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Anti-bacterial

Doxycycline for Sexually Transmitted Infections (DOT-Doxy-PEP Trial)

Phase < 1
Recruiting
Led By Matthew Spinelli, MD, MAS
Research Sponsored by University of California, San Francisco
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Transgender men participants should be currently using testosterone gender affirming hormone therapy with blood testosterone levels demonstrating consistent use
Be older than 18 years old
Must not have
Detectable doxycycline in hair at enrollment
Liver cirrhosis or fulminant liver disease
Timeline
Screening 3 weeks
Treatment Varies
Follow Up 4 weeks
Awards & highlights
No Placebo-Only Group

Summary

This trial is looking at the effectiveness of using doxycycline to prevent sexually transmitted infections in different populations. They found that it works well for men who have sex with men and transgender women,

Who is the study for?
This trial is for men who have sex with men and transgender women to test if taking a doxycycline pill after sexual contact can prevent bacterial STIs. Participants should be willing to provide samples for adherence measurement. The study doesn't include cisgender women due to previous findings.
What is being tested?
The study tests the effectiveness of a doxycycline pill as post-exposure prophylaxis (PEP) against STIs in high-risk populations. It also aims to develop methods for measuring medication adherence using hair, blood, and urine samples.
What are the potential side effects?
Potential side effects of doxycycline may include stomach upset, diarrhea, sun sensitivity, tooth discoloration in children, and rarely more serious effects like drug reactions.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
Select...
I am a transgender man using testosterone and my levels show consistent use.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
Select...
Doxycycline is detectable in my hair.
Select...
I have severe liver disease.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~4 weeks
This trial's timeline: 3 weeks for screening, Varies for treatment, and 4 weeks for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Hair Doxycycline Concentration
Plasma Doxycycline Concentration
Urine Doxycycline Concentration

Awards & Highlights

No Placebo-Only Group
All patients enrolled in this study will receive some form of active treatment.

Trial Design

4Treatment groups
Active Control
Group I: Daily DosingActive Control1 Intervention
Participants will be randomized to take once daily doxycycline 200mg for six weeks.
Group II: Three-times Weekly DosingActive Control1 Intervention
Participants will be randomized to take one doxycycline 200mg dose three times a week (Monday, Wednesday, and Friday) for six weeks.
Group III: Weekly DosingActive Control1 Intervention
Participants will be randomized to take one doxycycline 200mg dose once week.
Group IV: Every Other Week DosingActive Control1 Intervention
Participants will be randomized to take one doxycycline 200mg dose every other week.

Find a Location

Who is running the clinical trial?

University of California, San FranciscoLead Sponsor
2,588 Previous Clinical Trials
14,900,959 Total Patients Enrolled
National Institute of Allergy and Infectious Diseases (NIAID)NIH
3,323 Previous Clinical Trials
5,365,126 Total Patients Enrolled
Matthew Spinelli, MD, MASPrincipal InvestigatorUniversity of California, San Francisco
1 Previous Clinical Trials
60 Total Patients Enrolled
~32 spots leftby Sep 2026
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