Safety and Efficacy Study of Antioxidants for the Treatment of the Fragile X Syndrome

The Fragile X syndrome (FXS) was first described by Dr. Martin and Dr. Bell in 1943, in families with several patients affected by sex-linked mental disability. This disorder is the most common cause of inherited mental disability. The prevalence of the Fragile X syndrome has been established at 1 in 2,500 males and 1 in 4000 females. Despite moderate to severe mental retardation, fragile X patients exhibit macroorchidism, an elongated face, long ears, connective tissue dysplasia, hyperactivity, autistic-like and stereotypical behaviours, speech delay and increased sensory sensitivity. Objective: To evaluate the effect of the combination of the antioxidant Ascorbic acid and tocopherol, as therapy of the Fragile X Syndrome in young males. Hypothesis: It is proposed that part of the pathophysiology of the central nervous system in the animal model of the fragile X syndrome may be determined by oxidative stress. In addition, Fragile X patients showed a significantly low level of ascorbic acid in plasma. The biochemical characteristics of oxidative stress may be reversed in the FMR1-KO mice, by a chronic treatment with antioxidant compounds such as tocopherol or melatonin, it may also normalize several hallmarks of the Syndrome such as hyperactivity, anxiety and cognitive deficits. The normalization of the oxidative stress is proposed as a new therapeutic pathway to alleviate conditions caused by an excess of free radicals that are crucial in neurodevelopmental diseases such as autism, down syndrome and other diseases of the central nervous system.

* Objective: To evaluate the effect of the combination of the antioxidant Ascorbic acid and tocopherol, as therapy of the Fragile X Syndrome in young males. * Design: Pilot clinical trial, Phase II , 6-month randomized, double-blind placebo-controlled one-way crossover clinical trial, with two treatment periods of 12 weeks duration. * Setting: IMABIS Foundation. Carlos Haya Hospital, Malaga. * Subjects: Children aged 5-11 years (infants) and 12-18 years (adolescents) diagnosed with Fragile X syndrome. * Intervention: 30 participants randomly assigned, to receive antioxidant vitamins C (ascorbic acid) and vitamin E (d-alpha-tocopherol) once a day or placebo for 12 weeks double-blind. In Study Period 2, all participants receive (open) active treatment. Outcome measures: improvement in plasma antioxidant levels, oxidative stress (indicated by glutathione status, thiobarbituric acid reacting substances (TBARS) and carbonyl content of proteins) and HPA axis response. Behavioral problems will be studied using "Developmental behavior checklist" and "Teacher's and Parent´s Questionnaire, C. Keith Conners", also learning improvement will be analyzed using "Wechsler Intelligence Scale for children" at 0, 3, 6 months during the trial and 3 months after completing the treatment.