Clinical trial NCT02104609: Effects of Obesity on Pharmacokinetics of the Levonorgestrel Emergency Contraceptive Pill
Official title: Pharmacokinetics of the Levonorgestrel-only Emergency Contraception Regimen in Normal-weight, Obese and Extremely Obese Users: a Pilot Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Obesity
Keywords: Obesity
Emergency contraception
Levonorgestrel emergency contraception
Lead sponsor: University of Southern California
Sponsor class: OTHER
Collaborators: name: Society of Family Planning
First posted: 2014-04-04
Enrollment: 26
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Non-smoking women between ages 18-35 years with regular menstrual cycles (24-35 days) will be enrolled, to include 10 normal weight (BMI = 18.5-24.9 kg/m2) women, 10 obese (BMI = 30-39.9 kg/m2) and 10 extremely obese (BMI ≥ 40 kg/m2) women

Brief summary: The purpose of this study is to determine the effects of obesity on the pharmacokinetics of the levonorgestrel (LNG) only emergency contraceptive (EC) regimen and on markers of ovulation

Primary hypothesis:

1) Obese users of LNG-EC have a pharmacokinetic profile that is consistent with a larger volume of distribution of LNG.

Secondary hypothesis:

1. Alterations in these pharmacokinetic parameters of the LNG-EC regimen in obese women affect the primary mechanism of action, which is inhibition of ovulation.
2. Obesity may affect other factors that alter levels of LNG, such as sex-hormone binding globulin (SHBG) and albumin, which bind LNG and potentially lowers the amount of free LNG.


Eligibility criteria: Inclusion Criteria:

* Women between ages 18-35 years

  * Regular menstrual cycles (24-35 days) for the past 2 months
  * Ovulatory at defined by midluteal progesterone level \>3 ng/mL (Day 18-25)
  * Belongs to one of the following categories: normal weight (BMI = 18.5-24.9 kg/m2), obese (BMI = 30-39.9 kg/m2) or extremely obese (BMI ≥ 40 kg/m2)
  * Participant has no intention of or desire to conceive (e.g., active attempt to become pregnant or in vitro fertilization) for the duration of the study
  * Participant agrees to consistently use an effective method of nonhormonal contraception throughout the duration of study, which could include: condoms (male or female) with or without a spermicidal agent, diaphragm or cervical cap with spermicide, non-hormonal intra-uterine devise (IUD), or sterilization.
  * Able to give informed consent

Exclusion Criteria:

* • Known renal or liver disease

  * Known pituitary disorder
  * Known adrenal disorder
  * Known thyroid disorder
  * Use of medication known to alter the cytochrome P450 system
  * Use of depot-medroxyprogesterone acetate in the previous 6 months or any other hormonal contraceptive in the previous 3 months
  * Currently breastfeeding
  * Pregnant
  * Pregnancy in the prior month
  * Known allergy to medication
  * Other specific contraindications to LNG EC

Primary outcomes:
measure: Maximum concentration (Cmax)
timeFrame: Time 0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 48, 72 hours
Secondary outcomes:
measure: Time to maximum concentration (Tmax)
timeFrame: 0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 48, 72 hours
measure: Minimum concentration (Cmin)
timeFrame: Time 0, 1, 2, 3, 4, 6, 8, 12, 16, 24, 48, 72 hours
measure: Area under the concentration time-curve (AUC)
timeFrame: Time 0, 1, 2, 3, 4, 6, 8, 12, 6, 24, 48, 72 hrs
Other outcomes:
Locations:
city: Los Angeles
country: United States
facility: University of Southern California
state: California
Study officials:
affiliation: University of Southern California
name: M Natavio
role: PRINCIPAL_INVESTIGATOR
References: