Background: Basal insulin is the first choice for insulin initiation in type 2 diabetes (T2DM), with the second generation of basal insulin analogues having a lower risk of hypoglycemia compared to the first generation of basal insulins. The aim of our study was to assess on a large cohort of insulin-naïve T2DM subjects the effectiveness and safety of insulin glargine 300 U/mL (Gla-300) in a real-life setting.Methods: This was a multicenter, prospective, non-interventional, 24 weeks, 3 visits (baseline, 3 and 6 months) trial performed in adult T2DM subjects not achieving glycemic target (HbA1c >7%) with prior oral or GLP-1 RA therapy. The study included 1,095 subjects (55.2% M/44.8% F) in 124 study sites.Mean (±SD) age was 61.1±8.5 years while mean duration of diabetes was 8.8±5.2 years. Mean BMI was 31.7±5.4 kg/m 2 with 91.2% being overweight or obese. Baseline diabetes treatment included metformin (88.4% of subjects), sulphonylureas (75.4%), DPP-4i (16.7%) and GLP-1 RAs (8%). Comparison between quantitative variables was made with the paired sample t test.Results: Mean HbA1c at baseline was 9.8%±1.7% with a mean fasting plasma glucose (FBG) of 231.5±67.4 mg/dL. Mean HbA1c decreased to 7.7%±1.2% at 6 months with a mean change from baseline of −2.1% (P<0.001). Overall, 30.7% of subjects reached the HbA1c target of 7%. Final mean dose of Gla-300 was 0.4 IU/kg/day. Mean weight gain was 0.4 kg over 6 months. Adverse events (AEs) were reported by 11.1% of subjects with 2.3% reporting serious adverse events (SAEs). Overall, 4.4% of subjects reporting at least one event of symptomatic or confirmed hypoglycemia. Only 7 episodes of nocturnal and one of severe hypoglycemia were reported. Conclusions:In conclusion, a significant 2.1% decrease of HbA1c was recorded after 6 months of treatment with Gla-300 with no unexpected safety signals, low risk of hypoglycemia and modest weight gain.