Lilly's decision to cancel this trial is due to regulatory uncertainty in China.

The main purpose of this study is to compare the efficacy and safety of a new basal insulin, insulin peglispro, to insulin glargine in participants with type 2 diabetes mellitus (T2DM). Both drugs will be given by an injection under the skin. Participants may continue to take oral antihyperglycemic medication (OAM) during the study, as prescribed by their personal physician. The study is expected to last about 12 months for each participant.

Inclusion Criteria:

• Have T2DM (per World Health Organization [WHO] Classification of Diabetes) not treated with insulin.
• Have had diabetes for at least 1 year.
• Have been receiving at least 2 oral antihyperglycemic medications (OAMs) for at least 3 months prior to the study.
• Have hemoglobin A1c (HbA1c) of 7.0% to 11.0%, inclusive, according to central lab at screening.
• Have body mass index (BMI) ≤40 kilogram/square meter (kg/m^2).
• This inclusion criterion applies to females of child-bearing potential (not surgically sterilized and between menarche and 1-year postmenopausal) only: are not breastfeeding, test negative for a serum pregnancy test, intend not to become pregnant during study or willing to have a reliable method of birth control.

Exclusion Criteria:

• Insulin therapy: have used insulin therapy (outside of pregnancy) anytime in the past 2 years, except for short-term treatment of acute conditions, and up to a maximum of 4 continuous weeks. Insulin use of any duration during pregnancy is not considered an exclusion criterion.

• Concomitant medications: rosiglitazone, pramlintide, glucagon-like peptide-1 (GLP-1) receptor agonist (for example, exenatide, exenatide once weekly, or liraglutide) used concurrently or within 3 months prior to screening.

• Local OAM restrictions: for participants on OAMs, restrictions for cardiac, renal, hepatic diseases and maximum dose, local product regulations must apply.

• Weight loss medications: are currently taking, or have taken within the 3 months preceding screening, prescription or over-the-counter medications to promote weight loss.

• Severe hypoglycemia history: have had any episodes of severe hypoglycemia within 6 months prior to screening.

• Diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar nonketotic coma (HHNKC): have had 1 or more episodes of DKA or hyperosmolar state/coma in the past 6 months.

• Cardiovascular: have cardiac disease with functional status that is New York Heart Association Class III or IV (per New York Heart Association [NYHA] Cardiac Disease Classification).

• Renal: have a history of renal transplantation, or are currently receiving renal dialysis or have serum creatinine ≥2 milligram/deciliter (mg/dL) (177 micromole/liter [mol/L]).

• Hepatic: have obvious clinical signs or symptoms of liver disease (excluding non-alcoholic fatty liver disease [NAFLD]), acute or chronic hepatitis, non-alcoholic steatohepatitis (NASH), or elevated liver enzyme measurements.

• Lipid-lowering medications:

  • Are using niacin preparations as a lipid-lowering medication or bile acid sequestrants within 90 days prior to screening; or,
  • Are using lipid-lowering medication at a dose that has not been stable for ≥90 days prior to screening.