A randomized, double-blind, placebo-controlled phase II trial to explore the effects of a GABA-α5 NAM (basmisanil) on intellectual disability associated with Down syndrome.

Background: There are currently no pharmacological therapies to address the intellectual disability associated with Down syndrome. Excitatory/inhibitory imbalance has been hypothesized to contribute to impairments in cognitive functioning in Down syndrome. Negative modulation of the GABA-α5 receptor is proposed as a mechanism to attenuate GABAergic function and restore the excitatory/inhibitory balance.

The STARS Phase 2 Study: A Randomized Controlled Trial of Gaboxadol in Angelman Syndrome.

Objective: To evaluate safety and tolerability and exploratory efficacy end points for gaboxadol (OV101) compared with placebo in individuals with Angelman syndrome (AS).

Methods: Gaboxadol is a highly selective orthosteric agonist that activates δ-subunit-containing extrasynaptic γ-aminobutyric acid type A (GABA) receptors. In a multicenter, double-blind, placebo-controlled, parallel-group trial, adolescent and adult individuals with a molecular diagnosis of AS were randomized (1:1:1) to 1 of 3 dosing regimens for a duration of 12 weeks: placebo morning dose and gaboxadol 15 mg evening dose (qd), gaboxadol 10 mg morning dose and 15 mg evening dose (bid), or placebo morning and evening dose.

Adaptive behavior in adolescents and adults with Down syndrome: Results from a 6-month longitudinal study.

Measures of adaptive behavior are important in the assessment and treatment of individuals with intellectual disabilities (ID). The purpose of the current study was to evaluate the stability of an established and a novel measure of adaptive behavior over time, and their suitability as outcome measures in clinical trials targeting individuals with Down syndrome (DS). This 6-month, longitudinal, noninterventional, multinational study included adolescents (12-17 years) and adults (18-30 years) with DS.

Clinical Development of Targeted Fragile X Syndrome Treatments: An Industry Perspective.

Fragile X syndrome (FXS) is the leading known cause of inherited intellectual disability and autism spectrum disorder. It is caused by a mutation of the fragile X mental retardation 1 () gene, resulting in a deficit of fragile X mental retardation protein (FMRP). The clinical presentation of FXS is variable, and is typically associated with developmental delays, intellectual disability, a wide range of behavioral issues, and certain identifying physical features.

A Conceptual Model of Angelman Syndrome and Review of Relevant Clinical Outcomes Assessments (COAs).

Background: Angelman syndrome (AS) is a rare, neurological genetic disorder for which no clinical outcomes assessments (COAs) or conceptual models (CM) have been developed.

Objective: This study aimed to identify symptoms and impacts relevant and important in this patient population and develop a conceptual model of AS, and to evaluate the content validity of selected COA instruments with potential for inclusion in clinical studies of AS to capture treatment benefit.

Methods: For both concept elicitation (CE) and cognitive interviews (CI), caregivers of children, adolescents, and adults with AS and clinicians with AS experience were targeted.

A Retrospective, Longitudinal, Claims-Based Comparison of Concomitant Diagnoses Between Individuals with and Without Down Syndrome.

Background: Individuals with Down syndrome (DS) experience various comorbidities in excess of the prevalence seen among the non-DS population. However, the extent of the excess burden of comorbidities specifically within commercially and publicly insured DS populations aged < 21 years is not currently known.

Objectives: To (a) describe the most common diagnoses among individuals with DS who have either commercial or Medicaid insurance and (b) compare the prevalence of those diagnoses between DS cases and non-DS controls.

Arbaclofen in fragile X syndrome: results of phase 3 trials.

Background: Arbaclofen improved multiple abnormal phenotypes in animal models of fragile X syndrome (FXS) and showed promising results in a phase 2 clinical study. The objective of the study is to determine safety and efficacy of arbaclofen for social avoidance in FXS.

