New Treatments & Clinical Trials for Spinal Muscular Atrophy

Spinal muscular atrophy is a genetic disease that weakens muscles throughout the body. It's caused by low levels of the SMN protein, which motor neurons need to survive. Three approved therapies — nusinersen, onasemnogene abeparvovec, and risdiplam — now change the course of SMA, especially when started early. Most trials today focus on improving what these drugs can do.

What's actually going on in research

Trials are testing combination approaches that pair existing SMN-restoring drugs with muscle-building treatments, neuroprotective agents, or gene therapy refinements. Researchers are also studying physical therapy protocols tailored to SMA, assistive technology for daily function, and biomarkers that predict how well someone will respond to treatment. Some work explores late-onset SMA, where treatment patterns are less clear.

What to know before you search

Eligibility typically depends on SMA type, age at symptom onset, current motor function, whether you've received prior SMN-restoring therapy, and genetic confirmation of SMN1 deletion or mutation.

What types of trials are currently open

• Drug combination trials — Testing whether adding a muscle-building drug to nusinersen, risdiplam, or gene therapy produces better strength gains than SMN therapy alone.
• Gene therapy trials — Studying refined or second-generation gene therapies, sometimes for people who didn't receive the first-approved version or who have later-onset SMA.
• Rehabilitation trials — Testing specific physical therapy programs or assistive devices to see what safely improves mobility and daily function in people on SMN-restoring treatment.
• Natural history studies — Following people with SMA over time to understand how the disease progresses with and without treatment, and what factors predict outcomes.
• Biomarker studies — Measuring proteins or other markers in blood or spinal fluid to predict treatment response and track disease activity.