Safety and glycemic control with insulin degludec use in clinical practice: results from a 3-year Japanese post-marketing surveillance study.

Introduction: Insulin degludec (degludec) is a basal insulin with a long duration of action. This post-marketing surveillance study monitored safety and glycemic control during use of degludec for 3 years in normal clinical practice in Japan. Materials and methods: This multicenter, open-label, observational study included patients with diabetes receiving degludec in Japan between 2013 and 2019. The primary outcome was incidence of adverse events occurring over 3 years of treatment. The pre-specified, secondary outcomes were severe hypoglycemic episodes and changes in HbA1c and fasting plasma glucose levels. Results: Of 4167 patients enrolled, 4022 were included in the safety assessments and 3918 in the assessments of glycemic control. Mean age was 58.9 years; 74.1% of patients had type 2 diabetes, and mean HbA1c at baseline was 8.7%. Adverse events and serious adverse events were observed in 19.1% and 8.9% of patients, respectively. Cardiac disorders and neoplasms were reported in 2.0% and 1.8% of patients, respectively, with the majority of these incidents reported as serious adverse events. Adverse drug reactions were seen in 8.0% of patients, mainly hypoglycemia. Hypoglycemic events were observed in 5.6% of patients, and severe hypoglycemic events in 1.7%. No serious allergic or injection-site reactions were seen. Respective changes (from baseline to 3 years' observation) in HbA1c and fasting plasma glucose levels were - 0.55% and - 36.3 mg/dL, and 19.6% of patients reached HbA1c < 7.0%. Conclusions: Using degludec for 3 years in normal clinical practice had a good safety and tolerability profile. Improvements in glycemic control were also seen. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-023-00657-7.