NP27936: A randomized, double-blind, 12-week, parallel group, placebo-controlled study of the efficacy and safety of RO4917523 in patients with Fragile X Syndrome

Principal Investigator: Michael Johnston

The purpose of this study is to evaluate the efficacy of 12-week treatment with RO4917523 in patients with Fragile X Syndrome (FXS) as measured by the Anxiety Depression and Mood Scale (ADAMS) social avoidance factor, as well as to evaluate the safety and tolerability of RO4917523 in patients with FXS. There will be three study phases: Screening Phase, Treatment Phase, and Follow-up Phase. During the treatment period, blinding will be maintained by randomly allocating subjects to receive either RO4917523 or placebo. The participants will meet with the study doctor about every 2 to four weeks and will be monitored for side effects. Participants will also meet with the study doctor three weeks after last dose for a follow-up visit. Visits will consist of physical and medical exams (including blood draws, urine and ECG testing) and behavioral assessments.