Fact CheckerSign in

NCT02864550CompletedPhase 4

Oral Doxycycline for the Prevention of Syphilis in Men Who Have Sex with Men (DaDHS)

A Randomized, Placebo-controlled Trial of Oral Doxycycline for the Prevention of Syphilis in HIV-positive Men Who Have Sex with Men (MSM)

Source: ClinicalTrials.gov · Last updated 12 Feb 2025

Brief summary (registry, in English)

Syphilis is a sexually transmitted infection (STI) disproportionately affecting gay, bisexual and other men who have sex with men (gbMSM), with the potential for significant sequelae - particularly in those who are Human Immunodeficiency Virus (HIV)-positive. Rising rates of this STI have prompted a search for novel prevention solutions. A recent pilot study of daily doxycycline prophylaxis demonstrated promise as a novel STI prevention tool. This innovative approach to STI prevention has solid clinical precedent, both from the HIV pre-exposure prophylaxis (PrEP) literature, as well as doxycycline's use as prophylaxis for other infections. The overarching goal of this project is to determine whether the daily use of doxycycline is an efficacious and acceptable intervention for syphilis prevention in high-risk, HIV-positive gbMSM.

Status (registry)
Completed
Phase (registry)
Phase 4
Study type
Interventional
Enrollment
52 (actual)
First submitted
9 Aug 2016
Start date
15 Aug 2019
Primary completion date
5 Apr 2024
Lead sponsor
British Columbia Centre for Disease Control
Diseases
HIV
NCT number
NCT02864550

What you commit to

  • Study type: Interventional · Phase 4
  • Participants enrolled: 52
  • From 15 Aug 2019 to the primary completion date, 5 Apr 2024
  • 1 site in 1 country
  • Visits and tests: ask the trial team, the registry does not list them

Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.

Who cannot take part

Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.

Criteria the registry did not label

  • The inclusion criteria for this study are as follows:
  • Males, ≥ 18 years of age at baseline;
  • Self-reported MSM status;
  • Self-report condomless anal sex with a man within the last 6 months;
  • Laboratory documentation of HIV-1 infection;
  • Prior diagnosis of early/infectious syphilis (i.e. primary, secondary or early latent) within preceding 36 months (defined on the basis of a new positive serum rapid plasma reagin (RPR) test, or ≥2-dilution rise in titre if previous syphilis, or positive darkfield microscopy result or T. pallidum direct fluorescent antibody test or PCR from a primary lesion);
  • Able to provide informed consent.
    • The exclusion criteria for this study are as follows:
  • Known allergy or intolerance to doxycycline or tetracyclines;
  • A known diagnosis of myasthenia gravis;
  • Use of medications which could lower doxycycline levels, including barbiturates, phenytoin and carbamazepine;
  • Individuals using isotretinoin;
  • Any individual capable of getting pregnant.

Age in the registry: 18 years to - · Sex: Male · Does not accept healthy volunteers

Full criteria on ClinicalTrials.gov

Sites (1)

Sites in registry order. Pick your city on the disease page to sort them by distance.

SiteCityCountrySite status
British Columbia Centre for Disease Control
Coordinator of this site? Confirm its status		VancouverCanadaUnknown status

This page is information, not medical advice. Discuss any trial with your doctor.