Metformin and troglitazone were both shown to improve glycemic control of type 2 diabetes. In addition, using them in combination proved to be safe and to provide additional benefit.
Two weeks after test subjects were taken off their anti-diabetic therapy (mostly sulfonylureas) they were put on metformin or troglitazone for three months (monotherapy).
After three months the subjects taking metformin had troglitazone added to their therapy (MET-TGZ), and the subjects taking troglitazone had metformin added (TGZ-MET). This combined therapy lasted for three more months. No significant side-effects or adverse effects were seen when the drugs were used in combination.
After three months of monotherapy, both groups experienced improved fasting blood sugars (FBS) levels. Metformin lowered FBS by 19 percent, and troglitazone lowered FBS by 17 percent. BG levels after a meal were also improved. BG response to a meal was decreased by 62 percent for patients on metformin and by 56 percent for patients taking troglitazone.
After three months of combined therapy, subjects experienced even more decreases in FBS. The MET-TGZ group’s FBS dropped (from baseline) 32 percent and the TGZ-MET group’s dropped 42 percent. In addition, HbA1c levels dropped 13.2 percent in the MET-TGZ group and 16 percent in the TGZ-MET group compared to HbA1cs on prior therapy.