Den här översättningen är inte klar ännu. Den här sidan är just nu på engelska.

Gå till den engelska sidan

Cure My Disease

Don't miss your cure!

 Log in / Sign up

Rio study tests antibiotic after sex to stop STIs

NCT ID NCT07500415

Prevention Sponsor: Oswaldo Cruz Foundation Source: ClinicalTrials.gov ↗

What the study statuses mean

This study's is highlighted.

Recruitment status, easiest to join first

Recruiting now This study
This trial is taking on new participants right now.
Not yet recruiting
Registered, but not yet taking participants.
By invitation only
Not open to general applications. Only people the study team invites can take part.
Paused
Paused for now. It may or may not start again.
Ongoing
Running, but no longer taking on new participants.
Completed
The trial has finished. Results may not be published yet.
Stopped early
Stopped early, before it reached the end. That can be for many reasons, including safety.
Cancelled
Cancelled before anyone took part.

Expanded access (not trials)

Expanded access
Not a trial. This treatment can be requested outside a study, case by case, for people who qualify.
Expanded access (paused)
Not a trial. The treatment can normally be requested outside a study, but is unavailable right now.
Expanded access (ended)
Not a trial. The treatment could once be requested outside a study, but no longer can.
Approved
The treatment has been approved, so it is available normally rather than through this programme.

When the status isn't known

Details not published
The full record has not been published yet, so there is little to show here.
Status unknown
This status has not been confirmed recently, so it may be out of date.

First seen Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study tests whether taking the antibiotic doxycycline shortly after sex can prevent bacterial STIs like syphilis, gonorrhea, and chlamydia. It involves 200 men, transgender women, and travestis in Rio de Janeiro who are at higher risk. Participants choose whether to use doxy-PEP and are followed for 48 weeks to see if it reduces infections and is safe.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Study facts

What this study's own registry entry says, in plain language.

Phase

Not a phased trial

Phase numbers describe drug development. The registry uses this when they do not apply, as it does for trials of devices, procedures or behaviour changes, and for observational studies.

Participants

About 200 people

The number the study aims to enrol. It can still change while the study runs.

Started

Oct 2025

Expected to finish

May 2028

An estimate. End dates often move.

Lead sponsor

Other sponsor

The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.

Who can take part

This study's own entry requirements. Only the study team can say for certain whether you qualify.

Ages

18 years and older

Sex

Anyone

Healthy volunteers

Accepted

You do not need to have the condition being studied to take part.

Show the full entry requirements

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Individuals assigned male at birth (cisgender or transgender men), transgender women, or travestis who have sex with men * Age ≥18 years * Living with HIV or currently using HIV pre-exposure prophylaxis (PrEP) for at least 6 months * History of at least one bacterial sexually transmitted infection (chlamydia, gonorrhea, or syphilis) in the past 12 months (laboratory-confirmed or self-reported) * Willing and able to provide informed consent Exclusion Criteria: * Known allergy or hypersensitivity to doxycycline or other tetracycline-class antibiotics * Current use of medications that may significantly interact with doxycycline or are contraindicated, including systemic retinoids, barbiturates, carbamazepine, or phenytoin

Get updates

Get notified about this study

Sign up to get updates when this study changes or when new studies for Chlamydia infections are added.

Vår säkerhetsrekommendation!

Genom att skicka in godkänner du våra Användarvillkor

Conditions

The condition(s) this trial relates to.

HIV infectious disease sexually transmitted disease bacterial sexually transmitted disease prevention target chlamydia infectious disease prevention target gonorrhea prevention target syphilis prevention target

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Chlamydia infections Gonorrhea HIV infections Sexually transmitted diseases Syphilis

How to take part

Only the study team decides who joins. These are the ways to reach them.

  1. The places running it

    1 site. The list below names each one and where it is.

  2. The official record

    ClinicalTrials.gov lists the study team's own contact details, including names and phone numbers. We don't republish those.

    Open the record ↗

  3. A doctor treating you

    A doctor who knows your case can contact a study site on your behalf, and can tell you whether this study is worth pursuing at all.

Contacts and locations

Locations

  • Instituto Nacional de Infectologia Evandro Chagas

    RECRUITING

    Rio de Janeiro, Rio de Janeiro, 21040-360, Brazil

More trials for these conditions

Other studies related to the condition(s) this trial covers.