BACKGROUND: In the parent study of this analysis, patients with type 2 diabetes received lixisenatide before breakfast or the main meal of the day. This substudy was designed to examine the effect of lixisenatide administered before breakfast or the main meal of the day on continuously assessed 24-hour patient glucose profiles. METHODS: A subset of patients from the parent study underwent 2 14-day periods of continuous glucose monitoring (CGM) at the start and end of the 24-week study. Ambulatory glucose profile analysis was used to measure changes over time in detailed aspects of the glucose profiles. The breakfast group consumed a standardized meal during both CGM periods to determine change in 4-hour glycemic response. RESULTS: Data were available for 69 patients in the substudy, 40 from the original breakfast group and 29 from the main meal group. Between baseline and end of study, mean (standard deviation) total glucose exposure decreased from 4198.1 (652.3) to 3681.2 (699.6) mg/dL*24 h in the breakfast group (P < .0001) and from 4127.9 (876.8) to 3880.9 (1165.0) mg/dL*24 h in the main meal group (P = .0224). For patients included in the substudy, HbA1c decreased by approximately 0.6% in both groups. Mean (standard deviation) 4-hour total glucose exposure fell by 168.9 (158.4) mg/dL*4 h (P < .0001) from baseline. CONCLUSIONS: This analysis demonstrates that lixisenatide has beneficial effects on components of the 24-hour glucose profile, which endure beyond the meal at which it is administered. Continuous glucose monitoring analysis detects changes not captured using HbA1c alone.