Natural History Study in Pediatric Patients With STXBP1 Encephalopathy With Epilepsy

A Phase 0 Non-interventional, Multi-center, Natural History Study in Pediatric Patients With Syntaxin Binding Protein 1 (STXBP1) Encephalopathy With Epilepsy

This is a prospective, non-interventional, longitudinal study designed to characterize the natural history of STXBP1 related encephalopathy with epilepsy, in participants ≤ <5 years of age.

Study Overview

• Status: Not yet recruiting
• Conditions: STXBP1 Encephalopathy With Epilepsy

• Study Type: Observational
• Enrollment (Anticipated): 20

Contacts and Locations

• Study Contact: Name: Medical Monitor; Email: clinicaltrials@capsida.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 1 year to 3 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

≤5 years of age with STXBP1 related encephalopathy with epilepsy.

Description

Inclusion Criteria:

• Male or female, > 1 day to ≤ 5 years of age at the time of informed consent.
• Diagnosed with seizure disorder
• Presence of a STXBP1 gene mutation. Historical documentation is sufficient to support eligibility for the study. Confirmatory testing will be obtained at baseline and performed by a CLIA certified laboratory
• Written informed consent provided by a parent or legal guardian

Exclusion Criteria:

• History of prior gene therapy treatment
• Current enrollment in an interventional study or has received an investigational drug within 30 days or fewer than 5 half-lives prior to screening visit, whichever is longer
• Treatment with any antisense oligonucleotide therapy within 6 months prior to screening and anticipate remaining on treatment throughout the study
• The presence of a confirmed mutation in a gene other than STXPB1 that is known to contribute to a neurodevelopmental disability
• Presence of a significant non-STXBP1 related central nervous impairment/behavioral disturbance that would confound the scientific rigor or interpretation of results of the study
• History of prematurity (defined as gestational age <35 weeks), interventricular hemorrhage, structural brain deficit or congenital heart disease
• Requires mechanical ventilation or non-invasive respiratory support such as continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) at the time of informed consent

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in neurodevelopmental parameters of adaptive behavior function over time utilizing the Vineland Adaptive Behavior Scales-II (VABS-II) Age-equivalent Scores	The Vineland Adaptive Behavior Scales, Second Edition (Survey Interview Form) is a measure of adaptive behavior in children, adolescents and adults. It yields an overall standard score (Adaptive Behavior Composite, ABC) and age standard scores in four domains. ABC scores have a mean of 100 and a standard deviation of 15 (range = 20 to 160). Higher scores suggest a higher level of adaptive functioning.	2 Years
Changes in neurodevelopment parameters over time utilizing an age appropriate assessment.	The determination of whether a patient received Bayley Scales of Infant Development-III (BSID-III) is based on an algorithm that includes the patient's calendar age and VABS-II age-equivalent score (See Outcome 1). The BSID-III is a series of measurements to assess the motor (fine and gross), language (receptive and expressive), and cognitive development of infants and toddlers and consists of a series of developmental play tasks. contains two scoring systems of composite scores and percentile ranks. The normal range for composite scores is between 40-160 with mean at 100 and 0-99 for the percentile ranks. Higher scores mean a better outcome.	2 Years
Changes in neurodevelopment parameters over time utilizing an age appropriate assessment.	The determination of whether a patient received Kaufman Assessment Battery for Children-II (KABC-II) is based on an algorithm that includes the patient's calendar age and VABS-II age-equivalent score (See Outcome 1). The KABC-II is an individually administered measure of processing and reasoning abilities. The scoring range is 69 and below through 131 or greater. Higher scores mean a better outcome.	2 Years
Changes in seizure frequency over time	Seizure diary	2 Years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in communication ability over time	Observer-Reported Communication Ability (ORCA) Outcome Measure. The ORCA measure produces a single score that is an estimate of an individual's overall level of communication ability. Higher ORCA scores reflect greater communication ability; the mastery of expressive, receptive, and pragmatic types of communication and higher vocabularies for verbal words and symbols on assistive devices. The ORCA T-score range is from 26.82 to 83.24.	2 Years
Changes in sleep behavior over time	Patient sleep habits will be assessed using Children's Sleep Habits Questionnaires (CSHQ).	2 Years
Changes in electroencephalogram (EEG) recording over time	Standard EEG, lasting approximately 1 hour, to assess the presence of epileptiform activity.	2 Years
Changes in motor function over time utilizing an age appropriate assessment.	The Hammersmith Infant Neurological Examination (HINE) is aimed to be used for infants between 3 and 24 months of age and assess different aspects of neurological function: cranial nerve function, movements, reflexes and protective reactions and behavior, as well as some age-dependent items that reflect the development of gross and fine motor function. Each item is scored 0-3, higher scores mean a better outcome.	2 Years
Changes in motor function over time utilizing an age appropriate assessment.	The Gross Motor Function Measure-88 is aimed to be used for children 5 months or older of age and assess changes in gross motor function over time. Each item is scored 0-3, higher scores mean a better outcome.	2 Years

Collaborators and Investigators

• Sponsor: Capsida Biotherapeutics, Inc.
• Investigators: Study Director: Medical Monitor, MD, Capsida Biotherapeutics, Inc.

Study record dates

Study Major Dates

• Study Start (Anticipated): July 1, 2023
• Primary Completion (Anticipated): January 1, 2026
• Study Completion (Anticipated): January 1, 2026

Study Registration Dates

• First Submitted: July 5, 2022
• First Submitted That Met QC Criteria: July 13, 2022
• First Posted (Actual): July 18, 2022

Study Record Updates

• Last Update Posted (Actual): October 18, 2022
• Last Update Submitted That Met QC Criteria: October 14, 2022
• Last Verified: October 1, 2022

More Information

Terms related to this study

• Keywords: Epilepsy; Genetic Diseases, Inborn; Seizures; STXBP1; Epileptic encephalopathy
• Additional Relevant MeSH Terms: Central Nervous System Diseases; Nervous System Diseases; Epilepsy, Generalized; Epileptic Syndromes; Epilepsy; Brain Diseases; Spasms, Infantile
• Other Study ID Numbers: CAP-002-501

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No