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Antibiotic

Doxycycline for Syphilis Prevention

Phase 4

Waitlist Available

Led By Troy Grennan, MD

Research Sponsored by British Columbia Centre for Disease Control

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Males, ≥ 18 years of age at baseline

Self-report condomless anal sex with a man within the last 6 months

Timeline

Screening 3 weeks

Treatment Varies

Follow Up at 6 and 12 months

Awards & highlights

Study Summary

This trial is researching an innovative syphilis prevention tool, doxycycline, for gay, bisexual and other men who have sex with men (gbMSM). PrEP and doxycycline are being used to reduce STI rates in HIV-positive gbMSM.

Who is the study for?

The trial is for HIV-positive gay, bisexual, and other men who have sex with men (gbMSM) over 18 years old. Participants must have had condomless anal sex in the past 6 months and a recent syphilis diagnosis. They can't join if they're allergic to doxycycline or tetracyclines, have myasthenia gravis, use isotretinoin or certain other medications.Check my eligibility

What is being tested?

This study tests whether taking daily doxycycline can prevent syphilis in high-risk gbMSM compared to a placebo. It builds on previous research suggesting that this antibiotic could be an effective preventive measure against sexually transmitted infections.See study design

What are the potential side effects?

Doxycycline may cause side effects like sun sensitivity leading to severe sunburns, upset stomach, diarrhea, and changes in color of teeth enamel. Allergic reactions are possible but participants with known allergies were excluded.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

Select...

I am a man and at least 18 years old.

Select...

I have had unprotected anal sex with a man in the past 6 months.

Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ at 6 and 12 months

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~at 6 and 12 months

This trial's timeline: 3 weeks for screening, Varies for treatment, and at 6 and 12 months for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.

Primary outcome measures

Proportion of individuals with adverse event-related study drug discontinuation in each study arm.

To assess the proportion of individuals reporting grade 3 or 4 adverse events in each study arm.

To assess the proportion of individuals with therapeutic doxycycline drug level (defined at ≥ 1000 ng/mL) at each study time point.

+2 more

Secondary outcome measures

To assess the changes in sexual risk behaviour will be calculated by comparing risk parameters (i.e. number partners, number of anal sexual encounters that were condomless) from pre-PrEP initiation to the study period.

To assess the incidence of early syphilis infection

To assess the incidence of gonorrhea or chlamydia infection

+1 more

Other outcome measures

To assess changes in the bacterial populations found in the rectal microbiome.

Side effects data

From 2021 Phase 4 trial • 26 Patients • NCT04167085

Sinus infection

Metastatic lung cancer dx

Blurred vision

Foot infection

Emesis

Pneumonia

100%

80%

60%

40%

20%

Study treatment Arm

Doxycycline

Placebo

Trial Design

2Treatment groups

Experimental Treatment

Placebo Group

Group I: Doxycycline armExperimental Treatment1 Intervention

Participants in this intervention group will receive doxycycline 100mg orally daily, which is available as a 100mg capsule. This single daily dose was chosen to maximize adherence, given the common use of once-daily Human Immunodeficiency Virus (HIV) pre-exposure prophylaxis (PrEP), as well as its efficacy as once-daily prophylaxis against malaria and its utility as dosing as infrequent as once weekly for another spirochete infection, leptospirosis.

Group II: Placebo armPlacebo Group1 Intervention

Participants in this control group will receive a placebo capsule identical in appearance, taste, and size to the capsule provided to the intervention group.

Treatment

First Studied

Drug Approval Stage

How many patients have taken this drug

Doxycycline

FDA approved

0 / 2Eligibility criteria met

Find a Location

Who is running the clinical trial?

British Columbia Centre for Disease ControlLead Sponsor

10 Previous Clinical Trials

2,531 Total Patients Enrolled

1 Trials studying Syphilis

52 Patients Enrolled for Syphilis

Troy Grennan, MDPrincipal InvestigatorBC Centre for Disease Control

2 Previous Clinical Trials

612 Total Patients Enrolled

1 Trials studying Syphilis

52 Patients Enrolled for Syphilis

Media Library

Doxycycline (Antibiotic) Clinical Trial Eligibility Overview. Trial Name: NCT02864550 — Phase 4

Syphilis Research Study Groups: Doxycycline arm, Placebo arm

Syphilis Clinical Trial 2023: Doxycycline Highlights & Side Effects. Trial Name: NCT02864550 — Phase 4

Doxycycline (Antibiotic) 2023 Treatment Timeline for Medical Study. Trial Name: NCT02864550 — Phase 4

Frequently Asked Questions

These questions and answers are submitted by anonymous patients, and have not been verified by our internal team.

How many participants are included in the present experiment?

"Unfortunately, the recruitment phase for this trial has ended. Initially posted on August 15th 2019 and last updated June 26th 2023, no new candidates are being sought at present. However, there are presently 62 clinical trials actively recruiting patients with syphilis and 31 requiring Doxycycline volunteers."

Answered by AI

What adverse effects may occur from taking Doxycycline?

"There is extensive clinical data in support of Doxycycline's safety, which warranted a score of 3."

Answered by AI

What maladies is Doxycycline widely recommended for?

"Doxycycline is a common medication used to treat severe acne, as well as other maladies such as trachoma and klebsiella infections."

Answered by AI

What are the goals of this clinical experiment?

"The trial's primary outcome, monitored for approximately 15 months, is to determine the number of individuals with a doxycycline level greater than 1000 ng/mL. Secondary objectives include analyzing changes in sexual risk behaviour by assessing variations in condomless encounters and the amount of partners from before Prep initiation until study completion; additionally, evaluating syphilis and other STI incidence throughout the study period will be measured."

Answered by AI

Is this research initiative actively seeking participants?

"This clinical trial has already filled its recruitment quota and is no longer taking on new patients. The study was first posted in August 2019, although the last revision to the page occured in June of 2023. There are currently 62 studies recruiting for syphilis-related trials and 31 operations looking for volunteers to take part while being administered doxycycline."

Answered by AI

Recent research and studies

New England Journal of MedicineJournal

Declining Morbidity and Mortality Among Patients with Advanced Human Immunodeficiency Virus Infection

Palella, Frank J., Jr., Kathleen M. Delaney, Anne C. Moorman, Mark O. Loveless, Jack Fuhrer, Glen A. Satten, Diane J. Aschman, and Scott D. Holmberg. 1998. “Declining Morbidity and Mortality Among Patients with Advanced Human Immunodeficiency Virus Infection”. New England Journal of Medicine. Massachusetts Medical Society. doi:10.1056/nejm199803263381301.

New England Journal of MedicineJournal

Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men

Grant, Robert M., Javier R. Lama, Peter L. Anderson, Vanessa McMahan, Albert Y. Liu, Lorena Vargas, Pedro Goicochea, et al.. 2010. “Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men”. New England Journal of Medicine. Massachusetts Medical Society. doi:10.1056/nejmoa1011205.

Sexually Transmitted DiseasesJournal

Doxycycline Prophylaxis to Reduce Incident Syphilis Among Hiv-infected Men Who Have Sex with Men Who Continue to Engage in High-risk Sex

Bolan, Robert K., Matthew R. Beymer, Robert E. Weiss, Risa P. Flynn, Arleen A. Leibowitz, and Jeffrey D. Klausner. 2015. “Doxycycline Prophylaxis to Reduce Incident Syphilis Among Hiv-infected Men Who Have Sex with Men Who Continue to Engage in High-risk Sex”. Sexually Transmitted Diseases. Ovid Technologies (Wolters Kluwer Health). doi:10.1097/olq.0000000000000216.

clinicaltrials.govStudy