Methods: Two phase 3 placebo-controlled trials were conducted, a flexible dose trial in subjects age 12-50 (209FX301, adolescent/adult study) and a fixed dose trial in subjects age 5-11 (209FX302, child study).

Parental Perspectives on Pharmacological Clinical Trials: a Qualitative Study in Down Syndrome and Fragile X Syndrome.

Research studies focusing on parents' perspectives of pharmacological clinical trials have not kept pace with the number of emerging pharmacologic clinical trials in Down syndrome (DS) and Fragile X syndrome (FXS). Since individuals with DS or FXS have limited cognitive ability to make decisions about their participation in clinical trials, it is important to consider the parents' perspectives and explore the ways in which decisions are made for their children. Using a semi-structured interview, we enrolled 9 parents of a child(ren) with FXS and 15 with a child with DS to analyze their views, experiences, and knowledge of pharmacological clinical trials.

Importance of a specialty clinic for individuals with fragile X syndrome.

Advances in human genetics have identified a significant number of genetic disorders associated with intellectual disability. As a result, appropriate clinical management of these affected individuals and their family members have become critical in addressing medical needs to improve quality of life. We examine the importance of a Fragile X Clinic for individuals with fragile X syndrome (FXS) and their family members by conducting a retrospective chart review of 123 new patients with FXS evaluated at the Fragile X Clinic at Emory University.

Mavoglurant in fragile X syndrome: Results of two randomized, double-blind, placebo-controlled trials.

Fragile X syndrome (FXS), the most common cause of inherited intellectual disability and autistic spectrum disorder, is typically caused by transcriptional silencing of the X-linked FMR1 gene. Work in animal models has described altered synaptic plasticity, a result of the up-regulation of metabotropic glutamate receptor 5 (mGluR5)-mediated signaling, as a putative downstream effect. Post hoc analysis of a randomized, placebo-controlled, crossover phase 2 trial suggested that the selective mGluR5 antagonist mavoglurant improved behavioral symptoms in FXS patients with completely methylated FMR1 genes.

Assessment of Cognitive Scales to Examine Memory, Executive Function and Language in Individuals with Down Syndrome: Implications of a 6-month Observational Study.

Down syndrome (DS) is the most commonly identifiable genetic form of intellectual disability. Individuals with DS have considerable deficits in intellectual functioning (i.e.

A 3' untranslated region variant in FMR1 eliminates neuronal activity-dependent translation of FMRP by disrupting binding of the RNA-binding protein HuR.

Fragile X syndrome is a common cause of intellectual disability and autism spectrum disorder. The gene underlying the disorder, fragile X mental retardation 1 (FMR1), is silenced in most cases by a CGG-repeat expansion mutation in the 5' untranslated region (UTR). Recently, we identified a variant located in the 3'UTR of FMR1 enriched among developmentally delayed males with normal repeat lengths.

Neurodevelopmental outcomes in children with Down syndrome and infantile spasms.

Down syndrome (DS) is the most common genetic cause of intellectual disability in the United States. The prevalence of seizure in individuals with DS is 1-13%, and infantile spasm (IS) occurs in 6-32% of those with seizures. Since IS is relatively common in children with DS, it is important to understand the impact IS has on the neurodevelopmental outcomes in order to provide appropriate anticipatory guidance to help maximize the potential of these children.

Sleep profiles in children with Down syndrome.

Down syndrome (DS) is the most common genetic cause of intellectual disability and results from an extra chromosome 21 (Trisomy 21). Sleep issues and/or obstructive sleep apnea (OSA) are assumed to be part of the DS phenotype with a high prevalence but are often under recognized. This cross-sectional study of children with DS examines the caregiver-reported sleep behaviors of 108 children with DS, ranging in age from 1.

Influence of CHDs on psycho-social and neurodevelopmental outcomes in children with Down syndrome.

Objective: To evaluate the family psycho-social outcomes of children with Down syndrome and atrioventricular septal defect, and examine the impact of these variables on the child's neurodevelopmental outcome.

