Metformin and rosiglitazone, used together, were more effective in treating youth with recent-onset type 2 diabetes than metformin alone, U.S. researchers say. Dr. Philip Zeitler, study chairman and a pediatric endocrinologist at Children\'s Hospital Colorado, in Aurora, said the study found metformin therapy alone was not an effective treatment for many of the youth affected by the illness. The Treatment Options for type 2 Diabetes in Adolescents and Youth study is the first major comparative effectiveness trial for the treatment of type 2 diabetes in young people. The study tested how well and for how long each of three treatment approaches controlled blood glucose levels in subjects ages 10-17 with type 2 diabetes. Participants were randomly assigned to one of three treatment groups -- metformin alone, metformin and rosiglitazone together, and metformin plus intensive lifestyle changes aimed at helping participants lose weight and increase physical activity. The study, published in the New England Journal of Medicine, found treatment with metformin alone was inadequate for maintaining acceptable, long-term, blood glucose control in 51.7 percent of youth during an average follow-up of 46 months. The failure rate was 38.6 percent in the metformin and rosiglitazone group, a 25.3 percent reduction in the rate for metformin alone. In the metformin-plus-lifestyle group the failure rate was 46.6 percent.