A Phase 4 interventional study of Doxycycline in STI, sponsored by University of Washington. Completed at 1 site in Kenya. Open to female participants aged 18 Years to 30 Years. Per ClinicalTrials.gov, last updated 2026-04-13.
Sponsored by University of Washington · Phase 4, Interventional, and Prevention
The first study of doxycycline postexposure prophylaxis for cisgender women did not reduce incident STIs likely due to low use of doxycycline. Researchers will conduct a pilot study of once-weekly doxyxycline to prevent bacterial STIs among Kenyan cisgender women using PrEP for HIV prevention.
A study evaluating doxycycline prophylaxis to prevent sexually transmitted infections (STIs) in PrEP-taking African women, who are a priority population for STI prevention, given their high risk and engagement in longitudinal prevention services. The primary study objective is to assess the acceptability of once weekly doxycycline prophylaxis and assess persistence in once weekly doxycycline delivered as directly observed therapy (DOT). STI prophylaxis carries substantial potential benefits but also important potential risks, and we have framed our work as capturing key data to inform this question. Researchers hypothesize that weekly doxycycline will substantially reduce the incidence of curable STIs, particularly C. trachomatis, the most common bacterial STI and the one responsible for greatest morbidity.
Researchers' secondary study objectives are to evaluate the impact on incidence rate of STIs in women given once-weekly doxycycline DOT in comparison with data collected among participants assigned to received standard of care in recently completed dPEP Kenya study as well as to assess tolerability of once weekly doxycycline prophylaxis. Researchers will collect samples for future doxycycline hair drug level testing, antibiotic resistance testing, and microbiome evaluation.
424 studies on the registry are indexed under Sexually Transmitted Diseases; 71 are open to participants now.
This study's enrollment of 60 is below the median of 470 across 346 interventional studies indexed under Sexually Transmitted Diseases.
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Exclusion Criteria:
Open label, single-arm, pilot study of 60 cisgender women taking HIV PrEP in Kisumu, Kenya will be given doxycycline 200 mg orally once weekly with clinical follow-up including quarterly STI testing and treatment for six months.
Drug: Doxycycline
Open label, single-arm, pilot study of 60 cisgender women taking HIV PrEP in Kisumu, Kenya will be given doxycycline 200 mg orally once weekly with clinical follow-up including quarterly STI testing and treatment for six months.
doxyPEP DOT Adherence
Confirmation of weekly doxyPEP DOT dosing each week will be recorded on weekly CRFs and quarterly surveys on acceptability will be completed.
Time frame: 6 months
| Milestone | DoxyDOT Single Arm |
|---|---|
| Started | 60 |
| Completed | 56 |
| Not completed | 4 |
| Withdrew: Withdrawal by subject | 1 |
| Withdrew: Physician decision | 1 |
| Withdrew: Declined study procedures | 1 |
| Withdrew: Lost to follow-up | 1 |
Confirmation of weekly doxyPEP DOT dosing each week will be recorded on weekly CRFs and quarterly surveys on acceptability will be completed.
| Doses | DoxyDOT Single Arm |
|---|---|
| doxyPEP DOT Adherence | 1417 |
Collected over Adverse Events collected from enrollment up to 6 months post-enrollment.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| DoxyDOT Single Arm | 0/60 (0%) | 0/60 (0%) | 5/60 (8.3%) |
| Event | DoxyDOT Single Arm |
|---|---|
| Social harmSocial circumstances | 2/60 |
| MalariaInfections and infestations | 1/60 |
| JaundiceHepatobiliary disorders | 1/60 |
| Physical assaultSocial circumstances | 1/60 |
| Age, Categorical(Participants) | DoxyDOT Single Arm |
|---|---|
| <=18 years | 1 |
| Between 18 and 65 years | 59 |
| >=65 years | 0 |
| Sex: Female, Male(Participants) | DoxyDOT Single Arm |
|---|---|
| Female | 60 |
| Male | 0 |
| Race (NIH/OMB)(Participants) | DoxyDOT Single Arm |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 0 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 60 |
| White | 0 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Region of Enrollment(Participants) | DoxyDOT Single Arm |
|---|---|
| Kenya | 60 |
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