Background: Liraglutide may be less effective in patients with more advanced type 2 diabetes. This study from the Association of British Clinical Diabetologists Nationwide Liraglutide Audit analysed changes in HbA1c of patients after 26 weeks of treatment with liraglutide 1.2 mg, stratified according to the intensity of their background diabetes therapy, or according to their duration of diabetes. Methods: Patients using liraglutide as add-on therapy were stratified for receipt to one, two or three oral antidiabetic agents (OADs) or insulin (± OAD), or for diabetes duration of 0-5 years, 6-10 years, or >10 years. Changes in HbA1c were compared across groups after adjusting for baseline HbA1c. Results: After exclusions to standardise comparisons, 937 patients with background diabetes treatment and 802 patients with recorded diabetes duration were analysed. Least-squares adjusted mean changes in HbA1c (± SEM) were-1.8% ± 0.1 for 135 patients on one OAD,-1.7% ± 0.1 for 284 patients on two OADs,-1.9% ± 0.1 for 94 patients on three OADs (n=94) and-1.0% ± 0.1 for 424 patients receiving insulin. HbA1c changes did not differ significantly between OAD groups, but all OAD groups had greater HbA1c reductions compared with the insulin group (all p10 years (n=399). Conclusion: The need for insulin and long diabetes duration, but not the number of OADs taken, predicted a smaller treatment response to liraglutide.