Twice-daily biphasic insulin aspart 30 plus metformin compared with once-daily insulin glargine in combination with glimepiride in type 2 diabetes
P Kann1, M Regulski2 & J Medding3
In patients failing on oral antidiabetic (OAD) medication, insulin therapy is frequently started by adding basal or premixed insulin preparations to existing OADs. The aim of the study was to compare the efficacy and safety of two insulin analogue regimens in 255 patients (131 male; mean±SD age, 61.2±9.1 yrs) with type 2 diabetes. All patients gave written, informed consent; the study was approved by a local Ethical Committee and was performed in accordance with the Declaration of Helsinki. In this randomised, open-label parallel study, twice-daily biphasic insulin aspart 30 plus metformin (30% soluble and 70% protaminated insulin aspart; BIAsp 30+ met; n=128) was compared with once-daily insulin glargine combined with once-daily oral glimepiride (glarg + glim; n=127) over 26 weeks. Mean baseline HbA1c (±SD) was 9.2±1.4% in the BIAsp 30+ met group and 8.9±1.3% in the glarg + glim group (p=ns). The primary endpoint was the mean difference in HbA1c between groups after 26 weeks treatment. HbA1c was significantly lower in the BIAsp 30+ met group than in the glarg + glim group: −0.51%; p=0.0002 (corrected for baseline and treatment effects). Mean prandial increment (average over 3 meals) was significantly lower for the BIAsp 30+met group compared with the glarg + glim group: −1.2 mmol/l vs. +0.2 mmol/l; p=0.0002. During the maintenance phase (from weeks 10–20), there was one major hypoglycaemic episode in each of the treatment groups. During the same phase, 20.3% and 9.0% of patients experienced minor hypoglycaemic episodes in the BIAsp 30+met and glarg + glim groups, respectively. Median total daily insulin doses were 25 U BIAsp 30 and 28 U glargine; median daily doses for the oral agents were 2000 mg met and 4.0 mg glim. Glar + glim-treated patients experienced a significant weight increase of 1.5 kg during the trial (95% CI: 0.81; 2.2). The weight change seen with BIAsp 30+met of +0.7 kg was not statistically significant (95% CI: −0.43; 1.38). In summary, starting insulin in type 2 diabetes patients with twice-daily BIAsp 30+met can reduce HbA1c and mean prandial glucose increment to a greater extent than once-daily glarg + glim.