A Study to Assess Cardiovascular Outcomes Following Treatment With MK-3102 in Participants With Type 2 Diabetes Mellitus (MK-3102-018)

• Time to first event in the cardiovascular (CV) composite endpoint of CV-related death, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina requiring hospitalization [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: Yes ]
• Change from baseline in hemoglobin A1C (A1C) at Week 18 in a sub-study of participants taking insulin (with or without metformin) [ Time Frame: Baseline and Week 18 ] [ Designated as safety issue: No ]
• Percentage of participants who experienced at least one adverse event in a sub-study of participants taking insulin (with or without metformin) [ Time Frame: Up to Week 18 ] [ Designated as safety issue: Yes ]
• Percentage of participants who discontinued from study drug due to an adverse event in a sub-study of participants taking insulin (with or without metformin) [ Time Frame: Up to Week 18 ] [ Designated as safety issue: Yes ]

• Time to first composite CV endpoint of confirmed CV-related death, nonfatal MI, and nonfatal stroke [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to first event for each of the individual CV endpoints: confirmed CV-related death, MI (fatal + nonfatal), stroke (fatal + nonfatal), and unstable angina requiring hospitalization [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to all-cause mortality [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: Yes ]
• Change from baseline in A1C at Week 156 [ Time Frame: Baseline and Week 156 ] [ Designated as safety issue: No ]
• Change from baseline in fasting plasma glucose (FPG) at Week 156 [ Time Frame: Baseline and Week 156 ] [ Designated as safety issue: No ]
• Percentage of participants achieving a target A1C <7.0 % (53 mmol/mol) by Week 156 [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: No ]
• Time to initiation of long-term insulin therapy (long-term insulin therapy is defined as a continuous period of insulin use of more than 3 months) in participants not receiving insulin at baseline [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: No ]
• Change from baseline in FPG at Week 18 in a sub-study of participants taking insulin (with or without metformin) [ Time Frame: Baseline and Week 18 ] [ Designated as safety issue: No ]
• Percentage of participants achieving a target A1C <7.0 % (53 mmol/mol) by Week 18 in a sub-study of participants taking insulin (with or without metformin) [ Time Frame: Up to 18 weeks ] [ Designated as safety issue: No ]
• Percentage of participants who experienced at least one adverse event [ Time Frame: Up to 159 weeks ] [ Designated as safety issue: Yes ]
• Percentage of participants who discontinued from study drug due to an adverse event [ Time Frame: Up to 156 weeks ] [ Designated as safety issue: Yes ]

• Time to first major adverse cardiac event (CV-related death, nonfatal myocardial infarction, and nonfatal stroke) [ Time Frame: up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to CV-related death [ Time Frame: up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to nonfatal myocardial infarction [ Time Frame: up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to nonfatal stroke [ Time Frame: up to 156 weeks ] [ Designated as safety issue: Yes ]
• Time to unstable angina requiring hospitalization [ Time Frame: up to 156 weeks ] [ Designated as safety issue: Yes ]

The purpose of this study is to evaluate the cardiovascular (CV) safety profile of MK-3102 in participants with type 2 diabetes mellitus (T2DM). The primary hypothesis is that treatment with MK-3102 25 mg once weekly is non-inferior to treatment with placebo and active comparators across the MK-3102 program with regard to the risk of developing a confirmed event in the primary CV composite endpoint.

• Drug: MK-3102
• Drug: Placebo

• Experimental: MK-3102
  MK-3102 25 mg capsule administered orally once weekly
  Intervention: Drug: MK-3102
• Placebo Comparator: Placebo
  Matching placebo to MK-3102 capsule administered orally once weekly
  Intervention: Drug: Placebo

Inclusion Criteria:

• Diagnosed with type 2 diabetes mellitus

• Is on one of the following diabetes treatment regimens that is stable for at least 12 weeks (except for pioglitazone for at least 16 weeks) and is within the associated A1C range for that treatment regimen:

  1. A1C >= 6.5% and <= 10.0% (>=48 mmol/mol and <=86 mmol/mol) on: (a) diet or exercise alone (not on antihyperglycemic agent [AHA] for >= 12 weeks) OR (b) monotherapy with metformin (MF), pioglitazone (PIO) or an alpha-glucosidase inhibitor (AGI) or a sodium-glucose cotransporter inhibitor (SGLT2i) OR (c) dual combination therapy with MF, PIO, AGI or SGLT2i OR
  2. A1C >= 7.0% and <=10.0% (>=53 mmol/mol and <=86 mmol/mol) on (a) monotherapy with a sulfonylurea or meglitinide OR (b) dual combination therapy with a sulfonylurea or a meglitinide and MF, PIO, AGI, or SGLT2i OR
  3. A1C >=7.0% and <=10.0% (>=53 mmol/mol and <=86 mmol/mol) on one of the following insulin regimens (with or without metformin): (a) basal insulin (e.g.; insulin glargine, insulin detemir, NPH insulin, degludec) OR (b) prandial insulin (e.g. regular, aspart, lispro, glulisine) OR (c) basal/prandial insulin regimen consisting of multiple dose insulin injections of basal and prandial insulin or the use of pre-mixed insulin (e.g., Novolog 70/30®, Novolin 70/30®, Humalog 75/25®, or Humulin 70/30®
• Pre-existing vascular disease (coronary artery disease, ischemic cerebrovascular disease, atherosclerotic peripheral artery disease)
• (1) Male; (2) female not of reproductive potential; or (3) female of reproductive potential who agrees to remain abstinent or use alone or in conjunction with their partner 2 methods of contraception to prevent pregnancy during the study and for 21 days after the last dose of study drug.

Exclusion Criteria:

• History of type 1 diabetes mellitus or a history of ketoacidosis
• Treated with rosiglitazone, a dipeptidyl peptidase-IV (DPP-4) inhibitor, or a glucagon-like peptide-1 (GLP-1) receptor agonist within 12 weeks prior to study participation or previously treated with MK-3102
• On a weight loss program and is not in the maintenance phase or has been on a weight loss medication in the past 6 months or has undergone bariatric surgery within 12 months prior to study participation
• Medical history of active liver disease (other than non-alcoholic hepatic steatosis), including chronic active hepatitis B or C, primary biliary cirrhosis, or symptomatic gallbladder disease
• Human immunodeficiency virus (HIV) as assessed by medical history
• New or worsening coronary heart disease, congestive heart failure, myocardial infarction, unstable angina, coronary artery intervention, stroke, or transient ischemic neurological disorder within the past 3 months
• History of malignancy <=5 years prior to study participation, except for adequately treated basal cell or squamous cell skin cancer, or in situ cervical cancer
• Clinically important hematological disorder (such as aplastic anemia, myeloproliferative or myelodysplastic syndromes, thrombocytopenia)
• Pregnant or breast feeding, or is expecting to conceive or donate eggs during the trial, including 21 days following the last dose of study drug