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NCT03335163 · ClinicalTrials.gov registry record · Phase 1
The Effect of Topiramate on Etonogestrel Concentrations in Contraceptive Implant Users
A Phase 1 study, sponsored by University of Colorado, Denver.
- Completed
- Registry status
- Phase 1
- Development phase
- 48
- Enrollment target
NCT03335163: Completed Phase 1 study, sponsored by University of Colorado, Denver.
NCT03335163 is a Phase 1 study that has completed, run by University of Colorado, Denver. The registered enrollment target is 48 participants, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (20% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03335163, a Phase 1 study, has completed, sponsored by University of Colorado, Denver.
- COMPLETED
- Registry status
- Phase 1
- Development phase
- 48 participants
- Enrollment target
Study Summary
A prospective, non-inferiority study to evaluate the pharmacokinetic effect of topiramate on serum Etonogestrel (ENG) levels in contraceptive implant users.
Primary Outcome
The investigators will collect serum from participants at enrollment and at each of the three study follow-up visits. All samples will be batched for analysis. Analysis will be performed using a liquid-chromatography mass-spectrometry validated assay for measurement of serum etonogestrel concentration.
Interventions
- DRUG Topiramate
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 48 participants |
| Start Date | 2018-03-15 |
| Est. Completion | 2021-04-22 |
| Phase | Phase 1 |
What the finished NCT03335163 record still lists
NCT03335163 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 48 participants, a relatively small participant target, below the 60-participant average among 29,502 other Phase 1 trials with a reported enrollment target (20% lower).
The record links to 0 conditions, and to 1 intervention - of which Topiramate is the first listed.
NCT03335163 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03335163 about?
NCT03335163 is a clinical study titled "The Effect of Topiramate on Etonogestrel Concentrations in Contraceptive Implant Users". A prospective, non-inferiority study to evaluate the pharmacokinetic effect of topiramate on serum Etonogestrel (ENG) levels in contraceptive implant users.
What is the current status of trial NCT03335163?
This trial is currently completed. It is a Phase 1 study. The enrollment target is 48 participants. The study started on 2018-03-15. Estimated completion is 2021-04-22.
What interventions are being tested in trial NCT03335163?
The interventions under investigation include: Topiramate (DRUG).
Who is sponsoring clinical trial NCT03335163?
This trial is sponsored by University of Colorado, Denver, which has 1,283 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03335163's enrollment target sits among peer trials
48 1025th of 2000 higher than 948 of 2,000 other Phase 1 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 1 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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