Safety and Efficacy of Exenatide Once Weekly Versus Liraglutide in Subjects With Type 2 Diabetes

Inclusion Criteria: * Diagnosed with type 2 diabetes * Have suboptimal glycemic control as evidenced by an HbA1c measurement at study start 7.1% and 11.0%, inclusive * Have a body mass index (BMI) ≤45 kg/m\^2 * Have been treated with lifestyle modification (diet and exercise) and with one of the following single oral antidiabetic agents (OADs) or combinations of OADs administered at maximum tolerated dose: * metformin * SU * metformin plus an SU * metformin plus pioglitazone Exclusion Criteria: * Have any contraindication, allergy, or hypersensitivity for the study drug (exenatide once weekly or liraglutide), exenatide twice daily, the OAD(s) being used, or the excipients contained in these agents * If taking metformin and have a contraindication to metformin use * Have been treated within 8 weeks of study start with systemic glucocorticoid therapy by oral, intravenous, intra-articular, or intramuscular route * Have been treated with drugs that promote weight loss (e.g., Xenical® \[orlistat\], Meridia® \[sibutramine\], Acomplia® \[rimonabant\], Acutrim® \[phenylpropanolamine\], or similar over-the-counter medications) within 3 months of study start * Have taken any of the following excluded medications for more than 1 week within the 3 months prior to study start, or have taken any of the following excluded medications within 1 month prior to study start: * Insulin * Alpha-glucosidase inhibitors (e.g., Glyser® \[miglitol\] or Precose® \[acarbose\]) * Meglitinides (e.g., Prandin® \[repaglinide\] or Starlix® \[nateglinide\]) * Avandia® (rosiglitazone) * Dipeptidyl peptidase (DPP)-4 inhibitors (e.g., Januvia™ \[sitagliptin\], Galvus® \[vildagliptin\], Onglyza™ \[saxagliptin\]) * Symlin® (pramlintide acetate) * Have donated blood within 30 days prior to study start or have had a blood transfusion or severe blood loss within 3 months prior to study start * Have at any time, including a clinical trial, taken exenatide once weekly, exenatide twice daily, liraglutide, or any other GLP-1 receptor agonist or GLP-1 analog * Are currently enrolled in, or discontinued within the last 3 months or longer if required by local guidelines, from a clinical trial involving use of an investigational drug or device, or concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study * Have previously been screen-failed from this study for any reason * If a subject discontinues metformin, sulfonylurea, or pioglitazone prior to screening, the subject can be included if they discontinued the medication (whether alone or as component of combined medication) according to a specific schedule.