A university study has concluded that a combination of metformin and rosiglitazone (Avandia) is the best drug therapy for controlling blood sugar levels in type 2 children and adolescents. Metformin alone is the drug most often prescribed for young or recently diagnosed type 2 patients.
While the study by researchers at George Washington University and the University of Colorado shows that a combination therapy is more effective, the inclusion of rosiglitazone raises some concerns. The drug, a member of the thiazolidinedione (TZD) drug class, has been linked in Europe and the United States to an increased risk of cardiovascular problems.
The researchers began the study in 2002, before problems with TZDs were suspected. The drug was selected as a combination therapy alternative to sulfonylureas, which produce excessively high levels of hypoglycemia in young type 2s.
The TODAY (Treatment Options for Type 2 Diabetes in Adolescents and Youth) study, which involved 699 patients ages 10 to 17, examined three factors:
• The efficacy of metformin as a standalone therapy for type 2
• The efficacy of metformin and “lifestyle intervention”-changes in diet and exercise
• The efficacy of metformin and rosiglitazone as a combination therapy
The participants were split randomly into three groups. One group took metformin alone twice daily (1,000 mg), a second took the same dose of metformin plus four mg of rosiglitazone daily, and the third group took the same dose of metformin and worked on lifestyle changes that could lead to weight loss. The goal of each mode of treatment was to achieve and maintain an A1C level of less than 8%.
The researchers reported that the rate of treatment failure, wherein patients did not achieve the 8% A1C goal, favored the combination therapy group.
• 38.6 percent of patients in the metformin and rosiglitazone combination therapy group failed to achieve the A1C goal
• 46.6 percent of patients in the metformin plus lifestyle intervention group failed to achieve the A1C goal
• 51.7 percent of patients in the group taking metformin alone failed to achieve the A1C goal
Although the combination drug therapy worked best at blood sugar control, the study found that patients taking both drugs experienced greater weight gain than those in the other two groups. The combination therapy was more effective in girls than in boys, and metformin alone worked better in whites and non-white Hispanics than it did in black youths.
While the study helps establish combination therapy as a successful approach to treating type 2 in young people, there remains the task of finding a non-TZD drug to partner with metformin that can produce similar results.