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Safety, Tolerability and Efficacy Study of STX209 in Subjects With Fragile X Syndrome

Phase 2
Completed
Conditions
Fragile X Syndrome
Interventions
Drug: Placebo
Registration Number
NCT00788073
Lead Sponsor
Seaside Therapeutics, Inc.
Brief Summary

The study objective is to explore the efficacy, safety and tolerability of STX209 for treatment of irritability in subjects with FSX. We hypothesize that STX209 will improve irritability and other typical problem behaviors associated with fragile X syndrome. We also hypothesize that STX209 will be safe and well tolerated.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
63
Inclusion Criteria
  • Male or female subjects 12 to 40 years of age eventually expanding to 6 years of age
  • Molecular documentation of the fragile X mutation.
  • Clinical Global Impression - Severity (CGI-S) rating for problem behavior of moderate or higher at screening and at Visit 1
  • An Aberrant Behavior Checklist (ABC-C) Irritability Subscale score >12 and at least 3 items on the Irritability Subscale rated at least moderate or above.
  • Current treatment with no more than three psychoactive medications, including anti-epileptics.
  • Current pharmacological treatment regimen has been stable for at least 4 weeks.
Exclusion Criteria
  • Subjects with a history of seizure disorder who are not currently receiving treatment with antiepileptics.
  • Subjects with any condition, including alcohol and drug abuse, which might interfere with the conduct of the study, confound interpretation of the study results, or endanger their own well-being. This includes, but is not limited to impairment of renal function, evidence or history of malignancy or any significant hematological, endocrine, cardiovascular, respiratory, hepatic, or gastrointestinal disease.
  • Subjects who plan to initiate or change pharmacologic or non-pharmacologic interventions during the course of the study.
  • Subjects who are currently receiving treatment with racemic baclofen.
  • Subjects currently treated with vigabatrin or tiagabine.
  • Subjects taking another investigational drug currently or within the last 30 days.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
STX209STX209STX209 variable dose from 1mg bid to 10mg tid, capsule, oral, 4 weeks
PlaceboPlacebovariable dose (same flexible dose titration protocol), bid to tid, capsule, Oral, 4 weeks
Primary Outcome Measures
NameTimeMethod
Aberrant Behavior Checklist Irritability SubscoreAfter 4 weeks of treatment

The Aberrant Behavior Checklist-Community Edition (ABC-C) is a 58-item questionnaire composed of five different independent subscales. The questionnaire is completed by the parent/caregiver and lists aberrant behaviors and asks about the severity of the problem. ABC-Irritability is one of the subscales and comprises of 15 items. Minimum score is 0, maximum is 45. A decreased score indicates few aberrant behaviors and clinical improvement. The entire ABC-C assessment is administered at baseline and then at the end of each Intervention Period (4 weeks after Baseline).

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (12)

Southwest Autism Research & Resource Center

🇺🇸

Phoenix, Arizona, United States

Riley Hospital for Children

🇺🇸

Indianapolis, Indiana, United States

M.I.N.D. Institute

🇺🇸

Sacramento, California, United States

Rush University Medical Center

🇺🇸

Chicago, Illinois, United States

Children's Hospital Boston

🇺🇸

Boston, Massachusetts, United States

NYS Institute for Basic Research in Developmental Disabilities

🇺🇸

Staten Island, New York, United States

University of North Carolina Neurosciences Hospital

🇺🇸

Chapel Hill, North Carolina, United States

Seattle Children's Hospital

🇺🇸

Seattle, Washington, United States

University of California-Los Angeles Neuropsychiatric Institute

🇺🇸

Los Angeles, California, United States

Suburban Research Associates

🇺🇸

Media, Pennsylvania, United States

Red Oaks Psychiatry Associates, P.A.

🇺🇸

Houston, Texas, United States

Vanderbilt Kennedy Center

🇺🇸

Nashville, Tennessee, United States

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