Introduction: This study aimed to determine, in close to real-life conditions, the efficacy and safety of switching from any basal insulin to insulin glargine 300 U/mL (Gla-300) in patients with uncontrolled type 2 diabetes (T2D).

Methods: This was an interventional, multicenter, single-arm, prospective study with a 24-week treatment phase. Adult patients with T2D treated with basal insulin with or without other antidiabetics, HbA1c > 7.5%, and fasting self-monitored blood glucose (F-SMBG) > 130 mg/dL (mean of three measures) at baseline were included. Insulin dose was titrated to reach F-SMBG 90-130 mg/dL. Efficacy and safety were assessed at 12 weeks (W12) and 24 weeks (W24). The main outcome parameter was HbA1c change between baseline and W24. Safety parameters included self-reported hypoglycemia (any type). Patients' satisfaction with the treatment was assessed by the Diabetes Treatment Satisfaction Questionnaire (DTSQ).

Results: A total of 140 patients were included and 137 were treated. Mean HbA1c decreased from 8.64% at baseline to 8.14% at W12 (mean difference [95% CI] - 0.51% [- 0.64; - 0.38]) and 8.01% at W24 (- 0.64% [- 0.81; - 0.46]). _target F-SMBG was reached in 35.0% of the patients at W12 and 38.4% at W24. The percentages of patients reaching HbA1c levels < 7.0%, < 7.5%, and < 8.0% at W24 were 11.4%, 29.5%, and 50.8%, respectively, while only 31.6% had an HbA1c value < 8.0% at baseline. HbA1c reduction was greater in patients with higher baseline levels. During the treatment phase, 46.0% of the participants had at least one hypoglycemia event; 31.4% documented symptomatic hypoglycemia, 2.2% severe hypoglycemia, and 12.2% nocturnal hypoglycemia. Treatment satisfaction increased by 20% between baseline and W24.

Conclusion: These data, derived from close to real-life practice in France, confirm the reassuring results of randomized trials on the efficacy and safety of Gla-300.

Trial registration: EudraCT number 2015-002416-33.