neural biomarkers in fragile x syndrome

Conditions: Fragile X Syndrome (FXS); Neurotypical Adults

Summary: the purpose of this non-interventional test /re-test study is to assess neural biomarkers in adult subjects with fragile x syndrome compared to those measured in a population of typically developing adults

this study consists of a screening period and two cross sectional evaluations assessed in one month interval (test/re-test), first on the visit 1 (basal) and the other on the visit 2 (end-of-study visit, eos).

Eligibility criteria:
demographics common to all subjects: * male or female subjects. * age ≥ 18 and ≤ 55 years. * weight ≥ 50 kg and ≤ 100 kg. * body mass index (bmi) ≥ 18.5 and ≤ 30. subjects with fragile x syndrome inclusion criteria: * clinical and molecular diagnosis of fragile x syndrome (\> 200 cgg repeats in the promoter region of the fmr1 gene). * legal representative understands and accepts the study procedures. if only one parent signs, he/she should confirm that the other parent does not object to the patient's participation in the research project. * subject assenting and/or willing to participate. * signed informed consent by a legal representative before any study-mandated procedure. * subject is independently mobile and has sufficient vision and hearing to participate in study evaluations. they must be able to be understood most of the time and must not use other forms of communication, signs, symbol boards or devices as their primary form of communication. * subjects must have a parent, or other reliable caregiver, who agrees to accompany the subject to all study visits, provide information about the subject as required by the protocol, and ensure compliance with study tests. * subjects are expected to complete all procedures scheduled during the study visits. subjects with fragile x syndrome exclusion criteria: * personal history of infantile spasms/convulsions/epilepsy, severe head trauma or cns infections (e.g. meningitis), with the exception of infantile febrile seizures. * subjects with a current diagnosis including severe autism spectrum disorder or any primary psychiatric diagnosis according to dsm-5 (diagnostic and statistical manual of mental disorders-dsm-5). diagnoses that are secondary, such as attention deficit hyperactivity disorder, depressive disorders and conduct disorders are allowed as long as they are considered to not interfere with study conduct and are stable during the 3 months before inclusion. related allowed treatments must be on stable dosing for the last 3 months. * substance use disorder according to the dsm-5 criteria. * epileptiform abnormalities (excluding isolated sharp waves and beyond those expected for age). * any life-threatening disease. * any other clinically relevant concomitant disease or condition or finding at screening that in the judgment of the investigator could interfere with, the treatment thereof might interfere with, the conduct of the study and related procedures and/or might bias the study results interpretation, or could jeopardize the subject's safety. * any clinically significant findings in physical examination including vital signs. * neuroleptic or antidepressant (isrs) drugs within 3 months before inclusion, except for sertraline at a maximum 100 mg/day, and stable for the last 3 months before inclusion. * any prescription or over-the-counter drug (except occasional use of paracetamol) in the last 2 weeks before screening. * patient included in a clinical study with drugs in the last three months prior to inclusion. typically developing subjects inclusion criteria: * abstinence for any drug abuse 72 hours prior to the screening visit and the observation days, except for nicotine (24 hours). * able to read spanish and/or catalan and to adhere to the study requirements. * signed informed consent prior to any study-mandated procedure. typically developing subjects exclusion criteria: * life-time clinically significant cardiovascular, renal, pulmonary, hepatic, onco-haematological, endocrine, gastrointestinal, mental or neurological disease. * any other clinically relevant concomitant disease or condition or finding at screening that in the judgment of the investigator could interfere with, the treatment thereof might interfere with, the conduct of the study and related procedures and/or might bias the study results interpretation, or could jeopardize the subject's safety. * any clinically significant findings in physical examination including vital signs. * neuroleptic drugs within 3 months prior to inclusion. * any prescription or over-the-counter drug (except occasional use of paracetamol) in the last 2 weeks before screening. * patient included in a clinical study with drugs in the last three months before inclusion. * personal history of infantile spasms/convulsions/epilepsy, severe head trauma or cns infections (e.g. meningitis), except for infantile febrile seizures. * subjects with a current diagnosis including autism spectrum disorder or any primary psychiatric diagnosis according to dsm-5 (diagnostic and statistical manual of mental disorders-dsm-5). diagnoses that are secondary, such as attention deficit hyperactivity disorder, depressive disorders and conduct disorders are allowed as long as they are considered to not interfere with study conduct and are stable during the 3 months before inclusion. related allowed treatments must be on stable dosing for the last 3 months. * substance use disorder according to the dsm-5 criteria except for mild alcohol use disorder and/or mild or moderate nicotine use disorder. * positive urine test for drugs of abuse or alcohol breath test at screening. * epileptiform abnormalities (excluding isolated sharp waves and beyond those expected for age). * any life-threatening disease.

Keywords: fragile x syndrome fxs fragile x neurodevelopmental disorders central nervous system diseases intellectual disability neurobehavioral manifestations genetic diseases, x-linked congenital abnormalities orphan diseases rare diseases neural biomarkers