Twelve-Week Treatment With Liraglutide as Add-on to Insulin in Normal-Weight Patients With Poorly Controlled Type 1 Diabetes: A Randomized, Placebo-Controlled, Double-Blind Parallel Study

OBJECTIVE This study investigated the efficacy and safety of once-daily liraglutide 1.2 mg versus placebo as add-on to insulin treatment in normal-weight patients with poorly controlled type 1 diabetes.

RESEARCH DESIGN AND METHODS In a randomized (1:1), double-blind, placebo-controlled design, 40 patients with type 1 diabetes (HbA_1c ≥8% [64 mmol/mol]) received once-daily liraglutide 1.2 mg or placebo for 12 weeks. Continuous glucose monitoring was performed before and at the end of treatment. The primary end point was change in HbA_1c. Secondary end points included change in insulin dose, weight, glycemic excursions, heart rate, and blood pressure.

RESULTS Baseline HbA_1c was similar in the liraglutide and placebo group (8.8 ± 0.2 and 8.7 ± 0.1% [72.5 ± 2.2 and 71.8 ± 1.5 mmol/mol]). Change in HbA_1c from baseline was −0.6 ± 0.2% (−6.22 ± 1.71 mmol/mol) with liraglutide and −0.5 ± 0.2% (−5.56 ± 1.67 mmol/mol) with placebo (P = 0.62). Variation in glycemic excursions did not change in either group. Change in body weight was −3.13 ± 0.58 and +1.12 ± 0.42 kg (P < 0.0001) with liraglutide and placebo, respectively. The bolus insulin dose decreased in liraglutide-treated patients and did not change with placebo treatment (4.0 ± 1.3 vs. 0.0 ± 1.0 IU, P = 0.02). Heart rate increased within the liraglutide group (P = 0.04) but not compared with placebo, whereas mean systolic blood pressure decreased compared with placebo (between-group difference 3.21 mmHg [95% CI −8.31 to 1.90], P = 0.04). Liraglutide was more frequently associated with gastrointestinal adverse effects. The incidence of hypoglycemia did not differ between groups.

CONCLUSIONS Liraglutide significantly reduces body weight and insulin requirements but has no additional effect on HbA_1c in normal-weight patients with type 1 diabetes inadequately controlled on insulin alone.