Aim: To compare the efficacy of combination therapy using rosiglitazone (8 mg per day) and glibenclamide (7.5 mg per day) with upward titration of glibenclamide as monotherapy (maximum dose=15 mg per day) in reducing HbA(1c) levels over 26 weeks in patients with type 2 diabetes mellitus (T2DM).
Methods: Three hundred and forty patients with T2DM inadequately controlled (FPG > or =7.0 and < or =15.0 mmol/l) on glibenclamide 7.5 mg per day were randomised to either additional treatment with rosiglitazone 8 mg per day or up-titration of the glibenclamide dose (maximum dose=15 mg per day).
Results: After 26 weeks, treatment with rosiglitazone combination reduced HbA(1c) by 0.81% (P<0.0001) and FPG by 2.4 mmol/l (P<0.0001) compared with glibenclamide monotherapy. HOMA-S and HOMA-B increased by 12 and 28%, respectively (P<0.0001 for both) with combination compared with glibenclamide monotherapy. With rosiglitazone combination and glibenclamide monotherapy, total cholesterol: HDL ratio reduced by 5 and 13%, triglycerides reduced by 6 and 2%, and FFAs reduced by 15 and 8%, respectively. Both treatments were well tolerated and had predictable safety profiles.
Conclusion: For patients inadequately controlled on glibenclamide, addition of rosiglitazone provides significantly improved glycaemic control compared with uptitration of glibenclamide. This may be preferable to continued monotherapy with higher doses of glibenclamide.