Real-world study of the concomitant use of biphasic insulin as part 30/70 with GLP-1 receptor agonist versus first-generation basal insulin with GLP-1 receptor agonist in type 2 diabetes

Aims: Combining insulin with a glucagon-like peptide-1 receptor agonist (GLP-1RA) to treat type 2 diabetes (T2D) is common. While many studies have investigated concomitant therapy with basal insulin+GLP-1RA, few have reported on premixed insulin+GLP-1RA. We aimed to address this gap using data from the Clinical Practice Research Datalink Aurum database in England.Methods: This retrospective cohort study with propensity score matching assessed glycaemic levels and other clinical outcomes in people with T2D, comparing biphasic insulin aspart 30/70 (BIAsp 30) + GLP-1RA with basal insulin (insulin detemir/glargine U100) + GLP-1RA (from 2006 to 2021).Results: In total, 4770 eligible people were identified; 1511 had a BIAsp 30 + GLP-1RA regimen and were propensity score-matched to an equal number receiving basal+GLP-1RA. There was no significant difference in glycated haemoglobin (HbA1c) reduction between cohorts at 6 months (p = 0.15), with a decrease of -1.07 (95% CI: -1.16; -0.98) %-points (-11.7 mmol/mol [95% CI: -12.7; -10.7]) in the BIAsp 30 + GLP-1RA cohort, versus -0.97 (95% CI: -1.07; -0.88) %-points (-10.6 mmol/mol [95% CI: -11.7; -9.6]) in the basal+GLP-1RA cohort. Body mass index (BMI) decreased by -0.35 kg/m2 (95% CI: -0.52;-0.18) at 6 months with BIAsp 30 + GLP-1RA, versus -0.72 kg/m2 (95% CI: -0.90;-0.54) with basal+GLP-1RA (p = 0.003). BMI was influenced by the initiation sequence of GLP-1RA in relation to insulin (p < 0.0001). Hypoglycaemia rates were low and not significantly different between cohorts.Conclusions: Combining BIAsp 30 + GLP-1RA provides glycaemic control with no significant difference to that of propensity score-matched people receiving basal insulin+GLP-1RA, with no increase in hypoglycaemia risk or weight gain.