A Preliminary Study of the Efficacy and Safety of MK-8521 for Type 2 Diabetes (MK-8521-004)

Inclusion Criteria:

- Have T2DM in accordance with American Diabetes Association guidelines

- Be on metformin monotherapy (>-1000 mg/day: metformin IR or metformin XR) for at
least 12 weeks prior to study start with a hemoglobin A1C (A1C) >-7.5 and <-10.5% OR
Be on dual therapy with metformin (>-1000 mg/day: dose stable for at least 4 weeks
prior to study start) with an A1C of >-7.0% and <-10.0% and a second AHA and be
willing to washout the second AHA. Allowable AHAs are dipeptidyl peptidase 4 (DPP-4
inhibitors), alpha-glucosidase inhibitors, sulfonylureas, and glinides.

- Have a body mass index (BMI) ≥23 kg/m2 and ≤40 kg/m2

- Is a female who is not of reproductive potential, or is a female of reproductive
potential who agrees to avoid becoming pregnant: while receiving study drug and for
14 days after the last dose of study drug

Exclusion Criteria:

- Have a history of type 1 diabetes or a history of diabetic ketoacidosis

- Has a history of other specific types of diabetes (e.g., genetic syndromes, secondary
pancreatic diabetes, diabetes due to endocrinopathies, drug- or chemical-induced, and
post-organ transplant)

- Has been treated with any gut-derived incretin hormone glucagon-like peptide 1
(GLP-1) receptor agonist (e.g. Byetta™, Victoza™ or investigational agents) within
the last 6 months or has had GLP-1 receptor agonist discontinued due to
gastrointestinal intolerance or lack of efficacy. Note: treatment with a GLP-1
receptor agonist that was discontinued >6 months prior to study start is not an
exclusion if the GLP-1 receptor agonist was discontinued for reasons other than
gastrointestinal intolerance or lack of efficacy.

- Has a history of clinically significant gastrointestinal disorder (including diabetic
gastroparesis; irritable bowel disease; recurrent episodes of nausea, vomiting,
diarrhea and abdominal pain)

- Has a history of clinically significant and active, immunological, respiratory,
genitourinary or major neurological (including stroke, transient ischemic attack and
chronic seizures) abnormalities or diseases

- Has a history of cardiovascular disease (including diabetic cardiomyopathy) or
significant cardiac condition (including a history of myocardial infarction, stable
or unstable angina, arterial revascularization, pathologic, symptomatic or sustained
tachyarrhythmia [e.g. atrial fibrillation, sustained supraventricular tachycardia,
symptomatic non-sustained supraventricular tachycardia, ventricular tachycardia,
ventricular fibrillation, Wolf-Parkinson-White syndrome, congenital long QT syndrome,
etc.]) or heart failure

- Has a family history of medullary carcinoma of the thyroid or multiple endocrine
neoplasm type-2 syndrome

- Has active diabetic proliferative retinopathy or a history of maculopathy

- Has human immunodeficiency virus (HIV)

- Has a medical history of active liver disease (other than non-alcoholic hepatic
steatosis), including chronic hepatitis B or C (assessed by medical history), primary
biliary cirrhosis, or active symptomatic gallbladder disease

- Is on a weight loss medication or has undergone bariatric surgery

- Has a history of acute or chronic pancreatitis of any etiology

- Had an event of severe hypoglycemia with neuroglycopenia in the past 12 months

- Has a positive urine pregnancy test

- Is pregnant or breast-feeding, or is planning to conceive during the trial, including
14 days following the last dose of investigational product

- Routinely consumes >1 alcoholic drinks per day or >7 alcoholic drinks per week or
engages in binge drinking

- Routinely consumes ≥480mg /day caffeine in caffeinated beverages (1 cup of coffee
contains approximately 120 mg of caffeine

- Is taking a beta blocker or medications with sympathomimetic activity (e.g.
pseudoephedrine, phenylpropanolamine, etc.)

- Is currently a user of nicotine or nicotine containing products or does not agree to
refrain from using nicotine during the trial, including 14 days following the last
dose of investigational product

- Is currently a user of any illicit drugs (including any marijuana use) or has a
history of drug (including alcohol) abuse within approximately 5 years

- has other severe acute or chronic medical or psychiatric condition or laboratory
abnormality that may increase the risk associated with study participation or blinded
investigational product administration