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Metformin-Dipyridamole Interaction Trial (MetDipy)

This study has been completed.
Information provided by (Responsible Party):
Radboud University Identifier:
First received: May 25, 2012
Last updated: April 26, 2013
Last verified: March 2012
The antihyperglycemic drug metformin and the thrombocyte aggregation inhibitor dipyridamole are often used concomitantly in patients with diabetes who have suffered a transient ischemic attack or stroke. It has recently been suggested that the gastrointestinal absorption of metformin is mediated by the equilibrative nucleoside transporter 4 (hENT4). Dipyridamole has been reported to inhibit hENT4 transport in vitro. The aim of this research proposal is to study the pharmacokinetic interaction between metformin and dipyridamole. The investigators hypothesize that dipyridamole reduces the gastrointestinal absorption of metformin. If this hypothesis can be confirmed, then the results of this study can explain in part the high variability in plasma metformin concentrations in patients treated with diabetes, and can be used to optimize pharmacotherapy in patients with diabetes.

Condition Intervention Phase
Diabetes Drug: Metformin, dipyridamole Drug: Metformin Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Official Title: The Effect of Dipyridamole on the Pharmacokinetics of Metformin

Resource links provided by NLM:

Further study details as provided by Radboud University:

Primary Outcome Measures:
  • The area under the curve of the metformin plasma concentration at several timepoints [ Time Frame: 10 hours after ingestion of last dose of metformin ]
    The area under the curve of the metformin plasma concentration at t=0, t=1, t=2, t=2.5, t=3, t=3.5, t=4, t=5, t=6, t=8, and t=10 hours after the intake and the Cmax.

  • Peak plasma concentration (Cmax) of metformin [ Time Frame: about 3 hours after intake of last dose of metformin ]
    Peak plasma concentration (Cmax) of metformin

Enrollment: 18
Study Start Date: April 2012
Study Completion Date: July 2012
Primary Completion Date: July 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Metformin therapy with concomitant use of dipyridamole
Metformin 500 mg twice daily for four days in combination with dipyridamole 200 mg twice daily for four days
Drug: Metformin, dipyridamole
Metformin 500 mg twice daily for four days Dipyridamole 200 mg twice daily for four days
Active Comparator: Metformin therapy
Metformin 500 mg twice daily for four days
Drug: Metformin
Metformin 500 mg twice daily for four days


Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Age 18-50 years
  • Written informed consent

Exclusion Criteria:

  • Smoking
  • Hypertension (systolic blood pressure > 140 mmHg and/or diastolic blood pressure > 90 mmHg)
  • Diabetes Mellitus (fasting glucose >7.0 mmol/L or random glucose >11 mmol/L)
  • History of any cardiovascular disease
  • Concomitant use of medication
  • Renal dysfunction (MDRD <60 ml/min)
  • ECG abnormalities, other than firs grade AV-block or right bundle branch block
  Contacts and Locations
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Please refer to this study by its identifier: NCT01613755

Radboud University Nijmegen Medical Centre
Nijmegen, Gelderland, Netherlands, 6500 HB
Sponsors and Collaborators
Radboud University
Principal Investigator: N. Riksen, MD, PhD Radboud University
Principal Investigator: G. Rongen, MD, PhD Radboud University
  More Information

Responsible Party: Radboud University Identifier: NCT01613755     History of Changes
Other Study ID Numbers: Met-Dipy001
Study First Received: May 25, 2012
Last Updated: April 26, 2013

Keywords provided by Radboud University:
Effect Dipyridamole on pharmacokinetics of metformin

Additional relevant MeSH terms:
Hypoglycemic Agents
Physiological Effects of Drugs
Phosphodiesterase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Vasodilator Agents processed this record on September 21, 2017