A multicentre, UK, retrospective, observational study to assess the effectiveness of insulin glargine 300 units/ml in treating people with Type 1 diabetes mellitus in routine clinical practice (SPARTA).

Aim To conduct an open-label study to provide UK real-world evidence regarding the use of insulin glargine 300 units/ml (U300) in people with Type 1 diabetes mellitus. Methods People with Type 1 diabetes who had been prescribed U300 >= 6 months before data collection and had HbA(1c) levels recorded within 3 months prior to U300 (baseline) were included. The primary endpoint was change in HbA(1c) from baseline to month 6 after U300 initiation. Other endpoints included number of documented hypoglycaemic and diabetic ketoacidosis episodes, and change in daily basal insulin dose. Results A total of 298 people with Type 1 diabetes were included [mean age 42.1 years, mean HbA(1c) 79 mmol/mol (9.4%)]. After U300 initiation, the mean reduction in HbA(1c) from baseline to month 6 was -4 mmol/mol (-0.4%; Pn=188). The total daily basal insulin dose at 6 months was 1.3 units higher than at the time of U300 initiation (Pn=275) but was not significantly different from the prior basal insulin dose. There was no clinically significant difference in weight between baseline and month 6 [mean difference +0.7 kg, 95% CI -0.1, 1.5; P=0.084; n=115). During the 6 months before and after U300 initiation, severe hypoglycaemic episodes were documented for 6/298 and 4/298 participants. Diabetic ketoacidosis episodes requiring Accident and Emergency department visits or hospitalization were documented for 4/298 and 6/298 participants, before and after U300 initiation, respectively. Conclusions In people with Type 1 diabetes, a change in basal insulin to U300 was associated with clinically and statistically significant HbA(1c) improvements, without significant changes in basal insulin dose and weight. Documented severe hypoglycaemia episodes and diabetic ketoacidosis requiring Accident and Emergency department visits or hospitalization were low and similar before and after U300 initiation.