BACKGROUND: A few Randomized Controlled Trials (RCTs) have evaluated the use of 
liraglutide in Type 1 Diabetes (T1D). Through the present systematic review and 
meta-analysis, we aim at critically appraising and summarizing those RCTs, 
providing precise effect estimates.
METHODS: We searched major databases and grey literature from their inception to 
October 2018, for RCTs with a duration ≥ 12 weeks, comparing liraglutide with 
placebo or any other comparator as adjunct to insulin in patients with T1D, 
investigating major efficacy and safety endpoints. This review is reported in 
accordance with the Preferred Reporting Items for Systematic reviews and 
Meta-Analyses (PRISMA) statement.
RESULTS: We included 5 trials with 2,445 randomized participants. Liraglutide 
provided modest reductions in HbA1c, with liraglutide 1.8 mg producing the 
greatest decrease (MD = -0.24%, 95% CI -0.32 to -0.16, I2=0%). Significant 
weight reduction, up to 4.87 kg with liraglutide 1.8 mg was also observed (95% 
CI -5.31 to -4.43, I2=0%). Decrease in total daily insulin dose, primarily 
driven by a decrease in bolus insulin requirements, was demonstrated. 
Liraglutide decreased non-significantly the odds for severe hypoglycemia 
(OR=0.80, 95% CI 0.57-1.14, I2=0%), while it increased significantly the odds 
for gastrointestinal adverse events (for nausea, OR=4.70, 95% CI 3.68-6.00, 
I2=37%, and for vomiting, OR=2.50, 95% CI 1.54-4.72, I2=27%). A significant 
increase in heart rate was also demonstrated. No association with diabetic 
ketoacidosis or malignancies was identified.
CONCLUSION: In patients with T1D, liraglutide might prove be an adjunct to 
insulin, improving glycemic control, inducing body weight loss and decreasing 
exogenous insulin requirements and severe hypoglycemia.