Fragile X Syndrome Clinical Trials
The EXPERIENCE Clinical Trials
Evaluation of Fragile X Experience in Cognition Expression
Update on EXPERIENCE-204 and EXPERIENCE-301
Enrollment for EXPERIENCE-204 and EXPERIENCE-301 is at capacity and screening is now closed. Shionogi is sincerely grateful to the families who participated in these studies as well as the clinical trial investigators and staff who have led the research. We look forward to sharing the results from these studies and remain committed to the EXPERIENCE clinical program, including through EXPERIENCE-302 (open-label study), which is ongoing for individuals who have completed EXPERIENCE-301 or 204.
What is Fragile X Syndrome?
FXS is the leading cause of inherited intellectual disabilities like autism spectrum disorder. FXS is known to have a greater effect on males than females because the mutation of the FMR1 gene is carried on the X chromosome. The most important clinical abnormality associated with FXS is global developmental delay and intellectual disability. The IQ of males with full mutation varies, with a mean value of 40–51. Other common symptoms of FXS include aggressiveness, attention problems and anxiety. FXS can cause challenges across many aspects of daily life, such as impacting individuals’ ability to care for themselves and communicate with others.
Select Study Eligibility Requirements
This is a subset of the full eligibility criteria. Additional eligibility criteria are discussed during screening visits.
Male with FXS and confirmed FMR1 gene mutation (≥ 200 CGG repetitions).
Participants must have a consistent caregiver who will attend all visits.
Currently receiving treatment with no more than three psychotropic medications (e.g., antidepressants, anti-anxiety medications, stimulants, antipsychotics, and mood stabilizers).*
Participants may continue with psychotropic medications*, behavioral/non-pharmacological treatments* and anti-epileptic medications† throughout the 13-week study.
EXPERIENCE-204: Adolescent Study in Fragile X Syndrome‡
(Also Known As BPN14770-CNS-204 or NCT05163808)
Males aged 9 to 17 with a genetic diagnosis of FXS.
Weigh at least 55 pounds and have a body mass index (BMI) less than or equal to 97 percent of their age group.
EXPERIENCE-301: Adult Study in Fragile X Syndrome‡
(Also Known As BPN14770-CNS-301 or NCT05358886)
We are no longer accepting screening appointments for the EXPERIENCE-301 clinical trial.
Males aged 18 to 45 with a genetic diagnosis of FXS.
Have a body mass index (BMI) between 18–36 kg/m2.
EXPERIENCE-302: Open-Label Extension Study in Fragile X Syndrome‡
(Also Known As BPN14770-CNS-302 or NCT05367960)
EXPERIENCE-302 (open-label study) is ongoing for individuals who have completed EXPERIENCE-204 or EXPERIENCE-301.
Up to four-year open-label extension for participants who complete the full 13 weeks of EXPERIENCE-204 or EXPERIENCE-301.
* Participants must be at a stable dose and dosing regimen for at least four weeks prior to screening. Dosing must remain stable throughout the 13-week study.
† Participants with a history of seizure, who are currently receiving treatment, must be seizure-free for three months prior to screening, or for two years if not on treatment.
‡ EXPERIENCE-204 and EXPERIENCE-301 are double-blind, which means that neither the participants nor the researchers know which treatment the participants are receiving. In both studies, participants are randomly selected to receive either zatolmilast (the investigational study drug) or placebo (a pill that does not include active drug) for 13 weeks. Approximately two of three participants will receive zatolmilast and one of three participants will receive placebo.