Phase 4
N=24
Rifampin and the Contraceptive Implant
Contraception · Tuberculosis
Bottom Line
View on ClinicalTrials.gov: NCT04463680 ↗Enrolled (actual)
24
Serious AEs
0.0%
Results posted
May 2023
Primary outcome: Primary: Serum Etonogestrel Concentrations — 164.0; 47.8 pg/mL
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 4
- Interventions
- Rifampin 600 MG (Drug)
- Age
- Adult · 18+ yrs
- Sex
- Female
- Sponsor
- University of Colorado, Denver
- Primary completion
- Feb 2022
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Serum Etonogestrel Concentrations |
164.0; 47.8 | — |
Summary
It is important for women taking rifampin to be aware if they are at greater risk of an unintended pregnancy while on the implant. An unintended pregnancy has many social, emotional, and financial impacts on women and society. Rifampin is also a Class C medication for pregnancy and could have potential negative effects on a developing fetus. Additionally, women considering rifampin for treatment of LTBI face additional risks with an unintended pregnancy, making the reliability of contraception even more important for these women. The results of this study can directly inform counseling on a national and international basis for women who use the contraceptive implant and are considering their treatment options for LTBI.
Eligibility Criteria
Inclusion Criteria
- Healthy women, who have had an ENG implant for 12-36 months at the time of enrollment and will maintain their implant during the study without modifications.
Exclusion Criteria
- o Women who are taking any known cytochrome P-450 3A4 enzyme inducers or inhibitors.
- Women with a known allergy or insensitivity to rifampin.
- Women with a body mass index (BMI) 52 or AST >39, which are beyond the reference range of normal values used by the University of Colorado clinical laboratory. Renal function will be assessed by a serum creatinine and a value >1.2 will be evidence of renal dysfunction as this is greater than the reference range used by the University of Colorado clinical laboratory.
- Women with any abnormal hematology as determined by a complete blood count. For purposes of this study, abnormal hematology will be defined as a WBC, RBC, or PLT value beyond the reference range of normal values used by the University of Colorado clinical laboratory.
- Women with abnormal coagulation factors as determined by coagulation factor tests (PT/INR, PTT). For purposes of this study, abnormal coagulation factors will be defined as any test value beyond the reference range of normal values used by the University of Colorado clinical laboratory.
Data sourced from ClinicalTrials.gov (NCT04463680). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.