Efficacy and Safety Study of STX209 (Arbaclofen) for the Treatment of Social Withdrawal in Children With Fragile X Syndrome (Harbor-C)

A Randomized, Double-Blind, Placebo-Controlled, Fixed-Dose Study of the Efficacy, Safety, and Tolerability of STX209 (Arbaclofen) Administered for the Treatment of Social Function in Children With Fragile X Syndrome

There will be four study periods: Screening (up to 14 days in length), the Treatment Period (8 weeks), the Withdrawal Period (22 days), and Follow-up Period (up to 31 days). Subjects will be randomized to receive either STX209 (5 mg twice daily [BID], 10 mg BID or 10 mg three times daily [TID]) or placebo. Efficacy,safety and tolerability assessments will be performed periodically

Study Overview

• Status: Completed
• Conditions: Fragile X Syndrome
• Intervention / Treatment: Drug: arbaclofen; Drug: arbaclofen; Drug: arbaclofen; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 172
• Phase: Phase 3

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Phoenix, Arizona, United States, 85006
      • Southwest Autism Research & Resource Center
  • California
    • Long Beach, California, United States, 90806
      • Miller Children's Hospital
    • Sacramento, California, United States, 95817
      • University of California-Davis, M.I.N.D. Institute
    • San Diego, California, United States, 92108
      • Psychiatric Centers at San Diego
  • Colorado
    • Aurora, Colorado, United States, 80045
      • University of Colorado Denver, Children's Hospital
  • Florida
    • Miami, Florida, United States, 33136
      • University of Miami, Mailman Center for Child Development
    • Orange City, Florida, United States, 32763
      • Lake Mary Pediatrics
  • Georgia
    • Decatur, Georgia, United States, 30033
      • Emory University School of Medicine
  • Illinois
    • Chicago, Illinois, United States, 60612
      • Rush University Medical Center
  • Kansas
    • Fairway, Kansas, United States, 66205
      • Kansas University Clinical Research Center
  • Maryland
    • Baltimore, Maryland, United States, 21205
      • Kennedy Krieger Institute
  • Massachusetts
    • Worcester, Massachusetts, United States, 01605
      • University of Massachusetts
  • Michigan
    • Detriot, Michigan, United States, 48201
      • Children's Hospital of Michigan
  • Missouri
    • Columbia, Missouri, United States, 65211
      • University of Missouri, Thompson Research Center for Autism & Neurodevelopmental Disorders
  • New York
    • New York, New York, United States, 10029
      • Seaver Autism Center, Mount Sinai Medical Center
    • Staten Island, New York, United States, 10314
      • New York State Institute for Basic Research in Developmental Disabilities
  • North Carolina
    • Durham, North Carolina, United States, 27710
      • Duke Clinical Research Unit
  • Ohio
    • Akron, Ohio, United States, 44308
      • Akron Children's Hospital
    • Cincinnati, Ohio, United States, 45229
      • Cincinnati Children's Hospital
  • Oklahoma
    • Oklahoma City, Oklahoma, United States, 73117
      • University of Oklahoma, Physician's Child Study Center
  • Pennsylvania
    • Media, Pennsylvania, United States, 19063
      • Suburban Research Associates/Elwyn Genetics
  • South Carolina
    • Greenwood, South Carolina, United States, 29646
      • Greenwood Genetics Center
  • Tennessee
    • Nashville, Tennessee, United States, 37203
      • Vanderbilt Kennedy Center
  • Texas
    • Dallas, Texas, United States, 75235
      • Childrens Medical Center Dallas
    • Houston, Texas, United States, 77030
      • Texas Children's Hospital
    • Houston, Texas, United States, 77090
      • Red Oaks Psychiatry Associates, P.A.
    • San Antonio, Texas, United States, 78258
      • Road Runner Research
  • Washington
    • Seattle, Washington, United States, 98101
      • Seattle Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 5 years to 11 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Molecular documentation of the full FMR1 mutation
• Current pharmacological treatment regimen has been stable for at least 4 weeks prior to Screening.
• Subjects with a history of seizure disorder must currently be receiving treatment with antiepileptics and must have been seizure free for 6 months, or must be seizure free for 3 years if not currently receiving antiepileptics.
• If the subject is already receiving stable non-pharmacologic educational, behavioral, and/or dietary interventions, participation in these programs must have been continuous during the 2 months prior to Screening

Exclusion Criteria:

• 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.
• Subjects who plan to initiate or change pharmacologic or non-pharmacologic interventions during the course of the study.
• Subjects who have taken another investigational drug within the last 30 days.
• Subjects who are not able to take oral medications

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo	Drug: Placebo; tid
Active Comparator: STX209 5 mg BID	Drug: arbaclofen; 5 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg tid; Other Names: R-baclofen, STX209
Active Comparator: STX209 10 mg BID	Drug: arbaclofen; 5 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg tid; Other Names: R-baclofen, STX209
Active Comparator: STX209 10 mg TID	Drug: arbaclofen; 5 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg bid; Other Names: R-baclofen, STX209; Drug: arbaclofen; 10 mg tid; Other Names: R-baclofen, STX209

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Aberrant Behavior Checklist-Lethargy Social Withdrawal subscale	This is a single subscale of the aberrant behavior checklist entitiled Lethargy Social Withdrawal	at 8 weeks of treatment

Collaborators and Investigators

• Sponsor: Seaside Therapeutics, Inc.

Study record dates

Study Major Dates

• Study Start: June 1, 2011
• Primary Completion (Actual): June 1, 2013

Study Registration Dates

• First Submitted: March 28, 2011
• First Submitted That Met QC Criteria: March 28, 2011
• First Posted (Estimate): March 29, 2011

Study Record Updates

• Last Update Posted (Estimate): July 31, 2013
• Last Update Submitted That Met QC Criteria: July 30, 2013
• Last Verified: July 1, 2013

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Disease; Congenital Abnormalities; Genetic Diseases, Inborn; Genetic Diseases, X-Linked; Mental Retardation, X-Linked; Intellectual Disability; Heredodegenerative Disorders, Nervous System; Chromosome Disorders; Sex Chromosome Disorders; Syndrome; Fragile X Syndrome; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; GABA Agents; Neuromuscular Agents; Muscle Relaxants, Central; GABA Agonists; GABA-B Receptor Agonists; Baclofen
• Other Study ID Numbers: 209FX302