Using metformin to prevent heart problems in patients with prediabetes after a heart attack

The Myocardial Infarction and New Treatment With Metformin Study (MIMET) - a R-RCT to Study Metformin and the Prevention of Cardiovascular Events in Patients With Acute Myocardial Infarction and Newly Detected Prediabetes

Phase 3 Interventional Karolinska Institutet · NCT05182970

This study is testing if adding metformin to regular care can help prevent heart problems in people with prediabetes who have just had a heart attack.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment5160 (estimated)
Ages18 Years to 80 Years
SexAll
SponsorKarolinska Institutet Academic / other
Locations1 site (Ljungby)
Trial IDNCT05182970 on ClinicalTrials.gov

What this trial studies

This study investigates the effects of adding metformin to standard care in patients who have experienced an acute myocardial infarction and have newly diagnosed prediabetes. It is a national multicenter randomized controlled trial where participants will be assigned to receive either standard care alone or standard care plus metformin. The study aims to evaluate the impact of this intervention on the occurrence of major cardiovascular events over a follow-up period of 24 months. Data will be collected from the SWEDEHEART registry and patients will be monitored for various cardiovascular outcomes.

Who should consider this trial

Good fit: Ideal candidates are Swedish citizens aged 18 to 80 who have experienced an acute myocardial infarction and have newly diagnosed prediabetes.

Not a fit: Patients with type 1 diabetes, known type 2 diabetes, or those requiring glucose-lowering treatment may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved cardiovascular outcomes for patients with prediabetes following a heart attack.

How similar studies have performed: Other studies have suggested potential benefits of metformin in cardiovascular outcomes, but this specific approach is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

I. AMI

II. Swedish citizens with a personal ID number ≥18 years and ≤80 years

III. Newly diagnosed prediabetes:

1. HbA1c 42-47 mmol/mol or
2. Capillary or venous fasting plasma glucose concentration 6.1-6.9 mmol/L or
3. 2-hour post-load capillary glucose concentration 8.9-12.1 mmol/L or
4. 2-h post-load venous plasma glucose concentration 7.8-11.0 mmol/L
5. HbA1c \<48 mmol/mol and 2-hour post-load capillary glucose concentration \>12.1 mmol/L or 2-h post-load venous plasma glucose concentration \>11.0 mmol/L (thus elevated 2-hour glucose levels in the diabetes range but without HbA1c levels diagnostic for diabetes)

IV. Naïve to metformin and other glucose lowering therapy

V. Signed informed consent

Exclusion Criteria:

I. Type 1 diabetes

II. Known type 2 diabetes

III. Indication for glucose lowering treatment

IV. Acute condition with high risk for volume depletion, circulatory shock, hypoxia

V. Serious illness, other than cardiovascular, with short life expectancy

VI. Renal failure (eGFR \<60ml/min)

VII. Hepatic failure

VIII. Malignancy within the last year

IX. Contraindication or hypersensitivity to the study drug

X. Alcohol or drug abuse

XI. Pregnancy or breastfeeding

XII. Women of childbearing potential without adequate anticonception during any part of the study period

XIII. Previous hospitalisation for lactic acidosis

XIV. Predicted inability to comply with the study protocol

Where this trial is running

Ljungby

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions PreDiabetesAcute Myocardial InfarctionNon ST Elevation Myocardial InfarctionST Elevation Myocardial Infarction
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.