Project Summary

This research project is in progress. PCORI will post the research findings on this page within 90 days after the results are final.

PCORI has identified second-line treatment of type 2 diabetes as an important research topic. Second-line treatment is given when the initial treatment does not work or stops working. Patients, caregivers, clinicians, and others want to learn: How do second-line medicines compare to each other for treating type 2 diabetes when metformin is no longer effective? To help answer this question, PCORI launched an initiative in 2020 on Observational Analyses of Second-Line Pharmacological Agents in Type 2 Diabetes. The initiative funded this research project.

What is the research about?

Type 2 diabetes is a long-term illness that causes blood sugar levels to rise. Patients with type 2 diabetes are at increased risk for heart disease. Keeping blood sugar levels normal may help prevent heart problems among people with diabetes.

To treat diabetes, doctors often start with a medicine called metformin. If patients taking metformin continue to have high blood sugar levels, doctors can use another class of medicine. A medicine class is a group of medicines that share certain similarities. For example, medicines within the same class may cause similar changes in the body or have a similar chemical structure. Questions remain about how well different classes of medicine work to prevent heart problems from diabetes.

In this study, the research team is comparing four classes of diabetes medicines for preventing health problems among patients at risk for heart disease. The team is also looking at how well the medicines work for health outcomes that are most important to patients. Finally, the team is comparing how well specific medicines within each medicine class work.

Who can this research help?

Results may help patients at risk for heart disease and their doctors when choosing medicines to treat type 2 diabetes.

What is the research team doing?

This study has three parts. In the first part, the research team is using insurance claims data from adults with type 2 diabetes who are at moderate risk for heart disease. With these data, the team is comparing clinical outcomes such as heart attacks, stroke, and death among patients taking the four classes of medicine.

In the second part, the research team is interviewing patients with type 2 diabetes who are receiving care at one of two health systems. The team is asking patients what health outcomes matter to them and then asking them to rank those outcomes. Then, the team is using the claims data to compare the effects of the four classes of medicine on the outcomes that patients rated as most important.

Finally, the research team is comparing how well specific medicines within each class work to improve clinical outcomes and the outcomes patients rated as most important.

Patients with type 2 diabetes, doctors, a pharmacist, a diabetes educator, and staff from the American Diabetes Association are helping to plan and conduct the study.

Research methods at a glance

Design Element Description
Design Observational: cohort study

Claims data: More than 700,000 adults ages 21 and older with type 2 diabetes who were at moderate risk for cardiovascular disease and who were treated with one or more of four classes of medicine of interest: glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors, dipeptidyl peptidase-4 inhibitors, and sulfonylurea medicines

Interviews: 40 adults with type 2 diabetes who were treated with one or more of four classes of medicine of interest at one of two health systems
  • Glucagon-like peptide-1 receptor agonists
  • Sodium-glucose cotransporter 2 inhibitors
  • Dipeptidyl peptidase-4 inhibitors
  • Sulfonylureas

Primary: composite measure of major adverse cardiovascular events including non-fatal myocardial infarction, non-fatal stroke, and death from any cause

Secondary: non-fatal myocardial infarction, non-fatal stroke, death from any cause, hospitalization for heart failure, revascularization procedure events, lower extremity complications, microvascular complications, kidney disease, dialysis initiation, blindness, treatment for diabetic eye disease, severe hypoglycemia, severe genitourinary tract infections, all-cause hospitalizations, and outcomes that were important to patients

Timeframe Timeframe Length of follow-up for collecting data on primary outcomes. View Glossary Up to 7-year follow-up for primary outcomes

Project Information

Rozalina McCoy, MD, MS
Mayo Clinic
Second-Line Therapies for Patients with Type 2 Diabetes and Moderate Cardiovascular Disease Risk

Key Dates

March 2021
August 2025


Award Type
Health Conditions Health Conditions These are the broad terms we use to categorize our funded research studies; specific diseases or conditions are included within the appropriate larger category. Note: not all of our funded projects focus on a single disease or condition; some touch on multiple diseases or conditions, research methods, or broader health system interventions. Such projects won’t be listed by a primary disease/condition and so won’t appear if you use this filter tool to find them. View Glossary
Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
State State The state where the project originates, or where the primary institution or organization is located. View Glossary
Last updated: September 26, 2023