A Propensity Score Matched Comparison of Brand and Biosimilar Basal Insulin in Non-Critical Hospitalized Patients with Type 2 Diabetes Mellitus

Introduction Comparisons between brand and biosimilar basal insulin in hospitalized patients are lacking. We aimed to compare the efficacy and safety of brand insulin glargine vs. biosimilar insulin glargine in non-critical hospitalized patients with type 2 diabetes mellitus (T2DM). Methods This retrospective study was conducted using the electronic medical records of 194,006 patients at the Qingdao Endocrine and Diabetes Hospital between January 2006 and December 2017. A total of 476 patients diagnosed with T2DM, hospitalized, and treated with subcutaneous insulin glargine were included. After propensity score matching (1:3), patients who received biosimilar insulin glargine (Basalin) ( n = 34) were compared to a matched group of patients who received brand insulin glargine (Lantus) ( n = 101). Outcome measures were changes in fasting blood glucose (FBG), the incidence of hypoglycemia, and insulin dose. Results Compared to patients who received Basalin, patients who received Lantus achieved more reduction in FBG during insulin treatment (− 1.24 mmol/L vs. − 2.20 mmol/L; p = 0.04) and had a lower mean FBG at the end of treatment (8.20 mmol/L vs. 7.26 mmol/L; p = 0.12). Patients in Basalin and Lantus groups had a comparable mean daily dose of basal insulin at initiation (0.19 vs. 0.18 IU/kg; p = 0.30) and end of treatment (0.21 vs. 0.21 IU/kg; p = 0.99), and a similar duration of basal insulin treatment (16.4 vs. 15.3 days; p = 0.74). Hypoglycemia was infrequent in both Basalin and Lantus treatment (one vs. four patients, respectively; p = 1.00) and no severe hypoglycemic events were reported. Conclusion In a non-critical hospital setting, subcutaneous treatment with Lantus brought significant FBG improvement without increased hypoglycemic risk.