by talking to your or your child’s SMA doctor, who may know of trials through academic hospitals, research centers, or clinical trial networks. They can also help evaluate whether you or your child may be eligible for a trial.

Additionally, you can consult online resources for more information. Resources that may help you find a suitable SMA trial in the United States include:

SMA trial registries outside the United States include:

What to ask before joining an SMA clinical trial

If you’re considering participating in an SMA clinical trial, asking the right questions can help you make an informed decision. It may be helpful to put together a list of questions for your SMA doctor, the research team, and even yourself as you learn more about the trial process.

Questions for your SMA doctor

Your doctor can answer general questions about SMA trials, such as:

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

Questions for the research team

The research team running the trial can address more detailed questions about its design and potential side effects.

Examples of questions for the researchers include:

  • What kind of treatment will the trial be testing, and why do you think it will work?
  • Are there any known side effects, and if so, how can they be managed?
  • Does this study involve a placebo or another SMA treatment that is already on the market?
  • What are the odds of receiving a placebo or another SMA treatment versus the new treatment?
  • Who will cover the costs of my participation in the trial, and do I need insurance?

Inquiring about potential costs is especially important. Although most trials tend to 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, ask your insurer whether they can pay for your participation in the study and care for potential side effects.

Questions to ask yourself

Personal reflection can help you decide whether a trial might be right for you. Questions to ask yourself include:

  • How do I hope to benefit 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 affect my daily life?
  • Am I willing to accept the time commitment and potential travel and expenses related to the trial?
  • Can I manage the emotional impact if the new treatment doesn’t work for me?

Additional information about SMA clinical trials

SMA clinical trials can provide a chance to try experimental treatments and play an active role in your or your child’s SMA care. However, keep in mind that they’re not for everyone, so it’s important to understand their risks and benefits.

Remember to talk to your SMA doctor first, so they can help you decide whether an SMA trial is right for you. Don’t hesitate to ask questions and advocate for yourself as you make this and other key decisions about your health and future.

SMA 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.

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