Methods: This was a cross-sectional study that consisted of 57 children with Down syndrome - 20 cases and 37 controls - of ~12-14 months of age. In both groups, we assessed the development of the child, the quality of the child's home environment, and parenting stress.

Independent role for presynaptic FMRP revealed by an FMR1 missense mutation associated with intellectual disability and seizures.

Fragile X syndrome (FXS) results in intellectual disability (ID) most often caused by silencing of the fragile X mental retardation 1 (FMR1) gene. The resulting absence of fragile X mental retardation protein 1 (FMRP) leads to both pre- and postsynaptic defects, yet whether the pre- and postsynaptic functions of FMRP are independent and have distinct roles in FXS neuropathology remain poorly understood. Here, we demonstrate an independent presynaptic function for FMRP through the study of an ID patient with an FMR1 missense mutation.

Cognitive aspects of Fragile X syndrome.

Fragile X syndrome (FXS) is the leading inherited cause of intellectual disability. It is primarily caused by the expansion of a CGG trinucleodide repeat located in the 5' untranslated region of the X-linked FMR1 gene. Individuals with FXS present with variable intellectual quotients (IQs) ranging from the average to the severe intellectual disability level.

Implications of delayed diagnosis of infantile spasm in a child with Down syndrome.

Trisomy 21, leading to Down syndrome (DS) is the most common genetic cause of intellectual disability. Approximately 1-13% of children with DS have co-morbid seizures, with infantile spasm being the most frequent type of seizure identified. Although the clinical and electroencephalography findings of infantile spasm are similar between children with DS and typically developing children, there is often a delay in the diagnosis of these seizures in children with DS.

Fragile X syndrome: a review of associated medical problems.

Fragile X syndrome (FXS) is the most common known genetic cause of inherited intellectual disability and the most common known single-gene cause of autism spectrum disorder. It has been reported that a spectrum of medical problems are commonly experienced by people with FXS, such as otitis media, seizures, and gastrointestinal problems. Previous studies examining the prevalence of medical problems related to FXS have been challenging to interpret because of their marked differences in population, setting, and sampling.

Object-related generativity in children with Down syndrome.

Children with Down syndrome (DS) show challenges in some aspects of goal-directed behavior when compared to developmentally matched children (Daunhauer et al., 2014; Lee et al., 2011), particularly in the area of goal-directed action on objects (Fidler et al.

Contribution of Family History in Co-occurring Down Syndrome and Ehlers-Danlos Syndrome.

Nearly all children with Down syndrome (DS) are born with hypotonia which later improves with age. We present a case of a 32-month-old female with DS who has persistent hypotonia and ligamentous hyperlaxity. She was subsequently diagnosed with Ehlers-Danlos Syndrome-Hypermobility type (EDS-HMT) based on family history, which resulted in the significant global developmental delay compared to age-matched peers with DS.

A Case of False Negative NIPT for Down Syndrome-Lessons Learned.

Down syndrome or trisomy 21 is the most common cause of prenatal chromosome abnormalities with approximately 50% of all reported chromosome conditions. With the successful introduction of noninvasive prenatal testing (NIPT) for Down syndrome into routine prenatal care, it is important to understand the risks, benefits, and limitations in order to guide patients in making an informed decision. Herein, we describe the first published case report of a patient whose fetus tested "negative" for Trisomy 21 by NIPT but was diagnosed postnatally with trisomy 21.

Climbing the branches of a family tree: diagnosis of fragile X syndrome.

Objective: To determine the average number of family members diagnosed with a Fragile X Mental Retardation-1 (FMR1) mutation after a proband receives the initial diagnosis of fragile X syndrome (FXS).

Study Design: We reviewed pedigrees of families who had been evaluated at the Fragile X Syndrome Center at Emory University in Atlanta, Georgia. Through these pedigrees, we determined the number of additional family members diagnosed as FMR1 premutation carriers or with full mutation FXS after the initial diagnosis in each proband.