A Study of RO5186582 in Down Syndrome Among Children 6 to 11 Years of Age

This study will evaluate the safety, tolerability, efficacy, and pharmacokinetic and pharmacodynamic activity of 3 different dosages of RO5186582 compared with placebo. A total of approximately 46 participants will be enrolled, in order to have at least 32 evaluable, and will be randomly assigned to 1 of 4 treatments in a 1:1:1:1 ratio, with 9 children per treatment arm. The target ratio between 6-8 years and 9-11 years age groups is approximately 1:1 in each treatment arm, with a minimum of 3 children per age group in each treatment arm.