Long‐term (52‐week) efficacy and safety of ipragliflozin add‐on therapy to insulin in Japanese patients with type 1 diabetes mellitus: An uncontrolled, open‐label extension of a phase III study

INTRODUCTION: The aim of the present study was to assess the long‐term (52‐week) efficacy and safety of ipragliflozin in insulin‐treated Japanese patients with type 1 diabetes mellitus and inadequate glycemic control. MATERIALS AND METHODS: In this 28‐week, open‐label extension of a multicenter, randomized, placebo‐controlled, 24‐week phase III study, ipragliflozin recipients continued treatment (50 mg, once daily), and placebo recipients were switched to once‐daily 50 mg ipragliflozin at the start of the extension period. The ipragliflozin dose could be increased to 100 mg if warranted. The primary end‐point was change in glycated hemoglobin; secondary end‐points were change in insulin dose and bodyweight. Safety outcomes were monitored as treatment‐emergent adverse events. RESULTS: A total of 53 (placebo switched to ipragliflozin) and 108 (ipragliflozin) patients completed the open‐label extension (treatment period 2), with 24 and 44 patients, respectively, receiving dose increases. From baseline to end of treatment, the overall mean change (standard deviation [SD]) in glycated hemoglobin was −0.33% (0.72; −3.7 mmol/mol [7.9]), with changes in basal, bolus and total insulin doses of −3.76 IU (SD 3.85 IU), −2.51 IU (SD 7.08 IU) and −6.27 IU (SD 8.16 IU), respectively. No serious drug‐related treatment‐emergent adverse events or deaths were reported. Treatment‐emergent adverse events leading to study discontinuation occurred in zero and three (2.6%) patients in the placebo switched to ipragliflozin and ipragliflozin groups, respectively; all were considered drug‐related. There were no cases of severe hypoglycemia or diabetic ketoacidosis, and no safety concerns related to dose increase. CONCLUSIONS: The efficacy and safety of 50 mg, once‐daily ipragliflozin in insulin‐treated type 1 diabetes mellitus patients were confirmed in this long‐term, open‐label extension study. No safety concerns were attributed to a dose increase to 100 mg.