Efficacy and Safety of LixiLan, a Titratable Fixed-Ratio Combination of Lixisenatide and Insulin Glargine, Versus Insulin Glargine in Type 2 Diabetes Inadequately Controlled on Metformin Monotherapy: The LixiLan Proof-of-Concept Randomized Trial

OBJECTIVE This study assessed the efficacy and safety of LixiLan, a fixed-ratio, titratable, combination of 2 units insulin glargine (Gla-100) and 1 μg lixisenatide administered once daily via a single pen, versus Gla-100 in insulin-naïve type 2 diabetes on metformin. RESEARCH DESIGN AND METHODS Participants were randomized to once-daily LixiLan (n = 161) or Gla-100 (n = 162) for 24 weeks, while continuing metformin. LixiLan and Gla-100 were started at 10 units/5 μg and 10 units, respectively, and titrated based on the Gla-100 requirement according to fasting plasma glucose levels. The primary objective was to test noninferiority (upper bound of the 95% CI ≤0.4%) of LixiLan in reducing HbA1c; if met, statistical superiority was tested. Secondary objectives included body weight changes, hypoglycemia, and safety. RESULTS Baseline characteristics (mean age 57 years, diabetes duration 6–7 years, BMI 32 kg/m2) were similar between groups. At week 24, mean HbA1c was reduced from 8.0% (64 mmol/mol) at baseline to 6.3% (45 mmol/mol) and 6.5% (48 mmol/mol) with LixiLan and Gla-100, respectively, establishing statistical noninferiority and superiority of LixiLan (least-squared mean [95% CI] difference: −0.17% [−0.31, −0.04] {−1.9 mmol/mol [−3.4, −0.4]}; P = 0.01). HbA1c <7.0% (<53 mmol/mol) was achieved in 84% and 78% of participants (nonsignificant), respectively. LixiLan improved 2-h postmeal plasma glucose versus Gla-100 (least-squared mean difference: –3.17 mmol/L [–57 mg/dL]; P < 0.0001). Body weight was reduced with LixiLan (–1 kg) and increased with Gla-100 (+0.5 kg; P < 0.0001), with no increase in hypoglycemic events (∼25% in each group). The incidence of nausea (7.5%) and vomiting (2.5%) was low with LixiLan. CONCLUSIONS LixiLan achieved statistically significant reductions to near-normal HbA1c levels with weight loss and no increased hypoglycemic risk, compared with insulin glargine alone, and a low incidence of gastrointestinal adverse events in type 2 diabetes inadequately controlled on metformin.