Clinical trial NCT06738407: Doxycycline Prophylaxis for Prevention of Sexually Transmitted Infections
Official title: Doxycycline Prophylaxis for Prevention of Sexually Transmitted Infections Among Adolescent and Young Adult Females in the United States
Study type: INTERVENTIONAL
Overall status: SUSPENDED
Phase: PHASE4
Conditions: Gonorrhea
Chlamydia
Syphilis
Sexually Transmitted Infections (STIs)
Keywords: Sexually Transmitted Infections
STIs
Doxycycline Prophylaxis
Doxycycline
Lead sponsor: Westat
Sponsor class: OTHER
Collaborators: name: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
name: National Institute of Allergy and Infectious Diseases (NIAID)/Division of AIDS (DAIDS)
name: National Institute on Drug Abuse (NIDA)
name: National Institute of Mental Health (NIMH)
name: National Institutes of Health (NIH)
name: Florida State University
First posted: 2024-12-17
Enrollment: 760
Sex: FEMALE
Minimum age (years): 13
Maximum age (years): 29
Standard ages: CHILD
ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Participants will be randomized 1:1:1 to (1) on-demand doxyPEP (doxycycline 200 mg as soon as possible and within 72 hours after any condomless oral, vaginal, and/or anal sex), (2) weekly doxycycline (doxycycline 200 mg weekly regardless of sexual activity), or (3) SOC (quarterly STI testing/treatment and sexual health counseling). Participants will complete quarterly study visits over the course of 1 year during which they will receive STI testing (GC, CT, and syphilis), complete surveys, undergo safety monitoring, provide specimens for objective markers of doxycycline adherence and other laboratory assessments, and provide specimens (vaginal and rectal swabs \[participant self-collected or staff-collected if the participant prefers\]) for future testing, such as microbiome analysis.
Primary purpose: PREVENTION

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.

Detailed description: Participants will be randomized to receive on-demand doxycycline post-exposure prophylaxis (doxyPEP), weekly doxycycline, or standard of care (SOC) and will be followed quarterly to assess the impact of doxycycline use on the quarterly incidence of STIs (gonorrhea \[GC\], chlamydia \[CT\], and early syphilis), and within the doxycycline arms adherence and acceptability of weekly versus on-demand dosing.

Approximately 760 females will be randomized 1:1:1 to (1) on-demand doxyPEP (doxycycline 200 mg as soon as possible and within 72 hours after any condomless oral, vaginal, and/or anal sex), (2) weekly doxycycline (doxycycline 200 mg weekly regardless of sexual activity), or (3) SOC (quarterly STI testing/treatment and sexual health counseling). Participants will complete quarterly study visits over the course of 1 year during which they will receive STI testing (GC, CT, and syphilis), complete surveys, undergo safety monitoring, provide specimens for objective markers of doxycycline adherence and other laboratory assessments, and provide specimens (vaginal and rectal swabs \[participant self-collected or staff-collected if the participant prefers\]) for future testing, such as microbiome analysis. Resistance testing will be conducted on Staphylococcus (S.) aureus and Neisseria (N.) gonorrhoeae isolates to evaluate for doxycycline and tetracycline resistance, respectively. Participants will also complete weekly assessments of sexual activity and doxycycline adherence via the HealthMpowerment (HMP) application (app).

Eligibility criteria: Inclusion Criteria:

* 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.

Exclusion Criteria:

* Is male;
* Is pregnant, breastfeeding, or planning to become pregnant in the next 12 months;
* Reports 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.

Primary outcomes:
measure: Combined incidence of GC, CT, and/or early syphilis infection
timeFrame: One (1) year
Secondary outcomes:
measure: Individual incidence diagnoses of GC, CT, and early syphilis infection
timeFrame: One (1) year
Other outcomes:
measure: First occurrence of a bacterial STI
timeFrame: One (1) year
measure: Proportion GC isolates that are detected as tetracycline-resistant
timeFrame: One (1) year
measure: Proportion S. aureus isolates that are detected as doxycycline-resistant
timeFrame: One (1) year
measure: Adherence to doxycycline
timeFrame: One (1) year
measure: Acceptability and optimism
timeFrame: One (1) year
Locations:
city: Los Angeles
country: United States
facility: UCLA Care
state: California
city: Washington
country: United States
facility: Children's National Medical Center
state: District of Columbia
city: Atlanta
country: United States
facility: Ponce de Leon
state: Georgia
city: Chicago
country: United States
facility: University Illinois Chicago
state: Illinois
city: New Orleans
country: United States
facility: Tulane University
state: Louisiana
city: New York
country: United States
facility: Callen-Lorde Community Health Center
state: New York
city: New York
country: United States
facility: Harlem Prevention Center
state: New York
city: Chapel Hill
country: United States
facility: Chapel Hill
state: North Carolina
city: Philadelphia
country: United States
facility: Penn Prevention
state: Pennsylvania
city: Memphis
country: United States
facility: St. Jude Children's Research Hospital
state: Tennessee
city: Houston
country: United States
facility: Baylor College of Medicine
state: Texas
Study officials:
affiliation: University of California, Los Angeles
name: Cherie Blaire, MD, PhD
role: STUDY_CHAIR
affiliation: Hennepin Healthcare
name: Jenell Stewart, DO, MPH
role: STUDY_CHAIR
References: