Pharmacokinetics of Implanon in Obese Women

Prior studies examining the pharmacokinetics, safety, and efficacy of the new etonogestrel-containing single rod implantable contraceptive device, Implanon, did not include women who exceeded 130% of ideal body weight. Yet, as these women comprise a significant portion of the U.S. population, studies of Implanon in obese women are essential. The proposed study represents an important first step in addressing the lack of data on Implanon in obese women. We aim to examine the pharmacokinetics of Implanon in obese women during the first 6 months of use and to provide data on the acceptability, side effect profile, and ease of insertion, palpation, and removal in these women. We also aim to collect samples for future validation studies of the use of the blood spot (finger-stick blood sample on filter paper) as a method of determining plasma etonogestrel.

Study Overview

• Status: Completed
• Conditions: Obesity; Contraception

• Study Type: Observational
• Enrollment (Actual): 18

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60637
      • University Of Chicago

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from resident and faculty practices at the University of Chicago outpatient facilities and from the University of Chicago clinical trails database of past study participants.

Description

Inclusion Criteria:

• premenopausal with a uterus and at least one ovary
• willing and able to sign the informed consent
• willing to comply with the study protocol and visit schedule
• have a body mass index of less than 25, or greater than or equal to 30
• weight stable

Exclusion Criteria:

• known or suspected pregnancy
• delivery (vaginal or cesarean) within 4 months of device insertion
• abortion (first or second trimester) within 4 months of device insertion
• contraindications to Implanon use
• hemophilia
• undiagnosed abnormal genital bleeding
• hypersensitivity or allergy to any components of Implanon
• personal or family history of thrombosis or thromboembolic disorders
• hepatic tumors or active liver disease
• known or suspected carcinoma of the breast or history of breast cancer
• more that one cardiovascular risk factor such as hypertension or diabetes
• known history of PCOS, diabetes, or glucose abnormality
• present use or use within 2 months of device insertion of a CYP3A4 inducer
• breastfeeding women
• use of an investigational drug within 2 months of device insertion
• use of injectable contraception within 6 months of device insertion
• planning a pregnancy in the next 12 months
• known HIV infection
• smoking over the age of 35

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
1; Obese women: women with a body mass index (BMI) >30
2; Normal weight women: women with a BMI <25

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
To describe the pharmacokinetic profile of Implanon (etonogestrel) among obese women.	6 months

Secondary Outcome Measures

Outcome Measure	Time Frame
To describe ease of insertion and palpation of Implanon among obese women	6 months
To describe bleeding patterns among obese users of Implanon	6 months
To describe the acceptability of Implanon among obese women	6 months
To describe the discontinuation rates, reason for discontinuation, and ease of removal in obese women who discontinue the device before or at the end of the 6 month study period	6 months
To determine whether etonogestrel levels can be obtained from finger-stick blood spots	6 months

Collaborators and Investigators

• Sponsor: University of Chicago
• Collaborators: University of Washington
• Investigators: Principal Investigator: Melissa Gilliam, MD, MPH, University Of Chicago; Study Director: Sara J Mornar, DO, University Of Chicago

Publications and helpful links

Helpful Links

• University of Chicago Section of Family Planning and Contraceptive Research

Study record dates

Study Major Dates

• Study Start: July 1, 2008
• Primary Completion (Actual): August 1, 2009
• Study Completion (Actual): December 1, 2011

Study Registration Dates

• First Submitted: July 25, 2008
• First Submitted That Met QC Criteria: July 28, 2008
• First Posted (Estimate): July 29, 2008

Study Record Updates

• Last Update Posted (Estimate): September 5, 2013
• Last Update Submitted That Met QC Criteria: September 4, 2013
• Last Verified: September 1, 2013

More Information

Terms related to this study

• Keywords: Obesity; Pharmacokinetics; Contraception; Implant; Implanon; Blood spots
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: 15956A