Fragile X Treatment Pipeline: Current and Emerging Clinical Trials
FRAXA hosted The Fragile X Treatment Pipeline: Current and Emerging Clinical Trials on June 10, 2026, to give families a practical look at research underway now and studies expected to begin soon.
The webinar came at an important time for the Fragile X community. Recent trial results have been difficult, but the overall treatment pipeline is very active.
The discussion featured clinicians Elizabeth M. Berry-Kravis, MD, PhD, Craig Erickson, MD, and FRAXA’s Mike Tranfaglia, MD. They reviewed current and emerging clinical trials, explained why eligibility criteria vary from study to study, and discussed how researchers are working to better measure meaningful change in Fragile X syndrome.
Key Takeaways from the Fragile X Clinical Trials Webinar
The main message from the webinar is that Fragile X research is moving forward with several clinical trial programs active now or expected to begin soon.
Approaches moving toward clinical trials include PDE4D inhibition, BK channel modulation, behavior-focused treatments, repurposed medications, and early genetic strategies.
Another major theme was measurement. Researchers are continuing to work on better ways to show whether a treatment is helping in ways that matter to families.
Clinical Trial Programs Discussed
The webinar covered several programs at different stages of development.
- Mirum PDE4D inhibitor trial
This Phase 2 trial of MRM-3379 is enrolling males ages 15 to 45 with Fragile X syndrome at sites across the United States. The investigational new drug targets PDE4D, the same pathway as zatolmilast. - Servier BK channel program
This program focuses on BK channel modulation, a strategy aimed at reducing neuronal hyperexcitability. A Phase 2 study of KER-0193 is expected to begin in adults in Europe and the United States. - Spinogenix SPG601
SPG601 is another BK channel modulator. Early single-dose testing showed encouraging changes in EEG and NIH Toolbox measures. A Phase 2b trial is expected to begin in the United States in late 2026 - SRX246 behavior-focused study
This study is focused on aggression, agitation, self-injury, and severe tantrums in adult males with Fragile X syndrome. SRX246 is a vasopressin 1a (V1a) receptor antagonist. Study visits are designed to take place in the home, supported by remote contact with study sites. - Pediatric repurposed medication study
This planned academic study will test single doses of ethosuximide and tacrine, two existing medications in children with Fragile X syndrome to look for early signs of brain or cognitive response. - QurAlis ASO/splicing strategy
This earlier-stage genetic strategy is focused on restoring FMRP production in individuals with Fragile X who produce a specific FMR1-related RNA. - CONNECTA trial in Spain
A Phase 2 study of CTH120, a first-in-class neuroplasticity modulator from CONNECTA, has begun in Spain, with trial sites in the Barcelona area.
Measuring Meaningful Change in Fragile X Trials
One of the challenges of Fragile X clinical research is measuring whether a treatment is helping in ways that matter to families.
Some studies use performance-based tools, such as cognitive testing or EEG. Others use caregiver-rated measures that ask families to track changes in language, daily function, behavior, or other areas of concern. Each approach has strengths and limits.
The webinar speakers discussed the need for better outcome measures that reflect real-life change. Reliable measures are essential to understand whether a treatment is having a real effect.
Additional Questions From the Community
Several families asked why trials may be limited to certain ages, males, or participants who can complete specific tests. The short answer is that trials are designed to answer a specific research question as clearly and safely as possible. Fragile X syndrome varies widely from person to person, and broader study groups can make results harder to interpret.
Some requirements are also tied to safety. Many trials require blood draws, medical monitoring, or the ability to swallow capsules. These requirements can be frustrating, but they are often required in early-stage drug studies.
Families also asked how to prepare for future trial opportunities. Helpful steps include keeping diagnostic records organized, maintaining an updated medication list, staying connected with Fragile X clinics or research centers, and monitoring trial listings as new studies open.
Resources and Next Steps
Families interested in Fragile X clinical trials can use ClinicalTrials.gov to review current trial listings, eligibility criteria, study locations, recruitment status, and contact information.
FRAXA also shares updates when new Fragile X clinical trials open or begin recruiting. Families can subscribe to FRAXA updates to receive future announcements.