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NCT05840159 · ClinicalTrials.gov registry record · Phase 4
A Study of Doxycycline to Treat Chlamydial Infection
A Phase 4 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- Completed
- Registry status
- Phase 4
- Development phase
- 526
- Enrollment target
NCT05840159: Completed Phase 4 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
NCT05840159 is a Phase 4 study that has completed, run by National Institute of Allergy and Infectious Diseases (NIAID). The registered enrollment target is 526 participants, roughly in line with the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05840159, a Phase 4 study, has completed, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- COMPLETED
- Registry status
- Phase 4
- Development phase
- 526 participants
- Enrollment target
Study Summary
This is a Phase 4 blinded, randomized, active-controlled, non-inferiority trial. Final evaluable population will include a minimum 596 individuals: 298 women with confirmed urogenital chlamydia (CT) and 298 men with confirmed rectal chlamydia (CT). Approximately 664 participants will be enrolled to achieve a minimum 596 participants who contribute primary outcome data. Randomization will be stratified by study site and sex: 332 women and 332 men. Participants will be randomized 1:1 to a 3-day regimen of doxycycline or a 7-day regimen of doxycycline. The study blind will be maintained by providing 7 days of identical pre-filled blister packs, one with 3 days of active treatment and 4 days of placebo, and the other with 7 days of active treatment. Participants will be asked to return 28 days after randomization (at day 29), at which time they will be re-tested for chlamydia (CT) using a laboratory-based chlamydia (CT) nucleic acid amplification test (NAAT).
Primary Outcome
A participant with microbiologic cure is defined as having a negative Chlamydia trachomatis (CT) Nucleic Acid Amplification Test (NAAT) at Day 29 and no positive CT NAATs between study treatment and Day 29
Interventions
- OTHER Placebo
- DRUG Doxycycline
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 526 participants |
| Start Date | 2024-01-19 |
| Est. Completion | 2026-02-12 |
| Phase | Phase 4 |
What the finished NCT05840159 record still lists
NCT05840159 is an interventional study that assigns participants to a tested intervention. The registered 526 participants enrollment target is mid-sized for trials with a published cap, roughly in line with the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target.
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT05840159 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT05840159 about?
NCT05840159 is a clinical study titled "A Study of Doxycycline to Treat Chlamydial Infection". This is a Phase 4 blinded, randomized, active-controlled, non-inferiority trial. Final evaluable population will include a minimum 596 individuals: 298 women with confirmed urogenital chlamydia (CT) and 298 men with confirmed rectal chlamydia (CT). Approximately 664 participants will be enrolled to ...
What is the current status of trial NCT05840159?
This trial is currently completed. It is a Phase 4 study. The enrollment target is 526 participants. The study started on 2024-01-19. Estimated completion is 2026-02-12.
What interventions are being tested in trial NCT05840159?
The interventions under investigation include: Placebo (OTHER), Doxycycline (DRUG).
Who is sponsoring clinical trial NCT05840159?
This trial is sponsored by National Institute of Allergy and Infectious Diseases (NIAID), which has 2,006 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05840159's enrollment target sits among peer trials
526 157th of 2000 higher than 1,844 of 2,000 other Phase 4 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 4 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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