Comparative effectiveness of Glargine 300 U/mL vs. Degludec 100 U/mL in patients with type 2 diabetes switching from 1° generation basal insulins

Background and aims: Data on second generation basal insulin (2BI) in people with type 2 diabetes (T2D) generated by clinical trials still need confirmation in real-world clinical settings. This study aimed at assessing the comparative effectiveness of 2BI [Glargine 300 U/mL (Gla-300) vs. Degludec 100 U/mL (Deg-100)] in T2D Italian patients switching from first generation basal insulins (1BI).

Methods and results: This was a retrospective, non-inferiority, multicenter study. Patients switching to Gla-300 or Deg-100 from 1BI were 1:1 propensity score matched (PSM). Changes during 6 months in continuous endpoints were assessed through linear mixed models. Incidence rates (IR) of hypoglycemia (episodes per patient-months) were compared using Poisson regression. Each PSM cohort included 593 patients. HbA1c decreased from baseline (8.7%) to 6 months by -0.58% (95%CI -0.69;-0.47) in Gla-300 group and -0.50% (95%CI -0.61;-0.39) in Deg-100 group, confirming the non-inferiority of Gla-300 vs. Deg-100. No between-group differences emerged: FBG was reduced by about 20 mg/dl with both 2BI, mean dose of 2BI (24.5 U, 0.3 U/Kg at the first prescription) was suboptimally titrated during 6 months (+1.34 U in Gla-300 and + 1.76 U in Deg-100), body weight showed minor changes. IR of hypoglycemia <54 mg/dl was 0.32 (95%CI 0.21; 0.49) in Gla-300 group and 0.19 (95%CI 0.11; 0.33) in Deg-100 group (p = 0.14).

Conclusion: In subjects with T2D, switching to 2BI from 1BI was associated with similar improvements in glycemic control, low hypoglycemia rates and no weight gain in real-life setting. Clinical inertia, represented by late treatment intensification and suboptimal titration, represents a major issue in Italy.