This is a Phase 1 study, involving a 10-day dosing period, designed to test the safety of investigational study drug ARRY-403 (as monotherapy or in addition to stable metformin therapy) in patients with Type 2 diabetes. Approximately 128 patients from the US will be enrolled in this study.

Key Inclusion Criteria:

• Male or female (females must be of non-childbearing potential), between the ages of 18 and 70 years, inclusive.
• Diagnosis of Type 2 diabetes.
• Fasted C-peptide value ≥ 0.8 ng/mL.
• HbA1c ≥ 6.5% and ≤ 10.0% for monotherapy cohorts (study drug only) or HbA1c ≥ 7.5% and ≤ 10.0% for combination cohorts (study drug and on a stable regimen of metformin monotherapy that includes a morning dose for ≥ 8 weeks prior to first dose of study drug).
• BMI ≥ 25.0 kg/m2 and ≤ 40.0 kg/m2
• Additional criteria exist.

Key Exclusion Criteria:

• Recent history (i.e. less than 6 months) or concomitant/ongoing clinically significant hematologic, renal, pulmonary, gastrointestinal, hepatic, psychiatric, neurologic, dermatologic or allergic disease (including drug allergies that are clinically significant and not remote, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing), or other conditions at the discretion of the investigator.
• Significant cardiac disease, myocardial infarction within 6 months of study start, unstable angina, congestive heart failure, known arrhythmias of ventricular etiology, unexplained syncope or syncope/seizures related to arrhythmia.
• History of gastric surgery, vagotomy, bowel resection or any surgical procedure that might interfere with gastrointestinal motility, pH, or absorption.
• A positive test for drugs or alcohol.
• Active infectious diseases including hepatitis B, hepatitis C, or human immunodeficiency virus (HIV). Past history and inactive hepatitis B and C, as confirmed by serological testing, are allowed.
• Women who are pregnant or breastfeeding.
• Donation or loss of ≥ 550 mL of blood (including plasmapheresis) or receipt of a transfusion of any blood product within 8 weeks prior to first dose of study drug.
• Additional criteria exist.