Phase 1/2a, Randomized, Double-Blind, Placebo-Controlled, Study to Assess Safety, Tolerability, PK and PD Response of PB1023 Injection Following Single and Multiple SQ Doses in Adults With Type 2 Diabetes Mellitus

Inclusion Criteria: * Males or post menopausal or surgically sterile females age 18-75 years of age inclusive. * Diagnosed with T2DM for \> or = 6 months with HbA1c \> or = 6.0% but \< or = 9.0% while taking stable doses of one oral antihyperglycemic agent but \< or = 8.5% when taking two oral antihyperglycemic agents for up to a maximum of 3 months prior to screening. * Fasting Plasma glucose between 115 mg/dL and 269 mg/dL. * Fasting C-peptide of \> or = 0.8 ng/mL. * BMI \< or = 40 kg/m2. * Otherwise stable health except for T2DM. Exclusion Criteria: * Currently taking a non-oral antihyperglycemic agent. * Have taken a PPARg agonist within 90 days of screening. * Known allergy to an approved or investigational GLP-1 receptor analog/agonist. * Unstable cardiovascular disease as defined in clinical protocol. * History, symptoms or signs of pancreatitis or severe gastrointestinal disease. * Personal or family history of medullary thyroid tumors history of Multiple Endocrine Neoplasia Syndrome Type 2. * Poor glucose control as defined in clinical protocol. * Clinically significant renal and/or hepatic dysfunction as defined in clinical protocol. * Absolute requirement for corticosteroids or received systemic steroids within 90 days prior to PB1023 administration. * Pregnant or lactating females. * Known history or active alcohol or drug abuse within 12 months prior to screening. * Positive for HIV, Hepatitis B surface antigen or Hepatitis C antibodies. * Participating in any other study within 30 days prior to screening. * Other medical or psychiatric condition which in the opinion of the investigator would place the subject at increased risk.