OBJECTIVES: Exenatide and glargine are used for the treatment of type 2 diabetes (T2D) patients who are inadequately controlled on oral antidiabetic (OAD) medications.  This study examined concomitant medications (including “off- label” use), resource utilization, and mean HbA1C (A1C) reduction after initiation of exenatide compared to glargine.   METHODS: A retrospective claims analysis comprised of adult patients with T2D who initiated exenatide (N=9264) or glargine (N=3791) therapy between April 1, 2005 and June 30, 2007.  Concomitant medications and resource utilization were estimated using logistic regression with propensity score stratification used to control for baseline patient characteristics.  A subgroup analysis was performed in patients who had baseline and follow-up A1C data for exenatide (n=606) and glargine (n=251) to examine mean A1C reduction.  RESULTS: A higher percentage of exenatide-treated patients were using concomitant metformin only (21.4% vs. 10.7%, p<0.0001) and a lower percentage were using concomitant sulfonylurea only (3.2% vs. 6.4%, p=0.001).  There was no significant differences between percentage of patients using at least 1 OAD medication (89.2% vs. 88.9%, p=0.14) in both cohorts.  Exenatide-treated patients had 26% lower risk of hospitalizations (OR: 0.74, p<0.0001) mainly due to 38% lower risk of macrovascular complications (OR: 0.62, p<0.001).  Exenatide-treated patients also experienced 22% lower risk of hypoglycemic events (OR: 0.78, p=0.037).  A higher percentage of exenatide-treated patients with a baseline A1C ≥ 7% achieved an A1C goal of <7 (36.3% vs. 19.3%, p<0.001).  Exenatide-treated patients experienced a significantly greater mean reduction in A1C compared to glargine-treated patients after adjusting for baseline A1C (-0.80 vs. -0.52, p=0.0142).  CONCLUSIONS: Most patients were concomitantly using some OAD medications in both cohorts.  Exenatide-treated patients had a significantly lower risk of hospitalizations, macrovascular complications and hypoglycemic events.  In the patient subset with A1C data, exenatide-treated patients had a significantly greater reduction in mean A1C and higher percentage achieving goal than glargine-treated patients.