Comparison of the effects of acarbose and voglibose on plasma glucose, endogenous insulin sparing, and gastrointestinal adverse events in obese subjects: a randomized, placebo-controlled, double-blind, three-way crossover study

Abstract

Background: The pharmacologic effects and incidence of adverse abdominal events associated with these 2 alpha-glucosidase inhibitors have been reported to differ. This difference may have been due to different doses of the 2 drugs in our previous study. Objective: The objective of this randomized, placebo-controlled, double-blind, 3-way crossover study was to compare the pharmacologic effects and adverse events of the alpha-glucosidase inhibitors acarbose and voglibose. Methods: This 7-day study, with a 1-week period between treatments, was performed in 12 obese male volunteers. To assess the pharmacologic effects, plasma immunoreactive insulin (IRI), plasma glucose, and 24-hour urinary connecting-peptide immunoreactivity (CPR) excretion were measured. Results: Plasma glucose profiles were significantly lower when acarbose and voglibose were administered compared with placebo at both breakfast and dinner on days 1 and 7 ( P < 0.001). The plasma IRI profiles were significantly reduced ( P < 0.001) by acarbose and voglibose compared with placebo at both breakfast and dinner on day 7. Acarbose reduced 24-hour urinary CPR excretion by 26% and 40% on days 1 and 7, respectively, compared with day 0 when no drugs were given. Voglibose reduced 24-hour urinary CPR excretion by 7% and 25% on days 1 and 7, respectively, compared with day 0. Flatus score increased significantly (days 1 and 2, P < 0.01; days 3 and 4, P < 0.05) in patients given acarbose compared with day 0; it did not increase significantly in those given voglibose or placebo. There was no significant difference in stool scores between the acarbose and voglibose groups. Conclusions: Inhibition of postprandial plasma glucose and IRI rise and reduction of urinary CPR excretion were more potent with acarbose than with voglibose at current clinical doses.