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NCT03980223 · ClinicalTrials.gov registry record · Phase 4
Evaluation of Doxycycline Post-exposure Prophylaxis to Reduce Sexually Transmitted Infections in PrEP Users and HIV-infected Men Who Have Sex With Men
A Phase 4 study, sponsored by University of California, San Francisco.
- Completed
- Registry status
- Phase 4
- Development phase
- 641
- Enrollment target
NCT03980223: Completed Phase 4 study, sponsored by University of California, San Francisco.
NCT03980223 is a Phase 4 study that has completed, run by University of California, San Francisco. The registered enrollment target is 641 participants, above the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (24% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03980223, a Phase 4 study, has completed, sponsored by University of California, San Francisco.
- COMPLETED
- Registry status
- Phase 4
- Development phase
- 641 participants
- Enrollment target
Study Summary
The purpose of this study is to understand if taking an antibiotic called doxycycline by mouth as soon as possible after sexual contact without a condom can reduce the risk of sexually transmitted infections (STIs), including gonorrhea, chlamydia and syphilis. The study will also look at the safety of doxycycline PEP and the impact that PEP may have on the bacteria that cause STIs as well as on bacteria that normally live on the body. While doxycycline is approved by the Food and Drug Administration (FDA), taking doxycycline immediately after sexual contact to prevent infection is investigational and is not approved by the FDA for this use. Participants will take part in the study for 1 year.
Primary Outcome
Number of quarterly visits with an STI event detected.
Interventions
- DRUG Doxycycline Hyclate Delayed-Release 200 mg
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 641 participants |
| Start Date | 2019-11-26 |
| Est. Completion | 2023-06-12 |
| Phase | Phase 4 |
What the finished NCT03980223 record still lists
NCT03980223 is an interventional study that assigns participants to a tested intervention. The registered 641 participants enrollment target is mid-sized for trials with a published cap, above the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (24% higher).
The record links to 0 conditions, and to 1 intervention - of which Doxycycline Hyclate Delayed-Release 200 mg is the first listed.
NCT03980223 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03980223 about?
NCT03980223 is a clinical study titled "Evaluation of Doxycycline Post-exposure Prophylaxis to Reduce Sexually Transmitted Infections in PrEP Users and HIV-infected Men Who Have Sex With Men". The purpose of this study is to understand if taking an antibiotic called doxycycline by mouth as soon as possible after sexual contact without a condom can reduce the risk of sexually transmitted infections (STIs), including gonorrhea, chlamydia and syphilis. The study will also look at the safety ...
What is the current status of trial NCT03980223?
This trial is currently completed. It is a Phase 4 study. The enrollment target is 641 participants. The study started on 2019-11-26. Estimated completion is 2023-06-12.
What interventions are being tested in trial NCT03980223?
The interventions under investigation include: Doxycycline Hyclate Delayed-Release 200 mg (DRUG).
Who is sponsoring clinical trial NCT03980223?
This trial is sponsored by University of California, San Francisco, which has 1,713 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03980223's enrollment target sits among peer trials
641 126th of 2000 higher than 1,874 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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