REVEAL Study: Phase 3 Study of the Efficacy and Safety of ION582 in Children and Adults with Angelman Syndrome

Condition studied

Angelman syndrome

Investigational medicinal product(s)

Eligibility

Primary endpoint

Change in performance on the Expressive Communication subdomain raw score of the Bayley Scales for Infant and Toddler Development-4 (Bayley-4) without caregiver input in Cohort 1 [Time Frame: Baseline and Week 52]

Endpoint detail

1. Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Cognition Subdomain Raw Score without caregiver input [Time Frame: Baseline and Week 52], 2. Change in Symptoms of Angelman Syndrome -Clinician Global Impression of Change (SAS-CGI-C): Overall AS [Time Frame: Baseline and Week 52], 3. Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Receptive Communication Subdomain Raw Score [Time Frame: Baseline and Week 52], 4. Change in Vineland Adaptive Behavior Scale-3 (Vineland-3): Daily Living Skills, Personal Subdomain Raw Score [Time Frame: Baseline and Week 52], 5. Change in Symptoms of Angelman Syndrome - Clinician Global Impression of Change (SAS-CGI-C): Sleep Problems [Time Frame: Baseline and Week 52], 6. Change in Bayley Scales for Infant and Toddler Development-4 (Bayley-4): Fine Motor Subdomain Raw Score without caregiver input [Time Frame: Baseline to Week 52], 7. Change in Observer-Reported Communication Ability (ORCA): Overall Emerging T score [Time Frame: Baseline and Week 52], 8. Percentage of Participants with Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs) [Time Frame: Up to Week 52], 9. Change in Vital Signs and Clinical Laboratory Results [Time Frame: Baseline and Week 52]