Effects of St. John's Wort on the Oral Contraceptive Hormone Levonorgestrel (R21 AT002297)

This study has been completed.
Sponsor:
Collaborator:
Information provided by:
University of Utah
ClinicalTrials.gov Identifier:
NCT00131885
First received: August 17, 2005
Last updated: August 10, 2011
Last verified: August 2011
Results First Received: March 21, 2010  
Study Type: Interventional
Study Design: Allocation: Randomized;   Endpoint Classification: Pharmacokinetics/Dynamics Study;   Intervention Model: Parallel Assignment;   Masking: Single Blind (Subject);   Primary Purpose: Treatment
Condition: Contraception
Interventions: Dietary Supplement: Placebo Control (Placebo Herb)
Dietary Supplement: St. John's Wort
Drug: Levonorgestrel

  Participant Flow
  Hide Participant Flow

Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
Eligible participants were recruited via local advertising.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
No enrolled participants were excluded

Reporting Groups
  Description
LNG 1.5 mg Dose, Then Placebo Herb, LNG 1.5 mg Group 1: one-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, followed by placebo herb and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 900 mg Day, LNG 1.5 mg Group 2: One-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, followed by St. John’s Wort 300 mg orally three times per day, and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 900 mg Daily, 2.25 mg LNG Dose Group 3: A one-time oral dose of levonorgestrel 1.5 mg mg at the first pharmacokinetic study, followed by St. John’s Wort 300 mg orally three times per day (900 mg total) and a one-time oral dose of levonorgestrel 2.25 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 1500 ng Day, 1.5 mg LNG Group 4: A one-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, then St. John’s Wort 300 mg orally five times per day (total 1500 mg daily) and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study

Participant Flow for 2 periods

Period 1:   Time 1: First Intervention
    LNG 1.5 mg Dose, Then Placebo Herb, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Day, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Daily, 2.25 mg LNG Dose     LNG 1.5 mg Dose, Then SJW 1500 ng Day, 1.5 mg LNG  
STARTED     9     9     9     9  
COMPLETED     9     9     9     9  
NOT COMPLETED     0     0     0     0  

Period 2:   Time 2: Second Intervention
    LNG 1.5 mg Dose, Then Placebo Herb, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Day, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Daily, 2.25 mg LNG Dose     LNG 1.5 mg Dose, Then SJW 1500 ng Day, 1.5 mg LNG  
STARTED     9     9     9     9  
COMPLETED     9     9     9     9  
NOT COMPLETED     0     0     0     0  



  Baseline Characteristics
  Hide Baseline Characteristics

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
  Description
LNG 1.5 mg Dose, Then Placebo Herb, LNG 1.5 mg Group 1: one-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, followed by placebo herb and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 900 mg Day, LNG 1.5 mg Group 2: One-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, followed by St. John’s Wort 300 mg orally three times per day, and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 900 mg Daily, 2.25 mg LNG Dose Group 3: A one-time oral dose of levonorgestrel 1.5 mg mg at the first pharmacokinetic study, followed by St. John’s Wort 300 mg orally three times per day (900 mg total) and a one-time oral dose of levonorgestrel 2.25 mg at the second pharmacokinetic study
LNG 1.5 mg Dose, Then SJW 1500 ng Day, 1.5 mg LNG Group 4: A one-time oral dose of levonorgestrel 1.5 mg at the first pharmacokinetic study, then St. John’s Wort 300 mg orally five times per day (total 1500 mg daily) and a one-time oral dose of levonorgestrel 1.5 mg at the second pharmacokinetic study
Total Total of all reporting groups

Baseline Measures
    LNG 1.5 mg Dose, Then Placebo Herb, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Day, LNG 1.5 mg     LNG 1.5 mg Dose, Then SJW 900 mg Daily, 2.25 mg LNG Dose     LNG 1.5 mg Dose, Then SJW 1500 ng Day, 1.5 mg LNG     Total  
Number of Participants  
[units: participants]
  9     9     9     9     36  
Age  
[units: participants]
         
<=18 years     0     0     0     0     0  
Between 18 and 65 years     9     9     9     9     36  
>=65 years     0     0     0     0     0  
Age  
[units: years]
Mean ± Standard Deviation
  23.1  ± 3.6     22.4  ± 3.1     23  ± 3.5     22.9  ± 3.4     22.9  ± 3.3  
Gender  
[units: participants]
         
Female     9     9     9     9     36  
Male     0     0     0     0     0  
Region of Enrollment  
[units: participants]
         
United States     9     9     9     9     36  



  Outcome Measures
  Show All Outcome Measures

1.  Primary:   Area Under the Concentration Versus Time Curve for 0 to 24 Hours After Drug Administration, Done Between Days 9 and 12 of the Menstrual Cycle at Time 1 (Before) and Time 2 (During Treatment With St. John's Wort or Placebo)   [ Time Frame: Area Under the Concentration versus Time curve for 0 to 24 hours after drug administration, between Days 9 and 12 of the menstrual cycle, done at Time 1 and at Time 2 ]

2.  Primary:   Number of Participants With Progesterone Levels Above 3.0 ng/ml at Time 1 (Baseline) and Time 2 (After Intervention With St John's Wort or Placebo).   [ Time Frame: Progesterone levels drawn at weekly intervals after dosing with levonorgestrel between Days 9 and 12 of the menstrual cycle, at each time point until menses ]

3.  Primary:   Clearance (L/hr) of Levonorgestrel Over 24 Hours for Each Dosage Group and Each Study Session.   [ Time Frame: Clearance at 24 hours from dosing ]

4.  Secondary:   Mean Levels of Follicle-stimulating Hormone, Estradiol-17b (E2), Luteinizing Hormone, Inhibin, and Glycodelin Drawn at Weekly Intervals Until Next Menses   [ Time Frame: Weekly mean levels of reproductive hormones ]
Results not yet posted.   Anticipated Posting Date:   06/2010   Safety Issue:   No


  Serious Adverse Events


  Other Adverse Events


  Limitations and Caveats
  Hide Limitations and Caveats

Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
Large degree of variability in levonorgestrel levels.


  More Information
  Hide More Information

Certain Agreements:  
Principal Investigators are NOT employed by the organization sponsoring the study.
There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.


Results Point of Contact:  
Name/Title: Patricia Murphy, DrPH
Organization: University of Utah
phone: 801-793-5729
e-mail: patricia.murphy@nurs.utah.edu


Publications:

Responsible Party: Patricia Murphy, DrPH, University of Utah
ClinicalTrials.gov Identifier: NCT00131885     History of Changes
Other Study ID Numbers: 13430, R21AT002297
Study First Received: August 17, 2005
Results First Received: March 21, 2010
Last Updated: August 10, 2011
Health Authority: United States: Federal Government