Metformin–acarbose better than existing combinations in Type 2 diabetes
MedWire News: The combination of metformin and acarbose in patients with Type 2 diabetes appears to control glucose variability more effectively than the established combination of metformin and glibenclamide, study results show.
The novel combination also showed benefits in terms of weight reduction and shorter durations of hyperglycemia, report Ming-Chia Hsieh (Changhua Christian Hospital, Taiwan) and colleagues.
The American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) recommend prescription of metformin as initial treatment for Type 2 diabetes along with lifestyle modification. If glycemic goals are not met, they suggest adding either basal insulin or a sulfonylurea.
However, this "does not allow for individualizing and optimizing therapy with respect to sustaining glycemic control and the reduction of glucose variability," Hsieha et al note in the Journal of Diabetes and its Complications.
Acarbose, which belongs to another class of drug, the α-glucosidase inhibitors, decreases the postprandial increment in plasma glucose by delaying the intestinal absorption of carbohydrates, explain the researchers. Although early studies have been promising, there have been no head-to-head trials comparing such newer drug combinations with the metformin-sulfonylurea combination, they say.
The team therefore conducted a randomized, open-label study involving 40 outpatients with Type 2 diabetes who had been treated with one or two oral antidiabetic drugs for at least 3 months and whose glycated haemoglobin (HbA1c) levels were in the range 7.0% to 11.0%.
After enrolment, all patients received metformin 500 mg three times per day during an 8-week run-in period. They were then randomly assigned to receive either acarbose 100 mg or glibenclamide 5 mg three times per day, while continuing metformin.
After the 16-week treatment period, HbA1c had improved significantly in both the glibenclamide and acarbose groups, at 7.5% and 7.3%, respectively, relative to the metformin alone run-in period.
However, glucose variability, expressed as mean amplitude of glycemic excursion or continuous overall net glycemic action and mean of daily differences, decreased significantly after the addition of acarbose but not glibenclamide.
The acarbose-metformin combination had the additional benefit of weight reduction and shorter durations of hyperglycemia compared with metformin monotherapy, which was not observed in the glibenclamide group.
"From the standpoint of glucose-lowering effect, treatment adherence, safety, and adverse effects, combining metformin with acarbose appears to be a more appropriate treatment strategy than combining with glibenclamide," Hsieha et al conclude.
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By Andrew Czyzewski