Doxycycline Prophylaxis for Prevention of Sexually Transmitted Infections
3 other identifiers
interventional
760
1 country
12
Brief Summary
The goal of this open-label, randomized trial is to assess the efficacy of doxycycline prophylaxis in reducing incidences of bacterial sexually transmitted infections (STIs) among adolescent and young adult females while also evaluating acceptability and antimicrobial resistance in order to inform public health policy.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_4
Started Jan 2026
Typical duration for phase_4
12 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
December 12, 2024
CompletedFirst Posted
Study publicly available on registry
December 17, 2024
CompletedStudy Start
First participant enrolled
January 5, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
June 15, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
June 15, 2028
January 2, 2026
December 1, 2025
2.4 years
December 12, 2024
December 30, 2025
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Combined incidence of GC, CT, and/or early syphilis infection
Overall combined incidence of GC, CT, and/or early syphilis infection by laboratory-based diagnosis (defined as positive GC or CT on nucleic acid amplification test \[NAAT\] or first positive rapid plasma reagin \[RPR\] with positive treponemal-specific antibody \[Ab\] or a new 4-fold rise in RPR titers) over the duration of follow-up.
One (1) year
Secondary Outcomes (1)
Individual incidence diagnoses of GC, CT, and early syphilis infection
One (1) year
Other Outcomes (6)
First occurrence of a bacterial STI
One (1) year
Proportion GC isolates that are detected as tetracycline-resistant
One (1) year
Proportion S. aureus isolates that are detected as doxycycline-resistant
One (1) year
- +3 more other outcomes
Study Arms (3)
On-demand doxyPEP
EXPERIMENTALParticipants will take by mouth doxycycline 200 mg as soon as possible and within 72 hours after any condomless oral, vaginal, and/or anal sex in addition to standard of care STI testing/treatment and sexual health counseling.
Weekly doxycycline
EXPERIMENTALParticipants will take by mouth doxycycline 200 mg weekly regardless of sexual activity in addition to standard of care STI testing/treatment and sexual health counseling.
Quarterly STI testing/treatment and sexual health counseling
OTHERParticipants will be followed per standard of care with quarterly STI testing/treatment and sexual health counseling.
Interventions
200 mg of doxycycline taken by mouth as soon as possible and within 72 hours after any condomless oral, vaginal, and/or anal sex along with STI screening and sexual health counseling
Quarterly STI testing/treatment and sexual health counseling
200 mg of doxycycline taken by mouth weekly regardless of sexual activity along with STI screening and sexual health counseling
Eligibility Criteria
You may qualify if:
- Age 13-29 years, inclusive;
- Self-reports GC, CT, and/or early syphilis diagnosis in the 12 months prior to screening;
- Self-reports condomless (oral, vaginal, and/or anal) intercourse at least once in the 30 days prior to screening
- Is at least 45 kilograms (99.2 pounds) in weight
- Fluent in English (able to read, speak, and understand English);
- Willing to undergo all required study procedures; and
- Willing to provide written informed consent to participate in the study.
You may not qualify if:
- Is male;
- Is pregnant, breastfeeding, or planning to become pregnant in the next 12 months;
- Documented history of tetracycline allergy or self-reports an allergy to tetracyclines;
- Current or anticipated use of a medication (e.g., barbiturates, phenytoin, lithium, carbamazepine, systemic retinoids, warfarin) with a contraindicated interaction to doxycycline ;
- Current or planned use of doxycycline for a prolonged period (\> 2 weeks) in the 30 days prior to enrollment, including current prescription for doxycycline for STI prophylaxis;
- Prolonged antibiotic use (\> 2 weeks) within the last 30 days prior to enrollment;
- Co-enrollment in any other concurrent interventional research or studies that may interfere with this study, such as an STI prevention trial, unless approved by Protocol Team in writing;
- Does not have consistent access (or anticipated weekly access for 52 weeks of survey completion) to smartphone that can access the HMP app; or
- Any other medical condition, medical/behavioral intervention, or other conditions that, in the opinion of the clinical site Project Lead (PL)/Investigator of Record (IoR) or designee, could interfere with adherence to study procedures or compromise interpretation of study results.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Westatlead
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)collaborator
- National Institute of Allergy and Infectious Diseases (NIAID)/Division of AIDS (DAIDS)collaborator
- National Institute on Drug Abuse (NIDA)collaborator
- National Institute of Mental Health (NIMH)collaborator
- Florida State Universitycollaborator
- National Institute of Allergy and Infectious Diseases (NIAID)collaborator
- The Office of the Director, National Institutes of Health (NIH)collaborator
Study Sites (12)
UCLA Care
Los Angeles, California, 90095, United States
San Francisco Department of Public Health
San Francisco, California, 94102, United States
Children's National Medical Center
Washington D.C., District of Columbia, 20010, United States
University of Florida
Tampa, Florida, 33612, United States
Ponce de Leon
Atlanta, Georgia, 30303, United States
University Illinois Chicago
Chicago, Illinois, 60612, United States
Tulane University
New Orleans, Louisiana, 70112, United States
Harlem Prevention Center
New York, New York, 10027, United States
Chapel Hill
Chapel Hill, North Carolina, 27599, United States
Penn Prevention
Philadelphia, Pennsylvania, 19104, United States
St. Jude Children's Research Hospital
Memphis, Tennessee, 38015, United States
Baylor College of Medicine
Houston, Texas, 77030, United States
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY CHAIR
Cherie Blaire, MD, PhD
University of California, Los Angeles
- STUDY CHAIR
Jenell Stewart, DO, MPH
Hennepin Healthcare
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 4
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
December 12, 2024
First Posted
December 17, 2024
Study Start
January 5, 2026
Primary Completion (Estimated)
June 15, 2028
Study Completion (Estimated)
June 15, 2028
Last Updated
January 2, 2026
Record last verified: 2025-12
Data Sharing
- IPD Sharing
- Will not share