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Completed

NCT Number: NCT01726764

Interaction Between St John's Wort and Metformin?

The goal of the study is to examine the difference of the pharmacokinetics of metformin with and without a 3 weeks pretreatment of St John's Wort. Furthermore secondary objectives include changes in GLP-1, C-peptide, serum-insulin and plasma-glucose during an oral glucose tolerance test, changes in OCT1 mRNA in plasma and changes in leptin and lipid-profile following this possible interaction.

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Key information

Conditions

Type 2 Diabetes Behavior Behavioral Symptoms Depression Diabetes Mellitus Diabetes Mellitus, Type 2 Endocrine System Diseases Glucose Metabolism Disorders Metabolic Diseases Nutritional and Metabolic Diseases

Age range

18 year–64 year

Sex eligibility

Male

Study type

Interventional

Phase

Phase 1

Primary location

Department of Clinical Pharmacology, Institute of Public Health, University of Southern Denmark

Odense, DK-5000, Denmark

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Men aged 18-64 years
  • Homozygous for common genetic variants in the genes organic cation transporter 1/2 (OCT1/OCT2)
  • Normal values of biomarkers accounting for: Liver and kidney function, and normal blood glucose

Exclusion criteria

  • Chronic alcohol abuse
  • Hypersensitivity to metformin or St John's Wort
  • Daily intake of drugs requiring prescription

Treatment and study plan

St John's Wort

Other

metformin

Drug

Primary outcomes

  1. Change in Area Under Curve (AUC) 0-24h of metformin

    Time frame: Concentration of metformin at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24 hours after metformin ingestion

    Change in 0-24h AUC of metformin after 3 weeks of treatment with St John's Wort

Secondary outcomes

  1. Oral glucose tolerance test (OGTT)

    Time frame: During the first 2 hours of each metformin ingestion

    Changes in: Plasma-glucose, serum-insulin, glucagon-like peptide 1 (GLP-1) and connecting-peptides (C-peptides) during the oral glucose tolerance test, measured at 0, 0.5, 1, 1.5 and 2 hours after metformin ingestion.

  2. Pharmacokinetics of metformin

    Time frame: Concentration of metformin at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 12, 24 hours after metformin ingestion, which will be used to determine the pharmacokinetic parameters mentioned below

    Determination of other pharmacokinetic parameters of metformin such as clearance (CL), absorption fraction (F), distribution volume (V), the minimum concentration at steady state (Css,min), elimination half life (T 1/2) etc.

  3. Change in messenger RiboNucleic Acid (mRNA)

    Time frame: Will be measured 4 times: At inclusion (t=0 on that day), at t=0 in both periods and minimum 3 weeks after finalization of the study (t=0 on that day)

    Changes in mRNA encoding OCT1 will be measured at 4 different time points to give an insight to the importance of St John's Wort effect on the OCT1 production

Other outcomes

  1. Hypericin/hyperforin

    Time frame: At t=0 in 2nd period

    If possible measure the concentrations of some of the active components of St John's Wort, hypericin and hyperforin

Sponsors and collaborators

Lead sponsor

University of Southern Denmark

Other

Registry information

Official study title

Is There a Pharmacokinetic Interaction Between St John's Wort and Metformin?

Important dates

Study start
2013
Primary completion
2013
Study completion
2014
First posted
Nov 15, 2012
Registry last updated
Dec 3, 2014

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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