Titration of insulin glargine 100 U/mL when added to oral antidiabetic drugs in patients with type 2 diabetes: results of the TOP-1 real-world study

Aims Adequate insulin titration is crucial for optimal glycaemic control in type 2 diabetes (T2D). We aimed to explore the factors and outcomes associated with titration of glargine 100 U/mL (Gla-100) in patients uncontrolled on oral antidiabetic drugs (OAD) and initiating insulin therapy. Methods Patients from the Titration and Optimization (TOP)-1 registry were stratified by the magnitude of Gla-100 up-titration during the first month (no [< 1 Units (U)/day (d)], minimal [>= 1 and < 5 U/d], moderate [>= 5 and <= 8 U/d] and strong [> 8 U/d]). The primary endpoint was a fasting blood glucose (FBG) <= 110 mg/dL on >= 2 occasions and/or individual HbA1c target by 12 months. Results Of 2308 patients, 905, 715, 409 and 279 underwent no, minimal, moderate and strong titration, respectively. Age decreased across increasing titration groups (p = 0.02) while body mass index (BMI) (p < 0.0001), FBG (p < 0.0001), and HbA1c (p < 0.0001) increased. At 12 months, the proportions of patients achieving the primary endpoint were comparable across groups (66.1% overall), though a smaller proportion of no titration patients met both their individual HbA1c target and FBG <= 110 mg/dL compared to moderate and strong titration patients (20.1% vs. 27.2% and 26.2%, p = 0.033 and 0.023, respectively). HbA1c was also comparable, though FBG was higher in the no titration group (126.2 vs. 122.6, 121.5 and 120.9 mg/dL, p < 0.02). A similar, small reduction in body weight occurred in all groups; hypoglycaemia rates were comparable across groups. Conclusions In real-world, titration of Gla-100 during the first month appears to coincide with a number of baseline factors. Insulin dose to meet HbA1c and FBG targets remains suboptimal in the majority of T2D patients.