A Phase 2 interventional study of Basmisanil and Placebo in Dup15Q Syndrome, sponsored by Newleos Therapeutics, Inc.. Not yet recruiting at 1 site in United States. Open to participants aged 2 Years to 14 Years. Per ClinicalTrials.gov, last updated 2026-09-29.
Sponsored by Newleos Therapeutics, Inc. · Phase 2, Interventional, and Treatment
The primary goal of this Phase 2 clinical trial is to determine the effects of a selective negative allosteric modulator (NAM) of GABAA α5 receptor, Basmisanil (NTX-1511), on brain wave (EEG) characteristics in children and adolescents with Dup15q syndrome. The main questions this trial aims to answer are:
Researchers will compare the effects of NTX-1511 with matching placebo (look-alike granules that contain no drug).
Participants will:
Newleos Therapeutics, Inc. is the lead sponsor of 3 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Drug: Basmisanil
Drug: Placebo
Three times daily (TID) x 12 weeks
Three times daily (TID) x 12 weeks
Change in quantitative electroencephalogram (qEEG) beta-band power
Time frame: Baseline to Week 12
Change in Dup15q Clinical global impression of severity (CGI-s) and change (CGI-C)
The Dup15q Syndrome Clinician Global Impression of Severity (Dup15q CGI-S) is a clinician-rated measure of global severity of illness at a given point in time. Each domain scoreranges from 1-6. Higher scores indicate higher severity of illness. The Dup15q Syndrome Clinician Global Impression of Change (Dup15q CGI-C) is a clinician-rated measure assessing the clinician's impression of change in illness compared with baseline. Each domain score ranges from 1-7. Lower scores indicate improved symptoms, and higher scores indicate worsening symptoms.
Time frame: Baseline to Week 12
Change in Vineland Adaptive Behavior Scales -Third Edition (Vineland-3) subdomain Growth Scale Value (GSV) scores
The Vineland Adaptive Behavior Scales -Third Edition (Vineland-3) measures adaptive behavior in 3 domains: Communication (subdomains Expressive, Reception, and Written), Socialization (subdomains Interpersonal, Play \& Leisure, Coping Skills), and Daily Living Skills (Personal, Domestic, Community), and also yields an overall Adaptive Behavior Composite score. The domains and the Composite are reported as a standard score (population mean 100; standard deviation 15; range 20-140). The subdomains are reported as v-scale scores (population mean 10, standard deviation 3; range 1-24). Higher scores indicate higher adaptive behavior abilities
Time frame: Baseline to Week 12
Change in Behavior Assessment System for Children - Third Edition (BASC-3) composite and scale scores
The Behavior Assessment System for Children (BASC-3) assesses behavioral and emotional concerns. It has multiple scales: Externalizing Problems (subscales Hyperactivity, Aggression; Conduct Problems); Internalizing Problems (Anxiety, Depression Somatization); additional subscales of Attention Problems, Atypicality, and Withdrawal, and an overall Behavioral Symptoms Index. Each of these scales and subscales is scored as a T-score (population mean of 50, standard deviation of 10; range 20-120). Higher T-scores indicate greater behavioral challenges.
Time frame: Baseline to Week 12
Change in Aberrant Behavior Checklist - Second Edition Community Version (ABC-2-C) domain scores
The Aberrant Behavior Checklist (ABC-2-C) domain scores assess challenging behaviors. The domain scores each have different ranges: Irritability from 0-45; Lethargy/Social Withdrawal 0-48; Stereotypy 0-21; Hyperactivity 0-48; Inappropriate Speech 0-12. Higher scores indicate more severe symptoms.
Time frame: Baseline to Week 12
Incidence and severity of adverse events (AEs) and severe AEs (SAEs)
Time frame: Baseline to Week 12
Incidence of treatment discontinuations due to Adverse Events
Time frame: Baseline to Week 12
Incidence of abnormalities in vital signs, electrocardiograms (ECGs) (PR, QRS, and QT intervals, as well as any other dysrhythmias or abnormal wave), laboratory results (chemistry, hematology and urinalysis), and/or physical examination
Time frame: Baseline to Week 12
Change from baseline in frequency, duration, and type of any seizures as reported in a seizure diary by caregivers
Time frame: Baseline to Week 12
Treatment-emergent abnormal changes in electroencephalograms
For this safety assessment, electroencephalograms (EEGs) will undergo a typical clinical interpretation by a qualified pediatric epileptologist. Any and all treatment-emergent changes will be recorded.
Time frame: Baseline to Week 12
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Newleos Therapeutics, Inc.