Introduction: Dapagliflozin is an orally active inhibitor of sodium-glucose co-transporter 2 (SGLT2) that is indicated for use in adults with type 1 diabetes (T1DM) (with a body mass index (BMI) of at least 27 kg/m2 in Europe, no such BMI limit in Japan), when insulin alone does not provide adequate glycaemic control. The aim of this study was to evaluate changes in glycated haemoglobin (HbA1c), body weight and insulin dose following discontinuation of dapagliflozin for the management of T1DM in the DEPICT clinical trial programme.
Methods: The interrelationship between treatment discontinuation, insulin requirement and outcomes post-discontinuation was evaluated using descriptive summary statistics and linear regression modelling. Data were analysed from individuals with T1DM discontinuing dapagliflozin in DEPICT-1 or DEPICT-2 (unplanned or end of study). HbA1c and body weight were measured over the 56-week study period (consisting of a 52-week treatment period and a 4-week follow-up period) at 4-8 weekly intervals. Following discontinuation of dapagliflozin, 1-year change in HbA1c (%) and weight (kg) following discontinuation of dapagliflozin was estimated; total daily insulin doses were descriptively summarised.
Results: Of the 1059 individuals that received dapagliflozin during the DEPICT trials 91 met the eligibility criteria and were included in the analyses of HbA1c and body weight. The mean duration of follow-up was 209 days in both analyses. Following dapagliflozin discontinuation, estimated annualised changes in HbA1c and body weight were + 0.99% (95% CI 0.39, 1.59) and + 3.75 kg (1.65, 5.86), respectively. An increase in insulin dose was observed around the time of discontinuation; insulin dose in the 2-week post-discontinuation was + 3.6 IU and + 4.4 IU higher with dapagliflozin 5 mg and 10 mg than 2 weeks pre-discontinuation, respectively.
Conclusion: Discontinuation of dapagliflozin is predicted to lead to clinically meaningful increases in HbA1c and body weight, in addition to higher insulin doses. These findings are important in the management of people with T1DM among whom insulin is the only existing pharmacological treatment option.
Keywords: Body weight; Dapagliflozin; HbA1c; Treatment discontinuation; Type 1 diabetes mellitus.