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Placebo-Controlled, Single-Dose Challenge Study of Gaboxadol in Adult Males With Fragile X Syndrome (FXS)

Phase 2
Recruiting
Conditions
Fragile X Syndrome
Interventions
Drug: Placebo
Registration Number
NCT06334419
Lead Sponsor
Craig Erickson
Brief Summary

This is a single dose, placebo-controlled study. Male subjects aged 18 to 40 years (inclusive) with a diagnosis of FXS. Eligible subjects may enroll in this study comprised of two in home and two in clinic visits each 14 days apart, for a total of four visits. Subjects will be given single dose gaboxadol (10 mg) or matched placebo at each of these visits to take orally. Thus, all enrolled subjects will receive placebo at home and in clinic and receive gaboxadol at home and in clinic in a blinded fashion.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
Male
Target Recruitment
10
Inclusion Criteria
  1. Subject consents to participate, or if they are not their own legal guardian, offers assent supported by legally authorized representative consent
  2. Subject is willing and able to comply with the study procedures as specified in the protocol and to comply with the study drug administration. Caregiver also commits to the study requirements prior to any study-related procedures
  3. Subject and caregiver are both able to understand the spoken national language clearly and caregiver can read and write to complete study assessments
  4. Males age 18 to 40 years (inclusive)
  5. Has FXS with molecular genetic confirmation of the full FMR1 mutation (>200 cysteine-guanine-guanine [CGG] repeats). May have been confirmed historically or at Screening
  6. Is in general good health as deemed by the Investigator, determined by physical examination, medical history, and laboratory tests
  7. If receiving serotonin-selective reuptake inhibitor (SSRI), serotonin-norepinephrine reuptake inhibitor (SNRI), or serotonin antagonist and reuptake inhibitor (SARI), is on a stable, well-tolerated dose for the previous 3 months with no further changes anticipated
  8. Is not sexually active or can confirm at least one form of contraceptive
Exclusion Criteria
  1. Any chronic major medical comorbid condition deemed by the Investigator as presenting added risk to the subject, including but not limited to, refractory hypertension, kidney disease, or liver disease
  2. Diagnosed with diabetes (Type 1 or II) or receiving any anti-diabetic medication
  3. Unstable seizure disorder, defined by any seizure within 6 months prior to baseline visit and/or a change in any anti-convulsant drug dosing in the 60 days prior to study consent
  4. Changes in psychotropic or anti-convulsant (where taken for reasons other than seizure control) drug treatment within 30 days prior to Screening
  5. Significant changes in any educational, behavioral, and/or dietary interventions the month prior to Screening
  6. Planned initiation of new, or modification of ongoing, interventions during the study
  7. Unable or unwilling to take oral medication (whole capsule, despite assistance with a spoonful of applesauce, yoghurt, or equivalent liquid food)
  8. Consumption of liver enzyme inducers or inhibitors including and not limited to foods, medicines, herbal remedies and supplements three days prior to any Visit. Foods or beverages containing CYP3A4/5 inhibitors (e.g., grapefruit, pomegranate, pomelo, and star fruit) should be avoided before taking study medication and for up to 1 hour post dose throughout the study
  9. Has abnormal baseline laboratory assessments including, but not limited to, alanine aminotransferase (ALT) or aspartate aminotransferase (AST) or total bilirubin >1.5 × the upper limit of normal (ULN), serum creatinine >1.5 x ULN or other clinically relevant laboratory abnormality
  10. Has a clinically significant heart rate or blood pressure (BP) at Screening as judged by the Investigator
  11. Has received an investigational drug in any prior clinical study within 30 days or 5 half-lives (whichever is longer) prior to Screening

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
All Study ParticipantsPlaceboParticipants received, in random order, a single dose of placebo or Gaboxadol with a two-week washout period between doses. The gaboxadol dosage selected for this study is 10 mg or Placebo as a single dose on each study visit (two at home and two in clinic).
All Study ParticipantsGaboxadolParticipants received, in random order, a single dose of placebo or Gaboxadol with a two-week washout period between doses. The gaboxadol dosage selected for this study is 10 mg or Placebo as a single dose on each study visit (two at home and two in clinic).
Primary Outcome Measures
NameTimeMethod
To evaluate target engagement of gaboxadol treatment on high density EEG recordingsPre-dose, 60 minutes post-dose

Changes in EEG recordings with gaboxadol treatment (60-90 minutes post-dose compared with pre-dose on resting theta, alpha and gamma band relative and absolute power; brain response to auditory chirp stimuli in the gamma band range).

Secondary Outcome Measures
NameTimeMethod
To investigate the feasibility of high density EEG recording at home in adult males with FXSPre-dose, 60 minutes post-dose

Quality of EEG recordings in the home setting compared with EEG recordings performed in the hospital setting. We will compare the duration of usable artifact free EEG resting data from the same subject gathered at home and at clinic.

To investigate the effect of gaboxadol treatment on eye tracking assessmentsPre-dose, 60 minutes post-dose

Change in eye tracking outcomes (60-90 minutes post-dose compared to pre-dose on percent viewing of social versus geometric scene

To determine whether FMRP levels predict treatment responsePre-dose and post-dose

Relationship between FMRP (Fragile X messenger ribonucleoprotein) level and degree of change (baseline/screen to post-dose) across measures

To investigate the effect of gaboxadol treatment on clinician-rated measuresPre-dose and post-dose

Change in clinician-rates measures (post-dose compared to pre-dose on CGI-I)

To potentially explore the pharmacokinetics of gaboxadol treatment in single-dose trial designPre-dose, 60 minutes post-dose

PK profile (the level of gaboxadol in human plasma) will be obtained at 60 +/- 10 minutes post-dose only).

To investigate the feasibility of home research visits and procedures in adult males with FXSPre-dose, 60 minutes post-dose

Quality and test-retest reliability of assessments performed at home compared with the hospital setting. This includes blood testing for Fragile X messenger ribonucleoprotein (FMRP: range of 0-40 picomolar) and eye-tracking of eye gaze to eye regions when viewing faces (range of value from 0 percent to 100 percent; higher values are associated with a neurotypical phenotype).

To investigate the effect of gaboxadol treatment on neuropsychological assessmentsPre-dose, 60 minutes post-dose

Changes in cognitive and neuropsychological assessment measures with gaboxadol treatment (RBANS). RBANS list learning subscale score range is -4 to +4, higher values are indicative of greater memory.

Trial Locations

Locations (1)

Cincinnati Children's Hospital Medical Center

🇺🇸

Cincinnati, Ohio, United States

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